Direct detection of Salmonella from poultry samples by DNA isothermal amplification.

1. Salmonellosis is one of the most important diseases in public health and it is usually associated with poultry product consumption. This study aimed to validate rapid methods to detect Salmonella spp. from poultry samples. 2. A DNA isothermal amplification method, previously developed for other matrices, was applied for the specific detection of Salmonella spp. from various samples, including poultry tissues, drag and boot swabs, faeces and feed. A new procedure was validated with Salmonella spp. serotypes and isolates from other enteric bacterial species, as well as naturally contaminated poultry samples. 3. The study demonstrated the successful development and implementation of a procedure, including a DNA isothermal amplification method, for the detection of Salmonella spp. directly from tissues, drag and boot swabs, faeces and feed. The whole procedure can be performed in less than 24 hours and it has been successfully used in a veterinary diagnostic laboratory.

Speed-dependent modulation of wing muscle recruitment intensity and kinematics in two bat species.

Animals respond to changes in power requirements during locomotion by modulating the intensity of recruitment of their propulsive musculature, but many questions concerning how muscle recruitment varies with speed across modes of locomotion remain unanswered. We measured normalized average burst EMG (aEMG) for pectoralis major and biceps brachii at different flight speeds in two relatively distantly related bat species: the aerial insectivore Eptesicus fuscus, and the primarily fruit-eating Carollia perspicillata These ecologically distinct species employ different flight behaviors but possess similar wing aspect ratio, wing loading and body mass. Because propulsive requirements usually correlate with body size, and aEMG likely reflects force, we hypothesized that these species would deploy similar speed-dependent aEMG modulation. Instead, we found that aEMG was speed independent in E. fuscus and modulated in a U-shaped or linearly increasing relationship with speed in C. perspicillata This interspecific difference may be related to differences in muscle fiber type composition and/or overall patterns of recruitment of the large ensemble of muscles that participate in actuating the highly articulated bat wing. We also found interspecific differences in the speed dependence of 3D wing kinematics: E. fuscus modulates wing flexion during upstroke significantly more than C. perspicillata Overall, we observed two different strategies to increase flight speed: C. perspicillata tends to modulate aEMG, and E. fuscus tends to modulate wing kinematics. These strategies may reflect different requirements for avoiding negative lift and overcoming drag during slow and fast flight, respectively, a subject we suggest merits further study.

Spring or string: does tendon elastic action influence wing muscle mechanics in bat flight?

Tendon springs influence locomotor movements in many terrestrial animals, but their roles in locomotion through fluids as well as in small-bodied mammals are less clear. We measured muscle, tendon and joint mechanics in an elbow extensor of a small fruit bat during ascending flight. At the end of downstroke, the tendon was stretched by elbow flexion as the wing was folded. At the end of upstroke, elastic energy was recovered via tendon recoil and extended the elbow, contributing to unfurling the wing for downstroke. Compared with a hypothetical 'string-like' system lacking series elastic compliance, the tendon spring conferred a 22.5% decrease in muscle fascicle strain magnitude. Our findings demonstrate tendon elastic action in a small flying mammal and expand our understanding of the occurrence and action of series elastic actuator mechanisms in fluid-based locomotion.

Frequency stabilization of an optically pumped far-infrared laser to the harmonic of a microwave synthesizer.

Measurements of the frequency stability of a far-infrared molecular laser have been made by mixing the harmonic of an ultrastable microwave source with a portion of the laser output signal in a terahertz (THz) Schottky diode balanced mixer. A 3 GHz difference-frequency signal was used in a frequency discriminator circuit to lock the laser to the microwave source. Comparisons of the short- and long-term laser frequency stability under free-running and locked conditions show a significant improvement with locking. Short-term frequency jitter was reduced by an order of magnitude, from approximately 40 to 4 kHz, and long-term drift was reduced by more than three orders of magnitude, from approximately 250 kHz to 80 Hz. The results, enabled by the efficient Schottky diode balanced mixer downconverter, demonstrate that ultrastable microwave-based frequency stabilization of THz optically pumped lasers (OPLs) will now be possible at frequencies extending well above 4.0 THz.

Porcine sialoadhesin: a newly identified xenogeneic innate immune receptor.

Extracorporeal porcine liver perfusion is being developed as a bridge to liver allotransplantation for patients with fulminant hepatic failure. This strategy is limited by porcine Kupffer cell destruction of human erythrocytes, mediated by lectin binding of a sialic acid motif in the absence of antibody and complement. Sialoadhesin, a macrophage restricted lectin that binds sialic acid, was originally described as a sheep erythrocyte binding receptor. Given similarities between sialoadhesin and the unidentified macrophage lectin in our model, we hypothesized porcine sialoadhesin contributed to recognition of human erythrocytes. Two additional types of macrophages were identified to bind human erythrocytes-spleen and alveolar. Expression of sialoadhesin was confirmed by immunofluorescence in porcine tissues and by flow cytometry on primary macrophages. A stable transgenic cell line expressing porcine sialoadhesin (pSn CHO) bound human erythrocytes, while a sialoadhesin mutant cell line did not. Porcine macrophage and pSn CHO recognition of human erythrocytes was inhibited approximately 90% by an antiporcine sialoadhesin monoclonal antibody and by human erythrocyte glycoproteins. Furthermore, this binding was substantially reduced by sialidase treatment of erythrocytes. These data support the hypothesis that porcine sialoadhesin is a xenogeneic receptor that mediates porcine macrophage binding of human erythrocytes in a sialic acid-dependent manner.

Would evidence-based regulation improve the practice and management of patient care?

The use of evidence to achieve sound medical diagnoses and optimal treatment plans is considered a standard of practice for healthcare providers. Indeed, failure to do so is prima facie evidence of malpractice. Health and medical care managers have begun espousing a similar philosophy: to make decisions that are data-driven rather than based on logic, intuition, personal preference, or last experience. Unfortunately, regulatory policies and practices in patient care are not always founded upon strong evidence. As a result, unintended consequences often surface after the passage of legislation or the adoption of policies by nongovernmental entities. These dysfunctions might be avoided if policymakers embraced evidence-based protocols commonly found throughout medicine and its management. This paper reviews the dilemmas that unfold when policy is formed without giving sufficient attention, in advance, to "hard" evidence.

Strategic planning to reduce medical errors: Part II--therapy.

In Part I of this series, medical errors were analyzed from a systems dynamics viewpoint. It was noted that despite extensive dialogue and a continuing stream of proposed medical practice revisions, medical errors and adverse impacts persist. Connectivity of vital elements is often underestimated or not fully understood. In Part II, our analysis suggests that the most fruitful strategies for dissolving medical errors include facilitating physician learning, educating patients about appropriate expectations surrounding treatment regimens, and creating "systematic" patient protections rather than depending on (nonexistent) perfect providers.

Strategic planning to reduce medical errors: Part I--diagnosis.

Despite extensive dialogue and a continuing stream of proposed medical practice revisions, medical errors and adverse impacts persist. Connectivity of vital elements is often underestimated or not fully understood. This paper analyzes medical errors from a systems dynamics viewpoint (Part I). Our analysis suggests in Part II that the most fruitful strategies for dissolving medical errors include facilitating physician learning, educating patients about appropriate expectations surrounding treatment regimens, and creating "systematic" patient protections rather than depending on (nonexistent) perfect providers.

Intimate partner violence and partner notification of sexually transmitted infections among adolescent and young adult family planning clinic patients.

Patient-initiated partner notification of sexually transmitted infection (STI), i.e. patients informing their sexual partners of a diagnosis, is a cornerstone of STI prevention. Growing evidence suggests that women exposed to intimate partner violence (IPV) may fear such notification, or face negative consequences in response to STI disclosure. The current study assessed associations of IPV with fear of partner notification, and experiences of partner notification, among adolescent and young adult female family planning clinic patients. Women aged 16-29 years attending five family planning clinics in Northern California, USA (n = 1282) participated in a cross-sectional survey. A history of physical or sexual IPV was associated with fear of partner notification. Moreover, participants exposed to IPV were more likely to have partners say that it was not from them or otherwise accuse them of cheating in response to partner notification. Such partners were less likely to seek indicated STI treatment or testing. Current findings suggest that partner notification for STI may be compromised by IPV. Clinical practices and policies to support effective partner notification should include IPV assessment, and provide mechanisms to address related fears concerning partner notification.

The shocking cost of turnover in health care.

Review of turnover costs at a major medical center helps health care managers gain insights about the magnitude and determinants of this managerial challenge and assess the implications for organizational effectiveness. Here, turnover includes hiring, training, and productivity loss costs. Minimum cost of turnover represented a loss of >5 percent of the total annual operating budget. Editor's Note: This article is being reprinted with permission from Health Care Management Review 29(1), 2-7.

Overlapping spectra of SMAD4 mutations in juvenile polyposis (JP) and JP-HHT syndrome.

Juvenile polyposis (JP) and hereditary hemorrhagic telangiectasia (HHT) are clinically distinct diseases caused by mutations in SMAD4 and BMPR1A (for JP) and endoglin and ALK1 (for HHT). Recently, a combined syndrome of JP-HHT was described that is also caused by mutations in SMAD4. Although both JP and JP-HHT are caused by SMAD4 mutations, a possible genotype:phenotype correlation was noted as all of the SMAD4 mutations in the JP-HHT patients were clustered in the COOH-terminal MH2 domain of the protein. If valid, this correlation would provide a molecular explanation for the phenotypic differences, as well as a pre-symptomatic diagnostic test to distinguish patients at risk for the overlapping but different clinical features of the disorders. In this study, we collected 19 new JP-HHT patients from which we identified 15 additional SMAD4 mutations. We also reviewed the literature for other reports of JP patients with HHT symptoms with confirmed SMAD4 mutations. Our combined results show that although the SMAD4 mutations in JP-HHT patients do show a tendency to cluster in the MH2 domain, mutations in other parts of the gene also cause the combined syndrome. Thus, any mutation in SMAD4 can cause JP-HHT. Any JP patient with a SMAD4 mutation is, therefore, at risk for the visceral manifestations of HHT and any HHT patient with SMAD4 mutation is at risk for early onset gastrointestinal cancer. In conclusion, a patient who tests positive for any SMAD4 mutation must be considered at risk for the combined syndrome of JP-HHT and monitored accordingly.

Retention of chairs in obstetrics and gynecology: a comparison with other clinical departments.

OBJECTIVE: To compare the retention of chairs in academic obstetrics and gynecology with other core clinical departments. METHODS: Ongoing data were collected from each medical school for the Association of American Medical Colleges Faculty Roster between 1979 and 2007. Primary outcome measures included 5-year and 10-year retention rates and survival curves of first-time chairs. Comparisons were made between first-time chairs in obstetrics and gynecology and other core clinical departments: internal medicine, family medicine, pediatrics, psychiatry, and surgery. RESULTS: Five-year retention rates of obstetrics and gynecology chairs declined from 80% for those who began in 1979-1982 to 53% for those who began in 1998-2002. Ten-year retention in obstetrics and gynecology declined from 54% for those beginning in 1979-1982 to 26% for those beginning in 1993-1997. Other clinical departments experienced more stable 5-year and 10-year retention rates. Although substantially longer than other clinical departments in the 1979-1982 cohort, the median tenure of obstetrics and gynecology chairs who began in 1993-1997 was comparable with or less than that of other clinical departments. Discrete-time survival analysis revealed this decline in obstetrics and gynecology chair retention to be significant (P<.001) and more consistent than in other departments. CONCLUSION: Compared with other core clinical departments, retention of first-time chairs in obstetrics and gynecology declined more consistently from the highest to among the lowest. Chairs were inclined to not remain in office for a prolonged period. LEVEL OF EVIDENCE: II.

Postshunt hemochromatosis leading to cardiogenic shock in a patient presenting for orthotopic liver transplant: a case report.

INTRODUCTION: In this case report, we have presented a patient whose liver transplant course was greatly affected by a previously undiagnosed disease process that ultimately led to an unexpected perioperative death. CASE REPORT: A 52-year-old woman with idiopathic hepatoportal sclerosis presented for liver transplantation 2 years postmesocaval shunt placement. Lab and pathology studies at the time of liver biopsy and shunt placement were negative for iron deposition. Preoperative workup was negative for cardiac disease. At the outset of her liver transplant, the patient developed refractory hypotension secondary to cardiogenic shock. Intraoperative transesophageal echocardiography and postoperative transthoracic echocardiography demonstrated dilated cardiomyopathy with severely depressed systolic function. Upon succumbing to ventricular fibrillation cardiac arrest, an autopsy revealed hemochromatosis of the heart, pancreas, kidneys, adrenals, and explanted liver. CONCLUSION: Dilated cardiomyopathy, congestive heart failure, and other unexpected disease processes resulting from hemochromatosis can greatly influence the care of postshunt liver failure patients.

Learning - the only way to improve health-care outcomes.

Attempts to improve health care have generally failed. Systems analysis urges addressing processes, such as learning, rather than isolated parts of a system. We apply learning curve theory to health care and then explicate the process of learning. Specific recommendations involve how we learn (and unlearn), who should learn, and what should be learned.

Change your metrics: if you get what you measure, then measure what you want--retention.

What we want is retention, not turnover, of our workforce. We should measure what we want-net retention-which is a fundamentally different metric from turnover (not its inverse). Net retention is a highly useful managerial tool, especially for fiscal and strategic planning. Retention enables learning and therefore can facilitate improved medical and organizational outcomes. To retain our workforce and achieve superior results, we must clarify priorities; change our metrics, particularly to long-term outcomes; use evidence-based medicine and evidence-based management; apply the "internal customer" concept; and utilize systems thinking.

Healthcare CEOs and physicians: reaching common ground.

A survey of 670 hospital and health system CEOs was conducted to understand why they chose a career path to CEO, what characteristics typify their career paths, and what major concerns they have about the future. Respondents expressed very strong altruistic reasons for becoming CEO, a finding that is consistent with the rationale many physicians express for entering medical practice. Early CEO career paths were diverse but typically led respondents to a senior managerial position before becoming CEO. Nine percent started as direct providers of healthcare. The respondents' most frequently expressed concerns for the future centered on reimbursement/financing issues and staffing shortages. Physicians may be surprised to learn that healthcare CEOs share their core values, experience similar frustrations, and have identical fears about the future of healthcare. Rather than emphasizing the differences between CEOs and doctors as a stumbling block to alliance, we urge the establishment of a common ground based on similar core values and purposes that will lead to improved communication and the powerful combination of talents derived from collegial collaboration.

Improving medical practice outcomes by retaining clinicians.

Turnover of medical care providers has become so commonplace that callous disregard or weary resignation are prevailing sentiments among remaining staff members when a colleague leaves. This article analyzes reasons for turnover of caregivers and the consequences. Turnover is particularly detrimental in medical practice because it undermines learning, as well as acquisition of judgment and adaptability. Medical practice managers may be unaware of the magnitude of the hidden costs-financial, strategic, and quality-associated with turnover. Strategies are proposed to assist medical care organizations in retaining clinicians and thereby improving healthcare effectiveness and efficiency.

Creating a favorable practice environment for nurses.

Chronic nurse turnover and attendant personnel shortages threaten patient care. Inadequate pay and benefits are primary factors leading to nurses' job dissatisfaction and, subsequently, to turnover. However, recent meta-analyses suggest that a favorable practice setting can improve nurses' satisfaction and minimize turnover. The practice environment's potential to positively influence nurses' job satisfaction is analyzed in a large academic medical center. Nurse supervisors, job characteristics, management style, and service quality emphasis--not just money and benefits--surface as key factors associated with a positive practice milieu. Implications for raising nurses' job satisfaction, reducing turnover, and improving care delivery are discussed.

Environmental tobacco smoke leakage from smoking rooms.

Twenty-seven laboratory experiments were conducted in a simulated smoking room to quantify rates of environmental tobacco smoke (ETS) leakage to a nonsmoking area as a function of the physical and operational characteristics of the smoking room. Data are presented for the various types of leakage flows, the effect of these leaks on smoking room performance and nonsmoker exposure, and the relative importance of each leakage mechanism. The results indicate that the first priority for an effective smoking room is to maintain it depressurized with respect to adjoining nonsmoking areas. The amount of ETS pumped out by the smoking room door when it is opened and closed can be reduced significantly by substituting a sliding door for the standard swing-type door. An "open doorway" configuration used twice the ventilation flow of those with smoking room doors, but yielded less reduction in nonsmoker exposure. Measured results correlated well with results modeled with mass-balance equations (R(2) = 0.82-0.99). Most of these results are based on sulfur hexafluoride (SF(6)) tracer gas leakage. Because five measured ETS tracers showed good correlation with SF(6), these conclusions should apply to ETS leakage as well. Field tests of a designated smoking room in an office building qualitatively agreed with model predictions.