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Rabies is a lethal zoonotic encephalomyelitis that causes an estimated 59,000 human deaths yearly worldwide. Although developing countries of Asia and Africa bear the heaviest burden, surveillance and disease detection in these countries is often hampered by the absence of local laboratories able to diagnose rabies and/or the difficulties of sample shipment from low-access areas to national reference laboratories. Filter papers offer a convenient cost-effective alternative for the sampling, shipment, and storage of biological materials for the diagnosis of many pathogens including rabies virus, yet the properties of diagnostic tests using this support have not been evaluated thoroughly. Sensitivity and specificity of molecular diagnosis of rabies infection using a reverse transcription followed by a hemi-nested polymerase chain reaction (RT-hn-PCR) either directly on brain tissue or using brain tissue dried on filter paper were assessed on 113 suspected field animal samples in comparison to the direct fluorescent antibody test (FAT) recommended by the World Health Organization as one of the reference tests for rabies diagnosis. Impact of the duration of the storage was also evaluated. The sensitivity and the specificity of RT-hn-PCR i) on brain tissue were 96.6% (95% CI: [88.1-99.6]) and 92.7% (95% CI: [82.4-98.0]) respectively and ii) on brain tissue dried on filter paper 100% (95% CI: [93.8-100.0]) and 90.9% (95% CI: [80.0-97.0]) respectively. No loss of sensitivity of RT-hn-PCR on samples of brain tissue dried on filter paper left 7 days at ambient temperature was detected indicating that this method would enable analyzing impregnated filter papers sent to the national reference laboratory at ambient temperature within a 1-week shipment time. It could therefore be an effective alternative to facilitate storage and shipment of samples from low-access areas to enhance and expand rabies surveillance.

Specimens were obtained from the 3 Malagasy fruit bats, Pteropus rufus, Eidolon dupreanum, and Rousettus madagascariensis. Antibodies against Nipah, Hendra, and Tioman viruses were detected by immunoassay in 23 and by serum neutralization tests in 3 of 427 serum samples, which suggests that related viruses have circulated in Madagascar.

Retained hemothorax (RH) is a commonly encountered and potentially severe complication of intrapleural bleeding that can organize with lung restriction. Early surgical intervention and intrapleural fibrinolytic therapy have been advocated. However, the lack of a reliable, cost-effective model amenable to interventional testing has hampered our understanding of the role of pharmacological interventions in RH management. Here, we report the development of a new RH model in rabbits. RH was induced by sequential administration of up to three doses of recalcified citrated homologous rabbit donor blood plus thrombin via a chest tube. RH at 4, 7, and 10 days post-induction (RH4, RH7, and RH10, respectively) was characterized by clot retention, intrapleural organization, and increased pleural rind, similar to that of clinical RH. Clinical imaging techniques such as ultrasonography and computed tomography (CT) revealed the dynamic formation and resorption of intrapleural clots over time and the resulting lung restriction. RH7 and RH10 were evaluated in young (3 mo) animals of both sexes. The RH7 recapitulated the most clinically relevant RH attributes; therefore, we used this model further to evaluate the effect of age on RH development. Sanguineous pleural fluids (PFs) in the model were generally small and variably detected among different models. The rabbit model PFs exhibited a proinflammatory response reminiscent of human hemothorax PFs. Overall, RH7 results in the consistent formation of durable intrapleural clots, pleural adhesions, pleural thickening, and lung restriction. Protracted chest tube placement over 7 d was achieved, enabling direct intrapleural access for sampling and treatment. The model, particularly RH7, is amenable to testing new intrapleural pharmacologic interventions, including iterations of currently used empirically dosed agents or new candidates designed to safely and more effectively clear RH.

The incidence of empyema is increasing and associated with a mortality rate of 20% in patients older than 65 years. Since 30% of patients with advanced empyema have contraindications to surgical treatment, novel, low-dose, pharmacological treatments are needed. A Streptococcus pneumoniae -induced rabbit model of chronic empyema recapitulates the progression, loculation, fibrotic repair, and pleural thickening of human disease. Treatment with single chain (sc) urokinase (scuPA) or tissue type (sctPA) plasminogen activators in doses 1.0-4.0 mg/kg were only partially effective in this model. Docking Site Peptide (DSP; 8.0 mg/kg), which decreased the dose of sctPA for successful fibrinolytic therapy in acute empyema model did not improve efficacy in combination with 2.0 mg/kg scuPA or sctPA. However, a two-fold increase in either sctPA or DSP (4.0 and 8.0 mg/kg or 2.0 and 16.0 mg/kg sctPA and DSP, respectively) resulted in 100% effective outcome. Thus, DSP-based Plasminogen Activator Inhibitor 1-Targeted Fibrinolytic Therapy (PAI-1-TFT) of chronic infectious pleural injury in rabbits increases the efficacy of alteplase rendering ineffective doses of sctPA effective. PAI-1-TFT represents a novel, well-tolerated treatment of empyema that is amenable to clinical introduction. The chronic empyema model recapitulates increased resistance of advanced human empyema to fibrinolytic therapy, thus allowing for studies of muti-injection treatments.

Plasminogen activator inhibitor-1 (PAI-1) is an endogenous irreversible inhibitor of tissue-type (tPA) and urokinase (uPA) plasminogen activators. PAI-1-targeted fibrinolytic therapy (PAI-1-TFT) is designed to decrease the therapeutic dose of tPA and uPA, attenuating the risk of bleeding and other complications. Docking site peptide (DSP) mimics the part of the PAI-1 reactive center loop that interacts with plasminogen activators, thereby affecting the PAI-1 mechanism. We used DSP for PAI-1-TFT in two rabbit models: chemically induced pleural injury and Streptococcus pneumoniae induced empyema. These models feature different levels of inflammation and PAI-1 expression. PAI-1-TFT with DSP (2.0 mg/kg) converted ineffective doses of single chain (sc) tPA (72.5 µg/kg) and scuPA (62.5 µg/kg) into effective ones in chemically induced pleural injury. DSP (2.0 mg/kg) was ineffective in S. pneumoniae empyema, where the level of PAI-1 is an order of magnitude higher. DSP dose escalation to 8.0 mg/kg resulted in effective PAI-1-TFT with 0.25 mg/kg sctPA (1/8th of the effective dose of sctPA alone) in empyema. There was no increase in the efficacy of scuPA. PAI-1-TFT with DSP increases the efficacy of fibrinolytic therapy up to 8-fold in chemically induced (sctPA and scuPA) and infectious (sctPA) pleural injury in rabbits. PAI-1 is a valid molecular target in our model of S. pneumoniae empyema in rabbits, which closely recapitulates key characteristics of empyema in humans. Low-dose PAI-1-TFT is a novel interventional strategy that offers the potential to improve fibrinolytic therapy for empyema in clinical practice., (© 2021 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Plasminogen activator inhibitor 1 (PAI-1), which is elevated in numerous disease states, has been implicated as a stress-related protein involved in the pathogenesis of depression. We measured PAI-1 in the plasma of healthy and depressed individuals and assessed plasminogen activator (PA) expression and regulation by PAI-1 in cultured normal human astrocytes (NHA). Elevated plasma PAI-1 levels were found in depressed patients. Brain tissues from depressed individuals also showed stronger expression of hippocampal PAI-1 by confocal imaging in comparison to healthy individuals. Using a lipopolysaccharide-induced inflammatory model of depression in mice, we measured PAI-1 in murine plasma and brain, by ELISA and immunohistochemistry, respectively. Similar elevations were seen in plasma but not in brain homogenates of mice exposed to LPS. We further correlated the findings with depressive behavior. Ex vivo experiments with NHA treated with proinflammatory cytokines implicated in the pathogenesis of depression showed increased PAI-1 expression. Furthermore, these studies suggest that urokinase-type plasminogen activator may serve as an astrocyte PA reservoir, able to promote cleavage of brain-derived neurotrophic factor (BDNF) during stress or inflammation. In summary, our findings confirm that derangements of PAI-1 variably occur in the brain in association with the depressive phenotype. These derangements may impede the availability of active, mature (m)BDNF and thereby promote a depressive phenotype.

Unlabelled: A census is typically carried out for people across a range of geographical levels; however, microbial ecologists have implemented a molecular census of bacteria and archaea by sequencing their 16S rRNA genes. We assessed how well the census of full-length 16S rRNA gene sequences is proceeding in the context of recent advances in high-throughput sequencing technologies because full-length sequences are typically used as references for classification of the short sequences generated by newer technologies. Among the 1,411,234 and 53,546 full-length bacterial and archaeal sequences, 94.5% and 95.1% of the bacterial and archaeal sequences, respectively, belonged to operational taxonomic units (OTUs) that have been observed more than once. Although these metrics suggest that the census is approaching completion, 29.2% of the bacterial and 38.5% of the archaeal OTUs have been observed more than once. Thus, there is still considerable diversity to be explored. Unfortunately, the rate of new full-length sequences has been declining, and new sequences are primarily being deposited by a small number of studies. Furthermore, sequences from soil and aquatic environments, which are known to be rich in bacterial diversity, represent only 7.8 and 16.5% of the census, while sequences associated with host-associated environments represent 55.0% of the census. Continued use of traditional approaches and new technologies such as single-cell genomics and short-read assembly are likely to improve our ability to sample rare OTUs if it is possible to overcome this sampling bias. The success of ongoing efforts to use short-read sequencing to characterize archaeal and bacterial communities requires that researchers strive to expand the depth and breadth of this census., Importance: The biodiversity contained within the bacterial and archaeal domains dwarfs that of the eukaryotes, and the services these organisms provide to the biosphere are critical. Surprisingly, we have done a relatively poor job of formally tracking the quality of the biodiversity as represented in full-length 16S rRNA genes. By understanding how this census is proceeding, it is possible to suggest the best allocation of resources for advancing the census. We found that the ongoing effort has done an excellent job of sampling the most abundant organisms but struggles to sample the rarer organisms. Through the use of new sequencing technologies, we should be able to obtain full-length sequences from these rare organisms. Furthermore, we suggest that by allocating more resources to sampling environments known to have the greatest biodiversity, we will be able to make significant advances in our characterization of archaeal and bacterial diversity., (Copyright © 2016 Schloss et al.)

Fever is associated with improved survival during infection in endothermic and ectothermic species although the protective mechanisms are largely undefined. Previous studies indicate that fever-range thermal stress increases the binding activity of the L-selectin homing receptor in human or mouse leukocytes, thereby promoting trafficking to lymphoid tissues across high endothelial venules (HEV). Here, we examined the evolutionary conservation of thermal regulation of L-selectin-like adhesion. Leukocytes from animals representing four taxa of vertebrates (mammals, avians, amphibians, teleosts) were shown to mediate L-selectin-like adhesion under shear to MECA-79-reactive ligands on mouse HEV in cross-species in vitro adherence assays. L-selectin-like binding activity was markedly increased by fever-range thermal stress in leukocytes of all species examined. Comparable increases in L-selectin-like adhesion were induced by thermal stress, IL-6, or the IL-6/soluble IL-6 receptor fusion protein, hyper-IL-6. Analysis of the molecular basis of thermal regulation of L-selectin-like adhesion identified a common IL-6 trans-signaling mechanism in endotherms and ectotherms that resulted in activation of JAK/STAT signaling and was inhibited by IL-6 neutralizing antibodies or recombinant soluble gp130. Conservation of IL-6-dependent mechanisms controlling L-selectin adhesion over hundreds of millions of years of vertebrate evolution strongly suggests that this is a beneficial focal point regulating immune surveillance during febrile inflammatory responses.

The evolutionarily conserved febrile response has been associated with improved survival during infection in endothermic and ectothermic species although its protective mechanism of action is not fully understood. Temperatures within the range of physiologic fever influence multiple parameters of the immune response including lymphocyte proliferation and cytotoxic activity, neutrophil and dendritic cell migration, and production or bioactivity of proinflammatory cytokines. This review focuses on the emerging role of fever-range thermal stress in promoting lymphocyte trafficking to secondary lymphoid organs that are major sites for launching effective immune responses during infection or inflammation. Specific emphasis will be on the molecular basis of thermal control of lymphocyte-endothelial adhesion, a critical checkpoint controlling lymphocyte extravasation, as well as the contribution of interleukin-6 (IL-6) trans-signaling to thermal activities. New results are presented indicating that thermal stimulation of lymphocyte homing potential is evident in evolutionarily distant endothermic vertebrate species. These observations support the view that the evolutionarily conserved febrile response contributes to immune protection and host survival by amplifying lymphocyte access to peripheral lymphoid organs.

Purpose: To determine whether supplemental instruction offered to first-year medical students reduces the number of examination failures., Method: A student-run, optional, supplemental-instruction program called the Medical Scholars Program (MSP) was offered at no cost to all first-year students at the University of Southern California School of Medicine in 1994-95. Supplemental instruction was offered in a small-group format in biochemistry, gross anatomy, microanatomy, and physiology. Weekly two-hour sessions were conducted by second-year medical students during the first trimester of the year-1 curriculum. Mean test scores and failure rates for students considered academically at risk and those not at risk were compared between the class entering in 1994 and the classes matriculating during the preceding three years. At-risk students were defined as those with a total Medical College Admission Test score below 26 and a science grade-point average below 3.0. Comparisons were performed using two-tailed t-tests and chi-square tests., Results: Statistically significant increases in mean test scores were achieved on most examinations by the class exposed to the MSP. Failure rates for at-risk students decreased by 46% during the year the MSP was offered., Conclusion: Supplemental instruction can significantly improve student performance and therefore retention, particularly among at-risk students.

Background and Objectives: Early exposure to primary care is hypothesized as a means of reducing attrition in primary care specialty preference over the course of medical school. This study evaluated an elective preclinical primary care track that featured generalist instructors as role models and a community office-based experience in the second year of medical school., Methods: A total of 386 students from the University of Southern California graduating classes of 1991-1993 (both primary care track participants and nonparticipants) completed questionnaires on attitudes about primary care before and after the primary care track experiences. These pre- and post-second year data were linked with data for the same students from the Association of American Medical Colleges matriculation questionnaire and data on their specialty choices at graduation., Results: The primary care track, instituted during a period of declining interest in primary care among incoming students at our medical school, was not found to be associated with pre- and post-second year declines in participants' specialty preferences or attitudes toward primary care. Enrollment in the track and preclinical interest in primary care specialties were related to exogenous student characteristics (especially females). Enrollment was strongly predictive of primary care specialty choice at graduation but were not found to be related to students' anticipated debt levels for their medical education., Conclusion: Use of a primary care track in the preclinical years may help stem the decline in interest in primary care known to occur over the course of medical school. Coupled with a primary care specialty choice, participation in the track is clearly related to choice of a primary care specialty at graduation.

A major feature of a national survey of medical and surgical specialties is the development and application of an algorithm for classifying patient care services provided by physicians. The care classification reflects much of prevailing opinion regarding what constitutes primary and nonprimary care. The classification system provides a powerful tool for the analysis of patient care services, since it is based on conditions of access to care, the physician's role in providing the care, measures associated with continuity of care, and a proxy measure of comprehensiveness of care. Furthermore, it is based on the recordings by physicians of actual patient-encounter characteristics and is not operationally dependent on physician characteristics or propensities.

A nationwide study of 24 medical and surgical specialties has been conducted by the University of Southern California School of Medicine, Division of Research in Medical Education. This article is the first in a series reporting findings for general internal medicine and 10 subspecialties of internal medicine. Populations for these 11 specialties are defined and enumerated, and the specialties are compared in terms of demographic and geographic distribution. Practice comparisons are presented based on characteristics such as workload, allocation of professional time, location of encounters with patients, distribution of primary problem diagnoses, and projections of annual patient encounters. Forthcoming specialty-specific articles will present highly detailed information for general internal medicine and for the subspecialties of cardiology, gastroenterology, pulmonary disease, allergy, hematology, endocrinology, nephrology, medical oncology, rheumatology, and infectious diseases.

This paper reports a national study of physicians in 24 medical and surgical specialties, and reveals the opinions of neurosurgeons and their professional colleagues with regard to the adequacy of the supply of neurosurgical manpower. Among neurosurgeons, 30.4% believe the supply to be excessive, 60.1% think it is about right, 7.5% believe that there is a shortage, and 2.0% have no opinion. Neurologists' opinions do not differ significantly from those of neurosurgeons, but physicians and surgeons in 22 other specialties are significantly less likely to regard the supply as excessive and are more likely to perceive a shortage. Primary care physicians, as a group, are most likely to perceive a shortage, and least likely to indicate an excess. Among the 24 specialties studied, 9.3% of physicians believe the supply of neurosurgeons to be excessive, 55.1% think it is about right, 22.9% believe that there is a shortage, and 12.8% have no opinion.

A nationwide study of the practice activities of dermatologists reports that dermatology is a predominantly outpatient specialty, with 97% of patient encounter occurring outside of the hospital. The average dermatologist cares for approximately 7,000 patients a year and functions almost exclusively as a specialist, with only 2.2% of his cases related to nondermatologic problems. The dermatologist performs a type of primary care, however, with seven out of ten patients being self-referred. Eighty-seven percent of dermatologic encounters can be categorized into 25 disease conditions. This study serves to increase the understanding of how the dermatologist cares for his patients.

A nationwide study of practitioners in 24 medical and surgical specialties was conducted by the University of Southern California School of Medicine, Division of Research in Medical Education. In this second report of a series presenting findings for internal medicine, general internal medicine and 10 subspecialties of internal medicine are compared using a care classification scheme designed for the study. On the basis of characteristics of the individual patient encounter, this care classification scheme distinguishes several dimensions associated with the concept of primary care. Five empirically derived types of care rather than a simple "primary" or "non-primary" dichotomy are described, and the distributions of each type for the 11 subspecialties examined are noted. Types of care (according to the care classification) are examined by the time per patient, the complexity of physician services, the severity and chronicity of problems, and the degree of specialization associated with providing different types of care. Estimates of the number of annual encounters, and the number of annual encounters for three of the five types of care, with the proportion of each accounted for by each subspecialty, are given.

The Division of Research in Medical Education and of the University of Southern California, with the cooperation and assistance of the American Association of Neurological Surgeons and the Congress of Neurological Surgeons, has conducted a national study of the professional activities of neurological surgeons in the United States. One of a series of 24 surveys of medical and surgical specialties, the survey obtained information on patient workloads, the allocation of physician time, the characteristics of patients and the circumstances under which they were seen, patient diagnoses, and the care that was provided--including whether an operation was performed. This paper provides a selection of the findings deemed most relevant to manpower issues in neurosurgery. A later paper will examine regional differences in patient care, including the frequency with which selected surgical procedures are used for different clinical conditions.

The survey instrument used in the national study of physician activities conducted by the University of Southern California, Division of Research in Medical Education, is a log-diary in which physicians kept a record of their actual professional activities. The log-diary focused on use of physician time and patient encounters and employed numerical coding of activities and patient encounters in a highly structured format. Compared with instruments used in similar studies, this log-diary appears to gather a greater breadth and depth of information about physician practice patterns.

Results of a national survey of nonfederal otorhinolaryngologist regarding their practices provide the following portrait of the typical physician who specializes in otorhinolaryngology: male, between 35 and 45 years old, engaged in solo practice in a metropolitan area in the southern part of the country. He works a 46-hour week, devoting most of his time to patient care. During a typical week, he sees 113 patients, mostly outside the hospital. Half of his patients are male; although their average age is 35, one fourth of his patients are under 15 years. Every third patient is new to him; every other patient has been referred. He spends almost 15 minutes with each patient, many of whom he is seeing on a continuous basis for a problem involving the ear. He prescribes medications in roughly half of all encounters; every tenth patient requires surgery. He rates the majority of the problems he encounters as chronic, and of minor to moderate severity and urgency--for which he provides services of limited complexity or less. He seldom refers his patients.

The University of Southern California is conducting a national survey of physicians involving the collection and analysis of detailed data on the activities and practice characteristics of generalists, medical specialists, and surgical specialists of different types. This is the first of a series of reports on the survey and provides an overview of the survey's background, purposes, and general research methods. Basic features of the research methods include the development of a survey instrument capable of obtaining different types of practice data from physicians in most specialties and practice arrangements, the sampling of physician population to ensure that sufficient data are obtained from physicians in most specialties and practice arrangements, and the creation and application of a scheme for classifying patient-care services provided by physicians along dimensions related to primary care.