Predicting bat colony survival under controls targeting multiple transmission routes of white-nose syndrome.

White-nose syndrome (WNS) is a lethal infection of bats caused by the psychrophilic fungus Pseudogymnoascus destructans (Pd). Since the first cases of WNS were documented in 2006, it is estimated that as many as 5.5million bats have succumbed in the United States-one of the fastest mammalian die-offs due to disease ever observed, and the first known sustained epizootic of bats. WNS is contagious between bats, and mounting evidence suggests that a persistent environmental reservoir of Pd plays a significant role in transmission as well. It is unclear, however, the relative contributions of bat-to-bat and environment-to-bat transmission to disease propagation within a colony. We analyze a mathematical model to investigate the consequences of both avenues of transmission on colony survival in addition to the efficacy of disease control strategies. Our model shows that selection of the most effective control strategies is highly dependent on the primary route of WNS transmission. Under all scenarios, however, generalized culling is ineffective and while targeted culling of infected bats may be effective under idealized conditions, it primarily has negative consequences. Thus, understanding the significance of environment-to-bat transmission is paramount to designing effective management plans.

A decision framework for prioritizing multiple management actions for threatened marine megafauna.

Resources for conserving biodiversity are invariably insufficient. This situation creates the need for transparent, systematic frameworks to help stakeholders prioritize the allocation of resources across multiple management actions. We developed a novel framework that explicitly prioritizes actions to minimize the impacts of several threats across a species' range. The framework uses a budget constraint and maximizes conservation outcomes from a set of management actions, accounting for the likelihood of the action being successfully applied and accepted by local and Indigenous communities. This approach is novel in that it integrates local knowledge and expert opinion with optimization software, thereby minimizing assumptions about likelihood of success of actions and their effectiveness. To test the framework, we used the eastern Gulf of Carpentaria and Torres Strait population of the flatback turtle, Natator depressus, as a case study. This approach allowed the framework to be applied in a data-poor context, a situation common in conservation planning. The framework identified the best set of actions to maximize the conservation of flatback eggs for scenarios with different budgets and management parameters and allowed comparisons between optimized and preselected scenarios. Optimized scenarios considered all implementable actions to explore how to best allocate resources with a specified budget and focus. Preselected scenarios were used to evaluate current allocations of funds and/or potential budget allocations suggested by different stakeholders. Scenarios that used a combination of aerial and ground strategies to reduce predation of eggs performed better than scenarios that focused only on reducing harvest of eggs. The performances of optimized and preselected scenarios were generally similar among scenarios that targeted similar threats. However, the cost-effectiveness of optimized scenarios was usually higher than that of preselected scenarios, demonstrating the value of conducting a systematic optimization approach. Our method provides a foundation for more effective conservation investments and guidance to prioritize actions within recovery plans while considering the sociopolitical and cultural context of decisions. The framework can be adapted easily to a wide range of species, geographical scales, and life stages.

(2S,4E)-2-Hydroxy-4-octen-3-one, a Male-Produced Attractant Pheromone of the Cerambycid Beetle Tylonotus bimaculatus.

We report the identification of a novel pheromone structure from males of the cerambycid beetle Tylonotus bimaculatus Haldeman (Cerambycinae: Hesperophanini), a species native to eastern North America. Volatiles collected from adult males contained (2S,4E)-2-hydroxyoct-4-en-3-one (71%), (3R,4E)-3-hydroxyoct-4-en-2-one (15%), (E)-4-octen-2,3-dione (13%), and 2,3-octanedione (1.5%). Four independent field bioassays with synthetic compounds confirmed that adults of both sexes were attracted by the racemate of the major component, (E)-2-hydroxyoct-4-en-3-one. No other cerambycid species were attracted in significant numbers. Attraction of both sexes is consistent with the male-produced pheromones of many other species in the subfamily Cerambycinae, but T. bimaculatus is unusual in having a pheromone chemistry that is so far unique among species in that subfamily.

The population ecology of infectious diseases: pertussis in Thailand as a case study.

Many of the fundamental concepts in studying infectious diseases are rooted in population ecology. We describe the importance of population ecology in exploring central issues in infectious disease research including identifying the drivers and dynamics of host-pathogen interactions and pathogen persistence, and evaluating the success of public health policies. The use of ecological concepts in infectious disease research is demonstrated with simple theoretical examples in addition to an analysis of case notification data of pertussis, a childhood respiratory disease, in Thailand as a case study. We stress that further integration of these fields will have significant impacts in infectious diseases research.

Variance in Bacillus anthracis virulence assessed through Bayesian hierarchical dose-response modelling.

AIMS: To develop a predictive dose-response model for describing the survival of animals exposed to Bacillus anthracis to support risk management options. METHODS AND RESULTS: Dose-response curves were generated from a large dose-mortality data set (>11,000 data points) consisting of guinea pigs exposed via the inhalation route to 76 different product preparations of B. anthracis. Because of the predictive nature of the Bayesian hierarchical approach (BHA), this method was used. The utility of this method in planning for a variety of scenarios from best case to worst case was demonstrated. CONCLUSIONS: A wide range of expected virulence was observed across products. Median estimates of virulence match well with previously published statistical estimates, but upper bound values of virulence are much greater than previous statistical estimates. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first meta-analysis in open literature to estimate the dose-response relationship for B. anthracis from a very large data set, generally a rare occurrence for highly infectious pathogens. The results are also the first to suggest the extent of variability, which is contributed by product preparation and/or dissemination methods, information needed for health-based risk management decisions in response to a deliberate release. A set of possible benchmark values produced through this analysis can be tied to the risk tolerance of the decision-maker or available intelligence. Further, the substantial size of the data set led to the ability to assess the appropriateness of the assumed distributional form of the prior, a common limitation in Bayesian analysis.

Brain death and the cervical spinal cord: a confounding factor for the clinical examination.

STUDY DESIGN: This study is a systematic review. OBJECTIVES: Brain death (BD) is a clinical diagnosis, made by documenting absent brainstem functions, including unresponsive coma and apnea. Cervical spinal cord dysfunction would confound clinical diagnosis of BD. Our objective was to determine whether cervical spinal cord dysfunction is common in BD. METHODS: A case of BD showing cervical cord compression on magnetic resonance imaging prompted a literature review from 1965 to 2008 for any reports of cervical spinal cord injury associated with brain herniation or BD. RESULTS: A total of 12 cases of brain herniation in meningitis occurred shortly after a lumbar puncture with acute respiratory arrest and quadriplegia. In total, nine cases of acute brain herniation from various non-meningitis causes resulted in acute quadriplegia. The cases suggest that direct compression of the cervical spinal cord, or the anterior spinal arteries during cerebellar tonsillar herniation cause ischemic injury to the cord. No case series of brain herniation specifically mentioned spinal cord injury, but many survivors had severe disability including spastic limbs. Only two pathological series of BD examined the spinal cord; 56-100% of cases had upper cervical spinal cord damage, suggesting infarction from direct compression of the cord or its arterial blood supply. CONCLUSIONS: Upper cervical spinal cord injury may be common after brain herniation. Cervical spinal cord injury must either be ruled out before clinical testing for BD, or an ancillary test to document lack of brainstem blood flow is required in all cases of suspected BD. BD may not be a purely clinical diagnosis.

Effects of Computerized Cognitive Training on Gait Speed in Community Dwelling Older Adults, A Pilot Study.

BACKGROUND: In older adults declines in gait speed have been identified as predictors of functional decline and have been found in those with cognitive dysfunction. Cognitive training interventions that emphasize addressing executive function (EF) have resulted in a transfer effect from training cognitive processes into improved function. However research examining the effects of an EF specific computerized cognitive training (CCT) program on gait speed (GS) is limited. OBJECTIVES: To compare the effects of a six week EF specific CCT program on GS in community dwelling older adults using a pretest/posttest experimental design with subgroup comparisons based on a cutoff GS of 1.0m/s. SETTING: Home based. PARTICIPANTS: Forty independent living older adults (>65 years) without diagnosed cognitive impairment participated in either the intervention or control groups. INTERVENTION: A six week long progressively challenging EF focused CCT program was performed at home. MEASUREMENTS: Demographic variables, cognitive function (Trail-Making Test Part B) and GS were measured at baseline at week 7. Between group comparisons were completed for the whole sample initially with subgroup comparisons performed based on participants' initial GS (Slow walkers: GS<1.0m/s; Fast Walkers: GS>1.0m/s). RESULTS: No differences in GS were found for the whole population, but subgroup analyses restricted to slow walkers demonstrated a statistically significant improvement in GS after 6 weeks of CCT (µ =0.33 m/s, p = 0.03). Other outcomes measures were not statistically different at posttest. CONCLUSIONS: Older adults who walk at speeds <1.0m/s may benefit from a progressively challenging CCT program when self-administered in the home.

The role of interconnectivity in control of an Ebola epidemic.

Several West African countries - Liberia, Sierra Leone and Guinea - experienced significant morbidity and mortality during the largest Ebola epidemic to date, from late 2013 through 2015. The extent of the epidemic was fueled by outbreaks in large urban population centers as well as movement of the pathogen between populations. During the epidemic there was no known vaccine or drug, so effective disease control required coordinated efforts that include both standard medical and community practices such as hospitalization, quarantine and safe burials. Due to the high connectivity of the region, control of the epidemic not only depended on internal strategies but also was impacted by neighboring countries. In this paper, we use a deterministic framework to examine the role of movement between two populations in the overall success of practices designed to minimize the extent of Ebola epidemics. We find that it is possible for even small amounts of intermixing between populations to positively impact the control of an epidemic on a more global scale.

The Impact of a Home-Based Computerized Cognitive Training Intervention on Fall Risk Measure Performance in Community Dwelling Older Adults, a Pilot Study.

OBJECTIVES: Cognitive intervention studies have reported improvements in various domains of cognition as well as a transfer effect of improved function post training. Despite the availability of web based cognitive training programs, most intervention studies have been performed under the supervision of researchers. Therefore, the purpose of this study was to first, examine the feasibility of a six week home based computerized cognitive training (CCT) program in a group of community dwelling older adults and, second, to determine if a CCT program which focused on set shifting, attention, and visual spatial ability impacted fall risk measure performance. DESIGN: This pilot study used a pretest/posttest experimental design with randomization by testing site to an intervention or control group. PARTICIPANTS: Community dwelling older adults (mean age = 74.6 years) participated in either the control (N=25) or the intervention group (N=19). INTERVENTION: Intervention group subjects participated in 6 weeks of home based CCT 3x/week for an average of 23 minutes/session, using an online CCT program. MEASUREMENTS: Comparisons of mean scores on three measures of physical function (usual gait speed, five times sit to stand, timed up and go) were completed at baseline and week 7. RESULTS: Following the completion of an average of 18 sessions of CCT at home with good adherence (86%) and retention (92%) rates, a statistically significant difference in gait speed was found between groups with an average improvement of 0.14 m/s in the intervention group. CONCLUSION: A home based CCT program is a feasible approach to targeting cognitive impairments known to influence fall risk and changes in gait in older adults.

Using age-stratified incidence data to examine the transmission consequences of pertussis vaccination.

Pertussis is a highly infectious respiratory disease that has been on the rise in many countries worldwide over the past several years. The drivers of this increase in pertussis incidence remain hotly debated, with a central and long-standing hypothesis that questions the ability of vaccines to eliminate pertussis transmission rather than simply modulate the severity of disease. In this paper, we present age-structured case notification data from all provinces of Thailand between 1981 and 2014, a period during which vaccine uptake rose substantially, permitting an evaluation of the transmission impacts of vaccination. Our analyses demonstrate decreases in incidence across all ages with increased vaccine uptake - an observation that is at odds with pertussis case notification data in a number of other countries. To explore whether these observations are consistent with a rise in herd immunity and a reduction in bacterial transmission, we analyze an age-structured model that incorporates contrasting hypotheses concerning the immunological and transmission consequences of vaccines. Our results lead us to conclude that the most parsimonious explanation for the combined reduction in incidence and the shift to older age groups in the Thailand data is vaccine-induced herd immunity.

Survival distribution in breast cancer.

It has been stated that breast cancer survival rates follow an exponential distribution. This would mean that the mortality rate is constant. Survival distribution was analyzed by the clinical life table method in one series of 10,752 patients and in another of 656 patients followed up to 8 and 18 years, respectively. Part of the larger series' table is (table: see text). Necessarily, clinical survival data are censored progressively. These kinds of data are analyzed best by examining the hazard function, which is the instantaneous death rate, or force of mortality. If an exponential distribution described survival in breast cancer correctly, the hazard function would be constant. These data clearly are not consistent with an exponential distribution, as the hazard function decreases. The survival distribution calculated from these data shows that the chance of dying of cancer decreases the longer a patient survives. This is more optimistic and consistent with clinical experience than is the exponential distribution.

Ergotism.

Severe extremity ischemia developed in four patients who had ingested methysergide maleate or ergot for the relief of headache. Symptoms involved the upper extremity in two patients and the lower extremity in two. Spontaneous reversal of the ischemic picture was obtained by simple discontinuation of ergot in most instances, although intra-arterial vasodilators were used in one case. Angliography disclosed arterial spasm and was a useful adjunct in confirming the cause of ischemia in each of the patients. It was especially useful when a history or ergot ingestion was not immediately available.

Functional longevity of intraperioneal drains: an experimental evaluation.

Various types of drains were inserted into the peritoneal cavity of twenty-eight dogs. After one to seven days, all drains failed to show the presence of 200 cc of colored fluid injected intraperitoneally. On autopsy, all tubes were surrounded and occluded by omentum.

Long-term follow-up of treated dental phobics.

Behavioural treatment programmes have been shown repeatedly to be effective in alleviating dental anxiety but few studies have provided long-term follow-ups. In this study, dentally anxious Ss who had completed a 4-session behavioural group programme were followed up for periods between 1 and 4 years after successful completion of treatment. It was hypothesized that dental visit satisfaction would be associated with regular dental attendance. 88% of Ss contacted agreed to cooperate; of these, 70% were still maintaining regular check-ups. There were no differences between regular and irregular attenders in terms of age, gender, education, marital status, degree of pre-treatment avoidance or time elapsed since completion of the programme. However, Ss who did not see their dentists regularly were more likely to have shown higher levels of anxiety immediately after completing the programme, less concordance between the subjective and overt behavioural aspects of anxiety and to have experienced more invasive than non-invasive procedures than the others. It was argued that dentally anxious individuals are not a homogeneous group and that a better understanding of their individual differences would lead to the development of more efficacious treatment procedures.

Intra-abdominal infection following combined spleen-colon trauma.

The reality of late overwhelming post-splenectomy sepsis in adults as well as children has led to more frequent attempts at splenic salvage following splenic trauma. Less attention has been paid to early septic postoperative complications in the splenectomized patient. Associated colon injury has been believed to be a relative contraindication to splenic conservation. If splenectomy enhances the chance of early postoperative infection, then associated colon injury should be an indication for splenic salvage One hundred sixty one patients who had either splenic trauma (58), colon trauma (90), or combined spleen-colon trauma (13) were studied. All patients with splenic trauma had a splenectomy. There was a significantly higher incidence of intra-abdominal sepsis requiring reoperation in the spleen-colon patients (46.7%) than in either of the other groups (spleen = 5.7%, colon = 8.9%, P less than .002 for both comparisons). It is concluded that splenectomy enhances infection in the early postoperative period. When possible, combined spleen-colon trauma should be an indication rather than a contraindication for splenic salvage.

Role of antibiotic prophylaxis in surgery for nonperforated appendicitis.

This report examines the efficacy of preoperative antibiotics in cases of nonperforated appendicitis. The charts of 61 patients who had an operative and pathologic diagnosis of acute nonperforated appendicitis were reviewed. Thirty-one patients received preoperative cephalosporins, and in one patient (3.2%) a subsequent wound infection developed. Of 30 patients who did not receive preoperative antibiotics, four (13.2%) patients developed septic complications. The difference in postoperative septic complications between these groups is not statistically significant (P = .3310). Preoperative prophylaxis with cephalosporins in cases of nonperforated appendicitis is not indicated.

Giant recurrent desmoid tumor: a case report.

A case of giant recurrent intra-abdominal desmoid tumor is presented. A history of childbirth, antecedent surgery, multiple episodes of recurrence, resistance to excisional and radiation therapy, represent common features of desmoid tumors. The size of the recurrence (15.4 kg), the intra-abdominal presentation of the tumor, involvement of the chest wall and focal infiltration of the small bowel are unusual features of this case.

Reoperation for sepsis.

A retrospective study of 50 patients undergoing reoperation for sepsis was performed to evaluate the ability of commonly available clinical and laboratory tests to predict the findings at reoperation and the outcome after operation. The influence of multiple organ failure on these parameters was also studied. No laboratory finding helped to predict operative findings. Computed tomographic scanning (80% accurate) was the most helpful radiographic procedure. A low total lymphocyte count and a high serum creatinine level both predicted a fatal outcome. No single organ failure or combination predicted a positive reexploration. Infection was found in 75 per cent of patients with multiple organ failure and 79 per cent of patients who did not have this syndrome. Patients having three-organ failure did have a significantly higher mortality. The mortality of a negative reexploration was 18.2 per cent, slightly lower than the 28.2 per cent mortality of patients with a positive exploration. No patient without organ failure died. The authors conclude that laboratory tests are not helpful in predicting the presence of infection on reexploration, that the decision to reoperate is one based primarily on clinical judgment, and that if reoperation is performed before the development of organ failure, the risk associated with a negative exploration is worth taking.

Penetrating injuries to the colon.

In planning the management of a colonic injury, several factors must be taken into account, including the age of the patient, the cause of the wound, the time lapse from injury to operation, area and the type of wound, the amount of fecal soilage, and the number and extent of associated injuries. For extensive wounds with associated injuries, fecal contamination of the abdomen, or delay from injury to treatment, a two-stage procedure is preferred. Primary closure or primary resection is the preferred treatment for right colon injuries, depending on the severity of the injury. Resection and anastomosis should not be performed in the left colon without a diverting colostomy. Exteriorization is a satisfactory procedure for major colon injury; however, exteriorization and repair have a higher associated complication rate than exteriorization alone. Primary repair is a safe and acceptable procedure, irrespective of the site of injury. Indications for primary repair may, in the future, be expanded to include those wounds presently being treated by exteriorization.