Conservation overstretch and long-term decline of wildlife and tourism in the Central African savannas

When in 2010 the world's governments pledged to increase protected area coverage to 17% of the world's land surface, several Central African countries had already set aside 25% of their northern savannas for conservation. To evaluate the effectiveness of this commitment, we analyzed the results of 68 multispecies surveys conducted in the seven main savanna national parks in Central Africa (1960-2017). We also assembled information on potential drivers of large herbivore population trends (rainfall and number of rangers) and on tourist numbers and revenues. In six out of the seven parks, wild large herbivore populations declined dramatically over time, livestock numbers increased severalfold, and tourism, the pillar under a once thriving local wildlife industry, collapsed. Zakouma National Park (Chad) stood out because its large herbivore populations increased, an increase that was positively correlated with rainfall and number of rangers (a proxy for management inputs). With increasing insecurity and declining revenues, governments find themselves confronted with too few resources to protect vast areas. To deal with this conversation overstretch, we propose to extend the repeatedly promoted solutions--scaled up funding, enhanced management--with a strategic retreat, focusing scarce resources on smaller areas to save wildlife in the Central African savannas.

Network analyses to quantify effects of host movement in multilevel disease transmission models using foot and mouth disease in Cameroon as a case study

The dynamics of infectious diseases are greatly influenced by the movement of both susceptible and infected hosts. To accurately represent disease dynamics among a mobile host population, detailed movement models have been coupled with disease transmission models. However, a number of different host movement models have been proposed, each with their own set of assumptions and results that differ from the other models. Here, we compare two movement models coupled to the same disease transmission model using network analyses. This application of network analysis allows us to evaluate the fit and accuracy of the movement model in a multilevel modeling framework with more detail than established statistical modeling fitting methods. We used data that detailed mobile pastoralists’ movements as input for 100 stochastic simulations of a Spatio-Temporal Movement (STM) model and 100 stochastic simulations of an Individual Movement Model (IMM). Both models represent dynamic movement and subsequent contacts. We generated networks in which nodes represent camps and edges represent the distance between camps. We simulated pathogen transmission over these networks and tested five network metrics–strength, betweenness centrality, three-step reach, density, and transitivity–to determine which could predict disease simulation outcomes and thereby be used to correlate model simulation results with disease transmission simulations. We found that strength, network density, and three-step reach of movement model results correlated with the final epidemic size of outbreak simulations. Betweenness centrality only weakly correlated for the IMM model. Transitivity only weakly correlated for the STM model and time-varying IMM model metrics. We conclude that movement models coupled with disease transmission models can affect disease transmission results and should be carefully considered and vetted when modeling pathogen spread in mobile host populations. Strength, network density, and three-step reach can be used to evaluate movement models before disease simulations to predict final outbreak sizes. These findings can contribute to the analysis of multilevel models across systems.

Epidemics of infectious disease vary geographically and vary through time. A large part of this variation is caused by movement of individuals who are susceptible to the disease or infected with the disease. To study how movement affects epidemics, researchers often combine movement models with transmission models. However, multiple movement models have been proposed, and their effect on infectious disease model output is not well understood. Here, we combine two different movement models that we developed to represent mobile pastoralists in the Far North Region, Cameroon, with the same disease transmission model. We use network metrics to test how different movement models can affect the output of the disease transmission model. We found that three metrics could be applied to movement model output in order to predict epidemic model output. We conclude that movement models coupled with disease transmission models can affect disease transmission results and should be carefully considered and vetted when modeling epidemics.

Modeling the role of carrier and mobile herds on foot-and-mouth disease virus endemicity in the Far North Region of Cameroon

Foot and mouth disease virus (FMDV) is an RNA virus that infects cloven-hoofed animals, often produces either epidemic or endemic conditions, and negatively affects agricultural economies worldwide. FMDV epidemic dynamics have been extensively studied, but understanding of drivers of disease persistence in areas in which FMDV is endemic, such as most of sub-Saharan Africa, is lacking. We present a spatial stochastic model of disease dynamics that incorporates a spatial transmission kernel in a modified Gillespie algorithm, and use it to evaluate two hypothesized drivers of endemicity: asymptomatic carriers and the movement of mobile herds. The model is parameterized using data from the pastoral systems in the Far North Region of Cameroon. Our computational study provides evidence in support of the hypothesis that asymptomatic carriers, but not mobile herds, are a driver of endemicity.

Network analyses of transhumance movements and simulations of foot-and-mouth disease virus transmission among mobile livestock in Cameroon

Foot-and-mouth disease (FMD) affects cloven-hoofed livestock and agricultural economies worldwide. Analyses of the 2001 FMD outbreak in the United Kingdom informed how livestock movement contributed to disease spread. However, livestock reared in other locations use different production systems that might also influence disease dynamics. Here, we investigate a livestock production system known as transhumance, which is the practice of moving livestock between seasonal grazing areas. We built mechanistic models using livestock movement data from the Far North Region of Cameroon. We represented these data as a dynamic network over which we simulated disease transmission and examined three questions. First, we asked what were characteristics of simulated FMDV transmission across a transhumant pastoralist system. Second, we asked how simulated FMDV transmission across a transhumant pastoralist system differed from transmission across this same population held artificially stationary, thereby revealing the effect of movement on disease dynamics. Third, we asked if disease simulations on well-studied theoretical networks are similar to disease simulations on this empirical dynamic network. The results show that the empirical dynamic network was sparsely connected except for an eight-week period in September and October when pastoralists move from rainy season to dry season grazing areas. The mean epidemic size across all 3,744 simulations was 99.9% and the mean epidemic duration was 1.45 years. Disease simulations across the static network showed a smaller mean epidemic size (27.6%) and a similar epidemic duration (1.5 years). Epidemics simulated on theoretical networks showed similar final epidemic sizes (100%) and different mean durations. Our simulations indicate that transhumant livestock systems have the potential to host FMDV outbreaks that affect almost all livestock and last longer than a year. Furthermore, our comparison of empirical and theoretical networks underscores the importance of using empirical data to understand the role of mobility in the transmission of infectious diseases.

Molecular Epidemiology of Foot-and-Mouth Disease Virus in the Context of Transboundary Animal Movement in the Far North Region of Cameroon

Transboundary movement of animals is an important mechanism for foot-and-mouth disease virus (FMDV) spread in endemic regions, such as Cameroon. Several transboundary animal trade routes cross the Far North Region of Cameroon, and cattle moved on foot along these routes often come in contact with native (sedentary and transhumant) herds. The purpose of this study was to investigate the role of transboundary trade cattle in the epidemiology of FMDV in the Far North Region of Cameroon. A total of 582 oropharyngeal fluid (OPF) samples were collected from asymptomatic transboundary trade cattle at official border check points and 57 vesicle epithelial tissues were collected from clinically affected native cattle in the Far North Region of Cameroon during 2010-2014. Viral protein 1 (VP1) coding sequences were obtained from 6 OPF samples from transboundary cattle (4 serotype O, 2 serotype SAT2) and 19 epithelial tissue samples from native cattle (7 serotype O, 3 serotype SAT2, 9 serotype A). FMDV serotype O viruses belonged to two topotypes (East Africa-3 and West Africa), and phylogenetic analyses suggested a pattern of continuous transmission in the region. Serotype SAT2 viruses belonged to a single topotype (VII), and phylogenetic analysis suggested a pattern of repeated introductions of different SAT2 lineages in the region. Serotype A viruses belonged to topotype AFRICA/G-IV, and the pattern of transmission was unclear. Spearman rank correlation analysis of VP1 coding sequences obtained in this study from transboundary and native cattle showed a positive correlation between genetic distance and time for serotype O (ρ = 0.71, p = 0.003) and between genetic distance and geographic distance for serotype SAT2 (ρ = 0.54, p = 0.1). These data suggest that transboundary trade cattle participate in the transmission of FMDV in the Far North Region of Cameroon, however the dynamics and direction of transmission could not be determined in this study. Results of this study contribute to the understanding of transboundary FMDV epidemiology in Central Africa and will help to inform control programs in Cameroon and in the region.

Risk of environmental exposure to small coccidia from wild canid feces in rural Ohio

OBJECTIVE To determine the extent of environmental exposure to heteroxenous coccidia from wild canid feces in southeastern Ohio. SAMPLE 285 presumed wild canid fecal samples collected across an ecological system in southeastern Ohio. PROCEDURES Morphological classification and molecular analysis were used to determine the canid genus for collected fecal samples. Microscopic and molecular analysis were used to detect coccidian oocysts and DNA. Several variables were analyzed for associations with coccidian DNA detection or prevalence. RESULTS Coccidian DNA was detected in 51 of 285 (17.9%) fecal samples. Of those positive samples, 1% (95% confidence interval, 0.4% to 3%) had positive results for Hammondia heydorni and none had positive results for Neospora caninum, for an estimated environmental N caninum prevalence of 0% (95% confidence interval, 0% to 7%)/1-km² hexagonal area evaluated. Morphological classification revealed that 78.9% (225/285) of fecal samples were from coyotes and 17.2% (49/285) were from foxes. No difference in proportions of coccidian DNA-positive fecal samples was identified among canid species. Environmental temperature and fecal freshness were associated with coccidian DNA detection. Land use type, relative canid density, and cattle density were not associated with the prevalence of coccidian DNA-positive samples. CONCLUSIONS AND CLINICAL RELEVANCE The low prevalence of coccidia shed in wild canid feces in this study, including the estimated 0% environmental prevalence of N caninum, suggested that the role of the oocyst environmental phase in coccidia transmission to ruminants is likely minor in rural southeastern Ohio.

Host species heterogeneity in the epidemiology of Nesopora caninum

Pathogen transmission across species drives disease emergence; however, mechanisms by which multi-host pathogens cross species boundaries are not well identified. This knowledge gap prevents integrated and targeted control in an epidemiologically continuous ecosystem. Our goal is to describe the impact of host species heterogeneity on the epidemiology of Neospora caninum circulating between livestock and wildlife in southeastern Ohio. We collected biological samples from Père David’s deer (Elaphurus davidianus) located at an outdoor wildlife conservation center; from cattle raised at farms adjacent to the center; and from wild white-tailed deer that roamed across farm and center boundaries. We designed nested infectious disease models of competing hypotheses about transmission and used collected data to fit the models, thereby estimating important immunological and transmission quantities which describe the species-specific contribution to the persistence of this pathogen in the community. We applied these data and models to suggest appropriate species-specific disease control methods. Results show that immunity in cattle and Pére David’s deer wanes over time, while in white-tailed deer immunity appears to be lifelong. Transmission quantities for cattle were estimated at values below the threshold for an outbreak (R_t < 1), meaning that chains of transmission are not maintained within this population and infections must occur due to reintroduction from an outside source. Pére David’s deer and white-tailed deer both could maintain continuous chains of transmission within their group (R_t > 1). Therefore, we propose that control of contact with outside sources will be useful for disease control in cattle; boosting immunity with vaccines might be an avenue to prevent infection in cattle and Père David’s deer. White-tailed deer are a potential maintenance host for infection and require further study to determine optimal control methods. Community-level investigations like this allow us to better evaluate heterogeneities in transmission processes that ultimately guide targeted control.

Pregnancy in Lung Transplant Recipients

Eight female lung transplant recipients, all of whom became pregnant after transplant, were reported to the National Transplantation Pregnancy Registry from US transplant centers. Outcomes of the 8 pregnancies were 4 live births, 3 therapeutic abortions, and 1 spontaneous abortion. Three of the 4 newborns were premature, with low birth weight (< 2500 grams). Rejection during pregnancy occurred in 3 pregnancies (38%). All 8 transplant recipients reported at least 1 complication during pregnancy, including shortness of breath, rejection, and infection. Two of the 4 deliveries were by cesarean section. At follow-up, all children were developing well with no residual problems. Female lung transplant recipients may face higher risks during pregnancy than other solid organ transplant recipients.

Recurrent Aortic Angiosarcoma

Primary aortic tumors are rare; only 86 cases of primary aortic angiosarcoma have been reported since its first description in 1873. The diagnosis of aortic angiosarcoma is usually confirmed by postoperative pathologic examination or postmortem study. The authors present a case of primary aortic angiosarcoma with postresection recurrence.

[Characterization of the seriously injured cyclist : An evaluation of the injury and treatment focus areas of 2817 patients]

BACKGROUND

Transport statistics classify bicyclists in a separate road user collective. For medical reasons, this differentiation is applied as well. Much literature is published in this field. Nevertheless there is a lack of literature regarding the overall injury patterns in a defined injury severity collective. Most literature is about isolated injured regions in combination with a heterogeneous injury severity. Further parameters, such as injury patterns, epidemiological aspects, treatment focal points and characteristic outcomes, have also been studied. The aim of the present study was to evaluate and characterize injury patterns in a standardized and representative collective of severely injured bicyclists. Methods We analysed data from the Traumaregister DGU® from 2002 to 2010. In total, 2817 severely injured (ISS ≥ 9 and additional intensive/intermediate care unit) bicyclists were included. The primary endpoint was evaluation of injury patterns and injury focal points. In addition to that we analysed parameters like epidemiological aspects, circumstances of accident, treatment focal points and outcome.

RESULTS

The mean age was 50.3 ± 20.9 years. Males accounted for 68.9 % (n = 1940). The mean ISS was 23.7 ± 12.6. The mean AIS regions were the head 71.9 % (n = 2025), the chest with 44.9 % (n = 1264) and the upper extremities 33.6 % (947). In 68.2 % of all cases an ISS ≥ 9 was achieved by a traumatic brain injury; 21.1 % of all cases were mono-injuries. A characteristic distribution of age and a characteristic prevalence of the accidents in relation to the weekday and the month could be shown.

CONCLUSION

The present study analysed the largest ever published collective of severely injured bicyclists. Traumatic brain injury could clearly be shown as the main injury in this collective. Moreover, one of five cases achieved the state "severely injured" due to mono-injury.

Neighborhood diversity of potentially pathogenic bacteria in drinking water from the city of Maroua, Cameroon

This study examined the spatial variation of potential gastrointestinal pathogens within drinking water sources and home storage containers in four neighborhoods in Maroua, Cameroon. Samples were collected from source (n = 28) and home containers (n = 60) in each study neighborhood. Pathogen contamination was assessed using quantitative polymerase chain reaction, targeting Campylobacter spp., Shiga toxin producing Escherichia coli (virulence genes, stx1 and stx2), and Salmonella spp. Microbial source tracking (MST) targeted three different host-specific markers: HF183 (human), Rum2Bac (ruminant) and GFD (poultry) to identify contamination sources. Staphylococcus aureus and the tetracycline-resistance gene (tetQ) were assessed to measure human hand contact and presence of antibiotic-resistant bacteria. Pathogen/MST levels were compared statistically and spatially, and neighborhood variation was compared with previously collected demographic information. All the test fecal markers and pathogens (except Arcobacter) were detected in home and source samples. Two neighborhoods tested positive for most pathogens/MST while the others only tested positive for one or two. Spatial variation of pathogens/MST existed between sources, storage containers, and neighborhoods. Differing population density and ethno-economic characteristics could potentially explain variation. Future research should explore the influence of demographic and ethno-economic factors on water quality during microbial risk assessments in urban Africa.

Meta-studies in land use science: Current coverage and prospects

Land use science has traditionally used case-study approaches for in-depth investigation of land use change processes and impacts. Meta-studies synthesize findings across case-study evidence to identify general patterns. In this paper, we provide a review of meta-studies in land use science. Various meta-studies have been conducted, which synthesize deforestation and agricultural land use change processes, while other important changes, such as urbanization, wetland conversion, and grassland dynamics have hardly been addressed. Meta-studies of land use change impacts focus mostly on biodiversity and biogeochemical cycles, while meta-studies of socioeconomic consequences are rare. Land use change processes and land use change impacts are generally addressed in isolation, while only few studies considered trajectories of drivers through changes to their impacts and their potential feedbacks. We provide a conceptual framework for linking meta-studies of land use change processes and impacts for the analysis of coupled human-environmental systems. Moreover, we provide suggestions for combining meta-studies of different land use change processes to develop a more integrated theory of land use change, and for combining meta-studies of land use change impacts to identify tradeoffs between different impacts. Land use science can benefit from an improved conceptualization of land use change processes and their impacts, and from new methods that combine meta-study findings to advance our understanding of human-environmental systems.

Serotype Diversity of Foot-and-Mouth-Disease Virus in Livestock without History of Vaccination in the Far North Region of Cameroon

Little information is available about the natural cycle of foot-and-mouth disease (FMD) in the absence of control measures such as vaccination. Cameroon presents a unique opportunity for epidemiological studies because FMD vaccination is not practiced. We carried out a prospective study including serological, antigenic and genetic aspects of FMD virus (FMDV) infections among different livestock production systems in the Far North of Cameroon to gain insight into the natural ecology of the virus. We found serological evidence of FMDV infection in over 75% of the animals sampled with no significant differences of prevalence observed among the sampled groups (i.e. market, sedentary, transboundary trade and mobile). We also found antibodies reactive to five of the seven FMDV serotypes (A, O, SAT1, SAT2 and SAT3) among the animals sampled. Finally, we were able to genetically characterize viruses obtained from clinical and subclinical FMD infections in Cameroon. Serotype O viruses grouped into two topotypes (West and East Africa). SAT2 viruses grouped with viruses from Central and Northern Africa, notably within the sublineage causing the large epidemic in Northern Africa in 2012, suggesting a common origin for these viruses. This research will guide future interventions for the control of FMD such as improved diagnostics, guidance for vaccine formulation and epidemiological understanding in support of the progressive control of FMD in Cameroon.

Data-Driven Models of Foot-and-Mouth Disease Dynamics: A Review

Foot-and-mouth disease virus (FMDV) threatens animal health and leads to considerable economic losses worldwide. Progress towards minimizing both veterinary and financial impact of the disease will be made with targeted disease control policies. To move towards targeted control, specific targets and detailed control strategies must be defined. One approach for identifying targets is to use mathematical and simulation models quantified with accurate and fine-scale data to design and evaluate alternative control policies. Nevertheless, published models of FMDV vary in modelling techniques and resolution of data incorporated. In order to determine which models and data sources contain enough detail to represent realistic control policy alternatives, we performed a systematic literature review of all FMDV dynamical models that use host data, disease data or both data types. For the purpose of evaluating modelling methodology, we classified models by control strategy represented, resolution of models and data, and location modelled. We found that modelling methodology has been well developed to the point where multiple methods are available to represent detailed and contact-specific transmission and targeted control. However, detailed host and disease data needed to quantify these models are only available from a few outbreaks. To address existing challenges in data collection, novel data sources should be considered and integrated into models of FMDV transmission and control. We suggest modelling multiple endemic areas to advance local control and global control and better understand FMDV transmission dynamics. With incorporation of additional data, models can assist with both the design of targeted control and identification of transmission drivers across geographic boundaries.

Spatial and Temporal Characteristics of Pastoral Mobility in the Far North Region, Cameroon: Data Analysis and Modeling

Modeling the movements of humans and animals is critical to understanding the transmission of infectious diseases in complex social and ecological systems. In this paper, we focus on the movements of pastoralists in the Far North Region of Cameroon, who follow an annual transhumance by moving between rainy and dry season pastures. Describing, summarizing, and modeling the transhumance movements in the region are important steps for understanding the role these movements may play in the transmission of infectious diseases affecting humans and animals. We collected data on this transhumance system for four years using a combination of surveys and GPS mapping. An analysis on the spatial and temporal characteristics of pastoral mobility suggests four transhumance modes, each with its own properties. Modes M1 and M2 represent the type of transhumance movements where pastoralists settle in a campsite for a relatively long period of time (≥20 days) and then move around the area without specific directions within a seasonal grazing area. Modes M3 and M4 on the other hand are the situations when pastoralists stay in a campsite for a relatively short period of time (<20 days) when moving between seasonal grazing areas. These four modes are used to develop a spatial-temporal mobility (STM) model that can be used to estimate the probability of a mobile pastoralist residing at a location at any time. We compare the STM model with two reference models and the experiments suggest that the STM model can effectively capture and predict the space-time dynamics of pastoral mobility in our study area.

Muddying the waters: a new area of concern for drinking water contamination in Cameroon

In urban Maroua, Cameroon, improved drinking water sources are available to a large majority of the population, yet this water is frequently distributed through informal distribution systems and stored in home containers (canaries), leaving it vulnerable to contamination. We assessed where contamination occurs within the distribution system, determined potential sources of environmental contamination, and investigated potential pathogens. Gastrointestinal health status (785 individuals) was collected via health surveys. Drinking water samples were collected from drinking water sources and canaries. Escherichia coli and total coliform levels were evaluated and molecular detection was performed to measure human-associated faecal marker, HF183; tetracycline-resistance gene, tetQ; Campylobacter spp.; and Staphylococcus aureus. Statistical analyses were performed to evaluate the relationship between microbial contamination and gastrointestinal illness. Canari samples had higher levels of contamination than source samples. HF183 and tetQ were detected in home and source samples. An inverse relationship was found between tetQ and E. coli. Presence of tetQ with lower E. coli levels increased the odds of reported diarrhoeal illness than E. coli levels alone. Further work is warranted to better assess the relationship between antimicrobial-resistant bacteria and other pathogens in micro-ecosystems within canaries and this relationship’s impact on drinking water quality.

What to do with chronically sick animals? Pastoralists' management strategies in the far north region of Cameroon

While the goal of African pastoralists is health and longevity of herd and household, some of their management strategies appear to counter this long-term goal. Pastoralists in the far north region of Cameroon, for example, do not always remove chronically sick animals from their herds, even though chronic diseases, such as brucellosis, are contagious and have the potential to cause fertility problems in the herd. We used ethnographic and epidemiologic methods to understand why pastoralists do not remove chronically sick animals and whether their management strategies have an impact on herd fertility. We used semi-structured interviews to collect data on pastoralists' understandings of disease and its impacts on fertility as well as data on herd management. We compared these data with disease prevalence and herd fertility data to measure the effect of management strategies on herd fertility. We found that the percentage of chronically sick animals in a herd negatively correlated with herd fertility, but this was not true for the prevalence of brucellosis. Thus, preliminary examination of disease costs and benefits suggests that herders' decisions to keep sick animals in their herds may lower herd fertility, but this is not due to brucellosis alone. The results of this study underline the complexity of infectious disease ecology in pastoral systems and the need for holistic and comprehensive studies of the ecology of infectious diseases in pastoral systems.

On Not Knowing Zoonotic Diseases: Pastoralists' Ethnoveterinary Knowledge in the Far North Region of Cameroon

In this article, we consider the implications of Murray Last's (1981)Knowing About Not Knowing for the study of ethnoveterinary knowledge of mobile pastoralists in the Far North Region of Cameroon. Specifically, we ask two interrelated questions: (1) what is the nature of this knowledge, and (2) what is the best way to study it? We conducted a study of pastoralists' knowledge of human and animal infectious diseases to evaluate the claim that mobile pastoralists in the Chad Basin do not have a concept for zoonotic diseases. We used a combination of free lists and semi-structured interviews to study pastoralists' knowledge. The results suggest that pastoralists do not have a concept for zoonotic diseases. Moreover, we found considerable variation in pastoralists' ethnoveterinary knowledge and examples of not knowing, which contrasts with previous studies that do not describe much variation in ethnoveterinary knowledge. In our discussion, we consider to what extent descriptions of ethnoveterinary knowledge are the product of researchers' conceptual framework and methodology.

Kinetic model of hydrogen generation by Rhodobacter sphaeroides in the presence of NH ions

AIMS

To examine the effects of ammonium ion concentration and illumination intensity on the effectivness of the hydrogen generation process of Rhodobacter sphaeroides.

METHODS AND RESULTS

In all experiments the amount of evolved hydrogen, biomass growth, concentration of ammonium ions, pH and chemical oxygen demand were measured. A nonstructural kinetic model was applied in description of biomass growth, the amount of evolved hydrogen and consumption of organic compounds and ammonium ions. An increase of ammonium ions concentration resulted in a decrease of maximal specific hydrogen potential production. At higher ammonium ion concentrations, no hydrogen evolution was observed. The efficiency of malic acid conversion into hydrogen and the PHB content in the biomass were the highest with lower concentrations of nitrogen compounds.

CONCLUSION

The presence of ammonium ions inhibits hydrogen photogeneration. A good agreement between the experimental data and model simulations were obtained. In all cases, hydrogen evolution started after an exhaustion of ammonium ions and the increase was proportional to the C/N ratio in the medium. The accumulation of PHB competes with the hydrogen evolution process while the conversion of acids into biomass was limited at higher levels of hydrogen generation.

SIGNIFICANCE AND IMPACT OF THE STUDY

Confirmation of the suitability of the selected model for kinetic studies of hydrogen photoevolution.

Low discomfort and pain associated with intensified insulin therapy in children and adolescents

OBJECTIVE

Discomfort during insulin injection and self-monitoring of blood glucose (SMBG) is a potential obstacle in diabetes therapy, but its prevalence and extent in relation to clinical variables is uncertain.

RESEARCH DESIGN AND METHODS

We prospectively assessed treatment-associated discomfort and pain in an unselected cohort of patients (60 boys and 52 girls; mean age 14.6+/-3.0 years, mean A1C 8.0+/-1.4%) with type 1 diabetes and multiple daily self-injections of insulin, using visual analogue/verbal rating scales (range, 0-10) and a six-item questionnaire.

RESULTS

Pain during insulin injection was absent to very low in 91.9% of patients, and its intensity was independent of age, gender, diabetes duration, current A1C, injection volume, or type of insulin. Injection was more unpleasant than SMBG in 64.2% of patients (mean difference of pain score, 1.0+/-1.7, p<0.0001). Injection into the upper arm was less painful than into the thigh and abdomen. Surprisingly, painlessness of injection and SMBG was not judged an important treatment goal by 22.0 and 32.9% of patients, respectively. Logistic difficulties (41.2% of responses) and time requirements (23.8%), but not pain (10.1%), were considered most relevant problems.

CONCLUSIONS

In young patients with access to optimized diabetes care, pain during insulin injection and SMBG is infrequent or mild, and not widely perceived as problematic, thus encouraging the use of multiple daily injection treatment.

[Management of accidental hypothermia]

Patients with hypothermia are frequently encountered in emergency medicine. Particularly trauma patients, but also other predisposed persons, can be expected to suffer from hypothermia at any time of the year. Therapy focuses not only on symptom-oriented intensive care to stabilize and secure vital functions, but also on rewarming. Even in cases of severe hypothermia with circulatory arrest, therapy can produce excellent results. This paper first gives a brief overview of the typical clinical symptoms of hypothermia, before giving a detailed description of the preclinical and in-hospital management of the hypothermia patient. The various rewarming strategies are the subject of special attention and critical evaluation.

Aspirin and Clopidogrel Taken Until 2 Days Prior to Coronary Artery Bypass Graft Surgery Is Associated with Increased Postoperative Drainage Loss

OBJECTIVE

Platelet aggregation inhibitors, such as aspirin and clopidogrel, are associated with increased bleeding in patients undergoing cardiac surgery with cardiopulmonary bypass. We investigated the impact of time between the last intake of aspirin and clopidogrel before CABG surgery and drainage loss, transfusion requirements and rate of reoperation.

PATIENTS AND METHODS

The records of patients who had coronary artery bypass graft surgery (CABG) were reviewed for intake of aspirin and clopidogrel within 7 days prior to surgery. Drainage loss, transfusion requirements and rate of reoperation for bleeding within 5 days after the operation, were recorded.

RESULTS

Out of 261 analysed patients, 225 patients (86.2 %) had no anti-platelet medication and 36 patients (13.8 %) were on aspirin and clopidogrel. Aspirin and clopidogrel, taken all until 2 days prior to operation, were associated with a significantly higher postoperative blood loss (1840 mL [1230 - 3710] vs. 280 mL [185 - 765], p = 0.005 for one day and 850 mL [345 - 1725] vs. 277 mL [165 - 778], p = 0.026, for 2 days prior to surgery). The trend showed that patients in the study group received more platelet concentrates (PC: 5.3 % vs. 13.9 %, p = 0.067). The rate of reoperation for bleeding was not different ( p = 0.25).

CONCLUSION

Aspirin and clopidogrel up to 2 days prior to CABG were associated with a significantly higher postoperative drainage loss.

Safety and efficacy of living donor liver preservation with HTK solution

BACKGROUND

In living donor liver transplantation (LDLTx) organ procurement is usually well controlled, and allows to assess liver preservation and graft function under standardized conditions. Because publications on histidine-tryptophan-ketoglutarate (HTK) solution are limited, we prospectively studied its safety and efficacy in a consecutive series of LDLTx.

METHODS

Twenty-four patients received 22 right, 1 left, and 1 left lateral lobe graft. Liver preservation was done by gravity perfusion with HTK through portal vein, and hepatic artery, and flushing of bile ducts. Total ischemia time was 191 +/- 68 minutes.

RESULTS

There was no primary nonfunction, and all partial liver grafts showed good recovery: peak aspartate aminotransferase 577 U/L, total bilirubin 15.15 mg/dL, and partial thromboplastin time 49.37 seconds. One graft was lost from parenchymal fracture secondary to portal hyperperfusion after 6 days, and the patient was salvaged with retransplantation. Thirty-day mortality, including sudden cardiac death, pancreatitis, and hepatic artery rupture, was not related to graft dysfunction. Eight of 24 recipients developed early biliary leakage. There was no late ischemic type biliary lesion.

CONCLUSION

These results confirm that HTK solution is safe and effective when used in LDLTx. Potential advantages of HTK in comparison to other preservation solutions are low potassium concentration, low viscosity, no particles, in situ perfusion, no need to flush before reperfusion, improved biliary protection, better recovery of microcirculatory changes, ready to use, and lower costs. Because the risk-benefit ratio is of particular importance in LDLTx the use of HTK solution should be encouraged.

What Is the Best Immunosuppression in Living Donor Liver Transplantation?

INTRODUCTION

As we have learned, there are no golden rules of immunosuppression in solid organ transplantation, and every transplant program is using its own regimen to prevent or treat rejection. We have retrospectively analyzed the incidence and severity of acute rejection in a consecutive series of living donor liver transplants. The major objective during the whole study period was to ultimately avoid any steroids from the beginning.

METHODS

Twenty one adult patients and five children received 23 right, one left, and two left lateral lobe grafts from genetically or emotionally related living donors, including four ABO-incompatible pairs. The majority of patients had triple initial immunosuppression, based on tacrolimus, mycophenolate mofetil or sirolimus, and basiliximab or daclizumab. Except methylprednisolone administered before reperfusion in 13 patients, only seven had prednisolone after transplantation, and 12/26 had a completely steroid-free regimen.

RESULTS

The overall incidence of biopsy-proven acute rejection was 4/21 in adults (19%) and 4/5 in children (80%). Rejections were mild in five and moderate in three cases, respectively, and easily reversed with steroids in all patients. Different combinations of immunosuppressive drugs or ABO incompatibility did not seem to have an influence on the risk of rejection.

CONCLUSION

Despite the small number of patients in this series, completely steroid-free triple-drug immunosuppression with tacrolimus, mycophenolate mofetil, and basiliximab is safe and efficient to prevent acute rejection in adult recipients of living donor liver transplants. At least short-term administration of prednisolone should be considered in pediatric patients.

Simulect induction facilitates neoral-based steroid-free immunosuppression in primary kidney transplant recipients

This study compares outcomes of kidney transplantation with two distinct induction protocols Basiliximab (Simulect) versus Muromonab (OTK 3) in the setting of cyclosporine (Neoral)-based immunosuppression. Postinduction protocols included either total prednisone avoidance or prednisone sparing versus standard prednisone dosing. Two hundred forty five adult patients receiving kidney transplantation between 1995 and 2000 were included in the study. Treatment in group 1 was OKT 3 + Neoral + adjunct + standard prednisone; group 2, Simulect + Neoral + adjunct + steroid sparing; group 3, Simulect + Neoral + adjunct + no prednisone. The demographics between all groups were similar. The mean (+/- SD) trough cyclosporine levels at 1 month were 276 +/- 128 versus 291 +/- 180 versus 398 +/- 365 (P=.020); at 3 months were 261 +/- 120 versus 280 +/- 152 versus 399 +/- 408 (P=.32); at 12 month were 235 +/- 144 versus 245 +/- 154 versus 234 +/- 132 (P=.96). Creatinine clearance at 1 month was 59 +/- 24 versus 58 +/- 18 versus 47 +/- 23 mL/min (P=.004); at 3 months was 66 +/- 28 versus 62 +/- 22 versus 53 +/- 25 mL/min (P=.007); at 12 months was 68 +/- 38 versus 65 +/- 22 versus 64 +/- 29 mL/min (P=.556). Serum creatinine at 1 month was 1.8 +/- 0.9 versus 1.6 +/- 1.2 versus 2.8 +/- 2.21 mg/dL (P=.005); at 3 months was 1.7 +/- 0.6 versus 1.9 +/- 1.0 versus 2.3 +/- 1.3 mg/dL (P=.007); at 12 months was 1.9 +/- 1.3 versus 2.1 +/- 1.0 versus 2.3 +/- 1.7 mg/dL (P=.179). The incidence of acute rejection within 1 year in the respective groups were 28% versus 15% versus 16%. Therefore, we conclude that using Simulect in transplant recipients results in long-term patient and graft survival similar to those achieved with OKT 3. The use of Simulect resulted in significant reduction in clinical rejection incidence within the first year regardless of steroid use. Thus, the use of Simulect allows complete steroid avoidance in Neoral-based immunosuppression regimen.

Watching social interactions produces dorsomedial prefrontal and medial parietal BOLD fMRI signal increases compared to a resting baseline

Some human brain areas are tonically active in a resting state when subjects are not engaged in any overt task. The activity of these areas decreases when subjects are engaged in a wide variety of laboratory tasks designed to study cognitive operations. It has been suggested that these areas, among them the medial parietal (precyneus) and the dorsomedial prefrontal cortices, may support a "default state" of the human brain. Passive visual observation of laboratory stimuli typically yields no change in activity in these default areas compared to rest. Here we report functional magnetic resonance imaging (fMRI) data on normal subjects watching realistic movie clips depicting everyday social interactions. In contrast with previous findings on default state brain areas, the observation of the relational segment of the movie clip, during which two persons interact, yielded increased activity in the medial parietal (precuneus) and dorsomedial prefrontal cortices, compared to rest and to observation of the segment of the movie clip depicting a single individual engaged in everyday activities. To the best of our knowledge, this is the first report of joint increased activity in medial parietal and dorsomedial prefrontal cortices. We suggest that the default state areas may participate in the processing of social relations in concert with regions previously identified as critical for social cognition that were also activated by our stimuli, including the inferior frontal cortex, the superior temporal cortex, and the fusiform gyrus.

GCP5 and GCP6: two new members of the human gamma-tubulin complex

The gamma-tubulin complex is a large multiprotein complex that is required for microtubule nucleation at the centrosome. Here we report the purification and characterization of the human gamma-tubulin complex and the identification of its subunits. The human gamma-tubulin complex is a ring of ~25 nm, has a subunit structure similar to that reported for gamma-tubulin complexes from other species, and is able to nucleate microtubule polymerization in vitro. Mass spectrometry analysis of the human gamma-tubulin complex components confirmed the presence of four previously identified components (gamma-tubulin and gamma-tubulin complex proteins [GCPs] 2, 3, and 4) and led to the identification of two new components, GCP5 and GCP6. Sequence analysis revealed that the GCPs share five regions of sequence similarity and define a novel protein superfamily that is conserved in metazoans. GCP5 and GCP6, like other components of the gamma-tubulin complex, localize to the centrosome and associate with microtubules, suggesting that the entire gamma-tubulin complex takes part in both of these interactions. Stoichiometry experiments revealed that there is a single copy of GCP5 and multiple copies of gamma-tubulin, GCP2, GCP3, and GCP4 within the gamma-tubulin complex. Thus, the gamma-tubulin complex is conserved in structure and function, suggesting that the mechanism of microtubule nucleation is conserved.

Impact of residual renal function in children on hemodialysis

Residual renal function (RRF) contributes to dialysis adequacy as well as lower mortality and morbidity in dialysis patients. Even very small changes in glomerular filtration rate (GFR) account for considerable improvements in complications of dialysis. The purpose of this cross-sectional study is to determine the possible contribution of RRF to hemodialysis clearance and to compare the biochemical markers of this patient group with anuric patients. Ten patients with RRF on chronic hemodialysis for more than 6 months were enrolled in the study. Duration of dialysis was not different between the two patient populations. Average GFR was 3.4+/-2.6 ml/min in the group with RRF. Cholesterol, albumin, and triglyceride levels were not different between the groups. Residual renal urea clearance enhanced mean Kt/V of patients from 1.29 to 1.52. However erythropoietin and renin levels were higher in the group with RRF (P=0.019, P=0.044, respectively). There was a positive correlation between erythropoietin, renin levels, and average GFR of all patients (r=0.69, P=0.002, r=0.60, P=0.014). We conclude that RRF plays a greater role in pediatric patients on hemodialysis than previously recognized, and knowledge about patients' RRF should assist in improved overall management.

Gamma-tubulin complexes and microtubule nucleation

Microtubules are dynamic cytoskeletal polymers that assemble from alpha/beta-tubulin and are vital for the establishment of cell polarity, vesicle trafficking and formation of the mitotic/meiotic spindle. gamma-Tubulin, a protein related to alpha/beta-tubulin, is required for initiating the polymerization of microtubules in vivo. gamma-Tubulin has been found in two main protein complexes: the gamma-tubulin ring complex and its subunit, the gamma-tubulin small complex. The latter is analogous to the yeast Tub4 complex. In the past year, important advances have been made in understanding the structure and function of the gamma-tubulin ring complex and how it interacts with microtubules.

Activating mineralocorticoid receptor mutation in hypertension exacerbated by pregnancy

Hypertension and pregnancy-related hypertension are major public health problems of largely unknown causes. We describe a mutation in the mineralocorticoid receptor (MR), S810L, that causes early-onset hypertension that is markedly exacerbated in pregnancy. This mutation results in constitutive MR activity and alters receptor specificity, with progesterone and other steroids lacking 21-hydroxyl groups, normally MR antagonists, becoming potent agonists. Structural and biochemical studies indicate that the mutation results in the gain of a van der Waals interaction between helix 5 and helix 3 that substitutes for interaction of the steroid 21-hydroxyl group with helix 3 in the wild-type receptor. This helix 5-helix 3 interaction is highly conserved among diverse nuclear hormone receptors, suggesting its general role in receptor activation.

Structure of the gamma-tubulin ring complex: a template for microtubule nucleation

The gamma-tubulin ring complex (gammaTuRC) is a protein complex of relative molecular mass approximately 2.2 x 10(6) that nucleates microtubules at the centrosome. Here we use electron-microscopic tomography and metal shadowing to examine the structure of isolated Drosophila gammaTuRCs and the ends of microtubules nucleated by gammaTuRCs and by centrosomes. We show that the gammaTuRC is a lockwasher-like structure made up of repeating subunits, topped asymmetrically with a cap. A similar capped ring is also visible at one end of microtubules grown from isolated gammaTuRCs and from centrosomes. Antibodies against gamma-tubulin label microtubule ends, but not walls, in centrosomes. These data are consistent with a template-mediated mechanism for microtubule nucleation by the gammaTuRC.

Pregnancy in lung transplant recipients

Eight female lung transplant recipients, all of whom became pregnant after transplant, were reported to the National Transplantation Pregnancy Registry from US transplant centers. Outcomes of the 8 pregnancies were 4 live births, 3 therapeutic abortions, and 1 spontaneous abortion. Three of the 4 newborns were premature, with low birth weight (< 2500 grams). Rejection during pregnancy occurred in 3 pregnancies (38%). All 8 transplant recipients reported at least 1 complication during pregnancy, including shortness of breath, rejection, and infection. Two of the 4 deliveries were by cesarean section. At follow-up, all children were developing well with no residual problems. Female lung transplant recipients may face higher risks during pregnancy than other solid organ transplant recipients.

Erythropoietin response to post-liver transplantation anemia

Anemia frequently accompanies end-stage liver disease. Erythropoietin has recently been shown to be of benefit in a number of diseases complicated by anemia. We studied erythropoietin levels before and after orthotopic liver transplantation (OLT) and correlated these with the degree of anemia. Twenty-seven patients with end-stage cirrhosis who underwent OLT had preoperative and weekly postoperative serum erythropoietin levels determined by a highly sensitive radioimmunoassay. The relation of erythropoietin level to the values for hematocrit, serum creatinine, and cyclosporine and other biochemical test results was evaluated. Before transplantation, 23 patients were anemic; erythropoietin levels were appropriately elevated (72.7 +/- 37 mU/mL; normal, 10 to 15 mU/mL) for the degree of anemia (hematocrit, 33.1% +/- 1%) in 16 patients (70%). A blunted erythropoietin response to anemia was found in 7 of the anemic patients with cirrhosis (30%). After OLT, the hematocrit decreased to 29.5% +/- 0.6% at 4 weeks, with a reciprocal increase in serum erythropoietin levels to 36 +/- 5 mU/mL. Erythropoietin response appeared appropriate to the degree of anemia in 82% of the liver transplant recipients and blunted in 18%. We conclude that the ability to secrete erythropoietin in response to anemia is defective in many patients with end-stage liver disease, and a normal response may be restored after OLT. The results suggest that exogenous erythropoietin administration may be beneficial in anemic patients with cirrhosis and liver transplant recipients who have inappropriately low serum erythropoietin levels.

Recruitment of the gamma-tubulin ring complex to Drosophila salt-stripped centrosome scaffolds

Extracting isolated Drosophila centrosomes with 2 M KI generates salt-resistant scaffolds that lack the centrosomal proteins CP190, CP60, centrosomin, and gamma-tubulin. To clarify the role of these proteins in microtubule nucleation by centrosomes and to identify additional centrosome components required for nucleation, we have developed an in vitro complementation assay for centrosome function. Centrosome aster formation is reconstituted when these inactive, salt-stripped centrosome scaffolds are supplemented with a soluble fraction of a Drosophila embryo extract. The CP60 and CP190 can be removed from this extract without effect, whereas removing the gamma-tubulin destroys the complementing activity. Consistent with these results, we find no evidence that these three proteins form a complex together. Instead, gamma-tubulin is found in two distinct protein complexes of 240,000 and approximately 3,000,000 D. The larger complex, which is analogous to the Xenopus gamma-tubulin ring complex (gammaTuRC) (Zheng, Y., M.L. Wong, B. Alberts, and T. Mitchison. 1995. Nature. 378:578-583), is necessary but not sufficient for complementation. An additional factor found in the extract is required. These results provide the first evidence that the gammaTuRC is required for microtubule nucleation at the centrosome.