ABSTRACT
Adaptive radiation occurs when species diversify rapidly to occupy an array of ecological niches. As opportunities for parasite infection and transmission may greatly vary among these niches, adaptive radiation is expected to be associated with a turnover of the parasite community. As major agents of natural and sexual selection, parasites may play a central role in host diversification. The study of parasite turnover may thus be of general relevance and could significantly improve our understanding of adaptive radiation. In this study, we examined the parasite faunas of eleven species belonging to the tribe Tropheini, one of several adaptive radiations of cichlid fishes in Lake Tanganyika. The most parsimonious ancestral foraging strategy among the Tropheini is relatively unselective substrate browsing of aufwuchs. Several lineages evolved more specialized foraging strategies, such as selective combing of microscopic diatoms or picking of macro-invertebrates. We found that representatives of these specialized lineages bear reduced infection with food-web-transmitted acanthocephalan helminths, but not with parasites with a direct life cycle. Possibly, the evolution of selective foraging strategies entailed reduced ingestion of intermediate invertebrate hosts of acanthocephalans. We conclude that some species belonging to the Tropheini virtually escape acanthocephalan infection as a by-product of trophic specialization.
Subject(s)
Biological Evolution , Cichlids/parasitology , Helminths/pathogenicity , Phylogeny , Animals , Food Chain , Parasites , TanzaniaABSTRACT
BACKGROUND AND PURPOSE: Methcathinone abuse is a new cause of manganism. The psychostimulant is prepared from pseudoephedrine using potassium permanganate as an oxidant. We describe the clinical, biological, neuroimaging characteristics and follow-up results in a large Estonian cohort of intravenous methcathinone users. METHODS: During 2006-2012 we studied 38 methcathinone abusers with a mean age of 33â years. Subjects were rated by the Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn and Yahr (HY), and Schwab and England (SE) rating scales. Twenty-four cases were reassessed 9-70 (20â ±â 15)â months after the initial evaluation. Manganese (Mn) in plasma and hair was analysed by inductively coupled plasma-atom emission spectrometry. Magnetic resonance imaging (MRI) was performed in 11, and single-photon emission computed tomography (SPECT) with iodobenzamide (IBZM) in eight subjects. RESULTS: The average total UPDRS score was 43â ±â 21. The most severely affected domains in UPDRS Part III were speech and postural stability, the least affected domain was resting tremor. At follow-up there was worsening of HY and SE rating scales. Subjects had a higher mean level of Mn in hair (2.9â ±â 3.8â ppm) than controls (0.82â ±â 1.02â ppm), Pâ =â 0.02. Plasma Mn concentrations were higher (11.5â ±â 6.2â ppb) in active than in former users (5.6â ±â 1.8â ppb), Pâ =â 0.006. Active methcathinone users had increased MRI T1-signal intensity in the globus pallidus, substantia nigra and periaquaductal gray matter. IBZM-SPECT showed normal symmetric tracer uptake in striatum. CONCLUSION: Methcathinone abusers develop a distinctive hypokinetic syndrome. Though the biomarkers of Mn exposure are characteristic only of recent abuse, the syndrome is not reversible.
Subject(s)
Manganese/blood , Parkinson Disease, Secondary/blood , Parkinson Disease, Secondary/chemically induced , Propiophenones , Substance-Related Disorders/blood , Adolescent , Adult , Biomarkers/blood , Biomarkers/chemistry , Cohort Studies , Estonia/epidemiology , Female , Follow-Up Studies , Hair/chemistry , Humans , Male , Middle Aged , Parkinson Disease, Secondary/epidemiology , Propiophenones/adverse effects , Substance-Related Disorders/epidemiology , Young AdultABSTRACT
The aim of this paper is to examine the patterns of polychlorinated biphenyls (PCB) in the grey seals (Halichoerus grypus) from the Baltic, Northeast and Eastern England, and the St. Lawrence Estuary (Canada). In fact, the feeding habits of the ringed seal (Phoca hispida) include ingestion of major quantities of benthic crustaceans that might cause observed differences obtained in PCBs, whereas the grey seal feed mainly on fish. The profile (percent in mixture) of polychlorinated biphenyls (PCB) 101, 118, 138, 153, and 180, and the total of their concentrations in mg/kg lipid in grey seals from the Baltic, from Northeast and Eastern England, and from the St. Lawrence estuary (Canada), were examined by principal component analysis (PCA). When considering the possible effects of consuming seafood by the grey seal, it is necessary to characterize populations and individuals according to the amounts they consume, since populations in different parts of the world are likely to show big differences in their consumption of seafood. The patterns differ between juveniles and adult animals, but the gender of adults and geography do not appear to play a role.
Subject(s)
Adipose Tissue/chemistry , Polychlorinated Biphenyls/analysis , Seals, Earless/metabolism , Water Pollutants, Chemical/analysis , Animals , Environmental Monitoring , Female , Male , Oceans and Seas , Polychlorinated Biphenyls/metabolism , Principal Component Analysis , Water Pollutants, Chemical/metabolismABSTRACT
OBJECTIVE: To compare three methods for rating legitimate use of psychiatric emergency services (PES) in order to develop criteria that can differentiate appropriate from inappropriate PES service requests. METHOD: Ratings of PES visits by treating physicians and ratings of the same visits made during review of medical records. STUDY DESIGN: Two previously used methods of identifying justified PES service use were compared with the treating physician's rating of the same: (1) hospitalization as visit outcome and (2) retrospective chart ratings of visit characteristics using traditional medico-surgical criteria for "emergent" illness episodes. DATA EXTRACTION METHODS: Data were extracted through use of a physician questionnaire, and medical and administrative record review. PRINCIPAL FINDINGS: Agreement between the methods ranged from 47.1 percent to 74.1 percent. A total of 21.7 percent of visits were rated as true health "emergencies" by the traditional definition, while 70.4 percent of visits were rated as "necessary" by treating physicians, and 21.0 percent resulted in hospitalization. Acuteness of behavioral dyscontrol and imminent dangerousness at the time of the visit were common characteristics of appropriate use by most combinations of the three methods of rating visits. CONCLUSIONS: The rating systems employed in similar recent studies produce widely varying percentages of visits so classified. However, it does appear likely that a minimum of 25-30 percent of visits are nonemergent and could be triaged to other, less costly treatment providers. Proposed criteria by which to identify "legitimate" psychiatric emergency room treatment requests includes only patient presentations with (a) acute behavioral dyscontrol or (b) imminent dangerousness to self or others.
Subject(s)
Emergency Service, Hospital/statistics & numerical data , Emergency Services, Psychiatric/statistics & numerical data , Mental Disorders/classification , Needs Assessment , Utilization Review , Adolescent , Adult , Female , Health Services Research , Hospitals, Municipal/statistics & numerical data , Humans , Logistic Models , Male , Medical Audit , Texas/epidemiologyABSTRACT
Utilization rates for urban psychiatric emergency services remain high, and the decision to seek care in this setting is poorly understood. Three hundred individuals accompanying patients to a psychiatric emergency service were interviewed about their help seeking and choice of treatment setting. Twenty-three of the interviewees (7.7 percent) were caregivers accompanying patients with severe and persistent mental illness. They were significantly more likely than other interviewees to know the difference between psychiatric emergency services and services offered by other outpatient providers. More than half reported that the patient they accompanied was intermittently noncompliant, which required visiting either a walk-in service during a moment when the patient was cooperative or a facility equipped to provide involuntary treatment.
Subject(s)
Caregivers/statistics & numerical data , Decision Making , Emergency Services, Psychiatric/statistics & numerical data , Health Behavior , Mental Disorders , Adolescent , Adult , Female , Humans , Male , Middle Aged , United StatesABSTRACT
OBJECTIVE: To describe the results of a structured kidney-transplantation programme available to dialysis patients in Curaçao (Dutch Caribbean), involving transplantation in the Netherlands and follow-up in Curaçao. DESIGN: Descriptive. METHOD: In 1998, a joint venture was begun with the Academic Medical Center (AMC) in Amsterdam, the Eurotransplant Foundation, the Dutch Transplantation Working Party and the Diagnostic Division of the Sanquin Foundation in Amsterdam, the Netherlands. Its aim was to achieve a structural kidney transplantation programme for patients in the Dutch Caribbean in general and patients in Curaçao in particular. An airlift programme between Curaçao and the AMC was instituted. RESULTS: Between 1998-2001 19 patients underwent a kidney transplant, three of which failed. In most of the transplants the cold ischaemia time was less than 48 hours; the average cold ischaemia time was 32 hours. All patients returned to the Antilles within 3 months where their treatment was continued. Post-transplantation follow-up was on average 13.9 months (limits 3-36); three patients died.
Subject(s)
Kidney Transplantation , Patient Transfer , Adult , Aged , Air Ambulances , Female , Graft Rejection , Humans , Male , Middle Aged , Netherlands , Netherlands Antilles , Reperfusion Injury , Treatment OutcomeABSTRACT
Fluorescent antischistosomiasis antibodies appear earlier in mice infected by 150/200 cercariae than in those who only received 20. The use of a homologous antigen in mice infected by S. mansoni or S. haematobium allows earlier and more important responses. The infections by S. haematobium seem to determinate in mice a more important immune responsiveness. Is it a specific parasitic manifestation (S. mansoni being better adapted to rodents?).
Subject(s)
Antibody Formation , Schistosomiasis/immunology , Animals , Fluorescent Antibody Technique , Mice , Schistosoma haematobium/immunology , Schistosoma mansoni/immunology , Species Specificity , Time FactorsABSTRACT
The study of anti Schistosoma mansoni and anti Schistosoma haematobium sera by homologous and heterologous antigen shows that Schistosoma haematobium has an immunogenic strength as good as that of Schistosoma mansoni. The joint use of the two antigens can be useful in epidemiologic investigations in Africa so as to track down seats of Schistosoma mansoni and Schistosoma haematobium and the prevalence of the infection.
Subject(s)
Antibodies/analysis , Schistosoma haematobium/immunology , Schistosoma mansoni/immunology , Schistosomiasis/immunology , Animals , Antigens , Fluorescent Antibody Technique , Humans , Species SpecificityABSTRACT
A comparative study of the value of antigenic sections of S. mansoni and S. haematobium in indirect immunofluorescence applied to the diagnosis of S. intercalatum rectal bilharziosis (in 66 cases) shows that far better results are obtained with S. haematobium antigen (83,3 0/0 positive reactions with higher titers dilution) than with S. mansoni (33,3 0/0 positive reactions).
Subject(s)
Fluorescent Antibody Technique , Rectal Diseases/diagnosis , Schistosomiasis/diagnosis , Adolescent , Adult , Africa , Antigens/immunology , Humans , Middle Aged , Schistosoma haematobium/immunology , Schistosoma mansoni/immunologyABSTRACT
The Schleider and/or the Exner test have been found positive in twenty-one patients; five of these patients suffered of systemic lupus erythematosus (SLE). The Quick time and the activated partial thromboplastin time are normal in 52% of the cases. 40% have a minor haemorrhagic diathesis, without other significant clotting defect and 30% have thrombo-embolic complications. The Schleider index is more often strongly positive (greater than 2) in these two groups. 58% have an anemia, 25% a mild thrombocytopenia not deep enough to explain an haemorrhagic tendency (from 90.000 to 140.000/mm3). Several auto-immune tests are frequently positive even without SLE. The Schleider test is positive in 86% of the cases and appears a little more useful for the diagnosis than the Exner test, which has a 71% positivity.