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1.
PLoS One ; 9(1): e83873, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24416177

RESUMO

Over the last years there has been a massive increase in rhinoceros poaching incidents, with more than two individuals killed per day in South Africa in the first months of 2013. Immediate actions are needed to preserve current populations and the agents involved in their protection are demanding new technologies to increase their efficiency in the field. We assessed the use of remotely piloted aircraft systems (RPAS) to monitor for poaching activities. We performed 20 flights with 3 types of cameras: visual photo, HD video and thermal video, to test the ability of the systems to detect (a) rhinoceros, (b) people acting as poachers and (c) to do fence surveillance. The study area consisted of several large game farms in KwaZulu-Natal province, South Africa. The targets were better detected at the lowest altitudes, but to operate the plane safely and in a discreet way, altitudes between 100 and 180 m were the most convenient. Open areas facilitated target detection, while forest habitats complicated it. Detectability using visual cameras was higher at morning and midday, but the thermal camera provided the best images in the morning and at night. Considering not only the technical capabilities of the systems but also the poachers modus operandi and the current control methods, we propose RPAS usage as a tool for surveillance of sensitive areas, for supporting field anti-poaching operations, as a deterrent tool for poachers and as a complementary method for rhinoceros ecology research. Here, we demonstrate that low cost RPAS can be useful for rhinoceros stakeholders for field control procedures. There are, however, important practical limitations that should be considered for their successful and realistic integration in the anti-poaching battle.


Assuntos
Aeronaves , Conservação dos Recursos Naturais/métodos , Perissodáctilos/fisiologia , Tecnologia de Sensoriamento Remoto/instrumentação , Tecnologia de Sensoriamento Remoto/métodos , Aeronaves/economia , Animais , Conservação dos Recursos Naturais/economia , Fotografação , África do Sul , Gravação em Vídeo
2.
Arch Dis Child ; 93(3): 236-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17925327

RESUMO

A cross-sectional study showed that 130 out of 1758 (8%) primary school children without a previous asthma diagnosis had undiagnosed asthma. Thirty-eight per cent of their parents refused to visit a general practitioner for this disorder. Factors associated with the refusal were high maternal education, mild symptoms and absence of airway reversibility.


Assuntos
Asma/diagnóstico , Pais/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Atitude Frente a Saúde , Criança , Estudos Transversais , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Países Baixos
3.
Eur J Neurosci ; 20(12): 3233-43, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15610156

RESUMO

Removal of circulating corticosterone by adrenalectomy (ADX) leads to apoptosis after 3 days in a small population of rat dentate granule neurons, whereas most surrounding cells remain viable. Interestingly, a specific expression profile is triggered in surviving granule cells that may enhance their survival. Hippocampal slices prepared 1, 2 or 3 days after ADX or sham operation were stained ex vivo with Hoechst 33258, which serves to identify apoptotic neurons. After electrophysiological analysis, multiple gene expression in surviving individual granule cells was assessed by linear antisense RNA amplification and hybridization to slot blots containing various neuronal cDNAs. Hierarchical clustering and principal component analysis was performed on two physiological variables and 14 mRNA ratios from ADX cells from every time point. Our results indicate that surviving 3-day ADX granule cells display lower membrane capacitance, lower relative N-methyl-d-aspartate (NMDA) R1 mRNA expression and higher relative mineralocorticoid receptor (MR), alpha1A voltage-gated Ca-channel, Bcl-2 and NMDA R2C mRNA expression. Some 1- and 2-day ADX cells cluster with these 3-day survivors; therefore, one or more components of their mRNA expression profile may represent predictive markers for apoptosis resistance. The functional relevance of two candidate genes was tested by in vivo local over-expression in the same model system; of these, Bcl-2 conferred partial protection when induced shortly before ADX. Therefore, removal of corticosteroids triggers a specific gene expression profile in surviving dentate granule cells; key components of this profile may be associated with their survival.


Assuntos
Sobrevivência Celular/fisiologia , Corticosterona/deficiência , Giro Denteado/metabolismo , Perfilação da Expressão Gênica/estatística & dados numéricos , Adrenalectomia/estatística & dados numéricos , Animais , Corticosterona/biossíntese , Corticosterona/genética , Giro Denteado/citologia , Perfilação da Expressão Gênica/métodos , Técnicas In Vitro , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos
4.
Med Teach ; 26(4): 301-4, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15203841

RESUMO

The assessment of the elective clerkship at the University of Groningen consists of a written case report, graded by one of four independent reviewers, and a rating of clinical performance by the students' supervisors. This study analyses the grades of 710 case reports and 189 ratings. The grades were found to be normally distributed, similar for the reviewers and consistent over the years, but inter- or intra-observer variation was not studied. The ratings of clinical performance were skewed towards 'excellent'. There was a low correlation between the two assessments (Spearman's r = 0.25; p = 0.001). This may be attributed among other things to the large number of supervisors and the face-to-face assessment of clinical performance versus the distant assessment of a written document. A more relevant explanation, however, is that the case reports measure primarily cognitive aspects, as compared with overall clinical performance.


Assuntos
Estágio Clínico , Competência Clínica , Avaliação Educacional/métodos , Estudantes de Medicina , Países Baixos
5.
Ned Tijdschr Geneeskd ; 146(25): 1161-5, 2002 Jun 22.
Artigo em Holandês | MEDLINE | ID: mdl-12109304

RESUMO

Three patients, men aged 21, 57 and 53 years, presented with variable non-specific symptoms such as general malaise, weight loss, elevated temperature, abdominal pain, cough, pulmonary crepitations and elevated liver enzymes. Diffuse fine nodular infiltration was seen on chest radiography in the last two cases. The first patient refused to be tentatively treated with tuberculostatics and died. Mycobacterium tuberculosis complex grew on Löwenstein medium a week later. The two other patients received tuberculostatic treatment. The second patient recovered, while the third patient suffered a cerebrovascular accident on top of emaciation and respiratory insufficiency and died. In the Netherlands, currently more than one hundred patients with tuberculosis disease die each year. The disease is mostly seen in people from the high-risk groups for tuberculosis such as asylum seekers and immigrants. Even after extensive diagnostic procedures it can be difficult to obtain rapid bacteriological confirmation. When miliary tuberculosis is suspected it is important to carry out the complete range of tests (Ziehl Neelsen microscopy, PCR, Löwenstein cultivation) and to start therapy immediately and not to await the results of the diagnostic tests. However, in many cases this may still be too late, with an estimated mortality of 20%.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Miliar/diagnóstico , Adulto , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/crescimento & desenvolvimento , Países Baixos/epidemiologia , Radiografia Torácica , Fatores de Risco , Recusa do Paciente ao Tratamento , Tuberculose Miliar/tratamento farmacológico , Tuberculose Miliar/mortalidade
6.
Neth J Med ; 57(4): 169-71, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11006494

RESUMO

Epstein-Barr viral (EBV)-infection usually presents as fever, sore throat, fatigue, lymphadenopathy and atypical lymphocytosis. We describe a patient with disseminated intravascular coagulation as the presenting symptom caused by a primary EBV infection.


Assuntos
Coagulação Intravascular Disseminada/virologia , Mononucleose Infecciosa/complicações , Mononucleose Infecciosa/diagnóstico , Adulto , Diagnóstico Diferencial , Coagulação Intravascular Disseminada/sangue , Epistaxe/virologia , Feminino , Febre/virologia , Humanos , Hemorragia Uterina/virologia
7.
Proc Natl Acad Sci U S A ; 96(23): 13456-61, 1999 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-10557342

RESUMO

Recent studies indicated that hyperactivity of the hypothalamo-pituitary-adrenal system is a considerable risk factor for the precipitation of affective disorders, most notably of major depression. The mechanism by which this hyperactivity eventually leads to clinical symptoms of depression is unknown. In the present animal study, we tested one possible mechanism, i.e., that long-term exposure to high corticosterone levels alters functional responses to serotonin in the hippocampus, an important area in the etiology of depression. Rats were injected daily for 3 weeks with a high dose of corticosterone; electrophysiological responses to serotonin were recorded intracellularly from CA1 pyramidal neurons in vitro. We observed that daily injections with corticosterone gradually attenuate the membrane hyperpolarization and resistance decrease mediated by serotonin-1A receptors. We next used single-cell antisense RNA amplification from identified CA1 pyramidal neurons to resolve whether the functional deficits in serotonin responsiveness are accompanied by decreased expression levels of the serotonin-1A receptor. It appeared that expression of serotonin-1A receptors in CA1 pyramidal cells is not altered; this result was supported by in situ hybridization. Expression of corticosteroid receptors in the same cells, particularly of the high-affinity mineralocorticoid receptor, was significantly reduced after long-term corticosterone treatment. The present findings indicate that prolonged elevation of the corticosteroid concentration, a possible causal factor for major depression in humans, gradually attenuates responsiveness to serotonin without necessarily decreasing serotonin-1A receptor mRNA levels in pyramidal neurons. These functional changes may occur by a posttranscriptional mechanism or by transcriptional regulation of genes other than the serotonin-1A receptor gene itself.


Assuntos
Corticosterona/farmacologia , Hipocampo/efeitos dos fármacos , Serotonina/metabolismo , Animais , Corticosterona/administração & dosagem , Hipocampo/metabolismo , Hibridização In Situ , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética
8.
J Intern Med ; 237(3): 293-9, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7891050

RESUMO

OBJECTIVES: A description of the clinical presentation, diagnostic procedure and mode of therapy in three patients suffering from chronic mesenteric ischaemia. DESIGN AND INTERVENTIONS: In all cases, the diagnosis was made on the basis of abdominal complaints in combination with angiographic findings. The primary treatment objective was restoration of blood flow via a revascularization procedure, for the patient in whom this could not be accomplished an enteral feeding programme was undertaken. RESULTS: One patient had a panmalabsorption syndrome which was treated with an aortomesenteric bypass operation, the second one presented with multiple gastric ulcerations which only improved after a percutaneous transluminal angioplasty. In the third patient, neither surgery or angioplasty were feasible and a tentative enteral feeding programme was given, after which the ability to consume a normal oral diet without abdominal distress was regained. CONCLUSIONS: These three cases illustrate the diverse clinical pictures by which chronic mesenteric ischaemia may present itself. This diagnosis should be kept in mind when other more common causes of a patient's abdominal complaints cannot be found, hence giving consideration to abdominal angiography as the next diagnostic procedure. With respect to therapy, restoring blood flow through surgery or angioplasty is the primary form of treatment. However, if neither of these therapeutic options is feasible, it is suggested that such patients may benefit from a nutritional training programme.


Assuntos
Isquemia/diagnóstico , Isquemia/terapia , Mesentério/irrigação sanguínea , Angiografia , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Mesentério/diagnóstico por imagem , Pessoa de Meia-Idade
9.
Neth J Med ; 45(3): 110-3, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7969663

RESUMO

A patient with familial benign hypercalcaemia (FBH) who developed relapsing pancreatitis is presented. She underwent distal partial pancreas resection with surgical removal of pancreatic duct stones, and a pancreaticojejunostomy. No further causes for the pancreatitis were found. The present case is remarkable since it is an example of the occurrence of pancreatitis in a previously known patient with hypercalcaemia, and it underlines the severity of the pancreatitis when it occurs in this syndrome.


Assuntos
Hipercalcemia/complicações , Pancreatite/etiologia , Doença Aguda , Adolescente , Família , Feminino , Humanos
11.
Cancer ; 67(11): 2826-7, 1991 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1827357

RESUMO

A 38-year-old man with idiopathic hypereosinophilic syndrome had an inadequate response to steroids and severe side effects from hydroxyurea treatment, which necessitated withdrawal of the treatment. Successful control of clinical symptoms and eosinophil counts was obtained with etoposide (VP16-213) for 18 months. VP16-213 may be valuable in idiopathic hypereosinophilic syndrome treatment.


Assuntos
Eosinofilia/tratamento farmacológico , Etoposídeo/uso terapêutico , Adulto , Cardiomegalia/complicações , Humanos , Hidroxiureia/efeitos adversos , Masculino , Síndrome , Trombocitopenia/induzido quimicamente
12.
Prev Med ; 19(6): 642-55, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2263575

RESUMO

Cardiovascular disease is recognized as a serious public health problem. Because the underlying pathological processes start shortly after birth, tracking of recognized cardiovascular disease indicators during childhood and adolescence can help in developing preventive pediatric strategies. A prospective follow-up of both genetic and behavioral lifestyle parameters (serum cholesterol, blood pressure, percentage body fat, maximal oxygen uptake (VO2max), smoking, physical inactivity, and type A behavior) was designed. In the Amsterdam Growth and Health Study a population of 93 males and 107 females was measured annually from 1977 to 1980 and a fifth measurement was made in 1985. In that way longitudinal data covering a period of 8 years was collected for a group of adolescents/adults between 13 and 21 years of age. Analyses of these parameters provided the following results: The stability over the 9 years of tracking cardiovascular disease indicators, measured as the interperiod correlations, is fairly high. It varies from 0.4 to 0.8 in percentage body fat, cholesterol, and VO2max. Blood pressure values are low (between 0.3 and 0.4). The probability of 13-year-olds having relatively high values of cardiovascular disease indicators on the basis of a quartile distribution with that at age 21 indicated a moderate to high predictive value. According to the literature, the levels of subjects that are continuously relatively high over the years are more in the direction of optimal health than risk values. The exception is for percentage body fat. Interrelation of the seven cardiovascular disease indicators in constantly relatively high-risk and relatively low-risk groups during the teenage period, measured during young adulthood (21.5 years), appeared to be weak: only males and females with a high percentage body fat and a low VO2max showed significantly high total cholesterol, low high-density lipoprotein cholesterol, and high total cholesterol/high-density lipoprotein cholesterol levels. From the three environmental cardiovascular disease indicators (smoking, physical activity, and type A/B behavior) measured in 1985, only physical activity was significantly correlated among males and females with high-density lipoprotein cholesterol, percentage body fat, and VO2max. It can be concluded that measurement of percentage body fat in the early teenage period seems to be the most important cardiovascular disease indicator in predicting risk levels in the young adult. The amount of physical activity measured at young adult age is the only behavioral parameter to show a significant interrelation with other cardiovascular disease risk indicators.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Composição Corporal , Doenças Cardiovasculares/epidemiologia , Indicadores Básicos de Saúde , Inquéritos Epidemiológicos , Adolescente , Adulto , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/fisiopatologia , Colesterol/sangue , Feminino , Seguimentos , Humanos , Estilo de Vida , Estudos Longitudinais , Medidas de Volume Pulmonar , Masculino , Países Baixos/epidemiologia , Fatores de Risco , Personalidade Tipo A
13.
Eur J Clin Pharmacol ; 38(4): 335-41, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2344857

RESUMO

Using available data on time-concentration and time-effect relationships in normal persons the results of infusion of digoxin in various time periods were simulated and compared with administration of digoxin by bolus injections, using a three-compartment pharmacokinetic model to which a separate small side-effect compartment was subsequently added. The validity of the simulations was tested in 11 patients with rapid atrial fibrillation. Serum digoxin concentrations, ventricular rate and side effects were monitored in a double-blind study comparing an infusion of 1.5 mg digoxin over 6 h with administration of three bolus injections of 0.5 mg digoxin 8 h apart. In agreement with the predictions of the model, the maximal fall in ventricular rate was reached after 8-9 h in the infusion group and after 19-20 h in the bolus injection group, without any detectable difference in side effects. There were certain discrepancies between the results of the clinical study and the predictions of the model, e.g. in serum digoxin concentrations, perhaps due to impaired clearance in the patients. However, it is concluded that the tested model is valid in elderly patients with rapid atrial fibrillation.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Digoxina/administração & dosagem , Adulto , Idoso , Fibrilação Atrial/sangue , Digoxina/farmacocinética , Digoxina/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Modelos Biológicos
14.
Br J Nutr ; 57(2): 161-76, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3567131

RESUMO

Longitudinal changes in nutritional habits were studied in Dutch adolescents from 12 to 17 years of age (131 girls and 102 boys). The dietary differences on schooldays and weekend days are reported. In girls only small changes in nutritional habits were seen as they grew older. In boys there was a gradual increase in food intake with age. Overall, higher nutrient intakes could be seen on weekend days. The energy intake on weekend days was consistently higher for girls and boys in all age-groups. The proportional intakes of fat and sugar were rather high, especially on weekend days. The alcohol consumption increased with age for girls as well as boys, and was for some individuals extremely high (boys) on weekend days. The observed levels of intake compared with the recommendations showed a rather low intake of polyunsaturated fatty acids, polysaccharides and iron.


Assuntos
Comportamento do Adolescente , Inquéritos sobre Dietas , Inquéritos Nutricionais , Fenômenos Fisiológicos da Nutrição , Adolescente , Envelhecimento , Consumo de Bebidas Alcoólicas , Criança , Ingestão de Energia , Feminino , Humanos , Estudos Longitudinais , Masculino , Minerais/administração & dosagem , Países Baixos , Periodicidade , Vitaminas/administração & dosagem
16.
Ann Hum Biol ; 12(6): 545-9, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4091509

RESUMO

In a multi-discipline longitudinal study, 'Growth and Health of Teenagers', height velocity was measured four monthly during four consecutive years in a group of about 250 growing Dutch youngsters. From the individual velocity curves of height we calculated peak height velocity (PHV) and the age at which PHV occurred. Height velocity was estimated in 102 boys from the derivative of a second degree moving polynomial function over five measurements. PHV varies in boys between 6.1 and 14.0 cm/year. The median value of the age at PHV in boys is 14.0 years. Early-maturing boys have approximately 2 cm/year greater PHVs than late-maturing boys.


Assuntos
Estatura , Crescimento , Puberdade , Adolescente , Fatores Etários , Humanos , Masculino
17.
J Nucl Med ; 25(9): 984-6, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6470814

RESUMO

In a patient with a paraganglioma at the carotid bifurcation, intense uptake of meta-[I-131]iodobenzylguanidine (I-131 MIBG) in the tumor was found. There was no clinical or biochemical evidence for catecholamine secretion by the tumor, although analysis of the tissue revealed that catecholamine biosynthesis took place. We conclude that accumulation of I-131 MIBG may occur in a paraganglioma, but does not necessarily indicate endocrine activity of the tumor.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Radioisótopos do Iodo , Iodobenzenos , Paraganglioma/diagnóstico por imagem , 3-Iodobenzilguanidina , Idoso , Catecolaminas/metabolismo , Humanos , Iodobenzenos/metabolismo , Masculino , Paraganglioma/metabolismo , Radiografia , Cintilografia
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