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1.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36827568

RESUMO

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

2.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929235

RESUMO

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

3.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016715

RESUMO

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.

4.
Pharmazie ; 73(10): 605-608, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30223926

RESUMO

Drug incompatibilities can lead to loss of effectiveness of drugs or to increased risk for undesirable effects that can even be life-threatening. Especially children are at high risk. Databases are an important source of information in routine care to avoid incompatibilities. However, they were supposedly developed considering drugs for use in adults. Thus, we analysed to what extent databases are appropriate for the identification of incompatibilities in intravenous (i.v.) drug therapy in paediatric intensive care. We analysed the information provided by two databases (Database A and B) on all pairs of two drugs prescribed to be administered via the same i.v. access line in a university paediatric intensive care unit during the study period of 50 days. A total of 50 different i.v. drugs was prescribed in 318 different combinations (drug pairs). We found information on (in)compatibilities in 23.0 % (73/318) in Database A and in 31.1 % (99/318) in Database B. Only in 11.0 % (35/318) of the drug pairs, both databases provided information. Considering those drug pairs, in 17.1 % (6/35) Database B indicated compatibility whereas Database A indicated incompatibility. Compatibility information delivered by databases on drugs used in paediatric intensive care is incomplete, heterogeneous, and partly contradictory. Thus, an increased awareness on the strengths and limitations of different databases is necessary to avoid patient harm.


Assuntos
Incompatibilidade de Medicamentos , Unidades de Terapia Intensiva Pediátrica/normas , Adolescente , Criança , Pré-Escolar , Bases de Dados Factuais , Serviços de Informação sobre Medicamentos , Quimioterapia Combinada , Humanos , Lactente , Recém-Nascido , Infusões Intravenosas , Adulto Jovem
5.
Phys Rev Lett ; 107(17): 171104, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22107501

RESUMO

We report the observation of a steepening in the cosmic ray energy spectrum of heavy primary particles at about 8×10(16) eV. This structure is also seen in the all-particle energy spectrum, but is less significant. Whereas the "knee" of the cosmic ray spectrum at 3-5×10(15) eV was assigned to light primary masses by the KASCADE experiment, the new structure found by the KASCADE-Grande experiment is caused by heavy primaries. The result is obtained by independent measurements of the charged particle and muon components of the secondary particles of extensive air showers in the primary energy range of 10(16) to 10(18) eV. The data are analyzed on a single-event basis taking into account also the correlation of the two observables.

6.
Dev Ophthalmol ; 46: 111-122, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20703037

RESUMO

Macular edema is an abnormal thickening of the macula associated with the accumulation of excess fluid in the extracellular space of the neurosensory retina. The following chapter looks at the basic pathomechanisms of macular edema as well as major pathologic conditions leading to it: special focus is on diabetic retinopathy, retinal venous occlusions and a number of inflammatory disorders. Currently available data on up-to-date pharmacologic treatment options such as steroids and anti-VEGF compounds is presented and discussed.


Assuntos
Edema Macular/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Bevacizumab , Catarata/complicações , Extração de Catarata/efeitos adversos , Retinopatia Diabética/complicações , Angiofluoresceinografia , Humanos , Edema Macular/diagnóstico , Edema Macular/etiologia , Edema Macular/fisiopatologia , Ranibizumab , Oclusão da Veia Retiniana/complicações , Esteroides/uso terapêutico , Tomografia de Coerência Óptica
7.
Microvasc Res ; 79(2): 150-3, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20053365

RESUMO

BACKGROUND: Retinal microvascular changes predict cardiovascular morbidity and mortality independent of classical risk factors. However, it is unclear which retinal changes characterize patients with established coronary artery disease (CAD), and in particular, with acute coronary syndromes (ACS). The aim of the present preliminary study was to assess retinopathy in these patients. METHODS: 43 consecutive patients with ACS and 19 consecutive patients with stable CAD were investigated. Among the patient group with ACS, 20 patients presented with ST-Elevation Myocardial Infarction (STEMI) and 23 patients presented with Non-STEMI (NSTEMI). Standardized protocols were used and retinal fundus photography was taken within 48 h post-coronary angiography to assess retinopathy and general arteriolar narrowing as arterio-venous ratio (AVR). Clinical and laboratory cardiovascular risk factors were recorded. RESULTS: Despite comparable age and comparable frequency of diabetes and hypertension, patients with ACS had a much higher likelihood for retinal microaneurysms and dot bleedings than patients with stable CAD (17 (40%) vs. 1 (5%) patients, OR 11.77; 95%CI 1.43-96.59; p=0.006). Performing multivariate analysis, this association remains significant (OR 20.5, 95%CI 1.6-255, p=0.019). CAD patients presented more often with focal signs of arteriovenous nicking / focal vasoconstriction (10 (53%) vs. 9 (21%) patients, OR 4.2; 95%CI 1.31-13.4; p=0.018), however after multivariate analysis this association lost significance. The AVR was comparably low in both groups. CONCLUSION: Patients with ACS present more often with dot bleedings and microaneurysms. These findings provide preliminary evidence that retinal fundus examination may be useful to contribute to the risk profile of patients, enabling a more intensive survey and care.


Assuntos
Síndrome Coronariana Aguda/patologia , Doença da Artéria Coronariana/patologia , Microvasos/patologia , Doenças Retinianas/patologia , Vasos Retinianos/patologia , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/fisiopatologia , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Masculino , Microcirculação , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Doenças Retinianas/complicações , Doenças Retinianas/fisiopatologia , Vasos Retinianos/fisiopatologia
8.
Eur J Ophthalmol ; 18(5): 778-86, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18850558

RESUMO

PURPOSE: Efficacy, safety, and cost implications are important considerations when choosing an ophthalmic treatment. Fixed-combination glaucoma medications containing brimonidine 0.2% and timolol 0.5%, or dorzolamide 2% and timolol 0.5%, were compared with brimonidine 0.2% and dorzolamide 2% that were used as adjunctive therapy to timolol 0.5%. METHODS: A literature review was conducted to determine the outcome parameters of intraocular pressure reduction and tolerability after 3 months of use of brimonidine or dorzolamide, each together with timolol as a fixed-combination or in concomitant therapy. Modelled cost-minimization and cost-effectiveness analyses were performed to investigate the economic consequences of ophthalmic therapy with brimonidine, dorzolamide, and timolol from a societal perspective. RESULTS: The literature review found that brimonidine and dorzolamide used as fixed combinations with timolol as well as in adjunctive therapy to timolol were equally effective and safe. Furthermore, in the European countries studied, the fixed combination of brimonidine/timolol represented a less costly option when compared to the fixed combination of dorzolamide/timolol evaluated over both a 3-month and a 12-month horizon. CONCLUSIONS: Brimonidine used as a fixed-combination therapy with timolol provided better cost value than dorzolamide/timolol in all the countries studied. For most countries, the fixed combination of brimonidine and timolol also provided better cost value than adjunctive therapy with brimonidine, which was more cost effective than adjunctive therapy with dorzolamide.


Assuntos
Anti-Hipertensivos/economia , Custos de Medicamentos , Glaucoma de Ângulo Aberto/economia , Soluções Oftálmicas/economia , Anti-Hipertensivos/efeitos adversos , Tartarato de Brimonidina , Análise Custo-Benefício , Combinação de Medicamentos , Quimioterapia Combinada , Europa (Continente) , Glaucoma de Ângulo Aberto/tratamento farmacológico , Custos de Cuidados de Saúde , Humanos , Pressão Intraocular/efeitos dos fármacos , Pessoa de Meia-Idade , Programas Nacionais de Saúde/economia , Soluções Oftálmicas/efeitos adversos , Quinoxalinas/efeitos adversos , Quinoxalinas/economia , Sulfonamidas/efeitos adversos , Sulfonamidas/economia , Tiofenos/efeitos adversos , Tiofenos/economia , Timolol/efeitos adversos , Timolol/economia , Resultado do Tratamento
9.
Curr Med Res Opin ; 24(6): 1763-70, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18559164

RESUMO

OBJECTIVE: The purpose of this study was to estimate costs and quality of life (QoL) of late-stage glaucoma patients in 4 European countries. METHODS: Retrospective review of medical charts of patients with POAG who were followed in a low-vision or vision rehabilitation center in one of 4 countries for at least 1 year was used to determine patient characteristics, health status, and health care resource use. Visual impairment was measured by best-corrected visual acuity (Snellen score). Patients were also interviewed over the telephone in order to assess their health-related QoL (using EuroQol EQ-5D) and use of resources including: the number of visits to rehabilitation centers, visits to hospital and non-hospital specialists, the use of low-vision devices, medication, tests, and the use of hired home help. The costs associated with resource use were calculated from the perspective of a third-party payer of health and social care based on resource usage and unit costs in each country. RESULTS: Patients undergoing visual rehabilitation in France (n=21), Denmark (n=59), Germany (n=60), and the United Kingdom (n=22) were identified, interviewed and had their medical charts reviewed. Annual maintenance costs of late-stage glaucoma amounted to euro830 (+/-445) on average. Average home help costs were more than 3 times higher. QoL, on average, was 0.65 (+/-0.28). QoL was positively correlated with the level of visual acuity in the patients' best eye. On the other hand, visual acuity was also positively correlated to health care costs, but negatively correlated to costs of home help. CONCLUSIONS: The study was limited by its observational, uncontrolled design. The finding that late-stage glaucoma is associated with higher home help costs than health care maintenance costs suggests that potential savings from a better preventive treatment are to be found for social care payers rather than health care payers.


Assuntos
Efeitos Psicossociais da Doença , Glaucoma/classificação , Glaucoma/economia , Gastos em Saúde , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Glaucoma/fisiopatologia , Glaucoma/reabilitação , Gastos em Saúde/estatística & dados numéricos , Serviços de Saúde/estatística & dados numéricos , Nível de Saúde , Humanos , Entrevistas como Assunto , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Estudos Retrospectivos , Tecnologia Assistiva/estatística & dados numéricos
10.
Curr Med Res Opin ; 24(4): 1057-63, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18315942

RESUMO

OBJECTIVE: To compare the efficacy and cost implications of the use of the intraocular pressure-lowering prostaglandin analogues bimatoprost, travoprost, and latanoprost as fixed-combination therapies with timolol, a beta-adrenergic receptor antagonist. METHODS: A decision analytic cost-effectiveness model was constructed. Since no head-to-head studies comparing the three treatment options exist, the analysis was based on an indirect comparison. Hence, the model was based on efficacy data from five randomized, controlled, clinical studies. The studies were comparable with respect to study design, time horizon, patient population and type of end point presented. The measure of effectiveness was the percentage reduction of the intraocular pressure level from baseline. The cost evaluated was the cost of medication and clinical visits to the ophthalmologist. All drug costs were market prices inclusive of value-added tax, and visit costs were priced using official physician fees. Cost-effectiveness analyses were carried out in five European countries: Spain, Italy, United Kingdom, Norway and Sweden. The time horizon for the analyses was 3 months. RESULTS: The analysis showed that fixed-combination bimatoprost/timolol was more effective and less costly than fixed-combination travoprost/timolol and fixed-combination latanoprost/timolol in three out of the five countries analyzed. In two countries, bimatoprost/timolol was less costly than latanoprost/timolol, and cost the same as travoprost/timolol. CONCLUSIONS: This cost-effectiveness analysis showed that the fixed combination of bimatoprost 0.03%/timolol 0.5% administered once daily was a cost-effective treatment option for patients with primary open-angle glaucoma. This study was limited by available clinical data: without a head-to-head trial, indirect comparisons were necessary. In the United Kingdom, Sweden, Norway, Italy, and Spain, from a health service viewpoint, bimatoprost/timolol was a slightly more effective as well as less costly treatment strategy when compared to both travoprost/timolol and latanoprost/timolol.


Assuntos
Anti-Hipertensivos/economia , Anti-Hipertensivos/uso terapêutico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Glaucoma de Ângulo Aberto/economia , Pressão Intraocular/efeitos dos fármacos , Antagonistas Adrenérgicos beta/economia , Antagonistas Adrenérgicos beta/uso terapêutico , Amidas/economia , Amidas/uso terapêutico , Bimatoprost , Cloprostenol/análogos & derivados , Cloprostenol/economia , Cloprostenol/uso terapêutico , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Quimioterapia Combinada , Europa (Continente) , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Latanoprosta , Modelos Econômicos , Prostaglandinas F Sintéticas/economia , Prostaglandinas F Sintéticas/uso terapêutico , Prostaglandinas Sintéticas/uso terapêutico , Timolol/economia , Timolol/uso terapêutico , Travoprost
11.
Eur J Ophthalmol ; 18(1): 52-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18203085

RESUMO

PURPOSE: This study describes the treatment in ordinary clinical practice in Spain of patients with glaucoma with a two-drug combination therapy. The authors present the treatment outcome as endof-period intraocular pressure (IOP) and the calculated direct medical costs over a 2-year period. METHODS: Data were extracted retrospectively from patient charts recording the use of all medical resources related to glaucoma. Costs were estimated using unit costs from public sources (2005). Descriptive cost analysis according to combination treatment at baseline was performed. RESULTS: The study included 216 patients from 21 centers. Around half of the patients were started on a beta-blocker/prostaglandin analogue combination, while the rest received various other combinations containing either an alpha2-agonist or a carbonic anhydrase inhibitor. Across the seven groups considered, there was a statistically significant difference in the costs of the least and the two most costly groups, while the confidence intervals were overlapping in all other pairwise comparisons. The least costly drug combination was brimonidine/timolol. Assessing IOP at the end of follow-up, all the groups were equally effective (overlapping confidence intervals). In a multivariate regression analysis, the drug combination did not have an independent, significant impact on total direct medical costs, drug costs, or end-of-period IOP. Significant determinants of these variables were surgical interventions and one or more changes of drug combination during the follow-up. CONCLUSIONS: Costs are determined by the response to treatment. Inadequate response triggers treatment changes and sometimes eventually surgical interventions, thereby increasing costs significantly.


Assuntos
Anti-Hipertensivos/economia , Efeitos Psicossociais da Doença , Custos de Medicamentos , Glaucoma de Ângulo Aberto/economia , Administração Tópica , Adulto , Idoso , Custos e Análise de Custo , Quimioterapia Combinada , Feminino , Glaucoma de Ângulo Aberto/tratamento farmacológico , Humanos , Pressão Intraocular/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/tratamento farmacológico , Hipertensão Ocular/economia , Soluções Oftálmicas/economia , Estudos Retrospectivos , Espanha , Resultado do Tratamento
12.
Br J Ophthalmol ; 91(6): 766-72, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17229802

RESUMO

AIM: To investigate the relative priorities in quality of life (QoL) in patients with age-related macular degeneration (AMD). METHODS: Measures of visual function, QoL and utility associated with visual loss were obtained from 122 patients with AMD classified according to macular morphology. The two methods of utility assessment were time trade-off (TTO) and conjoint analysis (CA), which have been recommended by the UK's National Institute of Clinical Excellence as techniques for the assessment of healthcare priorities. RESULTS: Results show that the two methods for assessing utility are poorly related: TTO relates moderately to visual function and disease severity but CA does not. CA identified two different subgroups of patients: one with outdoor mobility and the other with reading as their main priority. CONCLUSION: Further work is needed and caution required in interpreting data obtained using these methodologies for determining their relative importance in vision-related QoL studies.


Assuntos
Indicadores Básicos de Saúde , Degeneração Macular/reabilitação , Qualidade de Vida , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Comportamento de Escolha , Feminino , Humanos , Degeneração Macular/psicologia , Masculino , Índice de Gravidade de Doença , Visão Binocular , Acuidade Visual
13.
Br J Ophthalmol ; 89(10): 1245-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16170109

RESUMO

BACKGROUND: Resource utilisation and direct costs associated with glaucoma progression in Europe are unknown. As population progressively ages, the economic impact of the disease will increase. METHODS: From a total of 1655 consecutive cases, the records of 194 patients were selected and stratified by disease severity. Record selection was based on diagnoses of primary open angle glaucoma, glaucoma suspect, ocular hypertension, or normal tension glaucoma; 5 years minimum follow up were required. Glaucoma severity was assessed using a six stage glaucoma staging system based on static threshold visual field parameters. Resource utilisation data were abstracted from the charts and unit costs were applied to estimate direct costs to the payer. Resource utilisation and estimated direct cost of treatment, per person year, were calculated. RESULTS: A statistically significant increasing linear trend (p = 0.018) in direct cost as disease severity worsened was demonstrated. The direct cost of treatment increased by an estimated 86 for each incremental step ranging from 455 euro per person year for stage 0 to 969 euro per person year for stage 4 disease. Medication costs ranged from 42% to 56% of total direct cost for all stages of disease. CONCLUSIONS: These results demonstrate for the first time in Europe that resource utilisation and direct medical costs of glaucoma management increase with worsening disease severity. Based on these findings, managing glaucoma and effectively delaying disease progression would be expected to significantly reduce the economic burden of this disease. These data are relevant to general practitioners and healthcare administrators who have a direct influence on the distribution of resources.


Assuntos
Glaucoma/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Recursos em Saúde/estatística & dados numéricos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Custos de Medicamentos/estatística & dados numéricos , Europa (Continente) , Feminino , Seguimentos , Glaucoma/fisiopatologia , Glaucoma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Visita a Consultório Médico/economia , Índice de Gravidade de Doença , Distribuição por Sexo , Campos Visuais
14.
Int J Clin Pract ; 59(9): 1011-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16115174

RESUMO

Glaucoma is a condition affecting one or both eyes with raised intraocular pressure (IOP). IOP should be reduced to prevent progression of visual field loss. This study investigates the cost-effectiveness of bimatoprost compared with latanoprost as first-line monotherapies in the treatment of glaucoma in Austria, Finland and France. On the basis of a single multicentre, randomised, investigator-masked controlled trial, a 6- and 12-month cost-effectiveness model was designed following the treatment recommendations from the European Glaucoma Society. Treatment changes due to insufficient IOP reduction and adverse events were included. The cost-effectiveness analysis showed that the need for adjunctive therapy was the major cost driver. On the basis of evidence from the randomised, investigator-masked clinical trial (RCT), the cost-effectiveness analysis found that bimatoprost was a cheaper and a more effective treatment strategy compared with latanoprost. This was true for all three countries and all IOP targets between 13 and 20 mmHg. The cost-effectiveness result may be generalised to a European setting and perspective.


Assuntos
Anti-Hipertensivos/economia , Glaucoma/tratamento farmacológico , Lipídeos/economia , Modelos Econômicos , Amidas , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/uso terapêutico , Áustria , Bimatoprost , Quimioterapia Adjuvante/economia , Cloprostenol/análogos & derivados , Análise Custo-Benefício , Custos de Medicamentos , Finlândia , França , Humanos , Latanoprosta , Lipídeos/efeitos adversos , Lipídeos/uso terapêutico , Soluções Oftálmicas , Prostaglandinas F Sintéticas/efeitos adversos , Prostaglandinas F Sintéticas/economia , Prostaglandinas F Sintéticas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Nature ; 435(7040): 313-6, 2005 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-15902250

RESUMO

The nature of ultrahigh-energy cosmic rays (UHECRs) at energies >10(20) eV remains a mystery. They are likely to be of extragalactic origin, but should be absorbed within approximately 50 Mpc through interactions with the cosmic microwave background. As there are no sufficiently powerful accelerators within this distance from the Galaxy, explanations for UHECRs range from unusual astrophysical sources to exotic string physics. Also unclear is whether UHECRs consist of protons, heavy nuclei, neutrinos or gamma-rays. To resolve these questions, larger detectors with higher duty cycles and which combine multiple detection techniques are needed. Radio emission from UHECRs, on the other hand, is unaffected by attenuation, has a high duty cycle, gives calorimetric measurements and provides high directional accuracy. Here we report the detection of radio flashes from cosmic-ray air showers using low-cost digital radio receivers. We show that the radiation can be understood in terms of the geosynchrotron effect. Our results show that it should be possible to determine the nature and composition of UHECRs with combined radio and particle detectors, and to detect the ultrahigh-energy neutrinos expected from flavour mixing.

16.
Phys Rev Lett ; 93(21): 212003, 2004 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-15600999

RESUMO

We have searched for Theta+(1540) and Xi(--)(1862) pentaquark candidates in proton-induced reactions on C, Ti, and W targets at midrapidity and square root of s = 41.6 GeV. In 2 x 10(8) inelastic events we find no evidence for narrow (sigma approximately 5 MeV) signals in the Theta+ --> pK0(S) and Xi(--) --> Xi- pi- channels; our 95% C.L. upper limits (UL) for the inclusive production cross section times branching fraction B dsigma/dy/(y approximately 0) are (4-16) mub/N for a Theta+ mass between 1521 and 1555 MeV, and 2.5 mub/N for the Xi(--). The UL of the yield ratio of Theta+/Lambda(1520) < (3-12)% is significantly lower than model predictions. Our UL of B Xi(--)/Xi(1530)0 < 4% is at variance with the results that have provided the first evidence for the Xi(--).

19.
Zentralbl Neurochir ; 55(2): 71-8, 1994.
Artigo em Alemão | MEDLINE | ID: mdl-7941829

RESUMO

Tuberculosis is relative uncommon in developed countries. The incidence is still considerable in India, in the Middle East and South America. Neurosurgically important manifestations of tuberculosis are intracranial tuberculomas, tuberculous meningitis with hydrocephalus and tuberculous spondylitis. Therefore experiences in the management of these three kinds of neurotuberculosis are described and an overview of the literature is given. The diagnosis of intracranial tuberculomas is difficult because the symptoms are similar to those of many other types of intracranial tumor and the CT-findings are unspecific. Clinical recognition of neurotuberculosis rests mainly on the evidence of the general disease. A positive skin test supports the diagnosis. The management of tuberculomas enclosed stereotactic biopsy to confirm the diagnosis, medical treatment and surgery. But surgery is only indicated for larger symptomatic mass lesions producing midline shift and severe intracranial hypertension. With antituberculous drugs treated tuberculomas begin to decrease in size within the first two months of therapy. Hydrocephalus is a common complication of tuberculous meningitis. Due to the low incidence the first diagnosis in industrialized countries is a hydrocephalus of unknown origin. The diagnosis of tuberculous meningitis is suspected in any case of subacute meningitis with a CSF profile demonstrating a predominance of lymphocytes, elevated protein value, hypoglycaemia and negative stains for bacterial or fungal organisms, because positive smears for acid-fast bacilli are seldom. Without treatment, tuberculous meningitis is invariably fatal within 4 to 6 weeks. Therefore, when ever tuberculous meningitis is suspected, antituberculous therapy must be started.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Tuberculoma Intracraniano/cirurgia , Tuberculose Meníngea/cirurgia , Tuberculose da Coluna Vertebral/cirurgia , Adulto , Idoso , Encéfalo/patologia , Diagnóstico Diferencial , Feminino , Humanos , Hidrocefalia/patologia , Hidrocefalia/cirurgia , Masculino , Coluna Vertebral/patologia , Tuberculose Meníngea/patologia , Tuberculose da Coluna Vertebral/patologia
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