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1.
Appl Microbiol Biotechnol ; 104(1): 131-144, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31781817

RESUMO

The availability of bioresources is a precondition for life science research, medical applications, and diagnostics, but requires a dedicated quality management to guarantee reliable and safe storage. Anecdotal reports of bacterial isolates and sample contamination indicate that organisms may persist in liquid nitrogen (LN) storage tanks. To evaluate the safety status of cryocollections, we systematically screened organisms in the LN phase and in ice layers covering inner surfaces of storage tanks maintained in different biobanking facilities. We applied a culture-independent approach combining cell detection by epifluorescence microscopy with the amplification of group-specific marker genes and high-throughput sequencing of bacterial ribosomal genes. In the LN phase, neither cells nor bacterial 16S rRNA gene copy numbers were detectable (detection limit, 102 cells per ml, 103 gene copies per ml). In several cases, small numbers of bacteria of up to 104 cells per ml and up to 106 gene copies per ml, as well as Mycoplasma, or fungi were detected in the ice phase formed underneath the lids or accumulated at the bottom. The bacteria most likely originated from the stored materials themselves (Elizabethingia, Janthibacterium), the technical environment (Pseudomonas, Acinetobacter, Methylobacterium), or the human microbiome (Bacteroides, Streptococcus, Staphylococcus). In single cases, bacteria, Mycoplasma, fungi, and human cells were detected in the debris at the bottom of the storage tanks. In conclusion, the limited microbial load of the ice phase and in the debris of storage tanks can be effectively avoided by minimizing ice formation and by employing hermetically sealed sample containers.


Assuntos
Bancos de Espécimes Biológicos/normas , Criopreservação/instrumentação , Contaminação de Equipamentos , Nitrogênio , Bactérias/genética , Carga Bacteriana , DNA Bacteriano/genética , Fungos/genética , Humanos , Gelo , Limite de Detecção , RNA Ribossômico 16S
2.
Cryo Letters ; 39(6): 345-353, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30963150

RESUMO

BACKGROUND: Vitrification approaches are widely used to cryopreserve Mentha spp. genetic resources. OBJECTIVE: Here, we compared the response of 20 different Mentha species and hybrids during cryopreservation and elucidated the efficacy of two cryoprotectants. MATERIALS AND METHODS: One hundred and fifty three Mentha spp. accessions were cryopreserved using in vitro plants maintained under slow-growth storage and PVS2 or PVS3 as cryoprotectants. RESULTS: The cryoprotectant PVS2 was effective for all species, except M. requienii and M. villosanervata. The use of PVS3 increased the proportion of explants able to regrow after rewarming. The outbreak of endophytes upon rewarming was both less frequent and less severe when PVS3 replaced PVS2. CONCLUSION: Both PVS2 and PVS3 can be used as cryoprotectant for all the species and accessions of Mentha spp. surveyed. Since higher regenerations were achieved using PVS3, and since the risk of an endophyte outbreak was reduced, this cryoprotectant should be preferred in future for cryopreserving Mentha spp.


Assuntos
Criopreservação/métodos , Crioprotetores/química , Mentha , Vitrificação , Brotos de Planta
3.
Klin Padiatr ; 229(1): 32-39, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27723910

RESUMO

Infants exposed to opiates antenatally display withdrawal symptoms after birth referred to as neonatal abstinence syndrome (NAS).A total of 366 newborns (166 females, 10 twins) from 361 mothers were diagnosed with NAS from 2000 to 2011 at a single large metropolitan referral center.Retrospective chart review of all newborn infants exposed to opiates in utero.20% were premature (gestational age<37 weeks), 32% were small-for-gestational-age (<10th percentile). 70% of infants (195/278) antenatally exposed to methadone (racemic methadone or levomethadone) required pharmacological treatment for 11 (1-55) days (median; range); however, 45% of infants (28/62) exposed to buprenorphine required pharmacological treatment for a median of only 5 (1-20) days (p=0.014). Pharmacological treatment of infants with phenobarbital (n=189) took a median of 9 (1-53) days, but treatment with morphine (n=39) took 19 (3-55) days (p<0.001). The median duration of hospitalization increased from 11 days in 2000-2004 to 19 days in 2008-2011 (p<0.001). The increased durations of neonatal hospitalization were associated with similar increases in the average dosages of maternal methadone.Use of buprenorphine, rather than methadone, for treatment of opiate-addicted pregnant women is associated with fewer and shorter neonatal withdrawal symptoms. The duration of hospitalization and treatment for NAS has increased over time.


Assuntos
Síndrome de Abstinência Neonatal/reabilitação , Transtornos Relacionados ao Uso de Opioides/reabilitação , Encaminhamento e Consulta , Centros de Tratamento de Abuso de Substâncias , Buprenorfina/efeitos adversos , Buprenorfina/uso terapêutico , Doenças em Gêmeos/diagnóstico , Doenças em Gêmeos/reabilitação , Feminino , Hospitalização , Humanos , Recém-Nascido , Masculino , Metadona/efeitos adversos , Metadona/uso terapêutico , Morfina/efeitos adversos , Morfina/uso terapêutico , Síndrome de Abstinência Neonatal/diagnóstico , Transtornos Relacionados ao Uso de Opioides/diagnóstico , Fenobarbital/efeitos adversos , Fenobarbital/uso terapêutico , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
4.
Cryo Letters ; 38(5): 364-371, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29734403

RESUMO

  BACKGROUND: The use of the model plant Arabidopsis could be a valuable tool to elucidate the basic mechanisms involved in plant cryopreservation. OBJECTIVE: A simple and powerful protocol, independent of Arabidopsis genotypes, was established using a PVS2 protocol. MATERIALS AND METHODS: Two PVS2 (a and b), one PVS3 droplet-vitrification and one DMSO droplet-freezing protocol were tested with alternating temperatures during the growing phase of donor plants. RESULTS: PVS2 protocols, including cold acclimation of donor plants, resulted in highest recovery. The PVS2a protocol was successfully applied to a collection of different Arabidopsis genotypes with an average recovery of 94%. In addition, Differential Scanning Calorimetry confirmed the occurrence of glass transitions in the PVS3 and PVS2 protocols. CONCLUSION: The PVS2a protocol is suitable to screen the large collection of Arabidopsis mutants and transgenic lines with the aim to identify cellular functions associated with cryopreservation tolerance.


Assuntos
Arabidopsis/genética , Arabidopsis/fisiologia , Criopreservação/métodos , Brotos de Planta/fisiologia , Arabidopsis/efeitos dos fármacos , Crioprotetores/farmacologia , Cristalização , Ecótipo , Congelamento , Genótipo , Brotos de Planta/efeitos dos fármacos , Vitrificação
5.
Clin Genet ; 88(5): 456-61, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25307543

RESUMO

Pathogenic mutations in genes COL4A3/COL4A4 are responsible for autosomal Alport syndrome (AS) and thin basement membrane nephropathy (TBMN). We used Sanger sequencing to analyze all exons and splice site regions of COL4A3/COL4A4, in 40 unrelated Portuguese probands with clinical suspicion of AS/TBMN. To assess genotype-phenotype correlations, we compared clinically relevant phenotypes/outcomes between homozygous/compound heterozygous and apparently heterozygous patients. Seventeen novel and four reportedly pathogenic COL4A3/COL4A4 mutations were identified in 62.5% (25/40) of the probands. Regardless of the mutated gene, all patients with ARAS manifested chronic renal failure (CRF) and hearing loss, whereas a minority of the apparently heterozygous patients had CRF or extrarenal symptoms. CRF was diagnosed at a significantly younger age in patients with ARAS. In our families, the occurrence of COL4A3/COL4A4 mutations was higher, while the prevalence of XLAS was lower than expected. Overall, a pathogenic COL4A3/COL4A4/COL4A5 mutation was identified in >50% of patients with fewer than three of the standard diagnostic criteria of AS. With such a population background, simultaneous next-generation sequencing of all three genes may be recommended as the most expedite approach to diagnose collagen IV-related glomerular basement membrane nephropathies.


Assuntos
Autoantígenos/genética , Colágeno Tipo IV/genética , Hematúria/genética , Mutação , Nefrite Hereditária/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Mutacional de DNA , Exoma , Feminino , Estudos de Associação Genética , Hematúria/diagnóstico , Hematúria/metabolismo , Humanos , Falência Renal Crônica/genética , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Nefrite Hereditária/diagnóstico , Nefrite Hereditária/metabolismo , Portugal , Adulto Jovem
7.
Parasitol Res ; 114(3): 1129-37, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25592754

RESUMO

Following studies on the transmission of Onchocerca volvulus (Leuckart) by Simulium sanctipauli Vajime & Dunbar (Diptera, Simuliidae) in Upper Denkyira District in Ghana in 2001 and 2002 (Kutin et al., Med Vet Ent 18:167-173, 2004), further assessments were carried out in 2006 and 2013/2014 to determine whether transmission parameters had changed since community-directed ivermectin treatment (CDTI) began in 1999. There were no marked changes of the transmission intensities in 2006. Only slight, but non-significant, reductions were observed in infection rates of parous flies with larval stages (L1-L3) of O. volvulus from 44.1 % (of 1672 parous flies) in 2001/2002 to 42.1 % (506) in 2006 and from 6.5 to 5.9 % of flies carrying infective larvae in their heads. This suggested that there was an ongoing transmission in the area and the parasite reservoir in the human population was still high. Unexpectedly, further assessments conducted in October 2013 and March and October 2014 revealed that the vector S. sanctipauli had apparently disappeared and transmission had ceased, probably as a result of intensified gold mining activities along the rivers Ofin and Pra. The water of both rivers was extremely turbid, heavily loaded with suspended solids, probably preventing the development of blackfly larvae. Some breeding and biting of Simulium yahense Vajime & Dunbar was observed in a small tributary of the Pra, the Okumayemfuo, which is not affected by gold mining. However, the infection rate of flies was low, only 3.7 % of 163 parous flies were infected with first stage (L1) larvae of O. volvulus.


Assuntos
Insetos Vetores/parasitologia , Inseticidas/farmacologia , Ivermectina/farmacologia , Onchocerca volvulus/fisiologia , Oncocercose/transmissão , Simuliidae/parasitologia , Animais , Cruzamento , Feminino , Geografia , Gana/epidemiologia , Humanos , Larva , Oncocercose/prevenção & controle , Rios
8.
Fortschr Neurol Psychiatr ; 83(7): 373-80, 2015 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-26200042

RESUMO

BACKGROUND: Neuroleptic malignant syndrome (NMS) is a rare but potentially life-threatening medication-induced syndrome. Core symptoms are hyperthermia, diaphoresis, rigidity, impaired consciousness, and creatinine kinase elevation. Additionally, patients show vegetative dysregulation including blood pressure fluctuations. The purpose of this paper is to summarize current findings, to facilitate diagnostics and to distinguish NMS from other syndromes. METHODS: We performed a systematic review of the literature. We included scientific publications, books and guidelines. RESULTS: In this review we summarize the current diagnostic criteria, differential diagnosis, pathogenesis and therapeutic options. CONCLUSION: Clinical symptoms of NMS are heterogeneous and it is difficult to diagnose early states. Early interventions are important to ensure fast and complete recovery. Since NMS is a rare condition, publications on NMS-therapy are based on single-case reports, meta-analysis or expert opinions. Core symptoms should be considered: Exposure to dopamine-antagonists, hyperthermia, diaphoresis, rigidity, mental status alteration, creatinine kinase elevation, and vegetative dysregulation.


Assuntos
Antipsicóticos/efeitos adversos , Síndrome Maligna Neuroléptica/terapia , Diagnóstico Diferencial , Humanos , Síndrome Maligna Neuroléptica/diagnóstico , Síndrome Maligna Neuroléptica/epidemiologia , Fatores de Risco
9.
Nat Commun ; 15(1): 2655, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531894

RESUMO

Genetic pleiotropy is abundant across spatially distributed brain characteristics derived from one neuroimaging modality (e.g. structural, functional or diffusion magnetic resonance imaging [MRI]). A better understanding of pleiotropy across modalities could inform us on the integration of brain function, micro- and macrostructure. Here we show extensive genetic overlap across neuroimaging modalities at a locus and gene level in the UK Biobank (N = 34,029) and ABCD Study (N = 8607). When jointly analysing phenotypes derived from structural, functional and diffusion MRI in a genome-wide association study (GWAS) with the Multivariate Omnibus Statistical Test (MOSTest), we boost the discovery of loci and genes beyond previously identified effects for each modality individually. Cross-modality genes are involved in fundamental biological processes and predominantly expressed during prenatal brain development. We additionally boost prediction of psychiatric disorders by conditioning independent GWAS on our multimodal multivariate GWAS. These findings shed light on the shared genetic mechanisms underlying variation in brain morphology, functional connectivity, and tissue composition.


Assuntos
Estudo de Associação Genômica Ampla , Neuroimagem , Humanos , Estudo de Associação Genômica Ampla/métodos , Fenótipo , Pleiotropia Genética , Encéfalo/anatomia & histologia , Polimorfismo de Nucleotídeo Único , Predisposição Genética para Doença
10.
J Clin Med ; 13(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38929972

RESUMO

Background: Mycoplasma pneumoniae (M. pneumoniae) infections can progress to severe respiratory complications, necessitating intensive care treatment. Recent post COVID-19 pandemic surges underscore the need for timely diagnosis, given potential diagnostic method limitations. Methods: A retrospective case series analysis was conducted on M. pneumonia PCR-positive patients admitted to two Dutch secondary hospitals' ICUs between January 2023 and February 2024. Clinical presentations, treatments, outcomes, and mechanical ventilation data were assessed. Results: Seventeen ICU-admitted patients were identified, with a median age of 44 years, primarily due to hypoxia. Non-invasive ventilation was effective for most, while five required invasive mechanical ventilation. None of the patients required extracorporeal membrane oxygenation. No fatalities occurred. Post-PCR, treatment was adjusted to doxycycline or azithromycin; seven received steroid treatment. Discussion: Increased ICU admissions for M. pneumoniae infection were observed. Diverse clinical and radiological findings emphasize heightened clinical awareness. Early molecular diagnostics and tailored antibiotic regimens are crucial since beta-lactam antibiotics are ineffective. Conclusion: This study highlights the escalating challenge of severe M. pneumoniae infections in ICUs, necessitating a multifaceted approach involving accurate diagnostics, vigilant monitoring, and adaptable treatment strategies for optimal patient outcomes.

11.
Klin Monbl Augenheilkd ; 230(12): 1238-46, 2013 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-24104960

RESUMO

BACKGROUND: For an implemented ophthalmological screening within a German long-term cohort study (National Cohort) simple and effective methods for an examination of visual acuity and for non-mydriatic retina photografies should be evaluated. Furthermore standard operating-procedures (SOP) should be developed. METHODS: In the years 2011 and 2012 pinhole visual acuity measurements and automated retina photographies (DRS, CenterVue S. p. a., Padua, Italy) were made at three different epidemiological study centers within Germany. Furthermore, anterior segment images were taken by the camera. Standard operating procedures (SOP) regarding the ophthalmological screening were developed and evaluated within the study. The main question was whether it is possible to implement the screening methods within the National Cohort. Further main outcomes were quality and interpretability of the taken images. RESULTS: 457 subjects (914 eyes) were examined within the investigation. Median VA was 0.8 for right and left eyes (p > 0.42). Image quality of the photographies was good in 491 cases (54 %), fair in 239 cases (26 %) and bad in 179 cases (20 %). The usability of the images was without limitations in 686 cases (75 %), limited in 152 cases (17 %) and not given in 71 cases (8 %). Increasing age of the subjects was slightly correlated with decreasing image quality (r = 0.26) and decreasing image usability (r = 0.2). Anterior segment photographies were usable in 176 eyes (56 %). CONCLUSION: The developed screening method fulfilled the specifications of the National Cohort. The used pinhole visual acuity examination was fast and cheap. Image quality and usability of the retina photographies could be improved with prolonged pupil recovery times. The quality of the anterior segment images could not fulfill the expectations and were taken out of the further examinations of the ophthalmological screening. The written SOP showed good acceptance within the investigators' daily routine. The ophthalmological screening within the National Cohort generates information (e. g., pathologies of the vessels or of the retina) which are useful not only from an ophthalmological point of view.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Programas de Rastreamento/economia , Retinoscopia/economia , Transtornos da Visão/diagnóstico , Transtornos da Visão/economia , Testes Visuais/economia , Adulto , Idoso , Estudos de Coortes , Análise Custo-Benefício , Feminino , Alemanha , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Programas Nacionais de Saúde/economia , Projetos Piloto , Reprodutibilidade dos Testes , Retinoscopia/métodos , Sensibilidade e Especificidade , Transtornos da Visão/prevenção & controle , Testes Visuais/métodos , Adulto Jovem
12.
J ISAKOS ; 8(4): 227-231, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36924828

RESUMO

Distal biceps tendon ruptures are relatively rare injuries but tend to occur in active and athletic populations, especially in weightlifting and contact sports. The distal biceps tendon is an important supinator of the forearm and flexor of the elbow, thus an injury to this ligament can be invalidating for athletes. The aim of this review was to determine the ability and the time to return to sports following distal biceps tendon repair in athletes and the level of performance. The literature is scarce about the return to sports among athletes. Most studies include athletes are National Football League (NFL) players, others are weightlifters and a few recreational athletes. The return to play rate after distal biceps tendon repair is high. The performances of the returned players were similar to matched players and most players returned to the same level. Most players-depending on the sport-were not able to return to competition within the same season. In order to manage expectations, it should be discussed preoperatively with the athlete (and their coach) that the return to sports rate is high, but the return will probably be the following season.


Assuntos
Tendão do Calcâneo , Futebol Americano , Humanos , Volta ao Esporte , Cotovelo/cirurgia , Futebol Americano/lesões , Tendão do Calcâneo/lesões , Tendão do Calcâneo/cirurgia
13.
Urologe A ; 61(2): 183-186, 2022 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-34605930

RESUMO

BACKGROUND: Therapy of epitheloid angiomyolipomas (eAML) may be challenging, since unlike classical angiomyolipomas this rare subclass of benign mesenchymal angiomyolipomas may present with lymph node metastases, local recurrent disease, and/or systemic metastatic disease in up to 30% of cases. OBJECTIVES: We report here for the first time in Germany a case of eAML after successful treatment of malignant melanoma. MATERIALS AND METHODS: Clinical and histological findings as well as results of the genetic analysis of the angiomyolipoma are presented. RESULTS: A somatic, truncating mutation of the TSC2 gene was found in the angiomyolipoma. CONCLUSION: The relationship to histologically similar tumor entities are presented and therapeutic options based on the genetic classification are discussed.


Assuntos
Angiomiolipoma , Neoplasias Renais , Melanoma , Segunda Neoplasia Primária , Angiomiolipoma/diagnóstico por imagem , Angiomiolipoma/cirurgia , Humanos , Rim , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Melanoma/diagnóstico por imagem
14.
Neuropathol Appl Neurobiol ; 37(5): 441-63, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21342215

RESUMO

Varicella zoster virus (VZV) is a neurotropic herpesvirus that infects nearly all humans. Primary infection usually causes chickenpox (varicella), after which virus becomes latent in cranial nerve ganglia, dorsal root ganglia and autonomic ganglia along the entire neuraxis. Although VZV cannot be isolated from human ganglia, nucleic acid hybridization and, later, polymerase chain reaction proved that VZV is latent in ganglia. Declining VZV-specific host immunity decades after primary infection allows virus to reactivate spontaneously, resulting in shingles (zoster) characterized by pain and rash restricted to one to three dermatomes. Multiple other serious neurological and ocular disorders also result from VZV reactivation. This review summarizes the current state of knowledge of the clinical and pathological complications of neurological and ocular disease produced by VZV reactivation, molecular aspects of VZV latency, VZV virology and VZV-specific immunity, the role of apoptosis in VZV-induced cell death and the development of an animal model provided by simian varicella virus infection of monkeys.


Assuntos
Varicela/virologia , Herpes Zoster/virologia , Herpesvirus Humano 3/imunologia , Animais , Varicela/imunologia , Varicela/patologia , Herpes Zoster/imunologia , Herpes Zoster/patologia , Humanos , Neuralgia Pós-Herpética/imunologia , Neuralgia Pós-Herpética/patologia , Neuralgia Pós-Herpética/virologia
15.
Opt Express ; 19(5): 4667-72, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21369298

RESUMO

THz emission from an unbiased graphite flake after optical sub-ps pulse inter-band excitation is measured using a novel micro-machined photoconductive probe-tip. Oscillatory behavior of the measured THz near-field emission is shown to originate from electromagnetic eigenmode resonances of the laterally limited graphite flake. The excitation efficiency of the lowest order eigenmode resonances strongly dependents on optical pump location. From this data a radial symmetric charge carrier translocation at the pump location is revealed as the dominating THz surface-wave emission effect. Measurements show good agreement with numerical field simulations of the eigenmode center frequencies and the spectral response expected for THz emission through basal plane oriented radial current surge excitation.


Assuntos
Grafite/análise , Grafite/efeitos da radiação , Espectroscopia Terahertz/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Grafite/química , Luz
16.
PLoS One ; 16(4): e0249342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33793644

RESUMO

BACKGROUND: ADVanced Organ Support (ADVOS) is a novel type of extracorporeal albumin dialysis and holds promise to sustain liver function and recovery of patients with acute-on-chronic liver failure (ACLF). Previously, ADVOS was tested as continuous treatment for intensive care patients with liver failure. Data related to the applicability and safety as discontinuous treatment outside of ICU is not available. AIM: Evaluation of ADVOS as discontinuous treatment for patients with ACLF outside intensive care unit and comparison with a matched historic cohort. METHODS AND RESULTS: In this retrospective study, 26 patients with ACLF and the indication for renal replacement therapy related to HRS-AKI were included. Majority of patients were male (65%) with alcoholic cirrhosis in 88% and infections as a trigger of ACLF in 96%. Liver function was severely compromised reflected by high median MELD and CLIF-C ACLF scores of 37 (IQR 32;40) and 56.5 (IQR 51;60), respectively. Patients were treated discontinuously with ADVOS over a median time of 12 days (IQR 8.25;17) and received 8 (IQR 4.25;9.75) treatment cycles on average. No treatment related adverse events were recorded, and safety laboratory parameters remained constant during the observation time. After 16 h cumulative dialysis therapy, ADVOS significantly reduced protein-bound bilirubin (14%), creatinine (11.8%) and blood urea nitrogen (BUN, 33%). Using a matched cohort with ACLF treated with hemodialysis, ADVOS achieved a stronger decrease in bilirubin (p = 0.01), while detoxification of water-soluble catabolites' including creatinine and BUN was comparable. The 28-days mortality in the ADVOS group was 56% (14/26) and was not inferior to predicted survival (predicted median 28-days mortality was 44%, IQR 30; 59). CONCLUSION: Discontinuous ADVOS treatment was safe and effective in patients with ACLF outside intensive care and outperformed hemodialysis in reducing protein-bound metabolites.


Assuntos
Insuficiência Hepática Crônica Agudizada/terapia , Terapia de Substituição Renal , Insuficiência Hepática Crônica Agudizada/etiologia , Insuficiência Hepática Crônica Agudizada/mortalidade , Insuficiência Hepática Crônica Agudizada/patologia , Bilirrubina/sangue , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Cuidados Críticos , Feminino , Humanos , Cirrose Hepática Alcoólica/complicações , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Diálise Renal , Estudos Retrospectivos , Índice de Gravidade de Doença , Análise de Sobrevida
17.
Opt Express ; 17(20): 17412-25, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19907526

RESUMO

We have studied theoretically and experimentally the influence of a dielectric substrate on the frequency-dependent terahertz electric near-field of a small hole in a metal layer. We find that the near-field transmission spectrum and the two-dimensional field distribution of an empty hole in a thin metal layer on a substrate are almost identical to that of a hole which is also filled with the same dielectric material as the substrate. For thicker metal layers, however, the near-field spectra of filled and unfilled holes become very different. In addition, for thick metal layers, the two-dimensional field distributions are more strongly affected by the substrate, especially if we allow for an air gap between the metal and the substrate. Our results validate the -somewhat unusual- two-dimensional field distribution measured beneath a hole in a thick metal foil and highlight the effect that a substrate can have on the measurement of the near-field of an object.


Assuntos
Metais , Modelos Teóricos , Refratometria/métodos , Espectroscopia Terahertz/métodos , Simulação por Computador , Espalhamento de Radiação , Radiação Terahertz
18.
Opt Express ; 17(17): 15072-86, 2009 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-19687986

RESUMO

We present measurements of the complete terahertz (THz) electric near-field distribution, E(x), E(y) and E(z), in both the time- and frequency-domains, for subwavelength apertures and subsections of subwavelength aperture arrays. Measuring the individual components of the THz near-field with subwavelength spatial resolution, as they emerge from these structures, illustrates how the field interacts with the apertures. We observe the small but measurable y- and z-components of the electric field for both single apertures and arrays. Resonant contributions, attributed to Bloch modes, are detected and we observe the presence of a longitudinal field component, E(z), within the different array apertures, which can be attributed to a diffractive effect. These measurements illustrate in detail the individual THz field components emerging from subwavelength apertures and provide a direct measure of two important mechanisms that contribute to the net transmission of light through arrays.


Assuntos
Óptica e Fotônica , Refratometria/instrumentação , Espectroscopia Terahertz/métodos , Simulação por Computador , Desenho de Equipamento/métodos , Teste de Materiais , Refratometria/métodos , Silício/química , Ressonância de Plasmônio de Superfície/métodos
19.
J Phys Condens Matter ; 21(31): 314017, 2009 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21828578

RESUMO

We present the results of photoemission electron microscopy investigations on diindenoperylene (DIP) thin films deposited on polycrystalline gold, prepared in order to have a roughness much larger than the molecular size. Our investigations revealed the ability of the DIP molecule to form well-organized films, exhibiting a different molecular orientation with respect to the already known λ and σ phases. In locally thicker film regions, the energy of the films is minimized by a molecular arrangement that has an asymptotic tendency to the σ phase.

20.
AAPS PharmSciTech ; 10(1): 243-51, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19280348

RESUMO

The abbreviated impactor measurement concept is a potential improvement to the labor-intensive full-resolution cascade impactor methodology for inhaler aerosol aerodynamic particle size distribution (APSD) measurement by virtue of being simpler and therefore quicker to execute. At the same time, improved measurement precision should be possible by eliminating stages upon which little or no drug mass is collected. Although several designs of abbreviated impactor systems have been developed in recent years, experimental work is lacking to validate the technique with aerosols produced by currently available inhalers. In part 1 of this two-part article that focuses on aerosols produced by pressurized metered dose inhalers (pMDIs), the evaluation of two abbreviated impactor systems (Copley fast screening Andersen impactor and Trudell fast screening Andersen impactor), based on the full-resolution eight-stage Andersen nonviable cascade impactor (ACI) operating principle, is reported with a formulation producing dry particles. The purpose was to investigate the potential for non-ideal collection behavior associated with particle bounce in relation to internal losses to surfaces from which particles containing active pharmaceutical ingredient are not normally recovered. Both abbreviated impactors were found to be substantially equivalent to the full-resolution ACI in terms of extra-fine and fine particle and coarse mass fractions used as metrics to characterize the APSD of these pMDI-produced aerosols when sampled at 28.3 L/min, provided that precautions are taken to coat collection plates to minimize bounce and entrainment.


Assuntos
Teste de Materiais/instrumentação , Inaladores Dosimetrados , Medicamentos para o Sistema Respiratório/química , Tecnologia Farmacêutica/instrumentação , Administração por Inalação , Aerossóis , Desenho de Equipamento , Tamanho da Partícula , Pressão , Reprodutibilidade dos Testes , Medicamentos para o Sistema Respiratório/administração & dosagem
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