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1.
Nature ; 444(7115): 97-101, 2006 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-17080091

RESUMO

Ustilago maydis is a ubiquitous pathogen of maize and a well-established model organism for the study of plant-microbe interactions. This basidiomycete fungus does not use aggressive virulence strategies to kill its host. U. maydis belongs to the group of biotrophic parasites (the smuts) that depend on living tissue for proliferation and development. Here we report the genome sequence for a member of this economically important group of biotrophic fungi. The 20.5-million-base U. maydis genome assembly contains 6,902 predicted protein-encoding genes and lacks pathogenicity signatures found in the genomes of aggressive pathogenic fungi, for example a battery of cell-wall-degrading enzymes. However, we detected unexpected genomic features responsible for the pathogenicity of this organism. Specifically, we found 12 clusters of genes encoding small secreted proteins with unknown function. A significant fraction of these genes exists in small gene families. Expression analysis showed that most of the genes contained in these clusters are regulated together and induced in infected tissue. Deletion of individual clusters altered the virulence of U. maydis in five cases, ranging from a complete lack of symptoms to hypervirulence. Despite years of research into the mechanism of pathogenicity in U. maydis, no 'true' virulence factors had been previously identified. Thus, the discovery of the secreted protein gene clusters and the functional demonstration of their decisive role in the infection process illuminate previously unknown mechanisms of pathogenicity operating in biotrophic fungi. Genomic analysis is, similarly, likely to open up new avenues for the discovery of virulence determinants in other pathogens.


Assuntos
Genoma Fúngico/genética , Ustilago/genética , Ustilago/patogenicidade , Zea mays/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Genes Fúngicos/genética , Genômica , Família Multigênica/genética , Ustilago/crescimento & desenvolvimento , Virulência/genética
2.
Schmerz ; 25(6): 663-7, 2011 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-21997184

RESUMO

BACKGROUND: Only limited data and experience with patient-controlled analgesia (PCA) in outpatients for palliative home care, related to organization, effectiveness and costs are available. PATIENTS AND METHODS: In our retrospective study we analyzed the effectiveness, care intensity and pain reduction of 108 palliative cancer pain patients with PCA, included in a palliative home care system. RESULTS: After equivalent conversion of the opioid doses from oral/transcutaneus to parenteral administration a dose increase was necessary in 12.9% of the patients. The pain therapy was effective until death for an average of 38.9 days (median 21 days). During 3,889 days of PCA therapy there were 76 unscheduled visits based on technical problems. CONCLUSION: In cases of cancer pain patients with failed oral or transcutaneous opioid medication, sufficient pain reduction can be achieved with parenteral drug administration by PCA. Domestic PCA requires a lot of human and financial resources, with trained nursing services and regular house visits by physicians experienced in palliative medicine but this method is sufficient and safe to use.


Assuntos
Analgesia Controlada pelo Paciente , Analgésicos Opioides/administração & dosagem , Serviços de Assistência Domiciliar/organização & administração , Neoplasias/fisiopatologia , Dor/tratamento farmacológico , Cuidados Paliativos/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgesia Controlada pelo Paciente/economia , Analgesia Controlada pelo Paciente/instrumentação , Análise Custo-Benefício , Relação Dose-Resposta a Droga , Substituição de Medicamentos , Falha de Equipamento/estatística & dados numéricos , Feminino , Serviços de Assistência Domiciliar/economia , Humanos , Assistência de Longa Duração/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Neoplasias/economia , Neoplasias/mortalidade , Medição da Dor/efeitos dos fármacos , Cuidados Paliativos/economia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
3.
Vet Parasitol ; 147(3-4): 258-64, 2007 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-17544583

RESUMO

A randomized, blinded, controlled multicentre field trial study was conducted to evaluate the efficacy and safety of imidacloprid 10%/moxidectin 2.5% spot-on solution and fenbendazole in treating dogs naturally infected with Angiostrongylus vasorum. Dogs were randomly treated either with a single dose of 0.1 ml/kg bodyweight of imidacloprid 10%/moxidectin 2.5% spot-on solution or with 25 mg/kg bodyweight fenbendazole per os for 20 days. The study period was 42 days with dogs being examined on days 0, 7 and 42. The primary efficacy parameter was the presence of L1 larvae in faecal samples evaluated by a Baermann test from three consecutive days. Thoracic radiographs performed on each visit were being taken as a paraclinical parameter to support the results of the Baermann test. Twenty-seven dogs in the imidacloprid/moxidectin group and 23 dogs in the fenbendazole group completed the study according to protocol. The efficacies of the two treatment protocols were 85.2% (imidacloprid/moxidectin) and 91.3% (fenbendazole) with no significant difference between treatment groups. On radiographic evaluation pulmonary parenchyma showed similar improvement in each group. No serious adverse effects to treatment were recorded: most of the minor adverse effects were gastrointestinal such as diarrhea (nine dogs), vomitus (eight dogs) and salivation (three dogs). In general, these adverse effects were of short duration (1-2 days) within the first few days after treatment start and required little or no treatment. This prospective study demonstrates that both treatment protocols used are efficacious under field conditions, that treatment of mildly to moderately infected dogs with either of these protocols is safe and yields an excellent prognosis for recovering from the infection.


Assuntos
Angiostrongylus/isolamento & purificação , Anti-Helmínticos/administração & dosagem , Doenças do Cão/tratamento farmacológico , Fenbendazol/uso terapêutico , Imidazóis/uso terapêutico , Nitrocompostos/uso terapêutico , Infecções por Strongylida/veterinária , Administração Tópica , Animais , Anti-Helmínticos/uso terapêutico , Cães , Quimioterapia Combinada , Feminino , Fenbendazol/administração & dosagem , Imidazóis/administração & dosagem , Macrolídeos/administração & dosagem , Macrolídeos/uso terapêutico , Masculino , Neonicotinoides , Nitrocompostos/administração & dosagem , Infecções por Strongylida/tratamento farmacológico
4.
Georgian Med News ; (144): 49-52, 2007 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-17473335

RESUMO

The accuracy of breath alcohol measurements in intubated patients with assisted ventilation was evaluated. The breath alcohol concentration was measured in 24 patients undergoing percutaneous alcohol injection therapy for hepatocellular carcinoma with Alcotest 7410 med, from Dräger, Germany. The blood ethanol concentrations (BACs) were determined in each blood serum applying the German forensic criteria standard, namely, two alcohol dehydrogenase (ADH) and two gas chromatography (GC) measurements. The blood alcohol concentrations were between 0.07 and 1.51 per thousand in the central venous samples and 0.02-1.66 per thousand in the arterial samples. An excellent correlation between both the venous and arterial blood alcohol concentrations (r2=0.94), as well as between the breath alcohol concentrations and the venous (r2=0.84) or arterial alcohol concentration (r2=0.89), p<0.01 for both parameters was revealed. Determination of breath alcohol concentration using the Alcotest in intubated patients is reliable and reflects the blood alcohol values.


Assuntos
Intoxicação Alcoólica/diagnóstico , Testes Respiratórios , Carcinoma Hepatocelular/terapia , Depressores do Sistema Nervoso Central/sangue , Depressores do Sistema Nervoso Central/uso terapêutico , Etanol/sangue , Etanol/uso terapêutico , Neoplasias Hepáticas/terapia , Respiração Artificial , Administração Cutânea , Idoso , Depressores do Sistema Nervoso Central/administração & dosagem , Etanol/administração & dosagem , Feminino , Humanos , Instilação de Medicamentos , Masculino
5.
Dalton Trans ; 46(26): 8359-8362, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28650036

RESUMO

Liquid phase exfoliation (LPE) of layered compounds towards few- or monolayers has been established as one of the prime methods in the growing field of 2D material research. Here, we present first steps towards an effective LPE of bismuth(iii) iodide, a semiconductor with potential as a photovoltaic absorber material. We highlight guidelines in the choice of exfoliating solvent, which differ significantly from those used with transition metal dichalcogenides or graphene. We also present first evidence of successful few-layer formation from spectroscopic, electron microscopy and electron diffraction investigations.

6.
Aust Vet J ; 84(1-2): 17-21, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16498829

RESUMO

The study was undertaken to evaluate and compare the efficacy of an imidacloprid (10% w/v)/moxidectin (2.5% w/v) combination (Advocate Bayer HealthCare, Animal Health) with that of selamectin for the treatment of Sarcoptes scabiei on dogs. Thirty naturally infested dogs, of which one was later withdrawn because of distemper, were allocated to two equal groups and individually housed. The dogs in each group were treated twice, four weeks apart, with either the combination product (0.1 mL/kg body weight) or with selamectin (0.05 mL/kg body weight) administered topically. Skin scrapings were made every 14 days over a period of 50 to 64 days after the first treatment to quantify mite numbers. Clinical signs and the extent of sarcoptic lesions were assessed on each dog when skin scrapings were made. Efficacy was based on the presence or absence of mites, supported by clinical signs associated with canine sarcoptic mange. From Day 22 and onwards no Sarcoptes mites were found in the skin scrapings of any of the treated dogs. Treatment with the imidacloprid/moxidectin formulation or with selamectin was highly effective against Sarcoptes scabiei and resulted in an almost complete resolution of clinical signs within 50 to 64 days after the initial treatment.


Assuntos
Doenças do Cão/tratamento farmacológico , Imidazóis/uso terapêutico , Inseticidas/uso terapêutico , Sarcoptes scabiei/efeitos dos fármacos , Escabiose/veterinária , Administração Tópica , Animais , Cães , Quimioterapia Combinada , Feminino , Ivermectina/análogos & derivados , Ivermectina/uso terapêutico , Macrolídeos/uso terapêutico , Masculino , Neonicotinoides , Nitrocompostos , Escabiose/tratamento farmacológico , Resultado do Tratamento
7.
Parasitol Res ; 97 Suppl 1: S81-S88, 2005 10.
Artigo em Inglês | MEDLINE | ID: mdl-16228280

RESUMO

Efficacy and safety of treatment with imidacloprid 10%+moxidectin 2.5% spot-on (Advocate, Advantage multi; Bayer AG, Leverkusen, Germany) were tested in dogs naturally infested with Sarcoptes scabiei or Otodectes cynotis in a multi-centre, controlled, randomized, blinded field study conducted in France, Germany, Albania and the UK. The study was performed according to a non-inferiority design to demonstrate that the efficacy of imidacloprid/moxidectin spot-on was not inferior to that of a control product containing selamectin (Stronghold spot-on; Pfizer). All Sarcoptes-infested dogs were topically treated twice (days 0 and 28) with the dosage recommended by the respective manufacturer (27 dogs with imidacloprid/moxidectin, 26 with selamectin). All Otodectes-infested dogs were treated on day 0 (35 dogs with imidacloprid/moxidectin, 34 with selamectin), and only those still positive on day 28 received a second treatment. Parasitological cure rate in Sarcoptes-infested dogs was 100% for both treatments, while parasitological cures rates in the Otodectes-infested dogs at day 28 and day 56 were 68.6 and 85.7% with imidacloprid/moxidectin, and 64.7 and 88.2% with Stronghold. Non-inferiority of Advocate was confirmed statistically. Clinical assessment of skin lesion scores at day 56 showed that with either product >96% of the dogs treated against sarcoptic mange were improved or cured, the difference between the groups being non-significant. On the basis of a final clinical assessment of lesion scores, 80% of the dogs treated with imidacloprid/moxidectin against otoacariosis and 85.3% of those treated with selamectin were rated cured or improved. Only three mild, possibly drug-related adverse reactions were observed among alI treated animals (two in the imidacloprid/moxidectin group, one in the selamectin group). It is concluded that imidacloprid/moxidectin spot-on is an effective and safe treatment for sarcoptic mange and otoacariosis in the dog.


Assuntos
Doenças do Cão/tratamento farmacológico , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Infestações por Ácaros/veterinária , Nitrocompostos/administração & dosagem , Nitrocompostos/uso terapêutico , Administração Tópica , Animais , Cães , Quimioterapia Combinada , Otopatias/parasitologia , Otopatias/veterinária , Feminino , Inseticidas/administração & dosagem , Inseticidas/uso terapêutico , Ivermectina/análogos & derivados , Ivermectina/uso terapêutico , Macrolídeos/administração & dosagem , Macrolídeos/uso terapêutico , Masculino , Infestações por Ácaros/tratamento farmacológico , Neonicotinoides
8.
Parasitol Res ; 97 Suppl 1: S89-S96, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16228281

RESUMO

Efficacy and safety of the test product imidacloprid 10%+moxidectin 2.5% spot on (Advocate, Advantage multi) in the treatment of canine generalized demodicosis were evaluated in a multi-centre, controlled, randomized, blinded field study in Albania, France, and Germany. The study was conducted according to a non-inferiority design to demonstrate that the efficacy of the test product is not inferior to that of a control product containing milbemycin oxime (Interceptor, tablets for oral application). Of the 72 dogs enrolled, all of which expressed clinical signs of generalized demodicosis, 63 completed the study. Of these, 30 dogs were treated 2-4 times, at 4-week intervals, with the test product at the recommended dose of at least 0.1 ml/kg body weight. Thirty-three dogs were treated daily for two to four periods of 4 weeks with the control product according to label instructions (0.5-1 or 1-2 mg/kg body weight). Presence of mites in deep skin scrapings and clinical improvement were assessed 3-6 times at each inspection at 4-week intervals. Treatment was discontinued in dogs negative for mites on two subsequent examinations 4 weeks apart or at the last examination on day 84. At the end of the trial, dogs in both groups showed a similar clinical improvement. No Demodex mites were detected in 26 of 30 dogs treated with imidacloprid/moxidectin and in 29 of 33 dogs treated with milbemycin oxime. Statistical evaluation confirmed that the efficacy of the test product in the treatment of generalized canine demodicosis was not inferior to that of milbemycin oxime.


Assuntos
Doenças do Cão/tratamento farmacológico , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Infestações por Ácaros/veterinária , Nitrocompostos/administração & dosagem , Nitrocompostos/uso terapêutico , Administração Tópica , Animais , Doenças do Cão/epidemiologia , Cães , Quimioterapia Combinada , Feminino , França/epidemiologia , Alemanha/epidemiologia , Inseticidas/administração & dosagem , Inseticidas/uso terapêutico , Macrolídeos/administração & dosagem , Macrolídeos/uso terapêutico , Masculino , Infestações por Ácaros/tratamento farmacológico , Infestações por Ácaros/epidemiologia , Neonicotinoides
9.
Neuroscience ; 309: 68-83, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26012492

RESUMO

The field of autoimmune encephalitides associated with antibodies targeting cell-surface antigens is rapidly expanding and new antibodies are discovered frequently. Typical clinical presentations include cognitive deficits, psychiatric symptoms, movement disorders and seizures and the majority of patients respond well to immunotherapy. Pathophysiological mechanisms and clinical features are increasingly recognized and indicate hippocampal dysfunction in most of these syndromes. Here, we review the neuroimaging characteristics of autoimmune encephalitides, including N-methyl-d-aspartate (NMDA) receptor, leucine-rich glioma inactivated 1 (LGI1), contactin-associated protein-like 2 (CASPR2) encephalitis as well as more recently discovered and less frequent forms such as dipeptidyl-peptidase-like protein 6 (DPPX) or glycine receptor encephalitis. We summarize findings of routine magnetic resonance imaging (MRI) investigations as well as (18)F-fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET) and single photon emission tomography (SPECT) imaging and relate these observations to clinical features and disease outcome. We furthermore review results of advanced imaging analyses such as diffusion tensor imaging, volumetric analyses and resting-state functional MRI. Finally, we discuss contributions of these neuroimaging observations to the understanding of the pathophysiology of autoimmune encephalitides.


Assuntos
Encefalite/diagnóstico por imagem , Encefalite/patologia , Doença de Hashimoto/diagnóstico por imagem , Doença de Hashimoto/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Neuroimagem/métodos , Animais , Encefalite/fisiopatologia , Doença de Hashimoto/fisiopatologia , Hipocampo/fisiopatologia , Humanos , Cintilografia
10.
Med Phys ; 42(2): 623-36, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25652480

RESUMO

PURPOSE: The authors are developing a system for calibrated breast density measurements using full field digital mammography (FFDM). Breast tissue equivalent (BTE) phantom images are used to establish baseline (BL) calibration curves at time zero. For a given FFDM unit, the full BL dataset is comprised of approximately 160 phantom images, acquired prior to calibrating prospective patient mammograms. BL curves are monitored serially to ensure they produce accurate calibration and require updating when calibration accuracy degrades beyond an acceptable tolerance, rather than acquiring full BL datasets repeatedly. BL updating is a special case of generalizing calibration datasets across FFDM units, referred to as cross-calibration. Serial monitoring, BL updating, and cross-calibration techniques were developed and evaluated. METHODS: BL curves were established for three Hologic Selenia FFDM units at time zero. In addition, one set of serial phantom images, comprised of equal proportions of adipose and fibroglandular BTE materials (50/50 compositions) of a fixed height, was acquired biweekly and monitored with the cumulative sum (Cusum) technique. These 50/50 composition images were used to update the BL curves when the calibration accuracy degraded beyond a preset tolerance of ±4 standardized units. A second set of serial images, comprised of a wide-range of BTE compositions, was acquired biweekly to evaluate serial monitoring, BL updating, and cross-calibration techniques. RESULTS: Calibration accuracy can degrade serially and is a function of acquisition technique and phantom height. The authors demonstrated that all heights could be monitored simultaneously while acquiring images of a 50/50 phantom with a fixed height for each acquisition technique biweekly, translating into approximately 16 image acquisitions biweekly per FFDM unit. The same serial images are sufficient for serial monitoring, BL updating, and cross-calibration. Serial calibration accuracy was maintained within ±4 standardized unit variation from the ideal when applying BL updating. BL updating is a special case of cross-calibration; the BL dataset of unit 1 can be converted to the BL dataset for another similar unit (i.e., unit 2) at any given time point using the 16 serial monitoring 50/50 phantom images of unit 2 (or vice versa) acquired near this time point while maintaining the ±4 standardized unit tolerance. CONCLUSIONS: A methodology for monitoring and maintaining serial calibration accuracy for breast density measurements was evaluated. Calibration datasets for a given unit can be translated forward in time with minimal phantom imaging effort. Similarly, cross-calibration is a method for generalizing calibration datasets across similar units without additional phantom imaging. This methodology will require further evaluation with mammograms for complete validation.


Assuntos
Mama/citologia , Mamografia/métodos , Intensificação de Imagem Radiográfica/métodos , Calibragem , Humanos , Imagens de Fantasmas , Controle de Qualidade
11.
FEBS Lett ; 446(1): 15-7, 1999 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-10100605

RESUMO

It is known that low intensity magnetic fields increase superoxide anion production during the respiratory burst of rat peritoneal neutrophils in vitro. We investigated whether the high intensity magnetic fields (1.5 T) during magnetic resonance imaging can influence the human neutrophil function under in vivo conditions. Blood samples were obtained from 12 patients immediately before and after magnetic resonance imaging (mean time 27.6(+/-11.4 min)). The induced respiratory burst was investigated by the intracellular oxidative transformation of dihydrorhodamine 123 to the fluorescent dye rhodamine 123 via flow cytometry. The respiratory burst was induced either with phorbol 12-myristate 13-acetate, Escherichia coli, N-formyl-methionyl-leucylphenylalanine or priming with tumor necrosis factor followed by FMLP stimulation. There was no significant difference between the respiratory burst before and after magnetic resonance imaging, irrespective of the stimulating agent. Short time exposure to a high intensity magnetic field during magnetic resonance imaging seems not to influence the production of radical species in living neutrophils.


Assuntos
Imageamento por Ressonância Magnética/efeitos adversos , Neutrófilos/efeitos da radiação , Explosão Respiratória/efeitos da radiação , Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Ratos
12.
Int J Radiat Oncol Biol Phys ; 37(3): 629-37, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9112462

RESUMO

PURPOSE: The present "sandwich" preoperative and postoperative chemotherapy and radiation study was undertaken to evaluate the impact of treatment intensity on the local control and survival in tethered or fixed rectal adenocarcinoma (T3, 4 NX M0). METHODS AND MATERIALS: Between 1990 and 1992, 27 patients were treated with this sandwich protocol. Preoperative therapy consisted of 4 weeks of concurrent radiation (40 Gy) and chemotherapy (mitomycin C on day 1, 5-fluorouracil infusion and leucovorin on days 1-4 and days 15-18, respectively), and one cycle of bolus 5-fluorouracil and leucovorin chemotherapy. After surgery, they received 2 additional weeks of radiation (18 Gy) and 4 days of similar chemotherapy. The outcome was compared to another 54 patients who were treated with our previous preoperative chemoradiation protocol (mitomycin C, 5-fluorouracil infusion and 40 Gy of pelvic RT). RESULTS: The complete resectability rate was improved from 91% in the preoperative protocol to 100% in the sandwich protocol, and the pathologic complete response rate (T0 N0 M0) was increased from 4 to 15%. There was no local recurrence in the sandwich protocol. The 4-year local failure rate was 23 vs. 0% (p = 0.005). The 4-year distant failure rate was 47 vs. 28% (p = 0.079). The 2-year and 4-year survival were 63 and 41% for the preoperative protocol, vs. 92 and 72% for the sandwich protocol, respectively (p = 0.014). There were more treatment-related Grade 2 diarrhea, but not Grade 3/4 diarrhea in the sandwich protocol. Two patients (7%) in the sandwich protocol developed late gastrointestinal complications. CONCLUSIONS: More intensive radiation and chemotherapy appeared to improve the resectability, local control, and survival in tethered and fixed rectal cancers. There was a moderate but acceptable increase in the bowel morbidity.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Antídotos/administração & dosagem , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Metástase Neoplásica , Radioterapia/efeitos adversos , Dosagem Radioterapêutica , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia
13.
Int J Radiat Oncol Biol Phys ; 48(3): 843-56, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11020583

RESUMO

PURPOSE: To study the impact of preoperative radiation dose escalation and postoperative adjuvant chemotherapy on the outcome of tethered and fixed rectal carcinoma. METHODS AND MATERIALS: We have treated 156 patients with 3 consecutive preoperative chemoradiation protocols with escalating treatment intensity. Schedule 1 consisted of 40 Gy radiation with concurrent 5-fluorouracil (5-FU) infusion and mitomycin C. Schedule 2 used a sandwich design with preoperative (40 Gy) and postoperative (18 Gy) radiation with concomitant 5-FU infusion, leucovorin, and mitomycin C. In schedule 3, the preoperative radiation dose was increased to 50 Gy and adjuvant 5-FU/leucovorin chemotherapy was added following surgery. There were 54, 27, and 75 patients treated in schedules 1, 2, and 3, respectively. RESULTS: The resectability was 91% for schedule 1 and 100% for both schedules 2 and 3. A dose-response relationship was observed between the radiation dose and the tumor downstaging and local control. The pathological complete response (T0N0M0) rates for schedules 1, 2, and 3 were 4%, 15%, and 25%, respectively. The respective rates of tumor downstaging were 41%, 33%, and 68%, respectively. The 5-year local relapse-free rates were 67% for schedule 1 (40 Gy), 96% for schedule 2 (58 Gy), and 92% for schedule 3 (50 Gy) (p = 0.0011). The addition of postoperative chemotherapy appeared to improve both the survival and the relapse-free survival. The 5-year survival was increased from 52% to 84% (p = 0.0004) and the 5-year progression-free survival was improved from 48% to 74% (p = 0.0008). CONCLUSION: Preoperative 5-FU infusion, leucovorin, mitomycin C, and 50-Gy pelvic radiation, followed by postoperative bolus 5-FU/leucovorin chemotherapy, appeared to be an effective treatment for tethered/fixed rectal cancers. However, its therapeutic efficacy could only be validated in randomized studies.


Assuntos
Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Relação Dose-Resposta à Radiação , Feminino , Fluoruracila/administração & dosagem , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Estadiamento de Neoplasias , Cuidados Pré-Operatórios , Dosagem Radioterapêutica , Neoplasias Retais/patologia
14.
Intensive Care Med ; 25(6): 612-5, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10416914

RESUMO

OBJECTIVE: Superoxide production by polymorphonuclear neutrophils (PMNs) under cyclosporin A (CsA) therapy following kidney transplantation is impaired. We investigated if the respiratory burst of PMNs is similarly depressed in patients undergoing CsA treatment following orthotopic liver transplantation (OLTx). Additionally, the in vitro influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) on the superoxide anion production was examined during the respiratory burst. PATIENTS: 10 patients after OLTx and 10 healthy blood donors (control group). MEASUREMENTS AND RESULTS: PMNs were stimulated with bacteria (Escherichia coli) or a combination of tumour necrosis factor alpha (TNFalpha) and N-formyl-methionyl-leucyl-phenylalanine (FMLP). The respiratory burst was measured by oxidation of non-fluorescent dihydrorhodamine to the fluorescent rhodamine by means of flow cytometry. No differences in respiratory bursts from OLTx patients compared to those from healthy blood donors could be seen. Under TNFalpha/FMLP stimulation, the respiratory burst was significantly increased after in vitro incubation with GM-CSF (500 U ml(-1)) in patients following OLTx (from 58.2 to 74.5 %) as well as in the control group (from 47.4 to 61.9%). CONCLUSIONS: Our results demonstrate that superoxide production is not impaired under CsA treatment following OLTx. The respiratory burst of these patients' PMNs can even be augmented by GM-CSF in vitro.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Transplante de Fígado/imunologia , Neutrófilos/fisiologia , Explosão Respiratória/efeitos dos fármacos , Ciclosporina/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Técnicas In Vitro , Explosão Respiratória/fisiologia , Superóxidos/metabolismo
16.
Med Phys ; 27(12): 2644-51, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11190946

RESUMO

A statistical methodology is presented based on a chi-square probability analysis that allows the automated discrimination of radiolucent tissue (fat) from radiographic densities (fibroglandular tissue) in digitized mammograms. The method is based on earlier work developed at this facility that shows mammograms may be considered as evolving from a linear filtering operation where a random input field is passed through a 1/f filtering process. The filtering process is reversible which allows the solution of the input field with knowledge obtained from the raw image (the output). The input field solution is analogous to a prewhitening technique or deconvolution. This field contains all the information of the raw image in a much simplified format that can be approximated and analyzed with parametric methods. In the work presented here evidence indicates that there are two random events occurring in the input field with differing variances: (1) one relating to fat tissue with the smaller variance, and (2) the second relating to all other tissue with the larger variance. A statistical comparison of the variances is made by scanning the image with a small search window. A relaxation method allows for making a reliable estimate of the smaller variance which is considered as the global reference. If a local variance deviates significantly from the reference variance, based on chi-square analysis, it is labeled as nonfat; otherwise it is labeled as fat. This statistical test procedure results in a region by region continuous labeling of fat and nonfat tissue across the image. In the work presented here, the emphasis is on the methodology development with supporting preliminary results that are very encouraging. It is widely accepted that mammographic density is a breast cancer risk factor. An important application of this work is to incorporate density-based risk analysis into the ongoing statistical-based detection work developed at this facility. Additional applications include risk analysis dependent on either percentages or total amounts of fat or dense tissue. This work may be considered as the initial step in introducing many of the known breast cancer risk factors into the actual image data analysis.


Assuntos
Mama/patologia , Mama/fisiologia , Mamografia/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Estatísticos
17.
Med Phys ; 26(11): 2254-65, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10587206

RESUMO

We show that digitized mammograms can be considered as evolving from a simple process. A given image results from passing a random input field through a linear filtering operation, where the filter transfer function has a self-similar characteristic. By estimating the functional form of the filter and solving the corresponding filtering equation, the analysis shows that the input field gray value distribution and spectral content can be approximated with parametric methods. The work gives a simple explanation for the variegated image appearance and multimodal character of the gray value distribution common to mammograms. Using the image analysis as a guide, a simulated mammogram is generated that has many statistical characteristics of real mammograms. Additional benefits may follow from understanding the functional form of the filter in conjunction with the input field characteristics that include the approximate parametric description of mammograms, showing the distinction between homogeneously dense and nondense images, and the development of mass analysis methods.


Assuntos
Mamografia/métodos , Modelos Estatísticos , Intensificação de Imagem Radiográfica/métodos , Neoplasias da Mama/diagnóstico por imagem , Interpretação Estatística de Dados , Feminino , Fractais , Humanos , Distribuição Normal
18.
Med Phys ; 25(9): 1655-66, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9775370

RESUMO

Current MRI nonuniformity correction techniques are reviewed and investigated. Many approaches are used to remedy this artifact, but it is not clear which method is the most appropriate in a given situation, as the applications have been with different MRI coils and different clinical applications. In this work four widely used nonuniformity correction techniques are investigated in order to assess the effect on tumor response measurements (change in tumor volume over time): a phantom correction method, an image smoothing technique, homomorphic filtering, and surface fitting approach. Six brain tumor cases with baseline and follow-up MRIs after treatment with varying degrees of difficulty of segmentation were analyzed without and with each of the nonuniformity corrections. Different methods give significantly different correction images, indicating that rf nonuniformity correction is not yet well understood. No improvement in tumor segmentation or in tumor growth/shrinkage assessment was achieved using any of the evaluated corrections.


Assuntos
Neoplasias Encefálicas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Fenômenos Biofísicos , Biofísica , Estudos de Avaliação como Assunto , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Imagens de Fantasmas
19.
Resuscitation ; 43(2): 147-50, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10694175

RESUMO

Management of the difficult airway requires an appropriate approach based on personal clinical experiences. For every physician involved in rescue and emergency medicine, it is important to know the difficult airway algorithm and be familiar with alternative techniques of managing the difficult airway. We report a case of tracheal injury caused by multiple attempts at intubating the trachea. Based on current knowledge, apart from surgical equipment for cricothyroidotomy the laryngeal mask airway (LMA) and the Combitube (ETC) should be available on any ambulance vehicle staffed by an emergency physician. In future, blind intubation through the intubating laryngeal mask airway (ILMA) could offer a new opportunity.


Assuntos
Reanimação Cardiopulmonar/efeitos adversos , Intubação Intratraqueal/efeitos adversos , Traqueia/lesões , Serviços Médicos de Emergência , Humanos , Masculino , Pessoa de Meia-Idade
20.
IEEE Trans Med Imaging ; 16(5): 503-15, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9368106

RESUMO

A multiresolution statistical method for identifying clinically normal tissue in digitized mammograms is used to construct an algorithm for separating normal regions from potentially abnormal regions; that is, small regions that may contain isolated calcifications. This is the initial phase of the development of a general method for the automatic recognition of normal mammograms. The first step is to decompose the image with a wavelet expansion that yields a sum of independent images, each containing different levels of image detail. When calcifications are present, there is strong empirical evidence that only some of the image components are necessary for the purpose of detecting a deviation from normal. The underlying statistic for each of the selected expansion components can be modeled with a simple parametric probability distribution function. This function serves as an instrument for the development of a statistical test that allows for the recognition of normal tissue regions. The distribution function depends on only one parameter, and this parameter itself has an underlying statistical distribution. The values of this parameter define a summary statistic that can be used to set detection error rates. Once the summary statistic is determined, spatial filters that are matched to resolution are applied independently to each selected expansion image. Regions of the image that correlate with the normal statistical model are discarded and regions in disagreement (suspicious areas) are flagged. These results are combined to produce a detection output image consisting only of suspicious areas. This type of detection output is amenable to further processing that may ultimately lead to a fully automated algorithm for the identification of normal mammograms.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Mamografia , Algoritmos , Mama/anatomia & histologia , Doenças Mamárias/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Simulação por Computador , Diagnóstico por Computador , Feminino , Humanos , Mamografia/estatística & dados numéricos , Modelos Biológicos , Modelos Estatísticos , Reconhecimento Automatizado de Padrão , Probabilidade
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