147 resultados para diffuse light


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Times Cited: 0 References: 0 Citation MapAbstract : Background: Chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard treatment for relapsed DLBCL. No study has compared salvage therapies and evaluated maintenance post ASCT.Methods: DLBCL CD 20+ in first relapse or pts refractory after first therapy were randomized between R ICE (rituximab, ifosfamide, etoposide, carboplatinum) or R DHAP (rituximab dexamethasone cytarabine cisplatinum). Responding patients received BEAM and ASCT then randomized between observation or maintenance with rituximab every 2 m for 1 yr (Gisselbrecht J Clin Oncol; 2010).Results: Analysis was made on 477 pts (R ICE: 243 pts; R DHAP: 234 pts): 255 relapses >12m, 213 refractory/early relapses; 306 pts had prior rituximab; secondary(s) IPI 0-1: 281 pts; s IPI 2-3:181pts. There was no difference in response rate between R ICE 63.6% and R DHAP 64.3%. There was no difference between R ICE and R DHAP at 4 yrs for EFS (26% vs 37% p=0.2) and OS (43% vs 51%, p=0.3). Factors affecting 4 yrs EFS, PFS and OS were: prior treatment with rituximab; early relapse< 12 m; s IPI 2-3. ASCT was performed in 255 pts and 242 randomized for maintenance: 122 pts rituximab (R), 120 pts observation (O). Distribution between R/O arms were respectively: median age 54 /53 yrs, Male 76/83; female 46/37; secondary IPI 0-1: 84/81; sIPI 2-3: 36/36. 89/76 relapses >12m., 33/41 refractory/early relapses. Median follow up was 44 m with 111 events. 4 yrs EFS was 52.8 % (CI 46-59) with 63% (CI 56-69) OS. There was no difference in EFS, PFS and OS between R and O arms. In multivariate analysis, sIPI2-3 significantly affected EFS, PFS, OS (p=0.0004). Women (83pts) had a better 4 yrs EFS 63% than male (159pts) 37% (p=0.01). The difference was only in the R arm (p=0.004). Gender was an independent prognostic factor in the R arm. Toxicity was mild with 12% SAE versus 4% for R /O respectively.Conclusions: There was no difference between R ICE and R DHAP and between post ASCT maintenance with R or O. Women did significantly better after ASCT with rituximab. Early relapses to upfront rituximab-based chemotherapy have a poor prognosis.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Higher plants possess multiple members of the phytochrome family of red, far-red light sensors to modulate plant growth and development according to competition from neighbors. The phytochrome family is composed of the light-labile phyA and several light-stable members (phyB-phyE in Arabidopsis). phyA accumulates to high levels in etiolated seedlings and is essential for young seedling establishment under a dense canopy. In photosynthetically active seedlings high levels of phyA counteract the shade avoidance response. phyA levels are maintained low in light-grown plants by a combination of light-dependent repression of PHYA transcription and light-induced proteasome-mediated degradation of the activated photoreceptor. Light-activated phyA is transported from the cytoplasm where it resides in darkness to the nucleus where it is needed for most phytochrome-induced responses. Here we show that phyA is degraded by a proteasome-dependent mechanism both in the cytoplasm and the nucleus. However, phyA degradation is significantly slower in the cytoplasm than in the nucleus. In the nucleus phyA is degraded in a proteasome-dependent mechanism even in its inactive Pr (red light absorbing) form, preventing the accumulation of high levels of nuclear phyA in darkness. Thus, light-induced degradation of phyA is in part controlled by a light-regulated import into the nucleus where the turnover is faster. Although most phyA responses require nuclear phyA it might be useful to maintain phyA in the cytoplasm in its inactive form to allow accumulation of high levels of the light sensor in etiolated seedlings.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction: In a prior study, we demonstrated that ACVBP + consolidation was superior to 3 cycles of CHOP + radiotherapy in young patients (pts) with localized aggressive lymphoma (Reyes F et al. N Engl J Med 2005;352:1197). This randomized trial compared in these pts ACVBP vs. ACVBP + a short course of rituximab (R-ACVBP).Methods: untreated pts between 18 and 65y with stage I/II DLBCL and no adverse prognostic factors according to the aa-IPI were eligible. ACVBP consisted of 3 induction cycles given every 2 weeks: doxorubicin (75 mg/m2) day 1, cyclophosphamide (1.2g/m2) day 1, vindesine (2 mg/m2) day 1 and 5, bleomycin (10 mg) day 1 and 5, prednisone (60 mg/m2) day 1 to 5 followed by consolidation with metothrexate, ifosfamide, VP-16 and cytarabine. R-ACVBP consisted of the same regimen combined with 4 doses of rituximab (375 mg/m2) on day 1, 15, 29 and 43. Primary objective was EFS.Results: From 01/04 to 03/08, 223 pts were randomized, 113 in ACVBP and 110 in R-ACVBP arm. Characteristics were: median age 49y (18-65), stage I 63%, extranodal involvement 45%, bulky disease 4%. CR was 94% in ACVBP and 97% in ACVBP arm (ns). With a median follow-up of 43 months, the 3-y EFS was 82% (95% CI, 73% to 88%) in ACVBP and 93% (95% CI, 87% to 97%) in R-ACVBP group (P=0.0487). The 3-y PFS was 83% (95% CI, 74% to 89%) and 95% (95% CI, 89% to 98%) respectively (P=0.0205). OS did not significantly differ with a 3-y estimates of 97% (95% CI, 90% to 99%) for ACVBP and 98% (95% CI, 92% to 100%) for R-ACVBP (P=0.686). In multivariate analysis, a longer PFS was associated with R-ACVBP arm (P=0.0302) and lower b2-m level (P=0.0164). The same proportion of pts (27%) experienced at least 1 SAE in both groups. There were 4 deaths in each arm, with 1 treatment-related death in R-ACVBP (pneumocystis jiroveci pneumonia).Conclusion: the addition of only 4 doses of rituximab to ACVBP significantly improves EFS and PFS in younger pts with low-risk localized DLBCL.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Main developmental programs are highly conserved among species of the animal kingdom. Improper execution of these programs often leads to progression of various diseases and disorders. Here we focused on Drosophila wing tissue morphogenesis, a fairly complex developmental program, one of the steps of which - apposition of the dorsal and ventral wing sheets during metamorphosis - is mediated by integrins. Disruption of this apposition leads to wing blistering which serves as an easily screenable phenotype for components regulating this process. By means of RNAi-silencing technique and the blister phenotype as readout, we identify numerous novel proteins potentially involved in wing sheet adhesion. Remarkably, our results reveal not only participants of the integrin-mediated machinery, but also components of other cellular processes, e.g. cell cycle, RNA splicing, and vesicular trafficking. With the use of bioinformatics tools, these data are assembled into a large blisterome network. Analysis of human orthologues of the Drosophila blisterome components shows that many disease-related genes may contribute to cell adhesion implementation, providing hints on possible mechanisms of these human pathologies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: To determine the usefulness of computed tomography (CT), magnetic resonance imaging (MRI), and Doppler ultrasonography (US) in providing specific images of gouty tophi. METHODS: Four male patients with chronic gout with tophi affecting the knee joints (three cases) or the olecranon processes of the elbows (one case) were assessed. Crystallographic analyses of the synovial fluid or tissue aspirates of the areas of interest were made with polarising light microscopy, alizarin red staining, and x ray diffraction. CT was performed with a GE scanner, MR imaging was obtained with a 1.5 T Magneton (Siemens), and ultrasonography with colour Doppler was carried out by standard technique. RESULTS: Crystallographic analyses showed monosodium urate (MSU) crystals in the specimens of the four patients; hydroxyapatite and calcium pyrophosphate dihydrate (CPPD) crystals were not found. A diffuse soft tissue thickening was seen on plain radiographs but no calcifications or ossifications of the tophi. CT disclosed lesions containing round and oval opacities, with a mean density of about 160 Hounsfield units (HU). With MRI, lesions were of low to intermediate signal intensity on T(1) and T(2) weighting. After contrast injection in two cases, enhancement of the tophus was seen in one. Colour Doppler US showed the tophi to be hypoechogenic with peripheral increase of the blood flow in three cases. CONCLUSION: The MR and colour Doppler US images showed the tophi as masses surrounded by a hypervascular area, which cannot be considered as specific for gout. But on CT images, masses of about 160 HU density were clearly seen, which correspond to MSU crystal deposits.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study aimed at exploring adolescents' perceptions of unwanted sexual experiences (USE) in order to set up definitions, categories, and boundaries on the continuum between consensual and non-consensual sex. METHODS: We conducted a qualitative thematic analysis of four focus group discussions gathering a total of 29 male and female adolescents aged 16-20 years. RESULTS: Analysis of participants' discourse revealed three main characteristics that define USE, namely, regret, as most situations discussed were said to be acceptable or not in terms of whether there were regrets after the fact; misperception of sexual intent; and lack of communication between partners. CONCLUSIONS: Our findings revealed that health professionals should be aware of the subtle aspects identifying USE when screening for situations that can have adverse psychological consequences. Where prevention is concerned, it appears important to address these aspects of USE in sex education classes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Autofluorescence bronchoscopy (AFB) is a highly sensitive tool for the detection of early bronchial cancers. However, its specificity remains limited due to primarily false positive results induced by hyperplasia, metaplasia and inflammation. We have investigated the potential of blue-violet backscattered light to eliminate false positive results during AFB in a clinical pilot study. METHODS: The diagnostic autofluorescence endoscopy (DAFE) system was equipped with a variable band pass filter in the imaging detection path. The backscattering properties of normal and abnormal bronchial mucosae were assessed by computing the contrast between the two tissue types for blue-violet wavelengths ranging between 410 and 490 nm in 12 patients undergoing routine DAFE examination. In a second study including 6 patients we used a variable long pass (LP) filter to determine the spectral design of the emission filter dedicated to the detection of this blue-violet light with the DAFE system. RESULTS: (Pre-)neoplastic mucosa showed a clear wavelength dependence of the backscattering properties of blue-violet light while the reflectivity of normal, metaplastic and hyperplastic autofluorescence positive mucosa was wavelength independent. CONCLUSIONS: Our results showed that the detection of blue-violet light has the potential to reduce the number of false positive results in AFB. In addition we determined the spectral design of the emission filter dedicated to the detection of this blue-violet light with the DAFE system.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Ambient light conditions trigger both developmental transitions, such as the induction of flowering, and a suite of adaptive responses, exemplified by the shade-avoidance syndrome. These responses are initiated by three families of photoreceptors that are conserved in all higher plants: the phototropins, cryptochromes and phytochromes (phyA--phyE, cry1--cry3, phot1 and phot2 in Arabidopsis). Molecular genetic studies performed mainly in Arabidopsis indicate that photon capture by these light sensors usually initiates rapid changes in the gene expression profile, leading to plant adaptation to their environment. Interestingly, numerous transcription factors are early targets of light regulation, both at the transcriptional and post-transcriptional levels.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The interaction of a parasite and a host cell is a complex process, which involves several steps: (1) attachment to the plasma membrane, (2) entry inside the host cell, and (3) hijacking of the metabolism of the host. In biochemical experiments, only an event averaged over the whole cell population can be analyzed. The power of microscopy, however, is to investigate individual events in individual cells. Therefore, parasitologists frequently perform experiments with fluorescence microscopy using different dyes to label structures of the parasite or the host cell. Though the resolution of light microscopy has greatly improved, it is not sufficient to reveal interactions at the ultrastructural level. Furthermore, only specifically labeled structures can be seen and related to each other. Here, we want to demonstrate the additional value of electron microscopy in this area of research. Investigation of the different steps of parasite-host cell interaction by electron microscopy, however, is often hampered by the fact that there are only a few cells infected, and therefore it is difficult to find enough cells to study. A solution is to profit from low magnification, hence large overview, and specific location of the players by fluorescence labels in a light microscope with the high power resolution and structural information provided by an electron microscope, in short by correlative light and electron microscopy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: to describe a case of probable bilateral diffuse uveal melanocytic proliferation (BDUMP) with scleral involvement, free from systemic malignancies and cataract. Methods: fifty months of follow up with recurrent complete ophthalmological examinations, including fundus photography, fluorescein/indocyanine green angiography (FA) and optical coherence tomography (OCT). Investigations also included an electroretinography (ERG) and histological examination of scleral biopsy. Extraocular malignancies were repeatedly searched. Results: the patient was a 61 year-old Italian man with chronic hepatitis type C. At first visit his best corrected visual acuity (BCVA) was 20/32 in OS and 20/25 in OD. Funduscopy showed multiple patch-shaped pigmented alterations involving macular region and mid retinal periphery. FA showed corresponding areas of late-phase hyperfluorescent pinpoints (figure 1a, OS) and intemediate-phase hypocyanescence (figure 1b, OS), with subtle serous neurosensory retinal detachment confirmed by OCT. Photopic and scotopic ERG tested normal. Systemic prednisone was administered for one month without any improvement. After ten months round pigmentary lesions appeared also in superior scleral surface of both eyes. Biopsy allowed to disclose slightly pigmented spindle cells. BCVA worsened for further 10 months, with enlargement of FA alteration areas but lenses still clear. After 30 months spontaneous coalescence and atrophy of retinal lesions started, paralleled by progressive visual recovery. At the end of our follow up BCVA was 20/25 in OU while scleral pigmentary lesions remained unchanged. Conclusions: we report the case of a patient with main features of BDUMP and some unusual findings. Although not all classical diagnostic criteria were fulfilled, the presence of scleral pigmented lesions and spontaneous visual recovery may enlarge clinical spectrum of the disease.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: To investigate how prior-to-injury and usual alcohol consumption relate to time of injury. Patients and methods: The associations between injury time of day and day of week and prior-to-injury (labeled as "acute") alcohol intake and hazardous usual alcohol consumption (considered from the point of view of both heavy episodic drinking [HED] and risky volumes of consumption) are assessed using interview data from a randomized sample of 486 injured patients treated in a Swiss emergency department (ED; Lausanne University Hospital). Results: Acute consumption was associated with both injury time of day and day of week, HED with day of week only, and risky volume with none. Conclusions: Acute consumption and HED, but not risky volume of consumption, show specific time distributions for injuries. These findings highlight the potential importance of considering the time dimension of an injury when providing emergency care and have additional implications for interventions aimed at influencing the alcohol consumption of injured patients presenting to the ED.