Cytokeratins in primary cutaneous amyloidosis

The expression of keratins was investigated immunohistochemically on formalin-fixed and snap-frozen primary cutaneous amyloidosis tissue with a panel of monospecific and polyspecific antikeratin antibodies which recognized keratins K1, K5, K6, K7, K8, K10, K14, K16, K17, K18, and K19. Amyloid deposits in frozen section of seven cases of macular amyloidosis and lichen amyloidosus always reacted with antibodies LP34 (labeling K5, K6 and K18) MNF (labeling K5, K6, K8, K10, K17 and K18) and RCK 102 (labeling K5 and K8); frozen section in one case each of the seven cases also reacted with antibodies LL001 (labeling K14), Lp1K (labeling K7 and K17), and LP2K (labeling K19), LP1K (labelling K7 and K17), and LP2K (labelling K19), In formalin fixed section of 13 cases of macular amyloidosis and lichen amyloidosus amyloid deposits were labeled with LP34 in three section LL020 ()labelling keratins K5 and K6) in one section and LP2K in two section. In nodular primary cutaneous amyloidosis amyloid deposits were not labeled with any antikeratin antibodies. These data confirm that amyloid in macular amyloidosis and lichen amyloidosus contains keratin epitopes, and suggests derivation of the fibrillar component from keratin intermediate filaments Several different keratins appear to undergo conversion to amyloid, LP34, MNF 116 and RCK 102 antibodies, which have in common the labelling of keratin K5, may be useful in the diagnosis of macular and popular amyloidosis with frozen tissue section.     

"I will do it if it will help others:" motivations among patients taking part in qualitative studies in palliative care

The aim of this study was to explore patients' and carers' preferences and expectations regarding their contribution to research in palliative care through the use of qualitative interviews. Data were collected in the context of two studies exploring the experiences of care of palliative care patients and carers. Both studies recorded the recruitment process, numbers of patients or carers accepting and declining, and the circumstances of interviews. Participants were asked about their motivation to participate in research. The data were analyzed by labeling patients' reflections on their motivations for participating in these studies and identifying themes. Analysis of the recruitment process revealed differential patterns in decline and acceptance of interviews by patients with different conditions and across settings. Among cancer patients, 21/51 declined; the proportion with other conditions that declined was small, and was 0/10 for patients with motor neuron disease. Motivation to participate in the studies was related to (1) altruism, (2) gratitude and concerns about care, (3) the need to have somebody to talk to, and (4) the need for information or access to services. Palliative care patients and carers were capable of deciding whether to participate in interviews and negotiating how they wanted this to happen. This strengthens the argument for patients' autonomy in deciding whether to participate in research. Patients and carers have different motivations for participation, reflecting the heterogeneity of the palliative care population. This suggests a need for ethics committees to reconsider their views and widen their perspectives on the involvement of palliative care patients and carers in research.     

Cluster headache: To scan or not to scan

By definition, cluster headache (CH) is not caused by underlying structural pathology. However, patients with CH or CH-like syndromes and an associated structural lesion have been described. In many cases it is difficult to establish a causal relation between the headache syndrome and the lesion. We reviewed the literature for symptomatic CH or CH-like cases in which causality was very likely, and we found that even typical CH with a typical episodic time pattern and a response to typical CH treatment can be caused by underlying structural pathology such as a pituitary tumor. Based on this small retrospective series of case reports, it is impossible to give advice about neuroimaging. If neuroimaging is considered, MRI (not CT) is the investigation of choice.     

Physiological noise modelling for spinal functional magnetic resonance imaging studies

Spinal cord functional imaging allows assessment of activity in primary synaptic connections made by sensory neurons relaying information about the state of the body. However, reported human data based on gradient-echo techniques have been largely inconsistent, with no clear patterns of activation emerging. One reason for this variability is the influence of physiological noise, which is typically not corrected for. By acquiring single-slice resting data from the spinal cord with a conventional gradient-echo EPI pulse sequence at TR=200 ms (critically sampled) and TR=3 s (under-sampled), we have characterised various sources of physiological noise. In 8 healthy subjects, the presence of physiologically dependent signal was explored using probabilistic independent component analysis (PICA). Based on the insights provided by PICA, we defined a new physiological noise model (PNM) based on retrospective image correction (RETROICOR), which uses independent physiological measurements taken from the subject to model sources of noise. Statistical significance of individual components included in the PNM was assessed by F-tests, which demonstrated that the optimal PNM included cardiac, respiratory, interaction and low-frequency regressors. In a group of 10 healthy subjects, activation data were acquired from the cervical spinal region (T1 to C5) during painful thermal stimulation of the right and left hands. The improvement obtained when using a PNM in estimating spinal cord activation was reflected in a reduction of false-positive activation (active voxels in the CSF space surrounding the cord), when compared to conventional GLM modelling without a PNM.     

Therapeutic vaccination halts disease progression in BALB-neuT mice: the amplitude of elicited immune response is predictive of vaccine efficacy

The aim of this study was to evaluate the efficacy of genetic vaccination with rat ErbB2 antigen in a therapeutic setting for the BALB-neuT mouse model of mammary carcinoma and to establish immunological correlates with vaccine efficacy. To define an early therapeutic setting we performed imaging studies of mouse mammary glands with a high-frequency ultrasound system that allowed the diagnosis of tumor lesions before they become palpable, starting from week 13 after mouse births. An intensive immunization protocol of vaccination was implemented at this stage, consisting of four weekly DNA injections with electroporation followed by two injections of adenovirus carrying the codon usage-optimized cDNA encoding the extracellular-transmembrane domain of rat ErbB2. Immunological parameters were monitored in each individual mouse by analyzing peripheral blood leukocytes. The appearance of the first palpable tumor in vaccinated mice was delayed and there was a statistically significant time gap before additional masses developed, indicating disease stabilization. As a result of the immunization, antibodies and CD8(+) T cells to rat ErbB2 were detected and the amplitude of elicited responses correlated with the efficacy of vaccination. Moreover, the vaccination regimen specifically halted the rise in circulating myeloid suppressor cells (MSCs). All three parameters, that is, CD8(+) T cells, antibodies to rat ErbB2, and circulating MSCs, measured at the end of vaccination could be used as predictive biomarkers for future tumor development. This study emphasizes the potential of genetic vaccines for the therapeutic treatment of malignancies and suggests possible predictive biomarkers to be further validated in the clinic for the follow-up of vaccinated cancer patients.     

Complementary information from multi-exponential T2 relaxation and diffusion tensor imaging reveals differences between multiple sclerosis lesions

While conventional magnetic resonance imaging (MRI) has long been used to study multiple sclerosis (MS), more sensitive and specific approaches to studying both MS lesions and normal appearing white matter (NAWM) are needed to gain a better understanding of the pathogenesis of the disease. Two MRI techniques thought to offer insight regarding myelin and axonal integrity are T(2) relaxation and diffusion tensor imaging (DTI). In this study, metrics obtained from T(2) relaxation (specifically myelin water content (MWC) and long-T(2) fraction) and DTI experiments (in particular the fractional anisotropy, mean diffusivity , parallel diffusivity lambda(||), and perpendicular diffusivity lambda(perpendicular)) were compared for 19 MS patients within both lesion and contralateral NAWM with the goal of better understanding how each of the measures are affected by pathology. In particular, it was successfully determined that the detection of a long-T(2) signal within an MS lesion is indicative of a different underlying pathology than is present in lesions without long-T(2) signal. All of the diffusion metrics were significantly different in lesions with a long-T(2) signal than in those without. While no significant correlations were found between MWC and , lambda(||) or lambda(perpendicular) in NAWM (R(2)=0.02-0.04, p>0.07), and only weak correlations were found in lesions without long-T(2) signal (R(2)=0.05-0.14, p<0.04), strong correlations were observed in lesions exhibiting long-T(2) signal (R(2)=0.54-0.61, p<0.0001).