Applying an adaptive watershed to the tissue cell quantification during T-cell migration and embryonic development

Cell and particle quantification is one of the frequently used techniques in biology and clinical study. Variations of cell/particle population and/or protein expression level can provide information on many biological processes. In this chapter, we propose an image-based automatic quantification approach that can be applied to images from both fluorescence and electron microscopy. The algorithm uses local maxima to identify labelling targets and uses watershed segmentation to define their boundaries. The method is able to provide information on size, intensity centroids and average intensity within the labelling partitions. Further developed from this method, we demonstrated its applications in four different research projects, including recruitment enumeration of circulating T cell in non-lymphoid tissues, cell clustering in the early development of the chick embryo, gold particle localization and clustering in electron microscopy, and registration/co-localization of transcription factors in neural tube development of early chick embryo. The advantages and limitations of the method are also discussed.

Mortality and functional impairment after hip fracture - a prospective study in a Portuguese population

OBJECTIVES

Osteoporotic hip fractures (HF) are a major cause of morbidity and mortality with increasing familial, social and economic repercussions. The objectives of this paper were to evaluate the status vitae at 6 and 12 months of a cohort of patients with an osteoporotic HF and the risk factors for 12-month mortality as well as to evaluate the functional outcome and the overall health perception of these patients.

PATIENTS AND METHODS

We conducted a 12-month follow-up evaluation of a cohort of 184 patients older than 65 years admitted to our centre with a non-pathological osteoporotic HF from January 1st to December 31st 2007. Baseline data collection was performed in the first 72 hours after admission and, 12 months later, a second evaluation was conducted, by telephone in order to ascertain their status vitae and functional status. The magnitude of sex--specific, age-adjusted associations between potential prognostic factors and mortality was estimated using hazard ratios (HR) and respective 95% confidence intervals (95%CI), calculated using Cox's proportional hazards model.

RESULTS

It was possible to ascertain the status vitae in 164 (89.1%) patients. Overall 12-months mortality was 26.8% (48.3% in males and 22.2% in females). Mortality was higher in patients that became bedridden, were unable to walk again, were admitted to a hospital during the follow-up for any cause and who became dependent in their daily living activities. After discharge, physical therapy and ability to walk again were associated with a lower risk of death. Most of the patients reported a decline of their overall health-related quality of life. More than 75% of patients became totally dependent after HF.

CONCLUSION

This study reinforces the HF poor outcome. Twelve-month mortality rates were similar to the estimates obtained in other studies, although the 6-month's mortality was higher. Physical deterioration and loss of independence in activities of daily living were evident in this study and constituted major factors for low self-esteem and deterioration of quality of life. Our findings may constitute an evidence for action in this particular population, with an active search for means to improve the outcome of HF in these patients.

Association of IL23R and ERAP1 genes with ankylosing spondylitis in a Portuguese population

OBJECTIVE

Association between ankylosing spondylitis (AS) and two genes, ERAP1 and IL23R, has recently been reported in North American and British populations. The population attributable risk fraction for ERAP1 in this study was 25%, and for IL23R, 9%. Confirmation of these findings to ERAP1 in other ethnic groups has not yet been demonstrated. We sought to test the association between single nucleotide polymorphisms (SNPs) in these genes and susceptibility to AS among a Portuguese population. We also investigated the role of these genes in clinical manifestations of AS, including age of symptom onset, the Bath Ankylosing Spondylitis Disease Activity, Metrology and Functional Indices, and the modified Stoke Ankylosing Spondylitis Spinal Score.

METHODS

The study was conducted on 358 AS cases and 285 ethnically matched Portuguese healthy controls. AS was defined according to the modified New York Criteria. Genotyping of IL23R and ERAP1 allelic variants was carried out with TaqMan allelic discrimination assays. Association analysis was performed using the Cochrane-Armitage and linear regression tests of genotypes as implemented in PLINK for dichotomous and quantitative variables respectively. A meta-analysis for Portuguese and previously published Spanish IL23R data was performed using the StatsDirect Statistical tools, by fixed and random effects models.

RESULTS

A total of 14 nsSNPs markers (8 for IL23R, 5 for ERAP1, 1 for LN-PEP) were analysed. Three markers (2 for IL23R and 1 for ERAP1) showed significant single-locus disease associations, confirming that the association of these genes with AS in the Portuguese population. The strongest associated SNP in IL23R was rs1004819 (OR=1.4, p=0.0049), and in ERAP1 was rs30187 (OR=1.26, p=0.035). The population attributable risk fractions in the Portuguese population for these SNPs are 11% and 9.7% respectively. No association was seen with any SNP in LN-PEP, which flanks ERAP1 and was associated with AS in the British population. No association was seen with clinical manifestations of AS.

CONCLUSION

These results show that IL23R and ERAP1 genes are also associated with susceptibility to AS in the Portuguese population, and that they contribute a significant proportion of the population risk for this disease.

A Case of Early Dementia in a Schizoaffective Disorder Patient

Establishing a differential diagnosis in psychiatry may be very laboring. The authors aim to illustrate diagnostic complexity and its therapeutic implications, through the presentation and discussion of a presumable dementia clinical picture. We present the case of a fifty six-year old woman, attending our outpatient clinics since her twenties with the diagnosis of schizoaffective disorder. On April of 2007 the patient was admitted to a fifteen-day hospitalization due to psychotic symptoms, which remitted with therapeutic doses of risperidone and ansiolytics. One week after being discharged the patient was readmitted to the hospital due to an abrupt onset of a clinical picture characterized by behavioral changes, motor agitation and repetitive behaviors, refusal to eat, depressive mood, mystical delusions, hallucinatory activity, loss of insight, and severe impairment in occupational and social functioning. Although several clinical trials of antipsychotics, antidepressants and mood stabilizers were tried, along with electroconvulsive therapy, her general clinical state has remained unchanged for the fifteen months of hospitalization. Blood and urine examinations, tumoral markers, infectious and immunological study, lumbar puncture, neuroimaging, EEG and brain biopsy were performed, without conclusive results. We consider that the presumptive diagnosis is a Frontotemporal Dementia (FTD). Due to this entity's distinct neuropsychiatric manifestations, its diagnosis can be challenging. This presentation also emphasizes the importance of a holistic analyzes of clinical situations and of a multidisciplinary approach.

Impact of impellers on the axisymmetric magnetic mode in the VKS2 dynamo experiment

In the von Kármán Sodium 2 (VKS2) successful dynamo experiment of September 2006, the observed magnetic field showed a strong axisymmetric component, implying that nonaxisymmetric components of the flow field were acting. By modeling the induction effect of the spiraling flow between the blades of the impellers in a kinematic dynamo code, we find that the axisymmetric magnetic mode is excited. The control parameters are the magnetic Reynolds number of the mean flow, the coefficient measuring the induction effect alpha, and the type of boundary conditions. We show that using realistic values of alpha, the observed critical magnetic Reynolds number, Rm;{c} approximately 32, can be reached easily with ferromagnetic boundary conditions. We conjecture that the dynamo action achieved in this experiment may not be related to the turbulence in the bulk of the flow, but rather to the alpha effect induced by the impellers.

Effect of Fusarium verticillioides extract on specific antibody production against Paracoccidioides brasiliensis

The aim of this study was to evaluate the effect of partially purified Fusarium verticillioides fumonisins (FB) on the specific humoral response in mice infected with Paracoccidioides brasiliensis (Pb), the agent of paracoccidioidomycosis (PCM). Four groups of male Swiss mice were used (total 44 mice): infected (Pb), treated (FB), infected and treated (Pb/FB) and uninfected and untreated (PBS). Groups Pb and Pb/FB were inoculated i.v. with 1x105 Pb yeast cells (strain Pb18) and, after 28 days, groups FB and Pb/FB were inoculated (s.c.) with partially purified FB from F. verticillioides (5x2.25 mg FB/kg body weight). After 7 days, the plasma levels of total IgG and anti-gp43 IgG (specific antibody) were analysed by immunoenzyme assay (ELISA). The total IgG level was higher in groups Pb, FB and Pb/FB than in PBS (P<0.05) and the anti-gp43 IgG level was raised in groups Pb and Pb/FB, but a significant result was obtained only in Pb/FB, relative to the other groups (P<0.05). In conclusion, FB or other components of F. verticillioides extracts significantly increase the specific antibody response in male Swiss mice infected with Pb.

Erythematous candidosis in patients with complete dentures and HIV+/AIDS

This investigation was designed to evaluate the frequency of erythematous candidosis (EC) and Candida species, proteinase and phospholipase exoenzyme production, and to compare clinical features in patients with complete dentures and HIV+/Acquired Immunodeficiency Disease Syndrome (AIDS). Fifty-one patients were selected from a total of 285 with EC: denture wearers (n = 30) and HIV+/AIDS (n = 21). The yeast prevalence and the production of exoenzymes, such as proteinase and phospholipase by Candida species were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) electrophoresis. The frequency of Candida albicans was significantly higher (P < 0.05) in both groups although other yeast species (Candida glabrata, Candida krusei, Candida parapsilosis, Candida guilliermondi and Candida tropicalis) were also found. Candida albicans showed greater levels of proteinase production in the denture wearers, when compared with the HIV+/AIDS group. There was no difference between groups with regard to phospholipase production. The protein bands presented similar molecular weights, showing the presence of proteinases in both groups. It could be concluded that the clinical manifestation of EC may be related to its proteinase production capacity. Combination therapies using proteinase inhibitors play an important role in inhibiting exoenzyme production by Candida species, mainly C. albicans.

In neuroblastic tumours, Schwann cells do not harbour the genetic alterations of neuroblasts but may nevertheless share the same clonal origin

Neuroblastic tumours are composed of variable proportions of neuroblasts and Schwann cells. Whether both components share a common neoplastic origin is highly debated and discrepant results have been reported about the presence of tumour-related genetic alterations in Schwann cells. We have used X-methylation analysis and array-CGH to investigate contiguous Schwannian and neuroblastic areas in tumours with a nodular pattern. A skewed X inactivation was observed in four out of five stromal components. Interestingly, in these four cases, the X-inactivation profiles of the neuroblastic components were identical to the matched stromal areas. However, whereas all neuroblastic areas displayed chromosomal imbalances, no alteration was found in any Schwann cell components. Similarly, no alteration was observed in a series of 19 tumours with a single stroma-rich component, which occasionally exhibited a skewed X-inactivation pattern (3/17 informative tumours). Altogether, this indicates that most stroma-rich tumours display a polyclonal proliferation and that Schwann cells do not derive from neuroblasts. However, in tumours with both stroma-rich and -poor components, our results suggest that cells from both areas share a common progenitor.

Emergence in Brazil of methicillin-resistant Staphylococcus aureus isolates carrying SCCmecIV that are related genetically to the USA800 clone

An increasing incidence of nosocomial infections caused by non-multiresistant methicillin-resistant Staphylococcus aureus (nMMRSA) has been reported worldwide. The present study genotyped nMMRSA isolates obtained from hospitals in two cities in Brazil. The hospital isolates displayed pulsed-field gel electrophoresis (PFGE) patterns that were similar to those of the USA100 (ST5-SCCmecII) and USA 800 (ST5-SCCmecIV) strains, which are related to the New York/Japan and paediatric clones, respectively. Carriage of SCCmecIV and the classification by multilocus sequence typing (MLST) of a representative of this PFGE pattern in clonal complex 5 (CC5) confirmed the genetic relationship of the Brazilian isolates with USA800. The USA800-related Brazilian isolates were responsible for severe nosocomial infections in compromised adults and elderly patients in Brazil. A higher growth rate, an ability to form biofilm on inert polystyrene surfaces and the presence of the egc locus may have contributed, at least in part, to the fitness of these organisms as global nosocomial pathogens.

Nanobiotechnological approach to engineered biomaterial design: the example of elastin-like polymers

Today, the development of advanced biomaterials is still lacking an appropriate tailored engineering approach. Most of the biomaterials currently used have their origin in materials developed for other technological applications. This lack of adequate biomaterial design is probably due to the peculiar environment where those materials must operate. On the one hand, this environment is dominated by the immune rejection system. On the other hand, the functionality of natural biomolecules is based on complex topological physical-chemical function distributions at the nanometer level. This review presents arguments concerning the role of biotechnology and nanotechnology in the future development of new advanced biomaterials and the potential of these biomaterials as a way to achieve highly biofunctional and truly biocompatible biomaterials for hot areas, such as regenerative medicine and controlled release. Recombinant protein-polymers will be presented as an example of candidates for this new paradigm in biomaterial design and production.

Chromosomal CGH identifies patients with a higher risk of relapse in neuroblastoma without MYCN amplification

Whereas neuroblastoma (NB) with MYCN amplification presents a poor prognosis, no single marker allows to reliably predict outcome in tumours without MYCN amplification. We report here an extensive analysis of 147 NB samples at diagnosis, without MYCN amplification, by chromosomal comparative genomic hybridisation (CGH), providing a comprehensive overview of their genomic imbalances. Comparative genomic hybridisation profiles showed gains or losses of entire chromosomes (type 1) in 71 cases, whereas partial chromosome gains or losses (type 2), including gain involving 17q were observed in 68 cases. Atypical profiles were present in eight cases. A type 1 profile was observed more frequently in localised disease (P<0.0001), and in patients of less than 12 months at diagnosis (P<0.0001). A type 2 genomic profile was associated with a higher risk of relapse in the overall population (log-rank test; P<0.0001), but also in the subgroup of patients with localised disease (log-rank test, P=0.007). In multivariate analysis, the genomic profile was the strongest independent prognostic factor. In conclusion, the genomic profile is of prognostic impact in patients without MYCN amplification, making it a help in the management of low-stage NB. Further studies using higher-resolution CGH are needed to better characterise atypical genomic alterations.