Prospective evaluation of glutamine and phospholipids levels in first degree relatives of patients with Type 1 Diabetes from a multiethnic population

BACKGROUND

A dysregulation in the metabolism of lipids may be an early marker of autoimmunity in Type 1 Diabetes (T1D). It would be of general importance to identify metabolic patterns that would predict the risk for T1D later in life. The aim of this study was to perform a prospective evaluation of glutamine and phospholipids levels in Brazilian first degree relatives (FDR) of patients with T1D in a mean interval of 5 years.

FINDINGS

Brazilian FDR (n = 30) of patients with T1D were evaluated and blood was sampled to measure the levels of glutamine and phospholipids in the fasting serum by quantitative colorimetric method. The tests were repeated after a mean interval of 5 years and compared to a control group (n = 20). The FDR presented lower levels of phospholipids than controls (p = 0.028), but not of glutamine (p = 0.075). Phospholipids levels decreased over time (p = 0.028) in FDR and were associated with Glutamic acid decarboxylase autoantibody (GADA) titers (p = 0.045), autoantibody positivity (p = 0.008) and PTPN22 polymorphisms (p = 0.014).

CONCLUSIONS

In this Brazilian multiethnic population, there was a significant decrease in phospholipids levels in FDR in patients with T1D during a 5-year prospective follow-up, as well as a significant association between these metabolite, GADA and PTPN22 polymorphisms. For Glutamine no difference was found. These findings suggest that a dysregulation in the metabolism of lipids may precede the onset of the autoimmunity in T1D.

Collagen type IV-related nephropathies in Portugal: pathogenic COL4A3 and COL4A4 mutations and clinical characterization of 25 families

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.

Collagen type IV-related nephropathies in Portugal: pathogenic COL4A5 mutations and clinical characterization of 22 families

Alport syndrome (AS) is caused by pathogenic mutations in the genes encoding α3, α4 or α5 chains of collagen IV (COL4A3/COL4A4/COL4A5), resulting in hematuria, chronic renal failure (CRF), sensorineural hearing loss (SNHL) and ocular abnormalities. Mutations in the X-linked COL4A5 gene have been identified in 85% of the families (XLAS). In this study, 22 of 60 probands (37%) of unrelated Portuguese families, with clinical diagnosis of AS and no evidence of autosomal inheritance, had pathogenic COL4A5 mutations detected by Sanger sequencing and/or multiplex-ligation probe amplification, of which 12 (57%) are novel. Males had more severe and earlier renal and extrarenal complications, but microscopic hematuria was a constant finding irrespective of gender. Nonsense and splice site mutations, as well as small and large deletions, were associated with younger age of onset of SNHL in males, and with higher risk of CRF and SNHL in females. Pathogenic COL4A3 or COL4A4 mutations were subsequently identified in more than half of the families without a pathogenic mutation in COL4A5. The lower than expected prevalence of XLAS in Portuguese families warrants the use of next-generation sequencing for simultaneous COL4A3/COL4A4/COL4A5 analysis, as first-tier approach to the genetic diagnosis of collagen type IV-related nephropathies.

Clinicopathological significance of immunoexpression of claudin-1 and claudin-7 in feline mammary carcinomas

Claudins (CLDNs) are tight junction proteins that have a role in regulating cell adhesion and polarity, paracellular permeability, proliferation and differentiation. Several immunohistochemical studies have shown reduced expression of CLDN-1 and CLDN-7 in human and canine mammary carcinomas, suggesting that these proteins may participate in mammary carcinogenesis, invasion and metastasis. The present study characterizes expression of CLDN-1 and CLDN-7 in feline mammary carcinomas (n = 52) and their metastases (n = 29). There was an inverse association between CLDN-7 expression and histological grade of tumour. Reduced expression of CLDN-7 was significantly associated with decreased tubule formation, high proliferative activity and metastasis. No significant associations were found between CLDN-1 expression and any of these features. Evaluation of expression of CLDN-7, but not CLDN-1, may therefore provide prognostic information, assisting in the diagnosis of a subgroup of aggressive feline mammary carcinomas that share some features with the recently described 'claudin-low' subgroup of human breast cancer.

Stability and reproducibility of semi-quantitative risk assessment methods within the occupational health and safety scope

BACKGROUND

In many enterprises the semi-quantitative approach turns out to be the available and most suitable technique to perform a risk assessment. Despite its advantages, we cannot disregard the existing gap in terms of validation of this type of applications.

OBJECTIVE

This paper reports a study about risk assessments' reliability, namely both inter-coder (reproducibility) and intra-coder (stability) reliability of the semi-quantitative approach.

METHODS

This study comprised 4 fundamental stages. Data collection relied on free and systematized observations and made use of video recording, documental research, analysis grids and questionnaires specifically developed for this purpose. A set of different analysts were asked to use four semi-quantitative risk assessment methods (in two different moments) to estimate and assess six risks identified in two tasks accomplished to produce Airbags. The Krippendorff's Alpha Coefficient (α K) was the agreement measure selected to evaluate both inter-coder and intra-coder consensus.

RESULTS

The preliminary results revealed a general low concordance (α K < 0.6) for both reliability evaluations. Apparently there are no relevant differences between the risk assessment results obtained by individuals with different levels of experience or expertise.

CONCLUSIONS

This study revealed that the use of the semi-quantitative approach should be done with caution.

Clinical experience with omalizumab in a Portuguese severe asthma unit

BACKGROUND

It is widely recognized that asthma control is not always possible in patients with very severe asthma despite available treatment. The aim of this study was to evaluate the efficacy of Omalizumab on asthma control as an add-on therapy in patients from the "Severe Asthma Outpatient Clinic" of Pulido Valente Hospital in Lisbon, Portugal.

METHODS

A retrospective study was conducted to assess asthma control by the ACT score and by GINA classification, frequency and severity of exacerbations, medication use and pulmonary function in patients treated with Omalizumab. Clinical information was collected from medical records from the start of treatment and at 6, 12 and 24 month follow-up.

RESULTS

26 patients started treatment with Omalizumab, all (100%) were classified by GINA with uncontrolled asthma prior to treatment. Mean ACT score was 11.5. All patients had treatment with fixed-dose ICS and LABA and 34.6% also had an anti-cholinergic inhaler. 42.3% of patients were also treated with oral glucocorticosteroids for control. Patients reported an average of 1.8 moderate and 3.1 severe exacerbations/year. Statistical differences were found at 6 month follow-up in most end-points: GINA score improved: 60.9% of patients with partially controlled asthma and only 39.1% with uncontrolled asthma (Wilcoxon 0.00); ACT score improved to 19.52 (Wilcoxon 0.00); mean FEV1 improved to 76.7% (Wilcoxon 0.025); the proportion of patients requiring oral glucocorticosteroid therapy reduced to 17.4% (Wilcoxon 0.014); and the number of moderate and severe exacerbations also decreased to 1.04 and 1.83 respectively (Wilcoxon 0.007; Wilcoxon 0.002 respectively).

CONCLUSIONS

The current analysis shows evidence that omalizumab is successful in improving asthma control as an add-on therapy GINA step 5 treatment.

Reduced expression of claudin-2 is associated with high histological grade and metastasis of feline mammary carcinomas

Claudins (CLDNs) are a family of tight junction (TJ) proteins that play an important role in maintaining cell polarity, in controlling paracellular ion flux and in regulating cell proliferation and differentiation. There is a growing body of evidence that associates changes in CLDN expression with the development of human breast cancer. In the present study CLDN-2 expression was examined immunohistochemically in samples of normal feline mammary tissue (n = 5) and mammary carcinomas (n = 52), including metastatic lesions (n = 29). Seventy-seven percent of carcinomas showed reduced CLDN-2 expression compared with that observed in normal mammary gland. Reduced expression of CLDN-2 was significantly associated with a high histological grade of carcinoma (P = 0.011), with 88.6% of grade II/III carcinomas showing decreased expression. Furthermore, CLDN-2 down-regulation was significantly associated with metastatic disease (P = 0.0027), with 93.1% of cases with signs of metastasis showing decreased expression of this protein. CLDN-2 may constitute a molecular marker for identification of a subgroup of feline mammary carcinomas characterized by high histological grade and the development of metastasis.

Consumo e deposição de ácidos graxos no longissimus de novilhos Nelore suplementados em pastagens

Objetivou-se estudar a correlação entre consumo e deposição de ácidos graxos no músculo Longissimus de novilhos nelore suplementados em pastagens. O trabalho de campo foi implantado numa área de 52 ha, formada de Brachiaria brizantha. Foram utilizados 40 novilhos da raça Nelore com peso inicial médio de 373,7 ± 14,9 kg e 26 meses de idade, distribuídos em quatro tratamentos:Controle= T00 (fornecimento apenas de sal mineral), T03= fornecimento de 0,3% concentrado em função do peso vivo; T06= fornecimento de 0,6 % concentrado em função do peso vivo; T09= fornecimento de 0,9 % concentrado em função do peso vivo. Amostras dos concentrados e da forragem foram coletadas para análise da composição de ácidos graxos. O período experimental foi de 98 dias. Após este período, os animais foram abatidos. Os resultados foram analisados por Correlação Linear de Pearson e teste t. Constatou-se que existem correlações entre os ácidos graxos consumidos e depositados no músculo.

Contribution of oxidative metabolism to cocaine-induced liver and kidney damage

Cocaine is a potent psychoactive illicit substance and its abuse represents a major health burden worldwide. The pharmacodynamics and toxicity of cocaine have been extensively documented, and are generally associated to its affinity towards neurotransmitters transporters and several receptors. However, drug-related formation of reactive compounds, as is the case of pro-oxidant reactive species, and interaction at molecular level is still an understudied matter. The involvement of oxidative stress (OS) in cocaine-induced toxicity has been reported in both human and animal models, in several organs and systems, including heart, liver, kidney, and central nervous system (CNS). Cytochrome P450 (CYP450)-mediated cocaine metabolism yields the reactive pro-oxidant compound norcocaine (NCOC) and further oxidative metabolites. Special emphasis should be given to the stable radical norcocaine nitroxide (NCOC-NO·), which plays a key role in cocaine-induced hepatotoxicity, either by entering a futile redox cycle with an N-oxidative metabolite, or by being further oxidized to a highly reactive ion. In fact, cocaine-induced generation of reactive oxygen species (ROS) and consequent OS has been postulated based on the reactivity of cocaine N-oxidative metabolites. Depletion of cellular antioxidant defenses and impairment of mitochondrial respiration have also been considered important causes of ROS production, and subsequent cell death mediated by cocaine. The present review provides a thorough description of the current knowledge on cocaine oxidative metabolism and its role on drug-induced liver and kidney damage.