A novel Chilean salmon fish backbone-based nanoHydroxyApatite functional biomaterial for potential use in bone tissue engineering

Introduction

Given the ensuing increase in bone and periodontal diseases and defects, de novo bone repair and/or regeneration strategies are constantly undergoing-development alongside advances in orthopedic, oro-dental and cranio-maxillo-facial technologies and improvements in bio-/nano-materials. Indeed, there is a remarkably growing need for new oro-dental functional biomaterials that can help recreate soft and hard tissues and restore function and aesthetics of teeth/ dentition and surrounding tissues. In bone tissue engineering, HydroxyApatite minerals (HAp), the most stable CaP/Calcium Phosphate bioceramic and a widely-used material as a bone graft substitute, have been extensively studied for regenerative medicine and dentistry applications, including clinical use. Yet, limitations and challenges owing principally to its bio-mechanical strength, exist and therefore, research and innovation efforts continue to pursue enhancing its bio-effects, particularly at the nano-scale.

Methods

Herein, we report on the physico-chemical properties of a novel nanoHydroxyApatite material obtained from the backbone of Salmon fish (patent-pending); an abundant and promising yet under-explored alternative HAp source. Briefly, our nanoS-HAp obtained via a modified and innovative alkaline hydrolysis-calcination process was characterized by X-ray diffraction, electron microscopy, spectroscopy, and a cell viability assay.

Results and Discussion

When compared to control HAp (synthetic, human, bovine or porcine), our nanoS-HAp demonstrated attractive characteristics, a promising biomaterial candidate for use in bone tissue engineering, and beyond.

Training the Armed Forces personnel in COVID-19 contact tracing: a Portuguese case study

Background

Local contact tracing teams needed to be reinforced in preparation for a peak in Covid-19 cases. The Portuguese Armed Forces showed availability and their members initiated a formal training facilitated by the Public Health Unit (PHU) of Amadora. Health systems must be prepared to respond to all threats, as the COVID-19 pandemic showed us the need for quick task shifting and the training of non-experts’ workers.

Objectives

The aim of the project was to develop contact tracing skills by non-health professionals, in the context of the COVID-19 pandemic. The training program was held online, with a total duration of 48 hours, distributed by the topics described: introduction to health and epidemiology concepts, the national guidelines, and the information systems (13h). We privileged demonstrative and participatory training methods, followed by continuous supervision of each contact tracing survey and constant feedback (35h). Learning support materials were sent out to assist the trainees, including written and video support.

Results

More than 200 personnel - sailors, soldiers and airmen - were trained. Each Lisbon and Tagus Valley area PHU was reinforced with a team of military professionals in order to support the contact tracing process, with an increase in the number of surveys completed. We highlight as positive aspects: increased number of contact tracing surveys carried out; growth of inter-institutional partnerships; freeing up of specialized PHU resources to other important tasks. As for negative aspects we focus on the complexity in health communication, the limited time for training, and the lack of specific health knowledge of the trainees.

Conclusions

This pandemic revealed the Portuguese need for a transdisciplinary approach in the provision of care, specially at a Public Health level. Training programs like these highlight the vital role of reshaping and reorganizing the healthcare workforce answering Public Health necessities.

Key messages

• Training programs for non-health workers must be prepared to reinforce health systems when necessary. The reinforcement of contact tracing teams by the Portuguese Armed Forces was a great example.

• A transdisciplinary approach in the provision of care was essential during the COVID-19 pandemic. Specific training of non-health workers can be planned in time to respond to health threats.

Psychiatric disorders during acute hospital treatment of COVID-19 - a case series

Introduction

Coronavirus disease (COVID-19) has been associated with the development mental and behavioural symptoms and psychiatric disorders. This association is stronger in severe cases of the disease and in those needing inpatient treatment, particularly in intensive care units (ICU).

Objectives

To determine the incidence of psychiatric disorders in a Portuguese hospital-based sample of patients with COVID-19. To describe relevant demographic and clinical data.

Methods

We reviewed all COVID-19 inpatients assessed by liaison psychiatry at our hospital between April and September 2020. Patients admitted due to a psychiatric disorder were excluded from the analysis. We reviewed medical records and retrieved relevant clinical data. ICD-10 was used to classify diagnoses.

Results

We identified 36 cases with a mean age of 62.64 years-old (SD 19.23). The most common disorder was delirium, which occurred in 41.7% of our sample (15 patients), followed by adjustment disorder (22.2%, n=8), and depressive episode (16.7%, n=8). Most patients had no personal (61.1%, n=22) nor family (75%, n=27) history of a psychiatric disorder. Mean length of admission was 36.89 days (SD 28.91). Seventeen cases (47.22%) had at least one risk factor for severe COVID-19 disease and 14 (38.89%) were admitted at some point to the ICU.

Conclusions

In our sample, delirium was the main cause for mental or behavioural symptoms in COVID-19 patients. However, we observed a wide array of presentations in our center. A larger sample would allow to better characterize this often-overlooked symptoms and identify risk factors to psychiatric syndromes.

Disclosure

No significant relationships.

ADCK2 Haploinsufficiency Reduces Mitochondrial Lipid Oxidation and Causes Myopathy Associated with CoQ Deficiency

Fatty acids and glucose are the main bioenergetic substrates in mammals. Impairment of mitochondrial fatty acid oxidation causes mitochondrial myopathy leading to decreased physical performance. Here, we report that haploinsufficiency of ADCK2, a member of the aarF domain-containing mitochondrial protein kinase family, in human is associated with liver dysfunction and severe mitochondrial myopathy with lipid droplets in skeletal muscle. In order to better understand the etiology of this rare disorder, we generated a heterozygous Adck2 knockout mouse model to perform in vivo and cellular studies using integrated analysis of physiological and omics data (transcriptomics–metabolomics). The data showed that Adck2+/− mice exhibited impaired fatty acid oxidation, liver dysfunction, and mitochondrial myopathy in skeletal muscle resulting in lower physical performance. Significant decrease in Coenzyme Q (CoQ) biosynthesis was observed and supplementation with CoQ partially rescued the phenotype both in the human subject and mouse model. These results indicate that ADCK2 is involved in organismal fatty acid metabolism and in CoQ biosynthesis in skeletal muscle. We propose that patients with isolated myopathies and myopathies involving lipid accumulation be tested for possible ADCK2 defect as they are likely to be responsive to CoQ supplementation.

Long-Term Safety of In Utero Exposure to Anti-TNFα Drugs for the Treatment of Inflammatory Bowel Disease: Results from the Multicenter European TEDDY Study

OBJECTIVES

The long-term safety of exposure to anti-tumor necrosis factor (anti-TNFα) drugs during pregnancy has received little attention. We aimed to compare the relative risk of severe infections in children of mothers with inflammatory bowel disease (IBD) who were exposed to anti-TNFα drugs in utero with that of children who were not exposed to the drugs.

METHODS

Retrospective multicenter cohort study. Exposed cohort: children from mothers with IBD receiving anti-TNFα medication (with or without thiopurines) at any time during pregnancy or during the 3 months before conception. Non-exposed cohort: children from mothers with IBD not treated with anti-TNFα agents or thiopurines at any time during pregnancy or the 3 months before conception. The cumulative incidence of severe infections after birth was estimated using Kaplan-Meier curves, which were compared using the log-rank test. Cox-regression analysis was performed to identify potential predictive factors for severe infections in the offspring.

RESULTS

The study population comprised 841 children, of whom 388 (46%) had been exposed to anti-TNFα agents. Median follow-up after delivery was 47 months in the exposed group and 68 months in the non-exposed group. Both univariate and multivariate analysis showed the incidence rate of severe infections to be similar in non-exposed and exposed children (1.6% vs. 2.8% per person-year, hazard ratio 1.2 (95% confidence interval 0.8-1.8)). In the multivariate analysis, preterm delivery was the only variable associated with a higher risk of severe infection (2.5% (1.5-4.3)).

CONCLUSIONS

In utero exposure to anti-TNFα drugs does not seem to be associated with increased short-term or long-term risk of severe infections in children.

Tuberculosis in Anti-Tumour Necrosis Factor-treated Inflammatory Bowel Disease Patients After the Implementation of Preventive Measures: Compliance With Recommendations and Safety of Retreatment

BACKGROUND AND AIMS

Despite having adopted preventive measures, tuberculosis (TB) may still occur in patients with inflammatory bowel disease (IBD) treated with anti-tumour necrosis factor (anti-TNF). Data on the causes and characteristics of TB cases in this scenario are lacking. Our aim was to describe the characteristics of TB in anti-TNF-treated IBD patients after the publication of the Spanish TB prevention guidelines in IBD patients and to evaluate the safety of restarting anti-TNF after a TB diagnosis.

METHODS

In this multicentre, retrospective, descriptive study, TB cases from Spanish hospitals were collected. Continuous variables were reported as mean and standard deviation or median and interquartile range. Categorical variables were described as absolute and relative frequencies and their confidence intervals when necessary.

RESULTS

We collected 50 TB cases in anti-TNF-treated IBD patients, 60% male, median age 37.3 years (interquartile range [IQR] 30.4-47). Median latency between anti-TNF initiation and first TB symptoms was 155.5 days (IQR 88-301); 34% of TB cases were disseminated and 26% extrapulmonary. In 30 patients (60%), TB cases developed despite compliance with recommended preventive measures; *not performing 2-step TST (tuberculin skin test) was the main failure in compliance with recommendations. In 17 patients (34%) anti-TNF was restarted after a median of 13 months (IQR 7.1-17.3) and there were no cases of TB reactivation.

CONCLUSIONS

Tuberculosis could still occur in anti-TNF-treated IBD patients despite compliance with recommended preventive measures. A significant number of cases developed when these recommendations were not followed. Restarting anti-TNF treatment in these patients seems to be safe.

Standardization of the homogeneous mobility shift assay protocol for evaluation of anti-infliximab antibodies. Application of the method to Crohn's disease patients treated with infliximab

BACKGROUND

The availability of a quantitative method to measure anti-infliximab (IFX) antibodies (ATI) would facilitate the implementation of therapeutic drug monitoring in clinical decision-making. Our aim was to standardize the homogeneous mobility shift assay (HMSA) used in the measure of ATI levels.

METHODS

In this prospective longitudinal multicenter study, 50 IFX-treated Crohn's disease (CD) patients were followed up for 54weeks. During this period 360 human serum samples were analysed. Monomeric ATI levels were measured by a quantitative HMSA-method using an anti-IFX calibrator. IFX trough levels measured by ELISA were correlated with ATI levels.

RESULTS

Using HMSA and a pure anti-idiotypic monoclonal antibody specific for IFX (anti-IFX calibrator), we measured the levels of monomeric ATI generated in Crohn's disease patients treated with IFX. Anti-IFX calibrator allowed to quantify monomeric antibodies against IFX with a low limit of quantification (3nM). The threshold level of ATI in order to classify the immunogenicity of the patients was 10nM. We observed that 24% (12/50) of IFX-treated patients developed ATI (>10nM) during the observation period (54weeks). Serum concentration of ATI higher than 10nM dramatically increased the probability (OR=51.1; 95% CI: 20.4-128.0; p<0.0001) of presenting low levels of IFX (⩽1.5nM) in serum, as observed in some CD patients treated with standard doses of the drug.

CONCLUSIONS

The HMSA-method described here allows an accurate quantification of ATI concentration in international units (IU) and therefore it could be useful in the study of the relationship between ATI concentration, infliximab level and the clinical response to the drug.

Nonpalpable Breast Lesion

One hundred and fifty-six patients with suspect nonpalpable breast lesion underwent stereotaxic core needle aspiration biopsy (SCNAB) with a single pass in an upright “add-on” stereotaxic device using a manual 1.6-mm needle (16 G), to determine whether the results were comparable to results of SCNAB with a multiple-pass technique. Of the 69 carcinomas, 51 (74%) were correctly diagnosed and definitive surgical therapy, without surgical biopsy, was performed in 42 of the 50 invasive carcinomas (84%) and in 9 of the 19 noninvasive carcinomas (47%). Ten noninvasive carcinomas and 4 invasive carcinomas, discovered by microcalcifications or distortion on the mammograms, form 78% of the false-negative results. There were no false-positive results. Vasovagal reactions occurred in 11% of the procedures. Although the results were acceptable in patients with invasive carcinoma, more than one needle pass is necessary for greater diagnostic accuracy of SCNAB, especially in patients with only microcalcifications or distortion on the mammogram.

Effect of Chondroitin Sulphate on Pro-Inflammatory Mediators and Disease Activity in Patients with Inflammatory Bowel Disease

BACKGROUND/AIMS

To evaluate the incidence rate of relapse in patients with inflammatory bowel disease (IBD) undergoing chondroitin sulphate (CS) treatment and its effect on the concentrations of several pro-inflammatory proteins.

METHODS

Prospective, observational, 12-month follow-up study in patients with IBD in remission, starting CS (Condrosan®, Bioiberica S.A.) treatment for osteoarthritis (OA). Crohn's Disease Activity Index and modified Truelove-Witts severity index were calculated for Crohn's disease and ulcerative colitis (UC) respectively. Levels of vascular endothelial growth factor (VEGFA), -C, fibroblast growth factor 2, hepatocyte growth factor, angiopoietin (Ang)-1, Ang-2, transforming growth factor beta, tumour necrosis factor alpha, interleukin (IL)-1β, IL-6, IL-12, IL-17, IL-23, intracellular adhesion molecule-1, vascular adhesion molecule-1, matrix metalloproteinase-3 and PGE2 were quantified by ELISA. OA joint pain was evaluated using a visual analogue scale.

RESULTS

A total of 37 patients (19 UC and 18 Crohn's disease) were included. The mean values for OA joint pain decreased after 12 months from 5.9 ± 2.8 to 3.0 ± 2.3 (p < 0.05). Only 1 patient (with UC) flared during follow-up. The incidence rate of relapse was 3.4% per patient-year of follow-up. Mean serum VEGFA levels increased between baseline (492 pg/ml) and 12-month treatment (799 pg/ml; p < 0.05).

CONCLUSION

The incidence of IBD relapse in patients under CS treatment was lower than that generally reported. This treatment might modulate VEGFA. CS decreases OA-related pain in patients with IBD.

Cost-effectiveness of sofosbuvir for the treatment of chronic hepatitis C-infected patients

The efficacy of treatment for hepatitis C genotype 1 infection has significantly improved with the introduction of first-generation protease inhibitors. However, there remains a need for effective treatments for patients infected with other genotypes, for nonresponders and patients unsuitable for interferon. Sofosbuvir is the first nucleotide polymerase inhibitor with pan-genotypic activity. Sofosbuvir-based regimens have resulted in >90% sustained virological response across treatment-naïve genotype 1-6 patients in five phase III clinical trials of sofosbuvir administered with ribavirin or pegylated interferon and ribavirin. This analysis evaluates the cost-effectiveness of sofosbuvir within the current licensed indication, for genotype 1-6 in the UK. A Markov model followed a cohort of 10 000 patients over lifetime, with approximately 20% initiating treatment for compensated cirrhosis. Sofosbuvir-regimens were compared to telaprevir, boceprevir, pegylated interferon and ribavirin, or no treatment. Costs and outcomes were discounted at 3.5%. The cost perspective utilized costs applicable to the National Health Service in the UK. Sofosbuvir proved to be cost-effective in most patient populations with incremental cost-effectiveness ratios (ICERs) at £11 836/QALY and £7292/QALY against telaprevir and boceprevir, respectively. In genotype 3, sofosbuvir had a weighted ICER of £18 761/QALY. Sofosbuvir-based regimens are a cost-effective option for the majority of hepatitis C-infected patients in the United Kingdom although the incremental cost-effectiveness varies by genotype and regimen. Sofosbuvir and ribavirin is an alternative regimen for patients unsuitable for interferon.

Optimizing use of the structural chemical analyser (variable pressure FESEM-EDX Raman spectroscopy) on micro-size complex historical paintings characterization

The novel Structural Chemical Analyser (hyphenated Raman spectroscopy and scanning electron microscopy equipped with an X-ray detector) is gaining popularity since it allows 3-D morphological studies and elemental, molecular, structural and electronic analyses of a single complex micro-sized sample without transfer between instruments. However, its full potential remains unexploited in painting heritage where simultaneous identification of inorganic and organic materials in paintings is critically yet unresolved. Despite benefits and drawbacks shown in literature, new challenges have to be faced analysing multifaceted paint specimens. SEM-Structural Chemical Analyser systems differ since they are fabricated ad hoc by request. As configuration influences the procedure to optimize analyses, likewise analytical protocols have to be designed ad hoc. This paper deals with the optimization of the analytical procedure of a Variable Pressure Field Emission scanning electron microscopy equipped with an X-ray detector Raman spectroscopy system to analyse historical paint samples. We address essential parameters, technical challenges and limitations raised from analysing paint stratigraphies, archaeological samples and loose pigments. We show that accurate data interpretation requires comprehensive knowledge of factors affecting Raman spectra. We tackled: (i) the in-FESEM-Raman spectroscopy analytical sequence, (ii) correlations between FESEM and Structural Chemical Analyser/laser analytical position, (iii) Raman signal intensity under different VP-FESEM vacuum modes, (iv) carbon deposition on samples under FESEM low-vacuum mode, (v) crystal nature and morphology, (vi) depth of focus and (vii) surface-enhanced Raman scattering effect. We recommend careful planning of analysis strategies prior to research which, although time consuming, guarantees reliable results. The ultimate goal of this paper is to help to guide future users of a FESEM-Structural Chemical Analyser system in order to increase applications.

Invertebrate models for coenzyme q10 deficiency

The human syndrome of coenzyme Q (CoQ) deficiency is a heterogeneous mitochondrial disease characterized by a diminution of CoQ content in cells and tissues that affects all the electron transport processes CoQ is responsible for, like the electron transference in mitochondria for respiration and ATP production and the antioxidant capacity that it exerts in membranes and lipoproteins. Supplementation with external CoQ is the main attempt to address these pathologies, but quite variable results have been obtained ranging from little response to a dramatic recovery. Here, we present the importance of modeling human CoQ deficiencies in animal models to understand the genetics and the pathology of this disease, although the election of an organism is crucial and can sometimes be controversial. Bacteria and yeast harboring mutations that lead to CoQ deficiency are unable to grow if they have to respire but develop without any problems on media with fermentable carbon sources. The complete lack of CoQ in mammals causes embryonic lethality, whereas other mutations produce tissue-specific diseases as in humans. However, working with transgenic mammals is time and cost intensive, with no assurance of obtaining results. Caenorhabditis elegans and Drosophila melanogaster have been used for years as organisms to study embryonic development, biogenesis, degenerative pathologies, and aging because of the genetic facilities and the speed of working with these animal models. In this review, we summarize several attempts to model reliable human CoQ deficiencies in invertebrates, focusing on mutant phenotypes pretty similar to those observed in human patients.

Survival transcriptome in the coenzyme Q10 deficiency syndrome is acquired by epigenetic modifications: a modelling study for human coenzyme Q10 deficiencies

OBJECTIVES

Coenzyme Q10 (CoQ10) deficiency syndrome is a rare condition that causes mitochondrial dysfunction and includes a variety of clinical presentations as encephalomyopathy, ataxia and renal failure. First, we sought to set up what all have in common, and then investigate why CoQ10 supplementation reverses the bioenergetics alterations in cultured cells but not all the cellular phenotypes. DESIGN MODELLING STUDY: This work models the transcriptome of human CoQ10 deficiency syndrome in primary fibroblast from patients and study the genetic response to CoQ10 treatment in these cells.

SETTING

Four hospitals and medical centres from Spain, Italy and the USA, and two research laboratories from Spain and the USA.

PARTICIPANTS

Primary cells were collected from patients in the above centres.

MEASUREMENTS

We characterised by microarray analysis the expression profile of fibroblasts from seven CoQ10-deficient patients (three had primary deficiency and four had a secondary form) and aged-matched controls, before and after CoQ10 supplementation. Results were validated by Q-RT-PCR. The profile of DNA (CpG) methylation was evaluated for a subset of gene with displayed altered expression.

RESULTS

CoQ10-deficient fibroblasts (independently from the aetiology) showed a common transcriptomic profile that promotes cell survival by activating cell cycle and growth, cell stress responses and inhibiting cell death and immune responses. Energy production was supported mainly by glycolysis while CoQ10 supplementation restored oxidative phosphorylation. Expression of genes involved in cell death pathways was partially restored by treatment, while genes involved in differentiation, cell cycle and growth were not affected. Stably demethylated genes were unaffected by treatment whereas we observed restored gene expression in either non-methylated genes or those with an unchanged methylation pattern.

CONCLUSIONS

CoQ10 deficiency induces a specific transcriptomic profile that promotes cell survival, which is only partially rescued by CoQ10 supplementation.

Systematic review: antibodies and anti-TNF-α levels in inflammatory bowel disease

BACKGROUND

The associations between clinical efficacy and infusion reactions with anti-TNF-α drug levels and the presence of antibodies against the drug have been described. However, the clinical utility of these tests in routine clinical practice remains unclear.

AIMS

To examine the clinical significance of the development of antibodies against anti-TNF-α drugs and the relationship between the efficacy of these drugs and their serum levels. We also studied the clinical utility of testing for anti-TNF-α antibodies and measuring drug serum levels to optimise treatment of patients with inflammatory bowel disease (IBD) receiving these agents.

METHODS

A systematic review was undertaken based on electronic searches of the PubMed database from the earliest record to February 2012. The reference lists of all relevant articles and abstracts from meetings were also consulted.

RESULTS

We observed a close relationship between trough levels of anti-TNF-α drug and maintenance of response to these drugs. The role of antibodies in loss of response seems to be limited to their effect favouring the clearance of the drug. The risk of infusion reactions, but not of delayed hypersensitivity reactions, is higher in patients with antibodies against the anti-TNF-α drug. Testing anti-TNF-α drug and antibody levels, together with clinical and endoscopic or radiological assessment, seems useful when attempting to optimise therapy and prevent inappropriate management of IBD patients.

CONCLUSION

Measurement of serum anti-TNF-α trough levels and antibody titres could prove useful in therapeutic drug monitoring in IBD patients treated with anti-TNF-α agents.

Analysis of hepatitis C virus core encoding sequences in chronically infected patients reveals mutability, predominance, genetic history and potential impact on therapy of Cuban genotype 1b isolates

BACKGROUND AND OBJECTIVES

Hepatitis C virus (HCV) genotypes are relevant to epidemiological questions, vaccine development, and clinical management of chronic HCV infection. In the present work, we aimed at investigating HCV genotype, variability and genetic history of HCV isolates in Cuba from a sample of chronically infected patients.

MATERIAL AND METHODS

A prospective study, involving 73 Cuban anti-HCV positive patients, was carried out. RT-PCR and phylogenetic analysis was employed to determine HCV genotypes. Divergence dates and demographic parameters in a Bayesian coalescent framework were estimated, as implemented in BEAST v1.4.8.

RESULTS

HCV RNA was undetectable in 15 patients that received antiviral therapy. All HCV RNA positive patients, 58, were infected with genotype 1, three of them with subtype 1a and 55 with subtype 1b. The analysis of the DNA sequence coding for a core fragment, spanning nt positions 435-816 (relative to strain H77), revealed high percent (96.7% +/- 0.8%) nucleotide identity within Cuban HCV subtype 1b sequences. However, 56.7% and 20% of 30 analyzed individuals had changes in the core region in a six-month interval, at the nucleotide and amino acid level, respectively. Mutations involving aa changes were mainly found in the region encompassed between aa 70 and 106 of the core protein, with only one isolate showing a point mutation at position 43. Interestingly, some of the observed changes seem to be reversions and might in fact contribute to reducing the variability of this region. The estimated date for the most recent common ancestor of HCV genotype 1b Cuban isolates is 1969 (CI, 1953 to 1977).

DISCUSSION

Analysis of HCV core encoding sequences from chronic patients reveals mutability of genotype 1b isolates in Cuba, which seem to be predominant and rapidly multiplied during the eighty decade of last century, and might limit the benefits obtained from current antiviral therapy.

Performance evaluation of paediatric propofol pharmacokinetic models in healthy young children

BACKGROUND

The performance of eight currently available paediatric propofol pharmacokinetic models in target-controlled infusions (TCIs) was assessed, in healthy children from 3 to 26 months of age.

METHODS

Forty-one, ASA I-II children, aged 3-26 months were studied. After the induction of general anaesthesia with sevoflurane and remifentanil, a propofol bolus dose of 2.5 mg kg(-1) followed by an infusion of 8 mg kg(-1) h(-1) was given. Arterial blood samples were collected at 1, 2, 3, 5, 10, 20, 40, and 60 min post-bolus, at the end of surgery, and at 1, 3, 5, 30, 60, and 120 min after stopping the infusion. Model performance was visually inspected with measured/predicted plots. Median performance error (MDPE) and the median absolute performance error (MDAPE) were calculated to measure bias and accuracy of each model.

RESULTS

Performance of the eight models tested differed markedly during the different stages of propofol administration. Most models underestimated propofol concentration 1 min after the bolus dose, suggesting an overestimation of the initial volume of distribution. Six of the eight models tested were within the accepted limits of performance (MDPE<20% and MDAPE<30%). The model derived by Short and colleagues performed best.

CONCLUSIONS

Our results suggest that six of the eight models tested perform well in young children. Since most models overestimate the initial volume of distribution, the use for TCI might result in the administration of larger bolus doses than necessary.

Mercaptopurine rescue after azathioprine-induced liver injury in inflammatory bowel disease

BACKGROUND

Azathioprine (AZA) liver toxicity arises in approximately 3% of inflammatory bowel disease patients and may result in treatment discontinuation.

AIM

To describe the tolerance to mercaptopurine (MP) in patients with previous AZA-related liver injury.

METHODS

Retrospective description of 31 patients (14 Crohn's, 17 ulcerative colitis), in which AZA therapy was interrupted because of liver injury, with MP started as alternative therapy.

RESULTS

Mean AZA dose was 2.2 +/- 0.4 mg x kg/day. Median (interquartile range) of AZA exposure when liver injury was detected was 2 months (1-5.2). The type of AZA-related injury was cytolitic in 32%, cholestatic in 39% and mixed in 29%. After a median of 2.5 months (0.7-5.2), the therapy was switched to MP at a mean dose of 1.3 +/- 0.2 mg x kg/day. Median of follow-up of MP therapy was 32 months (8-54). In 87.1% of patients (95%CI: 70-96%), MP was tolerated without further liver injury; of these, 77.4% tolerated full MP doses and 9.7% tolerated lower doses. In a further cohort of 12.9% of patients, (95%CI: 3-29%), liver injury reappeared (two cholestasis, two mixed), 1-3 months after the onset of MP exposure.

CONCLUSION

The administration of MP is a good alternative in patients with AZA-related liver injury, before thiopurines are definitely discarded.

Immunogenicity of CIGB-230, a therapeutic DNA vaccine preparation, in HCV-chronically infected individuals in a Phase I clinical trial

Hepatitis C virus (HCV) is a worldwide health problem. No vaccine is available against this pathogen and therapeutic treatments currently in use are of limited efficacy. In the present study, the immunogenicity of the therapeutic vaccine candidate CIGB-230, based on the mixture of pIDKE2, a plasmid expressing HCV structural antigens, with a recombinant HCV core protein, Co.120, was evaluated. CIGB-230 was administered by intramuscular injection on weeks 0, 4, 8, 12, 16 and 20 to 15 HCV-chronically infected individuals, non-responders to previous treatment with interferon (IFN) plus ribavirin. Interestingly, following the final immunization, neutralizing antibody responses against heterologous viral pseudoparticles were modified in eight individuals, including six de novo responders. In addition, 73% of vaccinees exhibited specific T cell proliferative response and T cell IFN-gamma secretory response 24 weeks after primary immunization with CIGB-230. Furthermore, 33.3% of individuals developed de novo cellular immune response against HCV core and the number of patients (46.7% at the end of treatment) with cellular immune response against more than one HCV structural antigen increased during vaccination (P = 0.046). In addition, despite persistent detection of HCV RNA, more than 40% percent of vaccinated individuals improved or stabilized liver histology, particularly reducing fibrosis, which correlated with cellular immune response against more than one HCV antigen (P = 0.0053). In conclusion, CIGB-230 is a promising candidate for effective therapeutic interventions based on its ability for enhancing the immune response in HCV chronically infected individuals.

Eco-efficient concretes: the effects of using recycled ceramic material from sanitary installations on the mechanical properties of concrete

The aim of this research was to investigate some of the physical and mechanical properties of concrete mixed under laboratory conditions, where different proportions of coarse aggregate materials were substituted by porcelain from sanitary installations. The results of the tests show that the concrete produced has the same mechanical characteristics as conventional concrete, thus opening a door to selective recycling of sanitary porcelain and its use in the production of concrete.

Therapeutic drug monitoring of mycophenolic acid in kidney transplant patients: a abbreviated sampling strategy

Mycophenolic acid (MPA) levels have demonstrated a good correlation with clinical outcomes, but with great pharmacokinetic variability between patients. Therapeutic drug monitoring (TDM) is recommended to include a 12-hour area under the concentration-time curve (AUC). Since full AUC estimates are not practical for routine monitoring, limited sampling strategies have been suggested. We evaluated MPA pharmacokinetics in 18 stable renal transplant patients receiving mycophenolate mofetil (MMF) as part of their immunosuppressive therapy. The correlation between measured and estimated AUC was assessed using 4 different sparse sampling algorithms. The mean values for C(0) and AUC(0-6h) were 1.8 +/- 1.2 mg/L and 31.1 +/- 14.8 mg*h/L, respectively. The dose-corrected AUC(0-6h) was 35.4 +/- 17.9 mg*h/L. Regarding the single time points, C(0) showed a low correlation with AUC(0-6h) (r(2) = .34); C(1.5), the best correlation (r(2) = .72); and C(3), the worst (r(2) = .07). Sparse sample algorithms used to estimate 12-hour AUC including C(0), C(1), C(2), C(3), C(4), and/or C(6) showed a good correlation with the calculated AUC(0-6) (r(2) = .81-.96). The algorithm that used C(0), C(1), C(2), and C(4) showed the best correlation, but we also found a good correlation (r(2) = .91) with C(0), C(1), and C(2). Based on these results, we have suggested using the 3-point algorithm (C(0), C(1), and C(2)) for MPA TDM in stable renal transplant patients due to the good correlation with drug exposure and better functionality than an algorithm using a 4-hour postdose measurement.

Differences in the frequency and distribution of BRCA1 and BRCA2 mutations in breast/ovarian cancer cases from the Basque country with respect to the Spanish population: implications for genetic counselling

The prevalence of unique and recurrent BRCA1 and BRCA2 pathogenic mutations and unclassified variants varies among different populations. Two hundred and thirty-six breast and/or ovarian cancer patients were analysed to clarify the role of these genes in the Basque Country. We also studied 130 healthy women from the general population from the same region. Fifteen different pathological mutations were found in 16 index cases: 10 truncating mutations, 4 missense mutations and 1 splicing mutation. c.3002_3003insT and c.5788_5789delGT, both in exon 11 of BRCA2 have not previously been described. No pathological mutations were found in cases of sporadic juvenile breast cancer. There are no recurrent mutations in our population; apart from the mutation c.9254_9258del5, which appears in only two index cases. We have also found a lot of variants whose effect is unknown. From these variants, 17 have not previously been described: 6 missenses, 6 synonymous and 5 alterations in intronic regions. We would like to highlight the fact that 14.3% of patients with 3 or more cases of breast cancer in the family, and 16.7% of patients with family history of breast and ovarian cancer, present a pathological mutation in BRCA1 or BRCA2. This manuscript demonstrates that each population can have different mutations and due to this, Genetic Counselling and selection criteria must be different for each population. Furthermore, this article describes for the first time some new mutations and unclassified variants found in our population.

In vitro quantitative determination of ophthalmic irritancy by the chorioallantoic membrane test with trypan blue staining as alternative to eye irritation test

The damage provoked by some substances on the chicken egg's chorioallantoic membrane (CAM) is used as an alternative assay to determine ocular irritation. There is good prediction of the eye irritation when compared to the in vivo Draize method. Nevertheless, this assay has some limitations, such as subjectivity. Hagino et al. developed an objective evaluation technique using the amount of trypan blue absorbed at the site of treatment as an indicator of injury to the CAM. The present work was aimed at the determination of ocular irritation of 21 substances (chemicals and cosmetics). We used the spectrophotometric quantification by trypan blue staining of the damage produced on CAM, of fertile chicken eggs. Results were compared with the values obtained by the traditional Draize assay. We observed a good correlation (r=0.835; p<0.0001) between the amount of dye absorbed by the CAM and the Draize eye irritation test score. The r values were 0.688; p<0.05 for cosmetics and 0.925; p<0.0001 for chemicals. Three chemicals turned as false positive and one cosmetic substance as false negative. The CAM-TBS assay is inexpensive, simple and provides an in vitro alternative method to predict the damage that chemical substances or cosmetics can cause to the ocular structures.

Two-stage treatment with preoperative endoscopic retrograde cholangiopancreatography (ERCP) compared with single-stage treatment with intraoperative ERCP for patients with symptomatic cholelithiasis with possible choledocholithiasis

BACKGROUND AND STUDY AIMS

An ideal treatment for choledocholithiasis in the laparoscopic era has not been established. The objective of this study was to elucidate whether a treatment strategy of performing intraoperative endoscopic retrograde cholangiopancreatography (ERCP) during laparascopic cholecystectomy (when choledocholithiasis is confirmed by intraoperative cholangiography) is better for patients with suspected common bile duct stones than the current strategy (preoperative ERCP followed by laparoscopic cholecystectomy).

PATIENTS AND METHODS

This was a prospective randomized study to evaluate which of these two approaches was most benefit- and cost-effective for patients with intermediate risk of choledocholithiasis. Patients underwent either preoperative ERCP followed by a laparoscopic cholecystectomy a few weeks later (the "preoperative ERCP" group) or intraoperative ERCP (the "intraoperative ERCP" group). Intraoperative ERCP was performed using the rendezvous technique.

RESULTS

There were 64 patients in the preoperative ERCP group and 59 patients in the intraoperative ERCP group. The demographic and clinical characteristics of the two groups were similar, except that the bilirubin and gamma-glutamyl transferase (GGT) levels and the number of patients treated on an inpatient basis were higher in the preoperative ERCP group. Success rates were similar (96.6 % in the preoperative ERCP group vs. 90.2 % in the intraoperative ERCP group in the per-protocol study). Total morbidity, post-ERCP morbidity, and post-ERCP acute pancreatitis rates were higher in the preoperative ERCP group, but there were no differences between the two groups in the frequency of residual common bile duct stones, the conversion rate to open cholecystectomy, or surgical morbidity. The length of hospital stay and costs were lower in the intraoperative ERCP group despite the longer surgical times in this group. Univariate analysis did not find any relationship between morbidity and total bilirubin or GGT. Logistic regression analysis confirmed that morbidity was related only to the treatment group and the time spent in the operating room: the relative risk (RR) was 4.37 for morbidity and 1.015 for the time spent in the operating room); the RR for papillotomy was 5.49.

CONCLUSIONS

Both treatment approaches were equally effective but the intraoperative ERCP group had less morbidity, a shorter hospital stay, and reduced costs. The lower morbidity in the intraoperative ERCP group resulted from the lower rate of papillotomy and lower rates of post-ERCP pancreatitis and cholecystitis. Total morbidity was principally related to the type of treatment approach used.

Clustering of polarity reversals of the geomagnetic field

Often in nature the temporal distribution of inhomogeneous stochastic point processes can be modeled as a realization of renewal Poisson processes with a variable rate. Here we investigate one of the classical examples, namely, the temporal distribution of polarity reversals of the geomagnetic field. In spite of the commonly used underlying hypothesis, we show that this process strongly departs from a Poisson statistics, the origin of this failure stemming from the presence of temporal clustering. We find that a Lévy statistics is able to reproduce paleomagnetic data, thus suggesting the presence of long-range correlations in the underlying dynamo process.

Comparative study of red blood cell method in rat and calves blood as alternatives of Draize eye irritation test

INTRODUCTION

Red blood cell assay (RBC) is used to estimate potential irritation of tensioactive agents and detergents. Cell membrane lysis and cell protein denaturation are measured photometrically. This study was aimed to determine if rat blood cells can be used to predict eye potential irritation in the same way of calves blood cells in RBC assay.

METHODS

We evaluated 20 cosmetic formulations using rat and calves blood according to INVITOX protocol No 37. Data of media hemolysis concentration, denaturation index and the ratio of both parameters were compared with in vivo data of eye irritancy.

RESULTS

There was a significant difference (p<0.01) between H50 value when evaluated the standard SDS with red blood cell method in rat and calves blood. According to the exact probability of Fisher taking as approach the acceptance or rejection of the substance there are no significant differences between in vitro assay with calves blood and in vivo results. Not happening the same way for the RBC assay with rat blood where significant differences were obtained (p<0.01) among the classification of in vitro and in vivo test.

DISCUSSION

The RBC assay using calves blood showed better results. Several test substances were false negatives with rat blood. This high false negative rate would be correctly identified by the animal test but it may also lead to increased animal consumption. For that RBC assay with calf blood cells is preferable to the employment of rat blood as screening method with a reduction and refinement strategy.

Immunohistochemical prognostic index for breast cancer in young women

AIMS

Women under 35 years of age comprise a small proportion of patients with breast cancer, but determining their prognosis can be difficult. This prospective, multivariate study looked at several factors with the aim of obtaining a useful index to evaluate the prognosis of these women.

METHODS

In total, 108 patients below 35 years of age affected by invasive ductal carcinoma without distant metastasis were studied. The mean duration of the follow up period was six years. Histopathological (tumour size, histological grade, and lymph node stage) and immunohistochemical (c-erbB-2, p53, oestrogen receptor, and progesterone receptor) factors were measured in all patients, and the Nottingham prognostic index (NPI) was then calculated. An immunohistochemical prognostic index (IHPI) was created using the arithmetic sum of the four individual immunohistochemical factors.

RESULTS

In univariate assessment of survival, all the studied factors yielded a significant association with either overall survival or disease free survival, except for c-erbB-2 and p53 with disease free survival. In univariate calculation of risk, all the factors gave significant results; however, in multivariate analysis only tumour size, histological grade, and progesterone receptor were significant. Both NPI and IHPI correlated significantly with prognosis. In multivariate regression analysis, IHPI correlated with tumour size and there was a significant interaction between both variables.

CONCLUSION

IHPI is very useful in determining the prognosis of tumours < or = 2 cm and of moderate use for tumours > 2, although it has no use in tumours > 5 cm.

Immunological evaluation of Escherichia coli-derived hepatitis C virus second envelope protein (E2) variants

Two variants of the hepatitis C virus (HCV) E2 envelope protein, lacking the C-terminal domain and comprising amino acids 458-650 (E2A) and 382-605 (E2C), respectively, were efficiently produced in BL21 (DE3) Escherichia coli cells. E2A and E2C were used to immunize mice. The E2C variant induced the maximal mean antibody titer. Anti-E2C mouse sera reacted mainly with E2 synthetic peptides covering the 70 amino acid N-terminal region of the E2 protein. Moreover, a panel of anti-HCV positive human sera recognized only the E2C protein (28.2%) and the synthetic peptide covering the HVR-1 of the E2 protein (23.1%). These data indicate the existence of an immunologically relevant region in the HVR-1 of the HCV E2 protein.

Value of limited necropsy in HIV-positive patients

We performed limited autopsy with histological examination of tissue cores obtained percutaneously using the Tru-Cut needle and the Jamshidi trocar in 150 adult HIV-positive patients. Data were compared retrospectively with the antemortem clinical diagnosis. Eighty-one percent of the patients were male, and 78% were intravenous drug users. Specimens were obtained from the brain, liver, lung, bone marrow, and kidney of most patients. The main findings included liver cirrhosis in 22 cases (associated with HCV infection in 81%), Pneumocystis carinii pneumonia in 21, Cytomegalovirus (CMV) infection in 19, Mycobacterium avium-intracellulaire (MAI) infection in 17, bacterial pneumonia in 14, tuberculosis in 12, and lymphoma in 13 cases. Forty-six (30.6%) patients had at least one clinical diagnosis that was confirmed by autopsy, i.e., there was 40.6% agreement between pre- and postmortem findings. Forty-six (30.6%) patients had at least one clinical diagnosis that was not confirmed at autopsy, whereas 41 (27.3%) had at least one AIDS-related or unrelated disease that was not suspected clinically. The results obtained by limited autopsy are principally comparable to those achieved by full necropsy, with the advantages of decreasing the contagious risk, saving cost and time, including a rapid final diagnosis, and easily obtaining the consent for postmortem examination so that necropsy studies may be performed on a larger number of patients, thus contributing to a better understanding of the spectrum of HIV infection in our environment.

Expression and immunological evaluation of the Escherichia coli-derived hepatitis C virus envelope E1 protein

Immunological response against envelope protein E1 is very important in natural hepatitis C virus (HCV) infection, although it is insufficient to clear the viraemia. The HCV genomic region encoding the first 149 amino acids of the envelope E1 protein (E1(340), amino acids 192-340) was expressed in Escherichia coli (to a level of 30% of the whole cellular proteins) and purified to 85%. We measured the immune response in rabbits and mice as well as the reactivity against 37 human sera raised against the whole recombinant protein and E1-encoding peptides. From this, 51.1% of human sera were found to react with E1(340). High-level antibodies against E1(340) were obtained in rabbits and mice when immunized. These antibodies had a similar peptide-recognition pattern to that described previously for human sera. The most reactive region was located at the N-terminus of the E1 protein. Cellular immunity in mice was evaluated by delayed-type hypersensitivity assay. It revealed the induction of a CD4+ T-cell-mediated response by this protein. This E1(340) protein and the animal-derived anti-E1 sera are immunological tools that could aid in the monitoring and development of anti-HCV therapies.

Nonpalpable breast lesion. Stereotaxic core needle aspiration biopsy with a single pass

One hundred and fifty-six patients with suspect nonpalpable breast lesion underwent stereotaxic core needle aspiration biopsy (SCNAB) with a single pass in an upright "add-on" stereotaxic device using a manual 1.6-mm needle (16 G), to determine whether the results were comparable to results of SCNAB with a multiple-pass technique. Of the 69 carcinomas, 51 (74%) were correctly diagnosed and definitive surgical therapy, without surgical biopsy, was performed in 42 of the 50 invasive carcinomas (84%) and in 9 of the 19 noninvasive carcinomas (47%). Ten noninvasive carcinomas and 4 invasive carcinomas, discovered by microcalcifications or distortion on the mammograms, form 78% of the false-negative results. There were no false-positive results. Vasovagal reactions occurred in 11% of the procedures. Although the results were acceptable in patients with invasive carcinoma, more than one needle pass is necessary for greater diagnostic accuracy of SCNAB, especially in patients with only microcalcifications or distortion on the mammogram.

Neutralizing antibodies against the peptide antibiotic AS-48: immunocytological studies

Antisera against the broad-spectrum peptide antibiotic AS-48 produced by Enterococcus faecalis were obtained from immunized rabbits. Appreciable antibody titers were obtained only after repeated immunization, suggesting a feeble antigenicity for AS-48. Upon incubation with AS-48, the antisera neutralized its bacteriolytic action on E. faecalis S-47, although the simultaneous addition of AS-48 and serum did not prevent lysis. Crude serum cross-reacted with outer envelope components of enterococci, although specific anti-AS-48 antibodies, purified by affinity chromatography, reacted only with AS-48-treated cells. Labelling with immunofluorescence and colloidal gold particles was carried out on sensitive and resistant bacterial species to determine the interaction of AS-48 with cell structures.

Hypokalemic adrenal crisis in a patient with AIDS

Electrolyte disorders have been reported frequently in patients with AIDS. Adrenal insufficiency has been associated with hyponatremia in this group of patients. We have presented the case of a patient with AIDS whose early course was complicated by hyponatremia, hypoglycemia, and hyperkalemia. Shortly thereafter, hypokalemia developed due to gastrointestinal potassium losses from diarrhea. Although cosyntropin stimulation testing later confirmed the diagnosis of adrenal insufficiency, it was not considered because of coexistent hypokalemia. Diarrhea in patients with AIDS and diminished adrenal reserve may invalidate hypokalemia as an exclusion criterion for the diagnosis of adrenal crisis.