Cationic exchange SPE combined with triple quadrupole UHPLC-MS/MS for detection of GHRHs in urine samples

The use of growth hormone-releasing hormones (GHRHs) is prohibited in sports according to the regulations of the World Anti-Doping Agency (WADA). Considering the complexity of urine samples and the low concentrations at which these analytes should be detected, analyzing GHRHs is a challenging task. In most of the studies, GHRHs are analyzed using UHPLC-HRMS with an orbitrap. The present developed and validated method for some GHRHs (tesamorelin, CJC-1295, sermorelin (GRF 1-29), sermorelin (3-29)-NH2, somatorelin) is based on the triple quadrupole UHPLC/MS-MS method with solid phase extraction (SPE) with weak cation exchange and is able to detect concentrations as low as 0.2 ng/mL (LOD), a limit of quantification (LOQ) at 0.6 ng/mL, and linearity across the range of 0.1 ng/mL to 1.2 ng/mL. The present method developed by our doping control laboratory was validated according to WADA technical documents for selectivity, limit of detection (LOD), carryover, reliability of detection, stability and recovery. The results show that the method has adequate recoveries and sensitivity, hence, it can be employed for routine screening in anti-doping laboratories.

Revisiting the dependence of retention factor on the content of organic component in the mobile phase in reversed-phase HPLC

In high-performance liquid chromatography, the dependence of retention factor k on volumetric fraction ϕ of organic phase is expressed by log k = F(ϕ) with F(ϕ) obtained by measuring log k at different ϕ values. From F(ϕ), a value kw is calculated by taking ϕ = 0. The equation log k = F(ϕ) is applied for predicting k, and kw is a descriptor of hydrophobic character of solutes and stationary phases. Calculated kw should not depend on the nature of organic component of mobile phase but extrapolation procedure leads to different kw for different organic components. The present study shows that the expression of F(ϕ) changes depending on the range of ϕ and the same function F(ϕ) cannot be used for the full range of ϕ from 0 to 1. Consequently, kw obtained by extrapolation of ϕ to zero is not correct because the expression of F(ϕ) was generated by fitting the data using ϕ with higher values. The present study shows the proper way to obtain the value of kw .

rJararacin, a recombinant disintegrin from Bothrops jararaca venom: Exploring its effects on hemostasis and thrombosis

Integrins are a family of heterodimeric transmembrane receptors which link the extracellular matrix to the cell cytoskeleton. These receptors play a role in many cellular processes: adhesion, proliferation, migration, apoptosis, and platelet aggregation, thus modulating a wide range of scenarios in health and disease. Therefore, integrins have been the target of new antithrombotic drugs. Disintegrins from snake venoms are recognized by the ability to modulate the activity of integrins, such as integrin αIIbβ3, a fundamental platelet glycoprotein, and αvβ3 expressed on tumor cells. For this reason, disintegrins are unique and potential tools for examining integrin-matrix interaction and the development of novel antithrombotic agents. The present study aims to obtain the recombinant form of jararacin and evaluate the secondary structure and its effects on hemostasis and thrombosis. rJararacin was expressed in the Pichia pastoris (P. pastoris) expression system and purified the recombinant protein with a yield of 40 mg/L of culture. The molecular mass (7722 Da) and internal sequence were confirmed by mass spectrometry. Structure and folding analysis were obtained by Circular Dichroism and ¹H Nuclear Magnetic Resonance spectra. Disintegrin structure reveals properly folded with the presence of β-sheet structure. rJararacin significantly demonstrated inhibition of the adhesion of B16F10 cells and platelets to the fibronectin matrix under static conditions. rJararacin inhibited platelet aggregation induced by ADP (IC₅₀ 95 nM), collagen (IC₅₀ 57 nM), and thrombin (IC₅₀ 22 nM) in a dose-dependent manner. This disintegrin also inhibited 81% and 94% of the adhesion of platelets to fibrinogen and collagen under continuous flow, respectively. In addition, rjararacin efficaciously prevents platelet aggregation in vitro and ex vivo with rat platelets and thrombus occlusion at an effective dose (5 mg/kg). The data here provides evidence that rjararacin possesses the potential as an αIIbβ3 antagonist, capable of preventing arterial thrombosis.

Thiols as a marker of inflammatory bowel disease activity: a systematic review

BACKGROUND

Evidence indicates that inflammation in Inflammatory Bowel Disease (IBD) is associated with increased systemic levels of reactive oxygen species. Systemic oxidative stress has been associated with reduced levels of plasma thiols. Less invasive tests capable of reflecting and predicting IBD activity are increasingly sought after. We sought to systematically review the evidence inherent in serum thiol levels as a marker of Crohn's Disease and Ulcerative Colitis activity (PROSPERO: CRD42021255521).

METHODS

The highest quality documents for systematic reviews standards were used as reference. Articles were searched on Medline via PubMed, VHL, LILACS, WOS, EMBASE, SCOPUS, COCHRANE, CINAHL, OVID, CTGOV, WHO/ICTRP, OPENGREY, BDTD and CAPES, between August, 03 and September, 03 on 2021. Descriptors were defined according to the Medical Subject Heading. Of the 11 articles selected for full reading, 8 were included in the review. It was not possible to perform a pooled analysis of the studies, as there were no combinable studies between subjects with active IBD and controls/inactive disease.

RESULTS

Findings from the individual studies included in this review suggest an association between disease activity and systemic oxidation, as measured by serum thiol levels, however, there are limitations that preclude weighting the study results in a meta-analysis.

CONCLUSIONS

We recommend conducting better-designed and controlled studies, that include individuals of both phenotypes and at different stages of IBD, involving a larger number of participants, using the standardization of the technique for measuring serum thiols, to confirm whether thiols can be a good parameter for monitoring the clinical course of these intestinal diseases and the degree of clinical applicability.

Ternary water-organic solvent mixtures used for insecticide SPE extraction and analysis with acetylcholinesterase biosensor

Few biosensors are reported for usage in combination with the organic solvent due to their negative impact on the enzymes. The usage of ternary water-organic solvent mixtures in combination with acetylcholinesterase biosensors allows to increase the useable total content of organic solvents with minimum negative effects to a higher content in comparison with a single organic solvent in water. The combination of acetonitrile/ethanol/water has a smaller negative effect on both enzyme activity and inhibition by insecticides in comparison with acetonitrile/methanol/water mixtures. The insecticides were eluted from solid-phase extraction (SPE) columns with a binary mixture of organic solvents acetonitrile/ethanol in 1/3 ratio and subsequently analysed with an acetylcholinesterase biosensor and the optimum total content of organic solvents of 12%. The analytical method allows the analysis of complex samples with improved selectivity and at improved limits of detection for chlorpyrifos-oxon and carbofuran analysis in river waters and soil samples. The usage of mixtures of organic solvents in combination with enzymes is an interesting approach that allows working with a higher total content of organic solvents than each individual solvent.

O-218 Single-cell RNA sequencing reveals that Ashermańs syndrome is caused by chronic inflammation that induces differential molecular and cellular cartography in the human endometrium

Study question

What is the differential cellular, transcriptomic and immunological differences of the human endometrium in AS versus healthy patients at single cell resolution?

Summary answer

The epithelial fraction is decreased, the myeloid and lymphoid cell lineages increased with an altered inflammation, inhibition of angiogenesis and EM abnormal remodeling.

What is known already

Asherman’s Syndrome (AS) is an acquired pathological condition, defined by the presence of intrauterine adhesions (IUAs) causing the uterine walls to adhere to one another resulting in menstrual abnormalities, pelvic pain, infertility, recurrent miscarriage, and abnormal placentation. However, the underlaying cellular, transcriptomic and immunological mechanisms at the single-cell level that occur in AS have not been investigated. 

Study design, size, duration

Single cell RNA-seq (scRNA-seq) was performed on 41,854 cells corresponding to endometrial biopsies from a total of 7 individuals with severe AS (AFS classification 1998). These patients were involved in a phase I/II, prospective, non-randomized, uncontrolled, multicenter, interventional clinical trial authorized by the Spanish Medicines Agency (AEMPS)(2016-003973-23). Control healthy endometrium was represented by 68,026 cell transcriptomes from our previous work (Wang et al. 2020). 

Participants/materials, setting, methods

Seven patients were included. Ultrasound and hysteroscopies were performed in mid secretory phase. Endometrial specimens were digested with collagenase and filtered. Epithelial cells were digested with trypsin and red blood cells removed. After MACS live enrichment, cells were loaded onto ChromiumNext GEM (10xGenomics). Libraries were sequenced in a Novaseq, and reads processed with CellRanger. Quality filtering, normalization, clustering and differential expression analysis were applied from ‘Seurat’ package. Functional enrichment analysis was computed using ‘escape’ package.

Main results and the role of chance

In total 109,880 cell transcriptomes were compared and found changes in cell population ratios in two specific cell types. First, the epithelial fraction was decreased in AS compared to healthy condition (26.53% vs 45.7%, respectively) specifically the epithelium representing the opening of the window of implantation (WOI) (0.25% vs 2.01%respectively), and the ciliated epithelium (0.84% vs 6.12%, respectively). Second, the myeloid and lymphoid cell lineages, which are much more abundant in AS samples. Macrophages (1.97% vs 0.24%, respectively), CD8+ T cells (3.71% vs 1.34%, respectively), and CD8- T cells (2.28% vs 0.55%, respectively).

In addition, there was a different transcriptomic composition represented by three differential linked clusters related to AS condition. First, a unique stromal cluster labelled as stromal_ACTA2 that express genes related to contractile functions (ACTA2, MYH11, DES). Second, a specific AS epithelium cluster closely related to antigen processing and presentation of HLA class II family genes. Third, a KRT8 ACTA2 cluster composed by genes related to collagen (COL3A1 and COL1A1) and IGFBP5.

Enrichment analysis performed with ssGSEA revealed the functional impact of the AS condition identifying an increase in different GO terms related to tissue damage, pro-inflammatory processes, inhibition of angiogenesis.

Limitations, reasons for caution

Despite these promising results, this is an study in progress to be completed with 10 patients 

Wider implications of the findings

These findings describe for the first time the pathophysiology of AS at single cell level with the functional involvement of inflammation, fibrosis, and defective angiogenesis in this pathological condition. 

Trial registration number

Eudra CT 2016-003975-23

APOL1 Renal Risk Variants and Kidney Function in HIV-1–Infected People From Sub-Saharan Africa

Introduction

APOL1 G1 and G2 alleles have been associated with kidney-related outcomes in people living with HIV (PLHIV) of Black African origin. No APOL1-related kidney risk data have yet been reported in PLHIV in West Africa, where high APOL1 allele frequencies have been observed.

Methods

We collected clinical data from PLHIV followed in Burkina Faso (N = 413) and in the ANRS-12169/2LADY trial (Cameroon, Senegal, Burkina Faso, N = 369). APOL1 G1 and G2 risk variants were genotyped using TaqMan assays, and APOL1 high-risk (HR) genotype was defined by the carriage of 2 risk alleles.

Results

In West Africa (Burkina Faso and Senegal), the G1 and G2 allele frequencies were 13.3% and 10.7%, respectively. In Cameroon (Central Africa), G1 and G2 frequencies were 8.7% and 8.9%, respectively. APOL1 HR prevalence was 4.9% in West Africa and 3.4% in Cameroon. We found no direct association between APOL1 HR and estimated glomerular filtration rate (eGFR) change over time. Nevertheless, among the 2LADY cohort participants, those with both APOL1 HR and high baseline viral load had a faster eGFR progression (β = −3.9[−7.7 to −0.1] ml/min per 1.73 m² per year, P < 0.05) than those with low-risk (LR) genotype and low viral load.

Conclusion

Overall, the APOL1 risk allele frequencies in PLHIV were higher in the West African countries than in Cameroon, but much lower than previously reported in some Nigeria ethnic groups, which strongly advocates for further investigation in the African continent. This study suggested that the virological status could modulate the APOL1 impact on kidney function, hence reinforcing the need for early therapeutic interventions.

Structure-Function Relationship of the Disintegrin Family: Sequence Signature and Integrin Interaction

Disintegrins are small cysteine-rich proteins found in a variety of snake venom. These proteins selectively modulate integrin function, heterodimeric receptors involved in cell-cell and cell-matrix interaction that are widely studied as therapeutic targets. Snake venom disintegrins emerged from the snake venom metalloproteinase and are classified according to the sequence size and number of disulfide bonds. Evolutive structure and function diversification of disintegrin family involves a stepwise decrease in the polypeptide chain, loss of cysteine residues, and selectivity. Since the structure elucidation of echistatin, the description of the structural properties of disintegrins has allowed the investigation of the mechanisms involved in integrin-cell-extracellular matrix interaction. This review provides an analysis of the structures of all family groups enabling the description of an expanded classification of the disintegrin family in seven groups. Each group presents a particular disulfide pattern and sequence signatures, facilitating the identification of new disintegrins. The classification was based on the disintegrin-like domain of the human metalloproteinase (ADAM-10). We also present the sequence and structural signatures important for disintegrin-integrin interaction, unveiling the relationship between the structure and function of these proteins.

Association of GSTM1 Deletion With Progression of CKD in Children: Findings From the Chronic Kidney Disease in Children (CKiD) Study

RATIONALE AND OBJECTIVE

Loss of function of the product of the GSTM1 gene has been implicated in rapid progression of adult CKD. Its role in pediatric CKD has not been previously described.

STUDY DESIGN

The study is a secondary analysis of a prospective observational cohort examining the association between deletions in GSTM1 and progression of CKD.

SETTING AND PARTICIPANTS

We used data and samples from the prospective Chronic Kidney Disease in Children (CKiD) cohort aged 1-16 years at enrollment with CKD.

EXPOSURE

We defined exposure fewer than two GSTM1 alleles on real-time polymerase chain reaction amplification.

OUTCOME

The primary outcome was a composite of 50% decrease in estimated glomerular filtration rate (eGFR) or start of kidney replacement therapy. Secondary outcomes included remission of proteinuria in children with glomerular disease and cardiovascular complications.

ANALYTIC APPROACH

The primary analysis was by Cox proportional hazards model. Analysis was adjusted for age, sex, race, ethnicity, BMI category, diagnosis category, and eGFR.

RESULTS

674 children were included in the analysis. Mean age at most recent visit was 11.9 years; 61% were male and 20% were Black. There were 241 occurrences of the primary outcome at the time of analysis. After adjustment for baseline characteristics, the risk of progression of CKD for exposed children was 1.94 (1.27, 2.97). The effect size was similar with either one or two deletions (autosomal dominant inheritance). The relationships between number of functional GSTM1 alleles and prespecified secondary outcomes were not statistically significant after adjustment.

LIMITATIONS

Missing data, especially for secondary outcomes, and relatively small sample size compared to genetic studies in adults.

CONCLUSIONS

GSTM1 deletion is associated with more rapid progression of pediatric CKD after adjustment in this large prospective cohort. No statistically significant associations were seen with secondary outcomes. If replicated, these findings may inform development of interventions for CKD in children.

Yeast interaction on Chardonnay wine composition: Impact of strain and inoculation time

It is of great importance to understand the molecular characteristics and substantial chemical transformations due to yeast-yeast interaction. Non-targeted metabolomics was used to unravel must in fermentation composition, inoculated with non-Saccharomyces (NS) yeasts and Saccharomyces cerevisiae (S) for sequential fermentation. ultrahigh-resolution mass spectrometry was able to distinguish thousands of metabolites and provides deep insights into grape must composition allowing better understanding of the yeast-yeast interactome. The dominance of S, characterized by a metabolic richness not found with NS, is dependent on inoculation time and on the yeast species present. Co-inoculation leads to the formation of new compounds, reflecting a reshuffling of yeast metabolism linked to interaction mechanisms. Among the modifications observed, metabolomic unravels deep changes in nitrogen metabolism due to yeast-yeast interactions and suggests that the redistribution pattern affects two different routes, the pentose phosphate and the amino acid synthesis pathways.

Review. Some People and Places Important in the History of Analytical Chemistry in Romania

Analytical chemistry developed from alchemical origins in the 14th century becoming more scientific in nature from the late 17th century and continues to thrive in modern Romania, as in the rest of Europe.

Effects of diclofenac on sentinel species and aquatic communities in semi-natural conditions

Due to the potential hazard of diclofenac on aquatic organisms and the lack of higher-tier ecotoxicological studies, a long-term freshwater mesocosm experiment was set up to study the effects of this substance on primary producers and consumers at environmentally realistic nominal concentrations 0.1, 1 and 10 µg/L (average effective concentrations 0.041, 0.44 and 3.82 µg/L). During the six-month exposure period, the biovolume of two macrophyte species (Nasturtium officinale and Callitriche platycarpa) significantly decreased at the highest treatment level. Subsequently, a decrease in dissolved oxygen levels was observed. High mortality rates, effects on immunity, and high genotoxicity were found for encaged zebra mussels (Dreissena polymorpha) in all treatments. In the highest treatment level, one month after the beginning of the exposure, mortality of adult fish (Gasterosteus aculeatus) caused effects on the final population structure. Total abundance of fish and the percentage of juveniles decreased whereas the percentage of adults increased. This led to an overall shift in the length frequency distribution of the F₁ generation compared to the control. Consequently, indirect effects on the community structure of zooplankton and macroinvertebrates were observed in the highest treatment level. The No Observed Effect Concentration (NOEC) value at the individual level was < 0.1 µg/L and 1 µg/L at the population and community levels. Our study showed that in more natural conditions, diclofenac could cause more severe effects compared to those observed in laboratory conditions. The use of our results for regulatory matters is also discussed.

Joint Associations of Maternal-Fetal APOL1 Genotypes and Maternal Country of Origin With Preeclampsia Risk

RATIONALE & OBJECTIVES

Preeclampsia, which disproportionately affects Black women, is a leading cause of preterm delivery and risk for future hypertension and chronic kidney disease (CKD). Apolipoprotein L1 (APOL1) kidney risk alleles, common among Black individuals, contribute substantially to CKD disparities. Given the strong link between preeclampsia and CKD, we investigated whether maternal and fetal APOL1 risk alleles can jointly influence preeclampsia risk, and explored potential modifiers of the association between APOL1 and preeclampsia.

STUDY DESIGN

Nested case-control study.

SETTING & PARTICIPANTS

426 Black mother-infant pairs (275 African Americans and 151 Haitians) from the Boston Birth Cohort.

EXPOSURE

Maternal and fetal APOL1 risk alleles.

OUTCOMES

Preeclampsia.

ANALYTICAL APPROACH

Logistic regression models with adjustment for demographic characteristics were applied to analyze associations between fetal and maternal APOL1 risk alleles and risk of preeclampsia and to investigate the effects of modification by maternal country of origin.

RESULTS

Fetal APOL1 risk alleles tended to be associated with an increased risk of preeclampsia, which was not statistically significant in the total genotyped population. However, this association was modified by maternal country of origin (P<0.05 for interaction tests): fetal APOL1 risk alleles were significantly associated with an increased risk of preeclampsia among African Americans under recessive (odds ratio [OR], 3.6 [95% CI, 1.3-9.7]; P=0.01) and additive (OR, 1.7 [95% CI, 1.1-2.6]; P=0.01) genetic models but not in Haitian Americans. Also, maternal-fetal genotype discordance at the APOL1 locus was associated with a 2.6-fold higher risk of preeclampsia (P<0.001) in African Americans.

LIMITATIONS

Limited sample size in stratified analyses; self-reported maternal country of origin; pre-pregnancy estimated glomerular filtration rate (eGFR) and proteinuria data in mothers were not collected; unmeasured confounding social and/or environmental factors; no replication study.

CONCLUSIONS

This study supports the hypothesis that fetal APOL1 kidney risk alleles are associated with increased risk for preeclampsia in a recessive mode of inheritance in African Americans and suggests that maternal-fetal genotype discordance is also associated with this risk. These conclusions underscore the need to better understand maternal-fetal interaction and their genetic and environmental factors as contributors to ethnic disparities in preeclampsia.

Derivatization procedures and their analytical performances for HPLC determination in bioanalysis

Derivatization, or chemical structure modification, is often used in bioanalysis performed by liquid chromatography technique in order to enhance detectability or to improve the chromatographic performance for the target analytes. The derivatization process is discussed according to the analytical procedure used to achieve the reaction between the reagent and the target compounds (containing hydroxyl, thiol, amino, carbonyl and carboxyl as the main functional groups involved in derivatization). Important procedures for derivatization used in bioanalysis are in situ or based on extraction processes (liquid-liquid, solid-phase and related techniques) applied to the biomatrix. In the review, chiral, isotope-labeling, hydrophobicity-tailored and post-column derivatizations are also included, based on representative publications in the literature during the last two decades. Examples of derivatization reagents and brief reaction conditions are included, together with some bioanalytical applications and performances (chromatographic conditions, detection limit, stability and sample biomatrix).

One year prospective survey of azole resistance in Aspergillus fumigatus at a French cystic fibrosis reference centre: prevalence and mechanisms of resistance

BACKGROUND

Studies on Aspergillus fumigatus azole resistance in cystic fibrosis patients are scarce despite the fact that it is the most frequently isolated fungus from respiratory samples from these individuals.

OBJECTIVES

To evaluate resistance prevalence, investigate mechanisms of resistance and explore the relationship between resistant isolates by genotyping.

METHODS

We conducted a prospective 1 year study (from 1 January to 31 December 2015), based on the investigation of up to five colonies per sample from cystic fibrosis patients.

RESULTS

Twenty-three (6.5%) isolates among the 355 tested were resistant to at least one triazole drug, using the EUCAST reference method, leading to a prevalence of 6.8% (6/88 patients). Analysis of resistance mechanisms highlighted TR34/L98H (n = 10), TR46/Y121F/T289A (n = 1), WT cyp51A (n = 11) and F46Y/M172V/N248T/D255E/E427K (n = 1). No genotype was shared between patients.

CONCLUSIONS

This study showed a relatively stable resistance prevalence in comparison with the previous study conducted in 2010-11 (8%), although resistance mechanisms varied between the two studies.

Does phase ratio in reversed phase high performance liquid chromatography vary with temperature?

Phase ratio Φ for an high performance liquid chromatography (HPLC) column is a parameter defined as the ratio between the volume of the stationary phase V_s and the void volume of the column V_m. Together with the equilibrium constant K of the separation process, phase ratio is part of the retention factor k (k = KΦ). Although a considerable number of studies have been dedicated to the evaluation of V_s and V_m with the goal of obtaining the value for Φ, there are still debatable results regarding the true value of Φ, which for a column with a specific stationary phase may vary with the composition of the mobile phase. One route for the evaluation of the value of Φ uses the measurements of retention factors k on a specific column and mobile phase for two or more hydrocarbons for which the octanol/water partition coefficients log K_ow are known. This procedure has been applied in the present study for the evaluation of Φ for three commercially available C18 columns and two mobile phase compositions water/acetonitrile, in the temperature range 20 °C to 50 °C. It was found that phase ratio does change depending on the temperature, its "effective value" decreasing as the temperature increases which is in accordance with the decrease of retention times in reversed phase HPLC when the temperature increases. Besides other factors that may affect the correct calculation of thermodynamic functions, the change of phase ratio with temperature has implications regarding the possibility to calculate the enthalpy and entropy values from van't Hoff plots of the variation of log k as a function of 1/T, even when the retention process is dominated by unique hydrophobic type interactions.

Conceptualization of an ICU Infrastructure for Simulation Based Education in Medical Engineering & eHealth

The use of simulation-based training is gaining importance in medical as well as engineering related education. The complex environment of an intensive care unit is characterized by a high need of interaction between clinical as well as technical components and views. These diverse interactions and the connected requirements are the focus for the presented simulation infrastructure, enabling research, education and training. The presented concept of a modular and flexible intensive care environment provides a high degree of interoperability and flexibility for individual research questions and full support of connectivity for typical clinical workflows. The presented simulation and testing bed will allow both, education for engineering and medical students using patient simulation and simultaneous data transfer as well as research on medical workflows, infrastructural demands and connectivity conformance questions.

Sources of Nonlinear van't Hoff Temperature Dependence in High-Performance Liquid Chromatography

In HPLC, the nonlinear behavior of the retention factor k' with temperature (dependence of ln k' on 1/T) can be attributed to the multiple interactions of a unique analyte in the separation process and/or to the existence in solution of multiple forms of the analyte (also leading to different free enthalpies of interaction). In this study, several examples of nonlinear retention-temperature dependence are evaluated for both reversed-phase (RP) and hydrophilic interaction chromatography (HILIC) separations. The potential explanation for nonlinear retention-temperature behavior is evaluated for each example, some caused by multiple interactions in the separation system of a unique analyte and others by multiple forms of the analyte. In cases where the analyte does not have more forms and the separation is based predominantly on one type of interaction (e.g., hydrophobic interaction in RP-HPLC), the dependence is linear, as expected. By studying the changes in the chemical structure of a compound as a function of pH it is possible to decide, in many cases, if a unique form or multiple forms of a compound are present in the solution. The use of this information allows us to determine when the lack of linearity (when present) is caused by multiple interactions in the separation system (for one form of the compound) and when more forms are causing the lack of linearity. The approximation with a quadratic form for the nonlinear dependence has been verified in most cases to be good, and only minor improvements were obtained when using higher polynomial dependencies.

[Quality criteria for the transition to adult care in French CF centers - results from the SAFETIM APP study?]

INTRODUCTION

SAFETIM-APP compiled an inventory of professional practice in the 45 French cystic fibrosis reference centres (CFRC), between February 2015 and December 2016, related to the transition of adolescents with cystic fibrosis to adult centres.

METHOD

This multicentre cross-sectional study addressed the modalities of the transition in CFRCs and proposed a list of items that could be used to establish quality criteria. Quantitative analysis of the criteria and a qualitative analysis of the transition procedure were carried out.

RESULTS

A total of 77% of the CFRCs that were contacted took part. Transition lasted 3 to 5 years and began at around 15 years of age. Nine criteria were described as fundamental, including: collaboration between teams, taking adolescence into account, having a time for adolescents to speak with the physician alone, defining a program including therapeutic education, involving the family, accompanying the parents. Seven additional criteria were noted to be important, including: re-announcing the diagnosis, identifying a common thread (caregiver) accompanying the family, scheduling adult follow-up from paediatrics onwards, visiting the adult department, organizing a formal departure/reception time, initiating the process early enough, identifying indicators to evaluate practices.

CONCLUSION

The transition processes in place in CFRCs can be improved by implementing the use of these quality criteria systematically.

Recombinant and Chimeric Disintegrins in Preclinical Research

Disintegrins are a family of small cysteine-rich peptides, found in a wide variety of snake venoms of different phylogenetic origin. These peptides selectively bind to integrins, which are heterodimeric adhesion receptors that play a fundamental role in the regulation of many physiological and pathological processes, such as hemostasis and tumor metastasis. Most disintegrins interact with integrins through the RGD (Arg-Gly-Asp) sequence loop, resulting in an active site that modulates the integrin activity. Some variations in the tripeptide sequence and the variability in its neighborhood result in a different specificity or affinity toward integrin receptors from platelets, tumor cells or neutrophils. Recombinant forms of these proteins are obtained mainly through Escherichia coli, which is the most common host used for heterologous expression. Advances in the study of the structure-activity relationship and importance of some regions of the molecule, especially the hairpin loop and the C-terminus, rely on approaches such as site-directed mutagenesis and the design and expression of chimeric peptides. This review provides highlights of the biological relevance and contribution of recombinant disintegrins to the understanding of their binding specificity, biological activities and therapeutic potential. The biological and pharmacological relevance on the newest discoveries about this family of integrin-binding proteins are discussed.

Clinical Use of an Imaging Probe in Breast Cancer Surgery

Aim

Portable cameras allow easy transfer of the detector, and thus of radioisotope imaging, to the operating room. In this paper we describe our preliminary experience in radionuclide imaging of breast cancer with a 22.8 × 22.8 mm2 field-of-view minicamera called “Imaging Probe” (IP).

Methods

Breast cancer detection by IP was performed to guide biopsy, in particular open biopsy, or help fine-needle or core-needle positioning when the main guidance method was ultrasonography or digital radiography. 99mTc Sestamibi (MIBI) was injected 1 h before imaging and biopsy to 14 patients with suspected or known breast cancer. Scintigraphic images were acquired before and after biopsy in each patient. The surgeon was allowed to take into account scintigraphic images as well as previously performed mammograms and ultrasonography.

Results

High-resolution IP images were able to guide biopsy toward cancer or toward washout zones of cancer, which are thought to be chemoresistant, in seven patients out of 10. Four patients in whom IP and MIBI were unable to guide biopsy were found not to have cancer.

Conclusions

Our study confirms the ability of IP to guide breast biopsy even when our minicamera has to be handled manually by trained physicians during surgery.

New Localization Technique for Breast Cancer Biopsy: Mammotome Guidance with Imaging Probe

Aims and Background

The “Imaging probe” (IP) is a small, portable, high-resolution gamma camera to be used in radioguided surgery. The present work discusses a special prototype designed for guiding biopsies. The IP was mounted to a Fischer digital X-ray stereotactic core biopsy system in such a way that biopsy could be guided simultaneously by X-ray stereotaxis and 99mTc-Sestamibi (MIBI) images from IP.

Methods

The IP field of view was 22.8 × 22.8 mm2, with a spatial resolution of approx. 2.5 mm. We used off-line software for image fusion on a dedicated Pentium III portable PC. It was matched with a Fischer digital X-ray stereotactic biopsy system dedicated to direct the mammotome towards breast opacities. The operator was allowed to slightly correct the direction of the mammotome needle taking into account stereotactic X-ray, scintigraphic and fused images. Biopsy samples were counted by IP before they were sent to the pathologist.

Results

High-resolution IP scintigraphy showed substantial, though not exact, matching between MIBI hot spots and X-ray opacities. More than one hot spot was detected even in the smallest (0.6 cm) lesion. Post-biopsy scintigraphy showed absence of significant hot spots in two patients, whereas in the third patient one of the three hot spots was still partially present. All lesions showed cancer on histological examination.

Conclusions

Measurement of radioactivity in biopsy specimens confirmed the heterogeneous distribution of radioactivity within cancers that IP had detected before biopsy.

Sentinel Node Detection with Imaging Probe

A one-square-inch-field-of-view mini gamma camera, whose first prototype was built by us in 1998 and given the name imaging probe (IP), was initially employed in sentinel lymph node (SLN) detection. This is probably the best way of learning how to use it. In the present work IP was used for SLN localization by a medical team that, after having been trained by the group of nuclear physicians of “La Sapienza” University who designed and first used the detector, used IP at their own hospital to 1) acquire experience for future use during surgery (a cooperative project on IP-radioguided orthopedic surgery is ongoing) and 2) start multicenter trials with IP. The SLN was identified and localized with IP and a non-imaging probe, Neoprobe 2000, in six patients with breast cancer who underwent lymphoscintigraphy for SLN biopsy. The operators who used Neoprobe and IP were blinded to each other's findings and to the results obtained with the large-field-of-view Anger camera that was used for lymphoscintigraphy. The Anger camera, IP and Neoprobe detected seven SLNs in six patients. The mean detection time was 2 mins 6 s (standard deviation (SD) 26 s) with IP, and 2 mins 18 s (SD 47 s) with Neoprobe 2000. The SLN that was most difficult to find was detected in 2 mins 56 s with IP and 3 mins 45 s with Neoprobe. The operators' subjective impression of having detected the SLN was “absolutely sure” for 7/7 nodes with IP and “absolutely sure” for 5/7 nodes with Neoprobe.

Detection of Sentinel Node in Breast Cancer: Pilot Study with the Imaging Probe

The commonly used gamma probes are easy to use but also give rough information when employed in radioisotope-guided surgery. When images are required for exact localization, a gamma camera as well as a probe have to be used. Position-sensitive photomultipliers have contemporaneously allowed high-resolution scintigraphy and miniaturization of gamma cameras. We have assembled a miniature gamma camera with a 1-square-inch field of view and an intrinsic resolution of about 1 mm. When the minicamera is collimated with a large-holed, highly sensitive collimator, it acquires a spatial resolution of 3 mm. This prototype has been tested in the detection of difficult-to-image breast cancer sentinel nodes. Five nodes that had not been found with the usual technique of an Anger camera plus conventional probe were checked with the miniature camera that we named imaging probe: it actually is small enough to be used as a probe and large enough to give an image. One of the five nodes was found and imaged. It was small, disease-free, close to the tumor and probably hidden by the Compton halo around the peritumoral injection site. Our pilot study shows that the imaging probe, although still a prototype, has certain advantages over conventional methods when lymph node localization is required during surgery.

Evaluating wearable multimodal sensor insoles for motion-pattern measurements in stroke rehabilitation - A pilot study

The majority of stroke patients experience deficits in motoric functions, especially in gait and mobility. They need rehabilitation to regain walking independence, which is a major goal of rehabilitation after stroke. To document and assess the rehabilitation progress, instrumented motion analysis and clinical assessments are commonly used. In a clinical pilot study the applicability of an instrumented insole system in stroke rehabilitation is evaluated. Motion parameter of 35 stroke patients were gathered with the system while completing 90 s level walking and Timed Up & Go test at the beginning and end of four weeks inpatient rehabilitation. For level walking the motion parameter were gathered with the clinical reference system simultaneously. The mean stride time for level walking decreased from 1.20 s to 1.16 s (clinical system), or from 1.19 s to 1.12 s (insole system), respectively. Focusing on individual comparison of each patient's progress, 9 gait parameters are extracted for level walking, 6 sub-phases of Timed Up & Go test are detected and analyzed, as well as progress of Center of Pressure in the sub-phases is examined. Although the overall data show wide distribution, the system proofed to be applicable in clinical stroke rehabilitation routine. As the system is location-independent, and has the advantage of assessing additional parameters of the Timed Up & Go test, it is additionally suitable for integration in a tele-or home rehabilitation system.

Efficacy and safety of a new coverlet device on skin microclimate management: a pilot study in critical care patients

OBJECTIVE

To test the effect of a new coverlet device, allowing air circulation at the body/underlying surface interface, on skin microclimate management.

METHOD

This prospective observational pilot study took place in a 15-bed university-affiliated intensive care unit. Overall, 34 mechanically ventilated patients were included. Skin humidity and temperature were monitored before and after the implementation of the tested device at the occiput, scapulas, buttocks and sacrum. Humidity and temperature were evaluated through surface skin impedance and an infra-red thermometer, respectively. Health professionals were asked to evaluate the device.

RESULTS

After implementation of the coverlet device, there was a rapid, sustained and significant decrease in skin humidity at all sites ranging from 6 % to 15 %, excluding the occiput. Skin temperature also significantly decreased from 1 % at both scapulas, but not at the other studied body sites. No side effects were observed. Health professionals reported that the device was easy and quick to install. Although they did not report a subjective improvement in skin moisture or temperature, they considered the device to be efficient.

CONCLUSION

Although limited by its design, this pilot study suggests a good efficacy of the studied device on skin microclimate management. Further data are warranted to test the clinical implications of our findings.

[Comparison of diagnostic quality in hysterosalpingography between iodinated non-ionic contrast media with low and high osmolarity]

PURPOSE

Comparison of diagnostic quality in hysterosalpingography between low and high-osmolality contrast media.

MATERIALS AND METHODS

We performed a retrospective evaluation of two cohorts of patients who underwent HSG using contrast media with different osmolarity: the first group ,47 patients, underwent hysterosalpingography in the period September 2011-December 2012 using Iopromide 370 mg/ml; the second group, 50 patients, underwent HSG from January 2013 to October 2013 using Iomeprol 400 mg/ml. Three radiologists, in consensus reading,, reviewed the radiographs by assessing the following four parameters: opacification of the uterine cavity, uterine profiles definition, Fallopian tubes visualization, contrast media spillage into peritoneum. A score-scale from 0 to 3 was assigned for each of the mentioned parameter (0 = minimum non-diagnostic exam, 1 = sufficient examination; 2 = good quality examination; maximum 3 = high quality images).

RESULTS

We documented a statistically significant higher quality in displaying Fallopian tubes among patients studied through high osmolarity contrast medium (Iopromide 370 mg/ml) than what obtained through lower osmolarity contrast medium (Iomeprol 400 mg/ml).

CONCLUSIONS

The use of high osmolarity contrast medium enabled better visualization of the tubes and a greater number of diagnoses of chronic aspecific salpigintis due to the increased osmolality and viscosity of Iomeprol 400 mg/ml. There were no significant differences between the two contrast agents in the evaluation of intra-uterine pathology and in the evaluation of the tubal patency.

[Necrotizing Fasciitis: A comprehensive review]

Even though necrotizing fasciitis is considered a rare disease, the spreading of the predisposing factors such as diabetes and chronic diseases, contribute to increase the incidence of this infection. Thus, how to diagnose and treat this clinical pathology, which represents an emerging need. This infection could be fatal for patients if not early diagnosed and treated and it represents a challenge both for the clinicians both for the surgeons. From this consideration was born the idea to write this review article in order to furnish to the readers a helpful tool in the management of this disease starting from its clinical and epidemiological features leading to the diagnosis, both clinical and radiological, and concluding with the treatment both medical both surgical .This article reviews literature on PubMed/MEDLINE with key words "necrotizing", "fasciitis" and "necrotizing fasciitis" from 1967 to 2014, considering all the aspects of the disease. The authors attempt to draw comparisons to their own experience managing this condition to give an Italian perspective to the condition.