P-411 Blood concentrations of specific (PCBs) congeners and abortion rates in healthy women undergoing IVF cycles living in areas with high and low pollution. (EcoFoodFertility Project)

Study question

Human exposure to polychlorinated biphenyls (PCBs) exists despite its ceased production since 1977. PCBs congeners harm reproductive health, but data remain inconclusive.

Summary answer

Evaluate relationship between blood concentrations of specific (PCBs) congeners and abortion rates in women undergoing IVF cycles living in areas with high and low pollution.

What is known already

PCBs are a class of synthetic chemicals that were widely used in industry until the 1970s and are found in many consumer products as refrigerants in electrical equipment, as flame retardants in plastics production and electronics. Continuous exposure to PCBs is of concern because they fall into the group of endocrine disruptors (EDCs), PCB congeners can spread throughout the female reproductive tract. Indeed, they have been found in human follicle fluids, placenta, amniotic fluid in embryos and fetuses Despite multiple reproductive health effects in women was reported, the results are sometimes inconsistent between experimental and epidemiological studies.

Study design, size, duration

In the frame of EcoFoodFertility Project, a cross sectional study conducted in Campania Region (Italy) to assess environmental impact on fertility and human health, blood samples were collected during the IVF cycles of the 65 women (aged 27.8 + 3.6) no smokers, BMI 23.5 – 27.9, normal menstruation, in two areas with high and low pollution between 2017 and 2019. The PCBs congeners we investigated were: estrogenic congeners (31,44,52,101,153), anti-estrogenic congeners (77,105,110,114,126,156,169) and other (28,118,138,180).

Participants/materials, setting, methods

Group A (n = 30) living in low polluted area (LPA), alto Medio Sele in province of Salerno, and group B (n = 35) living in highly polluted area (HPA), known as the “Land of Fires” due to the many sources of pollution. The blood sample was taken on the day of the oocyte pick-up and PCBs were measured by Gas Chromatography Coupled to (tandem) Mass Spectrometry. Statistical analyses were performed by GraphPad Prism 9.

Main results and the role of chance

Blood concentrations of PCBs are expressed as wet weight (nanograms per gram of serum) and as standardised lipid concentrations (nanograms per gram lipid). The PCB 169 congener was found in the highest concentration, 229.62 ng/g and, on average, accounted for 46.2 % of ΣPCBs tested. The PCB 77 (p < 0.05) and 118 ((p < 0.001) congeners were significantly higher in participants permanently living in HPA (Group B). For the other congeners, no significant variation was found. No significant variations between the two groups for oocyte pick-up rate, metaphase I and II oocyte ratio was found, fertilisation rate and pregnancy rate. Furthermore, the probability of embryo implantation was similar between the two groups, but the abortion rate was 3.0 times higher in group B. The probability of live births is 85.7% in group A and 53.85% in group B.These findings, even if the results between PCBs exposure and reproductive outcomes are due to the different congeners of these chemical compounds and unknown confounding factors and exposure times may be implicated, however suggest an association between the detection of specific PCB congeners and increased abortion rates in women undergoing IVF cycles that cannot be understimated.

Limitations, reasons for caution

Although we have set up a strict control and survey protocol, our study also has limitations due to the relatively small sample size of the groups and as with almost all epidemiological studies on environmental impact, there may be confounders or co-exposures that could interfere with the observed associations.

Wider implications of the findings

Although PCBs are no longer produced, the exposure remains widespread due to their long biological half-life, accumulation in the food chain and human health impacts are still reported. Our findings confirm these concerns, therefore, the study of these old chemicals is still relevant and important and should be expanded.

Trial registration number

not applicable

O-286 Bisphenol A in blood serum and follicular fluid of women undergoing to cycle of IVF living in areas with different environmental impact. (EcoFoodFertility Project)

Study question

Bisphenol A (BPA) is a constituent of polycarbonate and epoxy resin plastics and is also a by-product of combustion of plastics, resulting harmful for health.

Summary answer

To evaluate the presence of BPA in the blood and Follicular Fluids, in women, subjected to IVF cycles, living in areas with different environmental impact.

What is known already

BPA is used in the production of polycarbonate plastics and epoxy resins. 1,3,5-triphenylbenzene is a tracer for burning plastic and has been related to levels of bisphenol A in the air, so the actual release of bisphenol A to the atmosphere could result from burning the plastic. Bisphenol A belongs to the group of endocrine disruptors.

Little is known about the effects of BPA on human female reproduction. BPA levels appear to be inversely related to the number of oocytes retrieved in IVF cycles, and it also appears to negatively affect the ovulatory peak of estradiol.

Study design, size, duration

In the frame of EcoFoodFertility project a cross sectional study conducted in Campania Region (Southern Italy), between January 2019 and December 2020, 74 women, no smokers, no chronic diseases, not exposed to occupational risk factors. living for at least 5 years in areas with low environmental impact (LEI, 31 women), Alto-Medio Sele in province of Salerno and high environmental impact (HEI, 43 women), so-called “Land of Fires” in province of Naples, were selected.

Participants/materials, setting, methods

Participants have a normal ovarian reserve, average age 32.05 + 3.49, with infertility duration between 26 and 39 months and at the first experience of an IVF cycle. ELISA was used for measuring bisphenol A in blood and Follicular Fluids (FFs), expressed in ng/ mL. 5 mL glass tubes, without additives, not siliconized and kept in a horizontal position were used. FFs were bloodless with a negative albumin test.

Main results and the role of chance

Differents levels of BPA were found in all processed samples.

In the LEI (Low Environmental Impact) group, serum levels vary from a minimum of 3.1 ng/mL to a maximum of 7.7 ng/mL (4.1 ± 1.6) and the Follicular Fluids levels vary from a minimum of 7,1 ng/mL to a maximum of 55.3 ng/mL (13.8 ± 10.9).

In the HEI (High Environmental Impact) group, serum levels vary from a minimum of 69.2 ng/mL to a maximum of 167.8 ng/mL (95.5 ± 24.3) and Follicular Fluids levels vary from a minimum of 4.2 ng/mL to a maximum of 34.3 ng/mL (19.9 ± 9.2).

Statistical processing of the data shows a highly significant variation in serum levels (p < 0.0001) with higher values in the HEI group (95.5 ± 24.3) than in the LEI group (4.1 ± 1.6).

A moderately significant change (p < 0.01) for Follicular Fluids levels, higher in the HEI group (19.9 ± 9.2) than in the LEI group (13.8 ± 10.9).

Furthermore, the data did not show any correspondence between serum and Follicular Fluids for any of the participants tested.

Limitations, reasons for caution

The ELISA method for the determination of BPA seems suitable to us, however, the subject requires further biomonitoring studies, with a larger sample and greater selection of participants, to better understand the effects of BPA and its metabolites in FF and in other districts of the female reproductive system.

Wider implications of the findings

The results indicate that the greater bioaccumulation in women of the HEI group appears consistent with the environmental condition of the area and with the comparative studies already carried out within the EcoFoodFertility project. This is further evidence that pollution in this area can interfere with female fertility and beyond.

Trial registration number

G003

DEVELOPING INTEGRAL PROJECTION MODELS FOR ECOTOXICOLOGY

In many ecosystems, especially aquatic ecosystems, size plays a critical role in the factors that determine an individual's ability to survive and reproduce. In aquatic ecotoxicology, size informs both realized and potential acute and chronic effects of chemical exposure. This paper demonstrates how chemical and nonchemical effects on growth, survival, and reproduction can be linked to population-level dynamics using size-structured integral projection models (IPM). The modeling approach was developed with the goals and constraints of ecological risk assessors in mind, who are tasked with estimating the effects of chemical exposures to wildlife populations in a data-limited environment. The included case study is a collection of daily time-step IPMs parameterized for the life history and annual cycle of fathead minnows (Pimephales promelas), which motivated the development of modeling techniques for seasonal, iteroparous reproduction, density dependent growth effects, and size-dependent over-winter survival. The effects of a time-variable annual chemical exposure were interpreted using a toxicokinetic-toxicodynamic model for acute survival and sub-lethal growth effects model for chronic effects and incorporated into the IPMs. This paper presents a first application of integral projection models to ecotoxicology. Our research demonstrates that size-structured IPMs provide a promising, flexible, framework for synthesizing ecotoxicologically relevant data and theory to explore the effects of chemical and nonchemical stressors and the resulting impacts on exposed populations.

OP0042 BLOCKING OF CD103+ TISSUE RESIDENT MEMORY T CELLS (TRM) AS A THERAPEUTIC STRATEGY IN SJOGREN’S SYNDROME

Background:

Tissue-resident memory T cells (TRM), are a recently identified T cells population featuring tissue localization and expression of markers of tissue homing, CD69 and CD103. Recently, the expansion of CD8+ TRMs and their involvement in the sialadenitis was described in a murine model of SS. However, CD4+ and CD8+ TRM’s functional relevance in pSS is still not fully understood, and the TRM therapeutic targeting unexplored.

Objectives:

The study aimed to address the role of CD4+ and CD8+ TRMs in the pathogenesis of pSS and to explore the therapeutic targeting of the tissue residency marker of TRM CD103.

Methods:

An animal model of experimental (ESS) obtained by immunization of female C57BL/6 mice (n=10) with salivary glands (SG) protein extract and Freund’s complete adjuvant used to investigate the dynamic of infiltration of SG by CD4+ and CD8+ TRMs, their frequency, and the impact of CD103 blockade. For the therapeutic intervention, at 10-weeks post-immunization, the salivary gland was cannulated via Wharton’s duct, and an anti-CD103 neutralizing antibody or vehicle-injected. The mice’s saliva flow rate was assessed, and SGs were analyzed by Flow-cytometry and immunohistochemistry (IHC).

The frequency and localization of TRMs was analyzed in minor SG of sicca syndrome (nSS) and pSS patients (n=39) by flow cytometry and IHC. The expression of genes involved in the tissue retention of TRMs was assessed in SG by RT-PCR.

Results:

Upon the ESS progression, a significant progressive increase in CD45+CD103+ cells frequency was observed from 5wk to 20wk post-immunization (p<0.001), where the CD8+ were the most abundant, followed by CD4+. Consistently, CD103+CD8+ T cells were detected within the lymphocytic infiltration of SG from ESS mice. Sorted purified SG CD10+CD3+CD8+ T cells showed higher Granzyme B, TNF-alpha expression compared to CD103-CD3+CD8+ at both mRNA and protein levels. Notably, ESS mice treated with anti-CD103 showed improvement in salivary function (p<0.05) and reduced lymphocytic infiltrations measured as focus score (FS) (p<0.01) and area-fraction (p<0.01). Consistently, anti-CD103 treatment consistently reduced CD103+ cells and IFN-gamma+, Granzyme B+, and TNFa+ CD8+ cells. We next performed phenotypic analysis of CD45+CD103+ immune cells in the SG of pSS patients observing an increase in both with CD8+CD103+CD69+ and CD4+CD103+CD69+ (p<0.05). Finally, IHC showed that the expansion of TRMs in pSS salivary glands was accompanied by a down-regulation of E-cadherin glandular expression and their migration outside the epithelium in the context of inflammatory infiltrates. SG of patients with pSS showed a significant up-regulation of BLIMP1, KFL-2, and S1PR1 and down-regulation of ITGB2. CXCL9 and CXCL10, and IL-15 involved in the tissue recruitment and long-term survival of TRMs were significantly modulated in pSS salivary glands.

Conclusion:

TRM are expanded and activated in the SG of pSS and ESS, participating in the organization of tissue inflammation. Although the mechanisms behind this expansion are still not fully understood, CD103 could be a valuable novel therapeutic target to prevent lymphocytic infiltrations and glandular destruction in Sjogren syndrome.

Disclosure of Interests:

None declared

Recurrent hepatocellular carcinoma and non-classic adreno-genital syndrome

OBJECTIVE

Hepatocellular carcinoma (HCC) is one of the most common fatal cancer in the world and androgens are among the possible etiological factors. Congenital adrenal hyperplasia (CAH) is a group of inherited diseases caused by enzyme failure in the steroid biosynthesis of the adrenal cortex, resulting in an augmented 17-hydroxyprogesterone, androstenedione and testosterone production. While the occurrence of testicular adrenal rest tumors and adrenocortical tumors in congenital adrenal hyperplasia is well described in the literature, no data on HCC occurrence are available.

CASE PRESENTATION

A 35-years-old Italian man of Caucasian origin, affected by non-classic CAH due to partial 21-hydroxylase deficiency came to observation for revaluation of his adrenal picture. Besides common hormonal and biochemical analysis, an abdomen Magnetic Resonance Imaging was performed, resulting in an 18 mm large nodular lesion between liver segments VII and VIII. Radiological reports matched with an increased serum α-fetoprotein level. A surgical removal of the lesion was performed. After that, several recurrences of the lesion, which was consequently treated by radiofrequency ablation, occurred. Every recurrence was accompanied by an increase in testosterone and steroid hormone binding globulin serum levels.

CONCLUSIONS

Our report suggests the need for screening of liver lesions in males affected by this syndrome.

Elevated pCO2 and Hypoxia Alter the Acid-Base Homeostasis of Developing Sheepshead Minnows, Cyprinodon variegatus

Low dissolved oxygen and increased acidification are two environmental variables that concomitantly change in an estuarine environment, both of which are exacerbated by nutrient pollution and subsequent eutrophication. To better understand how estuarine residents compensate for daily fluctuations in these environmental variables, the interactive effects of acidification and hypoxia were assessed in developing sheepshead minnows (Cyprinodon variegatus) using a 2 by 2 factorial design over a 42-day exposure. Embryos were exposed to either acidic (partial pressure of CO₂, pCO₂, ~2000 μatm), hypoxic (reduced dissolved oxygen, ~2 mg l^-1), or combined acidic and hypoxic conditions and monitored for development, hatch rate, and survival. Changes in oxygen consumption, anaerobic metabolism, oxidative stress, and acid-base balance were evaluated at three life stages (embryo, larval, and juvenile fish) to discern if and how fish compensate for these stressors during development. The combination of acidification and hypoxia delayed hatching in embryos and significantly decreased oxygen consumption (p<0.001) in all three life-stages. Neither acidification, hypoxia, nor the combination of the stressors impacted the anaerobic metabolism or oxidative stress of juvenile fish, but acid-base equilibrium was disrupted by all three treatments in larval fish. Elevated carbonic anhydrase activity was observed in the multi-stress treatment in embryos and larval fish, but not in juvenile fish. These results show that developing sheepshead minnows can re-establish cellular homeostasis in compensating to acidified and hypoxic waters.

Thyroid Function and its Implications in Oxidative Stress Influencing the Pathogenesis of Osteoporosis in Adults with Down Syndrome: A Cohort Study

People with Down syndrome (DS) show lower bone mass density (BMD) and a higher prevalence of hypothyroidism compared to general population. Furthermore, DS is a well-known high oxidative stress (OS) condition because genes involved in OS map on chromosome 21. Thyroid function too is involved in OS. Since both thyroid function and OS lead to lower BMD and osteoporotic fractures, we have explored correlations among BMD, thyroid hormones, and parameters of OS in DS adults. A total of 105 DS patients (48 males; 21-71 years; mean BMI 28.88±7.12 kg/m(2)) were enrolled in a cohort study, 48 of them undergoing thyroid replacement therapy. We evaluated thyroid function, BMD, and total antioxidant capacity (TAC) in blood plasma. TAC was assayed by H2O2-metmyoglobin system, as source of radicals, and by the chromogenous ABTS, with a latency time (LAG) in the appearance of its cation ABTS+proportional to antioxidant concentration. BMD was evaluated with DEXA, using WHO criteria to classify osteoporosis. Low BMD was found in 83.78% of patients. TSH and LAG did not correlate with BMD. Nevertheless, LAG significantly correlates to Z-scores estimated at the lumbar spine (r(2)=0.558; p=0.03) in hypothyroid patients. Our data show that low TAC could be more associated with reduced BMD rather than TSH itself in DS patients and that the OS could have a role in the pathogenesis of osteoporosis regarding the hypothyroid subgroup.

Chitosan crosslinked flat scaffolds for peripheral nerve regeneration

Chitosan (CS) has been widely used in a variety of biomedical applications, including peripheral nerve repair, due to its excellent biocompatibility, biodegradability, readily availability and antibacterial activity. In this study, CS flat membranes, crosslinked with dibasic sodium phosphate (DSP) alone (CS/DSP) or in association with the γ-glycidoxypropyltrimethoxysilane (CS/GPTMS_DSP), were fabricated with a solvent casting technique. The constituent ratio of crosslinking agents and CS were previously selected to obtain a composite material having both adequate mechanical properties and high biocompatibility. In vitro cytotoxicity tests showed that both CS membranes allowed cell survival and proliferation. Moreover, CS/GPTMS_DSP membranes promoted cell adhesion, induced Schwann cell-like morphology and supported neurite outgrowth from dorsal root ganglia explants. Preliminary in vivo tests carried out on both types of nerve scaffolds (CS/DSP and CS/GPTMS_DSP membranes) demonstrated their potential for: (i) protecting, as a membrane, the site of nerve crush or repair by end-to-end surgery and avoiding post-operative nerve adhesion; (ii) bridging, as a conduit, the two nerve stumps after a severe peripheral nerve lesion with substance loss. A 1 cm gap on rat median nerve was repaired using CS/DSP and CS/GPTMS_DSP conduits to further investigate their ability to induce nerve regeneration in vivo. CS/GPTMS_DSP tubes resulted to be more fragile during suturing and, along a 12 week post-operative lapse of time, they detached from the distal nerve stump. On the contrary CS/DSP conduits promoted nerve fiber regeneration and functional recovery, leading to an outcome comparable to median nerve repaired by autograft.

Interleukin-36α axis is modulated in patients with primary Sjögren's syndrome

The aim of this study was to investigate the expression of the interleukin (IL)-36 axis in patients with primary Sjögren's syndrome (pSS). Blood and minor labial salivary glands (MSG) biopsies were obtained from 35 pSS and 20 non-Sjögren's syndrome patients (nSS) patients. Serum IL-36α was assayed by enzyme-linked immunosorbent assay (ELISA). IL-36α, IL-36R, IL-36RA, IL-38, IL-22, IL-17, IL-23p19 and expression in MSGs was assessed by reverse transcription-polymerase chain reaction (RT-PCR), and tissue IL-36α and IL-38 expression was also investigated by immunohistochemistry (IHC). αβ and γδ T cells and CD68(+) cells isolated from MSGs were also studied by flow cytometry and confocal microscopy analysis. IL-36α was over-expressed significantly in the serum and in the salivary glands of pSS. Salivary gland IL-36α expression was correlated with the expression levels of IL-17, IL-22 and IL-23p19. IL-38, that acts as inhibitor of IL-36α, was also up-regulated in pSS. αβ(+) CD3(+) T cells and CD68(+) cells were the major source of IL-36α in minor salivary glands of pSS. γδ T cells were not significantly expanded in the salivary glands of pSS but produced more IL-17, as their percentage correlated with the focus score. Higher expression of IL-36α and IL-36R was also demonstrated in γδ T cells isolated from pSS compared to controls. In this study we demonstrate that a significant increase in circulating and tissue levels of IL-36α occurs in pSS patients.

Interleukin (IL)-22 receptor 1 is over-expressed in primary Sjogren's syndrome and Sjögren-associated non-Hodgkin lymphomas and is regulated by IL-18

The aim of this study was to elucidate more clearly the role of interleukin (IL)-18 in modulating the IL-22 pathway in primary Sjögren's syndrome (pSS) patients and in pSS-associated lymphomas. Minor salivary glands (MSGs) from patients with pSS and non-specific chronic sialoadenitis (nSCS), parotid glands biopsies from non-Hodgkin lymphomas (NHL) developed in pSS patients, were evaluated for IL-18, IL-22, IL-22 receptor 1 (IL-22R1), IL-22 binding protein (IL-22BP) and signal transducer and activator of transcription-3 (STAT-3) expression. MSGs IL-22R1-expressing cells were characterized by confocal microscopy and flow cytometry in pSS, nSCS and healthy controls . The effect of recombinant IL-18 and IL-22 on peripheral blood mononuclear cells (PBMCs) from pSS and nSCS was studied by flow cytometry and reverse transcription-polymerase chain reaction (RT-PCR). MSGs of pSS and NHL were characterized by an imbalance between IL-22 and IL-22BP protein expression, with IL-18 and IL-22BP being expressed in a mutually exclusive manner and IL-18 and IL-22R1 being correlated directly. Aberrant expression of IL-22R1, induced by IL-18, was observed only among tissue and circulating myeloid cells of pSS patients and macrophages of NHL tissues of pSS patients, but not nSCS. IL-22R1 expression on PBMC of pSS was functional, as its stimulation with recombinant IL-22 significantly up-regulated the expression of STAT-3, IL-17 and IL-22. An IL-18-dependent aberrant expression of IL-22R1 on cells of haematopoietic origin seems to be a specific immunological signature of patients with pSS and pSS-associated lymphomas.

Serum level of testosterone, dihydrotestosterone and IGF-1 during an acute exacerbation of COPD and their relationships with inflammatory and prognostic indices: a pilot study

AIM

Acute exacerbations (AECOPD) of negatively influence the natural history of chronic obstructive pulmonary (COPD) and they are related to muscle dysfunction. In this pathway hypogonadism could play a pivotal role. Our study wants to evaluate possible relationships among prognostic indexes of AECOPD, represented by Acute Physiology and Chronic Health Evaluation (APACHE) II, inflammation (serum amyloid A, SSA) and anabolic hormones, especially less studied steroids, like dihydrotestosterone (DHT) e free-testosterone (f-T).

METHODS

Twenty-four patients (17 males; age 75 ± 13 yrs) were studied. On admission and at discharge a blood sample for total testosterone (T), DHT, insulin like grow factor 1 (IGF-1) and Serum Amyloid A (SSA) was obtained. f-T was calculated using Vermeulen's formula.

RESULTS

Descriptive statistical analysis shows reduced of T values (1.85 ± 2.28 ng/mL), f-T (0.028 ± 0.030 ng/mL), DHT (0.18 ± 0.19 ng/mL) and IGF-1 (91.840 ± 74.19 pg/mL). Calculating tertile for Apache II and SSA and using them as cut off point, three categories were made and used in the analysis (SSA< 10 mg/mL; 10-160 mg/mL; > 160 mg/mL); (APACHE II ≤ 10; 11-12; > 12). Using this classification, an inverse correlation between SAA and T (P = 0.01), f-T (0.01), DHT (0.001) and IGF-1 (P = 0.05) was found. Data show the same inverse relationship between APACHE II tertiles on one hand and T (P = 0.01) and f-T (P = 0.02) on the other hand.

CONCLUSION

Our data confirm systemic effects of AECOPD and the role of endocrinological derangements, suggesting a possible mechanism explaining them.

Comparison of plasma antioxidant levels in middle-aged and old male with idiopatic osteoporosis: preliminary data

OBJECTIVES

With the purpose of evaluating the role of oxidative stress (OS) in male idiopatic osteoporosis, we have evaluated plasma total antioxidant capacity (TAC) in patients classified according to age (< 65 or ≥ 65 yrs), with normal hormone values and in age-matched healthy control subjects.

PATIENTS AND METHODS

TAC was evaluated with a colorimetric method, using the system metamyoglobin-H2O2 and the chromogen ABTS; the latency time (LAG, sec) in the appearance of ABTS radical species is proportional to antioxidant content of the system.

RESULTS

We found slightly increased LAG values in middle-aged patients, compared with age-matched controls, probably expression of a compensatory mechanism to OS; on the contrary aged patients showed significantly lower LAG values in comparison with age-matched controls, suggesting a defective compensatory mechanism and, therefore, a risk for oxidative damage.

CONCLUSIONS

OS could be a possible mechanism underlying male osteoporosis, both in middle-aged and aged patients, but compensatory mechanisms seem to be defective in the last group.

Effect of vascular endothelial growth factor gene therapy on post-traumatic peripheral nerve regeneration and denervation-related muscle atrophy

Functional recovery after peripheral nerve injury depends on both improvement of nerve regeneration and prevention of denervation-related skeletal muscle atrophy. To reach these goals, in this study we overexpressed vascular endothelial growth factor (VEGF) by means of local gene transfer with adeno-associated virus (AAV). Local gene transfer in the regenerating peripheral nerve was obtained by reconstructing a 1-cm-long rat median nerve defect using a vein segment filled with skeletal muscle fibers that have been previously injected with either AAV2-VEGF or AAV2-LacZ, and the morphofunctional outcome of nerve regeneration was assessed 3 months after surgery. Surprisingly, results showed that overexpression of VEGF in the muscle-vein-combined guide led to a worse nerve regeneration in comparison with AAV-LacZ controls. Local gene transfer in the denervated muscle was obtained by direct injection of either AAV2-VEGF or AAV2-LacZ in the flexor digitorum sublimis muscle after median nerve transection and results showed a significantly lower progression of muscle atrophy in AAV2-VEGF-treated muscles in comparison with muscles treated with AAV2-LacZ. Altogether, our results suggest that local delivery of VEGF by AAV2-VEGF-injected transplanted muscle fibers do not represent a rational approach to promote axonal regeneration along a venous nerve guide. By contrast, AAV2-VEGF direct local injection in denervated skeletal muscle significantly attenuates denervation-related atrophy, thus representing a promising strategy for improving the outcome of post-traumatic neuromuscular recovery after nerve injury and repair.

Estrogens as antioxidant modulators in human fertility

Among treatments proposed for idiopathic male infertility, antiestrogens, like tamoxifen, play a possible role. On the other hand, oxidative stress is a mechanism well recognized for deleterious effects on spermatozoa function. After reviewing the literature on the effects of estrogens in modulation of antioxidant systems, in both sexes, and in different in vivo and in vitro models, we suggest, also on the basis of personal data, that a tamoxifen treatment could be active via an increase in seminal antioxidants.

Relationship between plasma antioxidants and thyroid hormones in chronic obstructive pulmonary disease

BACKGROUND

A low-T₃ syndrome is observed in chronic diseases, but its treatment is still debated. Chronic obstructive pulmonary disease (COPD) has not been conclusively studied under this aspect. COPD is a complex condition, which cannot be considered a lung-related disorder, but rather a systemic disease also associated to increased oxidative stress. We evaluated thyroid hormones and antioxidant systems, the lipophilic Coenzyme Q10 (CoQ₁₀) and total antioxidant capacity (TAC) in COPD patients to reveal the presence of a low-T₃ syndrome in COPD and investigate the correlation between thyroid hormones, lung function parameters and antioxidants.

METHODS

We studied: 32 COPD patients and 45 controls, evaluating thyrotropin (TSH), free-triiodotyronine (fT₃), free-tetraiodotyronine (fT₄), CoQ₁₀ (also corrected for cholesterol) and TAC. CoQ₁₀ was assayed by HPLC; TAC by the metmyoglobin-ABTS method and expressed as latency time (LAG) in radical species appearance.

RESULTS

We found significantly lower LAG values, fT₃ and fT₄ levels and significantly higher TSH in COPD patients vs. controls. LAG values significantly correlated with fT₃ concentration. 12 out of 32 patients exhibited fT₃ levels lower than normal range. So we divided COPD patients in 2 groups on the basis of the fT₃ concentration (normal fT₃ COPD and low fT₃ COPD). We observed lower LAG values in normal fT₃-COPD, compared to healthy subjects, with a further significant reduction in low fT₃-COPD patients. Moreover higher TSH concentration was present in normal fT₃-COPD, compared to healthy subjects, with a further significant increase in low fT₃-COPD patients. CoQ₁₀/cholesterol ratio was higher in low fT₃-COPD vs. normal fT₃-COPD, with a nearly significant difference.

CONCLUSIONS

These data seem to indicate an increased oxidative stress in low fT₃-COPD and a role of fT₃ in modulating antioxidant systems. However low fT₃ levels are joined to metabolic indexes of true hypothyroidism, suggesting that elevated CoQ₁₀ expresses a reduced tissue utilization. These data might suggest the need of thyroid replacement therapy in such a condition.

Phosphate glass fibres and their role in neuronal polarization and axonal growth direction

Phosphate glass fibres with composition 50P(2)O(5)-30CaO-9Na(2)O-3SiO(2)-3MgO-(5-x)K(2)O-xTiO(2)mol.% (x=0, 2.5, 5, respectively coded as TiPS(0), TiPS(2.5) and TiPS(5)) were drawn following the preform drawing approach. A 20-day solubility test in bi-distilled water was carried out on glass fibres with different compositions and diameters ranging between 25 and 82 μm. The results show that the glass composition, the initial fibre diameter and the thermal treatment are the main factors influencing the dissolution kinetics and that the fibres maintain their structural integrity and composition during dissolution. Biological tests were carried out on aligned TiPS(2.5) glass fibres using Neonatal Olfactory Bulb Ensheathing Cell Line (NOBEC) and Dorsal Root Ganglia (DRG) neurons. The fibres showed to be permissive substrates for cell adhesion and proliferation. The aligned configuration of the fibres seemed to provide a directional cue for growing axons of DRG neurons, which showed to sprout and grow long neurites along the fibre axis direction. These promising findings encourages further studies to evaluate the potential use of resorbable glass fibres (e.g.in combination with a nerve guidance tube) for the enhancement of the peripheral nerve healing with the role of supporting and guiding the cells involved in the nerve regeneration.

Mesenchymal stem cell interaction with a non-woven hyaluronan-based scaffold suitable for tissue repair

The fabrication of biodegradable 3-D scaffolds enriched with multipotent stem cells seems to be a promising strategy for the repair of irreversibly injured tissues. The fine mechanisms of the interaction of rat mesenchymal stem cells (rMSCs) with a hyaluronan-based scaffold, i.e. HYAFF(R)11, were investigated to evaluate the potential clinical application of this kind of engineered construct. rMSCs were seeded (2 x 10(6) cells cm(-2)) on the scaffold, cultured up to 21 days and analysed using appropriate techniques. Light (LM), scanning (SEM) and transmission (TEM) electron microscopy of untreated scaffold samples showed that scaffolds have a highly porous structure and are composed of 15-microm-thick microfibres having a rough surface. As detected by trypan blue stain, cell adhesion was high at day 1. rMSCs were viable up to 14 days as shown by CFDA assay and proliferated steadily on the scaffold as revealed by MTT assay. LM showed rMSCs in the innermost portions of the scaffold at day 3. SEM revealed a subconfluent cell monolayer covering 40 +/- 10% of the scaffold surface at day 21. TEM of early culture showed rMSCs wrapping individual fibres with regularly spaced focal contacts, whereas confocal microscopy showed polarized expression of CD44 hyaluronan receptor; TEM of 14-day cultures evidenced fibronexus formation. Immunohistochemistry of 21-day cultures showed that fibronectin was the main matrix protein secreted in the extracellular space; decorin and versican were seen in the cell cytoplasm only and type IV collagen was minimally expressed. The expression of CD90, a marker of mesenchymal stemness, was found unaffected at the end of cell culture. Our results show that HYAFF(R)11 scaffolds support the adhesion, migration and proliferation of rMSCs, as well as the synthesis and delivery of extracellular matrix components under static culture conditions without any chemical induction. The high retention rate and viability of the seeded cells as well as their fine modality of interaction with the substrate suggest that such scaffolds could be potentially useful when wide tissue defects are to be repaired as in the case of cartilage repair, wound healing and large vessel replacement.

Functional and morphological assessment of a standardized crush injury of the rat median nerve

The availability of effective experimental models for investigating nerve regeneration and designing new strategies for promoting this unique repair process is important. The aim of this study was to standardize a rat median nerve crush injury model using a non-serrated clamp exerting a compression force of 17.02 MPa for a duration of 30s. Results showed that functional recovery, evaluated by grasping test, was already detectable at day-12 and progressively increased until day-28 after which animal performance plateaued until the end of testing (day-42), reaching a range of 75-80% of pre-operative values. Morphological analysis on the median nerve segments, distal to the crush lesion, which were withdrawn at the end of the experiment showed that regenerated nerve fibers are significantly more numerous and densely packed; they are also smaller and have a thinner myelin sheath compared to controls. Together, these results provide a baseline characterization of the crush median nerve injury experimental model for its employment in the investigation of nerve regeneration research, especially when a reproducible regeneration process is required, such as for the study of biological mechanisms of peripheral nerve fiber regeneration or development of new therapeutic agents for promoting posttraumatic nerve repair.

Use of hybrid chitosan membranes and N1E-115 cells for promoting nerve regeneration in an axonotmesis rat model

Many studies have been dedicated to the development of scaffolds for improving post-traumatic nerve regeneration. The goal of this study was to develop and test hybrid chitosan membranes to use in peripheral nerve reconstruction, either alone or enriched with N1E-115 neural cells. Hybrid chitosan membranes were tested in vitro, to assess their ability in supporting N1E-115 cell survival and differentiation, and in vivo to assess biocompatibility as well as to evaluate their effects on nerve fiber regeneration and functional recovery after a standardized rat sciatic nerve crush injury. Functional recovery was evaluated using the sciatic functional index (SFI), the static sciatic index (SSI), the extensor postural thrust (EPT), the withdrawal reflex latency (WRL) and ankle kinematics. Nerve fiber regeneration was assessed by quantitative stereological analysis and electron microscopy. All chitosan membranes showed good biocompatibility and proved to be a suitable substrate for plating the N1E-115 cellular system. By contrast, in vivo nerve regeneration assessment after crush injury showed that the freeze-dried chitosan type III, without N1E-115 cell addition, was the only type of membrane that significantly improved posttraumatic axonal regrowth and functional recovery. It can be thus suggested that local enwrapping with this type of chitosan membrane may represent an effective approach for the improvement of the clinical outcome in patients receiving peripheral nerve surgery.

The paradigm of postconditioning to protect the heart

Ischaemic preconditioning limits the damage induced by subsequent ischaemia/reperfusion (I/R). However, preconditioning is of little practical use as the onset of an infarction is usually unpredictable. Recently, it has been shown that the heart can be protected against the extension of I/R injury if brief (10–30 sec.) coronary occlusions are performed just at the beginning of the reperfusion. This procedure has been called postconditioning (PostC). It can also be elicited at a distant organ, termed remote PostC, by intermittent pacing (dyssynchrony-induced PostC) and by pharmacological interventions, that is pharmacological PostC. In particular, brief applications of intermittent bradykinin or diazoxide at the beginning of reperfusion reproduce PostC protection. PostC reduces the reperfusion-induced injury, blunts oxidant-mediated damages and attenuates the local inflammatory response to reperfusion. PostC induces a reduction of infarct size, apoptosis, endothelial dysfunction and activation, neutrophil adherence and arrhythmias. Whether it reduces stunning is not clear yet. Similar to preconditioning, PostC triggers signalling pathways and activates effectors implicated in other cardioprotective manoeuvres. Adenosine and bradykinin are involved in PostC triggering. PostC triggers survival kinases (RISK), including A t and extracellular signal-regulated kinase (ERK). Nitric oxide, via nitric oxide synthase and non-enzymatic production, cyclic guanosine monophosphate (cGMP) and protein kinases G (PKG) participate in PostC. PostC-induced protection also involves an early redox-sensitive mechanism, and mitochondrial adenosine-5′ -triphosphate (ATP)-sensitive K⁺ and PKC activation. Protective pathways activated by PostC appear to converge on mitochondrial permeability transition pores, which are inhibited by acidosis and glycogen synthase kinase-3β (GSK-3β). In conclusion, the first minutes of reperfusion represent a window of opportunity for triggering the aforementioned mediators which will in concert lead to protection against reperfusion injury. Pharmacological PostC and possibly remote PostC may have a promising future in clinical scenario.

Estimation of chemical toxicity to wildlife species using interspecies correlation models

Ecological risks to wildlife are typically assessed using toxicity data for relatively few species and with limited understanding of differences in species sensitivity to contaminants. Empirical interspecies correlation models were derived from LD50 values for 49 wildlife species and 951 chemicals. The standard wildlife test species Japanese quail (Coturnix japonica) and mallard (Anas platyrhynchos) were determined to be good surrogates for many species within the database. Cross-validation of all models predicted toxicity values within 5-fold and 10-fold of the actual values with 85 and 95% certainty, respectively. Model robustness was not consistently improved by developing correlation models within modes of action (MOA); however, improved models for neurotoxicants, carbamates, and direct acting organophosphorous acetylcholenesterase inhibiting compounds indicate that toxicity estimates may improve if MOA-specific models are built with robust datasets. There was a strong relationship between taxonomic distance and cross-validation prediction success (chi2 = 297, df = 12, p < 0.0001), with uncertainty increasing with larger taxonomic distance between the surrogate and predicted species. Interspecies toxicity correlations provide a tool for estimating contaminant sensitivity with known levels of uncertainty for a diversity of wildlife species.

Long-term functional and morphological assessment of a standardized rat sciatic nerve crush injury with a non-serrated clamp

We have recently described the sequence of functional and morphologic changes occurring after a standardized sciatic nerve crush injury. An 8-week post-injury time was used because this end point is the far most used. Unexpectedly, both functional and morphological data revealed that animals had still not recovered to normal pre-injury levels. Therefore, the present study was designed in order to prolong the observation up to 12 weeks. Functional recovery was evaluated using sciatic functional index (SFI), static sciatic index (SSI), extensor postural thrust (EPT), withdrawal reflex latency (WRL) and ankle kinematics. In addition, quantitative morphology was carried out on regenerated nerve fibers. A full functional recovery was predicted by SFI/SSI, EPT and WRL but not all ankle kinematics parameters. Moreover, only two morphological parameters (myelin thickness/axon diameter ratio and fiber/axon diameter ratio) returned to normal values. Data presented in this paper provide a baseline for selecting the adequate end-point and methods of recovery assessment for a rat sciatic nerve crush study and suggest that the combined use of functional and morphological analysis should be recommended in this experimental model.

Lack of topographic specificity in nerve fiber regeneration of rat forelimb mixed nerves

Multiple nerve repair by means of a Y-shaped nerve guide represents a good model for studying the specificity of peripheral nerve fiber regeneration. Here we have used it for investigating the specificity of axonal regeneration in mixed nerves of the rat forelimb model. The left median and ulnar nerves, in adult female rats, were transected and repaired with a 14-mm Y-shaped conduit. The proximal end of the Y-shaped conduit was sutured to the proximal stump of either the median nerve or the ulnar nerve. Ten months after surgery, rats were tested for functional recovery of each median and ulnar nerve. Quantitative morphology of regenerated myelinated nerve fibers was then carried out by the two-dimensional disector technique. Results showed that partial recovery of both median and ulnar nerve motor function was regained in all experimental groups. Performance in the grasping test was significantly lower when the ulnar nerve was used as the proximal stump. Ulnar test assessment showed no significant difference between the two Y-shaped repair groups. The number of regenerated nerve fibers was significantly higher in the median nerve irrespectively of the donor nerve, maintaining the same proportion of myelinated fibers between the two nerves (about 60% median and 40% ulnar). On the other hand, nerve fiber size and myelin thickness were significantly larger in both distal nerves when the median nerve was used as the proximal donor nerve stump. G-ratio and myelin thickness/axon diameter ratio returned to normal values in all experimental groups. These results demonstrate that combined Y-shaped-tubulization repair of median and ulnar nerves permits the functional recovery of both nerves, independently from the proximal donor nerve employed, and that tissue, and not topographic, specificity guides nerve fiber regeneration in major forelimb mixed nerves of rats.

Comparison of fresh and predegenerated muscle-vein-combined guides for the repair of rat median nerve

Over the last 10 years, we have investigated a particular type of bioengineered nerve guide, the muscle-vein-combined tube, which is made by filling a vein with skeletal muscle. In our previous studies we have always used fresh skeletal muscle to fill vein conduits. In the present study we compared the use of fresh and predegenerated (freeze-thawed) skeletal muscle for muscle-vein-combined nerve guides. In this study, a 10-mm-long rat median nerve defect was repaired using either type of nerve guide. The samples were analyzed 5 and 30 days after surgery by light and electron microscopy. In addition, reverse transcription polymerase chain reaction (RT-PCR) was carried out to investigate the expression of mRNAs coding for glial markers, as well as glial growth factor (NRG1) and its receptors (erbB2 and erbB3). Results showed differences between the two types of nerve guides at postoperative day 5; however, no difference was detected at day 30 suggesting that both types of tissue-engineered conduit are effective for repairing peripheral nerve defects in this experimental model.

Nerve regeneration along bioengineered scaffolds

Tissue engineering has recently seen great advancements in many medical fields, including peripheral nerve reconstruction. In the rat median nerve model, we investigated nerve repair by means of bioengineered tissue scaffolds (muscle-vein-combined tubes) focusing on changes in the neuregulin-1/ErbB-receptor system which represents one of the main regulatory systems of axo-glial interaction in peripheral nerves. Repaired nerves were withdrawn at 5, 15, and 30 days postoperative and processed for morphological and retro-transcriptase polymerase chain reaction (RT-PCR) analysis. Results revealed an early and progressive increase in the expression of NRG1alpha isoform only, while the appearance of the beta isoform of NRG1, which is normally present in peripheral nerves, was delayed. In regards to ErbB2 and ErbB3 receptors, their expression increased progressively inside the muscle-vein-combined scaffolds, though with different kinetics. Taken together, these results suggest that variations in neuregulin-1/ErbB system activation play a key role in peripheral nerve regeneration along bioengineered muscle-vein-combined scaffolds. Since similar variations are also detectable in denervated skeletal muscles, it can be hypothesized that the existence of a NRG1's autocrine/paracrine trophic loop shared by both glial and muscle fibers could be responsible for the effectiveness of muscle-vein-combined conduits for repairing nerve defects.

Schwann-cell proliferation in muscle-vein combined conduits for bridging rat sciatic nerve defects

Among the various grafting procedures that have been studied as alternatives to traditional fresh nerve autografts for the repair of severed peripheral nerves, muscle-vein-combined graft conduits have recently been devised and successfully employed. In the present study, the early presence, origin, and proliferation activity of Schwann cells (SCs) along this particular type of biological graft conduit have been investigated, using antibodies directed against glial fibrillar acid protein (GFAP), a protein that is specifically expressed in glial cells, and proliferating cell nuclear antigen (PCNA), a protein that is expressed by cells during DNA synthesis. Results showed that the muscle-vein-combined graft was progressively invaded by a number of GFAP-immunopositive SCs, many of which were also found to be immunopositive for PCNA, thus demonstrating that their proliferation continues to occur inside the graft. Among the molecules that could be involved in the stimulation of Schwann-cell proliferation is neuregulin-1 (NRG-1) that mediates its effects by binding to the ErbB receptor tyrosine kinase family. In the present study, the authors report on the RT-PCR analysis for NRG-1 and ErbB3 mRNAs, showing an overall increase in the content of these transcripts inside the muscle-vein-combined graft. These results suggest that the muscle-vein-combined graft conduit constitutes an environment favorable to potentiate Schwann-cell proliferation during the early regeneration phases.

A seroepidemiological study of toxoplasma gondii infection in children of northern Greece

The aims of this study were to determine the incidence of toxoplasmosis in children ofthe northern Greece region through the evaluation of serologic examination. Sera of 486 children, aged between 6 months and 15 years, suffering from different clinical entities, were tested for anti-Toxoplasma gondii specific IgG antibodies, using an ELISA (enzyme linked immunosorbent assay) technique. In this survey, a high percentage (11.1 percent) of the hospitalized children reacted positively to this method. Males and females had equal prevalence, 11 percent and 11.2 percent, respectively. Seropositivity rate was higher in children aged between 6 and 10 years old. In conclusion, our results indicate toxoplasma infection is an important public health problem affecting children and adolescents in northern Greece. We believe that the study described here could be considered for inclusion in existing national screening programs for hospitalized children.