Diagnosis of hepatic steatosis and steatohepatitis in people with new-onset type 2 diabetes: a multidisciplinary approach

AIMS

Non-Alcoholic-Fatty-Liver-Disease (NAFLD) is the most common cause of chronic liver disease in Western countries; closely linked to obesity and type 2 diabetes (T2DM), it is an additional cardiovascular risk factor. The aim of this study is to investigate the prevalence of NAFLD at T2DM onset.

METHODS

122 newly diagnosed T2DM patients were enroled; NAFLD was diagnosed using ultrasound and fibrosis risk calculated with an FIB4-score. Intermediate and high-risk patients were referred to a hepatologist and underwent transient elastography (TE).

RESULTS

At T2DM diagnosis, 25% of patients were overweight, 47% were obese; ultrasound steatosis was present in 79% of patients; the average FIB-4 score was 1.4 (0.7). The NAFLD population was characterised by higher presence of obesity (60%, p 0.06); hypertension (56%, p 0.00); AST (26.3 (23.6) UI/L; p 0.00); ALT (49.3(41.0) UI/L p 0.00); FIB-4 score (1.6 (0.8); p 0.00). Among patients referred to a hepatologist, at TE, 65% had severe steatosis, 22% significant fibrosis and 25% advanced fibrosis.

CONCLUSION

This is the first proposal of a NAFLD screening model at T2DM diagnosis. The high prevalence of fibrosis found at the early stage T2DM confirms the compelling need for early management of NAFLD through cost-effective screening and long-term monitoring algorithms.

A stem cell zoo uncovers intracellular scaling of developmental tempo across mammals

Differential speeds in biochemical reactions have been proposed to be responsible for the differences in developmental tempo between mice and humans. However, the underlying mechanism controlling the species-specific kinetics remains to be determined. Using in vitro differentiation of pluripotent stem cells, we recapitulated the segmentation clocks of diverse mammalian species varying in body weight and taxa: marmoset, rabbit, cattle, and rhinoceros. Together with mouse and human, the segmentation clock periods of the six species did not scale with the animal body weight, but with the embryogenesis length. The biochemical kinetics of the core clock gene HES7 displayed clear scaling with the species-specific segmentation clock period. However, the cellular metabolic rates did not show an evident correlation. Instead, genes involving biochemical reactions showed an expression pattern that scales with the segmentation clock period. Altogether, our stem cell zoo uncovered general scaling laws governing species-specific developmental tempo.

Papillomavirus Infection as Potential Cause of Miscarriage in the Early Gestational Age: A Prospective Study

The possible association between human papillomavirus (HPV) infection and negative pregnancy outcomes has been debated in the literature, with conflicting results from clinical trials. While some authors support a link between HPV and miscarriage, others argue that the mere detection of the virus does not necessarily indicate a causal relationship with negative pregnancy outcomes. In this study, we conducted a prospective, controlled investigation of the potential association between HPV infection and miscarriage. Our study included 59 women who had experienced a miscarriage and 57 women who had undergone voluntary termination of pregnancy (TOP) within the 12th week of gestation. We assessed HPV prevalence, maternal age, and HPV genotype in both groups and evaluated the relationship between these factors and pregnancy outcome. Unlike previous studies that only identified HPV in cases of abortion, we also correlated the positivity of chorionic villi with gestational age in both groups. We found a close correlation between positive chorionic villi and very early gestational age, with all 13 cases of virus-positive chorionic villi in the miscarriage group occurring in gestational periods of less than 8 + 5 weeks (<60 days) (RR = 28.6). Our analysis showed no correlation between HPV infection and maternal age or viral genotypes. The results suggest that the presence of HPV alone is not enough to cause spontaneous abortion, but a high viral load in early pregnancy may increase the risk of negative outcomes. These findings have important implications for the management of HPV infection during pregnancy and may provide a rationale for the use of HPV vaccines to reduce the incidence of spontaneous abortion and infertility due to preclinical spontaneous abortions.

Biolink Model: A universal schema for knowledge graphs in clinical, biomedical, and translational science

Within clinical, biomedical, and translational science, an increasing number of projects are adopting graphs for knowledge representation. Graph‐based data models elucidate the interconnectedness among core biomedical concepts, enable data structures to be easily updated, and support intuitive queries, visualizations, and inference algorithms. However, knowledge discovery across these “knowledge graphs” (KGs) has remained difficult. Data set heterogeneity and complexity; the proliferation of ad hoc data formats; poor compliance with guidelines on findability, accessibility, interoperability, and reusability; and, in particular, the lack of a universally accepted, open‐access model for standardization across biomedical KGs has left the task of reconciling data sources to downstream consumers. Biolink Model is an open‐source data model that can be used to formalize the relationships between data structures in translational science. It incorporates object‐oriented classification and graph‐oriented features. The core of the model is a set of hierarchical, interconnected classes (or categories) and relationships between them (or predicates) representing biomedical entities such as gene, disease, chemical, anatomic structure, and phenotype. The model provides class and edge attributes and associations that guide how entities should relate to one another. Here, we highlight the need for a standardized data model for KGs, describe Biolink Model, and compare it with other models. We demonstrate the utility of Biolink Model in various initiatives, including the Biomedical Data Translator Consortium and the Monarch Initiative, and show how it has supported easier integration and interoperability of biomedical KGs, bringing together knowledge from multiple sources and helping to realize the goals of translational science.

An Open-Access Platform for Translating Diabetes and Cardiometabolic Disease Genetics Into Accessible Knowledge

Most associations from genome-wide association studies (GWAS) result from as-yet-unknown alterations of molecular or cellular function; the causal variants and effector genes responsible for them, and the tissues and pathways through which they act, remain largely unknown. Thousands of associated loci have now been identified for each common disease and its related traits. In order to translate GWAS data into biological knowledge, they must be integrated with functional genomic annotations reflecting tissue-specific regulation and with the results of bioinformatic methods that predict the functional effects of associations. However, these data types are typically spread across disparate resources, and working with them requires bioinformatic expertise.

To make these results accessible and understandable to the broader diabetes and cardiometabolic disease research communities, we have developed the open-access Common Metabolic Diseases Knowledge Portal (CMDKP; cmdkp.org), which brings together a robust software and data storage platform with a streamlined and intuitive user interface for four disease areas: diabetes (both types 1 and 2); cardiovascular disease; cerebrovascular disease; and sleep and circadian disorders.

The CMDKP enables researchers to access and explore a comprehensive matrix of genetic, genomic, and computational results. It includes 3 classes of genomic data: 1) GWAS summary statistics from the most current and authoritative datasets available, as identified by disease-area experts; 2) functional genomic annotations, such as chromatin accessibility, that reflect the tissue-specific regulatory potential of genomic regions; and 3) the results of bioinformatic methods applied to these aggregated data (for example, overlap-aware meta-analysis to determine “bottom-line” p-values, the GREGOR method for determining tissue-specific enrichment of genetic associations, the MAGMA method for generating gene-level association scores, and more). All of these data types are integrated and accessible via interactive tools that allow researchers to explore and evaluate the data in order to identify candidate disease effector genes for further research. The CMDKP provides researchers with the data and tools necessary to translate genetic associations and functional annotations into knowledge about disease mechanisms and potential therapeutic targets.

Conservative management of CIN2 p16 positive lesions in women with multiple HPV infection

BACKGROUND

According to the 2006 American Society for Colposcopy and Cervical Pathology guidelines, positive CIN2 p16 in women over the age of 25 should be managed with excisional treatment. However, excisional treatment is associated with physical, psychological and obstetric morbidity and can have a negative impact on sexual function. In our study we sought to identify a clear management strategy, addressing the impact of routine use of p16 immunohistochemistry in this population and identify appropriate criteria for patient selection with the aim of reducing over-treatment.

METHOD

We studied the medical records of 130 patients who had undergone laser therapy for CIN2. Each patient underwent colposcopy, biopsy and HPV test and were tested for p16 protein,. Patients were divided based on HPV infection into: single infections, multiple infections. All patients underwent ZTA laser therapy with follow-up (2-year follow-up).

STATISTICAL ANALYSIS

Contingency tables were created to evaluate the correlation between single, multiple and CIN2+ infections. Values with p < 0.05 were considered statistically significant.

RESULTS

Single infections had a histological regression of 61.8% (21/34) and a histological persistence rate of 35.3% (12/34), which was greater than the multiple infection rate. The common characteristic that the women with persistence and progression had was the dimension of the lesion and the genotype 16. Ten cases of histological persistence and the only case of progression had one lesion greater than three quarters of the cervix.

CONCLUSIONS

With the progress of our understanding of the natural history of infection from human papillomavirus and the increasing use of colposcopy, thanks to the addition of HPV genotyping and the technique of immunohistochemistry, conservative management of these lesions is now possible.

0702 Phrenic Nerve Stimulation Improves Oxygenation And Quality Of Life In Patients With Central Sleep Apnea And History Of Cerebrovascular Accidents

Introduction

Central sleep apnea (CSA) is a recognized complication of cerebrovascular accidents (CVA), although CSA treatment in this setting is of uncertain benefit. A recent randomized clinical trial showed that transvenous phrenic nerve stimulation (TPNS, remedē system, Respicardia Inc.) treats CSA. The clinical impact of TPNS on CSA outcomes in the subgroup of patients with prior CVA was studied.

Methods

Six subjects with predominantly CSA and history of CVA &gt;6 months prior to enrollment in the remedē System Pivotal Trial were analyzed. Patients underwent attended full-night polysomnography prior to TPNS implantation and 6, 12 and 18 months on TPNS therapy. Apnea-hypopnea index (AHI) and sleep metrics were evaluated. The Epworth Sleepiness Scale (ESS) and Patient Global Assessment (PGA) questionnaire were completed at 12 months. Treated patients and former controls (therapy was turned on after 6 months) with 18 months of TPNS therapy were pooled for analysis based on months of therapy.

Results

Apnea-hypopnea index decreased from a median of 47 events/hour [interquartile range: 23, 71] at baseline to 15 [4,24], 17 [6,48], and 12 [8,27] at 6, 12, and 18 months. Comparable improvements were also seen in oxygen desaturation index (4%) and arousal index. Central apnea index decreased from 30 [21,61] to ≤3/hour at each follow up. Compared to baseline, ESS decreased by 5 [-10,-3] and 4 [-8,-4] points at 6 and 12 months, while moderate or markedly improved overall health per the PGA was reported by 4/6 and 3/6 patients, respectively. No patient reported recurrent CVA or transient ischemic attack.

Conclusion

Transvenous phrenic nerve stimulation improved sleep, daytime somnolence and quality of life in patients with CSA and prior CVA. Transvenous phrenic nerve stimulation is a novel therapy that may be an option for treating patients with CSA and prior CVA.

Support

Respicardia and NIH R01 HL 144859

Experimental Demonstration of Hadron Beam Cooling Using Radio-Frequency Accelerated Electron Bunches

Cooling of beams of gold ions using electron bunches accelerated with radio-frequency systems was recently experimentally demonstrated in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. Such an approach is new and opens the possibility of using this technique at higher energies than possible with electrostatic acceleration of electron beams. The challenges of this approach include generation of electron beams suitable for cooling, delivery of electron bunches of the required quality to the cooling sections without degradation of beam angular divergence and energy spread, achieving the required small angles between electron and ion trajectories in the cooling sections, precise velocity matching between the two beams, high-current operation of the electron accelerator, as well as several physics effects related to bunched-beam cooling. Here we report on the first demonstration of cooling hadron beams using this new approach.

Genomic damage induced by the widely used fungicide chlorothalonil in peripheral human lymphocytes

Chlorothalonil is an important broad spectrum fungicide widely used in agriculture, silviculture, and urban settings. As a result of its massive use, chlorothalonil was found in all environmental matrices, with consequent risks to the health of terrestrial and aquatic organisms, as well as for humans. We analyzed the effects of chlorothalonil on human lymphocytes using in vitro chromosomal aberrations (CAs) and micronuclei (MNi) assays. Lymphocytes were exposed to five concentrations of chlorothalonil: 0.600 µg/mL, 0.060 µg/mL, 0.030 µg/mL, 0.020 µg/mL, and 0.015 µg/mL, where 0.020 and 0.600 µg/mL represent the ADI and the ARfD concentration values, respectively, established by FAO/WHO for this compound; 0.030 and 0.060 μg/mL represent intermediate values of these concentrations and 0.015 μg/mL represents the ADI value established by the Canadian health and welfare agency. We observed cytogenetic effects of chlorothalonil on cultured human lymphocytes in terms of increased CAs and MNi frequencies at all tested concentrations, including the FAO/WHO ADI and ARfD values of 0.020 and 0.600 μg/mL, respectively, but with exception of the Canadian ADI value of 0.015 μg/mL. Finally, no sexes differences were found in the levels of CAs and MNi induced by different chlorothalonil concentrations. Similarly, the mitotic index and the cytokinesis-block proliferation index did not show any significant effect on the proliferative capacity of the cells, although at the chlorothalonil concentration of 0.600 μg/mL the P-values of both indices were borderline.

Krill oil, vitamin D and Lactobacillus reuteri cooperate to reduce gut inflammation

Current research into original therapies to treat intestinal inflammation is focusing on no-drug therapies. KLD is a mixture of krill oil (KO), probiotic Lactobacillus reuteri (LR), and vitamin D (VitD3). The aim of this study was to assess in vitro and in vivo the potential cooperative effects of KLD in reducing gut inflammation. Colorectal adenocarcinoma cell lines, CACO2 and HT29, and C57BL/6 mice were used for in vitro and in vivo analyses, respectively. Cells were exposed to cytomix (interferon gamma + tumour necrosis factor alpha (TNF-α)) to induce inflammation or co-exposed to cytomix and KO, LR and VitD3 alone or to cytomix and KLD. Animals were treated for 7 days with dextran sodium sulphate (DSS) to induce colitis or with DSS and KLD. In vitro assays: F-actin expression was analysed by immunofluorescence; scratch test and trans-epithelial electric resistance test were performed to measure wound healing; adhesion/invasion assays of adhesive and invasive Escherichia coli (AIEC) bacteria were made; mRNA expression of TNF-α, interleukin (IL)-8 and vitamin D receptor (VDR) was detected by quantitative PCR. In vivo assays: body weight, clinical score, histological score and large intestine weight and length were estimated; mRNA expression of TNF-α, IL-1β, IL-6, IL-10 by quantitative PCR; VDR expression was detected by quantitative PCR and immunohistochemistry. In vitro: KLD restores epithelial cell-cell adhesion and mucosal healing during inflammation, while decreases the adhesiveness and invasiveness of AIEC bacteria and TNF-α and IL-8 mRNA expression and increases VDR expression. In vivo: KLD significantly improves body weight, clinical score, histological score and large intestine length of mice with DSS-induced colitis and reduces TNF-α, IL-1β and IL-6 mRNA levels, while increases IL-10 mRNA and VDR levels. KLD has significant effects on the intestinal mucosa, strongly decreasing inflammation, increasing epithelial restitution and reducing pathogenicity of harmful commensal bacteria.

Re-emergent tremor in Parkinson's disease: the effect of dopaminergic treatment

BACKGROUND AND PURPOSE

Patients with Parkinson's disease (PD) with resting tremor may be affected by a tremor that appears after a varying latency while a posture is maintained, a phenomenon referred to as re-emergent tremor (RET). The aim of the study was to evaluate the occurrence and clinical features of RET in patients with PD tested off and on treatment, and to compare the effect of dopaminergic treatment on RET with the effect on resting and action tremor.

METHODS

We consecutively enrolled 100 patients with PD. Patients were clinically evaluated 24 h after withdrawal of therapy (off-treatment phase) and 60 min after therapy administration (on-treatment phase). We collected the demographic and clinical data of patients with PD. The severity of the disease was assessed by means of the Hoehn and Yahr scale and Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale part III. We evaluated the latency, severity and body side affected both off and on treatment in patients with RET.

RESULTS

Re-emergent tremor was present in 24% of the patients with PD off treatment and in 19% of the patients on treatment. Dopaminergic treatment reduced the clinical severity of RET. Dopaminergic treatment increased the number of patients with unilateral RET and reduced the number of those who had bilateral RET. RET and resting tremor responded similarly to dopaminergic treatment, whereas action tremor was less responsive. Patients with RET had milder motor symptoms than patients without RET both off and on treatment.

CONCLUSIONS

Dopaminergic treatment modified RET occurrence, severity and body distribution. Dopaminergic depletion plays a role in the pathophysiology of RET.

Fluorescence and electron microscopy to visualize the intracellular fate of nanoparticles for drug delivery

In order to design valid protocols for drug release via nanocarriers, it is essential to know the mechanisms of cell internalization, the interactions with organelles, and the intracellular permanence and degradation of nanoparticles (NPs) as well as the possible cell alteration or damage induced. In the present study, the intracellular fate of liposomes, polymeric NPs and mesoporous silica NPs (MSN) has been investigated in an in vitro cell system by fluorescence and transmission electron microscopy. The tested nanocarriers proved to be characterized by specific interactions with the cell: liposomes enter the cells probably by fusion with the plasma membrane and undergo rapid cytoplasmic degradation; polymeric NPs are internalized by endocytosis, occur in the cytoplasm both enclosed in endosomes and free in the cytosol, and then undergo massive degradation by lysosome action; MSN are internalized by both endocytosis and phagocytosis, and persist in the cytoplasm enclosed in vacuoles. No one of the tested nanocarriers was found to enter the nucleus. The exposure to the different nanocarriers did not increase cell death; only liposomes induced a reduction of cell population after long incubation times, probably due to cell overloading. No subcellular damage was observed to be induced by polymeric NPs and MSN, whereas transmission electron microscopy revealed cytoplasm alterations in liposome-treated cells. This important information on the structural and functional relationships between nanocarriers designed for drug delivery and cultured cells further proves the crucial role of microscopy techniques in nanotechnology.

Operational Head-on Beam-Beam Compensation with Electron Lenses in the Relativistic Heavy Ion Collider

Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. To date, the implemented compensation scheme approximately doubled the peak and average luminosities.

Embolization of left spermatic vein in non-obstructive azoospermic men with varicocele: role of FSH to predict the appearance of ejaculated spermatozoa after treatment

PURPOSE

Varicocele repair in non-obstructive azoospermia (NOA) was occasionally associated to ejaculated spermatozoa independently from clinical and laboratory measures. We performed a prospective study in infertile men affected by NOA and left side varicocele to find whether or not the appearance of ejaculated spermatozoa after varicocele repair is predicted by baseline measures.

METHODS

Patients with NOA and grade II, or grade III left side varicocele were submitted to hormone analysis and to scrotal color Doppler ultrasound (CDU). Azoospermia was confirmed in 23 patients aged 25-47 years who were than submitted to varicocele repair through a retrograde internal spermatic vein embolization. Patients were re-evaluated after 6 months.

RESULTS

Six months after varicocele repair 12 patients (52.2 %) were still azoospermic (Group 1) while 11 patients (47.8 %) reported ejaculated spermatozoa (Group 2) [sperm count: 1.3 × 10(6)/mL; 0.5 × 10(6)/mL-1.6 × 10(6)/mL (median 25th-75th centiles)]. Serum baseline FSH was lower in Group 2 compared to Group 1 (p = 0.012), while no differences between groups were revealed for all other clinical and laboratory parameters. ROC analysis indicated that baseline FSH level predicted the appearance of ejaculated spermatozoa after treatment [AUC = 0.811; 95 % Confidence Interval (CI) 0.6-0.9; p = 0.0029]. A cut-off level of FSH <10.06 mIU/mL identified 82.0 % of cases with ejaculated spermatozoa with a specificity of 81.8 % and a sensitivity of 83.3 %.

CONCLUSION

Selected patients with NOA may show ejaculated spermatozoa after a non-invasive repair of a left side varicocele, therefore avoiding testicular sperm extraction. Baseline serum FSH was a valuable predictor for ejaculated spermatozoa after treatment.

Low ozone concentrations stimulate cytoskeletal organization, mitochondrial activity and nuclear transcription

Ozone therapy is a modestly invasive procedure based on the regeneration capabilities of low ozone concentrations and used in medicine as an alternative/adjuvant treatment for different diseases. However, the cellular mechanisms accounting for the positive effects of mild ozonization are still largely unexplored. To this aim, in the present study the effects of low ozone concentrations (1 to 20 µg O₃/mL O₂) on structural and functional cell features have been investigated in vitro by using morphological, morphometrical, cytochemical and immunocytochemical techniques at bright field, fluorescence and transmission electron microscopy. Cells exposed to pure O₂ or air served as controls. The results demonstrated that the effects of ozone administration are dependent on gas concentration, and the cytoskeletal organization, mitochondrial activity and nuclear transcription may be differently affected. This suggests that, to ensure effective and permanent metabolic cell activation, ozone treatments should take into account the cytological and cytokinetic features of the different tissues.

Internalized chitosan nanoparticles persist for long time in cultured cells

Chitosan-based nanoparticles (chiNPs) are considered to be potentially good carriers for the sustained intracellular delivery of specific molecules. However, scarce attention has been paid to the long-lasting permanence of these NPs in the intracellular milieu, as well as to their intracellular fate (i.e., distribution, interaction with cell organelles, and degradation) in the long term. In the present study, the presence and subcellular location of FITC-labelled chiNPs were monitored in HeLa cells up to 14 days post-administration using multicolorfluorescence confocal microscopy and diaminobenzidine photo-oxidation at transmission electron microscopy. The main result of the present study is the demonstration that internalized chiNPs persist inside the cell up to two weeks, occurring in both the cytoplasm and nucleus; accordingly, chiNPs are able to pass from mother to daughter cells through several mitotic cycles. The cells did not show increased mortality or structural damage up to 14 days after chiNP exposure.

Correlates of low testosterone in men with chronic spinal cord injury

Although high rates of serum testosterone deficiency have been reported in men with spinal cord injury (SCI), its determinants and attributes are not yet established. The aim of this study was to recognize, among putative determinants and attributes of androgen deficiency, those significantly associated to low testosterone after adjustment for confounders recognizable in men with chronic SCI. A biochemical androgen deficiency (total testosterone <300 ng/dL) was exhibited by 18 of 51 patients (35.3%). Significant correlates of testosterone levels were as follows: weekly leisure time physical activity (LTPA) explored by the LTPA Questionnaire for people with SCI, body mass index (BMI), homeostatic model assessment of insulin resistance (HOMA-IR), triglycerides and sexual symptoms, explored by the aging males' symptom (AMS) questionnaire. At the multiple linear regression analysis, among putative determinants of low testosterone, only weekly LTPA and BMI exhibited a significant association with testosterone levels, explaining 54.2 and 9.0% of testosterone variability respectively. At the linear regression models, among various putative attributes of androgen deficiency, only lower sexual desire and, at a lesser extent, higher HOMA-IR, exhibited significant associations with lower testosterone levels, after adjustment for BMI, age, comorbidities and weekly LTPA. In conclusion, poor LTPA, high BMI and low sexual desire are independent predictors of low testosterone in men with chronic SCI. This is relevant to clinical practice, as all these features are routinely assessed in rehabilitation settings for SCI. As poor LTPA and high BMI are modifiable life-style related risk factors, prospective studies could clarify whether life-style modification could increase the level of testosterone and improve the low sexual desire, relevant clinical attribute of low testosterone in men with SCI.

Tracing nanoparticles and photosensitizing molecules at transmission electron microscopy by diaminobenzidine photo-oxidation

During the last three decades, diaminobenzidine photo-oxidation has been applied in a variety of studies to correlate light and electron microscopy. Actually, when a fluorophore is excited by light, it can induce the oxidation of diaminobenzidine into an electron-dense osmiophilic product, which precipitates in close proximity to the fluorophore, thereby allowing its ultrastructural detection. This method has very recently been developed for two innovative applications: tracking the fate of fluorescently labeled nanoparticles in single cells, and detecting the subcellular location of photo-active molecules suitable for photodynamic therapy. These studies established that the cytochemical procedures exploiting diaminobenzidine photo-oxidation represent a reliable tool for detecting, inside the cells, with high sensitivity fluorescing molecules. These procedures are trustworthy even if the fluorescing molecules are present in very low amounts, either inside membrane-bounded organelles, or at the surface of the plasma membrane, or free in the cytosol. In particular, diaminobenzidine photo-oxidation allowed elucidating the mechanisms responsible for nanoparticles internalization in neuronal cells and for their escape from lysosomal degradation. As for the photo-active molecules, their subcellular distribution at the ultrastructural level provided direct evidence for the lethal multiorganelle photo-damage occurring after cell photo-sensitization. In addition, DAB photo-oxidized samples are suitable for the ultrastructural detection of organelle-specific molecules by post-embedding gold immunolabeling.

Simultaneous ultrastructural analysis of fluorochrome-photoconverted diaminobenzidine and gold immunolabelling in cultured cells

Diaminobenzidine photoconversion is a technique by which a fluorescent dye is transformed into a stably insoluble, brown, electrondense signal, thus enabling examination at both bright field light microscopy and transmission electron microscopy. In this work, a procedure is proposed for combining photoconversion and immunoelectron microscopy: in vitro cell cultures have been first submitted to photoconversion to analyse the intracellular fate of either fluorescent nanoparticles or photosensitizing molecules, then processed for transmission electron microscopy; different fixative solutions and embedding media have been used, and the ultrathin sections were finally submitted to post-embedding immunogold cytochemistry. Under all conditions the photoconversion reaction product and the target antigen were properly detected in the same section; Epon-embedded, osmicated samples required a pre-treatment with sodium metaperiodate to unmask the antigenic sites. This simple and reliable procedure exploits a single sample to simultaneously localise the photoconversion product and a variety of antigens allowing a specific identification of subcellular organelles at the ultrastructural level.

Absence of an independent association between serum uric acid and left ventricular mass in Caucasian hypertensive women and men

BACKGROUND AND AIM

Experimentally uric acid may induce cardiomyocyte growth and interstitial fibrosis of the heart. However, clinical studies exploring the relationship between serum uric acid (SUA) and left ventricular (LV) mass yielded conflicting results. The aim of our study was to evaluate the relationships between SUA and LV mass in a large group of Caucasian essential hypertensive subjects.

METHODS AND RESULTS

We enrolled 534 hypertensive patients free of cardiovascular complications and without severe renal insufficiency. In all subjects routine blood chemistry, including SUA determination, echocardiographic examination and 24 h ambulatory blood pressure (BP) monitoring were obtained. In the overall population we observed no significant correlation of SUA with LV mass indexed for height(2.7) (LVMH(2.7)) (r = 0.074). When the same relationship was analysed separately in men and women, we found a statistically significant correlation in female gender (r = 0.27; p < 0.001), but not in males (r = -0.042; p = NS). When we grouped the study population in sex-specific tertiles of SUA, an increase in LVMH(2.7) was observed in the highest tertiles in women (44.5 ± 15.6 vs 47.5 ± 16 vs 55.9 ± 22.2 g/m(2.7); p < 0.001), but not in men. The association between SUA and LVMH(2.7) in women lost statistical significance in multiple regression analyses, after adjustment for age, 24 h systolic BP, body mass index, serum creatinine and other potential confounders.

CONCLUSIONS

Our findings do not support an independent association between SUA and LV mass in Caucasian men and women with arterial hypertension.

Muscleblind-like1 undergoes ectopic relocation in the nuclei of skeletal muscles in myotonic dystrophy and sarcopenia

Muscleblind-like 1 (MBNL1) is an alternative splicing factor involved in postnatal development of skeletal muscles and heart in humans and mice, and its deregulation is known to be pivotal in the onset and development of myotonic dystrophy (DM). In fact, in DM patients this protein is ectopically sequestered into intranuclear foci, thus compromising the regulation of the alternative splicing of several genes. However, despite the numerous biochemical and molecular studies, scarce attention has been paid to the intranuclear location of MBNL1 outside the foci, although previous data demonstrated that in DM patients various splicing and cleavage factors undergo an abnormal intranuclear distribution suggestive of impaired RNA processing. Interestingly, these nuclear alterations strongly remind those observed in sarcopenia i.e., the loss of muscle mass and function which physiologically occurs during ageing. On this basis, in the present investigation the ultrastructural localization of MBNL1 was analyzed in the myonuclei of skeletal muscles from healthy and DM patients as well as from adult and old (sarcopenic) mice, in the attempt to elucidate possible changes in its distribution and amount. Our data demonstrate that in both dystrophic and sarcopenic muscles MBNL1 undergoes intranuclear relocation, accumulating in its usual functional sites but also ectopically moving to domains which are usually devoid of this protein in healthy adults. This accumulation/delocalization could contribute to hamper the functionality of the whole splicing machinery, leading to a lower nuclear metabolic activity and, consequently, to a less efficient protein synthesis. Moreover, the similar nuclear alterations found in DM and sarcopenia may account for the similar muscle tissue features (myofibre atrophy, fibre size variability and centrally located nuclei), and, in general, for the aging-reminiscent phenotype observed in DM patients.

Diaminobenzidine photoconversion is a suitable tool for tracking the intracellular location of fluorescently labelled nanoparticles at transmission electron microscopy

Chitosan-based nanoparticles (NPs) deserve particular attention as suitable drug carriers in the field of pharmaceutics, since they are able to protect the encapsulated drugs and/or improve their efficacy by making them able to cross biological barriers (such as the blood-brain barrier) and reach their intracellular target sites. Understanding the intracellular location of NPs is crucial for designing drug delivery strategies. In this study, fluorescently-labelled chitosan NPs were administered in vitro to a neuronal cell line, and diaminobenzidine (DAB) photoconversion was applied to correlate fluorescence and transmission electron microscopy to precisely describe the NPs intracellular fate. This technique allowed to demonstrate that chitosan NPs easily enter neuronal cells, predominantly by endocytosis; they were found both inside membrane-bounded vesicles and free in the cytosol, and were observed to accumulate around the cell nucleus.

Diaminobenzidine photoconversion is a suitable tool for tracking the intracellular location of fluorescently labelled nanoparticles at transmission electron microscopy

Chitosan-based nanoparticles (NPs) deserve particular attention as suitable drug carriers in the field of pharmaceutics, since they are able to protect the encapsulated drugs and/or improve their efficacy by making them able to cross biological barriers (such as the blood-brain barrier) and reach their intracellular target sites. Understanding the intracellular location of NPs is crucial for designing drug delivery strategies. In this study, fluorescently-labelled chitosan NPs were administered in vitro to a neuronal cell line, and diaminobenzidine (DAB) photoconversion was applied to correlate fluorescence and transmission electron microscopy to precisely describe the NPs intracellular fate. This technique allowed to demonstrate that chitosan NPs easily enter neuronal cells, predominantly by endocytosis; they were found both inside membrane-bounded vesicles and free in the cytosol, and were observed to accumulate around the cell nucleus.

Discrete foci containing RNase A are found in nucleoli of HeLa cells after aging in culture

We have studied by means of ultrastructural immunocytochemistry the localization of RNase A in nuclei of HeLa cells in control conditions and following cell ageing in culture. We have found that roundish, electron dense foci, which contain a significant amount of RNase A, can be detected within nucleoli of aged cells. These bodies also contain RNA and lack ribosomal S3 proteins, and may represent either simple storage sites or areas where RNA degradation takes place.

[Clinical, virological and epidemiological aspects of acute B hepatitis in the Catania area (Italy)]

Starting from January 1997 we prospectively evaluated all cases of acute hepatitis B admitted to two of the main Infectious Diseases Units in Catania (eastern Sicily). The survey was extended throughout a 10-year period up to December 2007. Between 1997 and 1999 we observed 21 cases of acute hepatitis B; between 2000 and 2002 18 cases; between 2003 and 2005 22 cases and, finally, 37 cases were reported in the period 2006-2007. We found an increase in acute hepatitis B cases among people aged 26 to 44 years (from 38% in 1997-99 to 70% in 2006-07). A progressive decrease in intravenous drug abuse as a risk factor for acute hepatitis B was also observed (from 61% to 14%) together with a parallel increase in cases due to sexual transmission (from 19% to 56%) and outpatient cosmetic surgical procedures. Mean time to serum HBsAg negativization was longer in the last period (2006-07), with 6 cases out of 37 showing HBsAg persistence beyond 12 months from the clinical onset. Furthermore, in 2006-07 there were 12 cases (42%) of acute hepatitis due to HBV genotypes A and F. In our area, a progressive drop of hepatitis B cases due to intravenous drug abuse occurred, whereas heterosexual and iatrogenic cases increased. Cases due to HBV non-D genotypes may well be related to migration from endemic areas towards Sicily.

Relationships between metabolic syndrome and left ventricular mass in hypertensive patients: does sex matter?

Several studies documented an association between metabolic syndrome (MetS) and left ventricular (LV) hypertrophy. However, only in a few of these studies the impact of MetS on left ventricular mass (LVM) was separately analysed by gender, with conflicting results. The aim of our study was to verify, in a wide sample of essential hypertensive patients, the influence of gender, if any, on the relationship between MetS and LVM. We enrolled 475 non-diabetic subjects (mean age: 46 +/- 11 years), with mild-to-moderate essential hypertension, of whom 40% had MetS, defined on the basis of Adult Treatment Panel III (ATPIII) criteria. All the patients underwent a 24-h ambulatory blood pressure monitoring and an echocardiogram. LVM indexed for height (2.7) (LVMH (2.7)) was significantly (P < 0.001) higher in women with MetS (n=83) than in those without it (n=97; 54+/-17 vs 42+/-11 g m(-2.7)). An equally significant difference in LVMH (2.7) was documented also in male gender between the two groups with (n=105) and without MetS (n=190; 51+/-14 vs 43+/-11 g m(-2.7); P < 0.001). The relationship between MetS and LVMH (2.7) remained statistically significant (P < 0.001) in both sexes, in multiple regression analyses, even after adjustment for potential confounding factors. Our results seem to suggest that the relationship between MetS and LVM is not significantly affected by gender, being LVM increased in both hypertensive women and men with MetS.

Bone regeneration: in vitro evaluation of the behaviour of osteoblast-like MG63 cells placed in contact with polylactic-co-glycolic acid, deproteinized bovine bone and demineralized freeze-dried bone allograft

Insufficient bone density of the alveolar crests, caused by loss of the dental elements, sometimes impedes the primary stability of an integrated bone implant. The techniques of bone regeneration allow to obtain a sufficient quantity of alveolar bone to permit the implant rehabilitation of the edentulous crests. Today several grafting materials are available and they have different characteristics, according to their structure, which influence the different behaviour of the grafting materials to the bone and the implant surface. The aim of this study is to evaluate the interaction between a human osteosarcoma MG63 cell line and three different biomaterials: polylactic-co-glycolic acid (PLAGA), deproteinized bovine bone and demineralised freeze-dried bone allograft (DFDBA). From this study a different behaviour emerges of the osteoblast-like MG63 cells in relation to the sublayer on which these cells were placed in culture. The results of the study, in fact, demonstrate that the most osteoconductive material of the three analysed is the DFDBA, followed by DPBB. On the contrary, the PLGA, because of its roughness, does not seem to represent a valid support for cell growth, and does not encourage any morphologic modification in tumor cells. Furthermore, deproteinized bovine bone shows a differentiating effect which could lead to hypothesise an osteoconductive capacity of this biomaterial. Further studies should be carried out with the aim of explaining the results obtained.

Inverse relationship between ambulatory arterial stiffness index and glomerular filtration rate in arterial hypertension

BACKGROUND

Arterial stiffness and mild-to-moderate renal dysfunction are predictors of cardiovascular (CV) morbidity and mortality. Recently, the ambulatory arterial stiffness index (AASI) has been proposed as a surrogate index of arterial stiffness. It has been associated with an enhanced risk of stroke. The aim of our study was to assess the relationship between AASI and glomerular filtration rate (GFR) in a group of hypertensive patients with no CV complications.

METHODS

A total of 143 untreated hypertensive subjects (mean age: 44 +/- 12 years; men 57%), with serum creatinine <1.5 mg/dl, were enrolled. AASI was calculated as one minus the regression slope of diastolic on systolic blood pressure (BP) obtained by individual 24-h BP recordings. GFR was computed from the scintigraphic determination of the technetium-99m diethylenetriaminepentaacetic acid uptake within the kidneys, by the Gates' method.

RESULTS

Hypertensive patients with AASI above the median value (n = 71) had lower GFR than those with AASI below the median (n = 72) (98.3 +/- 31 vs. 122.4 +/- 32 ml/min/1.73 m(2); P < 0.001). This difference held even after adjustment for age and gender. The linear regression analysis disclosed a significant inverse correlation between GFR and AASI (r = -0.30; P < 0.001), that was replicated (beta = -0.19; P = 0.02) in a multiple regression model including, as independent variables (besides AASI), age, gender, high-density lipoprotein cholesterol, body mass index, 24-h pulse pressure (PP) and nocturnal reduction in BP.

CONCLUSIONS

AASI is inversely related to GFR in arterial hypertension. This may help to explain the increased CV risk associated with mild-to-moderate renal dysfunction.