Physical activity habits prevent psychological distress in female academic students: The multiple mediating role of physical and psychosocial parameters

Background

Psychological distress is recognised as the most common mental health difficulty in emerging adult (18-to-24-year-old) female academic students. This study aimed to test a novel model positing physical activity habits as a protective factor for psychological distress through the mediating role of physical and psychological parameters. Adherence to the Mediterranean diet and self-reported physical health status were included as physical parameters. Self-reported psychological health status and time spent on leisure activities were the psychological parameters considered.

Method

Data were collected between April and May 2021. Correlation analyses and a multiple mediation model were computed on 411 online questionnaires filled out by 18-to-24-year-old female students from the University of blind (Italy).

Results

The multiple indirect effects were significant (β = -0.088; p < 0.001). This means that physical activity habits reduce psychological distress through high adherence to the Mediterranean diet, a good self-assessment of one's physical and psychological health status, and more time spent on leisure activities outdoors, with friends, and with family members.

Conclusions

Results show that academic policies should be adopted so as to design physical activity programmes that may improve the students' healthy behaviours and social interactions, which, in turn, mitigate the detrimental effects of psychological distress.

Genetic and functional evidence for gp130/IL6ST-induced transient receptor potential ankyrin 1 upregulation in uninjured but not injured neurons in a mouse model of neuropathic pain

ABSTRACT

Peripheral nerve injuries result in pronounced alterations in dorsal root ganglia, which can lead to the development of neuropathic pain. Although the polymodal mechanosensitive transient receptor potential ankyrin 1 (TRPA1) ion channel is emerging as a relevant target for potential analgesic therapies, preclinical studies do not provide unequivocal mechanistic insight into its relevance for neuropathic pain pathogenesis. By using a transgenic mouse model with a conditional depletion of the interleukin-6 (IL-6) signal transducer gp130 in Nav1.8 expressing neurons (SNS-gp130-/-), we provide a mechanistic regulatory link between IL-6/gp130 and TRPA1 in the spared nerve injury (SNI) model. Spared nerve injury mice developed profound mechanical hypersensitivity as indicated by decreased withdrawal thresholds in the von Frey behavioral test in vivo, as well as a significant increase in mechanosensitivity of unmyelinated nociceptive primary afferents in ex vivo skin-nerve recordings. In contrast to wild type and control gp130fl/fl animals, SNS-gp130-/- mice did not develop mechanical hypersensitivity after SNI and exhibited low levels of Trpa1 mRNA in sensory neurons, which were partially restored by adenoviral gp130 re-expression in vitro. Importantly, uninjured but not injured neurons developed increased responsiveness to the TRPA1 agonist cinnamaldehyde, and neurons derived from SNS-gp130-/- mice after SNI were significantly less responsive to cinnamaldehyde. Our study shows for the first time that TRPA1 upregulation is attributed specifically to uninjured neurons in the SNI model, and this depended on the IL-6 signal transducer gp130. We provide a solution to the enigma of TRPA1 regulation after nerve injury and stress its significance as an important target for neuropathic pain disorders.

Au(iii)-Proline derivatives exhibiting selective antiproliferative activity against HepG2/SB3 apoptosis-resistant cancer cells

This paper deals with the combination of a proline-based moiety with biologically active gold centers in the oxidation states +1 and +3. In particular, six Au(i)/(iii)-proline dithiocarbamato (DTC) complexes with general formulae [Au(DTC)₂] and [Au^IIIX₂(DTC)] (X = Cl, Br) are reported here. After the synthesis of the ligand and the complexes, all derivatives were characterized via several techniques and tested for their stability in DMSO/water media. This study was focused on the demonstration of a peculiar behavior of Au(iii)-DTC species in solution. Finally, the complexes were screened for their antiproliferative activity against 2 human cancer cell lines, namely HepG2 and HepG2/SB3, taken as models of hepatocellular carcinoma. The latter, chosen for its aggressiveness due to the upregulation of the anti-apoptotic protein SerpinB3, was selectively inhibited in terms of growth by some Au(iii)-DTC complexes.

Impaired mechanical, heat, and cold nociception in a murine model of genetic TACE/ADAM17 knockdown

TNF-α-converting enzyme, a member of the ADAM (A disintegrin and metalloproteinase) protease family and also known as ADAM17, regulates inflammation and regeneration in health and disease. ADAM17 targets are involved in pain development and hypersensitivity in animal models of inflammatory and neuropathic pain. However, the role of ADAM17 in the pain pathway is largely unknown. Therefore, we used the hypomorphic ADAM17 (ADAM17^ex/ex) mouse model to investigate the importance of ADAM17 in nociceptive behavior, morphology, and function of primary afferent nociceptors. ADAM17^ex/ex mice were hyposensitive to noxious stimulation, showing elevated mechanical thresholds as well as impaired heat and cold sensitivity. Despite these differences, skin thickness and innervation were comparable to controls. Although dorsal root ganglia of ADAM17^ex/ex mice exhibited normal morphology of peptidergic and nonpeptidergic neurons, a small but significant reduction in the number of isolectin β-4–positive neurons was observed. Functional electrical properties of unmyelinated nociceptors showed differences in resting membrane potential, afterhyperpolarization, and firing patterns in specific subpopulations of sensory neurons in ADAM17^ex/ex mice. However, spinal cord morphology and microglia activity in ADAM17^ex/ex mice were not altered. Our data suggest that ADAM17 contributes to the processing of painful stimuli, with a complex mode of action orchestrating the function of neurons along the pain pathway.—Quarta, S., Mitrić, M., Kalpachidou, T., Mair, N., Schiefermeier-Mach, N., Andratsch, M., Qi, Y., Langeslag, M., Malsch, P., Rose-John, S., Kress, M. Impaired mechanical, heat, and cold nociception in a murine model of genetic TACE/ADAM17 knockdown.

Synthesis, chemical characterization and cancer cell growth-inhibitory activities of Cu(ii) and Ru(iii) aliphatic and aromatic dithiocarbamato complexes

The effects mediated by different cyclic dithiocarbamic ligands on three classes of antiproliferative coordination compounds were studied.

Sphingosine-1-Phosphate and the S1P3 Receptor Initiate Neuronal Retraction via RhoA/ROCK Associated with CRMP2 Phosphorylation

The bioactive lipid sphingosine-1-phosphate (S1P) is an important regulator in the nervous system. Here, we explored the role of S1P and its receptors in vitro and in preclinical models of peripheral nerve regeneration. Adult sensory neurons and motor neuron-like cells were exposed to S1P in an in vitro assay, and virtually all neurons responded with a rapid retraction of neurites and growth cone collapse which were associated with RhoA and ROCK activation. The S1P₁ receptor agonist SEW2871 neither activated RhoA or neurite retraction, nor was S1P-induced neurite retraction mitigated in S1P₁-deficient neurons. Depletion of S1P₃ receptors however resulted in a dramatic inhibition of S1P-induced neurite retraction and was on the contrary associated with a significant elongation of neuronal processes in response to S1P. Opposing responses to S1P could be observed in the same neuron population, where S1P could activate S1P₁ receptors to stimulate elongation or S1P₃ receptors and retraction. S1P was, for the first time in sensory neurons, linked to the phosphorylation of collapsin response-mediated protein-2 (CRMP2), which was inhibited by ROCK inhibition. The improved sensory recovery after crush injury further supported the relevance of a critical role for S1P and receptors in fine-tuning axonal outgrowth in peripheral neurons.

Ablation of Sphingosine 1-Phosphate Receptor Subtype 3 Impairs Hippocampal Neuron Excitability In vitro and Spatial Working Memory In vivo

Understanding the role of the bioactive lipid mediator sphingosine 1-phosphate (S1P) within the central nervous system has recently gained more and more attention, as it has been connected to major diseases such as multiple sclerosis and Alzheimer's disease. Even though much data about the functions of the five S1P receptors has been collected for other organ systems, we still lack a complete understanding for their specific roles, in particular within the brain. Therefore, it was the aim of this study to further elucidate the role of S1P receptor subtype 3 (S1P₃) in vivo and in vitro with a special focus on the hippocampus. Using an S1P₃ knock-out mouse model we applied a range of behavioral tests, performed expression studies, and whole cell patch clamp recordings in acute hippocampal slices. We were able to show that S1P₃ deficient mice display a significant spatial working memory deficit within the T-maze test, but not in anxiety related tests. Furthermore, S1p3 mRNA was expressed throughout the hippocampal formation. Principal neurons in area CA3 lacking S1P₃ showed significantly increased interspike intervals and a significantly decreased input resistance. Upon stimulation with S1P CA3 principal neurons from both wildtype and S1P3−/− mice displayed significantly increased evoked EPSC amplitudes and decay times, whereas rise times remained unchanged. These results suggest a specific involvement of S1P₃ for the establishment of spatial working memory and neuronal excitability within the hippocampus.

Sphingosine 1-phosphate to p38 signaling via S1P1 receptor and Gαi/o evokes augmentation of capsaicin-induced ionic currents in mouse sensory neurons

The perception of painful thermal stimuli by sensory neurons is largely mediated by TRPV1. Upon tissue injury or inflammation, S1P is secreted by thrombocytes as part of an inflammatory cocktail, which sensitizes nociceptive neurons towards thermal stimuli. S1P acts on G-protein coupled receptors that are expressed in sensory neurons and sensitize TRPV1 channels towards thermal stimuli. In this study, the S1P mediated signaling pathway required for sensitization of TRPV1 channels was explored.The capsaicin induced peak inward current (ICAPS) of sensory neurons was significantly increased after S1P stimulation within minutes after application. The potentiation of ICAPS resulted from activation of Gαi through G-protein coupled receptors for S1P. Consequently, Gαi led to a signaling cascade, involving phosphoinositide-3-kinase (PI3K) and protein kinase C, which augmented ICAPS in nociceptive neurons. The S1P1 receptor agonist SEW2871 resulted in activation of the same signaling pathway and potentiation of ICAPS. Furthermore, the mitogen-activated protein kinase p38 was phosphorylated after S1P stimulation and inhibition of p38 signaling by SB203580 prevented the S1P-induced ICAPS potentiation. The current data suggest that S1P sensitized ICAPS through G-protein coupled S1P1 receptor activation of Gαi-PI3K-PKC-p38 signaling pathway in sensory neurons.

Exercise tolerance in systemic sclerosis patients without pulmonary impairment: correlation with clinical variables

OBJECTIVES

In systemic sclerosis (SSc) patients pulmonary vasculopathy (PV) is present in the early stage of disease and impairs dilation of affected pulmonary blood vessels, impeding pulmonary blood flow during exercise. Abnormal gas exchange findings were early investigated by cardiopulmonary exercise test (CPET).

METHODS

A total of 34 female and 6 male [median age 49 (20-63) years] SSc patients with normal chest imaging and pulmonary function tests were enrolled. Twenty healthy controls age and sex matched [16 female and 4 male; median age 51 (35-73) years] were also recruited. All subjects underwent a full clinical examination, including a nailfold video capillaros copy (NVC). An incremental symptom-limited CPET was performed with estimation of minute ventilation (VE), workload (WR), peak oxygen uptake (pVO₂2), and ventilatory efficiency (VE/VCO2 slope).

RESULTS

A reduced exercise tolerance (pVO₂<80% of predicted) was documented in 18 out of 40 subjects (45%). Six out of 18 patients with a reduced exercise tolerance showed indirect signs of ventilation perfusion mismatch (VE/ VCO2 slope >34). Patients with digital ulcers (DUs) history showed VE/VCO₂slope values significantly higher [31.4 (18-39.6)] than in patients without DUs history [26.9 (22-29.4)] (p<0.0001). VE/VCO₂slope values also significantly differed between the three capillaroscopic groups: early [26.3 (18-29.4)], active [28 (26.8-39.6)], and late [32.9 (22.4-39)] (p<0.0001). A positive correlation was found between the VE/ VCO₂slope and both Disease Activity Index (p<0.0001, r=0.59) and Disease Severity Scale (p<0.0001, r=0.73).

CONCLUSIONS

In SSc patients without evidence of pulmonary and cardiac involvement, CPET might be useful in disclosing an early PV.

Safety and infectious prophylaxis of intravenous immunoglobulin in elderly patients with membranous nephropathy

A variety of infections has been recognized as an important cause of morbidity and mortality in patients with nephrotic syndrome, and membranous nephropathy is a common cause of this in the elderly. The reasons for infection risk are due to oedema complications, urinary loss of factor B and D of the alternative complement pathway, cellular immunity, granulocyte chemotaxis, hypogammaglobulinemia with serum IgG levels below 600 mg/dL, and secondary effects of immunosuppressive therapy. Many different prophylactic interventions have been used for reducing the risks of infection in these patients but recommendations for routine use are still lacking. We report two membranous nephropathy cases in the elderly in which Intravenous immunoglobulin were useful in long-term infectious prophylaxis, showing safety in renal function. During immunosuppressant therapy in membranous nephropathy, intravenous immunoglobulin without sucrose are a safe therapeutic option as prophylaxis in those patients with nephrotic syndrome and IgG levels below 600 mg/dL. The long-term goal of infection prevention in these patients is to reduce mortality, prolong survival and improve quality of life.

Sexual Distress, Sexual Dysfunction and Relationship Quality in Women with Systemic Sclerosis: Correlation with Clinical Variables

To assess the rate of sexual distress, sexual dysfunction and relationship quality and their association with clinical variables in women with systemic sclerosis (SSc), 102 sexually active women with SSc were recruited. Sexual distress, sexual dysfunction and dissatisfaction with relationship quality were investigated by Female Sexual Distress Scale Revised (FSDS-R), Female Sexual Function Index (FSFI) and Dyadic Adjustment Scale (DAS), respectively. The patients underwent medical examinations and nailfold videocapillaroscopy (NVC). Of the 102 patients, 37 (36%) reported sexual distress with FSDS-R score >11, 45 (44%) had sexual dysfunction with FSFI score <19 and 49 (48%) were not satisfied with relationship quality with DAS score <100. There was a negative correlation (p<0.001, R= −0.30) between FSDS-R and FSFI. No correlation was found between FSDS-R and DAS. FSFI showed a positive correlation with DAS (p<0.0001, R= 0.36). Age correlated negatively (p<0.05, R= −0.26) with FSFI, while FSDS-R and DAS did not correlate (p>0.05) with age. SSc women with digital ulcers (DU) had a reduction of FSFI and DAS compared with women without DU. In patients with late capillaroscopic pattern, mean value of FSFI was significantly lower than the other two capillaroscopic patterns. DAS decreased with progression of capillaroscopic damage. In a high percentage of women with SSc FSDS-R was increased, while FSFI and DAS were reduced. Age correlated negatively with FSFI, while skin score showed a negative correlation with DAS. Digital vascular damage negatively influenced FSFI and DAS.

Doppler Ultrasound Study of Penis in Men with Systemic Sclerosis: A Correlation with Doppler Indices of Renal and Digital Arteries

Erectile dysfunction (ED) prevalence in male systemic sclerosis (SSc) is high and its pathogenesis is unclear. The aim of the study is to assess correlation between Doppler ultrasound indices of penis and kidneys or digital arteries in male systemic sclerosis. Fourteen men with systemic sclerosis were enrolled in this study. Erectile function was investigated by the International Index of Erectile Function-5. Peak systolic velocity, end diastolic velocity, resistive index, pulsative index, and systolic/diastolic ratio were measured on the cavernous arteries at the peno-scrotal junction in the flaccid state, on the interlobar artery of both kidneys and all ten proper palmar digital arteries. Ten (71%) patients have an International Index of Erectile Function-5 <21. Reduction of penis peak systolic velocity was observed in all SSc subjects. Doppler indices of cavernous arteries correlate with the International Index of Erectile Function-5. The renal and digital arteries resistive index demonstrated a good correlation (p<0.0001) with International Index of Erectile Function-5. A positive correlation exists between penis and kidney arteries Doppler indices: end diastolic velocity (p<0.05, r=0.54), resistive index (p<0.0001, r=0.90), systolic/diastolic ratio (p<0.01, r=0.69). A positive correlation was observed between penis and digital arteries Doppler indices: peak systolic velocity (p<0.01, r=0.68), end diastolic velocity (p<0.01, r=0.75), resistive index (p<0.001, r=0.79), systolic/diastolic ratio (p<0.05, r=0.59). A correlation exists between arterial impairment of penis and renal or digital arteries.

Oncostatin M induces heat hypersensitivity by gp130-dependent sensitization of TRPV1 in sensory neurons

Oncostatin M (OSM) is a member of the interleukin-6 cytokine family and regulates eg. gene activation, cell survival, proliferation and differentiation. OSM binds to a receptor complex consisting of the ubiquitously expressed signal transducer gp130 and the ligand binding OSM receptor subunit, which is expressed on a specific subset of primary afferent neurons. In the present study, the effect of OSM on heat nociception was investigated in nociceptor-specific gp130 knock-out (SNS-gp130^-/-) and gp130 floxed (gp130^fl/fl) mice.

Subcutaneous injection of pathophysiologically relevant concentrations of OSM into the hind-paw of C57BL6J wild type mice significantly reduced paw withdrawal latencies to heat stimulation. In contrast to gp130^fl/fl mice, OSM did not induce heat hypersensitivity in vivo in SNS-gp130^-/- mice. OSM applied at the receptive fields of sensory neurons in in vitro skin-nerve preparations showed that OSM significantly increased the discharge rate during a standard ramp-shaped heat stimulus. The capsaicin- and heat-sensitive ion channel TRPV1, expressed on a subpopulation of nociceptive neurons, has been shown to play an important role in inflammation-induced heat hypersensitivity. Stimulation of cultured dorsal root ganglion neurons with OSM resulted in potentiation of capsaicin induced ionic currents. In line with these recordings, mice with a null mutation of the TRPV1 gene did not show any signs of OSM-induced heat hypersensitivity in vivo.

The present data suggest that OSM induces thermal hypersensitivity by directly sensitizing nociceptors via OSMR-gp130 receptor mediated potentiation of TRPV1.

Genetic evidence for an essential role of neuronally expressed IL-6 signal transducer gp130 in the induction and maintenance of experimentally induced mechanical hypersensitivity in vivo and in vitro

Tenderness and mechanical allodynia are key symptoms of malignant tumor, inflammation and neuropathy. The proinflammatory cytokine interleukin-6 (IL-6) is causally involved in all three pathologies. IL-6 not only regulates innate immunity and inflammation but also causes nociceptor sensitization and hyperalgesia. In general and in most cell types including immune cells and sensory neurons, IL-6 binds soluble μ receptor subunits which heteromerizes with membrane bound IL-6 signal transducer gp130. In the present study, we used a conditional knock-out strategy to investigate the importance of signal transducer gp130 expressed in C nociceptors for the generation and maintenance of mechanical hypersensitivity. Nociceptors were sensitized to mechanical stimuli by experimental tumor and this nociceptor sensitization was preserved at later stages of the pathology in control mice. However, in mice with a conditional deletion of gp130 in Nav1.8 expressing nociceptors mechanical hypersensitivity by experimental tumor, nerve injury or inflammation recovery was not preserved in the maintenance phase and nociceptors exhibited normal mechanical thresholds comparable to untreated mice. Together, the results argue for IL-6 signal transducer gp130 as an essential prerequisite in nociceptors for long-term mechanical hypersensitivity associated with cancer, inflammation and nerve injury.

Genetic evidence for involvement of neuronally expressed S1P₁ receptor in nociceptor sensitization and inflammatory pain

Sphingosine-1-phosphate (S1P) is a key regulator of immune response. Immune cells, epithelia and blood cells generate high levels of S1P in inflamed tissue. However, it is not known if S1P acts on the endings of nociceptive neurons, thereby contributing to the generation of inflammatory pain. We found that the S1P₁ receptor for S1P is expressed in subpopulations of sensory neurons including nociceptors. Both S1P and agonists at the S1P₁ receptor induced hypersensitivity to noxious thermal stimulation in vitro and in vivo. S1P-induced hypersensitivity was strongly attenuated in mice lacking TRPV1 channels. S1P and inflammation-induced hypersensitivity was significantly reduced in mice with a conditional nociceptor-specific deletion of the S1P₁ receptor. Our data show that neuronally expressed S1P₁ receptors play a significant role in regulating nociceptor function and that S1P/S1P₁ signaling may be a key player in the onset of thermal hypersensitivity and hyperalgesia associated with inflammation.

Squamous cell carcinoma antigen-1 (SERPINB3) polymorphism in chronic liver disease

BACKGROUND

The serpin squamous cell carcinoma antigen (SCCA, SERPINB3) has been found over-expressed in primary liver cancer and at lower extent in cirrhosis and chronic hepatitis. A novel SCCA-1 variant (SCCA-PD), presenting a single mutation in the reactive centre (Gly351Ala), has been recently identified (rs3180227).

AIM

To explore SCCA-1 polymorphism in patients with HCV infection as single etiologic factor and different extent of liver disease.

METHODS

One hundred and fourty-eight patients with chronic HCV infection (45 chronic hepatitis, 53 cirrhosis, 50 HCC) and 50 controls were evaluated. SCCA-1 polymorphism was studied by restriction fragment length polymorphism and confirmed randomly by direct sequencing. Circulating SCCA-IgM complex was determined by ELISA.

RESULTS

SCCA-PD was detected with higher frequency in cirrhotic patients (45.3%, odds ratio=2.62; 95%CI 1.13-6.10, p=0.038) than in patients with chronic hepatitis or in controls (24.4% and 24%, respectively). Intermediate figures were found in hepatocarcinoma (36.0%). SCCA-IgM in serum was lower in patients carrying SCCA-PD than in wild type patients and the difference was statistically significant in cirrhotic patients (mean+/-S.D.=117.45+/-54.45 U/ml vs. 268.52+/-341.27 U/ml, p=0.026).

CONCLUSIONS

The newly identified SCCA-PD variant was more frequently found in liver cirrhosis, suggesting that patients carrying this polymorphism are more prone to develop progressive liver fibrosis.

Monitoring SCCA-IgM complexes in serum predicts liver disease progression in patients with chronic hepatitis

About 30% of the patients with chronic hepatitis develop a progressive liver disease and one of the most intriguing issues is the detection of noninvasive markers for fibrosis stage and disease progression. High levels of squamous cell carcinoma antigen (SCCA)-immunoglobulin M (IgM) are detectable in hepatocellular carcinoma and their increase in cirrhotic patients can predict tumour development. As SCCA-IgM can also be detectable at low percentages in patients with chronic hepatitis, the aim of this study was to assess SCCA-IgM complexes in relation to disease outcome in this group of patients. An ELISA assay was used to determine the presence of SCCA-IgM in 188 patients with chronic hepatitis and in 100 controls. An additional serum sample was available after a median period of 6 years in 57 untreated patients: these patients were subdivided in group A, including eight patients with a fibrosis score increase > or =2 in a second liver biopsy and group B, including 49 patients without fibrosis progression during a similar follow up. SCCA-IgM complexes were detectable in 63 of 188 (33%) patients but in none of the controls. A significant increase of SCCA-IgM levels over time was observed in patients with fibrosis progression (mean +/- SD: 117 +/- 200 U/mL/year), but not in those without histologic deterioration (mean +/- SD: -8.8 +/- 31 U/mL/year, P < 0.0001). In conclusion, monitoring SCCA-IgM levels over time appears a useful approach to identify patients with chronic hepatitis at higher risk for cirrhosis development.

Hepatotropic viruses: new insights in pathogenesis and treatment

Hepatitis B virus (HBV) can be detected in peripheral blood mononuclear cells (PBMCs), mainly B lymphocytes and monocytes. The frequency of PBMC infection is higher in patients with ongoing HBV replication, but can persist for years after the complete resolution of an acute episode of hepatitis B. Infected PBMCs can act as reservoirs for the cell-to-cell transmission of the virus, and vertical transmission studies indicate that the HBV-infected PBMCs of mothers may act as a vector for intrauterine HBV infection. Recent data evaluated whether HBV occult infection could co-operate with HCV infection in the pathogenesis of mixed cryoglobulinemia (MC) and lymphoma and/or whether it may be implicated in the pathogenesis of MC and malignant diseases -B-cell non-Hodgkin's lymphoma (NHL) also independently from HCV. The treatment of chronic HBeAg-negative hepatitis B is intended to ensure the long-term suppression of HBV replication with the aim of halting the progression of liver damage and preventing the development of liver-related complications. This can be done by means of short-term "curative" treatment or long-term "suppressive" therapy. The first approach requires a 48-week course of peginterferon, which controls viral replication (HBV DNA <10.000 copies/ml) in 20-30% of patients; the second requires the long-term (possibly lifetime) administration of nucleoside and/or nucleotide analogues. As none of the currently available drugs alone suppresses viral replication (HBV DNA <200 copies/ml) for five years in all patients, some require a rescue therapy based on the addition of a non-cross-resistant drug, which should be given as early as possible ("on demand" combination therapy). However, the currently available anti-HBV analogues can easily suppress HBV replication for five years in most HBeAg-negative patients. As both strategies have their pros and cons, the best approach needs to be carefully evaluated on an individual basis.

Haeme oxygenase mediates hyporeactivity to phenylephrine in the mesenteric vessels of cirrhotic rats with ascites

BACKGROUND AND AIMS

Haeme oxygenase could play a role in the pathogenesis of arterial vasodilation in cirrhosis. The aim of this study was to verify the role of haeme oxygenase in the hyporesponsiveness to phenylephrine of small mesenteric arteries in rats with CCl(4) induced cirrhosis, with and without ascites.

METHODS

Pressurised small resistance mesenteric arteries were challenged with increasing doses of phenylephrine. Dose-response curves were evaluated under basal conditions, after inhibition of haeme oxygenase with chromium-mesoporphyrin, after inhibition of nitric oxide synthase (NOS) with N(G)-nitro-L-arginine-methyl-ester (L-NAME), and then after inhibition of both NOS and haeme oxygenase. Haeme oxygenase protein expression was also analysed.

RESULTS

Twenty six control rats and 35 rats with cirrhosis (17 with and 18 without ascites) were studied. Response to phenylephrine was lower in non-ascitic and ascitic cirrhosis than in controls. Chromium-mesoporphyrin increased the response to phenylephrine only in ascitic cirrhosis (p<0.001). L-NAME increased the response to phenylephrine in controls (p<0.001) and in ascitic and non-ascitic cirrhosis (p = 0.002, p<0.001, respectively) but the final response in non-ascitic cirrhosis was similar to that of control rats while it remained impaired in ascitic cirrhosis. Addition of chromium-mesoporphyrin to L-NAME improved the response to phenylephrine in ascitic cirrhosis (p<0.01), with final values not different from those of the other two groups. Protein expression of the inducible isoform of haeme oxygenase was increased in the mesenteric vessels of cirrhotic rats.

CONCLUSION

Haeme oxygenase mediates hyporeactivity to phenylephrine in the mesenteric vessels of experimental cirrhosis with ascites. NOS plays a major role only in the first stage of the disease.

Prenatal diagnosis of symptomatic congenital cytomegalovirus infection

OBJECTIVE

The aim of this study was to evaluate whether the amniotic viral load of mothers with primary cytomegalovirus infection correlate with fetal or neonatal outcomes.

STUDY DESIGN

Sixty-eight of 138 pregnant women with primary infection defined by immunoglobulin G seroconversion or the presence of immunoglobulin M with low immunoglobulin G avidity accepted amniocentesis. Polymerase chain reaction and quantitative polymerase chain reaction were used to detect amniotic fluid cytomegalovirus. Cytomegalovirus infection in neonates was determined by means of urinary viral isolation during the first week after birth or the histologic examination of tissue from aborted fetuses.

RESULTS

Cytomegalovirus infection was found in 16 fetuses and neonates (23%), 5 of whom had symptoms. Quantitative polymerase chain reaction showed that the presence of >/=10(3) genome equivalents predicted mother-child infection with 100% probability; >/=10(5) genome equivalents predicted the development of a symptomatic infection.

CONCLUSION

Fewer than expected cytomegalovirus-infected fetuses are at risk for development of cytomegaloviral disease, and this fact may be useful in counseling pregnant women with primary cytomegalovirus infection.

The antiproliferative effect of beta-carotene requires p21waf1/cip1 in normal human fibroblasts

In normal human fibroblasts, beta-carotene induces a cell-cycle delay in the G1 phase independent of its provitamin A activity via a mechanism not yet elucidated. In this study we provide biochemical evidence showing that delayed progression through the G1 phase occurs concomitantly with: an increase in both nuclear-bound and total p21waf1/cip1 protein levels; an increase in the amount of p21waf1/cip1 associated with cdk4; the inhibition of cyclin D1-associated cdk4 kinase activity; and a reduction in the levels of hyperphosphorylated forms of retinoblastoma protein, and particularly, in phosphorylated Ser780. The role of p21waf1/cip1 in the antiproliferative effect of the carotenoid was further supported by genetic evidence that neither changes in cell-cycle progression nor in the phosphorylation status of retinoblastoma protein were observed in p21waf1/cip1-deficient human fibroblasts treated with beta-carotene. These results clearly demonstrate that p21waf1/cip1 is involved directly in the molecular pathway by which beta-carotene inhibits cell-cycle progression.

The cyclin-dependent kinase inhibitors olomoucine and roscovitine arrest human fibroblasts in G1 phase by specific inhibition of CDK2 kinase activity

The specificity and the temporal location of cell cycle arrest induced by the cyclin-dependent kinase (CDK) inhibitors olomoucine and roscovitine were investigated in normal human fibroblasts. Effects on the cell cycle were compared with those induced by the kinase inhibitor staurosporine, which arrests normal cells in early G1 phase by acting upstream of CDK2. Consistent with their in vitro activity, olomoucine and roscovitine, but not the related compound iso-olomoucine, induced a dose-dependent arrest in G1 phase. Following removal of CDK inhibitors, cells resumed cycle progression entering S phase with a kinetics faster than staurosporine-treated samples. Cellular levels of PCNA, cyclin D1, and cyclin E were not affected by the CDK inhibitors. In contrast, staurosporine significantly reduced the levels of these proteins, as determined by immunocytometry and Western blot analysis. Cyclin A was detectable only in some cells remaining in the G2 + M compartment of samples treated with CDK inhibitors, but not in samples treated with staurosporine. Significant reduction in the hyperphosphorylated forms of retinoblastoma protein was found in samples treated with CDK inhibitors, while only hypophosphorylated forms were observed in staurosporine-treated samples. Concomitantly, CDK2, but not CDK4, activity immunoprecipitated from cells treated with olomoucine or roscovitine was markedly inhibited. These results suggest that in normal cells, CDK2 kinase activity is the specific target of olomoucine and roscovitine.

Effects of beta-carotene and alpha-tocopherol on photogenotoxicity induced by 8-methoxypsoralen: the role of oxygen

The protective effect of beta-carotene (beta-C) and alpha-tocopherol (alpha-T), singularly and in equimolar mixtures, toward the photomutagenicity induced by 8-methoxypsoralen (8-MOP), at different oxygen partial pressure (pO2), was evaluated in two different experimental models: Salmonella typhimurium TA102 and Saccharomyces cerevisiae D7. After phototreatment with 8-MOP, the results show a lethal effect under hypoxic conditions in both experimental model systems, an increase in revertants associated to the pO2 increase in S. typhimurium TA102, and a decrease in revertants and convertants associated to the pO2 increase in S. cerevisiae D7. In S. typhimurium TA102, in atmospheric condition, beta-C and alpha-T (1.86 or 18.6 microM) show a protective effect only at the higher dosage. Alpha-T was more protective than beta-C. The equimolar mixtures show an antimutagenic effect at both dosage used with a synergistic effect at lower dosage and an additive antimutagenic activity at higher dosage. An inhibition of the spontaneous mutagenicity by mixtures at higher dosage was also observed. The results obtained in S. typhimurium TA102 show an antimutagenic effects of beta-C, alpha-T and their mixture at 190 mmHg pO2, confirming the data obtained in air condition. At 380 mmHg pO2, alpha-T and the mixture show a significant antimutagenic activity; at 570 mmHg pO2, only alpha-T is protective. At 760 mmHg pO2, no protective effect was observed by the two antioxidants, and beta-C increases the photomutagenicity induced by 8-MOP. In S. cerevisiae D7 a protective effect was only observed at 380 mmHg pO2 with the mixture. No antigenotoxic effect was found in the other experimental conditions, even if the uptake of the two antioxidants was confirmed by HPLC. Our results underline the role of oxygen in the photomutagenicity induced by 8-MOP and in the antimutagenic activity of beta-C and alpha-T. This is the first report confirming in a cellular experimental model the data obtained in some chemical systems: the protective effect of beta-C only at low pO2 and the synergistic effect of mixture of beta-C and alpha-T.