Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

Rearing in captivity affects spermatogenesis and sperm quality in greater amberjack, Seriola dumerili (Risso, 1810)

The greater amberjack, (Risso, 1810), is a promising candidate for the diversification of European aquaculture production, but inconsistent reproduction in captivity prevents commercial production. Recent studies showed that greater amberjack confined in sea cages exhibited scarce gonad development and early interruption of gametogenic activity during the reproductive season. The aim of the present study was to improve our understanding of the observed impairment of spermatogenesis. Adult wild and captive-reared males were sampled during 3 different phases of the reproductive cycle: early gametogenesis (EARLY; late April to early May), advanced gametogenesis (ADVANCED; late May to early June), and spawning (SPAWNING; late June to July). Spermatogonial stem cells and proliferating germ cells were identified through the immunohistochemical localization of and proliferating cell nuclear antigen, respectively. Apoptotic germ cells were identified throughout the terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end labeling method. Sperm quality of captive-reared fish was evaluated using computer-assisted sperm analysis. Captive-reared males exhibited seminiferous lobules of a smaller diameter, a precocious and progressive decrease of spermatogonial mitosis, and a high level of apoptosis at the beginning of the reproductive season, concomitant with a many-fold higher 17β-estradiol plasma concentration. The motile spermatozoa percentage of captive greater amberjack was lower than in other teleosts, and a drastic decrease of spermatozoa motility duration, velocity, and ATP content occurred along the reproductive season. An abnormal increase of sperm concentration as well as an increase of dead spermatozoa occurred during the SPAWNING phase, probably because of lack of sperm hydration and ejaculation and consequent sperm ageing. The present study demonstrates the extreme susceptibility of greater amberjack to rearing stress and underscores the need for improvement of the rearing and handling procedures to ameliorate gametogenesis dysfunctions in commercial aquaculture production.

Hepatitis C Virus Infection and Diabetes Mellitus in End-Stage Renal Disease: Evidence of a Negative Association

Epidemiological studies have implicated hepatitis C virus (HCV) infection in the pathogenesis of diabetes mellitus (DM) both in the population as a whole and after solid organ transplantation. Whether this association exists in patients with end-stage renal disease (ESRD) undergoing dialysis is unclear. The aim of this study is to investigate the relationship between HCV and DM in a large group (n = 742) of patients with ESRD from Europe and North America. The presence of diabetes was ascertained by using American Diabetes Association guidelines based on fasting glucose measurement and medication history. Presence of HCV infection was assessed by serum testing for anti-HCV antibodies. The prevalence of anti-HCV antibody positive patients was 15% (112/742); the frequency of DM was higher among anti-HCV positive than -HCV negative patients but the difference did not approach statistical significance, 32% (36/112) vs 29.5% (186/630). The frequency of patients with diabetic nephropathy was not higher in anti-HCV positive than -negative patients; 21.4% (24/112) vs 23.3% (147/630), NS. Logistic regression model showed an independent and significant link between anti-HCV seropositive status and raised GPT (P = 0.032), male gender (P = 0.0462), positive history of prior renal transplant (P = 0.0006), and longer time on dialysis (P = 0.00001). In summary, no link between anti-HCV antibody and DM occurred in this ESRD population; there was no association between rate of anti-HCV antibody and diabetic nephropathy.

Interferon Therapy for HCV-Associated Glomerulonephritis: Meta-Analysis of Controlled Trials

Background

A relationship between hepatitis C virus (HCV) infection and chronic glomerulonephritis (GN) has been asserted on the grounds of epidemiological and experimental data. Although this suggests a role for an antiviral approach to HCV-associated GN instead of the more conventional immunosuppressive (or supportive) therapy, the optimal management of HCV-related glomerulonephritis remains controversial.

Objective

To compare antiviral with immunosuppressive therapy for HCV-associated GN.

Design

Meta-analysis of controlled clinical trials (CCTs) of the two treatments (antiviral versus immunosuppressive) of HCV-associated GN.

Methods

We used the fixed or random effects model of DerSimonian and Laird, with heterogeneity and sensitivity analyses. The rate of proteinuria and serum creatinine decrease after therapy for HCV-associated GN were regarded as the most reliable outcome end-points.

Results

We identified six studies involving 145 unique patients with HCV-associated GN. Pooling of study results demonstrated that proteinuria decreased more commonly after IFN than corticosteroid therapy (OR 1.92 (95% CI, 0.39; 9.57), NS), P-test for heterogeneity, 0.06 (I2=52.9%). In a sensitivity analysis including only CCTs using standard IFN-doses, OR was 3.86 (95% CI, 1.44; 10.33, (P=0.007)), P-test for heterogeneity, 0.18 (I2=35.9%). No improvement of serum creatinine after IFN compared to immunosuppressive therapy was noted (OR, 0.59 (95% CI, 0.21; 1.65), NS), P-test for heterogeneity, 0.76 (I2=0%). Only three CCTs gave information on the rate of proteinuria decrease over follow-up (OR, 5.08 (95% CI, 0.69; 37.31), NS). A few major side effects were noted after IFN administration.

Conclusions

Our meta-analysis indicates that standard IFN-doses were more effective than immunosuppressive therapy in lowering proteinuria of patients with HCV-related glomerulonephritis. However, no significant improvement in serum creatinine was seen by IFN or steroid therapy across the studies. Also, information on proteinuria recurrence after the completion of antiviral therapy was not sufficient. Prospective, randomized trials based on combined antiviral therapy (pegylated IFN plus ribavirin) with adequate dose and follow-up are required to assess the efficacy and safety of antiviral treatment of HCV-associated glomerulonephritis.

Alexithymic characteristics in pediatric patients with primary headache: a comparison between migraine and tension-type headache

Background

Alexithymia is a personality construct characterized by difficulties in verbal emotional expression and a limited ability to use one’s imagination. Evidence of alexithymic characteristics was found in adults suffering from headache, while little is known about children. The aim of this study was to establish the prevalence of alexithymia in two different subgroups of children and adolescents suffering from primary headache. We also looked for correlation between alexithymia in children and in their mothers.

Methods

This study involved 89 participants: 47 (11 males, 36 females, aged 8 to 17 years) suffering from tension-type headache (TTH), and 42 (18 males, 24 females, aged 8 to 17 years) suffering from migraine (M), based on the International Classification of Headache Disorders (ICHD 2013). A control group of 32 headache-free subjects (26 females and 6 males, aged 8 to17 years) was also considered. Two questionnaires were administered to measure alexithymia: the Alexithymia Questionnaire for Children to young patients and controls, and the Toronto Alexithymia Scale (TAS-20) to the mothers.

Results

Higher rates of alexithymia emerged in the TTH group compared to the M group. In particular, TTH sufferers had difficulty identifying their feelings. The mothers of children with headaches didn’t score higher in alexithymia compared to other mothers. In the M and in the control group, there was a significant correlation between the rates of alexithymia in young people and in their mothers.

Conclusions

To date no other study has investigated alexithymia in subgroups of primary headaches in developmental age. Our results suggest that patients suffering from TTH are more alexithymic than M patients. This pave the way to etiopathogenetic and clinical considerations, calling for a comprehensive and multidisciplinary approach to tackle the problem of headache.

NORMAL NUTRITIONAL COMPONENTS AND EFFECTS ON BONE METABOLISM IN PREVENTION OF OSTEOPOROSIS

Osteoporosis is the most common bone disease, affecting millions of people and causing a high risk of fractures and a loss of quality of life. It is characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. A primary method of prevention, in order to reduce the risk of fractures, is represented by an appropriate lifestyle and a correct diet. There are potentially numerous nutrients and dietary components that can influence bone health, and these range from macronutrients to micronutrients as well as bioactive food ingredients. The purpose of this review is to overview osteoporosis, including its definition, etiology, and incidence, and then provide some information on possible dietary strategies for optimizing bone health and preventing osteoporosis. A correct diet to prevent osteoporosis should contain adequate amounts of calcium, vitamins D and K, protein, and fatty acids. The effects of these elements are briefly discussed, reporting on their correlation with bone benefits.

Lamivudine treatment for hepatitis B in dialysis population : case reports and literature review

It is well known that chronic hepatitis B plays a detrimental role on survival in patients on long-term dialysis and after kidney transplantation. The advent of nucleos(t)ide analogues offers the opportunity to change the natural history of hepatitis B in patients with chronic kidney disease. We report our experience on lamivudine use in two patients with HBV-related liver disease on long-term dialysis. At the beginning, both the patients were HBsAg positive and HBeAg positive with high viral load; after long-term lamivudine therapy, clearance of HBV viremia from serum was observed in both. Raised aminotransferase levels fell into the normal range and one patient experienced clearance of HBsAg by anti-HBV therapy. Tolerance to lamivudine was satisfactory and lamivudine resistance was not detected. Information on antiviral therapy with lamivudine in HBsAg positive patients on regular dialysis is extremely limited; we identified by an extensive review of the literature five studies with a total of 38 unique patients, most of them being renal transplant candidates. Lamivudine proved to be effective as the clearance of HBV viraemia from serum ranged between 56% and 100% ; the clearance of HBeAg from serum was less evident (between 37.5% and 100%). No significant side-effects due to lamivudine were observed and emergence of lamivudine-resistant strains was observed in two (5%) patients. Only a minority of patients experienced HBsAg loss (13%). We conclude that anti-HBV treatment with a nucleoside analogue such as lamivudine gives satisfactory results in some patients on long-term dialysis. Clinical trials are in progress to assess efficacy and safety of last-generation nucleos(t)ide analogues for anti-HBV therapy in dialysis population.

Kinetics of hepatitis B virus load and haemodialysis: a prospective study

The control of the spread of hepatitis B virus (HBV) infection within dialysis units has been an important goal in the management of patients on regular dialysis but infected patients continue to enter the dialysis system. It is evident that HBV viraemia in hepatitis B surface antigen (HBsAg)-positive patients on dialysis is low but it remains unclear whether haemodialysis per se can contribute to viral load reduction in such patients. HBV DNA was determined in 40 HBsAg-positive patients on maintenance haemodialysis immediately before and at the end of a 4-h haemodialysis session. The same measurements were repeated 48 and 72 h later. Twenty (50%) of 40 HBsAg-positive patients had detectable HBV DNA in serum. Detectable HBV DNA in serum was not predicted by demographic, clinical or biochemical parameters. HBV load decreased in the majority of patients after haemodialysis, although the difference was not significant (29 390 +/- 48 820 vs 23 862.8 +/- 4 350 copies/mL, NS). There was a strong relationship between mean HBV DNA levels before dialysis and absolute reduction of HBV DNA during haemodialysis sessions (r = 0.75, P = 0.0001). No difference occurred in the magnitude of change in HBV DNA titre when comparing cellulosic to synthetic membranes. Haemodialysis per se leads to a reduction in HBV load in HBsAg-chronic carriers on maintenance dialysis. This phenomenon could explain the low viral loads in these patients. Prospective studies are in progress to identify the mechanisms responsible for reduction in HBV load during haemodialysis.

The hairy elbows syndrome: clinical and neuroradiological findings

The hairy elbows syndrome (HES) is a rare congenital phenotype characterized by an abnormal increase in long hairs localized on the upper limbs extensor surfaces. This feature is often associated with short stature, facial asymmetry, dysmorphisms, intrauterine growth retardation (IUGR), and mental and speech delay. We report a case with hypertricosis cubiti associated with infantile spasms, behaviour disorders and cerebral hemisphere asymmetry. Although these findings have not been previously described we are uncertain whether they are unusual or underestimated. However, it is likely that these neurological findings are strongly interrelated leading to a more severe phenotype of the syndrome.

[The role of the nephrologist in the management of vascular access for hemodialysis]

The role of the nephrologist in the management of vascular access for hemodialysis has recently been the subject of intense debate on the SIN mailing list. In the present issue, the topic is commented on in view of some literature data. The DOPPS Study has provided information about vascular access practice patterns in different countries. The use of arteriovenous fistula (AVF) is much more frequent in Europe than in the USA (80% vs 24%), where grafts are the most frequent vascular access (58%). In Europe, AVF is most common in Italy (90%), where nephrologists are largely in charge of vascular access surgery. AVF survival has been demonstrated to be longer than graft survival. Vascular access is also associated with patient survival, as the mortality and hospitalization risks are higher in patients with central venous catheters (CVC) and lower in those with AVF. Independent of who is in charge of vascular access surgery, nephrologists play a pivotal role as the main actors of patient care. Nephrological follow-up before dialysis initiation has been independently associated with permanent vascular access and improved patient survival. The Canadian experience, where CVC use is high due to the lag between patient referral and vascular access surgery, has taught that it is mandatory to give vascular access surgery sufficient room and time. In this respect, the nephrologist has an important role to play in the organization of vascular access surgery to fulfill patients' needs in real time.

Gamma glutamyltranspeptidase activity and viral hepatitis in dialysis population

BACKGROUND

Numerous investigations have reported that viral hepatitis is associated with significant hepatocellular damage, as expressed by raised aminotransferases in serum, in dialysis population. However, scarce information exists on the activity of gamma glutamyltranspeptidase (GGTP) in dialysis patients with infection by hepatotropic viruses.

OBJECTIVES

We measured serum GGTP values in a large cohort (n=757) of patients receiving long-term dialysis; healthy controls were also included. The relationship between GGTP values and a series of demographic, clinical, and biochemical parameters was analyzed.

METHODS

Serum GGTP levels were tested by spectrophotometry. A subset (n=333) of dialysis patients was tested by molecular technology (branched-chain DNA (bDNA) assay) to evaluate the relationship between serum GGTP and HCV viremia. A subgroup (n=78) of dialysis patients was analyzed by an ultrasound scan of gallbladder and biliary tract to assess the presence of gallstone disease. Multivariate analyses were made using regression models; serum GGTP values were included as a dependent variable. The usefulness of serum GGTP levels in detecting HBsAg and anti-HCV positivity was evaluated using receiver operating characteristics (ROC) curve analysis.

RESULTS

Univariate analysis showed that serum GGTP levels were significantly higher in HBsAg positive and/or anti-HCV positive patients than in HBsAg negative/anti-HCV negative patients on dialysis; 85.1+/-184.1 versus 25.86+/-23.9 IU/l (P=0.0001). The frequency of raised GGTP levels was 22.2% (41/184) among dialysis patients with chronic viral hepatitis. Multivariate analysis showed a significant and independent association between serum GGTP values and positive HBsAg (P=0.005) and anti-HCV antibody (P=0.0001) status. Mean GGTP values were significantly higher in study patients than controls, 32.32+/-60.02 versus 23.5+/-16.92 IU/L (P=0.01); however, no significant difference with regard to GGTP between study and healthy cohorts persisted after correction for age, gender, race, and viral markers. No relationship between gallstone disease and serum GGTP was found (NS). An independent and significant association (P=0.0291) between raised GGTP levels and detectable HCV RNA in serum was noted among patients tested by biology molecular techniques. ROC technology demonstrated that GGTP was equally useful for detecting HBV (P=0.0004) and HCV (P=0.0005) among dialysis patients.

CONCLUSIONS

We found an independent and significant association between serum GGTP values and HBsAg and/or anti-HCV antibody in dialysis population. Twenty-two percent of dialysis patients with chronic viral hepatitis had elevated GGTP. No difference in GGTP between HBsAg- negative/anti-HCV- negative dialysis patients and healthy individuals was found. Routine testing for serum GGTP levels to assess liver disease induced by hepatotropic viruses or other agents in dialysis population is suggested.

Reduction in urea distribution volume over time in clinically stable dialysis patients

We have previously shown that, assuming urea distribution volume (V) remains constant for 1 month, ionic dialysance (ID) allows the dialysis dose to be calculated without the need for blood sampling. The aim of this multicenter study was to verify whether the assumption of a constant V can be extended to 1 year. In clinically stable patients receiving thrice-weekly hemodialysis at 13 dialysis centers, V and Kt/V were assessed during three dialysis sessions at baseline and 1 year later using ID as dialyzer urea clearance and the single-pool urea kinetic model. Baseline albumin, hemoglobin, and C reactive protein were prespecified covariates for predicting the change in V over time. Of the 52 enrolled patients, 40 (25 males; age 63.0+/-13.5 years) completed the study. Baseline end-dialysis body weight (62.4+/-13.7 kg) showed a non-significant 1% reduction during follow-up (-0.6+/-2.8 kg; P=0.175), whereas V significantly decreased from 29.0+/-6.8 to 27.4+/-6.0 l (-1.6+/-3.0 l or 4.5%; P=0.002). The reduction in V was greater when baseline albumin was lower (P=0.001) and baseline V was higher (P=0.005). The single-pool K(t)/V calculated using baseline V underestimated the actual value by 0.07+/-0.16 (P=0.008). The slight underestimate of Kt/V during follow-up suggests that annual V evaluations may be sufficient for dialysis dose quantification as the only risk is underestimating the actually delivered dialysis dose. However, the relationship between baseline albumin and the reduction in V over time may have nutritional value, and suggests more frequent V evaluations.

[From the Mailing List SIN: Epidemic of infections caused by 'aquatic' bacteria in patients undergoing hemodialysis via central venous catheters]

Bacteremia due to central venous catheter (CVC) infection is the most frequent complication of CVC use as vascular access for hemodialysis (HD). We report a case of an epidemic of CVC infections caused by 3 strains of unusual bacteria: Ralstonia pickettii (Rp), Leifsonia xyli/Leifsonia aquatica (Lxa), Tsuckamurella strandjordae (Ts). From 20/8/01 to 30/9/01, 23 of 35 patients dialyzed via CVCs experienced intra-HD pyrogenic reactions. Their hemocultures were positive for: Rp (14 pts), Lxa (3 pts), Rp+Lxa (5 pts) and Rp+Ts (1 pt). The hemocultures of 12/35 asymptomatic pts were positive for: Rp 2 pts, Lxa 2 pts, Rp+Lxa 2 pts, Ts 1 pt, Rp+Ts 1 pt. The epidemiological and microbiological analyses of environmental samples failed to identify the source of the epidemic. Actions taken were: a) replacement of the batches of disposable materials; b) removal of CVCs in cases where possible to prepare a different access; c) treatment of the infections with intra-CVC antibiotic lock therapy. No relapses were recorded until April 2002, when 8 pts had again pyrogenic reactions due to Rp. After quick substitution of the CVC and repetitions of the action a), no relapses of pyrogenic reactions were observed.

CONCLUSIONS

1) given the characteristics of Rp, Lxa and Ts, saprophytes of moist environments, the most plausible source of the epidemic was a low-charge contaminated solution that was not identified due to low sensitivity of environmental sample culturing methods; 2) antibiotic lock therapy is a viable option for the conservative treatment of CVC infections.

Occult hepatitis B virus infection in dialysis patients: a multicentre survey

BACKGROUND

The epidemiology and clinical significance of occult hepatitis B virus infection (serum hepatitis B surface antigen-negative patients with detectable hepatitis B virus viraemia in serum) remains controversial with only limited information about its prevalence in patients on long-term dialysis.

AIM

To address the epidemiology of occult HBV infection in a large cohort of dialysis patients.

METHODS

We screened a large cohort (n = 585) of Italian chronic dialysis patients; from this population, a group of hepatitis B virus surface antigen seronegative patients (n = 213) was tested by Amplicor hepatitis B virus Monitor Test to detect hepatitis B virus viraemia (hepatitis B virus-DNA) in serum.

RESULTS

Occult hepatitis B virus infection was absent (zero of 213 = 0%). Persistent hepatitis B virus surface antigen carriage was less frequent than anti-hepatitis B virus core antibody (anti-hepatitis B core antigen) seropositive status in this study group [1.88% (11 of 585) vs. 36% (216 of 585), P = 0.0001]. No dialysis patients seropositive for anti-hepatitis B core antibody in serum (zero of 123 = 0%) had detectable hepatitis B virus-DNA by polymerase chain reaction technology. No significant association between abnormal biochemical liver tests and serum anti-hepatitis B core antibody was noted in our population. Nominal logistic regression analysis demonstrated an independent and significant relationship between anti-HCV antibody and anti-hepatitis B virus core antibody in serum (Wald chi-square 16.06, P = 0.0001). The rate of seropositive patients for anti-hepatitis B virus core antibody was higher among study patients than controls with normal renal function [36.9% (216 of 585) vs. 21.4% (59 of 275), P = 0.0001]; this difference partially persisted after correction for demographic parameters, and viral markers.

CONCLUSION

In conclusion, occult hepatitis B virus was absent in our study group. Anti-hepatitis B core antibody was significantly related to presence of anti-HCV antibody supporting shared modes of transmission. Clinical studies based on molecular biology techniques provided with higher sensitivity are planned.

Occult hepatitis B virus infection in dialysis patients: a multicentre survey

BACKGROUND

The epidemiology and clinical significance of occult hepatitis B virus infection (serum hepatitis B surface antigen-negative patients with detectable hepatitis B virus viraemia in serum) remains controversial with only limited information about its prevalence in patients on long-term dialysis.

AIM

To address the epidemiology of occult HBV infection in a large cohort of dialysis patients.

METHODS

We screened a large cohort (n = 585) of Italian chronic dialysis patients; from this population, a group of hepatitis B virus surface antigen seronegative patients (n = 213) was tested by Amplicor hepatitis B virus Monitor Test to detect hepatitis B virus viraemia (hepatitis B virus-DNA) in serum.

RESULTS

Occult hepatitis B virus infection was absent (zero of 213 = 0%). Persistent hepatitis B virus surface antigen carriage was less frequent than anti-hepatitis B virus core antibody (anti-hepatitis B core antigen) seropositive status in this study group [1.88% (11 of 585) vs. 36% (216 of 585), P = 0.0001]. No dialysis patients seropositive for anti-hepatitis B core antibody in serum (zero of 123 = 0%) had detectable hepatitis B virus-DNA by polymerase chain reaction technology. No significant association between abnormal biochemical liver tests and serum anti-hepatitis B core antibody was noted in our population. Nominal logistic regression analysis demonstrated an independent and significant relationship between anti-HCV antibody and anti-hepatitis B virus core antibody in serum (Wald chi-square 16.06, P = 0.0001). The rate of seropositive patients for anti-hepatitis B virus core antibody was higher among study patients than controls with normal renal function [36.9% (216 of 585) vs. 21.4% (59 of 275), P = 0.0001]; this difference partially persisted after correction for demographic parameters, and viral markers.

CONCLUSION

In conclusion, occult hepatitis B virus was absent in our study group. Anti-hepatitis B core antibody was significantly related to presence of anti-HCV antibody supporting shared modes of transmission. Clinical studies based on molecular biology techniques provided with higher sensitivity are planned.

Review article: hepatitis C virus infection and type-2 diabetes mellitus in renal diseases and transplantation

A link between hepatitis C virus infection and development of diabetes mellitus has been suggested by many investigators; however, this remains controversial. The mechanisms underlying the association between hepatitis C virus and diabetes mellitus are unclear but a great majority of clinical surveys have found a significant and independent relationship between hepatitis C virus and diabetes mellitus after renal transplantation and orthotopic liver transplantation. We have systematically reviewed the scientific literature to explore the association between hepatitis C virus and diabetes mellitus in end-stage renal disease; in addition, data on patients undergoing orthotopic liver transplantation were also analysed. The unadjusted odds ratio for developing post-transplant diabetes mellitus in hepatitis C virus-infected renal transplant recipients ranged between 1.58 and 16.5 across the published studies. The rate of anti-hepatitis C virus antibody in serum was higher among dialysis patients having diabetes mellitus (odds ratio 9.9; 95% confidence interval 2.663-32.924). Patients with type-2 diabetes-related glomerulonephritis had the highest anti-hepatitis C virus prevalence [19.5% (24/123) vs. 3.2% (73/2247); P < 0.001] in a large cohort of Japanese patients who underwent renal biopsy. The link between hepatitis C virus and diabetes mellitus may explain, in part, the detrimental role of hepatitis C virus on patient and graft survival after orthotopic liver transplantation and/or renal transplantation. Preliminary evidence suggests that anti-viral therapies prior to renal transplantation and novel immunosuppressive regimens may lower the occurrence of diabetes mellitus in hepatitis C virus-infected patients after renal transplantation. Clinical trials are under way to assess if the hepatitis C virus-linked predisposition to new onset diabetes mellitus after renal transplantation may be reduced by newer immunosuppressive medications.

Double subepicardial aneurysm after myocardial infarction

The echocardiogram of 68-year old man, admitted with an acute myocardial re-infarction revealed the presence, in the middle-apical region of the lateral wall, of two little and contiguous subepicardial aneurysms.

Influence of hepatitis B virus virema upon serum aminotransferase activity in dialysis population

BACKGROUND

The control of the spread of hepatitis B virus (HBV) infection within dialysis units has been one of the major advances in the management of patients with end-stage renal disease (ESRD). However, clinical and biochemical expression of HBV in dialysis patients have not been adequately addressed. Elevated values of serum aminotransferase activity are a sensitive measure of hepatocellular injury, but the role of HBV infection in the development of liver disease among dialysis patients has not been adequately analysed. Also, the clinical impact related to the virological characteristics of HBV in dialysis has not been evaluated.

METHODS

Demographic, biochemical and virological data from 727 patients undergoing chronic dialysis in seven dialysis units in northern Italy were collected in order to assess the biochemical consequences related to the presence of HBV infection in this population. We have measured by RT-PCR technology the titers of HBV viremia in HBsAg positive patients receiving dialysis.

RESULTS

Univariate analysis showed that AST and ALT values were significantly higher in HBsAg positive/HBV DNA positive than HBsAg negative patients on dialysis; AST, 22.86+/-31.34 vs. 14.19+/-9.7 IU/L (P=0.00001); and ALT, 25.07+/-41.59 vs. 13.9+/-41.59 IU/L (P=0.00001). In the subgroup of HBsAg positive patients, the frequency of detectable HBeAg in serum was 14.9% (7/47). The median value of HBV DNA in patients with detectable HBV DNA in serum was 2.160 x 10(3) copies/mL (range, 2.5 x 10(2)-4 x 10(6) copies/mL). HBsAg positive/HCV positive patients had higher aminotransferase activity than other subgroups (P=0.0001). Multivariate analysis showed a significant and independent association between detectable HBsAg/HBV DNA in serum and AST (P=0.00001) and ALT (P=0.0001) activity AST and ALT levels were lower in dialysis than healthy individuals--this finding persisted in age- and gender-matched comparisons.

CONCLUSIONS

The HBV viral load in HBsAg positive patients receiving maintenance dialysis is not high. HBsAg positivity with detectable HBV DNA in serum is a strong and independent predictor of raised aminotransferase activity among dialysis patients. HBsAg positive patients had greater aminotransferase activity than HBsAg negative individuals even if both the groups had mean aminotransferase levels within the normal range considered for healthy population. Clinical trials aimed at identifying the best cut-off value to enhance the diagnostic yield of AST/ALT for detecting HBV in dialysis population are under way.

[To delay may be wise]

We report a case of acute renal failure, quickly evolved, in which the coexistence of parenchimal nephropaty and renal mass, have induced not a common diagnostic and therapeutic approach, finalized to optimize the interventional nephrology procedures, with the use of various imaging procedures. It is followed a multidisciplinar therapeutic approach, with the employment of dialysis, steroid therapy and surgical treatment.

[Hepatopathy and hepatitis B virus infection in dialysis patients: cross-sectional study]

BACKGROUND

Control of spread of HBV infection in dialysis units in developed countries has been one of the major advances in managing end-stage renal disease (ESRD). Patients with chronic HBV, however, continue to enter the population pool of dialysis patients and transplant candidates. The clinical significance related to the presence of HBsAg in serum of dialysis patients has not been completely understood.

AIM AND METHODS

We collected demographic, biochemical and virological data from a large (n=464) population of patients on maintenance dialysis. This was done to assess the influence of virological and host factors on hepatocellular damage, as shown by serum aminotransferase activity.

RESULTS

The frequency of HBsAg positivity in our dialysis population was 8.2 % (38/464); the rate of HBsAg positive patients showing HBe antigen was 20.6% (7/34). Twenty-two (84.6%) of 26 HBsAg positive patients showed detectable HBV DNA in serum by Amplicor HBV MonitorTM Test. HBsAg positive patients had serum aminotransferase activity significantly higher than HBsAg negative individuals; GOT (AST) 25.1+/-29.9 vs. 16+/-21.5 UI/L (p=0.001), and GPT (ALT) 31.3+/-52.5 vs. 17.7+/-21.9 UIL (p=0.034). In the subset of HBsAg positive dialysis patients, those in the replicative phase HBeAg positive) had aminotransferase activity higher than HBeAg negative individuals, AST, 42.3+/-43.6 vs. 22.4+/-27.3 UI/L (p=0.097) and ALT, 49.41+/-54.7 vs. 29.17+/-55.76 UI/L (NS) respectively. We did a multivariate analysis by standard least square model on the entire patient group and we found independent and significant association between detectable HBsAg in serum and AST (p=0.0089)and ALT (p=0.0159) values. There was an independent and significant relationship between age and ALT (p=0.01).

CONCLUSIONS

In our study group, HBsAg positive patients on dialysis had serum aminotransferase activity significantly higher than that measured in HBsAg negative individuals. However, mean transaminase levels in HBsAg positive patients on dialysis were below the upper limit of normal for the reference range of healthy controls. HBsAg positive dialysis patients with active viral replication showed the greatest liver damage. Studies are in progress to understand further HBV-related liver disease in dialysis population.

Effect of on-line conductivity plasma ultrafiltrate kinetic modeling on cardiovascular stability of hemodialysis patients

The aim of this multicenter, prospective, randomized cross-over study was to clarify whether on-line conductivity ultrafiltrate kinetic modeling (treatment B), as a substitute for sodium kinetic modeling, is capable of reducing intradialytic cardiovascular instability in comparison with standard treatment (treatment A), by reducing the sodium balance variability. Both treatments were performed by means of a modified hemodiafiltration technique. Treatment A was performed using fixed dialysate conductivity; treatment B made use of the dialysate conductivity derived from a conductivity kinetic model, in order to obtain an end-dialysis ultrafiltrate conductivity at each dialysis session that was equal to the mean value determined in the same patient during the four-week run-in period. Thus, during treatment B, the expected end-dialysis ultrafiltrate conductivity value of each patient should have been constant. The study was carried out according to a multicenter cross-over design of 16 weeks with two treatments (A or B), two sequences (1 = ABB and 2 = BAA), a run-in period of four weeks (period 1, treatment A), and three consecutive experimental periods of four weeks each. Analysis of variance for a cross-over design was used for the statistical analysis. Forty-nine hemodialysis patients prone to intradialytic hypotension (> 25% of sessions) were enrolled from 16 participating centers, and randomly assigned to either sequence 1 (26 patients) or sequence 2 (23 patients). Six patients dropped out and four were protocol violators, which left 39 patients selected for statistical analysis. There was no difference in the average dialysate conductivity, predialysis and end-dialysis plasma water ultrafiltrate conductivity or body weight between treatment A and treatment B. Thus, the observed mean sodium balance was not different and, as expected, only the intra-patient variability of end-dialysis ultrafiltrate conductivity (index of sodium balance variability) was reduced (21%). During treatment A, systolic blood pressure decreased by 23 mm Hg (95% confidence intervals 21 to 24 mm Hg) at the end of dialysis with respect to the pre-dialysis values. Treatment B reduced this intradialytic decrease (P = 0.001) with a maximum effect at the third hour of dialysis (4.4 mm Hg, 95% confidence intervals 1.9 to 6.9 mm Hg, 23% less than during treatment A, P 0.0005) without any period or carry-over effect (P = 0.53 and 0.08, respectively). There was no treatment effect on intradialytic diastolic blood pressure (P = 0.291). In conclusion, intradialytic cardiovascular stability was significantly improved by matching the interdialytic sodium load with intradialytic sodium removal using on-line conductivity ultrafiltrate kinetic modeling as an alternative to sodium kinetic modeling. Although highly significant, this effect was clinically not very large. By applying this conductivity kinetic model to patients with a more variable sodium intake from one session to another, a greater benefit can be expected.

Molecular epidemiology of hepatitis C virus infection in dialysis patients

There are very few data on the molecular biology of hepatitis C virus (HCV) infection in dialysis patients. 101 patients undergoing dialysis treatment in 4 units in the Lombardy, northern Italy, were analyzed by RT-PCR for HCV viremia, by line probe assay technology for HCV genotyping and by a serological analysis for detecting type-specific antibodies. 61 of 101 (60%) patients showed detectable HCV RNA in serum; HCV genotype 2a was dominant (30/53 = 57%), followed by HCV genotype 1b (20/53 = 37%). There was no relationship between HCV genotyping and the clinical or demographic features of the patients. The antibody response toward the c33-c, c100-3, and 5-1-1 antigens was more frequent in HCV genotype 1b compared with genotype 2a (p = 0.046, p = 0.001 and p = 0.0001, respectively). The antibody levels to NS-3 and NS-4 HCV proteins were significantly higher in patients with-HCV genotype 1b in comparison with HCV 2a-infected individuals (p = 0.0001). There was a high level (82%) of agreement between HCV genotyping by RT-PCR and the assessment of type-specific antibodies by serological analysis; further, it was possible to detect type-specific antibodies in 6 of 22 (27%) patients in whom PCR amplification was unsuccessful. In conclusion, HCV subtype 2a was dominant in our population of HCV-infected dialysis patients, dialysis patients infected by different genotypes showed similar demographic and clinical characteristics, the antibody response toward the NS-3- and NS-4-related antigen of HCV was genotype dependent. There was a high level of agreement between HCV genotyping by RT-PCR and the detection of type-specific antibodies by serological analysis. As significant biological differences may exist among HCV strains, the assessment of HCV types may be very useful in the routine clinical activity of nephrologists in dialysis units.

Influence of hepatitis C virus (HCV) viraemia upon serum aminotransferase activity in chronic dialysis patients

BACKGROUND

There are many reports concerning HCV in dialysis patients and most of them conclude that the clinical and biochemical features of hepatitis C are often silent in chronic dialysis patients. Elevated levels of serum alanine aminotransferase activity are a sensitive measure of hepatocellular injury, but so far the relationship between anti-HCV and ALT among chronic dialysis patients has been considered imperfect. To our knowledge, however, such an issue has not been adequately addressed.

METHODS

Demographic, biochemical, and virological data from 506 patients undergoing chronic dialysis treatment in four dialysis units in Lombardy, northern Italy were collected in order to assess the influence of virological and host factors on serum aminotransferase values.

RESULTS

Analysis of covariance showed that positivity for anti-HCV antibody was significantly associated with raised serum AST (P = 0.0001) and ALT (P = 0.0001) levels in the dialysis patients of the whole study group. Logistic regression analysis performed in the subset of patients tested for HCV viraemia and genotype showed that detectable HCV RNA in serum is a strong predictor of raised AST (P = 0.0001) and ALT (P = 0.000001) values. Gender showed an independent weak influence on AST levels (P = 0.055), serum levels of ferritin were significantly (P = 0.042) associated with AST values, the coexistence of HBsAg infection and positivity for anti-HCV antibody was independently associated with raised ALT levels (P = 0.016). The other factors (including positivity for anti-HCV) showed no independent effect on serum aminotransferase levels when they were matched with HCV viraemia in our multivariate analysis. HCV RNA positive patients showed serum AST (P < 0.008) and ALT levels (P < 0.0001) higher than HCV RNA negative patients. There was no relationship between HCV genotypes and liver enzymes.

CONCLUSIONS

Our data show that detectable HCV RNA in serum is a strong independent predictor of raised aminotransferase values in chronic dialysis patients; the relationship between serum aminotransferase values and anti-HCV antibody was exclusively related to the association between raised aminotransferase values and HCV viraemia; HCV RNA positive patients show higher hepatic enzyme levels than dialysis patients with no detectable HCV RNA; no association between HCV genotype and serum aminotransferase activity was apparent.

[The allorhythmic distribution of ectopic ventricular beats. Observations on the electrogenesis and dynamics of concealed ventricular extrasystole]

BACKGROUND

A regular distribution of ventricular ectopic beats is thought to be a relatively uncommon phenomenon, known as "concealed extrasystole". Several experimental studies suggest that the phenomenon originates from a "protected" ventricular focus. The aim of the present study was to evaluate the 24-hour ECG monitoring incidence of ventricular concealed extrasystole in patients with highly frequent ventricular ectopic beats, looking for signs useful in postulating the electrogenesis of the arrhythmia.

METHODS

The 24-hour ECGs of 10 patients (pts) with highly frequent ventricular extrasystoles were analysed, searching for significant sequences in the distribution of ectopic beats (i.e., ectopic beats separated by a number of interectopic sinus beats fulfilling one of the formulas of concealed extrasystole).

RESULTS

Five cases (50%) showed an allorhythmic distribution resulting in a prevalent pattern of concealed bigeminy (2n-1) in 3 cases, and concealed trigeminy (3n-1) in 2 cases. The phenomenon, however, showed a dynamic behaviour, alternating the distributions from patterns of concealed bigeminy to concealed trigeminy or less common patterns, and vice versa. The evidence of the pure ectopic cycle and mathematically related interectopic intervals in 2 cases, the variability of coupling intervals, and the presence of fusion beats in the remaining 3 cases, strongly suggests a parasystolic origin of the phenomenon.

CONCLUSIONS

The results suggest the following: Concealed extrasystole is a relatively common phenomenon, at least in patients with highly frequent ventricular extrasystoles; the phenomenon, however, is somewhat underestimated due to prevalent quantitative, instead of qualitative, Holter monitoring analyses. Among patients with allorhythmically distributed ventricular extrasystoles, none showed only one pattern of distribution. In fact, each single patient showed two or more patterns throughout the 24-hour recordings. Changes from one pattern to another is governed by several factors, such as sinus heart rate and/or the influence of electrotonic "modulation" upon the ectopic focus. Ventricular extrasystoles with regular allorhythmic distribution show a significantly higher variability of coupling intervals than the others (p = 0.005).

Incontinentia pigmenti: clinical and neuroradiologic features

Developmental brain malformations and destructive processes of unknown etiology were described in incontinentia pigmenti (IP). Two patients, a male and a female, with characteristic skin lesions and central nervous system (CNS) involvement are reported. Neuroradiological examinations revealed hypoplasia of corpus callosum, neuronal heterotopias, and periventricular white matter damage. No specific infectious, inflammatory, or metabolic abnormalities were identified. These neuroradiographic findings may suggest that an ischemic pathogenetic mechanism occurred prenatally. We speculate that the brain damage in IP may occur during CNS development and in successive stages. Magnetic resonance imaging appears more useful to detect white matter lesions and brain malformations in patients with IP.

Modification of the characteristics of regurgitant jets when impinging upon a surface: an in-vitro investigation using Doppler colour flow mapping

Free jets were compared in vitro by colour Doppler flow mapping with jets striking a flat and a hemispherical surface, located 3 and 6 cm from a circular orifice (5 mm in diameter). The angles of the impinging jets were 45 degrees and 90 degrees. Flow rates from 6-52 ml.s-1 were tested (pulsatile jets, 0.5 s duration). Free jet areas (21.7 +/- 9.6 cm2) were larger (P less than 0.01) than that of impinging jets (14.3 +/- 5.6 cm2). The distance of the target was a significant factor for reducing areas of striking jets (P less than 0.001). The angle of incidence of the striking jet and the shape of the target surface were not independent factors, but they were important when interacting with flow rate (P less than 0.001). The percentage of total jet area of impinging jets occupied by swirling flow was larger for targets located at 3 cm (P less than 0.01), for a 90 degrees angle of incidence (P less than 0.01), for a flat target surface (P less than 0.05). We conclude that jets visualized in vitro by colour Doppler flow mapping are significantly modified when impinging a surface, with the interplay of several factors. This can be of importance in clinical settings.

Prevalence of antibodies against hepatitis C virus in a dialysis unit

Anti-HCV was tested in 77 uremic patients, 48 on hemodialysis (HD), 29 on CAPD, by immunoenzymatic 1st and 2nd generation assays (ELISA I, II) and 4-antigen (4-RIBA) immublotting. The investigation was extended to the staff (n = 29) and to HCV-positive patients' families (n = 30). The prevalence using 2nd generation tests was double (21%) that in 1st generation tests (11%). A greater incidence in the HD than in the CAPD group (23 vs. 17%) and a highly significative correlation to dialytic age were observed. No one among the sanitary personnel and only 2 family members were found HCV positive, suggesting a low infectivity via the parenteral inevident route. Extracorporeal circulation and particularly the exposure time to the treatment seem to be the main risk factors.

Hemimegalencephaly and neurofibromatosis

Hemimegalencephaly, which previously has been associated with a poor clinical course characterized by intractable seizures and severe encephalopathy, was found without these conditions in two children with neurofibromatosis. These children showed relatively similar and favourable prognostic features: no presence of seizures before one month, seizures controlled or absent, no focal neurological signs and peculiar EEG findings. In our opinion the absence of heterotopias and hamartomas can be related with less severe outcome.

Relation between three-dimensional geometry of the inflow tract to the orifice and the area, shape, and velocity of regurgitant color Doppler jets: an in vitro study

The relation between three-dimensional geometry of the inflow tract to the orifice and the area, shape, and velocity of regurgitant jets was studied in a pulsatile in vitro color Doppler flow model. A 2.5 MHz transducer connected to a diagnostic ultrasound machine was placed in a water tank facing pulsatile jets (duration, 0.5 second) obtained by a calibrated injector. Flow rate from 6 to 52 ml/sec were tested through a 5 mm diameter circular orifice. Four different three-dimensional inflow tract geometries were compared: (A) sharp-edged, (B) Venturi (funnel), (C) converging conical, and (D) diverging conical. Mean velocities of jets were measured by continuous-wave Doppler echocardiography. Driving pressures were also measured by means of a fluid-filled catheter. Two observers independently digitized contours of maximal color jet areas by computer system from two separate sets of experiments. Results are given as the mean values of the four measurements for each parameter. Jet areas were correlated to flow rate, with no difference from A through D. The shape (eccentricity) of jets was different between A and B (p less than 0.05), between B and D (p less than 0.01), and between C and D (p less than 0.01). The shape of jets was correlated with flow rate, continuous-wave velocity, and pressure gradient in B, C, and D but not in A. Measured pressure gradients and estimated gradients by continuous-wave Doppler echocardiography were similarly correlated from A through D.(ABSTRACT TRUNCATED AT 250 WORDS)

[Color Doppler identification of early diastolic turbulence in the left atrium in patients with mitral valve insufficiency: persistence of regurgitation or inertia phenomenon?]

Color Doppler flow mapping represents the most recent non invasive diagnostic tool for the visualization of intracardiac blood flow. By using the color Doppler flow mapping technique, two independent observers identified the persistence of turbulence in early diastole inside the left atrium in a selected group of 8 patients (3 F and 5 M) with mitral insufficiency. All the patients had moderate or severe mitral insufficiency, due to dilated cardiomyopathy and/or ischemic cardiomyopathy and/or valvular disease. The persistence of early diastolic turbulence inside the left atrium was documented and confirmed by using 30 degrees color sector images, which show the highest possible frame rate. The frame by frame analysis facilitated the identification of two simultaneous flow velocities during early diastole, after the mitral valve was open. The first flow was anterograde and was coded as a red signal; it flowed from the mitral valve into the left ventricle and represented early diastolic left ventricular filling. The second flow was retrograde, and was coded as a blue mosaic signal, due to turbulent aliased jet, extending from the mitral valve into the left atrium, away from the transducer. The interpretation of these two dimensional color Doppler findings is uncertain. We believe, however, that these turbulent velocity signals which persist in early diastole and flow from the mitral valve into the left atrium are probably caused by inertial blood flow due to the impact of regurgitant mitral jets during the previous systole.

[Usefulness of the Doppler color technic in the diagnosis of thrombosis in a mitral valve mechanical prosthesis and in the monitoring of the results of thrombolytic therapy]

We report the usefulness of Doppler color echocardiography in diagnosis and follow-up in a case of thrombosis of a prosthetic mitral valve. The patient received thrombolytic therapy for this disorder and a favorable clinical outcome was observed. Integrated echocardiographic techniques (M-Mode, cross-sectional, continuous-wave, pulsed-Doppler and color Doppler) could increase the amount of diagnostic information in these situations.