Dark matter results from 100 live days of XENON100 data

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.

Evidence of exposure to spotted fever group rickettsiae among Arizona dogs outside a previously documented outbreak area

Since 2003, two communities in eastern Arizona have experienced a sustained outbreak of Rocky Mountain spotted fever (RMSF), caused by Rickettsia rickettsii, associated with transmission by Rhipicephalus sanguineus, the brown dog tick; 70 human cases, including eight deaths, were reported from these communities during 2003 through 2008. In both of the affected communities, antibodies to spotted fever group rickettsiae (SFGR) were present in dogs before the notice of the first human cases, suggesting that dogs may serve as useful sentinels for human risk of RMSF in this region. During 2005 and 2006, an exploratory serosurvey was conducted among stray and relinquished dogs presenting to animal control facilities in eastern Arizona located outside the area where human cases had been reported. Antibodies to SFGR were detected in 5.7% (14 of 247) dogs assessed outside the RMSF outbreak area. Animal shelters located in counties that either included or shared large borders with the outbreak area were significantly more likely to have seropositive dogs than facilities in more geographically separated counties (P = 0.01). In addition, stray dogs were significantly more likely to be antibody-positive than relinquished animals (P = 0.01), suggesting that control of stray dog populations should be considered as a means of limiting SFGR transmission in this region. The findings from this study may be extrapolated to suggest that the current risk for human RMSF infection may extend beyond the noted outbreak area. Heightened surveillance for human disease is needed in the region.

Natural history of small duct primary sclerosing cholangitis: a case series with review of the literature

BACKGROUND AND AIMS

Information about the natural history of small duct primary sclerosing cholangitis (SDPSC) remains scant despite literature suggesting that it constitutes 6-16% of all cases of primary sclerosing cholangitis (PSC). We combined clinical data on SDPSC cases from two tertiary care institutions with liver transplantation programs with the aim of studying the natural history of SDPSC.

METHODS

Medical records of 25 individuals with SDPSC were reviewed. Diagnosis of SDPSC was based on liver biopsy findings consistent with PSC, a normal cholangiogram, and elimination of known causes of secondary sclerosing cholangitis. Demographic information, symptoms, past medical history, laboratory values, and histologic data were evaluated. Our primary outcome measure was liver transplantation or death. Secondary outcome measures included evidence of end-stage liver disease, development of cholangiocarcinoma, and/or the development of classic PSC on a repeat cholangiogram.

RESULTS

Data on 25 individuals (13 males, 12 females; mean age 40 ± 15 years) diagnosed with SDPSC were analyzed. Upon presentation, 11 patients had symptoms including abdominal pain, fatigue, and pruritus. Inflammatory bowel disease was present in 14 patients (56%) at diagnosis. On initial liver biopsy, 60% had early-stage disease (I or II) and none had cirrhosis. On follow-up (1-168 months, median 17 months), malignancy or progression to classic large duct PSC was not noted. Two (8%) patients had evidence of varices and one of the two also developed ascites; one of these patients underwent liver transplantation and the other one died due to sepsis.

CONCLUSIONS

SDPSC, a mild disease at presentation typically runs a benign course and likely is not an early stage of classic PSC. Further studies with a control group of classic PSC and longer follow-up are needed to study the natural history of SDPSC.

Pilot study: fenofibrate for patients with primary biliary cirrhosis and an incomplete response to ursodeoxycholic acid

BACKGROUND

Newer therapies are needed for patients with primary biliary cirrhosis and incomplete response to ursodeoxycholic acid (UDCA). Fenofibrate is a fibric acid postulated to regulate immune response and cell proliferation.

AIM

To evaluate the efficacy and safety of fenofibrate in patients with primary biliary cirrhosis and incomplete response to UDCA.

METHODS

We undertook a pilot study involving 20 patients with primary biliary cirrhosis and serum alkaline phosphatase (ALP) ≥ 2× ULN. Nonparametric statistical tests and Spearman correlation test were used as appropriate.

RESULTS

Twenty patients received fenofibrate (160 mg/day) in addition to UDCA for 48 weeks. Median serum ALP decreased significantly at 48 weeks compared with baseline values [351 (214-779) U/L at baseline vs. 177 (60-384) U/L at 48 weeks, P < 0.05]. A rebound in ALP occurred upon drug discontinuation. Serum aspartate aminotransferase and Immunoglobulin M also decreased significantly, while bilirubin and albumin remained unchanged. Median IL-1 decreased from 28.9 (2.7-10 000) to 11.3 (2.5-277.7) pg/mL (P = 0.049), and median IL-6 from 4.6 (3.2-5205) to 3.5 (3.2-73.4) pg/mL (P = 0.027). Heartburn was the most frequent adverse event, leading to discontinuation of two study subjects.

CONCLUSIONS

Combination therapy of fenofibrate and UDCA induced significant biochemical improvement in patients with primary biliary cirrhosis and incomplete response to UDCA. Further studies are warranted.

Late and ultra late onset Streptococcus B meningitis: clinical and bacteriological data over 6 years in France

BACKGROUND

Group B Streptococcus (GBS) is one of the leading causes of sepsis and meningitis in newborn. The objective of this study was to describe the characteristics of GBS meningitis in children aged between 7 and 89 days (late onset disease - LOD group) and to compare them with children aged more than 3 months (ultra late onset disease - ULOD group).

METHODS

Clinical and biological data were gathered by ACTIV/GPIP (a nationwide active surveillance network). The study population included 242 children hospitalized between 2001 and 2006 for GBS meningitis (220 in the LOD group and 22 in the ULOD group).

RESULTS

Univariate analysis revealed that gestational age (GA) was significantly lower in the ULOD group as compared with the LOD group (respectively 35.6 weeks vs. 37.9 weeks, p = 0.002). Prevalence of early preterm birth (before the 32nd week GA) was significantly higher in the ULOD group than in the LOD group (32% vs. 7%, p = 0.002). No significant difference was found between the two groups for biological characteristics of lumbar puncture, GBS serotypes, complications and survival rate.

CONCLUSION

These data suggest that LOD and ULOD would be the same clinical and bacteriological entity, except for prematurity, which seems significantly associated with ULOD.

[Listeria monocytogenes meningitis in children in France]

Listeriosis is a serious invasive disease which affects mainly pregnant women, newborns and immunocompromised adults.

OBJECTIVE

To analyze specifically the epidemiological and clinical data of the meningitis due to Listeria monocytogenes (Lm), from the French Network of Surveillance of Bacterial Meningitis in childhood.

PATIENTS AND METHODS

Patients were aged 0 to 18 years. The diagnosis was based on a combination of a feverish meningeal syndrome and a positive culture of cerebrospinal fluid (CSF) and/or a positive PCR in the CSF and/or positive blood culture associated with a pleiocytose.

RESULTS

Among 2539 cases of bacterial meningitis recorded in 6 years (2001 to 2006), 18 cases were due to Lm (0.7 %) (sex ratio M / F : 0.8). The average of age was 2.5 years (median : 0.5 ; ext : 0-15.1). The serotype of Lm was 4B in half of the cases. Most cases have occured in summer and autumn. Two patients presented an acquired or congenital immunodeficiency. Fifty-six percent (n=10) were younger than 1 year, among them, 7 were newborns. The CSF direct microbiologic investigation was suggestive of Lm (Gram positive bacilli) only in two cases, but the culture of CSF was positive for 16 patients and the blood culture was positive for 2 other patients. Three of 18 patients died between 7 and 13 days after admittance : a premature baby of 25 weeks'gestational age, two full-term newborns of 2 days and 1.5 months old. The mortality rate was 16.7 % before the age of 1 year (no death after this age).

CONCLUSION

Meningitis due to Lm remains a rare disease, including in neonatal period. The recent increase of cases in adults requires to maintain vigilance in children especially since direct examination of CSF can rarely allow the diagnosis.

[Characteristics of meningococcal meningitis in children in France]

BACKGROUND

In France, meningococcal meningitis account for 50% of bacterial meningitis in children. The GPIP/ACTIV (Groupe de Pathologie Infectieuse Pédiatrique and Association Clinique et Thérapeutique Infantile du Val de Marne) set up an active surveillance network to analyze the epidemiological, clinical and biological features of meningococcal meningitis.

METHODS

From 2001 to 2007, 252 French paediatric wards working with 166 microbiology laboratories enrolled all children (0-18 years old) with bacterial meningitis. Risk factors, signs and symptoms, vaccination status, cerebrospinal fluid analysis, treatments and case fatality rate were recorded.

RESULTS

During the period of the study, 1344 meningococcal meningitis were reported among 2951 (45.5%) bacterial meningitis. Mean age was 4.4 years (+/-4.7, median 2.5) and 2/3 cases occurred in children under 5 years (68.5%). Serogroup B (59.1%) was preponderant following by serogroup C (28.9%). 25% of children had received an antibiotic treatment 24hours before lumbar puncture. A shock was reported in 31.3% of cases. Cerebrospinal fluid culture was positive in 73% of cases. All N. meningitidis isolates were susceptible to cefotaxime and ceftriaxone while 41.6% and 25.7% showed reduced susceptibility to penicillin and amoxicillin respectively. Two cases of meningitis due to isolates of serogroups C and B were reported in two children that were respectively vaccinated using A+C plain saccharide vaccine or two doses of MenBvac vaccine. All patients had received beta-lactamin. Global case fatality rate was 6.6% but was higher (9.9%) for serogroup C than for serogroup B (5.5%) (p=0,007).

CONCLUSION

This study is among the largest series of microbiologically documented meningococcal meningitis to date (more than 1300 cases). In France, meningococal is responsible for 50 % of meningitis. Effective meningococcal serogroup B vaccine and serogroup C vaccination recommendation could lessen considerably the burden of meningococal meningitis.

[Group A streptococcal meningitis in children: clinical characteristics and outcome]

BACKGROUND AND METHOD

Group A streptococcal (GAS) invasive infections have been increasingly reported in recent years but meningitis due to GAS remains a rare affection. In children some scarce case reports have been described. The aim of this study was to describe and analyze the clinical and biological data on GAS meningitis recorded in the Bacterial Meningitis (BM) French Surveillance Network (GPIP/ACTIV).

RESULTS

From 2001 through end 2006, 2539 children suffering from proven bacterial meningitis were recorded in the data base. Among them 10 children presented GAS infections. The mean age was 6 years (9 months to 14.1 years) and the sex ratio (male/female) 4/1. Seven out of the 10 patients had a history of community acquired infection before the onset of GAS meningitis : 3 had previous acute otitis media, 1 otitis media with mastoiditis, 2 sinusitis and 1 soft tissue infection. In the 3 remaining children no risk factors of invasive GAS infection could be identified. All but 1 patient survived. The patient who died had no risk factors for invasive infectious disease. He presented with fulminant septicaemia and died 6hours after hospital admission despite appropriate supportive care and prompt antibiotic treatment. The cerebrospinal fluid examination revealed high white blood cells counts (>500/mm(3)) in 8 patients and Gram stained smear showed gram-positive cocci in 6 patients. All the patients received antibiotic regimen including 3(rd) generation cephalosporins before definite bacterial identification and all the strains were susceptible to the first line antibiotic treatment chosen.

CONCLUSION

GAS is an uncommon organism causing meningitis in children. In our study upper respiratory tract infection is the most common predisposing factor for GAS meningitis but even apparently healthy children can suffer from this severe form of bacterial meningitis.

Effect of Fungicide and Timing of Application on Soybean Rust Severity and Yield

Soybean rust, caused by Phakopsora pachyrhizi, is a devastating foliar disease of soybean that may cause significant yield losses if not managed by well-timed fungicide applications. To determine the effect of fungicide timing on soybean rust severity and soybean yield, field trials were completed in Paraguay (four locations), the United States (two locations), and Zimbabwe (one location) from 2005 to 2006. Treatments at each location included applications of tebuconazole, pyraclostrobin, or a combination of azoxystrobin + propiconazole, and in some locations pyraclostrobin + tebuconazole at the following soybean growth stages (GS): (i) GS R1 (beginning flowering), (ii) GS R3 (beginning pod), (iii) GS R5 (beginning seed), (iv) GS R1 + R3, (v) GS R3 + R5, and (vi) GS R1 + R3 + R5. Soybean yields from plots treated with fungicides were 16 to 114% greater than yields from no fungicide control plots in four locations in Paraguay, 12 to 55% greater in two locations in the United States, and 31% greater in Zimbabwe. In all locations, rust severity measured over time as area under the disease progress curve (AUDPC) was negatively correlated (r = -0.3, P < 0.0001) to yield. The effectiveness of any given treatment (timing of application and product applied) was often dependent on when rust was first detected and the intensity of its development. For example, when soybean rust was first observed before GS R3 (two locations in Paraguay), the plants in plots treated with a fungicide at GS R1 had the lowest AUPDC values and highest yields. When soybean rust was first observed after GS R3, plants treated with a fungicide at GS R3 and/or GS R5 had the lowest AUDPC values and highest yields with a few exceptions.