ABSTRACT
Li-ion batteries have empowered consumer electronics and are now seen as the best choice to propel forward the development of eco-friendly (hybrid) electric vehicles. To enhance the energy density, an intensive search has been made for new polyanionic compounds that have a higher potential for the Fe²âº/Fe³âº redox couple. Herein we push this potential to 3.90 V in a new polyanionic material that crystallizes in the triplite structure by substituting as little as 5 atomic per cent of Mn for Fe in Li(Fe(1-δ)Mn(δ))SO4F. Not only is this the highest voltage reported so far for the Fe²âº/Fe³âº redox couple, exceeding that of LiFePO4 by 450 mV, but this new triplite phase is capable of reversibly releasing and reinserting 0.7-0.8 Li ions with a volume change of 0.6% (compared with 7 and 10% for LiFePO4 and LiFeSO4F respectively), to give a capacity of ~125 mA h g⻹.
ABSTRACT
A novel hydrated fluoroselenate NaCoSeO(4)F·2H(2)O has been synthesized, and its structure determined. Like its sulfate homologue, NaCoSO(4)F·2H(2)O, the structure contains one-dimensional chains of corner-sharing MO(4)F(2) octahedra linked together through F atoms sitting in a trans configuration with respect to each other. The magnetic properties of the two phases have been investigated using powder neutron diffraction and susceptibility measurements which indicate antiferromagnetic ordering along the length of the chains and result in a G-type antiferromagnetic ground state. Both compounds exhibit a Néel temperature near 4 K, and undergo a field-induced magnetic phase transition in fields greater than 3 kOe.
ABSTRACT
OBJECTIVES: In France, seton drainage followed by fistulotomy is currently the standard treatment for high cryptoglandular fistula-in-ano. Biological or synthetic glues, such as Glubran(®) 2, have been recently proposed for sealing the fistula tract. The purpose of this study is to determine the healing rate with glubran 2 and to assess the functional outcome after cure of fistula-in-ano. PATIENTS AND METHODS: From July 2006 to July 2008, 34 patients (20 males; median age 48.5 years, range 22-55 years) with high cryptoglandular anal fistulas were treated with glubran 2. Patients were seen for physical examination at 1, 3 and 6 months, then interviewed by telephone at 1 and 2 years, and in September 2009. The Fecal incontinence severity index (FISI) score was used to assess continence. RESULTS: The healing rate at 1 month was 67.6% (23 patients); the fistula failed to heal in 11 patients. All 23 patients with a healed fistula remained recurrence-free, with no continence disorders noted, during the median 34-month follow-up period (range 21-43 months). One patient was lost to follow-up after 6 months. CONCLUSION: Glubran 2 provides an effective treatment for high fistula-in-ano, with no change in continence. In future, a randomized comparison of this agent with fibrin glues should be useful.
Subject(s)
Cutaneous Fistula/surgery , Cyanoacrylates/therapeutic use , Rectal Fistula/surgery , Tissue Adhesives/therapeutic use , Adult , Aged , Aged, 80 and over , Cyanoacrylates/adverse effects , Fecal Incontinence/prevention & control , Female , Humans , Male , Middle Aged , Pain/etiology , Patient Preference , Postoperative Complications/etiology , Tissue Adhesives/adverse effects , Treatment Outcome , Young AdultABSTRACT
Li-ion batteries have contributed to the commercial success of portable electronics, and are now in a position to influence higher-volume applications such as plug-in hybrid electric vehicles. Most commercial Li-ion batteries use positive electrodes based on lithium cobalt oxides. Despite showing a lower voltage than cobalt-based systems (3.45 V versus 4 V) and a lower energy density, LiFePO(4) has emerged as a promising contender owing to the cost sensitivity of higher-volume markets. LiFePO(4) also shows intrinsically low ionic and electronic transport, necessitating nanosizing and/or carbon coating. Clearly, there is a need for inexpensive materials with higher energy densities. Although this could in principle be achieved by introducing fluorine and by replacing phosphate groups with more electron-withdrawing sulphate groups, this avenue has remained unexplored. Herein, we synthesize and show promising electrode performance for LiFeSO(4)F. This material shows a slightly higher voltage (3.6 V versus Li) than LiFePO(4) and suppresses the need for nanosizing or carbon coating while sharing the same cost advantage. This work not only provides a positive-electrode contender to rival LiFePO(4), but also suggests that broad classes of fluoro-oxyanion materials could be discovered.
ABSTRACT
PURPOSE: Few therapeutic tools are available for treating idiopathic anal incontinence. Sacral neuromodulation appears to be effective in selected patients but requires surgical implantation of a permanent electrical stimulator. The aim of this work was to assess the efficiency of posterior tibial nerve (PTN) transcutaneous electrical nerve stimulation (TENS) in the treatment of anal idiopathic incontinence. METHODS: Ten women were treated by PTN TENS, 20 min a day for 4 weeks. Functional results were evaluated by Wexner's incontinence score and anorectal manometry. RESULTS: Eight of the ten patients showed a 60% mean improvement of their incontinence score after 4 weeks. This improvement remained stable over the 12-week follow-up period. Manometric parameters did not differ before and after stimulation. CONCLUSION: PTN neuromodulation without surgically implanted electrode could represent a safe and low-cost alternative to permanent sacral neuromodulation for idiopathic anal incontinence.
Subject(s)
Fecal Incontinence/therapy , Transcutaneous Electric Nerve Stimulation/methods , Adult , Aged , Female , Humans , Male , Manometry , Middle Aged , Tibial NerveSubject(s)
HTLV-I Infections/epidemiology , HTLV-I Infections/transmission , HTLV-II Infections/epidemiology , HTLV-II Infections/transmission , Adolescent , Adult , Breast Feeding , Female , Gambia/epidemiology , HTLV-I Antibodies/blood , HTLV-I Infections/immunology , HTLV-II Antibodies/blood , HTLV-II Infections/immunology , Humans , Infant , Infectious Disease Transmission, Vertical , Male , Maternal-Fetal Exchange , Middle Aged , Milk, Human/microbiology , Pregnancy , Seroepidemiologic StudiesABSTRACT
An intervention study was done over two years in seven Gambian villages to determine the contribution of bedbugs to hepatitis B transmission. In addition, fortnightly questionnaires were completed for each child to assess other possible routes of transmission. The intervention, insecticide spraying of the child's dwelling, was highly effective in reducing exposure to bedbugs but there was no effect on hepatitis B infection. No other risk factor for transmission was identified despite a consistent village-to-village variation in the rate of childhood infection. The major mode of transmission of hepatitis B in childhood remains unknown.
Subject(s)
Bedbugs/microbiology , Hepatitis B/prevention & control , Hepatitis B/transmission , Insect Vectors , Animals , Child, Preschool , Cross-Sectional Studies , Female , Gambia , Humans , Infant , Insect Control , Insecticides , Logistic Models , Male , Permethrin , PyrethrinsABSTRACT
Because of the high prevalence of hepatitis B virus (HBV) infection in The Gambia, HBV vaccination has been incorporated into the national expanded programme on immunisation. We have assessed the efficacy of the vaccine against HBV infection and chronic carriage by examining 720 3-4-year-old children who had received the vaccine in infancy and 816 who had not received it. The vaccine was 84% (95% CI 78-89%) effective against infection and 94% (84-98%) effective against chronic carriage. Vaccinated infants of mothers positive for hepatitis B surface and e antigens were at greater risk of breakthrough infection and chronic carriage than infants of uninfected mothers. The high vaccine efficacy against the HBV carrier state, the main risk factor for the development of chronic liver disease and liver cancer, offers hope that the prevalence of these diseases may be reduced in the future.
PIP: As part of the Gambia Hepatitis Intervention Study, hepatitis B antigens and antibodies were assayed in 720 3-4 year old children who had received 4 doses of 10 mcg plasma-derived hepatitis B vaccine in infancy, the findings were compared with 816 controls. The cross sectional study took place from September, 1990, to July, 1991. Study subjects were tested for hepatitis B core antigen (HBcAg), as well as antigens and antibodies to hepatitis surface, e, and core protein, and those testing positive were tested a year later for HBsAg to determine chronic carrier status. Children negative for core antibody and surface antigen were considered uninfected; those positive for core antibody were considered infected; those positive for surface antigen 2 times 6 months apart were considered carriers. 4.6% of the vaccinated children were infected, and 0.6% were chronic carriers. 3 of these carriers had infected or carrier mothers, and 1 had only received 1 dose of vaccine. In the controls, there were 29% judged infected by anti-HBc, including 13% who were also positive for HBsAg. 86% of these were considered chronic carriers when tested a year later. Thus the vaccine was estimated to be 84% effective against infection and 94% effective against chronic carriage. The current Gambian vaccine consists of 2.5 mcg recombinant hepatitis B vaccine.
Subject(s)
Hepatitis B Vaccines/administration & dosage , Hepatitis B/prevention & control , Vaccination , Carrier State/prevention & control , Child, Preschool , Gambia/epidemiology , Hepatitis B/epidemiology , Hepatitis B Antibodies/analysis , Hepatitis B Core Antigens/immunology , Hepatitis B Surface Antigens/analysis , Hepatitis B Vaccines/immunology , HumansABSTRACT
Hepatitis B vaccine has been introduced into The Gambia's national Expanded Programme on Immunization, with the aim of evaluating the impact on chronic liver diseases and in particular on hepatocellular carcinoma. As part of the project, a cohort of 1000 children was recruited to assess the long-term protection induced by the vaccine. The first 3 years of follow-up are described. By the age of 3 years, 95% of the children had protective antibody levels; 4 (0.6%) are known to be carriers in contrast to the 90-140 that would be expected in the absence of vaccination. The protective effectiveness of vaccine in preventing chronic carriage in the first 3 years of life is thus estimated as 95%. Since the risk of becoming a carrier is highest in those infected early in life, these results are encouraging.
Subject(s)
Hepatitis B/prevention & control , Viral Hepatitis Vaccines/administration & dosage , Antigens, Viral/analysis , Child, Preschool , Cohort Studies , Follow-Up Studies , Gambia , Hepatitis B/epidemiology , Hepatitis B/immunology , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines , Humans , Immunization Schedule , Infant , Risk Factors , Viral Hepatitis Vaccines/immunologyABSTRACT
A seroepidemiological study was conducted, during 1988 and 1989, of mother-child pairs living in The Gambia (West Africa) in order to determine the distribution of the human immunodeficiency viruses type 1 (HIV-1) and type 2 (HIV-2). Specimens were obtained from 931 children (age range, 14-17, months) and 923 mothers (age range, 14-17 years) using village-based cluster samples; the children are participating in The Gambia Hepatitis Intervention Study (GHIS), a large-scale HBV vaccination program. Large numbers of indeterminate Western blot patterns were observed among the mothers, mainly for HIV-1 antibodies; HIV-1 infected subjects were not found, whereas an HIV-2 seroprevalence rate of 0.75% was observed. The children born to the seven HIV-2 positive women were seronegative for HIV-2 antibodies, and none of the children showed HIV-2 or HIV-1 seropositively.
Subject(s)
Family Health , HIV Seroprevalence , HIV-1/immunology , HIV-2/immunology , Adolescent , Adult , Age Factors , Blotting, Western , Female , Gambia/epidemiology , Humans , Infant , Middle AgedABSTRACT
Data on over a thousand Gambian children have been analysed to examine factors influencing their antibody levels following immunization with hepatitis B vaccine administered during the first year of life. The dominant effect was the time between the last dose of vaccine and taking the blood sample. There was considerable variation in vaccine response by area of residence which could not be explained by any other factor. The hepatitis B surface antigen (HBsAg) status of the mother and the age at vaccination did not appear to have an effect, but there was some indication that a delay in receiving the second dose of vaccine led to a marginally lower response.
PIP: As part of The Gambia Hepatitis Intervention Study, researchers took blood samples from 1000 12-18 month old infants from 4 distinct parts of The Gambia who had received the hepatitis B (HB) vaccine to examine HB markers to define factors which influence their response to immunization. 62% of the children had high antibody levels of 1000 mIU/ml compared to only 2% who did not respond to the vaccine (10 mIU/ml). Only .6% of the vaccinated children tested positive for HB surface antigen compared to 7% of unvaccinated children in a previous study in The Gambia. Therefore the vaccination was effective in preventing the carrier state. Time between immunization and bleeding strongly influenced the antibody level (p.001). Indeed a 47% reduction in the level of antibody occurred after 30 days. Nevertheless the antibody level remained high after 12 months, again giving credence to the vaccine's ability to prevent the carrier state. Residence was substantially associated with antibody level (p.01). The differences could not be attributed to ethnic differences, seasonal variation, season of birth, or season of 1st immunization. Specifically, children in Essay in the western section of The Gambia had the highest antibody levels followed by those in Brikama, Badjakunda and Yorobawal, and the Dankunku and Kudang. The greater the interval between the 1st and 2nd doses the lower the antibody response (p=.03). For example, the recommended interval between the 2 doses is 4 weeks, but in those cases where the interval was doubled the antibody response fell 12%. On the other hand, increasing the interval between the 2nd and 3rd doses or the 3rd and the 4th doses die not affect antibody level.
Subject(s)
Hepatitis B virus/immunology , Viral Hepatitis Vaccines/immunology , Antibodies, Viral/immunology , Child, Preschool , Gambia , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines , Humans , Immunization Schedule , Infant , Viral Hepatitis Vaccines/administration & dosageABSTRACT
The influence of the hepatitis B status of family members on the response to hepatitis B vaccine of an infant has been examined in 395 families. The presence of one or more HBsAg-positive family members did not appear to have any effect on the vaccine response. This is an encouraging finding as children born into carrier families are at an increased risk of becoming carriers themselves. That the vaccine response of such children is as good as for those born into non-carrier families means that they are likely to be protected against the carrier state by the vaccine.
PIP: As part of The Gambia Hepatitis Intervention Study (designed to protect children from hepatitis and therefore liver cancer when adults), researchers took blood samples from at least 291 families of 293 index children from Brikama in the western region and 2 neighboring health centers in the Upper River Division (URD) in the eastern area of The Gambia who had received the hepatitis B virus (HBV) vaccine to examine vaccine response in infants in relation to the pattern of HBV infection in their families. 1 family member tested positive for hepatitis B surface antigen (HBsAg) in at least 30% of the children. The researchers did not find a correlation between the level of antibody in the index children and the HBsAg status of the family. 23% of families in Brikama had at least 1 HBsAg positive member compared to 37% in URD (p=.01). Even though no association existed between child's response to the vaccine and type of dwelling, an association did exist between HBsAg positive family members and type of dwelling. 35% of families who lived in a house constructed of mud or grass had at least 1 HbsAG positive family member whereas only 19.7% who lived in a concrete house had at least 1 HBsAg positive family member (p.02). Further, 40.8% of families who lived under a thatched roof had at least 1 HbsAg positive family member compared to 24.8% who had a corrugated roof (p.02). The researchers suggested that houses constructed of mud or grass or with a thatched roof may harbor more insects which transmit HBV. The socioeconomic factors of sanitation and water supply did not contribute to HBV infection. They concluded that the HBV status of a child's family did not affect his/her response to the vaccine. Therefore the vaccine protects children at high risk of becoming HBV carriers.
Subject(s)
Hepatitis B/immunology , Viral Hepatitis Vaccines/immunology , Family , Gambia , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines , Humans , InfantABSTRACT
Risk factors for hepatitis B virus transmission were examined in 973 Gambian children aged 6 months to 5 years. 33% had evidence of infection with hepatitis B virus and a third of these were carriers. A significant association was found between infection and tropical ulcer scars, and between e antigenaemia and the presence of bedbugs in each child's bed. There was no association between infection and traditional scarring, circumcision, or injections. Skin disease and arthropods are the two most likely modes of transmission of hepatitis B virus between children in West Africa.
Subject(s)
Hepatitis B/transmission , Acute Disease , Adult , Animals , Bedbugs/microbiology , Carrier State/epidemiology , Carrier State/immunology , Carrier State/microbiology , Child, Preschool , Female , Gambia/epidemiology , Hepatitis B/epidemiology , Hepatitis B/immunology , Hepatitis B/microbiology , Hepatitis B Antibodies/analysis , Hepatitis B Surface Antigens/immunology , Hepatitis B e Antigens/immunology , Humans , Infant , Male , Risk Factors , Skin Diseases/complications , Skin Diseases/epidemiology , Skin Diseases/immunology , Skin Diseases/microbiology , Space-Time Clustering , Ticks/microbiologyABSTRACT
A new type of hepatitis B virus (HBV) infection has been encountered in Senegalese infants and French adults characterized by serum hepatitis B surface antigen (HBsAg) without antibodies to the core antigen (anti-HBc). As the infection is not associated with the presence of the e antigen, it differs from HBV in its core antigen. After the loss of HBsAg, neither anti-HBc nor antibodies to HBsAg (anti-HBs) become detectable. This new infection (called HBV2 as opposed to the classical HBV1 infection) was found in infants with anti-HBs, either naturally acquired or produced by immunization against HBV. The use of monoclonal anti-HBs antibodies showed that two epitopes of HBV1 surface antigen could be detected in HBV2-positive sera. HBV DNA sequences could only be found in one of 15 HBV2-infected children using a DNA-DNA hybridization procedure; low levels of HBV DNA were also detected in 58% of the HBsAg-positive adult sera tested. If this new infection, apparently related to HBV1, is shown to cause chronic liver disease, hepatitis B vaccine should also contain surface antigen from HBV2.
Subject(s)
Hepatitis B Surface Antigens/immunology , Hepatitis B virus/immunology , Hepatitis B/immunology , Adult , Child , Child, Preschool , Cross Reactions , DNA, Viral/analysis , France , Genetic Variation , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Hepatitis B e Antigens/analysis , Hepatitis B virus/genetics , Humans , Infant , SenegalABSTRACT
Immunization against hepatitis B by means of a vaccine obtained by genetic recombination on chinese hamster ovary cells was attempted in 32 adult subjects. The HBs antigen was purified from the culture supernatant and contained S and pre S2 genes products. Three 20 micrograms doses were injected intramuscularly at intervals of one month. Anti-HBs seroconversion levels and the geometrical mean of antibodies were slightly higher than those observed with plasma vaccines or genetically engineered yeast-derived vaccine. Antibodies directed against HBs appeared more rapidly and at a higher titre. Anti-pre S2 antibodies were detected after the third injection in 84 per cent of the subjects vaccinated. This recombinant hepatitis B vaccine prepared from chinese hamster ovary cells will probably be as effective as the first generation vaccines obtained by purifying the HBs antigen obtained from the blood of asymptomatic carriers.
Subject(s)
Hepatitis B virus/immunology , Viral Vaccines/immunology , Adult , Female , Genes, Viral , Hepatitis B Antibodies/analysis , Hepatitis B virus/genetics , Humans , Male , Recombination, GeneticABSTRACT
A viral infection characterised by serum HBsAg positivity with serum anti-HBc negativity has been encountered in Senegal. The infection is not associated with the presence of HBeAg, so it differs from hepatitis B virus in its core antigen, but the surface antigen of the two viruses share some epitopes. After the loss of HBsAg, neither anti-HBc nor anti-HBs becomes detectable. Anti-HBs, naturally acquired or produced by immunisation, does not protect against this new infection. Chronic carriage occurs. If this new infection is confirmed to cause chronic liver disease, hepatitis B vaccine should include surface antigen from the new virus.
Subject(s)
Hepatitis B Surface Antigens/analysis , Hepatitis B virus/immunology , Hepatitis, Viral, Human/immunology , Carrier State/immunology , Child , Child, Preschool , DNA, Viral/analysis , Enzyme-Linked Immunosorbent Assay , Epitopes , Follow-Up Studies , Hepatitis B Antibodies/analysis , Hepatitis B Core Antigens/analysis , Hepatitis B Vaccines , Hepatitis, Viral, Human/epidemiology , Hepatitis, Viral, Human/prevention & control , Humans , Immunization , Nucleic Acid Hybridization , Senegal , Viral Hepatitis Vaccines/immunologyABSTRACT
Persistence of anti-HBs in 156 Senegalese infants immunized with hepatitis B vaccine was studied for periods ranging from 2 to 6 years after booster dose administration. Six years after the booster dose, 90.4% of the infants had detectable anti-HBs antibodies, with 78.1% having titers higher than 10 mIU/ml. The geometric mean titer was 60 mIU/ml. Females showed higher anti-HBs values than males. In a group of 11 infants who received no booster dose, anti-HBs antibodies were detectable 7 years after the first dose. However, the geometric mean titer was lower (26 mIU/ml). Revaccination (56 infants) led to an increase of the geometric mean titer to 469 mIU/ml 2 months later. These results show that a booster injection every 5-6 years should provide adequate protective anti-HBs levels in infants.
Subject(s)
Antibodies, Viral/analysis , Hepatitis B/prevention & control , Immunization, Secondary , Child , Female , Humans , Male , Sex Characteristics , VaccinationABSTRACT
This report concerns hepatitis B virus (HBV) infections observed in 155 infants from Senegal, studied with a view to determining the factors involved in development of the chronic carrier state. A chronic carrier state was observed in 50.3% of the infants. This study confirms that the risk of chronic carriage is linked to age. This risk declines very rapidly with age, falling from 82% in infants under 6 months old, to 15% in children between the ages of 2 and 3 years. Spontaneous elimination of hepatitis B surface antigen (HBsAg) is uncommon in HBsAg carriers during childhood. The difference observed in chronic carriage between males and females is due to a difference in susceptibility of the two sexes to the development of the chronic carrier state: HBV infections (before 2 years of age) lead to a chronic carriage in 77% of males as against 50% of females. These conclusions are important in view of the immunisation programs being carried out against hepatitis B virus in endemic areas. For a maximum efficacy, vaccination must be carried out at birth, or shortly afterwards.
Subject(s)
Carrier State/epidemiology , Hepatitis B/epidemiology , Age Factors , Child , Child, Preschool , Female , Hepatitis B Antibodies/analysis , Hepatitis B Surface Antigens/analysis , Humans , Infant , Male , Risk , Senegal , Sex FactorsABSTRACT
A booster dose of hepatitis B vaccine was given to 143 children in whom hepatitis B had not developed 1 year after initial vaccination. Over the next six years the incidence of hepatitis B in this group was 1.5% per year compared with 11.5% per year in a similar group of unvaccinated children. In the first 4 years the protective efficacy of the vaccine was 100%, but during the 5th and 6th years it fell to 67%. For maximum protection a second booster is needed, 5 years after the first.