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1.
The present study was initiated to characterize antibody responses to repetitive epitopes of the circumsporozoite protein (CSP), liver stage antigen-1 (LSA-1), and merozoite surface protein-2 (MSP-2) of Plasmodium falciparum in infants residing in a P. falciparum-hyperendemic area of western Kenya. In this study, development and maintenance of these antibody responses in 28 infants were studied longitudinally by use of monthly serum samples collected from birth to age 1 year. Mother plasma and infant umbilical cord plasma were also tested to assess the transplacental transfer of maternal antibodies. Results showed that antibodies passively transferred from mothers were detectable for CSP, LSA-1, and MSP-2 repeat epitopes. Infants were able to mount and maintain a strong antibody response against LSA-1 in their first year of life. Infants often responded to CSP repeats, but with a much lower antibody titer. Antibody responses in infants against Fc27 and 3D7 repeats of MSP-2 were low throughout their first year. In addition, 51 infants whose first detected infection occurred at > 4 months of age were selected to determine antibody responses to the antigens tested upon their first and second detected infections. Antibody responses to LSA-1 and, to a lesser degree, CSP increased in positivity rates and titer upon second infection. Antibody responses to Fc27-type and 3D7-type repeats of MSP-2 were low upon both infections. There was no association between maternally transferred anti-LSA-1, anti-CSP, or anti-MSP-2 antibodies and an infant's first detected infection. No significant correlation was found between an infant's antibody responses to the 4 antigen repetitive epitopes and protection against malarial parasitemia during the first year of life.  相似文献   

2.
OBJECTIVES: HIV-seropositive pregnant women are more susceptible to malaria than HIV-seronegative women. We assessed whether HIV infection alters maternal and cord plasma malarial antibody responses and the mother-to-infant transfer of malaria antibodies. METHODS: We determined plasma levels of maternal and cord antibodies [Immunoglobulin (IgG)] to recombinant malarial proteins [merozoite surface protein 1 (MSP-1(19kD)), the erythrocyte binding antigen (EBA-175)], the synthetic peptides [MSP-2, MSP-3, rhoptry associated protein 1 (RAP-1), and the pre-erythrocytic stage, circumsporozoite protein (NANP)(5)] antigenic determinants of Plasmodium falciparum; and tetanus toxoid (TT) by ELISA among samples of 99 HIV-seropositive mothers, 69 of their infants, 102 HIV-seronegative mothers and 62 of their infants. RESULTS: The prevalence of maternal antibodies to the malarial antigenic determinants ranged from 18% on MSP3 to 91% on EBA-175; in cord plasma it ranged from 13% to 91%, respectively. More than 97% of maternal and cord samples had antibodies to TT. In multivariate analysis, HIV infection was only associated with reduced antibodies to (NANP)(5) in maternal (P=0.001) and cord plasma (P=0.001); and reduced mother-to-infant antibody transfer to (NANP)(5) (P=0.012). This effect of HIV was independent of maternal age, gravidity and placental malaria. No consistent HIV-associated differences were observed for other antigenic determinants. CONCLUSION: An effect of HIV infection was only observed on one malarial antigenic determinant, suggesting that the increased susceptibility to malaria among HIV-infected pregnant women may not be explained on the basis of their reduced antibody response to malaria antigens.  相似文献   

3.
High levels of antibodies to multiple antigens may be more strongly associated with protection from infection than antibodies to a single antigen. Antibody-associated protection against Plasmodium falciparum infection was assessed in a cohort of 68 adults living in an area of holoendemic malaria in Kenya. Antibodies to the pre-erythrocytic antigens circumsporozoite protein (CSP), liver-stage antigen-1 (LSA-1), thrombospondin-related adhesive protein (TRAP), and blood-stage antigens apical membrane antigen-1 (AMA-1), erythrocyte binding antigen-175 (EBA-175), and merozoite surface protein 1 (MSP-1) were tested. Peptides were used for CSP (NANP repeat) and LSA-1 (central repeat), and recombinant antigens were used for TRAP (aa D(48)-K(394)), AMA-1 (ectodomain, non-glycosylated), EBA-175 (non-glycosylated), and MSP-1 (MSP-1(19)). Weekly microscopy testing for P. falciparum infection was performed over a 12-week period after drug-mediated clearance of P. falciparum parasitemia. Individuals with high levels of IgG antibodies (> 2 arbitrary units) to CSP, LSA-1, and TRAP had a 57% decrease in the risk of infection (95% confidence interval = 20-77%, P = 0.016). This decreased risk remained significant after adjustment for age, prior parasitemia, bed net use, sickle cell trait, and village of residence. In contrast, protection against infection did not correlate with high levels of IgG antibodies to blood-stage antigens or IgM antibodies to pre-erythrocytic or blood-stage antigens. High levels of IgG antibodies to CSP, LSA-1, and TRAP may be useful immune correlates of protection against P. falciparum infection in malaria-endemic populations.  相似文献   

4.
The low birth weight (LBW) infant has a much higher risk of mortality and morbidity in infancy and early childhood. This study examined the effects of maternal HIV infection and other risk factors for LBW (< 2,500 g). A retrospective study of mothers who delivered at Mae Chan Hospital from 1997 to 2002 was conducted. Logistic regression was used to adjust for confounding factors. There were 266 infants born to HIV-seropositive mothers and 5,872 infants born to HIV-negative mothers. Low birth weight was significantly associated with maternal HIV status, gestational age, antenatal care, maternal age less than 20 years, and > 35 years. Maternal HIV positive status, young maternal age and gestational age were significant factors after adjusting for potential confounders. No significant effect of hilltribe on LBW was found. The results underline the need for nutritional surveillance and dietary counseling. HIV-seropositive women must receive early and continuing antenatal care for good pregnancy outcomes.  相似文献   

5.
INTRODUCTION: Young infants are protected from measles infection by maternal measles antibodies. The level of these antibodies at birth depends on the level of antibodies in the mother and the extent of placental transfer. We investigated predictors of levels of measles antibodies in newborns in rural Kenya. METHODS: A total of 747 paired maternal-cord serum samples (91 from human immunodeficiency virus [HIV]-infected and 656 from HIV-uninfected mothers) were tested for measles immunoglobulin G antibodies. Placental malaria infection was determined by biopsy. Data on pregnancy history, gestational age, and anthropometric and socioeconomic status were collected. RESULTS: Infants born to HIV-infected mothers were more likely (odds ratio, 4.6 [95% confidence interval {CI}, 2.2-9.7]) to be seronegative and had 35.1% (95% CI, 9.8%-53.2%) lower levels of measles antibodies than did those born to HIV-uninfected mothers. Preterm delivery, early maternal age, and ethnic group were also associated with reduced levels of measles antibodies. There was little evidence that placental malaria infection was associated with levels of measles antibodies in newborns. CONCLUSION: Our results suggest that maternal HIV infection may reduce levels of measles antibodies in newborns. Low levels of measles antibodies at birth render children susceptible to measles infection at an early age. This is of concern in sub-Saharan African countries, where not only is the prevalence of HIV high, but measles is the cause of much morbidity and mortality.  相似文献   

6.
BACKGROUND: IgG antibodies to pre-erythrocytic antigens are involved in prevention of infection and disease in animal models of malaria but have not been associated with protection against disease in human malaria. METHODS: Levels of IgG antibodies to circumsporozoite protein (CSP), liver-stage antigen type 1 (LSA-1), and thrombospondin-related adhesive protein (TRAP) were measured in 86 children in a malaria-holoendemic area of Kenya. The children were then monitored for episodes of clinical malaria for 52 weeks. RESULTS: Children with high levels of IgG antibodies to CSP, LSA-1, and TRAP had a decreased risk of clinical malaria (adjusted hazard ratio, 0.29; 95% confidence interval 0.10-0.81; P = .02), a lower incidence of clinical malaria (P=.006), protection from clinical malaria with a parasite level of > or =4000 parasites/microL (P= .03), and a higher hemoglobin level at enrollment (P= .009), compared with children with lower antibody levels. Protection against malaria morbidity was associated primarily with antibodies to CSP and LSA-1. CONCLUSIONS: Kenyan children with high levels of IgG antibodies to the pre-erythrocytic antigens CSP, LSA-1, and TRAP have a lower risk of developing clinical malaria than children without high levels of these antibodies. The decreased risk of clinical malaria may be mediated in part by prevention of high-density parasitemia.  相似文献   

7.
Immune responses of 97 Gambian women and their neonates were studied. New methods distinguished between active and previous placental malaria, were used to examine relationships between maternal malaria and neonatal immune responses. Many placentas (61%) had active or previous malarial infection. Maternal and cord malarial IgG levels correlated ( P < 0–001). Malarial IgG was raised in cord blood in active placental malaria; IgM was not detected. Mean lymphoproliferation and the proportion of responders to soluble P. falciparum antigens (F32) and conserved regions of p190 expressed on trophozoites and schizonts (190L and 190N) were higher in neonates than mothers. There was no clear relationship between maternal malaria and neonatal mean lymphoproliferation to malarial antigens, although fewer neonates responded when mothers were actively infected. Matched maternal and neonatal lymphoproliferation responses did not correlate. However, first born neonatal lymphoproliferation to PPD and malarial antigens appeared lower than other neonates, in agreement with lower lymphoproliferation in primigravidae compared with multigravidae. Also in common with mothers, autologous plasma suppressed neonatal lymphoproliferation to PPD and malarial antigens, suggesting common immunoregulation. Higher Cortisol or other circulating factors in first pregnancies may be implicated. The relevance of cell-mediated malarial immune responses detected at birth remains to be established.  相似文献   

8.
This prospective cohort study was conducted to determine the seroconversion rate and the pattern of antibody response to measles vaccine administered at age 9 months in HIV infected and non-infected children born to HIV-1 seropositive mothers. Thirty children born to HIV-1 seropositive mothers and 3 born to HIV-1 seronegative mothers were recruited. One single dose of Schwarz strain of measles virus vaccine (Rouvax) was given to every child at 9 months of age. Clinical status and measles antibody levels were evaluated at the time just before vaccination, 2 and 12 weeks post-vaccination. Antibody was measured by an enzyme immunoassay commercial kit (Enzygnost, Dade Behring Manufacturer, Germany). Children were classified into 3 groups, groups 1 and 2 were children with and without HIV infection respectively. Group 3 children were those born to HIV-1 seronegative mothers. Of the 33 enrolled children, 16, 14 and 3 were classified as groups 1, 2 and 3 respectively. Four children, 2 of each, in groups 1 and 3 did not complete the study. Group 3 was excluded due to the small number of children recruited. There was no short term complication and no measles infection noted during the course of study. None of the children had pre-existing antibodies. The median (range) of CD4 count and CD4/CD8 ratio measured at the time of vaccination were statistically different between groups 1 and 2 children. Group 2 children had better antibody response than group 1 in terms of seroconversion rate and median of antibody levels at 12 weeks post-vaccination. Only 7 of 29 children (24.1%) had detectable measles antibodies at 2 weeks post-vaccination. A decrease in antibody was noted in 2 symptomatic HIV infected children as their disease had progressed. Various potential predictors of measles vaccine responses in HIV infected children including CD4 count and CD4/CD8 ratio were not statistically different between the responders and non-responders. All 4 asymptomatic HIV infected children were responders. This study demonstrated that all of the children had already lost their maternal acquired antibodies at age 9 months. HIV infected children had a poorerantibody response to measles vaccine than the non-infected children.  相似文献   

9.
An increase in illness due to measles is one of the potential consequences of the human immunodeficiency virus (HIV) epidemic in Africa. During a study of perinatal HIV transmission conducted in Kenya, the risk of acquiring measles before vaccination (9 months of age) was found to be 3.8 times higher in infants born to HIV-seropositive mothers than in control infants (10 [9%] of 109 vs. 5 [3%] of 194 infants; P = .02; odds ratio, 3.8; 95% confidence interval, 1.2-13.2). The majority of infants who developed measles in this study had significant sequelae related to their measles infection. The increased risk of measles appeared to be related to relatively lower anti-measles antibody titers detected in cord blood samples of affected infants born to HIV-seropositive mothers. However, 94% of all infants were susceptible to measles on the basis of ELISA testing at age 6 months regardless of maternal HIV serology. These observations highlight the need for improved measles vaccination strategies in Africa and for studies to delineate the effects of HIV infection on the incidence, presentation, and sequelae of childhood infectious illnesses.  相似文献   

10.
BACKGROUND: In clinical trials, maternal tetanus toxoid (TT) vaccination is effective in protecting newborns against tetanus infection, but inadequate placental transfer of tetanus antibodies may contribute to lower-than-expected rates of protection in routine practice. We studied the effect of placental malaria and maternal human immunodeficiency virus (HIV) infection on placental transfer of antibodies to tetanus. METHODS: A total of 704 maternal-cord paired serum samples were tested by ELISA for antibodies to tetanus. The HIV status of all women was determined by an immunoglobulin G antibody-capture particle-adherence test, and placental malaria was determined by placental biopsy. Maternal history of TT vaccination was recorded. RESULTS: Tetanus antibody levels were reduced by 52% (95% confidence interval [CI], 30%-67%) in newborns of HIV-infected women and by 48% (95% CI, 26%-62%) in newborns whose mothers had active-chronic or past placental malaria. Thirty-seven mothers (5.3%) and 55 newborns (7.8%) had tetanus antibody levels <0.1 IU/mL (i.e., were seronegative). Mothers' self-reported history of lack of tetanus immunization was the strongest predictor of seronegativity and of tetanus antibody levels in maternal and cord serum. CONCLUSION: Malarial and HIV infections may hinder efforts to eliminate maternal and neonatal tetanus, making implementation of the current policy for mass vaccination of women of childbearing age an urgent priority.  相似文献   

11.
The role of maternal and pediatric infection with human immunodeficiency virus type 1 (HIV-1) and malaria as risk factors for anemia was determined in a birth cohort of infants born to mothers participating in a study of the interaction between placental malaria and HIV infection, in Kisumu, Kenya. Between June 1996 and April 2000, 661 infants born to 467 HIV-seropositive and 194 HIV-seronegative mothers were monitored monthly from birth. At each visit a questionnaire was completed and a blood sample was collected for the determination of hemoglobin levels and detection of malaria and HIV. Anemia was common and increased from 13.6% at one month to 75% at six months and remained high throughout the second half of infancy. Placental malaria, infant malaria, and HIV infection of the infant were all associated with infant anemia in a multivariate model, adjusting for other co-variates found to be associated with infant anemia. The HIV-infected infants with malaria parasitemia had lower mean hemoglobin levels compared with HIV-uninfected infants, or HIV-infected infants without malaria, suggesting that HIV-infected infants are particularly vulnerable to the adverse consequences of malaria at this age. Early detection and prompt treatment of infant malaria and treatment of anemia as part of the study protocol failed to prevent most of the infants from becoming anemic. Although not proven effective in this study, micronutrient supplementation should be prospectively assessed in HIV-infected infants as a means of preventing anemia.  相似文献   

12.
A child born from a mother with HIV infection was reported. We have followed the patient from 3 month old of age. Her HIV antibody disappeared at 7 month by EIA, and at 10 month by WR. But we confirmed her HIV infection by PCR and HIV culture, repeatedly at those times, PCR and HIV culture are thought to be necessary for sero-negative infants born from mothers positive for HIV antibody.  相似文献   

13.
Maternal HIV-1 and HIV-2 infection and child survival in The Gambia   总被引:2,自引:0,他引:2  
OBJECTIVE: To compare the survival of children born to HIV-1 or HIV-2 seropositive mothers with that of children born to HIV-seronegative mothers and to evaluate risk factors for mortality. DESIGN: Physician-blinded prospective study. METHODS: One hundred and one HIV-1-seropositive, 243 HIV-2-seropositive pregnant women, and 468 HIV-seronegative women (control group) matched by age, parity, and health centre, were followed up in a study of mother-to-child transmission of HIV. Mothers and children were seen at 2 and 6 months of age and subsequently followed at 3-monthly intervals up to 18 months of age. HIV infection in children was diagnosed by polymerase chain reaction at 2, 9 or 18 months and by antibody assays at 18 months. RESULTS: Fifteen per cent of children born to HIV-1-infected mothers died compared with 7% of children born to HIV-2-infected mothers [hazard ratio, 2.3; 95% confidence interval (CI), 1.1-4.7; P = 0.02], and 6% of HIV-seronegative mothers (hazard ratio, 2.6; 95% CI, 1.4-5.0; P = 0.003). Six of the 17 children known to be HIV-1 infected died compared with none among the eight HIV-2-infected children (P = 0.13). High proviral load in the babies, high antenatal maternal RNA plasma viral load, and maternal death increased child mortality significantly. CONCLUSIONS: More children born to HIV-1-infected mothers died in comparison with those born to HIV-2-infected mothers or to mothers from the control group. This effect was due to excess death in HIV-1-infected infants which was associated with a high viral load in the affected mother and child.  相似文献   

14.
To prevent the transmission of HIV infection during the postpartum period, the British HIV Association and Children's HIV Association (BHIVA/CHIVA) continue to recommend the complete avoidance of breast feeding for infants born to HIV-infected mothers, regardless of maternal disease status, viral load or treatment.  相似文献   

15.
Primary infection with adult T-cell leukemia virus (ATLV) was investigated by follow-up studies on 16 ATLV-seropositive mothers and their breastfed infants in an ATLV-endemic area of Japan. Maternal antibody to ATLV decreased in all the infants, and was detectable in only three of 12 infants tested 6 months after birth. Reappearance of the antibody 9-18 months after birth was observed in only four of the 16 infants. The ATLV-bearing cells in peripheral blood were detected in all 16 mothers after delivery. None of the 16 infants showed ATLV-bearing cells in peripheral or cord blood sampled at birth, or 1, 3 or 6 months after birth. However, virus-bearing cells in the blood became detectable 9-18 months after birth in 13 of the 16 infants. Maternal antibody and virus-bearing cells were never detected in a control group of seven infants of ATLV-seronegative mothers. These findings provide evidence for the high incidence of primary ATLV infection during early infancy among infants born to ATLV-seropositive mothers and suggest maternal viral transmission. Furthermore, samples of breast milk from all 12 seropositive mothers examined contained cell-associated ATLV capable of being transmitted to peripheral leucocytes of neonates. This finding suggests that one of the possible maternal transmission routes of ATLV is via breast milk.  相似文献   

16.
Pre-existing antibodies that bind endemic human coronaviruses (eHCoVs) can cross-react with SARS-CoV-2, which is the betacoronavirus that causes COVID-19, but whether these responses influence SARS-CoV-2 infection is still under investigation and is particularly understudied in infants. In this study, we measured eHCoV and SARS-CoV-1 IgG antibody titers before and after SARS-CoV-2 seroconversion in a cohort of Kenyan women and their infants. Pre-existing eHCoV antibody binding titers were not consistently associated with SARS-CoV-2 seroconversion in infants or mothers; however, we observed a very modest association between pre-existing HCoV-229E antibody levels and a lack of SARS-CoV-2 seroconversion in the infants. After seroconversion to SARS-CoV-2, antibody binding titers to the endemic betacoronaviruses HCoV-OC43 and HCoV-HKU1, and the highly pathogenic betacoronavirus SARS-CoV-1, but not the endemic alphacoronaviruses HCoV-229E and HCoV-NL63, increased in the mothers. However, eHCoV antibody levels did not increase following SARS-CoV-2 seroconversion in the infants, suggesting the increase seen in the mothers was not simply due to cross-reactivity to naively generated SARS-CoV-2 antibodies. In contrast, the levels of antibodies that could bind SARS-CoV-1 increased after SARS-CoV-2 seroconversion in both the mothers and infants, both of whom were unlikely to have had a prior SARS-CoV-1 infection, supporting prior findings that SARS-CoV-2 responses cross-react with SARS-CoV-1. In summary, we found evidence of increased eHCoV antibody levels following SARS-CoV-2 seroconversion in the mothers but not the infants, suggesting eHCoV responses can be boosted by SARS-CoV-2 infection when a prior memory response has been established, and that pre-existing cross-reactive antibodies are not strongly associated with SARS-CoV-2 infection risk in mothers or infants.  相似文献   

17.
目的为了解嘉兴市孕产妇艾滋病病毒(HIV)感染状况,探索适合当地的预防艾滋病母婴传播的运行模式和服务方式,最大程度地减少母婴传播。方法对孕产妇检测HIV抗体,初筛阳性标本进行确认试验;对感染HIV的孕产妇进行监测与管理。结果2006—2012年,孕产妇HIV抗体阳性率为0.19‰(57/292507),其中本地户籍为0.02%(3/130 299),流动人口为0.33%0(54/162208),差异有统计学意义(P〈0.01)。分娩的22例活产婴儿中追踪到18个月的有12例,其中11例HIV抗体阴性,1例阳性。结论嘉兴市孕产妇HIV感染处于较低水平,流动人口是艾滋病防治的重点人群。妇幼保健机构和疾病预防控制中心要明确各自职责、加强合作,加强对感染HIV的孕产妇进行监测管理。  相似文献   

18.
目的探讨孕母患自身免疫性甲状腺疾病对婴儿甲状腺功能的影响。方法通过浙江省新生儿疾病筛查网络系统,从2001年7月~2003年6月对78例母亲患自身免疫性甲状腺疾病的婴儿甲状腺功能进行追踪观察,采用病例对照分析的方法对可能影响婴儿甲状腺功能的因素进行非条件logistic回归分析。结果(1)78例孕母患自身免疫性甲状腺疾病的婴儿,其甲状腺功能正常37例,先天性甲低7例,甲亢1例,高TSH血症33例,与同期健康母亲的婴儿相比差异有显著性。(2)经多因素非条件logistic回归分析筛选出孕期母亲甲状腺功能状态、孕母患自身免疫性甲状腺疾病的种类、婴儿体内TSH受体抗体(TRAb)与婴儿甲状腺功能异常有关(均P<0.05)。结论孕母患自身免疫性甲状腺疾病对婴儿甲状腺功能有影响。为减少婴儿甲状腺功能异常的发生率,必须加强孕母妊娠期甲状腺功能的监测。  相似文献   

19.
Infection with HIV as a risk factor for adverse obstetrical outcome   总被引:4,自引:0,他引:4  
We carried out a case-control study to investigate the role of sexually transmitted diseases (STDs), including infection with HIV, as risk factors for adverse outcome of pregnancy. Overall, 1507 women were enrolled within 24 h of delivery. Cases (n = 796) were mothers of low-birthweight infants (less than 2500 g) or of stillborns. Low-birthweight infants were divided into preterms (n = 373) and neonates small for gestational age (n = 234). Stillborns were separated into intrauterine fetal deaths (n = 120), and intrapartum fetal deaths (n = 69). Controls were selected from mothers delivering a live baby of greater than or equal to 2500 g (n = 711). The maternal HIV seroprevalence in the control group was 3.1%. Prematurity was associated with maternal HIV antibody [8.6% seropositive; adjusted odds ratio (OR) 2.1; 95% confidence interval (CI) 1.1-4.0], as was being born small for gestational age (7.7% seropositive; adjusted OR 2.3; 95% CI 1.2-4.2). In mothers who delivered a stillborn baby, both intrauterine fetal death (11.7% seropositive; adjusted OR 2.7; 95% CI 1.3-5.5) and intrapartum fetal death (11.6% seropositive; adjusted OR 2.9; 95% CI 1.3-6.5) were independently associated with HIV seropositivity in the mother. Maternal syphilis was confirmed as an important risk factor for intrauterine fetal death (14.3% positive; adjusted OR 4.8; 95% CI 2.4-9.5). No significant association was found between other STDs, including gonococcal and chlamydial infection, and adverse obstetrical outcome. These results suggest an association between maternal HIV infection and adverse obstetrical outcome, defined as low birthweight and stillbirth.  相似文献   

20.
Maternally transmitted HIV infection in children   总被引:2,自引:0,他引:2  
We evaluated 16 children at high risk for AIDS because of mothers infected with HIV. Two children were persistently seropositive and had laboratory and clinical evidence of HIV infection but had no detectable infectious HIV in their peripheral blood mononuclear cells (PBMC). Seven children, all of whom had clinical and laboratory evidence of HIV infection, were seropositive and virus culture-positive. One child who died at 10 months of age of candida septicemia was HIV antibody-negative but HIV was grown from cultures of his PBMC. Six children had no serologic or virologic evidence of HIV infection; of these, four who were asymptomatic with normal laboratory studies were HIV antibody-positive up to 12 months of age but became antibody-negative by 15 months of age. These observations indicate that: (1) as many as 60% of infants of infected mothers may be infected with HIV; (2) maternal antibody can result in a false-positive or false-negative diagnosis of HIV infection in infants exposed in utero or perinatally, and (3) the use of viral cultures for HIV is valuable for the early diagnosis of maternally transmitted HIV infection.  相似文献   

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