Control of parasite replication exerted by MHC class I restricted CD8+ T-cells in the liver is critical for vaccination-induced protection against malaria. While many intracellular pathogens subvert the MHC class I presentation machinery, its functionality in the course of malaria replication in hepatocytes has not been characterized. Using experimental systems based on specific identification, isolation and analysis of human hepatocytes infected with P. berghei ANKA GFP or P. falciparum 3D7 GFP sporozoites we demonstrated that molecular components of the MHC class I pathway exhibit largely unaltered expression in malaria-infected hepatocytes until very late stages of parasite development. Furthermore, infected cells showed no obvious defects in their capacity to upregulate expression of different molecular components of the MHC class I machinery in response to pro-inflammatory lymphokines or trigger direct activation of allo-specific or peptide-specific human CD8+ T-cells. We further demonstrate that ectopic expression of circumsporozoite protein does not alter expression of critical genes of the MHC class I pathway and its response to pro-inflammatory cytokines. In addition, we identified supra-cellular structures, which arose at late stages of parasite replication, possessed the characteristic morphology of merosomes and exhibited nearly complete loss of surface MHC class I expression. These data have multiple implications for our understanding of natural T-cell immunity against malaria and may promote development of novel, efficient anti-malaria vaccines overcoming immune escape of the parasite in the liver.

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INTRODUCTION: Many forms of contraception are female-dependent and may not be evident to sexual partners. Less than half of men who are sexually active but do not want to father a child have partners who consistently use contraception. This study examines whether male knowledge of his partner’s birth control method is associated with having impregnated a partner. METHODS: We used data from the 2011-2013 National Surveys of Family Growth. Our sample included sexually active men 15-45 years of age who had never been married. Unadjusted t-tests and linear regression assessed whether knowledge of his last partner’s birth control method was associated with having fathered a pregnancy. RESULTS: Our sample included 1,845 males. 477 (25.85%) had fathered a pregnancy. At last sexual intercourse, 45.20% (n=834) reported that their partner used female-dependent contraception, defined as a contraceptive method other than male condoms, withdrawal or male sterilization. 49.70% (n=917) reported that their partner did not use female-dependent contraception, and 5.09% (n=94) did not know what contraception, if any, their partner used. There were no significant differences in rates of having fathered a pregnancy in unadjusted comparisons between groups. When adjusting for age, number of sexual partners, use of male-dependent contraception, and knowledge of contraception prior to first sex there remained no statistically significant association between male’s knowledge of his partner’s contraceptive method and having fathered a pregnancy. CONCLUSION: Among unmarried men, knowledge of a current partner’s contraceptive method is not significantly associated with having fathered a pregnancy.

INTRODUCTION: The November 2017 American College of Obstetricians and Gynecologists (ACOG) Practice Bulletin No. 186 states that an intrauterine contraceptive (IUC) can be inserted “at any time during the menstrual cycle as long as pregnancy may be reasonably excluded”. However, many providers insert IUCs during menstruation to ensure that a woman is not pregnant and because of a belief that this timing leads to easier insertions. A delay in insertion may be an obstacle to access. This study aims to evaluate if menstruation decreases the rate of difficult insertions. METHODS: We conducted a retrospective chart review of 250 women with IUC insertions in our Gynecology outpatient clinic within 5 days of the start of last menstrual period (LMP) compared to women with insertion outside of menses. Difficult insertions were defined as an initial failed attempt at placement, need for additional dilation, need for pharmacologic cervical preparation, need for second provider, or need for ultrasound guidance. RESULTS: IUCs were inserted within 5 days of LMP in 18.8% of patients (n = 47). The overall difficult insertion rate was 10.0% (n = 25) with 4 failed placements (1.6%). For insertions within 5 days of LMP, 17.0% were difficult compared to 8.4% for insertions not within 5 days of LMP. CONCLUSION: Our results indicate that IUC insertion within 5 days of LMP is not associated with a higher rate of difficult placements. Changing practice patterns to encourage interval IUC insertion would decrease the barrier of timing for women seeking a long-acting form of contraception.