138 research outputs found
Genital trauma due to coital injury in women at Pikine National Hospital: epidemiological, diagnostic, and therapeutic insights from 32 cases
Background: Sexual trauma involves very different situations in women, most of which are uncommon in clinical practice. These are, often minor lesions following “normal” sexual act, not requiring medical attention. In general, it is estimated at less than 1% of gynecological emergencies.
Methods: This is a retrospective, descriptive and analytical study which extends over a period from March 2019 to January 2023, i.e., a duration of 3 years and 10 months.
Results: During the study period, 32 cases of per coital trauma were collected out of a total of 18,924 gynecological and obstetrical emergencies, i.e., a frequency of 0.16%. The 20–40-year-old age group was the most represented with a rate of 72.7% and most of them were married (72.7%).
The trauma occurred during consensual sexual intercourse with a male, rate of 75.8% compared to 24.2% of non-consensual reports. It was the first sexual act in 69.7% of cases and mainly occurred at night (72.7%). Patients mainly consulted for vaginal bleeding. The relationship between the type of lesion and parity as well as that between the type of lesion and the circumstances of occurrence showed that complex lesions were more frequently encountered in nulliparous women during consensual sexual act.
Conclusions: Percoital genital trauma in women remains an under-reported condition despite the enormous risks to the vital, but also functional and psychological prognosis
Fonctionnement Hydrique du Baobab (Adansonia digitata L.) en Moyenne et Haute Casamance (Sénégal)
Cette étude aborde le fonctionnement hydrique du baobab afin de mieux appréhender ses relations en eau avec ses phases phénologiques et l’effet induit par les saisons climatiques et de celui de la toposéquence. Pour cela, l’humidité du sol, la teneur relative en eau (TRE) et le potentiel hydrique foliaire (Ψ) ont été étudiés. Les données ont été collectées sur deux sites, en plateau et dans le bas-fond, en saison sèche chaude (SSC), en pleine saison des pluies (PSP) et en saison sèche fraiche (SSF). La SSC correspond à l’apparition des premières feuilles. La PSP correspond à la pleine feuillaison et la fin de la floraison et au début de la fructification. La SSF correspond à la maturation avancée des fruits et à la pleine chute des feuilles. Le logiciel R version 3.4.2 a été utilisé pour traiter les données. Il a permis d’effectuer des tests pour l’analyse des données. Les résultats montrent une variation saisonnière de l’humidité du sol autour de la zone racinaire du baobab. En effet, en SSC, l’humidité du sol est à son niveau le plus faible contrairement en MSP et en SSF. Cependant, la faible disponibilité en eau du sol en SSC n’empêche pas l’état hydrique interne du baobab d’être élevé. En effet, espèce caduque à tronc succulent, les Ψ et les TRE trouvés du baobab sont plus élevés en saison sèche qu’en saison pluvieuse. Egalement, en fonction des saisons climatiques, les différences obtenues sur les Ψ d’une part, et sur les TRE d’autre part, sont statistiquement significatives (P<0,05) sur le plateau contrairement au bas-fond. Ce dernier bénéficie des conditions hydriques du sol plus favorables pendant la saison sèche, ce qui a probablement minimisé ces différences, d’où le rôle important de la toposéquence sur la recharge de l’eau du sol. Ces résultats sont importants dans le but de mieux encourager la propagation les plantations de baobab grâce à sa capacité d’adaptation aux saisons climatiques et au milieu, et de sa tolérence à la sècheresse saisonnière du sol, afin de palier la dégradation de la ressource et faire face aux effets du changement climatique. This study deals with the baobab's water functioning in order to better understand its water relations with its phenological phases and the effect induced by the climatic seasons and that of the toposequence. For this, the soil moisture, the relative water content (TRE) and the leaf water potential (Ψ) were studied. Data were collected at two sites, in the upland and in the lowland, in the hot dry season (SSC), in the middle of the rainy season (PSP) and in the cool dry season (SSF). SSC corresponds to the appearance of the first leaves. The PSP corresponds to full leafing and the end of flowering and early fruiting. SSF is the advanced ripening of fruits and the full fall of leaves. The R version 3.4.2 software was used to process the data. It allowed to test the data analysis. The results show a seasonal variation ofsoil moisture around the baobab root zone. Indeed, in SSC, soil moisture is at its weakest level, unlike in MSP and SSF. However, the low water availability of soil in SSC does not prevent the internal water condition of baobab from being high. Indeed, succulent trunk deciduous species, Ψ and TRE found baobab are higher in the dry season than in the rainy season. Also, according to the climatic seasons, the differences obtained on Ψ on the one hand, and on the TREs on the other hand, are statistically significant (P <0.05) on the upland contrary to the lowland. The latter benefits from more favorable soil moisture conditions during the dry season, which probably minimized these differences, hence the important role of toposequence on groundwater recharge. These results are important in order to better encourage the spread of baobab plantations through its ability to adapt to the climatic seasons and the environment, and its tolerance of seasonal soil drought, in order to mitigate the degradation of the resource and cope with the effects of climate change
Bliss' and Loewe's additive and synergistic effects in Plasmodium falciparum growth inhibition by AMA1-RON2L, RH5, RIPR and CyRPA antibody combinations
Plasmodium invasion of red blood cells involves malaria proteins, such as reticulocyte-binding protein homolog 5 (RH5), RH5 interacting protein (RIPR), cysteine-rich protective antigen (CyRPA), apical membrane antigen 1 (AMA1) and rhoptry neck protein 2 (RON2), all of which are blood-stage malaria vaccine candidates. So far, vaccines containing AMA1 alone have been unsuccessful in clinical trials. However, immunization with AMA1 bound with RON2L (AMA1-RON2L) induces better protection against P. falciparum malaria in Aotus monkeys. We therefore sought to determine whether combinations of RH5, RIPR, CyRPA and AMA1-RON2L antibodies improve their biological activities and sought to develop a robust method for determination of synergy or additivity in antibody combinations. Rabbit antibodies against AMA1-RON2L, RH5, RIPR or CyRPA were tested either alone or in combinations in P. falciparum growth inhibition assay to determine Bliss' and Loewe's additivities. The AMA1-RON2L/RH5 combination consistently demonstrated an additive effect while the CyRPA/RIPR combination showed a modest synergistic effect with Hewlett’s =1.07[95%CI:1.03,1.19]. Additionally, we provide a publicly-available, online tool to aid researchers in analyzing and planning their own synergy experiments. This study supports future blood-stage vaccine development by providing a solid methodology to evaluate additive and/or synergistic (or antagonistic) effect of vaccine-induced antibodies
Antibodies from malaria-exposed Malians generally interact additively or synergistically with human vaccine-induced RH5 antibodies
Reticulocyte-binding protein homolog 5 (RH5) is a leading Plasmodium falciparum blood-stage vaccine candidate. Another possible candidate, apical membrane antigen 1 (AMA1), was not efficacious in malaria-endemic populations, likely due to pre-existing antimalarial antibodies that interfered with the activity of vaccine-induced AMA1 antibodies, as judged by in vitro growth inhibition assay (GIA). To determine how pre-existing antibodies interact with vaccine-induced RH5 antibodies, we purify total and RH5-specific immunoglobulin Gs (IgGs) from malaria-exposed Malians and malaria-naive RH5 vaccinees. Infection-induced RH5 antibody titers are much lower than those induced by vaccination, and RH5-specific IgGs show differences in the binding site between the two populations. In GIA, Malian polyclonal IgGs show additive or synergistic interactions with RH5 human monoclonal antibodies and overall additive interactions with vaccine-induced polyclonal RH5 IgGs. These results suggest that pre-existing antibodies will interact favorably with vaccine-induced RH5 antibodies, in contrast to AMA1 antibodies. This study supports RH5 vaccine trials in malaria-endemic regions
Comparison of Biological Activity of Human Anti-Apical Membrane Antigen-1 Antibodies Induced by Natural Infection and Vaccination
Abstract
Vaccines represent a significant potential means of decreasing global morbidity and mortality due to malaria. Clinical trials in the United States with Plasmodium falciparum Apical Membrane Antigen 1 (AMA1) showed that the vaccine induced biologically active Abs judged by an in vitro parasite growth inhibition assay (GIA). However, the same vaccine in Malian adults did not increase biological activity, although it elevated ELISA titers. Because GIA has been used to evaluate the biological activity of Abs induced by blood stage malarial vaccine candidates, we explored this discrepancy in this study. We affinity purified AMA1-specific Abs from both U.S. vaccinees and nonvaccinated individuals living in a malaria-endemic area of Mali and performed ELISA and GIA. Both AMA1-specifc Abs induced by vaccination (U.S.) and by natural infection (Mali) have comparable biological activity in GIA when the ELISA titer is normalized. However, a fraction of Malians’ IgG that did not bind to AMA1 protein (Mali-non-AMA1 IgG) reduced the biological activity of the AMA1 Abs from U.S. vaccinees; in contrast, U.S.-non-AMA1 IgGs did not show a reduction of the biological activity. Further investigation revealed that the reduction was due to malaria-specific IgGs in the Mali-non-AMA1 IgGs. The fact that both U.S.- and Mali-AMA1-specific Abs showed comparable biological activity supports further development of AMA1-based vaccines. However, the reduction of biological activity of AMA1-specific Ab by other malaria-specific IgGs likely explains the limited effect on growth-inhibitory activity of Abs induced by AMA1 vaccination in Malian adults and may complicate efforts to develop a blood stage malaria vaccine.</jats:p
Superior antibody immunogenicity of a viral-vectored RH5 blood-stage malaria vaccine in Tanzanian infants as compared to adults
Background: RH5 is a leading blood-stage candidate antigen for a Plasmodium falciparum vaccine; however, its safety and immunogenicity in malaria-endemic populations are unknown.
Methods: A phase 1b, single-center, dose-escalation, age-de-escalation, double-blind, randomized, controlled trial was conducted in Bagamoyo, Tanzania (NCT03435874). Between 12th April and 25th October 2018, 63 healthy adults (18–35 years), young children (1–6 years), and infants (6–11 months) received a priming dose of viral-vectored ChAd63 RH5 or rabies control vaccine. Sixty participants were boosted with modified vaccinia virus Ankara (MVA) RH5 or rabies control vaccine 8 weeks later and completed 6 months of follow-up post priming. Primary outcomes were the number of solicited and unsolicited adverse events post vaccination and the number of serious adverse events over the study period. Secondary outcomes included measures of the anti-RH5 immune response.
Findings: Vaccinations were well tolerated, with profiles comparable across groups. No serious adverse events were reported. Vaccination induced RH5-specific cellular and humoral responses. Higher anti-RH5 serum immunoglobulin G (IgG) responses were observed post boost in young children and infants compared to adults. Vaccine-induced antibodies showed growth inhibition activity (GIA) in vitro against P. falciparum blood-stage parasites; their highest levels were observed in infants.
Conclusions: The ChAd63-MVA RH5 vaccine shows acceptable safety and reactogenicity and encouraging immunogenicity in children and infants residing in a malaria-endemic area. The levels of functional GIA observed in RH5-vaccinated infants are the highest reported to date following human vaccination. These data support onward clinical development of RH5-based blood-stage vaccines to protect against clinical malaria in young African infants.
Funding: Medical Research Council, London, UK
Phase 1 Study of Two Merozoite Surface Protein 1 (MSP1(42)) Vaccines for Plasmodium falciparum Malaria
OBJECTIVES: To assess the safety and immunogenicity of two vaccines, MSP1(42)-FVO/Alhydrogel and MSP1(42)-3D7/Alhydrogel, targeting blood-stage Plasmodium falciparum parasites. DESIGN: A Phase 1 open-label, dose-escalating study. SETTING: Quintiles Phase 1 Services, Lenexa, Kansas between July 2004 and November 2005. PARTICIPANTS: Sixty healthy malaria-naïve volunteers 18–48 y of age. INTERVENTIONS: The C-terminal 42-kDa region of merozoite surface protein 1 (MSP1(42)) corresponding to the two allelic forms present in FVO and 3D7 P. falciparum lines were expressed in Escherichia coli, refolded, purified, and formulated on Alhydrogel (aluminum hydroxide). For each vaccine, volunteers in each of three dose cohorts (5, 20, and 80 μg) were vaccinated at 0, 28, and 180 d. Volunteers were followed for 1 y. OUTCOME MEASURES: The safety of MSP1(42)-FVO/Alhydrogel and MSP1(42)-3D7/Alhydrogel was assessed. The antibody response to each vaccine was measured by reactivity to homologous and heterologous MSP1(42), MSP1(19), and MSP1(33) recombinant proteins and recognition of FVO and 3D7 parasites. RESULTS: Anti-MSP1(42) antibodies were detected by ELISA in 20/27 (74%) and 22/27 (81%) volunteers receiving three vaccinations of MSP1(42)-FVO/Alhydrogel or MSP1(42)-3D7/Alhydrogel, respectively. Regardless of the vaccine, the antibodies were cross-reactive to both MSP1(42)-FVO and MSP1(42)-3D7 proteins. The majority of the antibody response targeted the C-terminal 19-kDa domain of MSP1(42), although low-level antibodies to the N-terminal 33-kDa domain of MSP1(42) were also detected. Immunofluorescence microscopy of sera from the volunteers demonstrated reactivity with both FVO and 3D7 P. falciparum schizonts and free merozoites. Minimal in vitro growth inhibition of FVO or 3D7 parasites by purified IgG from the sera of the vaccinees was observed. CONCLUSIONS: The MSP1(42)/Alhydrogel vaccines were safe and well tolerated but not sufficiently immunogenic to generate a biologic effect in vitro. Addition of immunostimulants to the Alhydrogel formulation to elicit higher vaccine-induced responses in humans may be required for an effective vaccine
Preclinical development of a stabilized RH5 virus-like particle vaccine that induces improved antimalarial antibodies
Plasmodium falciparum reticulocyte-binding protein homolog 5 (RH5) is a leading blood-stage malaria vaccine antigen target, currently in a phase 2b clinical trial as a full-length soluble protein/adjuvant vaccine candidate called RH5.1/Matrix-M. We identify that disordered regions of the full-length RH5 molecule induce non-growth inhibitory antibodies in human vaccinees and that a re-engineered and stabilized immunogen (including just the alpha-helical core of RH5) induces a qualitatively superior growth inhibitory antibody response in rats vaccinated with this protein formulated in Matrix-M adjuvant. In parallel, bioconjugation of this immunogen, termed "RH5.2," to hepatitis B surface antigen virus-like particles (VLPs) using the "plug-and-display" SpyTag-SpyCatcher platform technology also enables superior quantitative antibody immunogenicity over soluble protein/adjuvant in vaccinated mice and rats. These studies identify a blood-stage malaria vaccine candidate that may improve upon the current leading soluble protein vaccine candidate RH5.1/Matrix-M. The RH5.2-VLP/Matrix-M vaccine candidate is now under evaluation in phase 1a/b clinical trials
Effect of red blood cell variants on childhood malaria in Mali: a prospective cohort study
Red blood cell (RBC) variants protect African children from severe Plasmodium falciparum malaria. Their individual and interactive impacts on mild disease and parasite density, and their modification by age-dependent immunity, are poorly understood
Blood-stage malaria vaccine candidate RH5.1/Matrix-M in healthy Tanzanian adults and children; an open-label, non-randomised, first-in-human, single-centre, phase 1b trial
Background: A blood-stage Plasmodium falciparum malaria vaccine would provide a second line of defence to complement partially effective or waning immunity conferred by the approved pre-erythrocytic vaccines. RH5.1 is a soluble protein vaccine candidate for blood-stage P falciparum, formulated with Matrix-M adjuvant to assess safety and immunogenicity in a malaria-endemic adult and paediatric population for the first time.
Methods: We did a non-randomised, phase 1b, single-centre, dose-escalation, age de-escalation, first-in-human trial of RH5.1/Matrix-M in Bagamoyo, Tanzania. We recruited healthy adults (aged 18–45 years) and children (aged 5–17 months) to receive the RH5.1/Matrix-M vaccine candidate in the following three-dose regimens: 10 μg RH5.1 at 0, 1, and 2 months (Adults 10M), and the higher dose of 50 μg RH5.1 at 0 and 1 month and 10 μg RH5.1 at 6 months (delayed-fractional third dose regimen; Adults DFx). Children received either 10 μg RH5.1 at 0, 1, and 2 months (Children 10M) or 10 μg RH5.1 at 0, 1, and 6 months (delayed third dose regimen; Children 10D), and were recruited in parallel, followed by children who received the dose-escalation regimen (Children DFx) and children with higher malaria pre-exposure who also received the dose-escalation regimen (High Children DFx). All RH5.1 doses were formulated with 50 μg Matrix-M adjuvant. Primary outcomes for vaccine safety were solicited and unsolicited adverse events after each vaccination, along with any serious adverse events during the study period. The secondary outcome measures for immunogenicity were the concentration and avidity of anti-RH5.1 serum IgG antibodies and their percentage growth inhibition activity (GIA) in vitro, as well as cellular immunogenicity to RH5.1. All participants receiving at least one dose of vaccine were included in the primary analyses. This trial is registered at ClinicalTrials.gov, NCT04318002, and is now complete.
Findings: Between Jan 25, 2021, and April 15, 2021, we recruited 12 adults (six [50%] in the Adults 10M group and six [50%] in the Adults DFx group) and 48 children (12 each in the Children 10M, Children 10D, Children DFx, and High Children DFx groups). 57 (95%) of 60 participants completed the vaccination series and 55 (92%) completed 22 months of follow-up following the third vaccination. Vaccinations were well-tolerated across both age groups. There were five serious adverse events involving four child participants during the trial, none of which were deemed related to vaccination. RH5-specific T cell and serum IgG antibody responses were induced by vaccination and purified total IgG showed in vitro GIA against P falciparum. We found similar functional quality (ie, GIA per μg RH5-specific IgG) across all age groups and dosing regimens at 14 days after the final vaccination; the concentration of RH5.1-specific polyclonal IgG required to give 50% GIA was 14·3 μg/mL (95% CI 13·4–15·2). 11 children were vaccinated with the delayed third dose regimen and showed the highest median anti-RH5 serum IgG concentration 14 days following the third vaccination (723 μg/mL [IQR 511–1000]), resulting in all 11 who received the full series showing greater than 60% GIA following dilution of total IgG to 2·5 mg/mL (median 88% [IQR 81–94]).
Interpretation: The RH5.1/Matrix-M vaccine candidate shows an acceptable safety and reactogenicity profile in both adults and 5–17-month-old children residing in a malaria-endemic area, with all children in the delayed third dose regimen reaching a level of GIA previously associated with protective outcome against blood-stage P falciparum challenge in non-human primates. These data support onward efficacy assessment of this vaccine candidate against clinical malaria in young African children.
Funding: The European and Developing Countries Clinical Trials Partnership; the UK Medical Research Council; the UK Department for International Development; the National Institute for Health and Care Research Oxford Biomedical Research Centre; the Division of Intramural Research, National Institute of Allergy and Infectious Diseases; the US Agency for International Development; and the Wellcome Trust
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