Our objective was to investigate the effect of performing primary drying at product temperatures below and above Tg′ (glass transition temperature of the freeze-concentrated phase) on the long-term ...stability of lyophilized proteins. Two protective media differing in the nature of the bulking agent used (amorphous or crystalline) were selected. Several lyophilization cycles were performed by using various combinations of shelf temperature and chamber pressure to obtain different values of product temperature during primary drying. The antigenic activity of the proteins was measured after lyophilization and after 6 months of storage at 4°C and 25°C. After 6 months of storage and regardless of the protective medium, the losses of antigenic activity of both toxins increased from 0% when primary drying was performed at a product temperature lower than Tg′ and to 25% when the product temperature was higher than Tg′. The use of partially crystalline systems makes it possible to withstand high primary drying temperatures (above Tg′). However, the shelf life of lyophilized proteins may be decreased when the amorphous phase including the protein and the stabilizing molecule changes to the viscous state.
•Although the high rate of intimate partner violence in Haiti, its association with PTSD is unexplored.•Results showed that participants with experience of IPV present more symptoms of PTSD.•This ...study shows that intimate partner violence is a strong predictor of PTSD symptoms.•Emotion dysregulation amplified PTSD symptoms among those with experience of IPV.
Although the high prevalence of intimate partner violence (IPV) in Haiti is well-documented, its association with post-traumatic stress disorder (PTSD) symptoms among adolescents and young adults remains unexplored. Using a representative sample of adolescents and young adults from rural and urban areas across the 10 geographical regions of Haiti, this study investigates the association between IPV and PTSD symptoms. It explores the role of social support, emotion regulation, other traumatic events, and sociodemographic factors. The sample consisted of 3,586 participants, of whom 43.21 % (1,538) reported being in a dating relationship in the past year (56.04 % women). Overall, 25.53 % of the participants were categorized as having probable PTSD. Results showed that participants who experienced at least one episode of IPV victimization presented a higher prevalence of PTSD (32.28 %) compared to those who did not have any experience (16.29 %), χ2 (1) = 44.83, p < .001. The logistic regression model showed that emotional IPV, sexual IPV, traumatic life events, emotional dysregulation, and social support were associated with PTSD symptoms. This study highlights a strong association between IPV and PTSD symptoms, as well as factors that can contribute to the development and implementation of prevention and intervention programs among adolescents and young adults in Haiti.
The NS2B-NS3 serine protease of Saint Louis Encephalitis virus (SLEV), a potential target for antiviral drug design, has been over-expressed as a recombinant His-tag protein in
Escherichia coli for ...future structural determination. The production process resulted in a soluble protease with co-purification of DnaK, a bacterial molecular chaperone already described in
E. coli protein expression. Two approaches were tested to remove this specific contaminant. The fusion protein bound to the purification resin was washed with MgATP plus soluble denatured
E. coli proteins before elution, but this method proved to be poorly efficient due to a substantial loss of the targeted recombinant protease. After the immobilized metal affinity chromatography step, the use of gel permeation chromatography with addition of arginine in the mobile phase led to effective separation of the native viral protease from the DnaK aggregates. By this way, SLEV ΔNS2B-NS3pro protease was purified as a functional protein with a purity greater than 90% suitable for crystallization attempts.
Objectif : Nous explorons ici le travail de santé des patients vivant avec le virus de l’hépatite C (VHC) dans les différents temps de la vie avec la maladie et ses dilemmes (dépistage, annonce du ...diagnostic, traitements, particularités du rapport aux médecins et services de santé, activités associatives). Méthodes : Notre recherche, réalisée dans le cadre d’une convention avec l’Agence nationale de recherche sur le sida et les hépatites virales, s’appuie sur l’analyse de 20 entretiens individuels et de réunions de groupes de parole de patients dans un cadre associatif. Résultats : Le travail de santé réalisé par les patients vivant avec le VHC recouvre des activités de soin (au sens du care et du cure) de soi, de recherche d’informations sur la pathologie et ses traitements, des auto-prescriptions réglant le style et l’hygiène de vie. Il implique aussi la coopération avec les soignants, la réorganisation du travail demandé par la prescription médicale pour l’ajuster aux exigences et contraintes des autres sphères d’activités comme aux désirs et aspirations du sujet. Ce travail comporte nombre d’arbitrages et de régulations. Nous avons donc rejoint en partie les travaux de Strauss et son équipe (1984) qui abordent la gestion de la maladie chronique dans la vie quotidienne comme un travail, donc en termes non seulement de perceptions, de sens, mais aussi d’actions. Toutefois, nous montrons que ce travail de santé se développe dans tous les domaines de vie. Conclusion : Ces régulations permettent de prévenir la menace de précarisation sanitaire et sociale. Elles cherchent à accroître le pouvoir d’agir du sujet sur lui-même et sur son environnement.
We report herein the study of the cleavage fragments generated by autoproteolysis of the St. Louis encephalitis virus recombinant protease. The cleavage sites leading to truncated forms were ...identified by microsequencing, which revealed an unexpected altered specificity of the recombinant proteinase towards unusual sequences.
We investigated the treatment burden of patients living with hepatitis during various phases of the disease (screening, announcement of the diagnosis, treatments, specificities of the relationship ...with physicians and health services, activities within an association).
This research, conducted with the sponsorship of ANRS (National AIDS Research Agency), was based on the analysis of 20 individual interviews and group meetings with patients belonging to associations.
The treatment burden of patients living with HCV included health care activities (both care and cure), the search for information about the disease and its treatments, and self-prescriptions which determine the patient's lifestyle and hygiene. It also concerned cooperation with health care workers, job adjustm.ent as required by the medical prescription to adjust the job to the requirements and constraints of the other areas of activity and to the patient's desires and aspirations, based on numerous arbitrations and regulations. This work therefore resembled that conducted by Strauss and his team (1984) who considered the management of chronic illness in daily life to be a form of work; not only in terms of perceptions and meanings but also in terms of actions. However, we showed that this treatment burden affects all aspects of life.
These regulations help to prevent the risk of health and social exclusion and are designed to increase the patient's ability to act on themselves and their environment.
The development of stable freeze-dried proteins requires maintaining the physical and biological integrity of the protein as well as increasing the efficiency of the manufacturing process. Our ...objective was to study the effects of various excipients on both the physical characterisation and the dried and liquid stability of two proteins. Thermo-physical properties of 13 formulations were determined using both differential scanning calorimetry and freeze–drying microscopy. The antigenic activity was evaluated immediately after freeze–drying and after subsequent storage in both dried and liquid state. From the comparison between glass transition (
T′
g) and collapse (
T
coll) temperatures, we concluded that the collapse temperature was a more relevant parameter than
T′
g for freeze–drying cycle development and optimisation. One crystalline formulation composed of 4% mannitol and 1% of sucrose protected efficiently both proteins during subsequent storage in dried state (6 months at 25
°C) and in liquid state (3 months at 4
°C after rehydration). However, the freeze–drying behaviour of this crystalline formulation remained difficult to predict and control. On the other hand, two amorphous formulations composed of 4% of maltodextrin and 0.02% of Tween 80, or 5% of BSA preserved antigenic activity during storage in dried state. The glassy character of these formulations as well as their high collapse temperature values (−9 and −12
°C, respectively) should allow simplification and shortening of freeze–drying process.
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