247 research outputs found
Factors affecting the immunogenicity of the live attenuated influenza vaccine produced in continuous cell line
The biological basis for the restricted immunogenicity of some live attenuated influenza vaccine strains generated on the backbone of the cold adapted (ca) A/Singapore/1/1957/ca (H2N2) influenza A virus master strain and produced in the Vero cells was investigated. According to our previous results the vaccine candidate made from A/Hong Kong/1035/1998 (H1N1) Vero-derived virus did not provoke a measurable antibody titers following the intranasal immunization of humans. We report here that the hemagglutinin (HA) of A/Hong Kong/1035/1998 virus contained the mutation 10Ile→Val in the HA2 subunit, that increased the pH threshold of HA conformational change (pH of activation) by 0.3 pH units and therefore might be responsible for the lack of immune response in humans. Similar effect was shown for the reassortant made from the Vero-derived A/Switzerland/5389/1995 (H1N1) (5389wt) virus which had the HA2 mutation 3Phe→Leu leading to the lack of immune response in mice. Another factor compromising the immunogenicity of a vaccine candidate is the incompatibility of epidemic virus HA with the M gene of the master strain. In mice the 6/2 A/Switzerland/5389/1995 reassortant induced antibodies that were directed predominantly to the HA2 subunit and were detectable by ELISA but not by a hemagglutination inhibition (HAI) test. In contrast, the 5/3 reassortant, bearing the HA, neuraminidase (NA), and M genes from the epidemic virus induced an equivalent amount of antibodies against the HA1 and HA2 subunits detected by HAI and ELISA. By comparing the sensitivity of the viruses to amantadine, we showed that the M2 ion channel of the master strain had lower activity than that of the A/Switzerland/5389/1995. These data suggest that M2 of the master strain was not sufficiently active to keep the pH of the transGolgi network high enough to prevent the conformational change of the acid sensitive HA to the low pH form. Overall, the adaptation mutations in the HA of the vaccine candidate that increase the pH of HA activation as well as the incompatibility of HA and M genes must be taken into consideration when constructing the reassortant strains for the live attenuated vaccine.The biological basis for the restricted immunogenicity of some live attenuated influenza vaccine strains generated on the backbone of the cold adapted (ca) A/Singapore/1/1957/ca (H2N2) influenza A virus master strain and produced in the Vero cells was investigated. According to our previous results the vaccine candidate made from A/Hong Kong/1035/1998 (H1N1) Vero-derived virus did not provoke a measurable antibody titers following the intranasal immunization of humans. We report here that the hemagglutinin (HA) of A/Hong Kong/1035/1998 virus contained the mutation 10Ile→Val in the HA2 subunit, that increased the pH threshold of HA conformational change (pH of activation) by 0.3 pH units and therefore might be responsible for the lack of immune response in humans. Similar effect was shown for the reassortant made from the Vero-derived A/Switzerland/5389/1995 (H1N1) (5389wt) virus which had the HA2 mutation 3Phe→Leu leading to the lack of immune response in mice. Another factor compromising the immunogenicity of a vaccine candidate is the incompatibility of epidemic virus HA with the M gene of the master strain. In mice the 6/2 A/Switzerland/5389/1995 reassortant induced antibodies that were directed predominantly to the HA2 subunit and were detectable by ELISA but not by a hemagglutination inhibition (HAI) test. In contrast, the 5/3 reassortant, bearing the HA, neuraminidase (NA), and M genes from the epidemic virus induced an equivalent amount of antibodies against the HA1 and HA2 subunits detected by HAI and ELISA. By comparing the sensitivity of the viruses to amantadine, we showed that the M2 ion channel of the master strain had lower activity than that of the A/Switzerland/5389/1995. These data suggest that M2 of the master strain was not sufficiently active to keep the pH of the transGolgi network high enough to prevent the conformational change of the acid sensitive HA to the low pH form.Overall, the adaptation mutations in the HA of the vaccine candidate that increase the pH of HA activation as well as the incompatibility of HA and M genes must be taken into consideration when constructing the reassortant strains for the live attenuated vaccine
Evaluation of severity and therapy in children with atopic dermatitis
Atopic dennatitis (AD) is a conUllon chronically relapsing skin disorder affecting 9-20% of
those born after 1970 [Schultz Larsen 1993]. TI,e aetiology is still not entirely elucidated and
research is complicated by the multifactorial nature of the disease. Both genetical and
environmental factors are involved in the pathogenesis of AD. The prevalence of atopic
dennatitis seems to have increased along with astluna and allergic rhinitis during the past three
decades [Williams 1992, Schultz Larsen 1996]. Several studies from different countries
reported a two- to three-fold increase of the prevalence of AD over the past three decades.
However, the reasons for this evolution of atopic diseases still remain to be elucidated.
Furthennore, large, unexplained variations in prevalence have been reported between countries
and within countries [ISAAC 1998], suggesting a critical role for environmental thctors in
disease expression. Although some risk factors such as gender, parental smoking, and early
exposure to allergens Olouse dust mite, pets, cow's milk and solid food) have becn identified,
the role of other risk factors like socio-economic status, outdoor and indoor pollution and
infections in early life are still a matter of discussion.
Studies on the genetical and immunological background have provided new insights into the
mechanisms involved in atopic diseases. However, therapeutical practice has not yet changed.
Recently guidelines based on consensus have been established for the management of AD [Me
Henry 1995]. Emphasis is put on educating and infonning the patients. Although these and
other guidelines provide a good franlework for managing AD, the unpredictable course of the
disease with exacerbations and remissions may fiustrate both patients and physicians [przybilla
1994].
Patients with AD account for about 30% of demlatological consultations in general practice,
and dennatological consultations account for about 20% of all consultations in general practice
[Rook 1986]. However, little attention has been paid to AD in tenns of research. A Medline
literature search (title, abstract, and subject heading) from 1996 to May 1999 showed 8,986
publications related to astlUlla, but only 942 related to AD. This is surprising when the impact
of the two diseases is compared. In tenns of prevalence, AD is more conunon than asthma in
Y01Ulg children [Peat 1994, Burr 1989]; in tenns of economic resources, the direct fimUlcial cost in the care of a child with moderate to severe AD is substantially higher than for the average
child with asthma [Su 1997]; and in tenns of family impact - taking into account fmaneial
burden, familial/social impact, personal strain and mastery - even in mild AD, the impact on
fanlilies was found to be equivalent to that for children with insulin dependent diabetes mellitus
[Su 1997]. Consequently AD should not be perce
Reliability and validity of the vitiligo signs of activity score (VSAS)
Background The associations between disease activity and several clinical signs in vitiligo have been described, but a widely accepted and validated scoring system is lacking.
Objectives To validate the Vitiligo Signs of Activity Score (VSAS) for physicians.
Methods Three visible clinical signs were scored on 15 body locations: confetti-like depigmentation (c), Koebner phenomenon (k) and hypochromic areas/borders (h). The inter- and intrarater reliability of the global VSAS and VSAS subscores (c-VSAS, k-VSAS and h-VSAS) were tested by four and three raters (physicians), respectively. Construct validity and feasibility were evaluated.
Results The VSAS demonstrated good inter-rater reliability, with an intraclass correlation coefficient (ICC) of 0 center dot 87 in the first round and 0 center dot 90 in the second round. The intrarater reliability ICCs were all >= 0 center dot 86. The inter-rater reliabilities of the subscores were excellent for c-VSAS and fair for k-VSAS and h-VSAS (ICC 0 center dot 83, 0 center dot 51 and 0 center dot 53, respectively, in the first round). Evidence for construct validity was provided. The completion time by the raters (median 2 center dot 18 min per patient) improved during the second round (median 1 center dot 33 min per patient). A limitation of the study is the low number of patients, mainly of skin phototypes II-III, from a single tertiary centre.
Conclusions The VSAS appears to be a valid and reliable instrument to score visible clinical signs linked to disease activity in a standardized way.
What is already known about this topic?
Evidence exists for a possible link between several visible clinical signs in vitiligo and disease activity.
A widely accepted and validated scoring system to quantify these clinical signs is lacking.
What does this study add?
The Vitiligo Signs of Activity Score (VSAS) underwent preliminary validation and may assist quantification of visible clinical signs linked to disease activity in a standardized way in clinical practice and trials
Needle-free electronically controlled jet injection with corticosteroids in recalcitrant keloid scars:a retrospective study and patient survey
First-line treatment of keloids consists of intralesional needle injections with corticosteroids, but generally entails multiple painful sessions, resulting in variable clinical outcomes. Novel needle-free jet injectors may facilitate more effective and patient-friendly dermal drug delivery. Here, we evaluated the effectiveness, tolerability and patient satisfaction of intralesional triamcinolone-acetonide (TCA) treatment in recalcitrant keloids using an electronically controlled pneumatic injector (EPI). A retrospective study was conducted in recalcitrant keloid patients with a history of severe pain during needle injections who received three sessions of EPI + TCA. Outcome measures included Patient and Observer Scar Assessment Scale (POSAS), Global Aesthetic Improvement Scale (GAIS), treatment-related pain (NRS), adverse effects, and patient satisfaction (survey). Ten patients with in total 283 keloids were included. The POSAS score significantly improved at follow-up and GAIS was reported as ‘(very) improved’ for all patients. EPI + TCA was well-tolerated with a significantly lower NRS pain score compared to needle + TCA (pilot treatment). Only minor adverse effects occurred, and 90% of patients preferred EPI over needle treatment. EPI + TCA is an effective and tolerable treatment for patients with recalcitrant keloids. The minimal treatment-related pain and high patient satisfaction makes it a promising treatment for patients with needle-phobia and/or severe pain during needle injections
PHP58 A Mediação De Conflitos Na Ação Fiscalizatoria Do Setor De Saúde Suplementar Brasileiro
Background Punch grafting is a simple and frequently used technique for the treatment of stable vitiligo, resistant to medical therapy. However, studies reporting long-term results are exceptional. Objectives To evaluate the long-term results of 2-mm punch grafting in patients with vitiligo vulgaris and segmental vitiligo. Methods We studied a prospective cohort study involving 61 patients (25 male, 36 female) with vitiligo vulgaris and nine patients (all male) with segmental vitiligo who underwent 2-mm punch grafting more than 3 years ago. The main outcome measure was the degree of repigmentation of a single transplanted lesion as measured with a digital image analysis system with a mean follow-up of 5 2 years. Results In patients with vitiligo vulgaris, 17 lesions (28%) showed excellent, 14 lesions (23%) showed good, 14 lesions (23%) showed fair and 16 lesions (26%) showed poor repigmentation. In patients with segmental vitiligo, seven of nine lesions (78%) showed excellent repigmentation. A cobblestone-like effect was observed in 19 of 70 patients (27%). Disease activity after punch grafting was reported in 94% of patients with poor repigmentation but in only 18% of patients with excellent repigmentation (chi(2) test, P <0 0005). Patients who reported disease activity after transplantation had a lower mean repigmentation than those who did not report disease activity (77% vs. 39%, P <0 05). Conclusions Two-millimetre punch grafting in vitiligo is an effective surgical procedure with long-lasting effect. To prevent a cobblestone-like effect, we advise the use of smaller grafts (1-1.2 mm). Disease activity after grafting, localization and type of vitiligo, prior ultraviolet B treatment and a Koebnerized donor site influence the long-term outcome of punch grafting and should be taken into account in the selection of patients eligible for this treatment
Diagnostic accuracy of confocal microscopy imaging vs. punch biopsy for diagnosing and subtyping basal cell carcinoma
Background: In vivo reflectance confocal microscopy (RCM) is a promising non-invasive skin imaging technique that could facilitate early diagnosis of basal cell carcinoma (BCC) instead of routine punch biopsies. However, the clinical value and utility of RCM vs. a punch biopsy in diagnosing and subtyping BCC is unknown. Objective: To assess diagnostic accuracy of RCM vs. punch biopsy for diagnosing and subtyping clinically suspected primary BCC. Methods: A prospective, consecutive cohort of 100 patients with clinically suspected BCC were included at two tertiary hospitals in Amsterdam, the Netherlands, between 3 February 2015 and 2 October 2015. Patients were randomized between two test-treatment pathways: diagnosing and subtyping using RCM imaging followed by direct surgical excision (RCM one-stop-shop) or planned excision based upon the histological diagnosis and subtype of punch biopsy (standard care). The primary outcome was the agreement between the index tests (RCM vs. punch biopsy) and reference standard (excision specimen) in correctly diagnosing BCC. The secondary outcome was the agreement between the index tests and reference standard in correctly identifying the most aggressive BCC subtypes. Results: Sensitivity to detect BCC was similar for RCM and punch biopsy (100% vs. 93.94%), but a punch biopsy was more specific than RCM (79% vs. 38%). RCM expert evaluation for diagnosing BCC had a sensitivity of 100% and a specificity of 75%. The agreement between RCM and excision specimen in identifying the most aggressive BCC subtype ranged from 50% to 85% vs. 77% by a punch biopsy. Conclusion: Reflectance confocal microscopy and punch biopsy have comparable diagnostic accuracy to diagnose and subtype BCC depending on RCM experience. Although experienced RCM users could accurately diagnose BCC at a distance, we found an important difference in subtyping BCC. Future RCM studies need to focus on diagnostic accuracy, reliability and specific criteria to improve BCC subtype differentiation
Validation of a Patient Global Assessment for extent, severity and impact to define the severity strata for the Self Assessment Vitiligo Extent Score (SA-VES)
Background: The Self Assessment Vitiligo Extent Score (SA‐VES) is a validated, patient‐reported outcome measure to assess the body surface area affected with vitiligo. Information on how to translate the obtained score into extent, severity and impact strata (mild–moderate–severe) is still lacking. Stratification is helpful to define inclusion criteria for trials, enables comparison and pooling of trial results and can be used for epidemiological research.
Objectives: The aim was to develop extent, severity and impact strata for the SA‐VES based on validated anchor‐based questions.
Methods: In total, 315 patients with vitiligo (non‐segmental; age ≥ 16) recruited at the Ghent University Hospital (Belgium) completed a questionnaire that was conducted in cooperation with the Dutch Society for vitiligo patients to ensure content validity. First three anchor questions included in the questionnaire [Patient Global Assessment (PtGA) for vitiligo extent, severity and impact] were assessed for content validity, construct validity and intrarater reliability. Subsequently, the PtGAs were used to stratify the SA‐VES based on ROC analysis.
Results: For all PtGAs (PtGA extent, PtGA severity, PtGA impact), at least 75% of hypotheses evaluated for construct validity were confirmed. Intrarater reliability of all PtGAs was good to excellent (ICCs PtGA extent: 0.623; PtGA severity: 0.828; PtGA impact: 0.851). The optimal cut‐off values of the SA‐VES between the three global categories (mild/limited – moderate – severe/extensive) were 1.05% and 6.45% based on PtGA extent, 2.07% and 4.8% based on PtGA severity and 2% and 3.35% based on PtGA impact.
Conclusion: This study provides the first guide for the interpretation of the numerical output obtained by the SA‐VES (vitiligo extent) and enables the translation into a global vitiligo grading for extent, severity and impact. As patients’ interpretation of vitiligo extent, severity and impact may vary amongst patients worldwide, future international studies will be required
Safety and efficacy of fluticasone propionate in the topical treatment of skin diseases
Fluticasone propionate - the first carbothioate corticosteroid - has been classified as a potent anti-inflammatory drug for dermatological use. It is available as 0.05% cream and 0.005% ointment formulations for the acute and maintenance treatment of patients with dermatological disorders such as atopic dermatitis, psoriasis and vitiligo. This glucocorticoid is characterized by high lipophilicity, high glucocorticoid receptor binding and activation, and a rapid metabolic turnover in skin. Although skin blanching following fluticasone propionate exceeds that of corticosteroids of medium strength, several clinical trials demonstrate a low potential for cutaneous and systemic side-effects, even in difficult-to-treat areas like the face, the eyelids and intertriginous areas. Even among paediatric patients with atopic dermatitis, fluticasone propionate proved to be safe and effective. These pharmacological and clinical properties are reflected by the high therapeutic index of this glucocorticoid
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