Increased epidermal thickness and abnormal epidermal differentiation in keloid scars

Background: The pathogenesis underlying keloid formation is still poorly understood. Research has focused mostly on dermal abnormalities, while the epidermis has not yet been studied. Objectives: To identify differences within the epidermis of mature keloid scars compared with normal skin and mature normotrophic and hypertrophic scars. Methods: Rete ridge formation and epidermal thickness were evaluated in tissue sections. Epidermal proliferation was assessed using immunohistochemistry (Ki67, keratins 6, 16 and 17) and with an in vitro proliferation assay. Epidermal differentiation was evaluated using immunohistochemistry (keratin 10, involucrin, loricrin, filaggrin, SPRR2, SKALP), reverse-transcriptase polymerase chain reaction (involucrin) and transmission electron microscopy (stratum corneum). Results: All scars showed flattening of the epidermis. A trend of increasing epidermal thickness correlating to increasing scar abnormality was observed when comparing normal skin, normotrophic scars, hypertrophic scars and keloids. No difference in epidermal proliferation was observed. Only the early differentiation marker involucrin showed abnormal expression in scars. Involucrin was restricted to the granular layer in healthy skin, but showed panepidermal expression in keloids. Normotrophic scars expressed involucrin in the granular and upper spinous layers, while hypertrophic scars resembled normotrophic scars or keloids. Abnormal differentiation was associated with ultrastructural disorganization of the stratum corneum in keloids compared with normal skin. Conclusions: Keloids showed increased epidermal thickness compared with normal skin and normotrophic and hypertrophic scars. This was not due to hyperproliferation, but possibly caused by abnormal early terminal differentiation, which affects stratum corneum formation. Our findings indicate that the epidermis is associated with keloid pathogenesis and identify involucrin as a potential diagnostic marker for abnormal scarring

Using Intervention Mapping to develop a programme to prevent sexually transmittable infections, including HIV, among heterosexual migrant men

<p>Abstract</p> <p>Background</p> <p>There is little experience with carefully developed interventions in the HIV/STI prevention field aimed at adult heterosexual target groups in the Netherlands. The ability to apply intervention development protocols, like Intervention Mapping, in daily practice outside of academia, is a matter of concern. An urgent need also exists for interventions aimed at the prevention of STI in migrant populations in the Netherlands. This article describes the theory and evidence based development of HIV/STI prevention interventions by the Municipal Public Health Service Rotterdam Area (MPHS), the Netherlands, for heterosexual migrant men with Surinamese, Dutch-Caribbean, Cape Verdean, Turkish and Moroccan backgrounds.</p> <p>Methods</p> <p>First a needs assessment was carried out. Then, a literature review was done, key figures were interviewed and seven group discussions were held. Subsequently, the results were translated into specific objectives ("change objectives") and used in intervention development for two subgroups: men with an Afro-Caribbean background and unmarried men with a Turkish and Moroccan background. A matrix of change objectives was made for each subgroup and suitable theoretical methods and practical strategies were selected. Culturally-tailored interventions were designed and were pre-tested among the target groups.</p> <p>Results</p> <p>This development process resulted in two interventions for specific subgroups that were appreciated by both the target groups and the migrant prevention workers. The project took place in collaboration with a university center, which provided an opportunity to get expert advice at every step of the Intervention Mapping process. At relevant points of the development process, migrant health educators and target group members provided advice and feedback on the draft intervention materials.</p> <p>Conclusion</p> <p>This intervention development project indicates that careful well-informed intervention development using Intervention Mapping is feasible in the daily practice of the MPHS, provided that sufficient time and expertise on this approach is available. Further research should test the effectiveness of these interventions.</p

Cattle Mammary Bioreactor Generated by a Novel Procedure of Transgenic Cloning for Large-Scale Production of Functional Human Lactoferrin

Large-scale production of biopharmaceuticals by current bioreactor techniques is limited by low transgenic efficiency and low expression of foreign proteins. In general, a bacterial artificial chromosome (BAC) harboring most regulatory elements is capable of overcoming the limitations, but transferring BAC into donor cells is difficult. We describe here the use of cattle mammary bioreactor to produce functional recombinant human lactoferrin (rhLF) by a novel procedure of transgenic cloning, which employs microinjection to generate transgenic somatic cells as donor cells. Bovine fibroblast cells were co-microinjected for the first time with a 150-kb BAC carrying the human lactoferrin gene and a marker gene. The resulting transfection efficiency of up to 15.79×10−2 percent was notably higher than that of electroporation and lipofection. Following somatic cell nuclear transfer, we obtained two transgenic cows that secreted rhLF at high levels, 2.5 g/l and 3.4 g/l, respectively. The rhLF had a similar pattern of glycosylation and proteolytic susceptibility as the natural human counterpart. Biochemical analysis revealed that the iron-binding and releasing properties of rhLF were identical to that of native hLF. Importantly, an antibacterial experiment further demonstrated that rhLF was functional. Our results indicate that co-microinjection with a BAC and a marker gene into donor cells for somatic cell cloning indeed improves transgenic efficiency. Moreover, the cattle mammary bioreactors generated with this novel procedure produce functional rhLF on an industrial scale

Order-of-magnitude speedup for steady states and traveling waves via Stokes preconditioning in Channelflow and Openpipeflow

Steady states and traveling waves play a fundamental role in understanding hydrodynamic problems. Even when unstable, these states provide the bifurcation-theoretic explanation for the origin of the observed states. In turbulent wall-bounded shear flows, these states have been hypothesized to be saddle points organizing the trajectories within a chaotic attractor. These states must be computed with Newton's method or one of its generalizations, since time-integration cannot converge to unstable equilibria. The bottleneck is the solution of linear systems involving the Jacobian of the Navier-Stokes or Boussinesq equations. Originally such computations were carried out by constructing and directly inverting the Jacobian, but this is unfeasible for the matrices arising from three-dimensional hydrodynamic configurations in large domains. A popular method is to seek states that are invariant under numerical time integration. Surprisingly, equilibria may also be found by seeking flows that are invariant under a single very large Backwards-Euler Forwards-Euler timestep. We show that this method, called Stokes preconditioning, is 10 to 50 times faster at computing steady states in plane Couette flow and traveling waves in pipe flow. Moreover, it can be carried out using Channelflow (by Gibson) and Openpipeflow (by Willis) without any changes to these popular spectral codes. We explain the convergence rate as a function of the integration period and Reynolds number by computing the full spectra of the operators corresponding to the Jacobians of both methods.Comment: in Computational Modelling of Bifurcations and Instabilities in Fluid Dynamics, ed. Alexander Gelfgat (Springer, 2018

The OPTIMIST study: optimisation of cost effectiveness through individualised FSH stimulation dosages for IVF treatment. A randomised controlled trial

Contains fulltext : 109739.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Costs of in vitro fertilisation (IVF) are high, which is partly due to the use of follicle stimulating hormone (FSH). FSH is usually administered in a standard dose. However, due to differences in ovarian reserve between women, ovarian response also differs with potential negative consequences on pregnancy rates. A Markov decision-analytic model showed that FSH dose individualisation according to ovarian reserve is likely to be cost-effective in women who are eligible for IVF. However, this has never been confirmed in a large randomised controlled trial (RCT). The aim of the present study is to assess whether an individualised FSH dose regime based on an ovarian reserve test (ORT) is more cost-effective than a standard dose regime. METHODS/DESIGN: Multicentre RCT in subfertile women indicated for a first IVF or intracytoplasmic sperm injection cycle, who are aged < 44 years, have a regular menstrual cycle and no major abnormalities at transvaginal sonography. Women with polycystic ovary syndrome, endocrine or metabolic abnormalities and women undergoing IVF with oocyte donation, will not be included. Ovarian reserve will be assessed by measuring the antral follicle count. Women with a predicted poor response or hyperresponse will be randomised for a standard versus an individualised FSH regime (150 IU/day, 225-450 IU/day and 100 IU/day, respectively). Participants will undergo a maximum of three stimulation cycles during maximally 18 months. The primary study outcome is the cumulative ongoing pregnancy rate resulting in live birth achieved within 18 months after randomisation. Secondary outcomes are parameters for ovarian response, multiple pregnancies, number of cycles needed per live birth, total IU of FSH per stimulation cycle, and costs. All data will be analysed according to the intention-to-treat principle. Cost-effectiveness analysis will be performed to assess whether the health and associated economic benefits of individualised treatment of subfertile women outweigh the additional costs of an ORT. DISCUSSION: The results of this study will be integrated into a decision model that compares cost-effectiveness of the three dose-adjustment strategies to a standard dose strategy. The study outcomes will provide scientific foundation for national and international guidelines. TRIAL REGISTRATION: NTR2657

In vivo quantification of photosensitizer fluorescence in the skin-fold observation chamber using dual-wavelength excitation and NIR imaging

A major challenge in biomedical optics is the accurate quantification of in vivo fluorescence images. Fluorescence imaging is often used to determine the pharmacokinetics of photosensitizers used for photodynamic therapy. Often, however, this type of imaging does not take into account differences in and changes to tissue volume and optical properties of the tissue under interrogation. To address this problem, a ratiometric quantification method was developed and applied to monitor photosensitizer meso-tetra (hydroxyphenyl) chlorin (mTHPC) pharmacokinetics in the rat skin-fold observation chamber. The method employs a combination of dual-wavelength excitation and dualwavelength detection. Excitation and detection wavelengths were selected in the NIR region. One excitation wavelength was chosen to be at the Q band of mTHPC, whereas the second excitation wavelength was close to its absorption minimum. Two fluorescence emission bands were used; one at the secondary fluorescence maximum of mTHPC centered on 720 nm, and one in a region of tissue autofluorescence. The first excitation wavelength was used to excite the mTHPC and autofluorescence and the second to excite only autofluorescence, so that this could be subtracted. Subsequently, the autofluorescence-corrected mTHPC image was divided by the autofluorescence signal to correct for variations in tissue optical properties. This correction algorithm in principle results in a linear relation between the corrected fluorescence and photosensitizer concentration. The limitations of the presented method and comparison with previously published and validated techniques are discussed

Hepatitis B screening in the Turkish-Dutch population in Rotterdam, the Netherlands; qualitative assessment of socio-cultural determinants

Background. Hepatitis B is an important health problem in the Turkish community in the Netherlands. Increased voluntary screening is necessary in this community, to detect individuals eligible for treatment and to prevent further transmission of the disease. Methods. We investigated socio-cultural determinants associated with hepatitis B screening in male and female, first and second generation Turkish migrants, by means of Focus Group Discussions. Results. Socio-cultural themes related to hepatitis B screening were identified; these were social norm, social support, sensitivity regarding sexuality, reputation, responsiveness to authority, religious responsibility, cleanliness and religious doctrine regarding health and disease, and the perceived efficacy of Dutch health care services. Motivating factors were the (religious) responsibility for one's health, the perceived obligation when being invited for screening, and social support to get tested for hepatitis B. Perceived barriers were the association of hepatitis B screening with STDs or sexual activity, the perception of low control over one's health, and the perceived low efficacy of the Dutch health care services. Reputation could act as either a motivator or barrier. Conclusion. This study identified relevant socio-cultural themes related to hepatitis B screening, which may serve to customize interventions aimed at the promotion of voluntary hepatitis B screening in the Turkish-Dutch population in the Netherlands

Induction of Remission is Difficult due to Frequent Relapse during Tapering Steroids in Korean Patients with Polymyalgia Rheumatica

Polymyalgia rheumatica is an inflammatory disease affecting elderly and involving the shoulder and pelvic girdles. No epidemiological study of polymyalgia rheumatica was conducted in Korea. We retrospectively evaluated patients with polymyalgia rheumatica followed up at the rheumatology clinics of 10 tertiary hospitals. In total 51 patients, 36 patients (70.6%) were female. Age at disease onset was 67.4 yr. Twenty-three patients (45.1%) developed polymyalgia rheumatica in winter. Shoulder girdle ache was observed in 45 patients (90%) and elevated erythrocyte sedimentation rate (> 40 mm/h) in 49 patients (96.1%). Initial steroid dose was 23.3 mg/d prednisolone equivalent. Time to normal erythrocyte sedimentation rate was 4.1 months. Only 8 patients (15.7%) achieved remission. Among 41 patients followed up, 28 patients (68.3%) had flare at least once. Number of flares was 1.5 ± 1.6. The frequency of flare was significantly lower in patients with remission (P = 0.02). In Korea, polymyalgia rheumatica commonly develops during winter. Initial response to steroid is fairly good, but the prognosis is not benign because remission is rare with frequent relapse requiring long-term steroid treatment