Addition of docetaxel to hormonal therapy in low- and high-burden metastatic hormone sensitive prostate cancer: long-term survival results from the STAMPEDE trial

BACKGROUND

STAMPEDE has previously reported that the use of upfront docetaxel improved overall survival (OS) for metastatic hormone naïve prostate cancer patients starting long-term androgen deprivation therapy. We report on long-term outcomes stratified by metastatic burden for M1 patients.

METHODS

We randomly allocated patients in 2 : 1 ratio to standard-of-care (SOC; control group) or SOC + docetaxel. Metastatic disease burden was categorised using retrospectively-collected baseline staging scans where available. Analysis used Cox regression models, adjusted for stratification factors, with emphasis on restricted mean survival time where hazards were non-proportional.

RESULTS

Between 05 October 2005 and 31 March 2013, 1086 M1 patients were randomised to receive SOC (n = 724) or SOC + docetaxel (n = 362). Metastatic burden was assessable for 830/1086 (76%) patients; 362 (44%) had low and 468 (56%) high metastatic burden. Median follow-up was 78.2 months. There were 494 deaths on SOC (41% more than the previous report). There was good evidence of benefit of docetaxel over SOC on OS (HR = 0.81, 95% CI 0.69-0.95, P = 0.009) with no evidence of heterogeneity of docetaxel effect between metastatic burden sub-groups (interaction P = 0.827). Analysis of other outcomes found evidence of benefit for docetaxel over SOC in failure-free survival (HR = 0.66, 95% CI 0.57-0.76, P < 0.001) and progression-free survival (HR = 0.69, 95% CI 0.59-0.81, P < 0.001) with no evidence of heterogeneity of docetaxel effect between metastatic burden sub-groups (interaction P > 0.5 in each case). There was no evidence that docetaxel resulted in late toxicity compared with SOC: after 1 year, G3-5 toxicity was reported for 28% SOC and 27% docetaxel (in patients still on follow-up at 1 year without prior progression).

CONCLUSIONS

The clinically significant benefit in survival for upfront docetaxel persists at longer follow-up, with no evidence that benefit differed by metastatic burden. We advocate that upfront docetaxel is considered for metastatic hormone naïve prostate cancer patients regardless of metastatic burden.

Effect of fibroblasts on epidermal regeneration

BACKGROUND

There is little information on specific interactions between dermal fibroblasts and epidermal keratinocytes. The use of engineered skin equivalents consisting of organotypic cocultures of keratinocytes and fibroblasts offers an attractive approach for such studies.

OBJECTIVES

To examine the role fibroblasts play in generation and maintenance of reconstructed epidermis.

METHODS

Human keratinocytes were seeded on collagen matrices populated with increasing numbers of fibroblasts and cultured for 2 weeks at the air-liquid interface.

RESULTS

In the absence of fibroblasts, stratified epidermis with only three or four viable cell layers was formed. In the presence of fibroblasts, keratinocyte proliferation was stimulated and epidermal morphology was improved. Epidermal morphogenesis was also markedly improved in epidermis generated in organotypic keratinocyte monocultures grown in medium derived from dermal equivalents or from organotypic keratinocyte-fibroblast cocultures. These observations clearly indicate the proliferation-stimulating activity of soluble factors released from fibroblasts. Under all experimental conditions, onset of keratinocyte differentiation was shown by the expression of keratin 10 in all suprabasal cell layers. With increasing numbers of fibroblasts incorporated into the collagen matrix, the expression of markers associated with keratinocyte activation, e.g. keratins 6, 16 and 17 and the cornified envelope precursor SKALP decreased, and involucrin localization shifted toward the granulosum layer. This fibroblast-mediated effect was even more pronounced when the fibroblasts were precultured in the collagen matrices for 1 week instead of overnight. The basement membrane proteins collagen VII and laminin 5 were present at the epithelial-matrix border. The expression of integrin alpha 6 beta 4 and of E-cadherin was comparable with that seen in native skin and was not significantly modulated by fibroblasts. Under all experimental conditions the expression of integrin subunits alpha 2, alpha 3 and beta 1 was upregulated, indicating keratinocyte activation.

CONCLUSIONS

Our results illustrate that numbers of fibroblasts in the collagen matrix and their functional state is a critical factor for establishment of normal epidermal morphogenesis.

Adding abiraterone or docetaxel to long-term hormone therapy for prostate cancer: directly randomised data from the STAMPEDE multi-arm, multi-stage platform protocol

Background

Adding abiraterone acetate with prednisolone (AAP) or docetaxel with prednisolone (DocP) to standard-of-care (SOC) each improved survival in systemic therapy for advanced or metastatic prostate cancer: evaluation of drug efficacy: a multi-arm multi-stage platform randomised controlled protocol recruiting patients with high-risk locally advanced or metastatic PCa starting long-term androgen deprivation therapy (ADT). The protocol provides the only direct, randomised comparative data of SOC + AAP versus SOC + DocP.

Method

Recruitment to SOC + DocP and SOC + AAP overlapped November 2011 to March 2013. SOC was long-term ADT or, for most non-metastatic cases, ADT for ≥2 years and RT to the primary tumour. Stratified randomisation allocated pts 2 : 1 : 2 to SOC; SOC + docetaxel 75 mg/m2 3-weekly×6 + prednisolone 10 mg daily; or SOC + abiraterone acetate 1000 mg + prednisolone 5 mg daily. AAP duration depended on stage and intent to give radical RT. The primary outcome measure was death from any cause. Analyses used Cox proportional hazards and flexible parametric models, adjusted for stratification factors. This was not a formally powered comparison. A hazard ratio (HR) <1 favours SOC + AAP, and HR > 1 favours SOC + DocP.

Results

A total of 566 consenting patients were contemporaneously randomised: 189 SOC + DocP and 377 SOC + AAP. The patients, balanced by allocated treatment were: 342 (60%) M1; 429 (76%) Gleason 8-10; 449 (79%) WHO performance status 0; median age 66 years and median PSA 56 ng/ml. With median follow-up 4 years, 149 deaths were reported. For overall survival, HR = 1.16 (95% CI 0.82-1.65); failure-free survival HR = 0.51 (95% CI 0.39-0.67); progression-free survival HR = 0.65 (95% CI 0.48-0.88); metastasis-free survival HR = 0.77 (95% CI 0.57-1.03); prostate cancer-specific survival HR = 1.02 (0.70-1.49); and symptomatic skeletal events HR = 0.83 (95% CI 0.55-1.25). In the safety population, the proportion reporting ≥1 grade 3, 4 or 5 adverse events ever was 36%, 13% and 1% SOC + DocP, and 40%, 7% and 1% SOC + AAP; prevalence 11% at 1 and 2 years on both arms. Relapse treatment patterns varied by arm.

Conclusions

This direct, randomised comparative analysis of two new treatment standards for hormone-naïve prostate cancer showed no evidence of a difference in overall or prostate cancer-specific survival, nor in other important outcomes such as symptomatic skeletal events. Worst toxicity grade over entire time on trial was similar but comprised different toxicities in line with the known properties of the drugs.

Trial registration

Clinicaltrials.gov: NCT00268476.

Molecular characterization and evolution of the SPRR family of keratinocyte differentiation markers encoding small proline-rich proteins

SPRR genes (formerly SPR) encode a novel class of polypeptides (small proline rich proteins) that are strongly induced during differentiation of human epidermal keratinocytes in vitro and in vivo. Recently we found that the N- and C-terminal domains of these proteins show strong sequence homology to loricrin and involucrin, suggesting that SPRR proteins constitute a new class of cornified envelope precursor proteins. Here we show that SPRR proteins are encoded by closely related members of a gene family, consisting of two genes of SPRR1, approximately seven genes for SPRR2, and a single gene for SPRR3. All SPRR genes are closely linked within a 300-kb DNA segment on human chromosome 1 band q21-q22, a region where the related loricrin and involucrin genes have also been mapped. The most characteristic feature of the SPRR gene family resides in the structure of the central segments of the encoded polypeptides that are built up from tandemly repeated units of either eight (SPRR1 and SPRR3) or nine (SPRR2) amino acids with the general consensus *K*PEP**. Sequencing data of the different members, together with their clustered chromosomal organization, strongly suggest that this gene family has evolved from a single progenitor gene by multiple intra- and intergenic duplications. Analysis of the different SPRR subfamilies reveals a gene-specific bias to either intra- or intergenic duplication. We propose that a process of homogenization has acted on the different members of one subfamily, whereas the different subfamilies appear to have diverged from each other, at the levels of both protein structure and gene regulation.

The small proline-rich proteins constitute a multigene family of differentially regulated cornified cell envelope precursor proteins

Loricrin, involucrin, small proline-rich protein (SPRR)1, SPRR2, and SPRR3 genes are located within a cluster of 1.5 Mbp on chromosome 1q21 and most likely evolved from a common ancestor. Monospecific polyclonal antibodies and cDNA probes were produced to investigate SPRR transcripts and proteins. SPRR expression was restricted to terminally differentiating squamous cells, preferentially located at the cell periphery, and immunoreactivity was greatly reduced in cells with a mature cornified cell envelope. Furthermore, detectable SPRR2 and SPRR3 levels were strongly increased in differentiating keratinocyte cultures after addition of LTB-2, a specific inhibitor of transglutaminases, suggesting that they are precursor proteins of the cornified cell envelope. In normal epidermis, SPRR1 was restricted to appendageal areas, SPRR2 was expressed coherently, and SPRR3 was completely absent. In the upper digestive tract, SPRR1 was expressed in sublingual and tongue epithelium, SPRR2 was mostly restricted to lingual papillae, and SPRR3 was abundant in oral and esophageal epithelium. In psoriatic epidermis, SPRR1 and SPRR2 were expressed at much higher levels than in normal epidermis. Addition of 10(-7) M retinoic acid to cultured differentiating keratinocytes significantly down-regulated the expression of SPRR2 and SPRR3 transcripts and slightly decreased that of SPRR1. Thus, SPRR1, SPRR2, and SPRR3 are differentially expressed in vivo and in vitro, suggesting that the SPRR multigene family evolved to serve as highly specialized cornified cell envelope precursor proteins in stratified epithelia.

Blood basophil numbers in chronic ordinary urticaria and healthy controls: diurnal variation, influence of loratadine and prednisolone and relationship to disease activity

BACKGROUND

The basopenia of chronic urticaria relates to histamine releasing autoantibodies in the serum of patients with autoimmune urticaria. This reduction in circulating basophils may be due to active recruitment into weals. If so, it might be expected that numbers in blood would be reduced when urticaria is active and increased after treatment. The primary aim of this study was to look at diurnal variation of basophil numbers in patients with chronic ordinary urticaria (not physical or vasculitic) in relation to disease activity and the effect of treatment with antihistamines and corticosteroids, and to compare the results with healthy controls. A secondary aim was to compare a standard manual counting method with automated basophil counts and to look at numbers of other circulating leucocytes that might be relevant to urticaria pathogenesis.

METHODS

Manual basophil counts using a toluidine blue stain and automated 5-part differentials (Coulter Gen. S) were performed at 4-hourly intervals from 08.00 to 20.00 in 10 healthy controls (six women, age 24 to 63 years) and seven chronic urticaria patients (five women, 24 to 50 years). All chronic urticaria patients had severe daily or almost daily urticaria. Only one of six chronic urticaria sera showed in vitro basophil histamine releasing activity. Counts were performed without treatment, after a week of taking loratadine 10 mg daily and after 3 days of adding prednisolone at 0.6 mg/kg/day (maximum 40 mg). Daily urticarial activity scores (UAS) were derived from weal numbers and itch, maximum 7.

RESULTS

There was no significant overall diurnal variation of basophil numbers in healthy controls or chronic urticaria patients. Mean (SE) manually counted basophil were higher in healthy controls than chronic urticaria (43.4/ microL (2.1) vs. 4.4 (0.8), P < 0.001). Basophil counts were reduced in healthy controls on steroids (19.2 (1.9), P < 0.001) but increased in chronic urticaria (8.9 (1.9), P < 0.001). Loratadine did not influence them. UAS fell on treatment (3.3 (0.4) baseline, 1.4 (0.5) on loratadine and 0.5 (0.2) on prednisolone with loratadine, P < 0.001). There was a negative linear correlation between basophil numbers and UAS in untreated chronic urticaria patients (P = 0.001, Spearman rank correlation). Manual and automated basophil counts showed poor agreement. Lymphocyte numbers were lower in chronic urticaria than healthy controls. Neutrophils increased whereas lymphocytes and eosinophils decreased in all subjects on prednisolone. They were unaffected by loratadine.

CONCLUSION

The results are consistent with the hypothesis that circulating basophils may be recruited from blood into urticarial weals during disease activity. Automated counts are not suitable for assessing basophil numbers in chronic urticaria. The relevance of reduced lymphocyte numbers in chronic urticaria needs to be explored.

Skin disease and socioeconomic conditions in rural Africa: Tanzania

BACKGROUND

Many skin diseases in developing countries are associated with socioeconomic factors. It is generally agreed that a public health approach to dermatology in this setting is particularly appropriate; but, there has been little epidemiologic research done to examine which particular socioeconomic factors are important determinants of the prevalence of skin disease. This is especially true in sub-Saharan Africa.

METHODS

A survey of two villages in Ngara district, North West Tanzania, involved 254 randomly selected households using a questionnaire, measurements of houses and water quality, and examination of the skin of 1114 household members.

RESULTS

Significant skin disease was encountered in 300 individuals (26.9%). Transmissible diseases comprised the bulk of skin disease (73.9%) with younger age groups being affected most. Socioeconomic conditions were poor, with low quality, crowded housing, low levels of literacy, unsatisfactory water sources, and few households with a regular cash income. Household density was significantly associated with transmissible skin disease. Other indicators of poverty (e.g., no regular cash income and illiteracy) did not correlate with the prevalence of skin disease.

CONCLUSIONS

Skin disease as highly prevalent in the villages surveyed, especially transmissible diseases in the younger age groups. Household density was the only socioeconomic factor significantly associated with skin disease. Reduction of household density is an attainable intervention that could reduce the prevalence of skin disease in rural African populations. Simple studies like this one should be the first step in community dermatology, assessing the burden of skin disease in communities and looking for particular factors with which public health interventions could effectively reduce the prevalence of skin disease.

The benefits of prescription information leaflets (1)

1. Prescription information leaflets (PILs) giving information about non-steroidal anti-inflammatory drugs (NSAIDs), beta-adrenoceptor antagonists and inhaled bronchodilators were evaluated in three small Hampshire towns, while a fourth, in which no leaflets were distributed, acted as a control. 2. Seven hundred and nineteen (82%) patients prescribed one of these medicines agreed to be interviewed in their homes, 1 to 2 weeks after the medicine had been prescribed. Four hundred and nineteen of them had received leaflets, while 300 received no written information. Two hundred and sixty patients received their leaflets from a pharmacist while 159 were given them by their general practitioner. 3. Patients who received leaflets were better informed about every item of knowledge tested, except for the name of the medicine. Awareness of the side effects showed the greatest improvement, but there was no evidence that these leaflets produced spurious side effects. 4. Much improved levels of satisfaction were recorded amongst patients who received leaflets, especially those for NSAIDs (P less than 0.001) and for beta-adrenoceptor antagonists (P less than 0.01). 5. Subsequently, three hundred and fifty-eight (77%) of the patients prescribed either a NSAID or a beta-adrenoceptor antagonist 1 year earlier responded to a postal questionnaire. The benefits in terms of knowledge and satisfaction were still apparent, although less marked than previously. Of the patients still taking beta-adrenoceptor antagonists 70% had retained their leaflets over the intervening 12 months. 6. Ninety-seven per cent of patients read their leaflet regardless of whether it was distributed by a general practitioner or pharmacist. However, those who obtained it from a pharmacist tended to be more knowledgeable and satisfied. 7. We conclude that patients welcome the idea of receiving PILs. They improve patients' knowledge of how to take their medicines correctly and their awareness of potential side effects. Importantly, patients who receive leaflets are more satisfied than those who do not. These overall benefits justify the use of leaflets on a routine basis.

Epidermal growth factor and keratinocyte growth factor differentially regulate epidermal migration, growth, and differentiation

Various growth factors such as epidermal growth factor and keratinocyte growth factor have been reported to promote wound closure and epidermal regeneration. In the present study epidermis reconstructed on de-epidermized dermis was used to investigate the effects of epidermal growth factor and keratinocyte growth factor on keratinocyte proliferation, migration and differentiation. Our results show that epidermal growth factor supplemented cultures share many of the features which are observed during regeneration of wounded epidermis: a thickening of the entire epidermis, an enhanced rate of proliferation and migration, and an increase in keratin 6, keratin 16, skin-derived antileukoproteinase, involucrin and transglutaminase 1 expression. The increase in transglutaminase 1 protein is accompanied by an increase in the amount of active transglutaminase 1 enzyme. Surprisingly no increase in keratin 17 is observed. Prolonging the culture period for more than two weeks results in rapid senescence and aging of the cultures. In contrast, keratinocyte growth factor supplemented cultures have a tissue architecture that is similar to healthy native epidermis and remains unchanged for at least 4 weeks of air-exposure. The rate of proliferation and the expression of keratins 6, 16 and 17, skin-derived antileukoproteinase, involucrin and transglutaminase 1 is similar to that found in healthy epidermis and furthermore keratinocyte migration does not occur. When the culture medium is supplemented with a combination of keratinocyte growth factor and a low concentration of epidermal growth factor, skin-derived antileukoproteinase, involucrin and keratins 6, 16 and 17 expression is similar to that found in cultures supplemented with keratinocyte growth factor alone and in healthy epidermis. Only high transglutaminase 1 expression remains similar to that observed in cultures supplemented with epidermal growth factor alone. Our results show that the regulation of keratinocyte growth, migration and differentiation depends on the availability of these growth factors. Epidermal growth factor may play a dominant early role in wound healing by stimulating keratinocyte proliferation and migration while keratinocyte growth factor may play a role later in the repair process by stabilizing epidermal turnover and barrier function.

Development and expression of sensitization to cocaine's reinforcing properties: role of NMDA receptors

Acquisition of cocaine self-administration (0.125, 0.25 or 0.5 mg/kg/infusion) was assessed in rats that had received prior exposure to either saline or amphetamine (2.0 mg/kg). Acquisition of self-administration was dose-dependent, with the highest dose leading to the shortest latency to reliably discriminate between depression of a lever that resulted in drug delivery and an inactive lever. Latency to acquisition of the lever discrimination for rats that had received prior exposure to amphetamine was shorter than for the saline-pretreated counterparts in each cocaine dosage group. This suggests that repeated exposure to this drug prior to self-administration testing sensitized the rats to the reinforcing effects of cocaine. Co-administration of MK-801 (0.25 mg/kg, IP), a non-competitive NMDA antagonist, blocked the ability of chronic exposure to amphetamine to sensitize rats to cocaine. In experienced self-administering rats, acute pretreatment with MK-801 resulted in a loss of discriminative responding. The number of inactive lever responses was consistently higher than the number of active lever responses across all cocaine dosage groups. These data suggest that the NMDA receptor, possibly through interactions with dopamine systems, is critical for both the development and expression of sensitization to cocaine's reinforcing effects produced by intermittent preexposures to amphetamine.

Long-term performance of 555 aortic homografts in the aortic position

Long-term results with 555 aortic homografts used for isolated aortic valve replacement (AVR) between 1964 and 1986 were analyzed to assess valve performance and the time-related onset of valve-related events. The total follow-up was 2,931 patient-years. Twenty years after operation, overall survival was 51.6 +/- 8.1%, freedom from valve-related death was 67.1 +/- 8.9%, freedom from primary tissue failure was 12.4 +/- 4.8%, freedom from infective endocarditis was 82.7 +/- 4.3%, freedom from surgical technical failure was 88.1 +/- 2.3%, and freedom from all complications including valve-related death was 9.0 +/- 3.5%. The incidence of thromboembolism was 0.034% per patient-year (one potential event). Long-term results after homograft insertion for aortic stenosis were significantly better than those after insertion for aortic incompetence. It is concluded that the good quality of life and the median life expectancy, which extends more than 20 years after operation, make the homograft an excellent choice for AVR.

Induction of cytokine (interleukin-1alpha and tumor necrosis factor-alpha) and chemokine (CCL20, CCL27, and CXCL8) alarm signals after allergen and irritant exposure

The immune system is called into action by alarm signals generated from injured tissues. We examined the nature of these alarm signals after exposure of skin residential cells to contact allergens (nickel sulfate and potassium dichromate) and a contact irritant [sodium dodecyl sulfate (SDS)]. Nickel sulfate, potassium dichromate, and SDS were applied topically to the stratum corneum of human skin equivalents. A similar concentration-dependent increase in chemokine (CCL20, CCL27, and CXCL8) secretion was observed for all three chemicals. Exposure to nickel sulfate and SDS was investigated in more detail: similar to chemokine secretion, no difference was observed in the time- and concentration-dependent increase in pro-inflammatory cytokine [interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha)] secretion. Maximal increase in IL-1alpha secretion occurred within 2 h after exposure to both nickel sulfate and SDS and prior to increased chemokine secretion. TNF-alpha secretion was detectable 8 h after chemical exposure. After allergen or irritant exposure, increased CCL20 and CXCL8, but not CCL27, secretion was inhibited by neutralizing human antibodies to either IL-1alpha or TNF-alpha. Our data show that alarm signals consist of primary and secondary signals. IL-1alpha and TNF-alpha are released as primary alarm signals, which trigger the release of secondary chemokine (CCL20 and CXCL8) alarm signals. However, some chemokines, for example, CCL27 can be secreted in an IL-1alpha and TNF-alpha independent manner. Our data suggest that skin residential cells respond to both allergen and irritant exposure by releasing mediators that initiate infiltration of immune responsive cells into the skin.

CXCL8 secretion by dendritic cells predicts contact allergens from irritants

Monocyte-derived dendritic cell functions have been explored for identification of contact allergens in vitro. Current methods, including measurement of changes in cell surface marker expression (e.g. CD83, CD86) do not provide a sensitive method for detecting the sensitising potential of a chemical. In this study, we investigated whether chemokine production by monocyte-derived dendritic cells is increased upon maturation and whether chemokine production can provide methodology for the detection of allergens. Monocyte-derived dendritic cells were exposed to allergens (nickel sulphate, cobalt chloride, palladium chloride, copper sulphate, chrome-(III)-chloride, potassium dichromate, p-phenylenediamine and dinitrochlorobenzene) and irritants (sodium dodecyl sulphate, dimethylsulphoxide, benzalkoniumchloride and propane-1-ol). CD83 and CD86 expression was analysed by flow cytometry and chemokine production (CXCL8, CCL5, CCL17, CCL18, CCL19, CCL20, CCL22) was determined by ELISA. Significant up regulation of CD83 and CD86 expression could only be induced by three out of seven and five out of seven allergens, respectively. In contrast, CXCL8 production was significantly increased after stimulation with all allergens tested, whereas irritant exposure led to decreased CXCL8 production. All other chemokines tested, failed in identifying contact allergens. In conclusion, CXCL8 production, next to CD83 and CD86 up regulation, by monocyte-derived dendritic cells provides a promising in vitro tool for discrimination between allergens and irritants.

Interdependent transcription control elements regulate the expression of the SPRR2A gene during keratinocyte terminal differentiation

Expression of the SPRR2A gene, a member of the small proline-rich family of cornified cell envelope precursor proteins, is strictly linked to keratinocyte terminal differentiation both in vivo and in vitro. In this study, we explored the molecular mechanisms underlying this regulation in transiently transfected primary keratinocytes induced to differentiate in vitro. Deletion mapping and site-directed mutagenesis of SPRR2A promoter-chloramphenicol acetyltransferase constructs indicate that four transcription control elements are essential and sufficient for promoter activity. These elements were further characterized by electrophoretic mobility shift and identified as (i) an inverted octamer doublet, bound by the POU domain factor Oct-11 (Skn-1a/i, Epoc-1), (ii) an interferon-stimulated response element recognized by interferon regulatory factors 1 and 2, (iii) an Ets binding site partially overlapping the interferon-stimulated response element, and (iv) a TG box recognized by the Sp1 family of zinc finger transcription factors. Destruction of a single terminal differentiation element is sufficient to completely abolish transcription from the SPRR2A promoter, indicating that these transcription control elements function in concert in an interdependent manner. Apparently, integration of signals transmitted by the above-mentioned transcription factors is necessary and sufficient to promote gene expression during keratinocyte terminal differentiation.

MR microscopy of multicomponent diffusion in single neurons

This study examines multicomponent diffusion in isolated single neurons and discusses the implications of the results for macroscopic water diffusion in tissues. L7 Aplysia neurons were isolated and analyzed using a 600 MHz Bruker wide-bore instrument with a magnetic susceptibility-matched radiofrequency microcoil. Using a biexponential fit, the apparent diffusion coefficients (ADCs) from the cytoplasm (with relative fraction) were 0.48 +/- 0.14 x 10(-3) mm2 x s(-1) (61 +/- 11%) for the fast component, and 0.034 +/- 0.017 x 10(-3) mm2 x s(-1) (32 +/- 11%) for the slow component (N = 10). Diffusion in the nucleus appears to be primarily monoexponential, but with biexponential analysis it yields 1.31 +/- 0.32 x 10(-3) mm2 x s(-1) (89 +/- 6%) for the fast component and 0.057 +/- 0.073 x 10(-3) mm2 x s(-1) (11 +/- 6%) for the slow (N = 5). The slow component in the nucleus may be explained by cytoplasmic volume averaging. These data demonstrate that water diffusion in the cytoplasm of isolated single Aplysia neurons supports a multiexponential model. The ADCs are consistent with previous measurements in the cytoplasm of single neurons and with the slow ADC measurement in perfused brain slices. These distributions may explain the multiple compartments observed in tissues, greatly aiding the development of quantitative models of MRI in whole tissues.

Prescription Information Leaflets: A National Survey

Three thousand four hundred and ten patients recruited at 254 pharmacies took part in a national postal survey of the effect of prescription information leaflets. The patients had been prescribed penicillins, non-steroidal anti-inflammatory drugs (NSAIDs) or beta-adrenoceptor antagonists. The 1809 patients who received leaflets knew more about their medicines, especially the side effects and were significantly more satisfied than the 1601 patients who were not given additional written information. The leaflets were found to be effective when issued in the north, in the south and in small, medium and large towns. Patients of both sexes, all age groups and social classes were found to benefit from the leaflets and almost everyone (97%) thought they were a good idea. These results confirm and extend our previous findings and add further support for the routine use of information leaflets with prescribed medicines.

NMR spectroscopy of single neurons

The first spatially localized NMR spectra of osmolytes and metabolites from single isolated neurons have been obtained using a combination of high magnetic field strengths and NMR radio frequency (RF) microcoils. The proton spectra display peaks at high concentrations (100-300 mM) assigned to betaine and choline, and other metabolite resonances including lactate at lower concentrations in the order of 10s of millimoles. The volumes examined were approximately 10 nl, over two orders of magnitude less than previously possible. In these initial experiments; the cells were unperfused and the signal intensities of the osmolytes decrease with time, a phenomenon consistent with cell swelling. This work demonstrates the technical feasibility of NMR spectroscopy of single cells, further broadening the scope of NMR spectroscopy of living tissues from application to entire living organisms (man and animal models) and isolated tissues (perfused organs and cultured assemblies of cells) and now to single cells. Magn Reson Med 44:19-22, 2000.

Characterization of the human spr2 promoter: induction after UV irradiation or TPA treatment and regulation during differentiation of cultured primary keratinocytes

We have isolated genomic clones from several members of the UV and TPA inducible human spr2 gene-family in order to analyse the regulation of these genes at a molecular level. From one of these members, the spr2-1 gene, we have identified and sequenced the regulatory region. By using CAT fusion plasmids and a liposome mediated transfection procedure we show that the isolated promoter region contains all the cis-elements necessary for induced expression after UV irradiation or phorbolester treatment of cultured human keratinocytes. Additionally the spr2-1 promoter is shown to be regulated aswell during the normal process of keratinocyte differentiation. This makes the spr2-1 promoter sequence an ideal tool to study the molecular mechanisms by which environmental agents such as UV radiation and chemical tumor promoters interfere with normal gene expression during cell proliferation and differentiation.

Intrinsic regulation of differentiation markers in human epidermis, hard palate and buccal mucosa

Different epithelia show extensive variation in differentiation. Epidermis and epithelium from the hard palate are both typical examples of orthokeratinized epithelia whereas buccal mucosa is an example of a non-keratinized epithelium. Each of these tissues can be distinguished morphologically and also by the expression of a number of structural proteins. Tissue explants derived from epidermis, hard palate or buccal mucosa were cultured at the air-liquid interface on collagen gels containing human dermal fibroblasts. Reconstructed epithelia that retained many of the morphological and immunohistochemical characteristics of the original tissue were formed. Cultures derived from epidermis and the hard palate both had a well-defined stratum basale, stratum spinosum, stratum granulosum and stratum corneum whereas cultures derived from buccal mucosa had no stratum granulosum or corneum and the cells retained their nuclei. Significantly more living cell layers were observed in both types of epithelia obtained from the mouth than in epidermis. The specific localization of proliferation and differentiation markers (Ki67, loricrin, involucrin, SPRR2, SPRR3 and keratin 10) closely resembled that of the tissue from which the cultures were derived. As identical three-dimensional culture models were used here, it is concluded that the differences observed between these epithelia were due to intrinsic properties of the keratinocytes.

Autologous full-thickness skin substitute for healing chronic wounds

BACKGROUND

Chronic wounds represent a major problem to our society. Therefore, advanced wound-healing strategies for the treatment of these wounds are expanding into the field of tissue engineering.

OBJECTIVES

To develop a novel tissue-engineered, autologous, full-thickness skin substitute of entirely human origin and to determine its ability to heal chronic wounds.

METHODS

Skin substitutes (fully differentiated epidermis on fibroblast-populated human dermis) were constructed from 3-mm punch biopsies isolated from patients to be treated. Acellular allodermis was used as a dermal matrix. After a prior 5-day vacuum-assisted closure therapy to prepare the wound bed, skin substitutes were applied in a simple one-step surgical procedure to 19 long-standing recalcitrant leg ulcers (14 patients; ulcer duration 0.5-50 years).

RESULTS

The success rate in culturing biopsies was 97%. The skin substitute visibly resembled an autograft. Eleven of the 19 ulcers (size 1-10 cm2) healed within 8 weeks after a single application of the skin substitute. The other eight larger (60-150 cm2) and/or complicated ulcers healed completely (n = 5) or continued to decrease substantially in size (n = 3) after the 8-week follow-up period. Wound healing occurred by direct take of the skin substitute (n = 12) and/or stimulation of granulation tissue/epithelialization (n = 7). Skin substitutes were very well tolerated and pain relief was immediate after application.

CONCLUSIONS

Application of this novel skin substitute provides a promising new therapy for healing chronic wounds resistant to conventional therapies.