Persistence and biodegradation of oil at the ocean floor following Deepwater Horizon.

The 2010 Deepwater Horizon disaster introduced an unprecedented discharge of oil into the deep Gulf of Mexico. Considerable uncertainty has persisted regarding the oil's fate and effects in the deep ocean. In this work we assess the compound-specific rates of biodegradation for 125 aliphatic, aromatic, and biomarker petroleum hydrocarbons that settled to the deep ocean floor following release from the damaged Macondo Well. Based on a dataset comprising measurements of up to 168 distinct hydrocarbon analytes in 2,980 sediment samples collected within 4 y of the spill, we develop a Macondo oil "fingerprint" and conservatively identify a subset of 312 surficial samples consistent with contamination by Macondo oil. Three trends emerge from analysis of the biodegradation rates of 125 individual hydrocarbons in these samples. First, molecular structure served to modulate biodegradation in a predictable fashion, with the simplest structures subject to fastest loss, indicating that biodegradation in the deep ocean progresses similarly to other environments. Second, for many alkanes and polycyclic aromatic hydrocarbons biodegradation occurred in two distinct phases, consistent with rapid loss while oil particles remained suspended followed by slow loss after deposition to the seafloor. Third, the extent of biodegradation for any given sample was influenced by the hydrocarbon content, leading to substantially greater hydrocarbon persistence among the more highly contaminated samples. In addition, under some conditions we find strong evidence for extensive degradation of numerous petroleum biomarkers, notably including the native internal standard 17α(H),21ß(H)-hopane, commonly used to calculate the extent of oil weathering.

Mio-Pliocene aridity in the south-central Andes associated with Southern Hemisphere cold periods.

Although Earth's climate history is best known through marine records, the corresponding continental climatic conditions drive the evolution of terrestrial life. Continental conditions during the latest Miocene are of particular interest because global faunal turnover is roughly synchronous with a period of global glaciation from ∼6.2-5.5 Ma and with the Messinian Salinity Crisis from ∼6.0-5.3 Ma. Despite the climatic and ecological significance of this period, the continental climatic conditions associated with it remain unclear. We address this question using erosion rates of ancient watersheds to constrain Mio-Pliocene climatic conditions in the south-central Andes near 30° S. Our results show two slowdowns in erosion rate, one from ∼6.1-5.2 Ma and another from 3.6 to 3.3 Ma, which we attribute to periods of continental aridity. This view is supported by synchrony with other regional proxies for aridity and with the timing of glacial ?cold" periods as recorded by marine proxies, such as the M2 isotope excursion. We thus conclude that aridity in the south-central Andes is associated with cold periods at high southern latitudes, perhaps due to a northward migration of the Southern Hemisphere westerlies, which disrupted the South American Low Level Jet that delivers moisture to southeastern South America. Colder glacial periods, and possibly associated reductions in atmospheric CO2, thus seem to be an important driver of Mio-Pliocene ecological transitions in the central Andes. Finally, this study demonstrates that paleo-erosion rates can be a powerful proxy for ancient continental climates that lie beyond the reach of most lacustrine and glacial archives.

Severe disruption and disorganization of dermal collagen fibrils in early striae gravidarum.

BACKGROUND: Striae gravidarum (SG), or stretch marks of pregnancy, begin as erythematous streaks and mature into hypopigmented atrophic bands. OBJECTIVES: In order to investigate molecular alterations that may promote atrophy of SG, we investigated dermal type I collagen fibrils, which provide human skin with support. METHODS: We obtained skin samples of recently developed, erythematous abdominal SG from pregnant women. To examine the organization of collagen fibrils, second-harmonic generation imaging was performed using multiphoton microscopy. Immunostaining was used to determine protein expression and localization of type I procollagen, the precursor of type I collagen fibrils. Real-time polymerase chain reaction was used to determine gene expression levels. RESULTS: In control (hip) and stretched normal-appearing perilesional abdominal skin, dermal collagen fibrils were organized as tightly packed, interwoven bundles. In SG, collagen bundles appeared markedly separated, especially in the mid-to-deep dermis. In the spaces separating these bundles, loosely packed wavy collagen fibrils lacking organization as bundles were present. These disorganized fibrils persisted into the postpartum period and failed to form densely packed bundles. Numerous large fibroblasts displaying type I procollagen expression were in close proximity to the disorganized fibrils, suggesting that the fibrils are newly synthesized. Supporting this possibility, immunostaining and gene expression of type I procollagen were increased throughout the dermis of SG. CONCLUSIONS: Early SG display marked separation of collagen bundles and emergence of disorganized collagen fibrils that fail to form bundles. These alterations may reflect ineffective repair of collagen bundles disrupted by intense skin stretching. Persistent disruption of the collagenous extracellular matrix likely promotes formation and atrophy of SG.

Fallout plume of submerged oil from Deepwater Horizon.

The sinking of the Deepwater Horizon in the Gulf of Mexico led to uncontrolled emission of oil to the ocean, with an official government estimate of ∼ 5.0 million barrels released. Among the pressing uncertainties surrounding this event is the fate of ∼ 2 million barrels of submerged oil thought to have been trapped in deep-ocean intrusion layers at depths of ∼ 1,000-1,300 m. Here we use chemical distributions of hydrocarbons in >3,000 sediment samples from 534 locations to describe a footprint of oil deposited on the deep-ocean floor. Using a recalcitrant biomarker of crude oil, 17α(H),21ß(H)-hopane (hopane), we have identified a 3,200-km(2) region around the Macondo Well contaminated by ∼ 1.8 ± 1.0 × 10(6) g of excess hopane. Based on spatial, chemical, oceanographic, and mass balance considerations, we calculate that this contamination represents 4-31% of the oil sequestered in the deep ocean. The pattern of contamination points to deep-ocean intrusion layers as the source and is most consistent with dual modes of deposition: a "bathtub ring" formed from an oil-rich layer of water impinging laterally upon the continental slope (at a depth of ∼ 900-1,300 m) and a higher-flux "fallout plume" where suspended oil particles sank to underlying sediment (at a depth of ∼ 1,300-1,700 m). We also suggest that a significant quantity of oil was deposited on the ocean floor outside this area but so far has evaded detection because of its heterogeneous spatial distribution.

Molecular basis of retinol anti-ageing properties in naturally aged human skin in vivo.

OBJECTIVE: Retinoic acid has been shown to improve the aged-appearing skin. However, less is known about the anti-ageing effects of retinol (ROL, vitamin A), a precursor of retinoic acid, in aged human skin in vivo. This study aimed to investigate the molecular basis of ROL anti-ageing properties in naturally aged human skin in vivo. METHODS: Sun-protected buttock skin (76 ± 6 years old, n = 12) was topically treated with 0.4% ROL and its vehicle for 7 days. The effects of topical ROL on skin epidermis and dermis were evaluated by immunohistochemistry, in situ hybridization, Northern analysis, real-time RT-PCR and Western analysis. Collagen fibrils nanoscale structure and surface topology were analysed by atomic force microscopy. RESULTS: Topical ROL shows remarkable anti-ageing effects through three major types of skin cells: epidermal keratinocytes, dermal endothelial cells and fibroblasts. Topical ROL significantly increased epidermal thickness by stimulating keratinocytes proliferation and upregulation of c-Jun transcription factor. In addition to epidermal changes, topical ROL significantly improved dermal extracellular matrix (ECM) microenvironment; increasing dermal vascularity by stimulating endothelial cells proliferation and ECM production (type I collagen, fibronectin and elastin) by activating dermal fibroblasts. Topical ROL also stimulates TGF-ß/CTGF pathway, the major regulator of ECM homeostasis, and thus enriched the deposition of ECM in aged human skin in vivo. 0.4% topical ROL achieved similar results as seen with topical retinoic acid, the biologically active form of ROL, without causing noticeable signs of retinoid side effects. CONCLUSION: 0.4% topical ROL shows remarkable anti-ageing effects through improvement of the homeostasis of epidermis and dermis by stimulating the proliferation of keratinocytes and endothelial cells, and activating dermal fibroblasts. These data provide evidence that 0.4% topical ROL is a promising and safe treatment to improve the naturally aged human skin.

Autonomous Marine Robotic Technology Reveals an Expansive Benthic Bacterial Community Relevant to Regional Nitrogen Biogeochemistry.

Benthic accumulations of filamentous, mat-forming bacteria occur throughout the oceans where bisulfide mingles with oxygen or nitrate, providing key but poorly quantified linkages between elemental cycles of carbon, nitrogen and sulfur. Here we used the autonomous underwater vehicle Sentry to conduct a contiguous, 12.5 km photoimaging survey of sea-floor colonies of filamentous bacteria between 80 and 579 m water depth, spanning the continental shelf to the deep suboxic waters of the Santa Barbara Basin (SBB). The survey provided >31 000 images and revealed contiguous, white-colored bacterial colonization coating > ∼80% of the ocean floor and spanning over 1.6 km, between 487 and 523 m water depth. Based on their localization within the stratified waters of the SBB we hypothesize a dynamic and annular biogeochemical zonation by which the bacteria capitalize on periodic flushing events to accumulate and utilize nitrate. Oceanographic time series data bracket the imaging survey and indicate rapid and contemporaneous nitrate loss, while autonomous capture of microbial communities from the benthic boundary layer concurrent with imaging provides possible identities for the responsible bacteria. Based on these observations we explore the ecological context of such mats and their possible importance in the nitrogen cycle of the SBB.

Validation of an RNA cell cycle progression score for predicting death from prostate cancer in a conservatively managed needle biopsy cohort.

BACKGROUND: The natural history of prostate cancer is highly variable and difficult to predict accurately. Better markers are needed to guide management and avoid unnecessary treatment. In this study, we validate the prognostic value of a cell cycle progression score (CCP score) independently and in a prespecified linear combination with standard clinical variables, that is, a clinical-cell-cycle-risk (CCR) score. METHODS: Paraffin sections from 761 men with clinically localized prostate cancer diagnosed by needle biopsy and managed conservatively in the United Kingdom, mostly between 2000 and 2003. The primary end point was prostate cancer death. Clinical variables consisted of centrally reviewed Gleason score, baseline PSA level, age, clinical stage, and extent of disease; these were combined into a single predefined risk assessment (CAPRA) score. Full data were available for 585 men who formed a fully independent validation cohort. RESULTS: In univariate analysis, the CCP score hazard ratio was 2.08 (95% CI (1.76, 2.46), P<10(-13)) for one unit change of the score. In multivariate analysis including CAPRA, the CCP score hazard ratio was 1.76 (95% CI (1.44, 2.14), P<10(-6)). The predefined CCR score was highly predictive, hazard ratio 2.17 (95% CI (1.83, 2.57), χ(2)=89.0, P<10(-20)) and captured virtually all available prognostic information. CONCLUSIONS: The CCP score provides significant pretreatment prognostic information that cannot be provided by clinical variables and is useful for determining which patients can be safely managed conservatively, avoiding radical treatment.

Marked disruption and aberrant regulation of elastic fibres in early striae gravidarum.

BACKGROUND: Striae gravidarum (SG), or 'stretch marks' of pregnancy, begin as erythematous streaks, and mature over months to years to become permanent scar-like bands that may be hypopigmented, atrophic and lax. OBJECTIVES: To investigate early molecular alterations that may promote laxity of mature SG, we investigated the dermal elastic fibre network, which provides human skin with elastic properties. METHODS: We obtained skin samples of newly developed, erythematous abdominal SG in healthy pregnant women. The elastic fibre network was examined by Verhoeff elastic staining and immunofluorescence staining of skin sections. Gene expression was measured by real-time polymerase chain reaction. RESULTS: The normal elastic fibre network appeared markedly disrupted in SG, compared with perilesional abdominal skin or control (normal-appearing hip skin). This disruption was accompanied by the emergence of short, disorganized, thin, thread-like 'fibrils', which were observed prominently in the mid-to-deep dermis. These fibrils were rich in tropoelastin (the main component of normal elastic fibres), and persisted into the postpartum period without forming normal-appearing elastic fibres. The emergence of these fibrils was accompanied by increased gene expression of tropoelastin and fibrillin-1, but not other elastic fibre components, including fibrillin-2 and fibulin-1, -2 or -5. CONCLUSIONS: In early SG, the elastic fibre network appears markedly disrupted, and newly synthesized tropoelastin-rich fibrils emerge, likely as a result of uncoordinated synthesis of elastic fibre components. Because they are thin and disorganized, tropoelastin-rich fibrils likely do not function as normal elastic fibres do. These observations provide the foundations for elucidating pathogenic mechanisms by which laxity may develop in SG.

Focal amplification of the androgen receptor gene in hormone-naive human prostate cancer.

BACKGROUND: Androgen receptor (AR)-gene amplification, found in 20-30% of castration-resistant prostate cancer (CRPCa) is proposed to develop as a consequence of hormone-deprivation therapy and be a prime cause of treatment failure. Here we investigate AR-gene amplification in cancers before hormone deprivation therapy. METHODS: A tissue microarray (TMA) series of 596 hormone-naive prostate cancers (HNPCas) was screened for chromosome X and AR-gene locus-specific copy number alterations using four-colour fluorescence in situ hybridisation. RESULTS: Both high level gain in chromosome X (≥4 fold; n=4, 0.7%) and locus-specific amplification of the AR-gene (n=6, 1%) were detected at low frequencies in HNPCa TMAs. Fluorescence in situ hybridisation mapping whole sections taken from the original HNPCa specimen blocks demonstrated that AR-gene amplifications exist in small foci of cells (≤ 600 nm, ≤1% of tumour volume). Patients with AR gene-locus-specific copy number gains had poorer prostate cancer-specific survival. CONCLUSION: Small clonal foci of cancer containing high level gain of the androgen receptor (AR)-gene develop before hormone deprivation therapy. Their small size makes detection by TMA inefficient and suggests a higher prevalence than that reported herein. It is hypothesised that a large proportion of AR-amplified CRPCa could pre-date hormone deprivation therapy and that these patients would potentially benefit from early total androgen ablation.

A multicenter phase II study of pazopanib in patients with advanced gastrointestinal stromal tumors (GIST) following failure of at least imatinib and sunitinib.

BACKGROUND: Advanced GISTs are incurable, but often treatable for years with tyrosine kinase inhibitors (TKIs). The majority of GISTs harbor an oncogenic activating mutation in KIT or PDGFRA. Inhibition of this activating mutation with TKIs most often leads to durable disease control for many patients. However, almost all patients develop resistance to these TKIs, typically due to the development of secondary mutations, heralding the need for new therapeutic options. We conducted a phase II study evaluating the efficacy and toxicity of pazopanib, a broad spectrum TKI inhibiting KIT, VEGFRs (-1, -2, and -3), and PDGFR (-α and-ß) in patients with advanced GIST following failure of at least imatinib and sunitinib. METHODS: Patients received pazopanib 800 mg orally once daily. All patients were assessed for efficacy with CT scans every 8 weeks (two cycles). Patients continued pazopanib until progression or unacceptable toxicity. The primary end point was the 24-week nonprogression [complete response+partial response+stable disease (SD)] rate (NPR) per RECIST 1.1. Secondary end points included PFS, OS, and toxicity. RESULTS: Between August 2011 and September 2012, a total of 25 patients were treated at two institutions. Median number of prior therapy was 3 (range 2-7). A total of 90 cycles of pazopanib were administered, with a median of two cycles (range 1 to 17+) per patient. Best response of SD at any time was observed in 12 (48%) patients. The NPR was 17% [95% confidence interval (CI) 4.5-37]. All but one patient discontinued protocol either due to PD (n = 19) or intolerance (n = 4). One patient with succinate dehydrogenase (SDH)-deficient GIST exhibited continuing disease control after 17 cycles. The median PFS for the entire cohort was 1.9 months (95% CI 1.6-5.2), and the median OS was 10.7 months (95% CI 3.9-NR). CONCLUSIONS: Pazopanib was reasonably well tolerated with no unexpected toxicities. Pazopanib as a single agent has marginal activity in unselected heavily pretreated patients with advanced GIST.

Prognostic value of Ki-67 for prostate cancer death in a conservatively managed cohort.

BACKGROUND: Standard clinical parameters cannot accurately differentiate indolent from aggressive prostate cancer. Our previous work showed that immunohistochemical (IHC) Ki-67 improved prediction of prostate cancer death in a cohort of conservatively treated clinically localised prostate cancers diagnosed by transurethral resection of the prostate (TURP). Here, we present results in a more clinically relevant needle biopsy cohort. METHODS: Biopsy specimens were microarrayed. The percentage of Ki-67 positively stained malignant cells per core was measured and the maximum score per individual used in analysis of time to death from prostate cancer using a Cox proportional hazards model. RESULTS: In univariate analysis (n=293), the hazard ratio (HR) (95% confidence intervals) for dichotomous Ki-67 (≤ 10%, >10%) was 3.42 (1.76, 6.62) χ(2) (1 df)=9.8, P=0.002. In multivariate analysis, Ki-67 added significant predictive information to that provided by Gleason score and prostate-specific antigen (HR=2.78 (1.42, 5.46), χ(2) (1 df)=7.0, P=0.008). CONCLUSION: The IHC Ki-67 scoring on prostate needle biopsies is practicable and yielded significant prognostic information. It was less informative than in the previous TURP cohort where tumour samples were larger and more comprehensive, but in more contemporary cohorts with larger numbers of biopsies per patient, Ki-67 may prove a more powerful biomarker.

Mir143 expression inversely correlates with nuclear ERK5 immunoreactivity in clinical prostate cancer.

BACKGROUND: Aberrant mitogen/extracellular signal-regulated kinase 5 (MEK5)-extracellular signal-regulated protein kinase 5 (ERK5)-mediated signalling has been implicated in a number of tumour types including prostate cancer (CaP). The mechanism for ERK5 activation in CaP remains to be fully elucidated. Studies have recently implicated the role of microRNA (miRNA) mir143 expression in the regulation of ERK5 expression. METHODS: We utilised a tissue microarray (TMA) of 530 CaP cores from 168 individual patients and stained for both mir143 and ERK5. These TMAs were scored by a combination of observer and automated methods. RESULTS: We observed a strong inverse relation between ERK5 and mir143, which manifested itself most strongly in the subgroup of 417 cores with non-zero mir143 and ERK5 immunoreactivity, or with only one of mir143 or ERK5 being zero (cc=0.2558 and P<0.0001). Mir143 neither correlate with Gleason scores or prostate-specific antigen levels, nor was it a predictor of disease-specific survival on univariate analysis. CONCLUSION: Although the mechanism for ERK5 activation in CaP remains to be fully elucidated, we have further validated the potential role of mir143 in regulating ERK5 levels in the clinical context. In addition, we demonstrate that the automated counting method for nuclear ERK5 is a clinically useful alterative to observer counting method in patient stratification in the context of ERK5 targeting therapy.

Prognostic value of PTEN loss in men with conservatively managed localised prostate cancer.

BACKGROUND: The natural history of prostate cancer is highly variable and difficult to predict. We report on the prognostic value of phosphatase and tensin homologue (PTEN) loss in a cohort of 675 men with conservatively managed prostate cancer diagnosed by transurethral resection of the prostate. METHODS: The PTEN status was assayed by immunohistochemistry (PTEN IHC) and fluorescent in situ hybridisation (PTEN FISH). The primary end point was death from prostate cancer. RESULTS: The PTEN IHC loss was observed in 18% cases. This was significantly associated with prostate cancer death in univariate analysis (hazard ratio (HR)=3.51; 95% CI 2.60-4.73; P=3.1 × 10(-14)). It was highly predictive of prostate cancer death in the 50% of patients with a low risk score based on Gleason score, PSA, Ki-67 and extent of disease (HR=7.4; 95% CI 2.2-24.6; P=0.012) ), but had no prognostic value in the higher risk patients. The PTEN FISH loss was only weakly associated with PTEN IHC loss (κ=0.5). Both PTEN FISH loss and amplification were univariately predictive of death from prostate cancer, but this was not maintained in the multivariate analyses. CONCLUSION: In low-risk patients, PTEN IHC loss adds prognostic value to Gleason score, PSA, Ki-67 and extent of disease.

Preliminary findings of fecal gonadal hormone concentrations in six captive sea otters (Enhydra lutris) after deslorelin implantation.

The sea otter (Enhydra lutris) is a popular exhibit animal in many zoos and aquariums worldwide. Captive sea otters from these populations are owned by the United States Fish and Wildlife Service (USFWS). The USFWS has requested that these sea otters be prevented from breeding in order to save captive space for wild rescued animals. Sea otters are often housed in mixed sex groups, therefore a chemical contraceptive method or surgical removal of gonads must be used to prevent potential pregnancy. The contraceptive, Suprelorin® or deslorelin, has been used in many different species to effectively suppress reproduction but duration of effect may vary not only between species but also individuals. Here, we report the effects of one to several consecutive deslorelin implants on gonadal reproductive hormones found in fecal samples from six captive sea otters (two males and four females) compared to two control otters (one male and one female) housed at three zoological institutions. We documented the longitudinal hormone signatures of many stages of the contraceptive cycle including pretreatment (PT), stimulatory phase (S), effective contraception (EC), and hormone reversal (HR) that was characterized by a return to normal hormone levels. Deslorelin was found to be an effective contraceptive in sea otters and was found to be reversible documented by a live birth following treatment, however the duration of suppression in females was much longer than expected with a 6-month and a 1-year implant lasting between 3 and 4 years in females.

Influence of a low-dose cox-2 inhibitor drug on exercise-induced inflammation, muscle damage and lipid peroxidation.

The purpose of this study was to examine the effect of acute low-dose celecoxib administration on exercise-induced inflammation, muscle damage and lipid peroxidation. Twenty healthy untrained males (age: 25.5±4.5 yrs, weight: 72.7±7.9 kg, height: 177.3±7.2 cm) were randomly assigned to treatment (T) or placebo (P) groups. Blood samples were obtained before, immediately after, 3 h after and 24 h after exercise. Subjects ran for 30 min at 75% [Formula: see text]O2 max on a treadmill. Participants consumed 100 mg celecoxib or a placebo immediately after and 12 h after the immediately post-exercise blood sample. Total leukocytes, neutrophils, creatine kinase (CK), C-reactive protein (CRP) and malondialdehyde (MDA) were assessed at each time point. Significant increases in total leukocytes and neutrophils were observed 3 h after exercise in both groups (P < 0.05). CK and CRP levels were significantly increased immediately, 3 h and 24 h after exercise in both groups (P < 0.05). A significant increase in MDA was observed immediately after exercise in both groups (P < 0.05); however, no significant group differences were observed for MDA or CK. These findings suggest that inhibition of cyclo-oxygenase activity with low-dose celecoxib does not affect exercise-induced inflammation, muscle damage, or lipid peroxidation.

Milankovitch-paced erosion in the southern Central Andes.

It has long been hypothesized that climate can modify both the pattern and magnitude of erosion in mountainous landscapes, thereby controlling morphology, rates of deformation, and potentially modulating global carbon and nutrient cycles through weathering feedbacks. Although conceptually appealing, geologic evidence for a direct climatic control on erosion has remained ambiguous owing to a lack of high-resolution, long-term terrestrial records and suitable field sites. Here we provide direct terrestrial field evidence for long-term synchrony between erosion rates and Milankovitch-driven, 400-kyr eccentricity cycles using a Plio-Pleistocene cosmogenic radionuclide paleo-erosion rate record from the southern Central Andes. The observed climate-erosion coupling across multiple orbital cycles, when combined with results from the intermediate complexity climate model CLIMBER-2, are consistent with the hypothesis that relatively modest fluctuations in precipitation can cause synchronous and nonlinear responses in erosion rates as landscapes adjust to ever-evolving hydrologic boundary conditions imposed by oscillating climate regimes.

Prognostic value of a cell cycle progression signature for prostate cancer death in a conservatively managed needle biopsy cohort.

BACKGROUND: The natural history of prostate cancer is highly variable and it is difficult to predict. We showed previously that a cell cycle progression (CCP) score was a robust predictor of outcome in a conservatively managed cohort diagnosed by transurethral resection of the prostate. A greater need is to predict outcome in patients diagnosed by needle biopsy. METHODS: Total RNA was extracted from paraffin specimens. A CCP score was calculated from expression levels of 31 genes. Clinical variables consisted of centrally re-reviewed Gleason score, baseline prostate-specific antigen level, age, clinical stage, and extent of disease. The primary endpoint was death from prostate cancer. RESULTS: In univariate analysis (n=349), the hazard ratio (HR) for death from prostate cancer was 2.02 (95% CI (1.62, 2.53), P<10(-9)) for a one-unit increase in CCP score. The CCP score was only weakly correlated with standard prognostic factors and in a multivariate analysis, CCP score dominated (HR for one-unit increase=1.65, 95% CI (1.31, 2.09), P=3 × 10(-5)), with Gleason score (P=5 × 10(-4)) and prostate-specific antigen (PSA) (P=0.017) providing significant additional contributions. CONCLUSION: For conservatively managed patients, the CCP score is the strongest independent predictor of cancer death outcome yet described and may prove valuable in managing clinically localised prostate cancer.

Etanercept suppresses regenerative hyperplasia in psoriasis by acutely downregulating epidermal expression of interleukin (IL)-19, IL-20 and IL-24.

BACKGROUND: Psoriasis is a Th17/Th1-mediated skin disease that often responds to antitumour necrosis factor (TNF)-α therapies, such as etanercept. OBJECTIVES: To better define mechanisms by which etanercept improves psoriasis and to gain insight into disease pathogenesis. METHODS: We investigated the early biochemical and cellular effects of etanercept on skin lesions in responder patients prior to substantial clinical improvement (≤ 4 weeks). RESULTS: By 1 week, etanercept acutely suppressed gene expression of the interleukin (IL)-20 subfamily of cytokines (IL-19, IL-20, IL-24), which were found to be predominantly epidermis-derived and which are implicated in stimulating epidermal hyperplasia. Additionally, by 1 week of therapy, suppression of other keratinocyte-derived products (chemokines, antimicrobial proteins) occurred, while suppression of epidermal regenerative hyperplasia occurred within 1-3 weeks. Th17 elements (IL-23p19, IL-12p40, IL-17A, IL-22) were suppressed by 3-4 weeks. In vitro, TNF-α and IL-17A coordinately stimulated the expression of the IL-20 subfamily in normal keratinocytes. CONCLUSIONS: Based on the rapid suppression of regenerative hyperplasia, chemokines and other keratinocyte-derived products, including the IL-20 subfamily, we propose that epidermal activation is a very early target of etanercept. As many of these keratinocyte markers are stimulated by TNF-α, their rapid downregulation is likely to reflect etanercept's antagonism of TNF-α. Additionally, decreased epidermal hyperplasia might result specifically from acute suppression of the IL-20 subfamily, which is also a likely consequence of etanercept's antagonism of TNF-α. Thus, the IL-20 subfamily has potential importance in the pathogenesis of psoriasis and therapeutic response to etanercept.

Acute regulation of IGF-I by alterations in post-exercise macronutrients.

This investigation sought to examine the contributions of exercise and nutrient replenishment on in vivo regulation of the insulin-like growth factor-I (IGF-I) axis components. Eight college-aged males completed three high-intensity interval training (HIIT) protocols followed by three post-exercise nutritional protocols: (1) placebo (EX); (2) carbohydrate only (CHO); and (3) essential amino acid/carbohydrate (EAA/CHO). Samples were analyzed for growth hormone (GH), free IGF-I, IGFBP-1, IGFBP-2, insulin, hematocrit, hemoglobin, serum leucine, matrix metalloproteinase-9 (MMP-9) proteolytic activity, and presence of IGFBP-3 protease activity. No evidence for IGFBP-3 proteolysis was observed. Significant increases in [free IGF-I] and [leucine] were observed in the EAA/CHO group only. Significant differences were noted in [IGFBP-1] and [IGFBP-2] across conditions. Significant increases in [GH] and MMP-9 activity were observed in all groups. These results indicate that post-exercise macronutrient ratio is a determinant of [free IGF-I], [IGFBP-1 and -2] and may play a role in modulating the IGF-I axis in vivo.

Nitroreductase/Metronidazole-Mediated Ablation and a MATLAB Platform (RpEGEN) for Studying Regeneration of the Zebrafish Retinal Pigment Epithelium.

The retinal pigment epithelium (RPE) resides at the back of the eye and performs functions essential for maintaining the health and integrity of adjacent retinal and vascular tissues. At present, the limited reparative capacity of mammalian RPE, which is restricted to small injuries, has hindered progress to understanding in vivo RPE regenerative processes. Here, a detailed methodology is provided to facilitate the study of in vivo RPE repair utilizing the zebrafish, a vertebrate model capable of robust tissue regeneration. This protocol describes a transgenic nitroreductase/metronidazole (NTR/MTZ)-mediated injury paradigm (rpe65a:nfsB-eGFP), which results in ablation of the central two-thirds of the RPE after 24 h treatment with MTZ, with subsequent tissue recovery. Focus is placed on RPE ablations in larval zebrafish and methods for testing the effects of pharmacological compounds on RPE regeneration are also outlined. Generation and validation of RpEGEN, a MATLAB script created to automate quantification of RPE regeneration based on pigmentation, is also discussed. Beyond active RPE repair mechanisms, this protocol can be expanded to studies of RPE degeneration and injury responses as well as the effects of RPE damage on adjacent retinal and vascular tissues, among other cellular and molecular processes. This zebrafish system holds significant promise in identifying genes, networks, and processes that drive RPE regeneration and RPE disease-related mechanisms, with the long-term goal of applying this knowledge to mammalian systems and, ultimately, toward therapeutic development.