940 resultados para investigate significance of mining places


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BACKGROUND: The intracellular signalling mechanisms that regulate ovarian follicle development are unclear; however, we have recently shown differences in the Akt and Erk signalling pathways in dominant compared to subordinate follicles. The aim of this study was to investigate the effects of inhibiting Akt and Erk phosphorylation on IGF- and gonadotropin- stimulated granulosa and theca cell function in vitro, and on follicle development in vivo. METHODS: Bovine granulosa and theca cells were cultured for six days and stimulated with FSH and/or IGF, or LH in combination with PD98059 (Erk inhibitor) and/or LY294002 (Akt inhibitor) and their effect on cell number and hormone secretion (estradiol, activin-A, inhibin-A, follistatin, progesterone and androstenedione) determined. In addition, ovarian follicles were treated in vivo with PD98059 and/or LY294002 in ewes on Day 3 of the cycle and follicles were recovered 48 hours later. RESULTS: We have shown that gonadotropin- and IGF-stimulated hormone production by granulosa and theca cells is reduced by treatment with PD98059 and LY294002 in vitro. Furthermore, treatment with PD98059 and LY294002 reduced follicle growth and oestradiol production in vivo. CONCLUSION: These results demonstrate an important functional role for the Akt and Erk signalling pathways in follicle function, growth and development.

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Objectives: This study aimed to investigate the efficacy of St. John's wort extract (SJW) as a treatment for premenstrual symptoms. Design: The study was a randomized, double-blinded, placebo-controlled trial, with two parallel treatment groups. After a no-treatment baseline cycle, volunteers were randomized to either SJW or placebo for a further two menstrual cycles. Settings/location: A postal trial conducted from The University of Reading, Berkshire, England. Subjects: One hundred and sixty-nine (169) normally menstruating women who experienced recurrent premenstrual symptoms were recruited onto the study. One hundred and twenty-five (125) completed the protocol and were included in the analysis. Interventions: Six hundred milligrams (600) mg of SJW (standardized to contain 1800 mug of hypericin) or placebo (containing lactose and cellulose). Outcome measure: A menstrual diary was used to assess changes in premenstrual symptoms. The anxiety-related subgroup of symptoms of this instrument was used as the primary outcome measure. Results: After averaging the effects of treatment over both treatment cycles it was found that there was a trend for SJW to be superior to placebo. However, this finding was not statistically significant. Conclusion: The possibility that this nonsignificant finding resulted from insufficient statistical power in the study, rather than a lack of efficacy of SJW, is discussed. Following this discussion the recommendation is made that, in future, similar studies should be powered to detect a minimum clinically relevant difference between treatments.

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Objectives: This study aimed to investigate the efficacy of St. John's wort extract (SJW) as a treatment for premenstrual symptoms. Design: The study was a randomized, double-blinded, placebo-controlled trial, with two parallel treatment groups. After a no-treatment baseline cycle, volunteers were randomized to either SJW or placebo for a further two menstrual cycles. Settings/location: A postal trial conducted from The University of Reading, Berkshire, England. Subjects: One hundred and sixty-nine (169) normally menstruating women who experienced recurrent premenstrual symptoms were recruited onto the study. One hundred and twenty-five (125) completed the protocol and were included in the analysis. Interventions: Six hundred milligrams (600) mg of SJW (standardized to contain 1800 mug of hypericin) or placebo (containing lactose and cellulose). Outcome measure: A menstrual diary was used to assess changes in premenstrual symptoms. The anxiety-related subgroup of symptoms of this instrument was used as the primary outcome measure. Results: After averaging the effects of treatment over both treatment cycles it was found that there was a trend for SJW to be superior to placebo. However, this finding was not statistically significant. Conclusion: The possibility that this nonsignificant finding resulted from insufficient statistical power in the study, rather than a lack of efficacy of SJW, is discussed. Following this discussion the recommendation is made that, in future, similar studies should be powered to detect a minimum clinically relevant difference between treatments.

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The question as to whether it is better to diversify a real estate portfolio within a property type across the regions or within a region across the property types is one of continuing interest for academics and practitioners alike. The current study, however, is somewhat different from the usual sector/regional analysis taking account of the fact that holdings in the UK real estate market are heavily concentrated in a single region, London. As a result this study is designed to investigate whether a real estate fund manager can obtain a statistically significant improvement in risk/return performance from extending out of a London based portfolio into firstly the rest of the South East of England and then into the remainder of the UK, or whether the manger would be better off staying within London and diversifying across the various property types. The results indicating that staying within London and diversifying across the various property types may offer performance comparable with regional diversification, although this conclusion largely depends on the time period and the fund manager’s ability to diversify efficiently.

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Mining started in South Australia in the early 1840s with the discovery of silver-lead ore at Glen Osmond in 1841 and later copper in Kapunda in 1842 and Burra in 1845; all these discoveries greatly contributed to South Australia's economic development. South Australia entered the mining era at the time when the Cornish engine was at the peak of its development, and the horizontal engine was beginning its rise in popularity. These South Australian historic mining sites contain extensive extant evidence of technology, innovation and human endeavours that previously went into the mining activity. This paper seeks to critically review items for inclusion on the South Australian State Heritage Register, the character of mining heritage places, enforcement by legislation, interpretation of the heritage assessment and how these practices could guide Malaysia in recognizing industrial heritage as a significant part of its cultural heritage that needs to be conserved, restored and managed as a legacy for present and future generations.

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The jeju is a teleost fish with bimodal respiration that utilizes a modified swim bladder as an air-breathing organ (ABO). Like all air-breathing fish studied to date, jeju exhibit pronounced changes in heart rate (f(H)) during air-breathing events, and it is believed that these may facilitate oxygen uptake (M-O2) from the ABO. The current study employed power spectral analysis (PSA) of f(H) patterns, coupled with instantaneous respirometry, to investigate the autonomic control of these phenomena and their functional significance for the efficacy of air breathing. The jeju obtained less than 5% of total M-O2 (M-tO2) from air breathing in normoxia at 26 degrees C, and PSA of beat-to-beat variability in fH revealed a pattern similar to that of unimodal water-breathing fish. In deep aquatic hypoxia (water P-O2=1 kPa) the jeju increased the frequency of air breathing (f(AB)) tenfold and maintained M-tO2 unchanged from normoxia. This was associated with a significant increase in heart rate variability (HRV), each air breath (AB) being preceded by a brief bradycardia and then followed by a brief tachycardia. These f(H) changes are qualitatively similar to those associated with breathing in unimodal air-breathing vertebrates. Within 20 heartbeats after the AB, however, a beat-to-beat variability in f(H) typical of water-breathing fish was re-established. Pharmacological blockade revealed that both adrenergic and cholinergic tone increased simultaneously prior to each AB, and then decreased after it. However, modulation of inhibitory cholinergic tone was responsible for the major proportion of HRV, including the precise beat-to-beat modulation of f(H) around each AB. Pharmacological blockade of all variations in f(H) associated with air breathing in deep hypoxia did not, however, have a significant effect upon f(AB) or the regulation of M-tO2. Thus, the functional significance of the profound HRV during air breathing remains a mystery.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Human N-myc downstream-regulated gene 1 (NDRG1) is a metastasis suppressor gene with several potential functions, including cell differentiation, cell cycle regulation and response to hormones, nickel and stress. The purpose of this study was to investigate the immunoexpression of NDRG1 in oral and oropharyngeal squamous cell carcinomas searching for its role in the clinical course of these tumors. We investigated immunohistochemical expression of NDRG1 protein in 412 tissue microarray cores of tumor samples from 103 patients with oral and oropharyngeal squamous cell carcinomas and in 110 paraffin-embedded surgical margin sections. The results showed NDRG1 up-regulation in 101/103 (98.1 %) tumor samples, but no expression in any normal tissue sample. Western blot assays confirmed the immunohistochemical findings, suggesting that lower levels of NDRG1 are associated with a high mortality rate. NDRG1 overexpression was related to long-term specific survival (HR = 0.38; p = 0.009), whereas the presence of lymph-node metastasis showed the opposite association with survival (HR = 2.45; p = 0.013). Our findings reinforce the idea that NDRG1 plays a metastasis suppressor role in oral and oropharyngeal squamous cell carcinomas and may be a useful marker for these tumors.

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BACKGROUND: Inflammatory lung diseases are a major morbidity factor in children. Therefore, novel strategies for early detection of inflammatory lung diseases are of high interest. Bacterial lipopolysaccharide (LPS) is recognized via Toll-like receptors and CD14. CD14 exists as a soluble (sCD14) and membrane-associated (mCD14) protein, present on the surface of leukocytes. Previous studies suggest sCD14 as potential marker for inflammatory diseases, but their potential role in pediatric lung diseases remained elusive. Therefore, we examined the expression, regulation and significance of sCD14 and mCD14 in pediatric lung diseases. METHODS: sCD14 levels were quantified in serum and bronchoalveolar lavage fluid (BALF) of children with infective (pneumonia, cystic fibrosis, CF) and non-infective (asthma) inflammatory lung diseases and healthy control subjects by ELISA. Membrane CD14 expression levels on monocytes in peripheral blood and on alveolar macrophages in BALF were quantified by flow cytometry. In vitro studies were performed to investigate which factors regulate sCD14 release and mCD14 expression. RESULTS: sCD14 serum levels were specifically increased in serum of children with pneumonia compared to CF, asthma and control subjects. In vitro, CpG induced the release of sCD14 levels in a protease-independent manner, whereas LPS-mediated mCD14 shedding was prevented by serine protease inhibition. CONCLUSIONS: This study demonstrates for the first time the expression, regulation and clinical significance of soluble and membrane CD14 receptors in pediatric inflammatory lung diseases and suggests sCD14 as potential marker for pneumonia in children.

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Aim: To investigate the association of the Periodontal Risk Assessment (PRA) model categories with periodontitis recurrence and tooth loss during supportive periodontal therapy (SPT) and to explore the role of patient compliance. Material and Methods: In a retrospective cohort, PRA was performed for 160 patients after active periodontal therapy (APT) and after 9.5 ± 4.5 years of SPT. The recurrence of periodontitis and tooth loss were analysed according to the patient's risk profile (low, moderate or high) after APT and compliance with SPT. The association of risk factors with tooth loss and recurrence of periodontitis was investigated using logistic regression analysis. Results: In 18.2% of patients with a low-risk profile, in 42.2% of patients with a moderate-risk profile and in 49.2% of patients with a high-risk profile after APT, periodontitis recurred. During SPT, 1.61 ± 2.8 teeth/patient were lost. High-risk profile patients lost significantly more teeth (2.59 ± 3.9) than patients with moderate- (1.02 ± 1.8) or low-risk profiles (1.18 ± 1.9) (Kruskal–Wallis test, p=0.0229). Patients with erratic compliance lost significantly (Kruskal–Wallis test, p=0.0067) more teeth (3.11 ± 4.5) than patients compliant with SPT (1.07 ± 1.6). Conclusions: In multivariate logistic regression analysis, a high-risk patient profile according to the PRA model at the end of APT was associated with recurrence of periodontitis. Another significant factor for recurrence of periodontitis was an SPT duration of more than 10 years.

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AIM: To investigate the significance of the initial stability of dental implants for the establishment of osseointegration in an experimental capsule model for bone augmentation. MATERIAL AND METHODS: Sixteen male rats were used in the study. In each rat, muscle-periosteal flaps were elevated on the lateral aspect of the mandibular ramus on both sides, resulting in exposure of the bone surface. Small perforations were then produced in the ramus. A rigid, hemispherical Teflon capsule with a diameter of 6 mm and a height of 4 mm and with a hole in its middle portion, prepared to fit the circumference of an ITI HC titanium implant of 2.8 mm in diameter, was fixed to the ramus using 4 mini-screws. On one side of the jaw, the implant was placed through the hole in such a way that its apex did not make contact with the mandibular ramus (test). This placement of the implant did not ensure primary stability. On the other side of the jaw, a similar implant was placed through the hole of the capsule in such a way that contact was made between the implant and the surface of the ramus (control). This provided primary stability of the implant. After placement of the implants, the soft tissues were repositioned over the capsules and sutured. After 1, 3, 6 and 9 months, four animals were sacrificed and subjected to histometric analysis. RESULTS: The mean height of direct bone-to-implant contact of implants with primary stability was 38.8%, 52.9%, 64.6% and 81.3% of the implant length at 1, 3, 6 and 9 months, respectively. Of the bone adjacent to the implant surface, 28.1%, 28.9%, 52.6% and 69.6%, respectively, consisted of mineralized bone. At the test implants, no bone-to-implant contact was observed at any observation time or in any of these non-stabilized specimens. CONCLUSION: The findings of the present study indicate that primary implant stability is a prerequisite for successful osseointegration, and that implant instability results in fibrous encapsulation, thus confirming previously made clinical observations.

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The progression of hormone responsive to hormone refractory prostate cancer poses a major clinical challenge in the successful treatment of prostate cancer. The hormone refractory prostate cancer cells exhibit resistance not only to castrate levels of testosterone, but also to other therapeutic modalities and hence become lethal. Currently, there is no effective treatment available for managing this cancer. These observations underscore the urgency to investigate mechanism(s) that contribute to the progression of hormone-responsive to hormone-refractory prostate cancer and to target them for improved clinical outcomes. Tissue transglutaminase (TG2) is a multifunctional pro-inflammatory protein involved in diverse physiological processes such as inflammation, tissue repair, and wound healing. Its expression is also implicated in pathological conditions such as cancer and fibrosis. Interestingly, we found that the androgen-independent prostate cancer cell lines, which lacked androgen receptor (AR) expression, contained high basal levels of tissue transglutaminase. Inversely, the cell lines that expressed androgen receptor lacked transglutaminase expression. This attracted our attention to investigate the possible role this protein may play in the progression of prostate cancer, especially in view of recent observations that its expression is linked with increased invasion, metastasis, and drug resistance in multiple cancer cell types. The results we obtained were rather surprising and revealed that stable expression of tissue transglutaminase in androgen-sensitive LNCaP prostate cancer cells rendered these cells independent of androgen for growth and survival by silencing the AR expression. The AR silencing in TG2 expressing cells (TG2-infected LNCaP and PC-3 cells) was due to TG2-induced activation of the inflammatory nuclear transcription factor-kB (NF-kB). Thus, TG2 induced NF-kB was found to directly bind to the AR promoter. Importantly, TG2 protein was specifically recruited to the AR promoter in complex with the p65 subunit of NF-kB. Moreover, TG2 expressing LNCaP and PC-3 cells exhibited epithelial-to-mesenchymal transition, as evidenced by gain of mesenchymal (such as fibronectin, vimentin, etc.) and loss of epithelial markers (such as E-cadherin, b-catenin). Taken together, these results suggested a new function for TG2 and revealed a novel mechanism that is responsible for the progression of prostate cancer to the aggressive hormone-refractory phenotype.

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Background and purpose. Sialyl-Tn(STn) represents an aberrantly glycosylated mucin epitope which is expressed in breast cancer and other adenocarcinomas and is an important target for the development of novel immunotherapeutic approaches. It is a marker of adverse prognosis in colon and ovarian cancer, but information about its prognostic impact in breast cancer is limited. The primary aim of the present study was to investigate the influence of STn expression on outcome of invasive breast cancer in 207 women who received anthracyline-containing adjuvant chemotherapy in a prospective clinical trial.^ Methods. Expression of STn was determined by an immunohistochemical procedure using the B72.3 monoclonal antibody. The extent of staining was determined by two observers using a 0 through 4 point scale, with 0 representing $<$5% of cells staining; 1: 5-25%; 2: 26-50%; 3: 51-75%; and 4: $>$75%. Intraobserver and interobserver agreement was.78-.92 (kappa). Kaplan-Meier and Cox proportional regression survival analyses were used to compare STn-negative and STn-positive patients.^ Results. Forty-eight (23%) of the 207 specimens demonstrated positive staining of STn. With a median follow-up of five years, STn-positivity was associated with a higher 5-year recurrence-free survival time than STn-negativity (67% vs. 80%, respectively; p = 0.03). STn expression was significantly associated with menopausal status (p = 0.04) but not other conventional prognostic markers. The risk of breast cancer recurrence and death was assessed by multivariate Cox regression analyses with adjustment for lymph node status, tumor size, menopausal status, hormone receptor status, nuclear grade, S-phase fraction and ploidy. In the final multivariate model for recurrence-free survival, the three factors that showed prognostic significance were: lymph node status (hazard ratio (HR) 3.04, 95% confidence interval (CI) 1.08-8.49), STn expression (HR 2.02, 95% CI 1.09-3.73), and tumor size (HR 1.96, 95% CI 1.05-3.64). STn was also associated with worse overall survival (HR 2.16, 95% CI 0.95-4.92) in multivariate analysis.^ Conclusion. STn antigen was shown to be a predictor of poor outcome in breast cancer. This tumor-associated antigen may be a valuable marker for identifying individuals at high risk of developing recurrent disease who may benefit from adjuvant therapy targeted at STn following definitive local therapy. Further study is needed to clarify the biologic and prognostic role of STn in breast cancer. ^

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Objectives: The final goal in the successful treatment of schizophrenia patients is defined in improved functional recovery. Thus the integration of social cognitive tasks within a comprehensive treatment concept should offer significant advantages in generalization and transfer of therapy effects. Recent therapy outcome research supports these advantages. Empirical modeling identified social cognition as a mediating factor between neurocognition and functional recovery. Regarding this, we first developed the Integrated Psychological Therapy Program (IPT). It consists of 5 subprograms and combines interventions on neurocognition, social cognition, and social competence. As a further development of the cognitive part of IPT we developed the Integrated Neurocognitive Therapy (INT), which focuses on all social and neurocognitive domains defined by MATRICS. Methods: The aim was to investigate whether the application of the complete IPT is superior in comparison to the use of single IPT subprograms. Data were based on 37 independent IPT studies including a total sample of 1692 schizophrenia patients. Additionally, the proximal outcome in cognitive domains as well as in more distal outcome areas was investigated in an international RCT on INT including 169 schizophrenia outpatients. Results: All IPT subprogram variations obtained significant effects in proximal outcome. Each subprogram domain reached the largest effects in the targeted area. With regard to distal outcomes, combinations of subprograms showed a significant reduction of negative symptoms and an improvement in not targeted areas of functioning. This strongly supports vertical generalization effects to other functional domains. Regarding INT, results support efficacy compared to TAU in various cognitive domains, in psychosocial functioning and symptoms after therapy and at 1-year-follow-up. Conclusion: Results support evidence for the efficacy of longer lasting integrated therapy. The success of these treatment concepts is strongly based on successful therapy of social cognitive functions.

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AIMS To investigate the prognostic significance of macular capillary drop-out and previous panretinal laser photocoagulation in diabetic macular oedema treated with intravitreal ranibizumab. METHODS Retrospective observational case series. Treatment-naive patients with diabetic macular oedema that had been treated with intravitreal ranibizumab as per the RESTORE study protocol for at least 12 months were included. Some patients (n=15) had previous panretinal laser photocoagulation. Best-corrected visual acuity and central retina thickness were recorded monthly. The foveal avascular zone and the perifoveal capillaries were quantitatively and qualitatively assessed on fluorescein angiography on two occasions during the observational period. RESULTS From the 46 eyes (46 patients) in this study, 13 (28%) had evidence of perifoveal capillary drop-out. Central retinal thickness was significantly thinner at baseline (p=0.02) and throughout the study period in these eyes compared with those with normal perifoveal capillaries. Both groups responded with a significant gain of best-corrected visual acuity to ranibizumab treatment (7.6±3.3 and 6.3±1.3 ETDRS letters, respectively). Eyes with previous panretinal laser photocoagulation displayed a comparable final outcome regarding function and morphology, requiring a similar intensity of intravitreal injections. CONCLUSIONS Perifoveal capillary drop-out did not limit the gain of visual acuity from intravitreal ranibizumab treatment. The reduction of central retina thickness was similar to that seen in eyes with normal perifoveal capillaries. Central retinal thickness in eyes with perifoveal capillary drop-out was generally reduced. However, this did not affect their benefit from treatment. Ranibizumab did not increase the amount of perifoveal capillary loss.