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1.
Reg Environ Change ; 21(2): 33, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776560

RESUMO

Wetlands are critically important for biodiversity and human wellbeing, but face a range of challenges. This is especially true in the Mediterranean region, where wetlands support endemic and threatened species and remain integral to human societies, but have been severely degraded in recent decades. Here, in order to raise awareness of future challenges and opportunities for Mediterranean wetlands, and to inform proactive research and management, we identified (a) 50 key issues that might affect Mediterranean wetlands between 2020 and 2050, and (b) 50 important research questions that, if answered, would have the greatest impact on the conservation of Mediterranean wetlands between 2020 and 2050. We gathered ideas through an online survey and review of recent literature. A diverse assessment panel prioritised ideas through an iterative, anonymised, Delphi-like process of scoring, voting and discussion. The prioritised issues included some that are already well known but likely to have a large impact on Mediterranean wetlands in the next 30 years (e.g. the accumulation of dams and reservoirs, plastic pollution and weak governance), and some that are currently overlooked in the context of Mediterranean wetlands (e.g. increasing desalination capacity and development of antimicrobial resistance). Questions largely focused on how best to carry out conservation interventions, or understanding the impacts of threats to inform conservation decision-making. This analysis will support research, policy and practice related to environmental conservation and sustainable development in the Mediterranean, and provides a model for similar analyses elsewhere in the world. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10113-020-01743-1.

2.
Chem Commun (Camb) ; 52(49): 7711-4, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27230941

RESUMO

The dehydrogenation and dechlorination of FeOEP-Cl on Cu(111) has been studied in detail by scanning tunneling microscopy. Although, it is not possible to follow the reaction of an individual molecule, the complete pathway of the reaction with 22 inequivalent intermediate states and the rates of the involved processes are revealed. This is achieved by combining the analysis of a large data set showing thousands of molecules in the different stages of the reaction with numerical simulations.

3.
J Neurol Surg A Cent Eur Neurosurg ; 77(1): 59-62, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26588253

RESUMO

Hypertrophic olivary degeneration (HOD) is a rare form of transsynaptic degeneration characterized by hypertrophy of the inferior olivary nucleus situated in the olivary body, part of the medulla oblongata, representing a major source of input to the cerebellum. HOD typically results from focal lesions interrupting connections from the inferior olive within the dentato-rubro-olivary pathway, a region also known as the triangle of Guillain-Mollaret (TGM) (red nucleus, inferior olivary nucleus, and contralateral dentate nucleus). Clinically, HOD presents classically as palatal tremor and can include dentatorubral tremor and/or ocular myoclonus. The pathologic changes associated with HOD feature radiologic changes with the inferior olivary nucleus appearing larger and increasing its T2-weighted signal intensity on magnetic resonance images. HOD is commonly managed with pharmacotherapy but may require surgical intervention in extreme cases. HOD has been found to develop as a consequence of any injury that disrupts the TGM pathways (e.g., pontine cavernoma).These findings highlight the critical importance of a thorough knowledge of TGM anatomy to avoid secondary HOD. We present a patient who developed HOD secondary to resection of a tectal plate cavernous malformation and review the literature with an emphasis on the current knowledge of this disorder.


Assuntos
Procedimentos Neurocirúrgicos/métodos , Núcleo Olivar/patologia , Núcleo Olivar/cirurgia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/cirurgia , Hemangioma Cavernoso do Sistema Nervoso Central/complicações , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Humanos , Hipertrofia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/cirurgia , Complicações Pós-Operatórias/patologia
4.
Chemphyschem ; 14(15): 3472-5, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24038896

RESUMO

To be or not to be chlorinated: When octaethylporphyrin iron(III) chloride (FeOEP-Cl) molecules are sublimated onto Cu(111) surfaces, two different molecular species are observed through scanning tunneling microscopy, showing either a protrusion or a depression at the center. In combination with van der Waals-corrected density functional calculations, our experiments reveal that one species corresponds to FeOEP-Cl molecules with the chlorine atom pointing away from the surface, whereas the other species has been dechlorinated.

5.
Water Sci Technol ; 66(3): 635-43, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22744696

RESUMO

Modelling the urban water balance enables the understanding of the interactions of water within an urban area and allows for better management of water resources. However, few models today provide a comprehensive overview of all water sources and uses. The objective of the current paper was to develop a user-friendly tool that quantifies and visualizes all water flows, losses and inefficiencies in urban environments. The Urban Water Flow Model was implemented in a spreadsheet and includes a water-savings application that computes the contributions of user-selected saving options to the overall water balance. The model was applied to the coastal town of Limassol, Cyprus, for the hydrologic years 2003/04-2008/09. Data were collected from the different authorities and hydrologic equations and estimations were added to complete the balance. Average precipitation was 363 mm/yr, amounting to 25.4 × 10(6)m(3)/yr, more than double the annual potable water supply to the town. Surface runoff constituted 29.6% of all outflows, while evapotranspiration from impervious areas was 21.6%. Possible potable water savings for 2008/09 were estimated at 5.3 × 10(3) m(3), which is 50% of the total potable water provided to the area. This saving would also result in a 6% reduction of surface runoff.


Assuntos
Cidades/estatística & dados numéricos , Modelos Teóricos , Movimentos da Água , Abastecimento de Água/estatística & dados numéricos , Chipre , Água Potável , Ciclo Hidrológico
6.
Beilstein J Nanotechnol ; 3: 207-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22496993

RESUMO

Measurements of the frequency shift versus distance in noncontact atomic force microscopy (NC-AFM) allow measurements of the force gradient between the oscillating tip and a surface (force-spectroscopy measurements). When nonconservative forces act between the tip apex and the surface the oscillation amplitude is damped. The dissipation is caused by bistabilities in the potential energy surface of the tip-sample system, and the process can be understood as a hysteresis of forces between approach and retraction of the tip. In this paper, we present the direct measurement of the whole hysteresis loop in force-spectroscopy curves at 77 K on the PTCDA/Ag/Si(111) √3 × âˆš3 surface by means of a tuning-fork-based NC-AFM with an oscillation amplitude smaller than the distance range of the hysteresis loop. The hysteresis effect is caused by the making and breaking of a bond between PTCDA molecules on the surface and a PTCDA molecule at the tip. The corresponding energy loss was determined to be 0.57 eV by evaluation of the force-distance curves upon approach and retraction. Furthermore, a second dissipation process was identified through the damping of the oscillation while the molecule on the tip is in contact with the surface. This dissipation process occurs mainly during the retraction of the tip. It reaches a maximum value of about 0.22 eV/cycle.

7.
Beilstein J Nanotechnol ; 3: 809-16, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23365793

RESUMO

We present an overview of experimental and numerical methods to determine the spring constant of a quartz tuning fork in qPlus configuration. The simple calculation for a rectangular cantilever is compared to the values obtained by the analysis of the thermal excitation and by the direct mechanical measurement of the force versus displacement. To elucidate the difference, numerical simulations were performed taking account of the real geometry including the glue that is used to mount the tuning fork.

8.
Int J Cancer ; 123(8): 1956-63, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18688857

RESUMO

Meningiomas are the second most common type of brain and CNS tumors by histology. Surgery and radiotherapy are main treatment options, but meningiomas may be impossible to adequately resect or may regrow after surgery. In spite of many experimental attempts, there is no generally accepted chemotherapeutic approach. We have studied in a series of meningiomas the expression of the Toll-like receptor 4 (TLR4), which apart from its major role as a key factor of the innate immune system, is believed to play a role in tumorigenesis. All meningiomas studied expressed TLR4 mRNA and protein at variable degree. Paclitaxel, a ligand of TLR4, exhibited a dose- and time-dependent growth suppression in both monolayer and spheroid meningioma cell cultures. The knockdown of TLR4 with siRNA in meningioma cell cultures abrogated the inhibitory effect of paclitaxel. The suppressive action of paclitaxel on meningioma cell growth was enhanced in the presence of fluvastatin or the mitogen-actvated protein kinase (ERK1/2) inhibitor PD98059. At least part of the growth suppressive effect was mediated by the induction of apoptosis in meningioma cells by paclitaxel alone or in combination with fluvastatin. In conclusion, our in vitro results suggest that paclitaxel alone or in combination with other inhibitors of cell growth (statins, MAPK inhibitors) could provide a potential tool for the treatment of TLR4 expressing meningiomas.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Meníngeas/tratamento farmacológico , Meningioma/tratamento farmacológico , Meningioma/metabolismo , Paclitaxel/farmacologia , Receptor 4 Toll-Like/biossíntese , Adulto , Idoso , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/administração & dosagem , Fluvastatina , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Imuno-Histoquímica , Indóis/administração & dosagem , Masculino , Neoplasias Meníngeas/imunologia , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/patologia , Meningioma/imunologia , Meningioma/patologia , Pessoa de Meia-Idade , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Paclitaxel/administração & dosagem , RNA Interferente Pequeno/genética , Esferoides Celulares , Receptor 4 Toll-Like/genética , Células Tumorais Cultivadas
9.
J Endocrinol ; 191(1): 249-61, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17065408

RESUMO

As for any solid tumour, pituitary adenoma expansion is dependent on neovascularization through angiogenesis. In this process, vascular endothelial growth factor (VEGF) and its receptors VEGFR-1, VEGFR-2 and neuropilin-1 (NRP-1) may play an outstanding role. The intention of this work was to study the expression/localization and possible function of VEGF receptors in pituitary adenomas. VEGF receptor mRNA and protein expression was studied by in situ hybridization, immunohistochemistry and RT-PCR in 6 normal human pituitaries, 39 human pituitary adenomas and 4 rodent pituitary adenoma cell lines. VEGFR-1 expressing somatotroph MtT-S cells were used as a model to study the role of VEGF on cell proliferation and to elucidate the underlying mechanism of action. In normal pituitaries, VEGFR-1 was detected in endocrine cells, whereas VEGFR-2 and NRP-1 were exclusively expressed in endothelial cells. In pituitary tumours, a heterogeneous VEGFR expression pattern was observed by IHC. VEGFR-1, VEGFR-2 and NRP-1 were detected in 24, 18 and 17 adenomas respectively. In the adenomas, VEGFR-1 was expressed in epithelial tumour cells and VEGFR-2/NRP-1 in vessel endothelial cells. Functional studies in VEGFR-1-positive MtT-S cells showed that the ligands of VEGFR-1 significantly stimulated cell proliferation. This effect was mediated through the phosphatidylinositol-3-kinase-signalling pathway and involves induction of cyclin D1 and Bcl-2. Based on our results, we speculate that the ligands of VEGF receptors, such as VEGF-A and placenta growth factor, not only play a role in angiogenesis in pituitary adenomas, but also affect the growth of pituitary tumour cells through VEGFR-1.


Assuntos
Adenoma/química , Hipófise/química , Neoplasias Hipofisárias/química , Receptores de Fatores de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adenoma/metabolismo , Adenoma/patologia , Adulto , Idoso , Animais , Anticorpos Monoclonais/farmacologia , Western Blotting/métodos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromonas/farmacologia , Células Endoteliais/química , Feminino , Humanos , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Ligantes , Masculino , Pessoa de Meia-Idade , Morfolinas/farmacologia , Neuropilina-1/genética , Inibidores de Fosfoinositídeo-3 Quinase , Hipófise/metabolismo , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Ratos , Receptores de Fatores de Crescimento do Endotélio Vascular/imunologia , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Somatotrofos/citologia , Somatotrofos/efeitos dos fármacos , Estimulação Química , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/análise , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
10.
J Neurooncol ; 68(2): 131-40, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15218949

RESUMO

The hematopoietic growth factors granulocyte- and granulocyte-macrophage colony stimulating factor (G-CSF and GM-CSF) are nowadays widely used in routine cancer therapies as potent factors to control radiation and chemotherapy induced neutropenia, a side effect that frequently endangers the success of tumor therapies. However, there is little information about the role of G-CSF and GM-CSF for tumor growth or progression. We were interested in the expression and potential role of both factors in human meningiomas, tumors of arachnoidal origin that account for about 20% of all primary intracranial tumors. Therefore, we analyzed immunohistochemically the protein expression of G-CSF, GM-CSF and their respective receptors in 30 meningioma tissues of different malignancy and histopathological type. Both factors and receptors were not expressed in the corresponding normal tissue. In contrast, G-CSF, GM-CSF and their receptors were expressed to a varying degree in human meningiomas. Increasing expression of both factors and receptors correlated significantly with enhanced proliferation in the tumor and thus with higher malignancy. In addition, a strong perivascular expression of G-CSF was associated with a highly vascularized tumor type. Thus, expression of both G-CSF and GM-CSF is associated with the expression of proliferation vascularization, two markers of an increasingly malignant tumor phenotype, suggesting a contribution of both factors to tumor progression.


Assuntos
Fator Estimulador de Colônias de Granulócitos/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Neoplasias Meníngeas/irrigação sanguínea , Neoplasias Meníngeas/patologia , Meningioma/irrigação sanguínea , Meningioma/patologia , Neovascularização Patológica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Divisão Celular , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Índice Mitótico
11.
Eur J Endocrinol ; 149(5): 455-61, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14585094

RESUMO

OBJECTIVE: Interleukin-6 (IL-6), a member of the gp130 cytokine family, is considered to be an important modulator of function and growth in endocrine anterior pituitary cells. In pituitary adenomas, where IL-6 is often produced by the tumour cells, it is thought to be involved in pituitary adenoma pathophysiology via autocrine/paracrine mechanisms. METHODS: We have studied in primary cell cultures of human somatotroph adenomas whether IL-6 stimulates growth hormone secretion and whether intratumoral IL-6 is affected by various IL-6-regulating factors. RESULTS: Interleukin-6 stimulated GH secretion in 10 out of 11 somatotroph adenoma cultures (1.4- to 6.5-fold above basal levels). In comparative studies the GH-stimulatory potency of IL-6 was identical, or even stronger, than that of GHRH. In eight out of 11 adenoma cell cultures, IL-6 production was observed. This suggests that GH production might be stimulated by IL-6 in an autocrine/paracrine manner in these tumours. Dexamethasone strongly inhibited basal IL-6 secretion in all IL-6-producing adenoma cell cultures, whereas the IL-6 inhibitory or stimulatory action of other factors (octreotide, transforming growth factor-beta1, insulin-like growth factor-I, pituitary adenylate cyclase-activating peptide and oestradiol) were heterogeneous in the different adenomas. Only transforming growth factor-alpha consistently stimulated IL-6 secretion in all of the adenomas studied. CONCLUSIONS: Intratumoral IL-6, which is differently regulated by various factors, might contribute to excessive GH production in the majority of somatotroph adenomas.


Assuntos
Adenoma/metabolismo , Interleucina-6/metabolismo , Neoplasias Hipofisárias/metabolismo , Adjuvantes Imunológicos/metabolismo , Adjuvantes Imunológicos/farmacologia , Adulto , Relação Dose-Resposta a Droga , Feminino , Hormônio do Crescimento Humano/metabolismo , Humanos , Técnicas In Vitro , Interleucina-6/farmacologia , Masculino , Pessoa de Meia-Idade , Células Tumorais Cultivadas
12.
Surg Neurol ; 58(3-4): 189-92; discussion 193, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12480212

RESUMO

BACKGROUND: Neurogenic arterial hypertension has been proposed to be caused by neurovascular compression in many cases. However, there is little reference to tumors causing hypertension by local compression of the vagal nerve or the ventrolateral medulla oblongata. The following case illustrates the effects of surgery for a meningioma of the foramen magnum on arterial hypertension. CASE DESCRIPTION: A 54-year-old woman suffered from arterial hypertension for at least 7 months, for which she required a combined medical treatment regime. She suffered for 6 months from dizziness and tinnitus, more in the left ear than in the right. Neurologic examination revealed a horizontal fixation nystagmus and a mild left-sided hearing loss. Magnetic resonance imaging and computed tomographic angiography showed a contrast-enhancing tumor on the left side of the foramen magnum compressing the medulla oblongata close to the vertebral artery and vascularized by branches of the left PICA. Complete surgical extirpation was performed using a medial craniocervical approach. The tinnitus and dizziness were gone and hearing improved. Postoperatively, the arterial hypertension showed a long-lasting improvement (observation period 8 months) with only minimal medical treatment. CONCLUSION: Based on our case, we conclude that tumors in close proximity to the ventrolateral medulla oblongata may induce neurogenic hypertension, similar to neurovascular compression.


Assuntos
Hipertensão/cirurgia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Angiografia Cerebral , Feminino , Seguimentos , Forame Magno/patologia , Forame Magno/cirurgia , Humanos , Hipertensão/etiologia , Imageamento por Ressonância Magnética , Bulbo/patologia , Bulbo/cirurgia , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico , Meningioma/complicações , Meningioma/diagnóstico , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/complicações , Síndromes de Compressão Nervosa/diagnóstico , Síndromes de Compressão Nervosa/cirurgia , Tomografia Computadorizada por Raios X , Doenças do Nervo Vago/complicações , Doenças do Nervo Vago/diagnóstico , Doenças do Nervo Vago/cirurgia
13.
Surg Neurol ; 57(1): 15-8; discussion 18-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11834263

RESUMO

BACKGROUND: Ventral perforation and vascular lesions are rare but life-threatening complications in lumbar disc surgery. In some cases, however, it remains unclear from the clinical situation whether a laparotomy is necessary to save the patient. The goal of this study is to demonstrate the value of spiral CT (computed tomography) angiography for emergency vascular diagnosis in two cases. METHODS: Spiral CT angiography with an intravenous bolus contrast medium injection and reconstruction with images in sagittal, coronal, and oblique planes was performed. RESULTS: Spiral CT angiography confirms or excludes a vascular lesion, as demonstrated in two case reports. CONCLUSION: In unclear cases when ventral perforation in lumbar disc surgery is suspected, the need for emergency laparotomy can be confirmed quickly by noninvasive spiral CT angiography.


Assuntos
Angiografia/métodos , Serviços Médicos de Emergência , Deslocamento do Disco Intervertebral/cirurgia , Complicações Intraoperatórias , Vértebras Lombares , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Vértebras Lombares/irrigação sanguínea , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Microcirurgia , Pessoa de Meia-Idade , Ruptura/diagnóstico por imagem , Ruptura/etiologia , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/cirurgia
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