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1.
Sci Total Environ ; 715: 136817, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32040992

RESUMO

River restoration practice frequently employs conservative designs that create and maintain prescribed, static morphology. Such approaches ignore an emerging understanding of resilient river systems that typically adjust their morphology in response to hydrologic, vegetative and sediment supply changes. As such, using increased dynamism as a restoration design objective will arguably yield more diverse and productive habitats, better managed expectations, and more self-sustaining outcomes. Here, we answer the following question: does restoring lateral migration in a channelised river that was once a wandering gravel-bed river, result in more diverse in-channel geomorphology? We acquired pre- and post-restoration topographic surveys on a segment of the Allt Lorgy, Scotland to quantify morphodynamics and systematically map geomorphic units, using Geomorphic Unit Tool (GUT) software. GUT implements topographic definitions to discriminate between a taxonomy of fluvial landforms that have been developed from an extension of the River Styles framework, using 3-tiered hierarchy: (1) differentiation based on stage or elevation relative to channel; (2) classification of form based on shape (mound, bowl, trough, saddle, plane, wall); and (3) mapping geomorphic units based on attributes (e.g., position and orientation). Results showed restoration increased geomorphic unit diversity, with the Shannon Diversity Index increasing from 1.40 pre-restoration (2012) to 2.04 (2014) and 2.05 (2016) after restoration. Channel widening, due to bank erosion, caused aerial coverage of in-channel geomorphic units to increase 23% after restoration and 6% further in the two-years following restoration. Once bank protection was removed, allowing bank erosion yieled a local supply of sediment to enable the formation and maintenance of lateral and point bars, riffles and diagonal bar complexes, and instream wood created structurally-forced pools and riffles. The methodology used systematically quantifies how geomorphic unit diversity increases when a river is given back its freedom space. The framework allows for testing restoration design hypotheses in post-project appraisal.

2.
Cell Death Dis ; 5: e1246, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24853424

RESUMO

Hyperactivation of the Wingless-type (Wnt)/ß-catenin pathway promotes tumor initiation, tumor growth and metastasis in various tissues. Although there is evidence for the involvement of Wnt/ß-catenin pathway activation in salivary gland tumors, the precise mechanisms are unknown. Here we report for the first time that downregulation of the Wnt inhibitory factor 1 (WIF1) is a widespread event in salivary gland carcinoma ex-pleomorphic adenoma (CaExPA). We also show that WIF1 downregulation occurs in the CaExPA precursor lesion pleomorphic adenoma (PA) and indicates a higher risk of progression from benign to malignant tumor. Our results demonstrate that diverse mechanisms including WIF1 promoter hypermethylation and loss of heterozygosity contribute to WIF1 downregulation in human salivary gland tumors. In accordance with a crucial role in suppressing salivary gland tumor progression, WIF1 re-expression in salivary gland tumor cells inhibited cell proliferation, induced more differentiated phenotype and promoted cellular senescence, possibly through upregulation of tumor-suppressor genes, such as p53 and p21. Most importantly, WIF1 significantly diminished the number of salivary gland cancer stem cells and the anchorage-independent cell growth. Consistent with this observation, WIF1 caused a reduction in the expression of pluripotency and stemness markers (OCT4 and c-MYC), as well as adult stem cell self-renewal and multi-lineage differentiation markers, such as WNT3A, TCF4, c-KIT and MYB. Furthermore, WIF1 significantly increased the expression of microRNAs pri-let-7a and pri-miR-200c, negative regulators of stemness and cancer progression. In addition, we show that WIF1 functions as a positive regulator of miR-200c, leading to downregulation of BMI1, ZEB1 and ZEB2, with a consequent increase in downstream targets such as E-cadherin. Our study emphasizes the prognostic and therapeutic potential of WIF1 in human salivary gland CaExPA. Moreover, our findings demonstrate a novel mechanism by which WIF1 regulates cancer stemness and senescence, which might have major implications in the field of cancer biology.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenoma Pleomorfo/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma/metabolismo , Senescência Celular , Células-Tronco Neoplásicas/metabolismo , Proteínas Repressoras/metabolismo , Neoplasias das Glândulas Salivares/metabolismo , Via de Sinalização Wnt , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenoma Pleomorfo/genética , Adenoma Pleomorfo/patologia , Biomarcadores Tumorais/genética , Carcinoma/genética , Carcinoma/patologia , Pontos de Checagem do Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA , Progressão da Doença , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Perda de Heterozigosidade , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/patologia , Regiões Promotoras Genéticas , Proteínas Repressoras/genética , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/patologia , Fatores de Tempo , Transfecção
3.
Theriogenology ; 79(1): 81-6, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23102849

RESUMO

Spermatozoa tend to swim near surfaces. Such attraction toward surface vicinity was approximated by the force-dipole theoretical approach and hydrodynamic modeling, but the physical parameters of surfaces have not usually been included in these models and their effect on sperm mobility remains unknown. In spermatozoa, changes in wave parameters, together with rotation around their longitudinal axis and circling appear when movement takes place close to surfaces. Here we show, by analysis of microscopy images (including high-speed video), a strong influence of the liquid-solid interface on sterlet spermatozoa motility characteristics compared with motility near the liquid-gas interface. Sperm cells swam at 16% lower velocity near a liquid-solid interface, rotating at a stable frequency of 25 Hz, each 180° rotation corresponding to one beat cycle and circling clockwise (when observed from top). In case of spermatozoa close to a water-air interface, rotation and circling were sporadic and irregular. Sterlet spermatozoa movement near a surface affects their velocity and possibly causes rotation. These behaviors are highly dependent on the level of suppleness of the interface, as has been previously predicted by modeling. Our results enhance the understanding of how surfaces influence fish spermatozoa motility. These insights on the effects of surfaces on fish spermatozoa motility imply that widely used methods rating sperm motility, such as computer-assisted sperm analysis, might lead to erroneous results. Further study of sperm motility near surfaces is urgently needed to correct our rating methods and better understand sperm behavior in natural conditions. Improved evaluation of sperm motility behavior near surfaces could be used to determine physical properties of aquatic interfaces with various surfaces composed of different materials.


Assuntos
Peixes/fisiologia , Motilidade dos Espermatozoides/fisiologia , Animais , Meio Ambiente , Masculino , Modelos Biológicos , Movimento/fisiologia , Rotação , Análise do Sêmen/veterinária , Cauda do Espermatozoide/fisiologia , Espermatozoides/fisiologia , Propriedades de Superfície , Natação
4.
Anaesth Intensive Care ; 40(2): 340-3, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22417031

RESUMO

Sugammadex is known to rapidly and completely reverse the effects of amino-steroidal neuromuscular blocking agents. However, the high costs of sugammadex have so far prevented its introduction as the standard reversal agent in most healthcare systems. At the Royal Perth Hospital, sugammadex was recently introduced as an unrestricted alternative to neostigmine for the reversal of amino-steroidal neuromuscular blocking agents. The aim of this retrospective observational audit was to investigate the impact of this change on clinical practice and associated healthcare costs. Data from all patients intubated during a one-month period in April to May 2010 and for a similar period in 2011 were retrospectively collected and the use of neuromuscular blocking agents and reversal agents were identified and the associated costs were calculated. More steroidal neuromuscular blocking agents and sugammadex (+743%), but less glycopyrrolate and neostigmine (-48%) were used in 2011. Using the manufacturer's list price, muscle relaxation and reversal costs increased from about A$42 per case to about A$127 per case. Between the investigated time periods no differences were found for anaesthesia time, operating time or time spent in the post anaesthesia care unit. However, there was a statistically significant decrease in the time between surgery and discharge (median 2.0 vs 2.2 days). While the design of the audit was such that no inferences can be made about the cause of this change, this is an interesting observation worthy of further investigation.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Bloqueio Neuromuscular/economia , Bloqueio Neuromuscular/estatística & dados numéricos , Bloqueadores Neuromusculares/antagonistas & inibidores , gama-Ciclodextrinas/economia , gama-Ciclodextrinas/uso terapêutico , Adulto , Idoso , Período de Recuperação da Anestesia , Cuidados Críticos/estatística & dados numéricos , Uso de Medicamentos , Feminino , Humanos , Tempo de Internação , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Fármacos Neuromusculares Despolarizantes , Fármacos Neuromusculares não Despolarizantes , Assistência Perioperatória/economia , Assistência Perioperatória/estatística & dados numéricos , Estudos Retrospectivos , Sugammadex
5.
Can J Appl Physiol ; 26(6): 527-42, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11842271

RESUMO

This study investigated the effect of creatine monohydrate (Cr) supplementation on performance and training volume in rowers. Twenty-two rowers trained with continuous and interval rowing and resistance training 4 and 2 days/week, respectively, for 6 weeks. Cr supplementation consisted of a 5-day load (0.3 g/kg(-1) x day(-1)) followed by a 5-week maintenance dose (0.03 g/kg(-1) x day(-1)) while training. Five days of Cr loading did not change body composition, repeated interval rowing performance, 2,000-m rowing times, or strength performance. Five additional weeks of training with a maintenance dose of Cr or placebo significantly improved body composition, VO2max, 2,000-m rowing times, repeated power interval performance, and strength to a similar extent in both groups. Subjects training with Cr did not perform more repetitions per set of strength exercise nor produce or maintain higher power outputs during repeated rowing sessions. Cr supplementation did not increase performance or training volume over a placebo condition in rowers that performed a combined high intensity rowing and strength program.


Assuntos
Creatina/farmacologia , Suplementos Nutricionais , Exercício Físico , Esportes , Adulto , Composição Corporal , Creatina/administração & dosagem , Feminino , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Consumo de Oxigênio , Resistência Física/efeitos dos fármacos , Estudos Prospectivos , Análise e Desempenho de Tarefas
6.
Otolaryngol Head Neck Surg ; 122(2): 195-200, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10652389

RESUMO

Squamous cell carcinomas were evaluated with respect to tumor differentiation (through use of hematoxylin and eosin stain), microvessel density (through use of CD-34 immunocytochemical stain), and magnitudes of malate dehydrogenase (MDH), hexokinase, and lactate dehydrogenase (LDH) enzyme activities. Direct correlations were found between tumor grade, MDH activity, and microvessel density. Direct correlations were also found between hexokinase activity and MDH activity and microvessel density. Inverse correlations were found between LDH activity and both tumor grade and MDH activity. These results suggest that the high rate of glucose utilization (indicated by hexokinase activity) found in more poorly differentiated tumors has a higher component of aerobic oxidative metabolism (indicated by MDH activity) and a relatively lower contribution from anaerobic metabolism (indicated by LDH activity) than do the rates found in more differentiated tumors. It is also suggested that as the glycolytic rate increases, more pyruvate goes into the Krebs cycle than into lactate. The availability of glucose-derived pyruvate for oxidative metabolism would mean less of a dependency on glutamine as a carbon source in squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Hexoquinase/metabolismo , L-Lactato Desidrogenase/metabolismo , Malato Desidrogenase/metabolismo , Neoplasias Otorrinolaringológicas/enzimologia , Neoplasias Otorrinolaringológicas/patologia , Carcinoma de Células Escamosas/irrigação sanguínea , Humanos , Microcirculação/patologia , Neoplasias Otorrinolaringológicas/irrigação sanguínea
7.
Adv Anat Pathol ; 6(6): 317-23, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10562893

RESUMO

The sinonasal undifferentiated carcinoma (SNUC) is an aggressive and rare neoplasm arising in the nasal cavity and the paranasal sinuses. To date, over 50 cases of histologically proven SNUCs have been reported since its original description in 1986. Presenting symptoms include facial pain, nasal obstruction, diplopia, epistaxis, proptosis, and periorbital swelling. The histologic features of this neoplasm include cohesive cells arranged in nests, ribbons, and trabeculae. The cells exhibit hyperchromatic nuclei and a high nuclear to cytoplasmic ratio. A brisk mitotic rate, tumor necrosis, and vascular invasion are prominent features. Confirming the diagnosis of SNUC at the light microscopic level can be challenging, since the microscopic differential diagnosis includes olfactory neuroblastoma, rhabdomyosarcoma, undifferentiated nasopharyngeal carcinoma (lymphoepithelioma), malignant lymphoma, malignant melanoma, and neuroendocrine (small cell undifferentiated; oat cell) carcinoma. Sinonasal undifferentiated carcinoma can be differentiated from these other neoplasms by correlating clinical, light microscopic, histochemical, immunohistochemical, and ultrastructural characteristics. Aggressive, multimodal therapy can provide the best opportunity for local control of this neoplastic process, but the optimal treatment has yet to be determined.


Assuntos
Neoplasias dos Seios Paranasais/patologia , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Neoplasias dos Seios Paranasais/classificação , Neoplasias dos Seios Paranasais/fisiopatologia , Neoplasias dos Seios Paranasais/terapia
8.
Otolaryngol Clin North Am ; 31(5): 759-71, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9735105

RESUMO

Histologic evaluations of neck dissection specimens from carcinomas of the head and neck provide information required for disease staging, planning further treatment, and prognosis. Histologic evaluation performed adequately and accurately can and continues to provide a more accurate, meaningful, and promising means of formulating and predicting prognosis including risk of metastases. A multi-institutional study using comprehensive standardized histologic evaluation of histopathologic variables of primary tumor and cervical lymph nodes among homogenous patient groups receiving similar therapy is important. Histopathologic parameters remain an important adjunct parameter to clinical evaluation in guiding, planning treatment, and predicting prognosis for patients with head and neck cancers.


Assuntos
Carcinoma/patologia , Neoplasias de Cabeça e Pescoço/patologia , Excisão de Linfonodo , Linfonodos/patologia , Carcinoma/secundário , Carcinoma/cirurgia , Previsões , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Metástase Linfática/patologia , Pescoço , Estadiamento de Neoplasias , Planejamento de Assistência ao Paciente , Prognóstico , Fatores de Risco
9.
Ultrastruct Pathol ; 20(1): 89-99, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8789215

RESUMO

Multinucleated giant stromal cells (MGSC) have been described in a variety of lesions of various anatomical sites. They are generally believed to be derived from fibroblasts or myofibroblasts. Their size and bizarre appearance may lead to an erroneous interpretation of infiltrating malignant cells, but they are regarded as reactive in nature. MGSC also seem to participate in a neoplastic process and form a part of tumors called giant cell fibroblastomas (GCF). In GCF, multinucleated giant cells are sparsely scattered throughout the tumor, which is composed of loosely arranged spindle cells. Thus far, no tumor composed of MGSC entirely, to the best of the authors' knowledge, has been reported. This study involved an 80-year-old female with an omental tumor, which is believed to represent the first case of tumor of MGSC. The patient developed abdominal pain; a large abdominal tumor measuring 18 x 15 x 5 cm by computerized tomography was found located between the left lobe of the liver, the transverse colon, and the greater curvature of the stomach. Although the tumor was adherent to the above organs and infiltrating the omentum, it was resectable. Grossly, the tumor was highly vascular and the surface was shaggy with no recognizable capsule. The cut surfaces were red to tan with frequent cystic spaces containing bloody material. Microscopically, the tumor cells were large and multinucleated (2-6 nuclei) with prominent nucleoli. The cytoplasm was abundant and stained amphophilic. These tumor cells formed moderately cellular sheets filling the spaces between the varying sized vessels. There was prominent vascularity throughout the tumor. DNA study by image analysis revealed aneuploidy peaks. On immunohistochemistry, the tumor cells were strongly positive for vimentin, moderately positive for actin along the periphery of the cytoplasm, and negative for cytokeratin, EMA, myoglobin, S-100, CEA, Factor XIIIa, HMB-45, and HAM56 and KP-1. Ultrastructurally, the cytoplasm contained rich profiles of RER with scattered lysosomes. The cell borders were slightly irregular with occasional subplasmalemmal densities facing loosely arranged collagenous stroma. The light microscopic, immunohistochemical, and electron microscopic features of tumor cells were remarkably similar to MGSC. The tumor size and gross appearance suggested a malignancy, but it was a diploid tumor and the patient remains disease free 5 years after a complete resection.


Assuntos
Tumores de Células Gigantes/ultraestrutura , Células Gigantes/ultraestrutura , Omento/patologia , Neoplasias Peritoneais/ultraestrutura , Idoso , Idoso de 80 Anos ou mais , Feminino , Tumores de Células Gigantes/patologia , Células Gigantes/patologia , Humanos , Imuno-Histoquímica , Neoplasias Peritoneais/patologia
10.
Anaesth Intensive Care ; 21(5): 602-7, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8273882

RESUMO

The first 2000 incidents reported to the Australian Incident Monitoring Study were analysed with respect to the incidence and circumstances of problems with endotracheal intubation; 85 (4%) indicated difficulties with intubation. One third of these were emergency cases, one third involved an initially unassisted trainee and one fifth were outside normal working hours. Failure to predict a difficult intubation was reported in one third of the cases, with another quarter presenting serious difficulty despite preoperative prediction. Difficulties with ventilation were experienced in 1 in 7 of the 85 reports; there was one cardiac arrest, but no death. Endotracheal intubation was not achieved in one fifth of the cases. The commonest complications reported amongst the 85 incidents were oesophageal intubation (18 cases), arterial desaturation (15 cases), and reflux of gastric contents (7 cases). Emergency trans-tracheal airways were required in 5 cases. Obesity, limited neck mobility and mouth opening, and inadequate assistance together accounted for two thirds of all the contributing factors. The most successful intubation aid in this series was a gum elastic bougie. A capnograph contributed to management in 28% and a pulse oximeter in 12% of the cases in which they were used. The most serious desaturations were associated with accidental oesophageal intubation. These data suggest a lack of reliable preoperative assessment techniques and skills for the prediction of difficult intubations. They also suggest the need for a greater emphasis on ensuring that the necessary equipment is available, and on teaching and learning drills for difficult intubation and any associated difficulty with ventilation.


Assuntos
Acidentes/estatística & dados numéricos , Intubação Intratraqueal/efeitos adversos , Gestão de Riscos/métodos , Austrália/epidemiologia , Humanos , Incidência
11.
Arch Dis Child ; 69(2): 206-11, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8215522

RESUMO

This study was designed to compare the efficacy and safety of a new inhaled corticosteroid, fluticasone propionate at a total daily dose of 200 micrograms, with beclomethasone dipropionate 400 micrograms/day in childhood asthma. A total of 398 asthmatic children (aged 4-19 years) were randomised to receive either fluticasone propionate 200 micrograms daily or beclomethasone dipropionate 400 micrograms daily for six weeks inhaled via a spacer device from a metered dose inhaler. During the study the patients recorded morning and evening peak expiratory flow rate (PEFR), symptom scores, and use of beta 2 agonist rescue medication. In addition, clinic visit PEFR and forced expiratory volume in one second were measured. Safety was assessed by recording all adverse events and by performing routine biochemistry and haematology screens including plasma cortisol concentration before and after treatment. For the purposes of analysis the diary card data were grouped into three periods: week 3 (days 15-21), week 6 (days 36-42), and weeks 1-6 (days 1-42). The results showed no significant difference between treatments on most efficacy parameters. However, there were significant differences in changes from baseline in favour of fluticasone propionate for % predicted morning PEFR both at week 3 (fluticasone propionate 6.1%, beclomethasone dipropionate 3.9%) and at week 6 (fluticasone propionate 8.3%, beclomethasone dipropionate 5. 9%) and % predicted evening PEFR at week 6 (fluticasone propionate 7.3%, beclomethasone dipropionate 4.9% and over weeks 1-6 (fluticasone propionate 5.5%, beclomethasone dipropionate 3.6%. Comparison between groups showed that the group receiving fluticasone propionate had a lower % of days with symptom-free exercise at week 6 (fluticasone propionate 87%, beclomethasone dipropionate 81%) and % days without rescue medication at week 6 (fluticasone propionate 87%, beclomethasone dipropionate 80%) and over weeks 1-6 (fluticasone propionate 80%, beclomethasone dipropionate 73%). Except for a higher incidence of sore throat in the fluticasone propionate group, the two treatments did not differ with regard to safety. There was no evidence of adrenal suppression with either treatment. In conclusion, fluticasone propionate 200 microgram daily ws at least as effective and as well tolerated as beclomethasone dipropionate 400 microgram daily in childhood asthma.


Assuntos
Androstadienos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Asma/tratamento farmacológico , Beclometasona/administração & dosagem , Administração por Inalação , Adolescente , Asma/fisiopatologia , Criança , Pré-Escolar , Método Duplo-Cego , Esquema de Medicação , Sistemas de Liberação de Medicamentos , Feminino , Fluticasona , Humanos , Pulmão/fisiopatologia , Masculino , Nebulizadores e Vaporizadores , Pico do Fluxo Expiratório
13.
Anaesthesia ; 46(1): 36-7, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1996752

RESUMO

Peri-operative acute upper airway obstruction may be life-threatening. A case is reported of a child with severe adenotonsillar hypertrophy who developed acute upper airway obstruction after a routine surgical procedure and required emergency adenotonsillectomy. The importance of pre-operative assessment is stressed.


Assuntos
Adenoidectomia , Obstrução das Vias Respiratórias/cirurgia , Complicações Pós-Operatórias/cirurgia , Tonsilectomia , Doença Aguda , Tonsila Faríngea/patologia , Obstrução das Vias Respiratórias/etiologia , Pré-Escolar , Emergências , Humanos , Hipertrofia/complicações , Masculino , Tonsila Palatina/patologia
14.
Fam Pract ; 5(2): 116-21, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3391351

RESUMO

A survey of general practitioners and nurses working in the treatment room was carried out in a Scottish new town to determine present treatment room practices and how nurses and doctors saw treatment room nursing developing in the future. There was a general desire to extend the nurse's role in practical fields but disagreement between doctors and nurses over the extent to which nurses should take on diagnostic and therapeutic roles.


Assuntos
Atitude do Pessoal de Saúde , Enfermagem em Saúde Comunitária/normas , Competência Clínica , Medicina de Família e Comunidade , Processo de Enfermagem , Papel (figurativo) , Escócia , Inquéritos e Questionários
16.
Health Visit ; 56(9): 331-2, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6555181
17.
18.
Health Visit ; 53(10): 415, 1980 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6907208
19.
Health Visit ; 53(8): 334-6, 1980 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6901732
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