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1.
Anaesthesia ; 75(1): 96-108, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31729019

RESUMO

Anaesthetists are thought to be at increased risk of suicide amongst the medical profession. The aims of the following guidelines are: increase awareness of suicide and associated vulnerabilities, risk factors and precipitants; to emphasise safe ways to respond to individuals in distress, both for them and for colleagues working alongside them; and to support individuals, departments and organisations in coping with a suicide.


Assuntos
Anestesistas/psicologia , Anestesistas/estatística & dados numéricos , Transtornos Mentais/diagnóstico , Estresse Psicológico/diagnóstico , Suicídio/prevenção & controle , Suicídio/psicologia , Guias como Assunto , Humanos , Transtornos Mentais/complicações , Transtornos Mentais/psicologia , Fatores de Risco , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , Suicídio/estatística & dados numéricos , Reino Unido
2.
Hand Surg Rehabil ; 38(5): 298-301, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31404681

RESUMO

Surgical results for treatment of medial epicondylitis and cubital tunnel syndrome are generally satisfactory when performed alone. However, our experience suggests a combined procedure is associated with inferior outcomes. A retrospective review was conducted of consecutive surgical cases of medial epicondylectomy/debridement and ulnar nerve decompression during a single operation at our institution from March 2008 to February 2017 using CPT codes. Thirty combined procedures were identified in 29 patients. Fourteen patients and 15 elbows returned to clinic for evaluation at average 4.3 years after surgery (8 men, 6 women, mean age 45.1 years). A Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire, visual analogue pain scale (VAS), and physical examination were performed. The data was stratified by type of ulnar nerve procedure and analyzed. Three of fifteen elbows underwent in situ ulnar nerve decompression, and twelve of 15 had transposition, five subcutaneous and seven submuscular. The mean DASH score for in situ decompression was significantly higher than that of transposition (68.2 vs. 13.1). The average visual pain score for patients whom underwent in situ decompression was significantly higher than that of those with ulnar nerve transposition (8.0 vs. 1.2). All other physical exam measures demonstrated no significant difference between the two groups. In situ ulnar nerve decompression in the setting of medial epicondylectomy/debridement may be associated with inferior clinical outcomes in comparison to ulnar nerve transposition. Further studies are needed to validate the results of our study and inform management.

3.
Dalton Trans ; 46(17): 5702-5710, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28266666

RESUMO

The ligand 1,1'-bis(diphenylphosphino)ferrocene (dppf) is commonly employed in a variety of catalytic systems. There are a variety of coordination modes known for dppf, the least studied being the κ3 coordination mode, in which both phosphorus atoms and the iron atom of dppf interact with another metal center. One such compound is the previously reported [Pd(κ3-dppf)(PPh3)]2+. A series of related compounds, [Pd(κ3-dppf)(P(p-C6H4R)3)]2+ (R = OCH3, CH3, F and CF3), has been synthesized and characterized. The X-ray crystal structure of [Pd(dppf)(P(p-C6H4F)3)][BF4]2 was determined. Electrochemical and computational studies indicate that the electron donor ability of the P(p-C6H4R)3 ligands influences the properties of these compounds. Substitution reactions of the P(p-C6H4R)3 ligands have been examined, and, in general, the more electron donating P(p-C6H4R)3 ligands completely replace the less electron donating ones. The kinetics of the reaction of [Pd(κ3-dppf)(P(p-C6H4F)3)]2+ with P(p-C6H4OCH3)3 indicate that the reaction proceeds through a dissociative mechanism, contrary to the associative substitutions prevalent in square planar palladium(ii) chemistry.

4.
Anaesthesia ; 71(10): 1153-62, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27611038

RESUMO

Paracetamol is a commonly used drug in the intensive care unit. There have been reports in the literature of an association with significant hypotension, a potentially important interaction for labile critically ill patients. Route of administration may influence the incidence of hypotension. This single-centre, prospective, open-label, randomised, parallel-arm, active-control trial was designed to determine the incidence of hypotension following the administration of paracetamol to critically ill patients. Fifty adult patients receiving paracetamol for analgesia or pyrexia were randomly assigned to receive either the parenteral or enteral formulation of the drug. Paracetamol concentrations were measured at baseline and at multiple time points over 24 h. The maximal plasma paracetamol concentration was significantly different between routes; 156 vs. 73 micromol.l(-1) [p = 0.0005] following the first dose of parenteral or enteral paracetamol, respectively. Sixteen hypotensive events occurred in 12 patients: parenteral n = 12; enteral n = 4. The incident rate ratio for parenteral vs. enteral paracetamol was 2.94 (95% CI 0.97-8.92; p = 0.06). The incidence of hypotension associated with paracetamol administration is higher than previously reported and tends to be more frequent with parenteral paracetamol.


Assuntos
Acetaminofen/farmacologia , Analgésicos não Entorpecentes/farmacologia , Cuidados Críticos/métodos , Hemodinâmica/efeitos dos fármacos , Hipotensão/induzido quimicamente , Infusões Parenterais/métodos , Acetaminofen/administração & dosagem , Acetaminofen/efeitos adversos , Idoso , Analgésicos não Entorpecentes/administração & dosagem , Analgésicos não Entorpecentes/efeitos adversos , Estado Terminal , Vias de Administração de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
5.
Br J Cancer ; 112(12): 1888-94, 2015 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-25989278

RESUMO

BACKGROUND: Metastatic colorectal cancer (mCRC) that harbours a BRAF V600E mutation (BRAF MT) is associated with poorer outcomes. However, whether this mutation is predictive of treatment benefit from anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) is uncertain. METHODS: We conducted a systematic review and meta-analysis of randomised controlled trials (RCTs) published up to July 2014 that evaluated the effect of BRAF MT on the treatment benefit from anti-EGFR mAbs for mCRC. RESULTS: Seven RCTs met the inclusion criteria for assessment of overall survival (OS), whereas eight RCTs met the inclusion criteria for assessment of progression-free survival (PFS). For RAS WT/BRAF MT tumours, the hazard ratio for OS benefit with anti-EGFR mAbs was 0.97 (95% CI; 0.67-1.41), whereas the hazard ratio was 0.81 (95% CI; 0.70-0.95) for RAS WT/BRAF WT tumours. However, the test of interaction (P=0.43) was not statistically significant, highlighting that the observed differences in the effect of anti-EGFR mAbs on OS according to the BRAF mutation status may be due to chance alone. Regarding PFS benefit with anti-EGFR mAbs, the hazard ratio was 0.86 (95% CI; 0.61-1.21) for RAS WT/BRAF MT tumours as compared with 0.62 (95% CI; 0.50-0.77) for RAS WT/BRAF WT tumours (test of interaction, P=0.07). INTERPRETATION: This meta-analysis demonstrates that there is insufficient evidence to definitively state that RAS WT/BRAF MT individuals attain a different treatment benefit from anti-EGFR mAbs for mCRC compared with RAS WT/BRAF WT individuals. As such, there are insufficient data to justify the exclusion of anti-EGFR mAb therapy for patients with RAS WT/BRAF MT mCRC.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Receptores ErbB/antagonistas & inibidores , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Anticorpos Monoclonais/uso terapêutico , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Humanos , Metástase Neoplásica , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Niger J Clin Pract ; 18(4): 569-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25966735

RESUMO

Five cases of machete cut injuries to the maxillofacial region seen over a period of 8 months (January-September, 2012), at the Maxillofacial Unit of Ahmadu Bello University Teaching Hospital, Zaria, Nigeria, are presented. The severity of the injuries is evident from the extent of tissue disruption as shown in the pictures. The immediate threats to life in the cases were hemorrhage and airway obstruction. Surgical repairs were performed under local anesthetic infiltration in three cases while the rest were performed under general anesthesia. There was no nerve repair done due to lack of facilities, although, adequate apposition of soft and hard tissues were achieved. Four patients had rapid postoperative recovery in our facility while one absconded after wound debridement and repair was achieved. Two patients who had nerve injuries were followed-up to monitor recovery of the injured nerves. There was no tetanus, gangrene, pseudoaneurysm or death recorded in our cases. There is a need for relevant authorities to check the occurrence of this kind of injury, especially as the weapon used is a house-hold tool, which is readily available and accessible to all and sundry.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Traumatismos Maxilofaciais/epidemiologia , Violência/estatística & dados numéricos , Ferimentos Penetrantes/epidemiologia , Adulto , Humanos , Incidência , Masculino , Traumatismos Maxilofaciais/etiologia , Nigéria/epidemiologia , Ferimentos Penetrantes/etiologia , Adulto Jovem
7.
Ann Oncol ; 26(1): 13-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25115304

RESUMO

BACKGROUND: Monoclonal antibodies (mAbs) targeting the epidermal growth factor receptor (EGFR) prolong survival in metastatic colorectal cancer (mCRC) Kirsten rat sarcoma viral oncogene (KRAS) exon 2 wild-type tumors. Recent evidence has suggested that other RAS mutations (in exons 3 and 4 of KRAS and exons 2, 3 and 4 of a related gene, NRAS) may also be predictive of resistance. METHODS: Systematic review and meta-analysis of randomized, controlled trials (RCTs) evaluating anti-EGFR mAbs that have assessed tumors for new RAS mutations. Tumors with the new RAS mutations were compared with both tumors without any RAS mutations and tumors with KRAS exon 2 mutations with respect to anti-EGFR treatment progression-free survival (PFS) and overall survival (OS) benefit. RESULTS: Nine RCTs comprising a total of 5948 participants evaluated for both KRAS exon 2 and new RAS mutations met the inclusion criteria. Approximately 20% of KRAS exon 2 wild-type tumors harbored one of the new RAS mutations. Tumors without any RAS mutations (either KRAS exon 2 or new RAS mutations) were found to have significantly superior anti-EGFR mAb PFS (P < 0.001) and OS (P = 0.008) treatment effect compared with tumors with any of the new RAS mutations. No difference in PFS or OS benefit was evident between tumors with KRAS exon 2 mutations and tumors with the new RAS mutations. Results were consistent between different anti-EGFR agents, lines of therapy and chemotherapy partners. Anti-EGFR mAb therapy significantly improved both PFS {hazard ratio 0.62 [95% confidence interval (CI) 0.50-0.76]} and OS [hazard ratio 0.87 (95% CI 0.77-0.99)] for tumors without any RAS mutations. No PFS or OS benefit was evident with use of anti-EGFR mAbs for tumors harboring any RAS mutation (P > 0.05). CONCLUSION: Tumors harboring one of the new RAS mutations are unlikely to significantly benefit from anti-EGFR mAb therapy in mCRC.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Receptores ErbB/antagonistas & inibidores , GTP Fosfo-Hidrolases/genética , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Cetuximab , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/imunologia , Humanos , Panitumumabe , Proteínas Proto-Oncogênicas p21(ras)
8.
Drug Metab Dispos ; 40(11): 2119-25, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22863683

RESUMO

Cytochromes P450 (P450s) contribute to the metabolic activation and inactivation of various endogenous substrates. Despite years of research, the physiological role of CYP2S1 remains unknown. CYP2S1 has demonstrated NADPH P450-reductase-independent metabolism of cyclooxygenase (COX)-derived prostaglandins [e.g., prostaglandin G(2) (PGG(2))] at nanomolar concentrations. Arachidonic acid is converted to prostaglandin precursors [PGG(2) and prostaglandin H(2) (PGH(2))] through COX. These precursors are used to synthesize numerous prostanoids, including PGE(2). Prostaglandin E(2) (PGE(2)) promotes cell proliferation and cell migration and inhibits apoptosis. CYP2S1 metabolism of PGG(2) presumably sequesters PGG(2) and PGH(2), making them unavailable for synthesis of prostanoids such as PGE(2). Whether CYP2S1 contributes to prostaglandin metabolism and influences cell physiological remains to be determined. The purpose of this study was to evaluate the physiological role of CYP2S1, if any, in human bronchial epithelial cells [SV40-derived bronchial epithelial cell line (BEAS-2B)]. To do this, we used small interfering RNA to deplete CYP2S1 mRNA and protein by approximately 75% and evaluated the impact of CYP2S1 depletion on cell proliferation and migration. CYP2S1 depletion enhanced both cell proliferation and migration in BEAS-2B cells. Consistent with the proposed role of CYP2S1 in PGE(2) synthesis, the reduction in CYP2S1 expression doubled intracellular PGE(2) levels. Pharmacological administration of PGE(2) enhanced cell proliferation in BEAS-2B cells but failed to promote migration. Our data reveal an important role for CYP2S1 in the regulation of cell proliferation and migration, occurring in part through modulation of prostaglandin synthesis.


Assuntos
Brônquios/metabolismo , Movimento Celular/fisiologia , Sistema Enzimático do Citocromo P-450/metabolismo , Dinoprostona/biossíntese , Mucosa Respiratória/metabolismo , Processos de Crescimento Celular/fisiologia , Linhagem Celular , Sistema Enzimático do Citocromo P-450/deficiência , Sistema Enzimático do Citocromo P-450/genética , Dinoprostona/genética , Dinoprostona/metabolismo , Células Epiteliais/citologia , Células Epiteliais/enzimologia , Células Epiteliais/metabolismo , Humanos , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Mucosa Respiratória/citologia , Mucosa Respiratória/enzimologia
9.
Sci Total Environ ; 434: 171-85, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22417883

RESUMO

An assessment is made of the role of riverine colloids in macronutrient (nitrogen, phosphorus and carbon), metal and trace element partitioning and transport, for five rivers in the Ribble and Wyre catchments in north-western England, under baseflow/near-baseflow conditions. Cross-flow ultrafiltration was used to separate colloidal (<0.45 µm >1 kDa) and truly dissolved (<1 kDa) fractions from river water. Clear patterns were observed, along the upland-lowland land use continuum, in the partitioning and transport of macronutrients and metals between the colloidal, truly dissolved and acid-available particulate (>0.45 µm, suspended) fractions. Of these operationally-defined fractions measured, colloids were generally more important for both macronutrient and metal transport in the upland than in the lowland rivers. The results suggest that organic moieties in truly dissolved form from sewage effluent may have a greater capacity to chelate metals. Organic-rich colloids in the upland moorlands and metal oxide colloidal precipitates in the industrial rivers had a higher capacity for binding metals than the colloidal fractions in the urban and agricultural lowland rivers. Aggregation of these colloids may provide an important mechanism for formation of larger suspended particulates, accounting for a higher degree of metal enrichment in the acid-available particulate fractions of the upland moorland and lowland industrial rivers, than in the lowland agricultural and urban rivers. This mechanism of transfer of contaminants to larger aggregates via colloidal intermediates, known as 'colloidal pumping' may also provide a mechanism for particulate P formation and the high proportion of P being transported in the particulate fraction in the uplands. The cross-flow ultrafiltration data also allowed refinement of partition coefficients, by accounting for colloids within the solids phase and replacing the filtered (<0.45 µm) fraction with the truly dissolved (<1 kDa) concentrations. These provided a clearer description of the controls on metal and P partitioning along the upland-lowland continuum.

10.
J Environ Monit ; 14(1): 155-64, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22130567

RESUMO

The concentrations of manganese (Mn) in the Upper River Severn (the Plynlimon catchments) are examined in relation to rainfall, cloud water, throughfall, stemflow and stream water concentrations where there is over 20 years of monitoring data available. Manganese concentrations are particularly low in rainfall and cloud water, with maximum concentrations occurring under low volumes of catch due to atmospheric "washout" of contaminants and dry deposition. There is strong Mn enrichment in throughfall and stemflow and this is probably linked to cycling through the vegetation. Manganese in the streams and groundwaters are primarily supplied from within-catchment sources. The highest concentrations occur within the tree canopy probably due to element cycling and in groundwaters due to mobilisation from the rock. Manganese concentrations in streams are at their lowest during spring and summer following long dry spells, with rapid increases following subsequent rain. There is no clear long-term trend in Mn concentration in the streams although there are increases in Mn concentrations for years when there is extensive felling of spruce plantation forest and in 1995 following a more extensive dry period. New high resolution monitoring picks up the effects of the rising limb of the hydrograph when concentrations rapidly increase, diurnal patterns during summer low-flow periods and contrasting dynamics between moorland and forested catchments.


Assuntos
Monitoramento Ambiental , Manganês/análise , Rios/química , Poluentes Químicos da Água/análise , Atmosfera/química , Agricultura Florestal/estatística & dados numéricos , Água Subterrânea/química , Cinética , Modelos Lineares , País de Gales , Poluição Química da Água/estatística & dados numéricos , Tempo (Meteorologia)
11.
Phys Chem Chem Phys ; 13(18): 8441-7, 2011 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21359358

RESUMO

The production of a translationally cold (T < 1 K) sample of bromine atoms with estimated densities of up to 10(8) cm(-3) using photodissociation is presented. A molecular beam of Br(2) seeded in Kr is photodissociated into Br + Br* fragments, and the velocity distribution of the atomic fragments is determined using (2 + 1) REMPI and velocity map ion imaging. By recording images with varying delay times between the dissociation and probe lasers, we investigate the length of time after dissociation for which atoms remain in the laser focus, and determine the velocity spread of those atoms. By careful selection of the photolysis energy, it is found that a fraction of the atoms can be detected for delay times in excess of 100 µs. These are atoms for which the fragment recoil velocity vector is directly opposed and equal in magnitude to the parent beam velocity leading to a resultant lab frame velocity of approximately zero. The FWHM velocity spreads of detected atoms along the beam axis after 100 µs are less than 5 ms(-1), corresponding to temperatures in the milliKelvin range, opening the possibility that this technique could be utilized as a slow Br atom source.

12.
J Environ Monit ; 13(5): 1255-63, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21442109

RESUMO

Ten years of monitoring of rainfall and streams in the remote acidic and acid sensitive moorland and afforested moorland of upland mid-Wales reveals concentrations of arsenic (As) typically <1 µg L(-1). On average, the lowest concentrations occur within rainfall and they have declined over time probably in response to reductions in global emissions. There is a corresponding reduction within the streams except for forested systems where concentrations up to doubled following clear-fell. Within the streams there are both annual cycling and diurnal cycling of As. The annual cycling gives maxima during the summer months and this probably reflects the importance of groundwater inputs and mineralisation/desorption from the surface soil layers. Correspondingly, the diurnal cycling occurs during the summer months at low flow periods with As concentrations highest in the afternoon/evening. For the urban/industrial basins of northern England with historically a much higher As deposition, land contamination and effluent discharges, comparative data indicate As concentrations around three fold higher: strong seasonal patterns are observed for the same reasons as with the uplands. Across the sites, the As concentrations are over an order of magnitude lower than that of environmental concern. Nonetheless, the results clearly show the effects of declining emissions on rainfall deposition and some indication of areas of historic contamination. Arsenic is mainly present in the <0.45 fraction, but cross-flow filtration indicates that approx. 43% is in the colloidal phase at the clean water sites, and 16% in the colloidal phase at the contaminated sites. Part of this colloidal component may well be associated with organic carbon.


Assuntos
Arsênico/análise , Chuva/química , Rios/química , Poluentes Químicos da Água/análise , Cidades , Monitoramento Ambiental , Fenômenos Geológicos , Solo/química , Poluentes do Solo/análise , Reino Unido , Ciclo Hidrológico , Poluição Química da Água/estatística & dados numéricos
13.
J Environ Monit ; 12(12): 2299-306, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20967394

RESUMO

Total mercury (T-Hg) concentrations in rivers are described across a rural to urban/industrial and agricultural landscape gradient in NW England. T-Hg ranges between 0.2 and 230 ng L(-1). The regional median was 3.6 ng L(-1) with individual river medians ranging between 1.9 and 8.3 ng L(-1). Median T-Hg concentrations were sometimes moderately higher for the lowland areas and at higher flows. Our estimates suggest that the Ribble estuary receives 9.2 kg y(-1) and the Wyre estuary 0.7 kg y(-1). In order to examine regional inputs from urban/industrial components, regression analysis was undertaken by comparing three types of hydrochemical signature: suspended sediments (SS), which provide a measure of the particulate component, dissolved organic carbon (DOC) that provides an indication of humic/fulvic acids that are part of the organic colloids and strong chelating agents, and boron a marker of sewage effluents and population density. The results show high positive relationships of T-Hg with both SS and DOC, but no relationship with the urban/industrial signal. The regression analysis with T-Hg indicated on average a gradient of 0.33 ng mg(-1) for DOC and 0.2 ng mg(-1) for SS. They indicate the primary importance of a diffuse source of T-Hg. For the upland areas and cleaner river systems, the linkages between T-Hg and DOC were particularly strong, while for the lowland areas, the linkage with SS proved stronger. Analysis of a latter subset of data that partition the SS into organic and inorganic fractions indicated that the T-Hg was primarily linked with the organic fraction. Indeed, multiple regression of T-Hg with DOC and POM reveals gradients similar to other parts of the World.


Assuntos
Mercúrio/análise , Rios , Poluentes da Água/análise , Agricultura , Inglaterra , Indústrias , Análise de Regressão
14.
J Environ Monit ; 12(9): 1747-55, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20697627

RESUMO

Precipitation samples have been collected on a monthly basis from a network of 10 sites in Great Britain (GB) in order to estimate background mercury (Hg) deposition in the rural environment. Collection started in February 2005 and results presented here cover the period up to June 2009. The annual volume-weighted mean (AVWM) Hg concentrations range from 1.0 ng L(-1) at Cockley Beck in the Lake District in 2006 to 8.8 ng L(-1) at Heigham Holmes on the Norfolk Coast England in 2008. The largest validated solution concentrations were 33.7 ng L(-1) Hg measured at Cockley Beck in May 2008. The large difference in rainfall amount between sites means that the remote site at Cockley Beck has both the lowest long-term AVWM concentration (1.6 ng L(-1)) and the greatest annual flux is greatest at 43 mg ha(-1) yr(-1). Predicted deposition tends to be much greater in western Britain where the greater rainfall occurs. Because some observations are very close to the analytical detection limit (1.0 ng L(-1)), rigorous cleaning procedures, the use of replicate samplers to monitor contamination, and the inclusion of 'bottle blanks' are required to obtain valid measurements of Hg in the bulk deposition. Deposition in rural sites is equivalent to about 10% of the estimated magnitude of known emissions in GB.


Assuntos
Monitoramento Ambiental , Mercúrio/análise , Chuva/química , Poluentes Químicos da Água/análise , Atmosfera/química , Mercúrio/normas , Reino Unido , Poluentes Químicos da Água/química , Poluição Química da Água/estatística & dados numéricos
15.
Rapid Commun Mass Spectrom ; 24(12): 1805-9, 2010 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-20499326

RESUMO

Studying ecosystem processes in the context of carbon cycling and climate change has never been more important. Stable carbon isotope studies of gas exchange within terrestrial ecosystems are commonly undertaken to determine sources and rates of carbon cycling. To this end, septum-capped vials ('Exetainers') are often used to store samples of CO(2) prior to mass spectrometric analysis. To evaluate the performance of such vials for preserving the isotopic integrity (delta(13)C) and concentration of stored CO(2) we performed a rigorous suite of tests. Septum-capped vials were filled with standard gases of varying CO(2) concentrations (approximately 700 to 4000 ppm), delta(13)C values (approx. -26.5 to +1.8 per thousand(V-PDB)) and pressures (33 and 67% above ambient), and analysed after a storage period of between 7 and 28 days. The vials performed well, with the vast majority of both isotope and CO(2) concentration results falling within the analytical uncertainty of chamber standard gas values. Although the study supports the use of septum-capped vials for storing samples prior to mass spectrometric analysis, it does highlight the need to ensure that sampling chamber construction is robust (air-tight).

16.
Ann Afr Med ; 8(1): 52-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19763008

RESUMO

BACKGROUND: Type 2 diabetes (T2D) is a major cause of chronic kidney disease. Control of hypertension and the use of angiotensin converting enzyme inhibitors (ACEI) and/or angiotensin II receptor blockers especially in those with proteinuria have been shown to protect against chronic kidney disease and delay its progression to kidney failure. METHODS: We reviewed the medical records of 169 patients at 12 months with a view of auditing the screening for chronic kidney disease and the use of renoprotective measures. RESULTS: Urinalysis was done in 49.1% and serum creatinine in 50.3%. No patient had glomerular filtration rate estimated. Seventy nine (67.6%) of the hypertensive patients were on anti-hypertensives. ACEI was used in 49 (45.8%) of these patients BP control was optimal in 29.1%. CONCLUSION: There is poor adherence to guidelines on chronic kidney disease screening and renoprotection in T2D.


Assuntos
Auditoria Clínica/métodos , Diabetes Mellitus Tipo 2/complicações , Falência Renal Crônica/diagnóstico , Adulto , Idoso , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Anti-Hipertensivos/efeitos adversos , Creatinina/sangue , Progressão da Doença , Feminino , Fidelidade a Diretrizes , Hospitais de Ensino , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Falência Renal Crônica/etiologia , Falência Renal Crônica/prevenção & controle , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Proteinúria/fisiopatologia , Urinálise/métodos
17.
Arch Dis Child ; 94(9): 720-3, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19357123

RESUMO

INTRODUCTION: The aim of this prospective audit was to assess the effectiveness and safety of rectal paraldehyde in the management of acute, including prolonged, tonic-clonic convulsions. There are very limited published data on its effectiveness and safety, and previous data have focused on its intramuscular route of administration. METHODS: Four hospitals participated in the study. Information was collected on each dose of paraldehyde used for the treatment of a tonic-clonic convulsion over 1 year. Data were not included on patients treated with rectal paraldehyde for other seizure types or non-convulsive status epilepticus. RESULTS: Data analysis was undertaken regarding 53 episodes in 30 patients. Patient's ages ranged from 5 months to 16 years (mean 6.12 years, median 5.91 years). A pre-existing diagnosis of epilepsy was recorded in 35 episodes (66%). The mean dose of paraldehyde was 0.65 ml/kg (SD 0.22, 95% CI 0.59 to 0.71) and median dose 0.79 ml/kg. Rectal paraldehyde terminated the convulsion in 33 (62.3%) of the 53 episodes. In the 35 episodes where a pre-existing diagnosis of epilepsy was recorded, paraldehyde stopped the convulsion on 26 (74.3%) occasions. There was no difference in the dose of paraldehyde between the episodes where the convulsion was or was not terminated. There was no recorded respiratory depression in any episode. CONCLUSIONS: This study provides unique evidence that rectal paraldehyde is effective and safe in treating acute prolonged tonic-clonic convulsions. This would appear to confirm that paraldehyde should remain a treatment for the management of prolonged tonic-clonic convulsions, including convulsive status epilepticus.


Assuntos
Anticonvulsivantes/administração & dosagem , Epilepsia Tônico-Clônica/tratamento farmacológico , Auditoria Médica/métodos , Paraldeído/administração & dosagem , Doença Aguda , Administração Retal , Adolescente , Anticonvulsivantes/uso terapêutico , Criança , Pré-Escolar , Esquema de Medicação , Humanos , Lactente , Paraldeído/uso terapêutico , Estudos Prospectivos , Segurança , Resultado do Tratamento
18.
Poult Sci ; 85(3): 537-45, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16553286

RESUMO

A technique was developed to record intracranial cerebrospinal fluid pressure (iCSFp) in chicks and mature chickens. Using that procedure, 2 methods were found to effect a significant elevation in intracranial pressure: 1) feeding a purified diet to roosters for 40 d containing 25% of the bird's requirement for vitamin A, and 2) ligating both jugular veins in birds. The purified diet significantly reduced plasma retinol levels from 1.080 to 0.046 microg/mL, and iCSFp was significantly elevated from 63.0 to 106.0 mmH2O (P < or = 0.05). Two limitations for using hypovitaminosis A diets were capillary fragility and a cisterna magna that did not develop to the size of that structure in birds of the same age fed control diets with adequate vitamin A content. The second procedure, a reversible surgical technique, showed that within 2.5 h from jugular vein ligation, intracranial pressure rose to 109.7 mmH2O, comparable with levels attained following feeding a vitamin A deficient diet to roosters. Bilateral clamping of the jugular veins overnight resulted in an elevation of iCSFp to 127 +/- 8.86 mmH2O. Results suggest that the chicken may be a useful animal model to investigate intracranial hypertension and its accompanying headaches known to occur in humans.


Assuntos
Galinhas/fisiologia , Dieta/veterinária , Pressão Intracraniana , Veias Jugulares/cirurgia , Ligadura/veterinária , Deficiência de Vitamina A , Envelhecimento , Ração Animal , Animais , Peso Corporal , Ligadura/métodos , Masculino
19.
Dig Liver Dis ; 37(1): 10-22, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15702854

RESUMO

OBJECTIVE: This is our final report on the clinical effectiveness and safety of long-term pantoprazole in patients with severe peptic ulcer or reflux disease during continuous treatment for up to 5 years. METHODS: Patients (n= 150) with peptic ulcer or reflux erosive oesophagitis running an aggressive course or with complications, and refractory to H2-receptor antagonists, were entered into this 5-year programme. Assessment was by serial endoscopy, clinical examination, serum gastrin estimation, gastric mucosal histology and mucosal endocrine cell quantification. RESULTS: Healing results were presented earlier. The estimated rates of remission on maintenance treatment with pantoprazole (n = 115) were 82% at 1 year, 75% at 2 years, 72% at 3 years, 70% at 4 years and 68% at 5 years. Helicobacter pylori infection appeared not to influence the outcome in reflux patients, with roughly two-thirds continuing in remission irrespective of infection. Only four patients had adverse events considered to be definitely related to pantoprazole. Median gastrin levels rose by 1.5-2-fold and were higher in those with H. pylori infection; 13 patients had levels >500 ng/L on at least one occasion, but these high levels were not sustained. Histological changes were more marked in patients infected with H. pylori: chronic gastritis decreased in the antrum and increased in the corpus, which also showed atrophic changes. The total number of endocrine cells in the antrum showed little variation over 60 months but fell by around one-third in the corpus. CONCLUSION: Long-term treatment with pantoprazole is effective and safe.


Assuntos
Antiulcerosos/uso terapêutico , Benzimidazóis/uso terapêutico , Omeprazol/análogos & derivados , Omeprazol/uso terapêutico , Úlcera Péptica/tratamento farmacológico , Sulfóxidos/uso terapêutico , 2-Piridinilmetilsulfinilbenzimidazóis , Adulto , Idoso , Contagem de Células , Células Enteroendócrinas , Feminino , Mucosa Gástrica/citologia , Células Secretoras de Gastrina , Gastrinas/sangue , Gastrite/tratamento farmacológico , Infecções por Helicobacter/sangue , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Humanos , Masculino , Pessoa de Meia-Idade , Pantoprazol , Úlcera Péptica/sangue , Úlcera Péptica/microbiologia
20.
Radiat Meas ; 37(4-5): 527-34, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12856693

RESUMO

In this paper we present the concept of a robotic instrument for in situ luminescence dating of near-surface sediments on Mars. The scientific objectives and advantages to be gained from the development of such an instrument are described, and the challenges presented by the Mars surface environment to the design and operation of the instrument are outlined.


Assuntos
Sedimentos Geológicos/análise , Luminescência , Marte , Robótica , Voo Espacial/instrumentação , Radiação Cósmica , Desenho de Equipamento , Evolução Planetária , Meio Ambiente Extraterreno , Prótons , Atividade Solar , Astronave/instrumentação , Manejo de Espécimes
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