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1.
Phys Chem Chem Phys ; 26(17): 13279-13286, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639080

RESUMO

A combined solvent system composed of an acidic and a neutral extractant is demonstrated as an effective system for the mutual separation of lanthanides and actinides from nitric acid solutions. The geometry and stability of various possible complexes formed under extraction and stripping conditions in a combined solvent system composed of N,N-dioctyl hydroxyacetamide (DOHyA) and bis(2-ethylhexyl)phosphoric acid (HDEHP) in the n-dodecane medium were studied both experimentally and theoretically. Experimental observations of the distribution ratios of Am(III) and Eu(III) in the combined solvent system revealed synergistic extraction of trivalent metal ions at all nitric acid concentrations. Density functional theory (DFT) calculations were employed to understand the geometric and electronic properties of the ligands and their corresponding complexes with Am(III) and Eu(III). The calculated results indicate that the feasibility and behaviour of complex formation in the combined solvent system using different methods are based on the energetic aspects of the formation reactions. The study also reveals the participation of the neutral and acid extractants in the combined solvent system facilitating the separation of Eu(III) and Am(III) from high-level liquid waste.

2.
Lancet ; 396(10243): 50-61, 2020 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-32622397

RESUMO

BACKGROUND: Transurethral resection of the prostate (TURP) is the standard operation for benign prostatic obstruction. Thulium laser transurethral vaporesection of the prostate (ThuVARP) is a technique with suggested advantages over TURP, including reduced complications and hospital stay. We aimed to investigate TURP versus ThuVARP in men with lower urinary tract symptoms or urinary retention secondary to benign prostatic obstruction. METHODS: In this randomised, blinded, parallel-group, pragmatic equivalence trial, men in seven UK hospitals with bothersome lower urinary tract symptoms or urinary retention secondary to benign prostatic obstruction were randomly assigned (1:1) at the point of surgery to receive ThuVARP or TURP. Patients were masked until follow-up completion. Centres used their usual TURP procedure (monopolar or bipolar). All trial surgeons underwent training on the ThuVARP technique. Co-primary outcomes were maximum urinary flow rate (Qmax) and International Prostate Symptom Score (IPSS) at 12-months post-surgery. Equivalence was defined as a difference of 2·5 points or less for IPSS and 4 mL per s or less for Qmax. Analysis was done according to the intention-to-treat principle. The trial is registered with the ISRCTN Registry, ISRCTN00788389. FINDINGS: Between July 23, 2014, and Dec 30, 2016, 410 men were randomly assigned to ThuVARP or TURP, 205 per study group. TURP was superior for Qmax (mean 23·2 mL per s for TURP and 20·2 mL per s for ThuVARP; adjusted difference in means -3·12, 95% CI -5·79 to -0·45). Equivalence was shown for IPSS (mean 6·3 for TURP and 6·4 for ThuVARP; adjusted difference in means 0·28, -0·92 to 1·49). Mean hospital stay was 48 h in both study groups. 91 (45%) of 204 patients in the TURP group and 96 (47%) of 203 patients in the ThuVARP group had at least one complication. INTERPRETATION: TURP and ThuVARP were equivalent for urinary symptom improvement (IPSS) 12-months post-surgery, and TURP was superior for Qmax. Anticipated laser benefits for ThuVARP of reduced hospital stay and complications were not observed. FUNDING: UK National Institute for Health Research Health Technology Assessment Programme.


Assuntos
Lasers de Estado Sólido/uso terapêutico , Sintomas do Trato Urinário Inferior/cirurgia , Túlio , Ressecção Transuretral da Próstata , Retenção Urinária/cirurgia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Reino Unido
3.
Trials ; 18(1): 179, 2017 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-28412960

RESUMO

BACKGROUND: Transurethral resection of the prostate (TURP) has been the standard operation for benign prostatic obstruction (BPO) for 40 years, with approximately 25,000 procedures performed annually, and has remained largely unchanged. It is generally a successful operation, but has well-documented risks for the patient. Thulium laser transurethral vaporesection of the prostate (ThuVARP) vaporises and resects the prostate using a surgical technique similar to TURP. The small amount of study data currently available suggests that ThuVARP may have certain advantages over TURP, including reduced blood loss and shorter hospital stay, earlier return to normal activities, and shorter duration of catheterisation. DESIGN: A multicentre, pragmatic, randomised, controlled, parallel-group trial of ThuVARP versus standard TURP in men with BPO. Four hundred and ten men suitable for prostate surgery were randomised to receive either ThuVARP or TURP at four university teaching hospitals, and three district general hospitals. The key aim of the trial is to determine whether ThuVARP is equivalent to TURP judged on both the patient-reported International Prostate Symptom Score (IPSS) and the maximum urine flow rate (Qmax) at 12 months post-surgery. DISCUSSION: The general population has an increased life expectancy. As men get older their prostates enlarge, potentially causing BPO, which often requires surgery. Therefore, as the population ages, more prostate operations are needed to relieve obstruction. There is hence sustained interest in the condition and increasing need to find safer techniques than TURP. Various laser techniques have become available but none are widely used in the NHS because of lengthy training required for surgeons or inferior performance on clinical outcomes. Promising initial evidence from one RCT shows that ThuVARP has equivalent clinical effectiveness when compared to TURP, as well as other potential advantages. As ThuVARP uses a technique similar to that used in TURP, the learning curve is short, potentially making it also very quickly generalisable. This randomised study is designed to provide the high-quality evidence, in an NHS setting, with a range of patient-reported, clinical and cost-effectiveness outcomes, which will underpin and inform future NICE guidance. TRIAL REGISTRATION: ISRCTN registry, ISRCTN00788389 . Registered on 20 September 2013.


Assuntos
Custos Hospitalares , Terapia a Laser/economia , Lasers , Prostatectomia/economia , Hiperplasia Prostática/cirurgia , Medicina Estatal/economia , Túlio/economia , Ressecção Transuretral da Próstata/economia , Protocolos Clínicos , Análise Custo-Benefício , Hospitais de Distrito , Hospitais Gerais , Hospitais de Ensino , Humanos , Terapia a Laser/efeitos adversos , Terapia a Laser/instrumentação , Lasers/efeitos adversos , Masculino , Medidas de Resultados Relatados pelo Paciente , Prostatectomia/efeitos adversos , Prostatectomia/instrumentação , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/fisiopatologia , Recuperação de Função Fisiológica , Projetos de Pesquisa , Túlio/efeitos adversos , Fatores de Tempo , Ressecção Transuretral da Próstata/efeitos adversos , Resultado do Tratamento , Reino Unido , Urodinâmica
5.
Indian J Exp Biol ; 43(8): 671-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16121707

RESUMO

Median third eye was found to develop from transplanted pineal gland of external gill stage tadpoles in the recipient 5 toe stage tadpoles of Bufo melanostictus. Pineal gland along with a bit part of brain tissue of the donor external gill stage tadpole was cut out and transplanted into a pit made between two lateral eyes of 5 toe stage recipient tadpoles. Half of the operated tadpoles were treated with vitamin A (15 IU/ml.) for 15 days. Median "third eye" was found to develop in the both untreated and vitamin A treated tadpoles. However, vitamin A increased the percentage of the development of median eyes. Morphological and histological study revealed that newly transformed median eyes were similar to that of normal functional eyes. A stalk like structure developed which connects the median eye to the brain. The median third eye could not develop when pineal gland of 5 toe stage mature tadpole was transplanted into the tadpole of the same age.


Assuntos
Bufonidae/crescimento & desenvolvimento , Olho , Morfogênese , Glândula Pineal , Animais , Olho/efeitos dos fármacos , Olho/embriologia , Larva/crescimento & desenvolvimento , Morfogênese/efeitos dos fármacos , Glândula Pineal/efeitos dos fármacos , Glândula Pineal/embriologia , Vitamina A/farmacologia
6.
Fresenius J Anal Chem ; 369(1): 63-70, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11210233

RESUMO

A microwave digestion method in a closed vessel was developed for the determination of trace metals in atmospheric aerosols using inductively coupled plasma mass spectrometry (ICP-MS). A recovery study for the elements V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sb, and Pb was conducted using multi-elemental standard solutions, NIST 1633b Trace Elements in Coal Fly Ash, and NIST 1648 Urban Particulate Matter. A simple digestion method using only HNO3/H2O2 gave good recoveries (90%-108%) for all elements except Cr in SRM 1648, but yielded low recoveries for SRM 1633b. A more robust method using HNO3/H2O2/HF/H3BO3 yielded higher recoveries (82%-103%) for the lighter elements (V-Zn) in SRM 1633b, and improved the Cr recovery in SRM 1648, but decreased the Se recovery in both SRMs. A comparative analysis of aerosol samples obtained at a remote mountain location Nathiagali, Pakistan (2.5 km above mean sea level), and Mayville, New York, downwind from the highly industrialized Midwestern United States, was carried out using Instrumental Neutron Activation Analysis (INAA) for the elements Cr, Mn, Fe, Co, Zn, As, Se, and Sb. The simple digestion method yielded excellent agreement for Cr, Fe, Zn, As, Se, and Sb, with slopes of the ICP-MS vs. INAA regressions of 0.90-1.00 and R2 values of 0.96-1.00. The regressions for Mn and Co had slopes of 0.82 and 0.84 with R2 values of 0.83 and 0.82, respectively. Addition of HF/H3BO3 did not improve the correlation for any of the elements and degraded the precision somewhat. The technique provides sensitivity and accuracy for trace elements in relatively small aerosol samples used in atmospheric chemistry studies related to SO2 oxidation in cloud droplets. The ability to determine concentrations of a very large number of elements from a single analysis will permit source apportionment of various trace pollutants and hence strategies to control the sources of air pollution. This is particularly important as the health effects of particulate matter are increasingly recognized.


Assuntos
Poluentes Atmosféricos/análise , Metais/análise , Micro-Ondas , Aerossóis , Atmosfera , Espectrometria de Massas , New York , Paquistão
7.
J Biosci ; 26(5): 577-81, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11807288

RESUMO

After removal of both the lateral eyes of external gill stage tadpoles of the toad Bufo melanostictus, the pineal organ gets transformed into a median eye. This type of transformation occurs in tadpoles of both control and vitamin A treated groups. However, vitamin A increases the likelihood of homeotic regeneration (57% in the control group and 71% in the vitamin A treated group). Histological studies showed that the newly transformed median eye developed from the pineal organ. The pineal eye so developed possessed all components of a normal eye such as a retina, sensory cells and lens.


Assuntos
Bufonidae/crescimento & desenvolvimento , Genes Homeobox , Larva/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Vitamina A/farmacologia , Animais , Larva/fisiologia , Regeneração/genética
8.
Br J Urol ; 81(1): 68-72, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9467479

RESUMO

OBJECTIVE: To evaluate the clinical and urodynamic outcome of partial detrusor myectomy in patients with idiopathic detrusor instability and neuropathic hyper-reflexia. PATIENTS AND METHODS: Seventeen patients with idiopathic detrusor instability and 10 with hyper-reflexia and symptoms not responding to non-surgical treatment underwent partial detrusor myectomy. The clinical and urodynamic results before and after myectomy were compared and the patient's subjective assessment of the outcome documented. RESULTS: There was an overall improvement in 17 of 27 patients (63%) but the success rate was higher in those with idiopathic instability (12 of 17) than in those with neuropathy (five of 10). There was urodynamic evidence of reduced bladder contractility and an improvement in the storage characteristics of the bladder in most of the patients treated. CONCLUSIONS: Partial detrusor myectomy is relatively simple and is associated with minimum morbidity and an acceptable success rate. The procedure alters the urodynamic behaviour of the bladder and leads to symptomatic and objective improvement, giving better results with idiopathic than with neuropathic detrusor overactivity. Detrusor myectomy may be offered to patients with detrusor overactivity unresponsive to conventional management. The option of enterocystoplasty is still open to patients with an unsuccessful outcome. However, the long-term results and surgical variations of the technique should be evaluated further.


Assuntos
Músculo Liso/cirurgia , Reflexo Anormal , Doenças da Bexiga Urinária/cirurgia , Bexiga Urinária/cirurgia , Transtornos Urinários/cirurgia , Seguimentos , Humanos , Resultado do Tratamento , Urodinâmica
9.
Acta Oncol ; 36(2): 165-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9140433

RESUMO

A detailed analysis of host-tumor factors and interstitial physical factors influencing the disease-free control in carcinoma of the tongue was carried out. Twenty-eight cases of carcinoma of the tongue T1-3, NO-1, MO were treated radically with combined external irradiation and 192Iridium interstitial brachytherapy (one patient received brachytherapy only). The teletherapy dose ranged from 44 Gy to 56 Gy (average 48 Gy), the brachytherapy dose ranged from 16 Gy to 55 Gy (average 22 Gy). The interstitial practice involved loop technique in all the cases. Dose distribution analysis to assess factors influencing local control included indices of dose rate, source activity, inter-planar distance, and discontinuity in the prescribed isodose in other planes when compared to mid-plane. Two-year actuarial disease-free survival (DFS) was 46% with primary treatment and 63% when salvage treatment was also included. DFS was significantly poorer when the interplanar distance at mid-plane exceeded 10 mm (p < 0.05). Similarly, tumor control was poorer (p < 0.008) when there was discontinuity in the prescribed isodose in 1 or 2 planes (1 cm superior and inferior to mid-plane). Interplanar distance of around 10 mm, prescribed isodose continuity in all three planes and limiting the dose maximum within a factor of 2 will optimize the results of interstitial implants.


Assuntos
Braquiterapia/métodos , Radioisótopos de Irídio/uso terapêutico , Neoplasias da Língua/radioterapia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade
11.
J AOAC Int ; 79(1): 170-4, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8620106

RESUMO

An analytical method for determining butyltin chlorides in air at low nanogram-per-cubic-meter levels was developed. Butyltin chlorides investigated were mono-n-butyltin trichloride (MBTC), di-n-butyltin dichloride (DBTC), and tri-n-butyltin chloride (TBTC). These tin chlorides were trapped on cartridges packed with Porapak-N, eluted with methylene chloride containing 0.3% HCl, hydridized with sodium borohydride, and analyzed by capillary gas chromatography with flame photometric detection. On the basis of a 20 m3 sample, a detection limit of 0.05 ng/m3 can be achieved.


Assuntos
Poluentes Atmosféricos/análise , Cromatografia Gasosa/métodos , Compostos Orgânicos de Estanho/análise , Boroidretos , Cromatografia Gasosa/estatística & dados numéricos , Cloreto de Metileno , Microquímica , Compostos de Trialquitina/análise
13.
Br J Urol ; 74(6): 733-5, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7827843

RESUMO

OBJECTIVES: To assess whether the synthetic vasopressin analogue desmopressin [1-desamino 8-D-arginine vasopressin] is efficacious and safe in the management of nocturia +/- enuresis in patients with multiple sclerosis. PATIENTS AND METHODS: Twenty-two women and 11 men, under 65 years of age, with clinically definite multiple sclerosis and nocturnal frequency +/- enuresis were entered into the study. A two week placebo run-in, to establish normal voiding patterns, followed by a double-blind, placebo-controlled, cross-over study of 20 micrograms intranasal desmopressin at night-time was carried out. RESULTS: Desmopressin caused a significant decrease in nocturnal urinary frequency, nocturnal urinary volume and the percentage of total daily urine passed at night. There was no significant fall in plasma sodium with desmopressin although there were two cases of asymptomatic hyponatraemia. CONCLUSION: Desmopressin is an efficacious and safe treatment for nocturia +/- enuresis in patients with multiple sclerosis.


Assuntos
Desamino Arginina Vasopressina/uso terapêutico , Esclerose Múltipla/complicações , Transtornos Urinários/tratamento farmacológico , Adulto , Estudos Cross-Over , Método Duplo-Cego , Enurese/tratamento farmacológico , Enurese/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Urinários/etiologia
14.
Br J Urol ; 70(4): 417-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1450852

RESUMO

Chronic testicular pain has many different aetiologies. Identification and treatment of an underlying problem resolve the issue in most cases. However, a proportion of patients with chronic testicular pain have no demonstrable aetiological factor and pose a difficult treatment problem. All of these patients are initially treated by non-surgical measures. Various operations advocated in the literature for non-responders include epididymectomy, scrotal orchiectomy and inguinal orchiectomy, all of which have a significant failure rate. We describe a hitherto unreported operative procedure in a series of 4 patients, with immediate and lasting relief of their pain.


Assuntos
Denervação/métodos , Dor Intratável/cirurgia , Doenças Testiculares/cirurgia , Testículo/inervação , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia , Escroto/inervação , Escroto/cirurgia
15.
Br J Hosp Med ; 47(8): 591-6, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1591560

RESUMO

The use of artificial sphincters for the treatment of urinary incontinence has evolved steadily over the last few decades. Currently available designs are suitable for implantation in male and female patients of all age-groups. This article describes the clinical implications of artificial urinary sphincters in the treatment of incontinent patients.


Assuntos
Incontinência Urinária/cirurgia , Esfíncter Urinário Artificial , Feminino , Humanos , Masculino , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , Prognóstico , Procedimentos Cirúrgicos Operatórios/métodos
16.
Environ Health Perspect ; 79: 273-82, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2495933

RESUMO

Numerous laboratory simulations and real-world events have demonstrated the thermal conversion of neat or high concentration of PCBs into the much more toxic PCDFs. Since millions of mineral oil transformers currently in service contain PCB concentrations in the 50 to 5000 ppm range, the thermal behavior of dilute PCB solutions is of practical and regulatory significance. In this work, neat Aroclor 1254 and 5000 ppm Aroclor 1254 in mineral oil were subjected to pyrolysis and combustion under a range of experimental conditions to define parameters resulting in maximal PCDF yields. The dependence of PCDF yield on Aroclor 1254 concentrations was then investigated in the 5000 to 50 ppm range. Combustion experiments demonstrated that PCDF yields expressed as micrograms PCDF/gram PCB were independent of concentration range, confirming that the process is kinetically first order in PCB. Much lower yields of PCDF were observed in the open tube pyrolysis experiments, as compared to combustion experiments and to earlier and concurrent sealed tube experiments. Slightly improved yields were observed in the pyrolysis experiments at lower concentrations, suggesting the existence of a PCB or PCDF destruction process of higher than first order kinetics. In all cases, yields expressed as micrograms PCDF/gram mixture were sharply and monotonically lower as concentrations decreased between neat or 5000 ppm Aroclor 1254 and 50 ppm Aroclor 1254.


Assuntos
Arocloros , Benzofuranos , Óleo Mineral , Bifenilos Policlorados , Fenômenos Químicos , Química , Temperatura Alta
17.
Indian J Exp Biol ; 27(1): 80-2, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2606527

RESUMO

Electropolarity treatment (0.8V/DC/Cm) was given to the gastrocnemius muscle of B. melanostictus every day for 5 min for 5 days. The glycogen content and aldolase activity levels increased and phosphorylase 'a' activity levels decreased on cathode treatment in muscle, liver and brain while an opposed trend was observed on anode treatment. The heart showed contrasting pattern under both cathode and anode electropolarity treatments.


Assuntos
Glicogênio/metabolismo , Animais , Encéfalo/metabolismo , Bufonidae , Estimulação Elétrica , Fígado/metabolismo , Músculos/metabolismo , Miocárdio/metabolismo
19.
Arch Int Physiol Biochim ; 96(2): 75-9, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2460060

RESUMO

Male albino rats were treated with insulin for one week (acute) and four weeks (chronic). The lactate dehydrogenase (LDH) activity, lactate and pyruvate levels were estimated in the tissues of experimental and control animals. LDH activity decreased in all the tissues of acute- and chronic treated animals whereas the lactate content is elevated. Pyruvate content also showed increment except in heart and pancreas with reference to acute treatment where it is decreased. The hyperinsulinaemia effect in relation to lacticacidaemia and its influence on energy demand and ammonia secretion is discussed.


Assuntos
Insulina/farmacologia , L-Lactato Desidrogenase/metabolismo , Animais , Hiperinsulinismo/metabolismo , Insulina/sangue , Lactatos/metabolismo , Ácido Láctico , Masculino , Piruvatos/metabolismo , Ácido Pirúvico , Ratos , Ratos Endogâmicos , Distribuição Tecidual
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