RESUMEN
The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development1. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure2. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in MC3R, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking Mc3r had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of Mc3r is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.
Asunto(s)
Desarrollo Infantil/fisiología , Estado Nutricional/fisiología , Pubertad/fisiología , Receptor de Melanocortina Tipo 3/metabolismo , Maduración Sexual/fisiología , Adolescente , Anciano de 80 o más Años , Animales , Niño , Ciclo Estral/genética , Ciclo Estral/fisiología , Femenino , Homocigoto , Humanos , Hipotálamo/citología , Hipotálamo/fisiología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Melanocortinas/metabolismo , Menarquia/genética , Menarquia/fisiología , Ratones , Fenotipo , Pubertad/genética , Receptor de Melanocortina Tipo 3/deficiencia , Receptor de Melanocortina Tipo 3/genética , Maduración Sexual/genética , Factores de Tiempo , Aumento de PesoRESUMEN
Medical therapy has become first line treatment for Benign Prostatic Hypertrophy (BPH) and in many cases TURP may no longer be required. Proof and quantification of this evolution in practice has been somewhat elusive and provided the principle impetus for this study. This is a retrospective study of BPH management in Republic of Ireland from 1995 to 2008. National treatment databases were sourced for numbers undergoing TURP and pharmacotherapy prescribing data was obtained from individual pharmaceutical companies. A total of 28,240 TURP's were performed nationally between 1995 and 2008. TURP's performed annually, decreased by 1,494 (51%), alpha-blocker prescriptions increased from 8,710 to 302,159 units and the number of urology trainees increased by 10 (60%). Clear association between decreases in TURP's and increases in pharmacotherapy for BPH is demonstrated. Implications on training likely exist and will require proper evaluation in order to maintain future standards in this surgical practice.
Asunto(s)
Hiperplasia Prostática/tratamiento farmacológico , Resección Transuretral de la Próstata/tendencias , Inhibidores de 5-alfa-Reductasa/uso terapéutico , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapéutico , Utilización de Medicamentos/tendencias , Humanos , Irlanda , Masculino , Hiperplasia Prostática/cirugía , Estudios Retrospectivos , Resección Transuretral de la Próstata/estadística & datos numéricosRESUMEN
*Hybridization allows transgenes and other crop alleles to spread to wild/weedy populations of related taxa. Researchers have debated whether such alleles will persist because low hybrid fitness and linkage to domestication traits could severely impede introgression. *To examine variation in the fates of three unlinked crop alleles, we monitored four experimental, self-seeding, hybrid populations of Raphanus raphanistrum x Raphanus sativus (radish) in Michigan, USA, over a decade. We also compared the fecundity of advanced-generation hybrid plants with wild plants in a common garden experiment. *Initially, F(1) hybrids had reduced fitness, but the populations quickly evolved wild-type pollen fertility. In Year 10, the fecundity of plants from the experimental populations was similar to that of wild genotypes. Crop-specific alleles at the three loci persisted for 10 yr in all populations, and their frequencies varied among loci, populations and years. *This research provides a unique case study of substantial variation in the rates and patterns of crop allele introgression after a single hybridization event. Our findings demonstrate that certain crop alleles can introgress easily while others remain rare, supporting the assumption that neutral or beneficial transgenes that are not linked to maladaptive traits can persist in the wild.
Asunto(s)
Alelos , Productos Agrícolas/genética , Genética de Población , Raphanus/genética , Simulación por Computador , Cruzamientos Genéticos , Fertilidad/genética , Flujo Genético , Aptitud Genética , Marcadores Genéticos , Hibridación Genética , Polen/genética , Dinámica Poblacional , Tamaño de la Muestra , Semillas/genética , Especificidad de la Especie , Factores de TiempoRESUMEN
PURPOSE: We conducted a phase III trial to investigate the timing of chemotherapy with respect to surgery for patients with resectable but high-risk urothelial cancer. The trial was also designed to evaluate the accuracy of clinical staging in patients with locally advanced cancer and the prognostic significance of chemotherapy-induced downstaging. PATIENTS AND METHODS: A total of 140 uniformly evaluated patients with locally advanced urothelial cancer were studied. Planned treatment was five cycles of chemotherapy (M-VAC: methotrexate, vinblastine, doxorubicin, and cisplatin) plus radical cystectomy and pelvic lymph node dissection. Patients were randomly assigned to receive either two courses of neoadjuvant M-VAC followed by surgery plus three additional cycles of chemotherapy, or, alternatively, to have initial cystectomy followed by five cycles of adjuvant chemotherapy. RESULTS: There were no significant differences in outcome between the two groups. By intent-to-treat, 81 patients (58%) remain disease-free, with median follow-up of 6.8 years. We confirmed a high rate of clinical understaging in this cohort, especially among patients showing lymphovascular invasion on biopsy. Patients with no residual muscle-invasive disease at cystectomy after neoadjuvant chemotherapy were likely to be cured. CONCLUSION: These results lend further support to the impression from small randomized trials that, in a high-risk cohort, there is an improved cure fraction by the combination of multiagent chemotherapy and surgery, although we found no preferred sequence. Importantly, it is possible to select appropriate patients for such therapy on the basis of clinical staging information. These results establish a benchmark of outcome for this cohort.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Vejiga Urinaria/cirugía , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioterapia Adyuvante , Cisplatino/administración & dosificación , Terapia Combinada , Cistectomía , Doxorrubicina/administración & dosificación , Femenino , Humanos , Masculino , Metotrexato/administración & dosificación , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Primarias Secundarias/patología , Cuidados Posoperatorios , Complicaciones Posoperatorias , Cuidados Preoperatorios , Análisis de Supervivencia , Factores de Tiempo , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Vinblastina/administración & dosificaciónRESUMEN
BACKGROUND: Ureteral obstruction (UO) is characterized by reduced blood flow and loss of tissue mass in the involved kidney(s). Vasoactive mediators interact to produce an initial hyperemia, followed by a sustained decrease in renal blood flow in the obstructed kidney. Nitric oxide (NO) has been shown to play a central role in the acute hyperemic response to UO. Its role in the reduced perfusion of prolonged UO is less studied. METHODS: Ureteral obstruction was achieved by ligation of the distal left ureter and maintained for 24 hours. Blood flow was studied in untreated animals and after the administration of the NO synthase (NOS) inhibitor N-mono-methyl L-arginine and the NO donor sodium nitroprusside. Tissue was collected for localization and quantitation of NOS. Serum and renal tissue L-arginine levels were measured in control and UO settings. RESULTS: Blood flow in the obstructed kidney diminished to approximately 50% of control values after 24 hours of UO. NOS blockade led to a further decrease in blood flow. Supplementation with exogenous nitrates restored renal blood flow to levels approaching control values. Serum and tissue L-arginine levels did not change with UO. NOS expression was seen to increase with increasing duration of obstruction, with staining most pronounced in the renal tubules. CONCLUSIONS: NO plays a vasodilatory role even in the hypoperfusion of prolonged UO. The administration of exogenous nitrates has a restorative effect on blood flow, suggesting therapeutic potential in UO.
Asunto(s)
Óxido Nítrico/fisiología , Circulación Renal/fisiología , Obstrucción Ureteral/fisiopatología , Animales , Arginina/sangre , Arginina/metabolismo , Inhibidores Enzimáticos/farmacología , Túbulos Renales/enzimología , Masculino , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , Nitroprusiato/farmacología , Ratas , Ratas Sprague-Dawley , Circulación Renal/efectos de los fármacos , omega-N-Metilarginina/farmacologíaRESUMEN
Finite state control is an established technique for the implementation of intention detection and activity co-ordination levels of hierarchical control in neural prostheses, and has been used for these purposes over the last thirty years. The first finite state controllers (FSC) in the functional electrical stimulation of gait were manually crafted systems, based on observations of the events occurring during the gait cycle. Subsequent systems used machine learning to automatically learn finite state control behaviour directly from human experts. Recently, fuzzy control has been utilised as an extension of finite state control, resulting in improved state detection over standard finite state control systems in some instances. Clinical experience over the last thirty years has been positive, and has shown finite state control to be an effective and intuitive method for the control of functional electrical stimulation (FES) in neural prostheses. However, while finite state controlled neural prostheses are of interest in the research community, they are not widely used outside of this setting. This is largely due to the cumbersome nature of many neural prostheses which utilise externally mounted gait sensors and FES electrodes. FES-based control of movement has been subject to the constraints of artificial sensor and FES actuator technologies. However, continued advances in natural sensors and implanted multi-channel stimulators are broadening the boundaries of artificial control of movement, driving an evolutionary process towards increasingly human-like control of FES-based gait rehabilitation systems.
Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Marcha , Prótesis e Implantes , Diseño de PrótesisRESUMEN
The purpose of this study was to determine the safety, efficacy and impact on quality of life of recombinant human erythropoietin (r-HuEPO) for cancer patients undergoing radiotherapy (RT). An open-labelled randomized design was used, with patients randomized to either treatment or control arms. Patients in the treatment arm received r-HuEPO given by subcutaneous injection at a dose of 200 units kg(-1) day(-1) plus oral iron supplements (ferrous sulphate 325 mg p.o. t.i.d.). Entry was restricted to patients with carcinoma of the lung, uterine cervix, prostate or breast who presented for RT with anaemia parameters reflective of 'the anaemia of chronic disease'. Radiotherapy policies (portals, doses, fraction size, etc.) were determined by the site and stage of disease. Complete blood counts (CBCs) were obtained weekly. The target level of haemoglobin was 15 g dl(-1) for men and 14 g dl(-1) for women. Quality of life (QOL) was assessed weekly by using an analogue scale to judge energy, activities of daily living and overall quality of life. Forty-eight patients were entered in the study, 24 in the treatment arm and 24 in the control arm. The prerandomization demographic characteristics and mean laboratory values were comparable in both arms. The mean haemoglobin at completion was 13.6 g dl(-1) for r-HuEPO-treated patients compared with 11.0 g dl(-1) for control subjects (P = 0.0012). Patients who received r-HuEPO demonstrated a mean weekly haemoglobin increase of 0.41 g dl(-1) compared with a decrease in mean haemoglobin level in controls for 6 of the 7 weeks of the study (mean weekly decrease of 0.073 g dl(-1)). Target levels of haemoglobin were achieved by 41.6% of r-HuEPO-treated patients compared with none of the control subjects. The mean platelet count declined in both arms of the study with RT but the decline from pretreatment was less rapid in r-HuEPO-treated patients (11.2% decrease) compared with controls (26.3% decrease) and was statistically significant during weeks 4-6. Toxicity was minor with only mild irritation at the injection site. Mean quality of life end points were superior in the treatment arm but not statistically significant. r-HuEPO had a beneficial effect on weekly haemoglobin levels in patients undergoing RT with response rates similar to other studies. There was also a less rapid decline in weekly platelet counts in r-HuEPO-treated patients compared with control subjects. Further studies are needed to address the optimum dose and scheduling as well as the impact of r-HuEPO on clinical outcomes.
Asunto(s)
Anemia/terapia , Eritropoyetina/uso terapéutico , Neoplasias/radioterapia , Eritropoyetina/administración & dosificación , Eritropoyetina/efectos adversos , Femenino , Hemoglobinas/análisis , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Calidad de Vida , Proteínas RecombinantesRESUMEN
The aim of the study was to assess the analgesic effect of tramadol in the relief of pain after dentoalveolar operations that involve the removal of bone and suturing. Four-hundred and fifty-two patients over the age of 18 years who were to undergo removal of impacted teeth (n = 362), removal of root (n = 79), or alveolectomy, enucleation of cysts, or removal of soft tissue (n = 11) under local anesthesia were studied. Patients were randomly allocated to receive tramadol 100 mg or 50 mg four times daily, or 50 mg twice daily, or placebo. Median pain scores on the day of operation in the three tramadol groups were similar (2 in each group, ranges 1-5, 1-4.8, and 1-5 respectively) and were all significantly lower than that in the placebo group (2.3 range 1-4.2). The median number of Paracetamol tablets taken by patients in the three tramadol groups was 2 (ranges 0-8, 0-12 and 0-8 respectively), and were all significantly less than in the placebo group (4, range 0-12). More patients given tramadol reported complete pain relief than the placebo group. The advantages of tramadol continued over the next 2 days. There were no serious or unexpected adverse effects. It is concluded that tramadol is an effective analgesic after dentoalveolar operations.
Asunto(s)
Alveolectomía , Analgésicos Opioides/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Enfermedades Dentales/cirugía , Tramadol/uso terapéutico , Acetaminofén/administración & dosificación , Acetaminofén/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alveolectomía/efectos adversos , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/efectos adversos , Anestesia Dental , Anestesia Local , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal/cirugía , Quistes Odontogénicos/cirugía , Dimensión del Dolor , Placebos , Técnicas de Sutura/efectos adversos , Comprimidos , Raíz del Diente/cirugía , Diente Impactado/cirugía , Tramadol/administración & dosificación , Tramadol/efectos adversosRESUMEN
Calmidazolium [R24571, 1-[bis(4-chlorophenyl)methyl]-3-[2-(2,4-dichlorophenyl)-2-[(2,4- dichlorophenyl)methoxy]ethyl]-1H-imidazolium chloride] is a potent calmodulin inhibitor. This paper describes the synthesis and properties of the enantiomers of calmidazolium from the enantiomers of miconazole [1(N)-(2-(2,4-dichlorobenzyloxy)-2-(2,4 dichlorophenyl))-ethyl imidazole], prepared from the racemate by chiral preparative scale high performance liquid chromatography. Overlap between ligand and protein resonances in the aromatic region of the 1H NMR spectrum of the calmidazolium-calmodulin complexes has been obviated by preparation of the protein with all of its nine phenylalanine rings deuterated (Phe-d5 calmodulin). This has been accomplished by the overexpression of calmodulin derived from Trypanosoma brucei rhodiesiense in E. coli in a medium supplemented with ring-deuterated phenylalanine. The kinetics of binding of each enantiomer are slow on the 1H NMR time scale as judged by the behaviour of the H2 resonance of Histidine-107, which is clearly visible under the sample conditions used. The aromatic spectral regions of the protein-bound (+) and (-) enantiomers contrast strikingly, reflecting differences in bound environment and/or conformation.