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1.
Community Ment Health J ; 58(4): 720-728, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34302562

RESUMEN

This study evaluates the implementation of a national advocacy programme for mental health care users, conducted by the South African National Department of Health and the South African Federation for Mental Health. Semi-structured interviews were conducted with care users (n = 18), service providers (n = 9), support persons (n = 6), NGO directors (n = 4), and programme managers in the DoH (n = 4). Although informational benefits were highlighted from programme empowerment sessions, very few advocacy groups were subsequently established. Barriers to establishing and conducting advocacy groups included a lack of follow-up support, pervasive stigma from communities and health care workers, low self-confidence, and a lack of financial resources. Facilitators for establishment of groups included conducting empowerment sessions and identifying 'mental health champions' at clinics, improving mental health training for health workers, dispensing psychiatric medication to patients on the same day, providing funding for non-governmental organisations, conducting national awareness campaigns, and establishing holistic rehabilitation centres for care users.


Asunto(s)
Servicios de Salud Mental , Salud Mental , Personal de Salud , Humanos , Estigma Social , Sudáfrica
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6627-6630, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34892627

RESUMEN

This study investigated the possibility of using functional near infrared spectroscopy (fNIRS) during right- and left-hand motor imagery tasks to select an optimum set of electroencephalography (EEG) electrodes for a brain computer interface. fNIRS has better spatial resolution allowing areas of brain activity to more readily be identified. The ReliefF algorithm was used to identify the most reliable fNIRS channels. Then, EEG electrodes adjacent to those channels were selected for classification. This study used three different classifiers of linear and quadratic discriminant analyses, and support vector machine to examine the proposed method.Clinical Relevance- Reducing the number of sensors in a BCI makes the system more usable for patients with severe disabilities.


Asunto(s)
Interfaces Cerebro-Computador , Electrodos , Electroencefalografía , Humanos , Imágenes en Psicoterapia , Espectroscopía Infrarroja Corta
3.
Sci Rep ; 11(1): 5, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33408364

RESUMEN

This 9-month randomised, parallel, double-blind, single-centre, placebo-controlled study (PROBE, ISRCTN18030882) assessed the impact of probiotic supplementation on bodyweight. Seventy overweight Bulgarian participants aged 45-65 years with BMI 25-29.9 kg/m2 received a daily dose of the Lab4P probiotic comprising lactobacilli and bifidobacteria (50 billion cfu/day). Participants maintained their normal diet and lifestyle over the duration of the study. The primary outcome was change from baseline in body weight and secondary outcomes included changes in waist circumference, hip circumference and blood pressure. A significant between group decrease in body weight (3.16 kg, 95% CI 3.94, 2.38, p < 0.0001) was detected favouring the probiotic group. Supplementation also resulted in significant between group decreases in waist circumference (2.58 cm, 95% CI 3.23, 1.94, p < 0.0001) and hip circumference (2.66 cm, 95% CI 3.28, 2.05, p < 0.0001) but no changes in blood pressure were observed. These findings support the outcomes of a previous shorter-term Lab4P intervention study in overweight and obese participants (PROMAGEN, ISRCTN12562026). We conclude that Lab4P has consistent weight modulation capability in free-living overweight adults.


Asunto(s)
Suplementos Dietéticos , Sobrepeso/dietoterapia , Probióticos/uso terapéutico , Pérdida de Peso/efectos de los fármacos , Bifidobacterium , Presión Sanguínea/efectos de los fármacos , Tamaño Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Bulgaria , Método Doble Ciego , Femenino , Humanos , Lactobacillus , Masculino , Persona de Mediana Edad , Circunferencia de la Cintura/efectos de los fármacos
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4051-4054, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-33018888

RESUMEN

The purpose of this study was to discriminate between left- and right-hand motor imagery tasks. We recorded the brain signals from two participants using a fNIRS system and compared different feature extraction (mean, peak, minimum, skewness and kurtosis) and classification techniques (linear (LDA) and quadratic discriminant analysis (QDA), support vector machine (SVM), logistic regression, K-nearest-neighbor (KNN), and neural networks with Levenberg-Marquardt (LMA), Bayesian Regularization (BRANN) and Scaled Conjugate Gradient (SCGA) training algorithms). The results showed poor classification accuracies (<; 58%) when skewness and kurtosis were used. When mean, peak, and minimum were used as features, QDA, SVM and KNN produced higher classification accuracies relative to LDA and logistic regression. Overall, BRANN led to the highest accuracies (>98%) when mean, peak and minimum were used as features.


Asunto(s)
Interfaces Cerebro-Computador , Teorema de Bayes , Análisis Discriminante , Humanos , Imágenes en Psicoterapia , Espectroscopía Infrarroja Corta
5.
Sci Rep ; 9(1): 5291, 2019 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-30923355

RESUMEN

Voltage-gated sodium channels (VGSC) are transmembrane proteins that generate an action potential in excitable cells and play an essential role in neuronal signaling. Since VGSCs play a crucial role in nerve transmission they have become primary targets for a broad range of commercial insecticides. RNA interference (RNAi) is a valuable reverse genetics tool used in functional genomics, but recently, it has also shown promise as a novel agent that could be used to control agricultural insect pests. In this study, we targeted the VGSC (MpNav) gene in the peach-potato aphid Myzus persicae, by oral feeding of artificial diets mixed with dsRNAs. Knock-down of MpNav gene expression caused up to 65% mortality in 3rd instar nymphs. Moreover, significantly lower fecundity and longevity was observed in adult aphids that had been fed with dsMpNav solution at the nymphal stage. Analysis of gene expression by qRT-PCR indicated that the aphid mortality rates and the lowered fecundity and longevity were attributable to the down-regulation of MpNav by RNAi. Taken together, our results show that MpNav is a viable candidate target gene for the development of an RNAi-based bio-aphicide.


Asunto(s)
Áfidos/genética , Agentes de Control Biológico , Interferencia de ARN , ARN Bicatenario/genética , Canales de Sodio Activados por Voltaje/genética , Animales , Producción de Cultivos , Fertilidad/genética , Técnicas de Silenciamiento del Gen , Genes de Insecto , Longevidad/genética , Prunus persica/parasitología , Genética Inversa , Solanum tuberosum/parasitología , Factores de Tiempo
6.
Acute Med ; 17(4): 232-235, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30882108

RESUMEN

A previously fit and well 19 year old male presents with a progressive ataxic - sensory neuropathy worsening over 2 - 3 weeks. History and investigations revealed extensive recreational use of nitrous oxide resulting in functional B12 deficiency and consequent subacute combined degeneration of the cord. Abstinence and B12 supplementation resulted in a rapid and full neurological recovery. This case report highlights the importance of considering nitrous oxide abuse in the differential diagnosis of atypical neurological symptoms and signs, and emphasizes the possibility of good clinical outcomes with treatment.


Asunto(s)
Ataxia , Óxido Nitroso , Deficiencia de Vitamina B 12 , Ataxia/inducido químicamente , Diagnóstico Diferencial , Humanos , Masculino , Óxido Nitroso/efectos adversos , Vitamina B 12 , Deficiencia de Vitamina B 12/inducido químicamente , Adulto Joven
7.
Am J Physiol Cell Physiol ; 310(3): C193-204, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26538090

RESUMEN

The extracellular calcium-sensing receptor CaSR is expressed in blood vessels where its role is not completely understood. In this study, we tested the hypothesis that the CaSR expressed in vascular smooth muscle cells (VSMC) is directly involved in regulation of blood pressure and blood vessel tone. Mice with targeted CaSR gene ablation from vascular smooth muscle cells (VSMC) were generated by breeding exon 7 LoxP-CaSR mice with animals in which Cre recombinase is driven by a SM22α promoter (SM22α-Cre). Wire myography performed on Cre-negative [wild-type (WT)] and Cre-positive (SM22α)CaSR(Δflox/Δflox) [knockout (KO)] mice showed an endothelium-independent reduction in aorta and mesenteric artery contractility of KO compared with WT mice in response to KCl and to phenylephrine. Increasing extracellular calcium ion (Ca(2+)) concentrations (1-5 mM) evoked contraction in WT but only relaxation in KO aortas. Accordingly, diastolic and mean arterial blood pressures of KO animals were significantly reduced compared with WT, as measured by both tail cuff and radiotelemetry. This hypotension was mostly pronounced during the animals' active phase and was not rescued by either nitric oxide-synthase inhibition with nitro-l-arginine methyl ester or by a high-salt-supplemented diet. KO animals also exhibited cardiac remodeling, bradycardia, and reduced spontaneous activity in isolated hearts and cardiomyocyte-like cells. Our findings demonstrate a role for CaSR in the cardiovascular system and suggest that physiologically relevant changes in extracellular Ca(2+) concentrations could contribute to setting blood vessel tone levels and heart rate by directly acting on the cardiovascular CaSR.


Asunto(s)
Presión Sanguínea , Señalización del Calcio , Calcio/metabolismo , Hipotensión/metabolismo , Músculo Liso Vascular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Vasoconstricción , Vasodilatación , Animales , Aorta/metabolismo , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/genética , Bradicardia/genética , Bradicardia/metabolismo , Bradicardia/fisiopatología , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/genética , Relación Dosis-Respuesta a Droga , Predisposición Genética a la Enfermedad , Frecuencia Cardíaca , Hipotensión/genética , Hipotensión/fisiopatología , Arterias Mesentéricas/metabolismo , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/fisiopatología , Miocitos Cardíacos/metabolismo , Fenotipo , Receptores Sensibles al Calcio , Receptores Acoplados a Proteínas G/deficiencia , Receptores Acoplados a Proteínas G/genética , Vasoconstricción/efectos de los fármacos , Vasoconstricción/genética , Vasoconstrictores/farmacología , Vasodilatación/efectos de los fármacos , Vasodilatación/genética , Vasodilatadores/farmacología , Remodelación Ventricular
8.
Proc Biol Sci ; 282(1814)2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26311670

RESUMEN

Non-lethal parasite infections are common in wildlife, but there is little information on their clinical consequences. Here, we pair infection data from a ubiquitous soil-transmitted helminth, the whipworm (genus Trichuris), with activity data from a habituated group of wild red colobus monkeys (Procolobus rufomitratus tephrosceles) in Kibale National Park, Uganda. We use mixed-effect models to examine the relationship between non-lethal parasitism and red colobus behaviour. Our results indicate that red colobus increased resting and decreased more energetically costly behaviours when shedding whipworm eggs in faeces. Temporal patterns of behaviour also changed, with individuals switching behaviour less frequently when whipworm-positive. Feeding frequency did not differ, but red colobus consumption of bark and two plant species from the genus Albizia, which are used locally in traditional medicines, significantly increased when animals were shedding whipworm eggs. These results suggest self-medicative plant use, although additional work is needed to verify this conclusion. Our results indicate sickness behaviours, which are considered an adaptive response by hosts during infection. Induction of sickness behaviour in turn suggests that these primates are clinically sensitive to non-lethal parasite infections.


Asunto(s)
Conducta Animal , Colobinae/parasitología , Conducta de Enfermedad/fisiología , Tricuriasis/veterinaria , Trichuris , Albizzia , Animales , Colobinae/psicología , Dieta/veterinaria , Heces/parasitología , Medicinas Tradicionales Africanas , Corteza de la Planta , Descanso , Tricuriasis/patología , Tricuriasis/psicología , Uganda
9.
Clin Exp Dermatol ; 39(8): 861-7, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25394292

RESUMEN

Following on from Part 1 of the series (regional nerve blocks for the face and scalp), we guide the clinician through the anatomy and cutaneous innervation of the digits, wrist and ankle, providing a practical step-by-step guide to regional nerve blockade of these areas.


Asunto(s)
Anestesia Local/métodos , Anestésicos Locales/administración & dosificación , Tobillo , Dedos , Bloqueo Nervioso/métodos , Dedos del Pie , Muñeca , Tobillo/inervación , Dermatología/métodos , Dedos/inervación , Humanos , Guías de Práctica Clínica como Asunto , Dedos del Pie/inervación , Muñeca/inervación
10.
Clin Exp Dermatol ; 39(7): 777-84, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25214404

RESUMEN

The aim of this two-part series is to provide an up-to-date review of essential regional nerve blocks for dermatological practice. In Part 1, we give a concise overview of local anaesthetics and their potential complications, as well as the relevant anatomy and cutaneous innervation of the face and scalp. This culminates in a step-by-step practical guide to performing each nerve block.


Asunto(s)
Anestesia Local/métodos , Anestésicos Locales/administración & dosificación , Cara , Bloqueo Nervioso/métodos , Cuero Cabelludo , Dermatología/métodos , Cara/inervación , Humanos , Cuero Cabelludo/inervación
11.
Gait Posture ; 39(4): 1074-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24556467

RESUMEN

BACKGROUND: Hereditary spastic paraparesis (HSP) is a group of neurological disorders characterised by slowly progressive increasing muscle tone, predominantly in the lower limbs, with relatively preserved power. This leads to progressive difficulties in motor control and walking. OBJECTIVE: The purpose of this study was to evaluate the effectiveness of hydrotherapy treatment when used as a means to increase locomotor function in individuals with late onset HSP. This paper discusses the analysis of the effect on gait characteristics. METHODS: Nine people with HSP were asked to participate in pre- and post-hydrotherapy gait analyses. Ground reaction force and motion trajectories were recorded and used to calculate spatiotemporal gait parameters, joint angles and moments. RESULTS: The normalised joint kinematics and kinetics profile revealed that the biomechanics of people with HSP were similar to that of controls for most of the joints, but with lower range of motion. Walking speed increased significantly (11%) after the course of hydrotherapy. Though part of this was achieved through increased ROM there was also a further increase in hip internal rotation and in peak hip extension moment. CONCLUSIONS: Although participants had increased walking speed and step length, it appears that hydrotherapy increases the ability to perform compensatory strategies rather than resulting in a more typical kinematic and kinetic approach.


Asunto(s)
Trastornos Neurológicos de la Marcha/terapia , Hidroterapia , Paraplejía Espástica Hereditaria/fisiopatología , Análisis de Varianza , Fenómenos Biomecánicos/fisiología , Estudios de Casos y Controles , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Articulaciones/fisiopatología , Extremidad Inferior/fisiopatología , Rango del Movimiento Articular/fisiología , Rotación , Caminata/fisiología
12.
Br J Cancer ; 97(4): 464-71, 2007 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-17653074

RESUMEN

The aim of this phase II study was to assess the feasibility and efficacy of a specific three-dimensional conformal radiotherapy technique with concurrent continuous infusion of 5-fluorouracil (CI 5FU) sandwiched between gemcitabine chemotherapy in patients with locally advanced pancreatic cancer. Patients with inoperable cancer in the pancreatic head or body without metastases were given gemcitabine at 1000 mg m(-2) weekly for 3 weeks followed by a 1-week rest and a 6-week period of radiotherapy and concurrent CI 5FU (200 mg m(-2) day(-1)). The defined target volume was treated to 54 Gy in 30 daily fractions of 1.8 Gy. After 4 weeks' rest, gemcitabine treatment was re-initiated for three cycles (days 1, 8, 15, q28). Forty-one patients were enrolled. At the end of radiotherapy, one patient (2.4%) had a complete response and four patients (9.6%) had a partial response; at the end of treatment, three patients (7.3%) had a complete response and two patients (4.9%) had a partial response. Median survival time was 11.7 months, median time to progression was 7.1 months, and median time to failure of local control was 11.9 months. The 1- and 2-year survival rates were 46.3 and 9.8%, respectively. Treatment-related grade 3 and 4 toxicities were reported by 16 (39.0%) and four (9.8%) patients, respectively. Sixteen out of 41 patients did not complete the planned treatment and nine due to disease progression. This approach to treatment of locally advanced pancreatic cancer is safe and promising, with good local control for a substantial proportion of patients, and merits testing in a randomised trial.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Desoxicitidina/análogos & derivados , Fluorouracilo/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Radioterapia Conformacional , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Quimioterapia Adyuvante/efectos adversos , Terapia Combinada/efectos adversos , Desoxicitidina/efectos adversos , Desoxicitidina/uso terapéutico , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Estudios de Factibilidad , Femenino , Fluorouracilo/efectos adversos , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Radioterapia Asistida por Computador/efectos adversos , Radioterapia Conformacional/efectos adversos , Análisis de Supervivencia , Resultado del Tratamiento , Gemcitabina
13.
Nature ; 445(7129): 757-60, 2007 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-17301791

RESUMEN

One of the biggest challenges for conservation biology is to provide conservation planners with ways to prioritize effort. Much attention has been focused on biodiversity hotspots. However, the conservation of evolutionary process is now also acknowledged as a priority in the face of global change. Phylogenetic diversity (PD) is a biodiversity index that measures the length of evolutionary pathways that connect a given set of taxa. PD therefore identifies sets of taxa that maximize the accumulation of 'feature diversity'. Recent studies, however, concluded that taxon richness is a good surrogate for PD. Here we show taxon richness to be decoupled from PD, using a biome-wide phylogenetic analysis of the flora of an undisputed biodiversity hotspot--the Cape of South Africa. We demonstrate that this decoupling has real-world importance for conservation planning. Finally, using a database of medicinal and economic plant use, we demonstrate that PD protection is the best strategy for preserving feature diversity in the Cape. We should be able to use PD to identify those key regions that maximize future options, both for the continuing evolution of life on Earth and for the benefit of society.


Asunto(s)
Biodiversidad , Evolución Biológica , Conservación de los Recursos Naturales/métodos , Fenómenos Fisiológicos de las Plantas , Efecto Invernadero , Datos de Secuencia Molecular , Filogenia , Plantas/clasificación , Plantas/genética , Plantas Medicinales/clasificación , Plantas Medicinales/genética , Plantas Medicinales/fisiología , Densidad de Población , Sudáfrica
14.
J Cell Sci ; 116(Pt 15): 3135-44, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12799416

RESUMEN

Phosphorus deficiency limits plant growth, and high-affinity phosphate transporters, of the Pht1 family, facilitate phosphate uptake and translocation. The family is subdivided into root specific, phosphate deprivation induced members and those also expressed in leaves. An antibody to StPT2, a potato root specific transporter, detected two bands (52 kDa and 30 kDa) on western blots of root plasma membrane extracts that were most intense in whole extracts from the root tip and slightly increased throughout the root in response to phosphate depletion. RT-PCR, using StPT2 specific primers, confirmed these findings. Low power confocal immunofluorescent images showed StPT2 expression mainly in the elongation zone at the root tip. By contrast, a vacuolar pyrophosphatase and a plasma membrane ATPase antibody labelled the whole root. High power images showed, by comparison with alpha-tubulin, cell wall and plasma membrane ATPase labelling, that StPT2 was in the epidermal plasma membrane and restricted to the apical surface. This is the first evidence of polar plasma membrane localisation of a plant nutrient transporter and is consistent with a role for StPT2 in phosphate capture and uptake.


Asunto(s)
Meristema/enzimología , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Solanum tuberosum/enzimología , Adenosina Trifosfatasas/metabolismo , Western Blotting , Membrana Celular/enzimología , Pared Celular/metabolismo , Microscopía Confocal , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tubulina (Proteína)/metabolismo
15.
Antimicrob Agents Chemother ; 45(11): 3242-5, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11600391

RESUMEN

Activities of HMR 3787 and RU 64399 were compared to those of three macrolides, telithromycin, and clindamycin against 175 Streptococcus pneumoniae isolates and 121 Streptococcus pyogenes isolates. HMR3787 and telithromycin were the most active compounds tested against pneumococci. Telithromycin and RU 64399 were equally active against macrolide-susceptible (MICs, 0.008 to 0.06 microg/ml) and -resistant S. pyogenes isolates, but HMR 3787 had lower MICs for ermB strains.


Asunto(s)
Antibacterianos/uso terapéutico , Cetólidos , Macrólidos , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pyogenes/efectos de los fármacos , Azitromicina/uso terapéutico , Claritromicina/uso terapéutico , Clindamicina/uso terapéutico , Resistencia a Medicamentos , Eritromicina/uso terapéutico , Pruebas de Sensibilidad Microbiana
16.
Endocrinology ; 140(3): 1392-8, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10067867

RESUMEN

In order to replicate a recently described murine model of Graves' disease, we immunized AKR/N (H-2k) mice i.p., every 2 weeks, with either a clone of fibroblasts expressing both the human TSH receptor (hTSHR) and murine major histocompatibility complex (MHC) class II molecules or with fibroblasts expressing the MHC class II molecules alone. Mice were bled, and their thyroid hormone levels measured, at 6, 12, and up to 18 weeks after the first immunization. Between 11-12 weeks after immunization, a significant number of mice began to die spontaneously and were found to have developed large goiters. Thirty to 40% of mice immunized with hTSHR transfected fibroblasts showed markedly increased serum T3 and T4 hormone levels by 12 weeks compared with controls, with the highest thyroid hormone levels being T3: 420 ng/dl (normal < 70) and T4: 16.5 microg/dl (normal < 5). The murine serum demonstrated the presence of antibodies to the TSHR, as evidenced by inhibition of labeled TSH binding to the hTSHR, and these sera had in vitro thyroid stimulating activity. Many of the hyperthyroid mouse exhibited weight loss and hyperactivity and, on examination, their thyroids had the histological features of thyroid hyperactivity including thyroid enlargement, thyroid cell hypertrophy, and colloid droplet formation--all consistent with Graves' disease. In contrast, a small number of mice (< 5%) developed hypothyroidism with low serum T4 levels and markedly increased TSH concentrations and evidence of thyroid hypoplasia. Both hyperthyroidism and hypothyroidism were successfully transferred to naive mice using ip cells of immunized mice. Surprisingly, hypothyroidism occurred in many recipient mice even after transfer from hyperthyroid donors. These results confirmed that immunization with naturally expressed hTSHR in mammalian cells was able to induce functional TSHR autoantibodies that either stimulated or blocked the mouse thyroid gland and induced hyperthyroidism or thyroid failure. Furthermore, both blocking and stimulating antibodies coexisted in the same mice as evidenced so clearly by the transfer of hypothyroidism from hyperthyroid mice. The addition of a Th2 adjuvant (pertussis toxin) caused approximately 50% of the animals to become hyperthyroid beginning early at 9 weeks, whereas a Th1 adjuvant (CFA) delayed the disease onset such that only 10% were hyperthyroid by 12 weeks. As with human autoimmune thyroid disease, the T cell control of this murine model may be critical and requires more extensive investigation.


Asunto(s)
Enfermedad de Graves/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Inmunización , Receptores de Tirotropina/inmunología , Animales , Formación de Anticuerpos , ADN Complementario/genética , Modelos Animales de Enfermedad , Femenino , Humanos , Células L , Masculino , Ratones , Pruebas de Función de la Tiroides , Transfección
17.
Biochem J ; 337 ( Pt 3): 373-7, 1999 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9895279

RESUMEN

The bisphosphonates (general structure PO3-R-PO3) competitively inhibit soluble and membrane-bound inorganic pyrophosphatases (PPases) with differing degrees of specificity. Aminomethylenebisphosphonate (AMBP; HC(PO3)2NH2) is a potent, specific inhibitor of the PPase of higher plant vacuoles (V-PPase). To explore the possibility of constructing photoactivatable probes from bisphosphonates to label the active site of V-PPase we analysed the effects of different analogues on the hydrolytic and proton pumping activity of the enzyme. Bisphosphonates with a range of structures inhibited competitively and the effects on PPi hydrolysis correlated with the effects on proton pumping. Low-molecular-mass bisphosphonates containing hydrophilic groups (alpha-NH2 or OH) were the most effective, suggesting that the catalytic site is in a restricted polar pocket. Bisphosphonates containing a benzene ring were less active but the introduction of a nitrogen atom into the ring increased activity. Compounds of the general formula NH2(CH2)nC(PO3)2OH were more inhibitory than compounds of the H(CH2)nC(PO3)2NH2, NH2(CH2)nC(PO3)2NH2 or OH(CH2)nC(PO3)2NH2 series, with activity decreasing as n increased. A nitrogen atom in the carbon chain increased activity but activity was decreased by the presence of an oxygen atom. An analogue with a ring attached via a four-carbon chain, which included an amide linkage and a hydroxy group on the alpha-carbon atom, inhibited competitively (Ki=62.0 microM), suggesting that it may be possible to design bisphosphonate inhibitors which contain a photoactivatable azido group for photoaffinity labelling of V-PPase active site.


Asunto(s)
Difosfonatos/farmacología , Inhibidores Enzimáticos/farmacología , Fabaceae/enzimología , Proteínas de Plantas/metabolismo , Plantas Medicinales , Pirofosfatasas/metabolismo , Sitios de Unión , Membrana Celular/metabolismo , Pirofosfatasa Inorgánica , Proteínas de Plantas/antagonistas & inhibidores , Pirofosfatasas/antagonistas & inhibidores , Solubilidad , Relación Estructura-Actividad , Especificidad por Sustrato
18.
Drug Chem Toxicol ; 21(2): 163-79, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9598298

RESUMEN

The toxicity profile of the antidepressant drug sertraline was determined in a series of preclinical studies in mice, rats, rabbits and dogs. Acute, subchronic, reproductive, chronic and carcinogenicity studies were conducted by the oral route. The highest doses tested in these studies were the maximum tolerated doses based on clinical signs, decreased food consumption, body weight effects, organ weight changes or clinical/anatomical pathology findings. Genetic toxicity studies were also performed. The liver was identified as a target organ in the mouse, rat and dog. The observed liver findings were consistent with hepatic xenobiotic-metabolizing enzyme induction and included hepatomegaly, hepatocellular hypertrophy, slightly increased serum transaminase activity and proliferation of smooth endoplasmic reticulum. Hepatocellular fatty change, a minimal toxic effect, was seen in mice and rats. There was no teratogenicity in studies conducted at maternally toxic doses in rats and rabbits. Decreased neonatal survival and growth observed in these studies have been previously reported in reproduction studies with other serotonin reuptake inhibitors. Sertraline was not genotoxic in an extensive battery of tests. Carcinogenicity tests were negative in rats, while benign liver tumors were slightly increased in drugtreated male mice. Liver tumors were considered secondary to the enzyme inducing potential of sertraline and not indicative of human risk.


Asunto(s)
1-Naftilamina/análogos & derivados , Antidepresivos/toxicidad , Inhibidores Selectivos de la Recaptación de Serotonina/toxicidad , 1-Naftilamina/administración & dosificación , 1-Naftilamina/toxicidad , Administración Oral , Animales , Antidepresivos/administración & dosificación , Pruebas de Carcinogenicidad , Enfermedad Hepática Inducida por Sustancias y Drogas , Perros , Evaluación Preclínica de Medicamentos , Inducción Enzimática/efectos de los fármacos , Femenino , Inyecciones Intraperitoneales , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/patología , Masculino , Ratones , Pruebas de Mutagenicidad , Embarazo , Efectos Tardíos de la Exposición Prenatal , Conejos , Ratas , Reproducción/efectos de los fármacos , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Sertralina , Especificidad de la Especie
19.
Drug Chem Toxicol ; 21(4): 521-37, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10048942

RESUMEN

The toxicity profile of the antidepressant drug sertraline was determined in a series of preclinical studies in mice, rats, rabbits and dogs. Acute, subchronic, reproductive, chronic and carcinogenicity studies were conducted by the oral route. The highest doses tested in these studies were the maximum tolerated doses based on clinical signs, decreased food consumption, body weight effects, organ weight changes or clinical/anatomical pathology findings. Genetic toxicity studies were also performed. The liver was identified as a target organ in the mouse, rat and dog. The observed liver findings were consistent with hepatic xenobiotic-metabolizing enzyme induction and included hepatomegaly, hepatocellular hypertrophy, slightly increased serum transaminase activity and proliferation of smooth endoplasmic reticulum. Hepatocellular fatty change, a minimal toxic effect, was seen in mice and rats. There was no teratogenicity in studies conducted at maternally toxic doses in rats and rabbits. Decreased neonatal survival and growth observed in these studies have been previously reported in reproduction studies with serotonin reuptake inhibitors. Sertraline was not genotoxic in an extensive battery of tests. Carcinogenicity tests were negative in rats, while benign liver tumors were slightly increased in drug-treated male mice. Liver tumors were considered secondary to the enzyme inducing potential of sertraline and not indicative of human risk.


Asunto(s)
Sertralina/toxicidad , Adenoma/inducido químicamente , Animales , Conducta Animal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Embrión de Mamíferos/efectos de los fármacos , Desarrollo Embrionario y Fetal , Femenino , Fertilidad/efectos de los fármacos , Dosificación Letal Mediana , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/crecimiento & desarrollo , Pruebas de Función Hepática , Masculino , Ratones , Debilidad Muscular/inducido químicamente , Tamaño de los Órganos/efectos de los fármacos , Conejos , Ratas , Ratas Long-Evans , Ratas Sprague-Dawley , Pruebas de Toxicidad
20.
J Cell Biol ; 139(6): 1545-52, 1997 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-9396759

RESUMEN

The sodium/potassium pump, Na+,K+-ATPase, is generally understood to function as a heterodimer of two subunits, a catalytic alpha subunit and a noncatalytic, glycosylated beta subunit. Recently, a putative third subunit, the gamma subunit, was cloned. This small protein (6.5 kD) coimmunoprecipitates with the alpha and beta subunits and is closely associated with the ouabain binding site on the holoenzyme, but its function is unknown. We have investigated the expression of the gamma subunit in preimplantation mouse development, where Na+, K+-ATPase plays a critical role as the driving force for blastocoel formation (cavitation). Using reverse transcriptase-polymerase chain reaction, we demonstrated that the gamma subunit mRNA accumulates continuously from the eight-cell stage onward and that it cosediments with polyribosomes from its time of first appearance. Confocal immunofluorescence microscopy revealed that the gamma subunit itself accumulates and is localized at the blastomere surfaces up to the blastocyst stage. In contrast with the alpha and beta subunits, the gamma subunit is not concentrated in the basolateral surface of the polarized trophectoderm layer, but is strongly expressed at the apical surface as well. When embryos were treated with antisense oligodeoxynucleotide complementary to the gamma subunit mRNA, ouabain-sensitive K+ transport (as indicated by 86Rb+ uptake) was reduced and cavitation delayed. However, Na+, K+-ATPase enzymatic activity was unaffected as determined by a direct phosphorylation assay ("back door" phosphorylation) applied to plasma membrane preparations. These results indicate that the gamma subunit, although not an integral component of Na+,K+-ATPase, is an important determinant of active cation transport and that, as such, its embryonic expression is essential for blastocoel formation in the mouse.


Asunto(s)
Blastocisto/citología , Blastocisto/fisiología , Regulación del Desarrollo de la Expresión Génica , ATPasa Intercambiadora de Sodio-Potasio/biosíntesis , Transcripción Genética , Equilibrio Hidroelectrolítico , Animales , Secuencia de Bases , Blastocisto/enzimología , Blastómeros/citología , Blastómeros/enzimología , Blastómeros/fisiología , Desarrollo Embrionario y Fetal , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Sustancias Macromoleculares , Masculino , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Oligonucleótidos Antisentido/farmacología , Polirribosomas/metabolismo , ARN Mensajero/biosíntesis , ATPasa Intercambiadora de Sodio-Potasio/química , Tionucleótidos
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