Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Semin Immunol ; 65: 101672, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36469987

RESUMEN

Treatment of tuberculosis (TB) involves the administration of anti-mycobacterial drugs for several months. The emergence of drug-resistant strains of Mycobacterium tuberculosis (Mtb, the causative agent) together with increased disease severity in people with co-morbidities such as diabetes mellitus and HIV have hampered efforts to reduce case fatality. In severe disease, TB pathology is largely attributable to over-exuberant host immune responses targeted at controlling bacterial replication. Non-resolving inflammation driven by host pro-inflammatory mediators in response to high bacterial load leads to pulmonary pathology including cavitation and fibrosis. The need to improve clinical outcomes and reduce treatment times has led to a two-pronged approach involving the development of novel antimicrobials as well as host-directed therapies (HDT) that favourably modulate immune responses to Mtb. HDT strategies incorporate aspects of immune modulation aimed at downregulating non-productive inflammatory responses and augmenting antimicrobial effector mechanisms to minimise pulmonary pathology and accelerate symptom resolution. HDT in combination with existing antimycobacterial agents offers a potentially promising strategy to improve the long-term outcome for TB patients. In this review, we describe components of the host immune response that contribute to inflammation and tissue damage in pulmonary TB, including cytokines, matrix metalloproteinases, lipid mediators, and neutrophil extracellular traps. We then proceed to review HDT directed at these pathways.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Humanos , Antituberculosos/uso terapéutico , Tuberculosis Pulmonar/tratamiento farmacológico , Inflamación
2.
Sensors (Basel) ; 23(11)2023 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-37300053

RESUMEN

The requirement for alternatives in roll-to-roll (R2R) processing to expand thin film inspection in wider substrates at lower costs and reduced dimensions, and the need to enable newer control feedback options for these types of processes, represents an opportunity to explore the applicability of newer reduced-size spectrometers sensors. This paper presents the hardware and software development of a novel low-cost spectroscopic reflectance system using two state-of-the-art sensors for thin film thickness measurements. The parameters to enable the thin film measurements using the proposed system are the light intensity for two LEDs, the microprocessor integration time for both sensors and the distance from the thin film standard to the device light channel slit for reflectance calculations. The proposed system can deliver better-fit errors compared with a HAL/DEUT light source using two methods: curve fitting and interference interval. By enabling the curve fitting method, the lowest root mean squared error (RMSE) obtained for the best combination of components was 0.022 and the lowest normalised mean squared error (MSE) was 0.054. The interference interval method showed an error of 0.09 when comparing the measured with the expected modelled value. The proof of concept in this research work enables the expansion of multi-sensor arrays for thin film thickness measurements and the potential application in moving environments.

3.
Sensors (Basel) ; 23(8)2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37112318

RESUMEN

Within aerospace and automotive manufacturing, the majority of quality assurance is through inspection or tests at various steps during manufacturing and assembly. Such tests do not tend to capture or make use of process data for in-process inspection and certification at the point of manufacture. Inspection of the product during manufacturing can potentially detect defects, thus allowing consistent product quality and reducing scrappage. However, a review of the literature has revealed a lack of any significant research in the area of inspection during the manufacturing of terminations. This work utilises infrared thermal imaging and machine learning techniques for inspection of the enamel removal process on Litz wire, typically used for aerospace and automotive applications. Infrared thermal imaging was utilised to inspect bundles of Litz wire containing those with and without enamel. The temperature profiles of the wires with or without enamel were recorded and then machine learning techniques were utilised for automated inspection of enamel removal. The feasibility of various classifier models for identifying the remaining enamel on a set of enamelled copper wires was evaluated. A comparison of the performance of classifier models in terms of classification accuracy is presented. The best model for enamel classification accuracy was the Gaussian Mixture Model with expectation maximisation; it achieved a training accuracy of 85% and enamel classification accuracy of 100% with the fastest evaluation time of 1.05 s. The support vector classification model achieved both the training and enamel classification accuracy of more than 82%; however, it suffered the drawback of a higher evaluation time of 134 s.

4.
Sociol Health Illn ; 42(6): 1259-1276, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32436235

RESUMEN

Caste, a stratifying axis of the Indian society, is associated with wealth and health. However, to what extent caste-based health inequality is explained by wealth disparities, is not clear. Therefore, we aimed to examine the caste-based differences in anaemia (haemoglobin < 11 gm/dl) and self-reported sickness absenteeism in schoolchildren and the mediating role of economic disparity. Students (n = 1764) were surveyed from 54 government schools of Dhenkanal and Angul, Odisha state. Socioeconomic data, anaemia and absenteeism were recorded. The relative risks of anaemia among Scheduled Tribe (least advantaged) and Scheduled Caste (second least advantaged) students were 1.19 (95% CI: 1.08, 1.26) and 1.13 (1.03, 1.20), respectively, as compared to students of the most advantaged caste and that for sickness absenteeism were 2.78 (2.03, 3.82) and 2.84 (2.13, 3.78); p < 0.05, with marginal attenuation when controlled for inter-caste economic disparities. Caste had an independent effect on anaemia and sickness absenteeism in school children, unexplained by inter-caste economic disparities.


Asunto(s)
Disparidades en el Estado de Salud , Clase Social , Niño , Humanos , India/epidemiología , Población Rural , Instituciones Académicas , Factores Socioeconómicos
6.
Org Biomol Chem ; 13(15): 4438-48, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25764985

RESUMEN

An efficient and scalable synthesis of various enantiopure 1,3- disubstituted isoindolines is reported. The base catalyzed nucleophilic fragmentation of a rigid overbred template is established with various substrates to afford the corresponding 1,3-disubstituted isoindoline ester, amide, thioate, 1,3-amino alcohol and isoindolylcarboxylic acid. The crucial rigid overbred template is synthesized in an optically pure form in multigram scale by asymmetric desymmetrization of the corresponding meso compound.


Asunto(s)
Isoindoles/síntesis química , Amidas/síntesis química , Amidas/química , Amino Alcoholes/síntesis química , Amino Alcoholes/química , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/química , Catálisis , Ésteres/síntesis química , Ésteres/química , Isoindoles/química , Modelos Moleculares , Estereoisomerismo , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/química
7.
Int J Infect Dis ; 141S: 106988, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38417613

RESUMEN

The World Health Organization's aim to end the global tuberculosis (TB) epidemic by 2050 cannot be achieved without taking measures to identify people with asymptomatic Mycobacterium tuberculosis (Mtb) infection and offer them an intervention to reduce the risk of disease progression, such as preventive antimicrobial therapy. Implementation of this strategy is limited by the fact that existing tests for Mtb infection, which use immunosensitization to Mtb-specific antigens as a proxy for infection, have low positive predictive value for progression to TB. A blood test that detects Mtb deoxyribonucleic acid (DNA) could allow preventive therapy to be targeted at individuals with microbiological evidence of persistent infection. In this review, we summarize recent advances in the development of molecular microbial blood tests for Mtb infection and discuss potential explanations for discordance between their results and those of immunodiagnostic tests in adults with recent exposure to an infectious index case. We also present a roadmap for further development of molecular microbial blood tests for Mtb infection, and highlight the potential for research in this area to provide novel insights into the biology of Mtb infection and yield new tools to support efforts to control the global TB epidemic.


Asunto(s)
Tuberculosis Latente , Mycobacterium tuberculosis , Tuberculosis , Adulto , Humanos , Tuberculosis/microbiología , Tuberculosis Latente/microbiología , Mycobacterium tuberculosis/genética , Valor Predictivo de las Pruebas , Pruebas Hematológicas
8.
Cochrane Database Syst Rev ; (6): CD008710, 2013 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-23740537

RESUMEN

BACKGROUND: Subarachnoid haemorrhage may result in seizures both acutely and in the longer term. The use of antiepileptic drugs (AEDs) in the primary and secondary prevention of seizures after subarachnoid haemorrhage is uncertain, and there is currently no consensus on treatment. OBJECTIVES: To assess the effects of AEDs for the primary and secondary prevention of seizures after subarachnoid haemorrhage. SEARCH METHODS: We searched the Cochrane Epilepsy Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 1) in The Cochrane Library, and MEDLINE (1946 to 12th March 2013). We checked the reference lists of articles retrieved from these searches. SELECTION CRITERIA: We considered all randomised and quasi-randomised controlled trials in which patients were assigned to a treatment (one or more AEDs) or placebo. DATA COLLECTION AND ANALYSIS: Two review authors (RM and JK) independently screened and assessed the methodological quality of the studies. If studies were included, one author extracted the data and the other checked it. MAIN RESULTS: No relevant studies were found. AUTHORS' CONCLUSIONS: There was no evidence to support or refute the use of antiepileptic drugs for the primary or secondary prevention of seizures related to subarachnoid haemorrhage. Well-designed randomised controlled trials are urgently needed to guide clinical practice.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Prevención Secundaria/métodos , Convulsiones/prevención & control , Hemorragia Subaracnoidea/complicaciones , Humanos , Convulsiones/etiología
9.
PLoS One ; 18(3): e0281559, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36972254

RESUMEN

BACKGROUND: The tuberculin skin test is commonly used to diagnose latent tuberculosis infection (LTBI) in resource-limited settings, but its specificity is limited by factors including cross-reactivity with BCG vaccine and environmental mycobacteria. Interferon-gamma release assays (IGRA) overcome this problem by detecting M. tuberculosis complex-specific responses, but studies to determine risk factors for IGRA-positivity in high TB burden settings are lacking. METHODS: We conducted a cross-sectional study to determine factors associated with a positive IGRA by employing the QuantiFERON-TB® Gold-plus (QFT Plus) assay in a cohort of asymptomatic adult TB contacts in Kampala, Uganda. Multivariate logistic regression analysis with forward stepwise logit function was employed to identify independent correlates of QFT Plus-positivity. RESULTS: Of the 202 participants enrolled, 129/202 (64%) were female, 173/202 (86%) had a BCG scar, and 67/202 (33%) were HIV-infected. Overall, 105/192 (54%, 95% CI 0.48-0.62) participants had a positive QFT Plus result. Increased risk of QFT-Plus positivity was independently associated with casual employment/unemployment vs. non-casual employment (adjusted odds ratio (aOR) 2.18, 95% CI 1.01-4.72), a family vs. non-family relation to the index patient (aOR 2.87, 95% CI 1.33-6.18), living in the same vs. a different house as the index (aOR 3.05, 95% CI 1.28-7.29), a higher body mass index (BMI) (aOR per additional kg/m2 1.09, 95% CI 1.00-1.18) and tobacco smoking vs. not (aOR 2.94, 95% CI 1.00-8.60). HIV infection was not associated with QFT-Plus positivity (aOR 0.91, 95% CI 0.42-1.96). CONCLUSION: Interferon Gamma Release Assay positivity in this study population was lower than previously estimated. Tobacco smoking and BMI were determinants of IGRA positivity that were previously unappreciated.


Asunto(s)
Infecciones por VIH , Tuberculosis Latente , Tuberculosis , Humanos , Adulto , Femenino , Masculino , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/epidemiología , Estudios Transversales , Uganda/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Ensayos de Liberación de Interferón gamma , Prueba de Tuberculina , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología
10.
Food Nutr Bull ; 44(2): 79-87, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37165677

RESUMEN

BACKGROUND: Iron-deficiency anemia among school-aged children is widespread in India. The efficacy of micronutrient and iron fortified school-served meals in reducing iron deficiency anemia has been demonstrated in randomized controlled trials in other parts of the globe. The current study evaluates its effectiveness in real-world Indian settings. METHODS: Mid-day-Meal (MDM) programme provides free lunch to students of grades 1 to 8 in all public-funded Indian schools. An implementation research project fortified MDM of all public schools of 4 out of 8 sub-districts ("blocks") of Dhenkanal district of Odisha state with fortified rice kernel (FRK). All the schools of the other 4 blocks fortified with micronutrient powders (MNP)-both FRK and MNP containing equal amounts of supplementary iron and other micronutrients. Schools of 4 matched blocks of neighboring nonimplementing Angul district served as control. Cross-sectional representative samples of students were drawn from the 3 arms, before and after intervention (n = 1764 and n = 1640 respectively). Pre-post changes in anemia prevalence and hemoglobin levels were estimated in the sampled children using difference-in-difference analysis after controlling for inter-arm differences in socioeconomic status, and iron and deworming tablet consumptions. RESULTS: Factoring in pre-post changes in control and adjusting for potential confounders, the proportion of children without anemia and mean hemoglobin improved by 1.93 (1.38, 2.24, P < .001) times and 0.24 (-0.03, 0.51, P = .083) g/dL in MNP; and 1.63 (1.18, 2.24, P = .002) times and 0.18 (-0.09, 0.45, P = .198) g/dL in FRK arms. CONCLUSIONS: Fortified MDM could effectively improve anemia status among Indian school-aged children under real-world conditions.


Asunto(s)
Anemia Ferropénica , Anemia , Oligoelementos , Humanos , Niño , Hierro , Estudios Transversales , Alimentos Fortificados , Anemia/epidemiología , Anemia/prevención & control , Micronutrientes , Hemoglobinas , Comidas , Anemia Ferropénica/epidemiología , Anemia Ferropénica/prevención & control
11.
PLoS One ; 18(11): e0294330, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37963137

RESUMEN

BACKGROUND: Ageing is associated with changes in body composition including an overall reduction in muscle mass and a proportionate increase in fat mass. Sarcopenia is characterised by losses in both muscle mass and strength. Body composition and muscle strength are at least in part genetically determined, consequently polymorphisms in pathways important in muscle biology (e.g., the activin/myostatin signalling pathway) are hypothesised to contribute to the development of sarcopenia. METHODS: We compared regional body composition measured by DXA with genotypes for two polymorphisms (rs10783486, minor allele frequency (MAF) = 0.26 and rs2854464, MAF = 0.26) in the activin 1B receptor (ACVR1B) determined by PCR in a cross-sectional analysis of DNA from 110 older individuals with sarcopenia from the LACE trial. RESULTS: Neither muscle mass nor strength showed any significant associations with either genotype in this cohort. Initial analysis of rs10783486 showed that males with the AA/AG genotype were taller than GG males (174±7cm vs 170±5cm, p = 0.023) and had higher arm fat mass, (median higher by 15%, p = 0.008), and leg fat mass (median higher by 14%, p = 0.042). After correcting for height, arm fat mass remained significantly higher (median higher by 4% padj = 0.024). No associations (adjusted or unadjusted) were seen in females. Similar analysis of the rs2854464 allele showed a similar pattern with the presence of the minor allele (GG/AG) being associated with greater height (GG/AG = 174±7 cm vs AA = 170 ±5cm, p = 0.017) and greater arm fat mass (median higher by 16%, p = 0.023). Again, the difference in arm fat remained after correction for height. No similar associations were seen in females analysed alone. CONCLUSION: These data suggest that polymorphic variation in the ACVR1B locus could be associated with body composition in older males. The activin/myostatin pathway might offer a novel potential target to prevent fat accumulation in older individuals.


Asunto(s)
Sarcopenia , Masculino , Femenino , Humanos , Anciano , Sarcopenia/genética , Miostatina , Receptores de Activinas , Estudios Transversales , Composición Corporal/genética , Activinas/genética , Músculo Esquelético
12.
PLoS One ; 18(10): e0292402, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37862321

RESUMEN

BACKGROUND: Angiotensin II (AII), has been suggested to promote muscle loss. Reducing AII synthesis, by inhibiting angiotensin converting enzyme (ACE) activity has been proposed as a method to inhibit muscle loss. The LACE clinical trial was designed to determine whether ACE inhibition would reduce further muscle loss in individuals with sarcopenia but suffered from low recruitment and returned a negative result. Polymorphic variation in the ACE promoter (I/D alleles) has been associated with differences in ACE activity and muscle physiology in a range of clinical conditions. This aim of this analysis was to determine whether I/D polymorphic variation is associated with muscle mass, strength, in sarcopenia or contributed to the lack of response to treatment in the LACE study. METHODS: Sarcopenic individuals were recruited into a 2x2 factorial multicentre double-blind study of the effects of perindopril and/or leucine versus placebo on physical performance and muscle mass. DNA extracted from blood samples (n = 130 72 women and 58 men) was genotyped by PCR for the ACE I/D polymorphism. Genotypes were then compared with body composition measured by DXA, hand grip and quadriceps strength before and after 12 months' treatment with leucine and/or perindopril in a cross-sectional analysis of the influence of genotype on these variables. RESULTS: Allele frequencies for the normal UK population were extracted from 13 previous studies (I = 0.473, D = 0.527). In the LACE cohort the D allele was over-represented (I = 0.412, D = 0.588, p = 0.046). This over-representation was present in men (I = 0.353, D = 0.647, p = 0.010) but not women (I = 0.458, D = 0.532, p = 0.708). In men but not women, individuals with the I allele had greater leg strength (II/ID = 18.00 kg (14.50, 21.60) vs DD = 13.20 kg (10.50, 15.90), p = 0.028). Over the 12 months individuals with the DD genotype increased in quadriceps strength but those with the II or ID genotype did not. Perindopril did not increase muscle strength or mass in any polymorphism group relative to placebo. CONCLUSION: Our results suggest that although ACE genotype was not associated with response to ACE inhibitor therapy in the LACE trial population, sarcopenic men with the ACE DD genotype may be weaker than those with the ACE I/D or II genotype.


Asunto(s)
Sarcopenia , Masculino , Humanos , Femenino , Anciano , Sarcopenia/tratamiento farmacológico , Sarcopenia/genética , Perindopril/uso terapéutico , Peptidil-Dipeptidasa A/genética , Estudios Transversales , Leucina , Fuerza de la Mano , Genotipo , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico
13.
J Cachexia Sarcopenia Muscle ; 13(2): 858-871, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35174663

RESUMEN

BACKGROUND: This trial aimed to determine the efficacy of leucine and/or perindopril in improving physical function in older people with sarcopenia. METHODS: Placebo-controlled, parallel group, double-blind, randomized two-by-two factorial trial. We recruited adults aged ≥ 70 years with sarcopenia, defined as low gait speed (<0.8 m/s on 4 m walk) and/or low handgrip strength (women < 20 kg, men < 30 kg) plus low muscle mass (using sex and body mass index category-specific thresholds derived from normative UK BioBank data) from 14 UK centres. Eligible participants were randomized to perindopril 4 mg or placebo, and to oral leucine powder 2.5 g or placebo thrice daily. The primary outcome was the between-group difference in the short physical performance battery (SPPB) score over 12-month follow-up by repeated-measures mixed models. Results were combined with existing systematic reviews using random-effects meta-analysis to derive summary estimates of treatment efficacy. RESULTS: We screened 320 people and randomized 145 participants compared with an original target of 440 participants. For perindopril [n = 73, mean age 79 (SD 6), female sex 39 (53%), mean SPPB 7.1 (SD 2.3)] versus no perindopril [n = 72, mean age 79 (SD 6), female sex 39 (54%), mean SPPB 6.9 (SD 2.4)], median adherence to perindopril was lower (76% vs. 96%; P < 0.001). Perindopril did not improve the primary outcome [adjusted treatment effect -0.1 points (95%CI -1.2 to 1.0), P = 0.89]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.4 kg (95%CI -1.1 to 0.3), P = 0.27]. More adverse events occurred in the perindopril group (218 vs. 165), but falls rates were similar. For leucine [n = 72, mean age 78 (SD 6), female sex 38 (53%), mean SPPB 7.0 (SD 2.1)] versus no leucine [n = 72, mean age 79 (SD 6), female sex 40 (55%), mean SPPB 7.0 (SD 2.5)], median adherence was the same in both groups (76% vs. 76%; P = 0.99). Leucine did not improve the primary outcome [adjusted treatment effect 0.1 point (95%CI -1.0 to 1.1), P = 0.90]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.3 kg (95%CI -1.0 to 0.4), P = 0.47]. Meta-analysis of angiotensin converting enzyme inhibitor/angiotensin receptor blocker trials showed no clinically important treatment effect for the SPPB [between-group difference -0.1 points (95%CI -0.4 to 0.2)]. CONCLUSIONS: Neither perindopril nor leucine improved physical performance or muscle mass in this trial; meta-analysis did not find evidence of efficacy of either ACE inhibitors or leucine as treatments to improve physical performance.


Asunto(s)
Leucina , Perindopril , Rendimiento Físico Funcional , Sarcopenia , Anciano , Femenino , Fuerza de la Mano/fisiología , Humanos , Leucina/uso terapéutico , Masculino , Metaanálisis como Asunto , Perindopril/uso terapéutico , Sarcopenia/tratamiento farmacológico , Sarcopenia/fisiopatología , Resultado del Tratamiento
14.
Biol Trace Elem Res ; 199(6): 2182-2190, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32767246

RESUMEN

The experiment was conducted to study the effect of supplementation of designer dietary antioxidant micronutrients on udder health, milk yield, and its quality in buffaloes under field conditions. Sixteen healthy multiparous advanced pregnant graded Murrah buffaloes (around the last 3 months of gestation), identical in body weights, parity, and feeding conditions, were selected for the study. Feed offered and residues left of an individual animal were measured and recorded for 7 consecutive days with the sampling of feeds being offered to buffaloes and analyzed for dry matter and trace minerals Zn, Cu, and Se. Carotene and vitamin E content of offered feed samples were calculated based on reported values. The calculation was made to determine the deficiency of above micronutrients, and an antioxidant micronutrient supplement was designed to take care of the deficient micronutrients and supplemented in half of the buffaloes (n = 8) considered to be a treatment, while remaining half (n = 8) is considered to be control, fed as per the existing practice of farmer without additional supplementation. This supplementation study was continued for 2 months during advanced pregnancy and thereafter for 3 months post-calving. Dry matter intake recorded weekly during the pre- and postpartum period of study remained comparable (P > 0.05) between two groups. Udder health monitored fortnightly by modified California mastitis test, milk pH and somatic cell count indicated improvement (P < 0.05) of strategic antioxidant micronutrients supplementation. Milk yield started showing improvement (P < 0.05) as early as the first week after starting lactation with throughout enhanced (P < 0.05) values of milk protein, fat percentage, and fat-corrected milk yield. It may be concluded that strategic antioxidant micronutrient supplementation (Zn, Cu, and vitamins A and E) in the ration of peri-parturient buffaloes not only improved the udder health by reducing the occurrence of mastitis but also increased the milk yield as well as fat and protein percentage of milk.


Asunto(s)
Búfalos , Glándulas Mamarias Animales , Alimentación Animal/análisis , Animales , Antioxidantes , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Lactancia , Micronutrientes , Embarazo
15.
J Exp Med ; 218(9)2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34269789

RESUMEN

Studying latent Mycobacterium tuberculosis (Mtb) infection has been limited by the lack of a suitable mouse model. We discovered that transient depletion of biotin protein ligase (BPL) and thioredoxin reductase (TrxB2) results in latent infections during which Mtb cannot be detected but that relapse in a subset of mice. The immune requirements for Mtb control during latency, and the frequency of relapse, were strikingly different depending on how latency was established. TrxB2 depletion resulted in a latent infection that required adaptive immunity for control and reactivated with high frequency, whereas latent infection after BPL depletion was independent of adaptive immunity and rarely reactivated. We identified immune signatures of T cells indicative of relapse and demonstrated that BCG vaccination failed to protect mice from TB relapse. These reproducible genetic latency models allow investigation of the host immunological determinants that control the latent state and offer opportunities to evaluate therapeutic strategies in settings that mimic aspects of latency and TB relapse in humans.


Asunto(s)
Inmunidad Adaptativa/fisiología , Tuberculosis Latente/inmunología , Mycobacterium tuberculosis/genética , Tuberculosis/inmunología , Animales , Antituberculosos/farmacología , Vacuna BCG/farmacología , Ligasas de Carbono-Nitrógeno/genética , Ligasas de Carbono-Nitrógeno/metabolismo , Dexametasona/farmacología , Modelos Animales de Enfermedad , Femenino , Regulación Bacteriana de la Expresión Génica , Tuberculosis Latente/etiología , Tuberculosis Latente/prevención & control , Pulmón/efectos de los fármacos , Pulmón/microbiología , Ratones Endogámicos C57BL , Mycobacterium tuberculosis/patogenicidad , Reproducibilidad de los Resultados , Tiorredoxina Reductasa 2/genética , Tiorredoxina Reductasa 2/metabolismo , Tuberculosis/microbiología , Tuberculosis/patología
16.
J Biol Chem ; 284(40): 27467-79, 2009 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-19638631

RESUMEN

Protein kinase G (PknG) in Mycobacterium tuberculosis has been shown to modulate phagosome-lysosome fusion. The protein has three distinct domains, an N-terminal Trx domain, a kinase domain, and a C-terminal TPR domain. The present study extensively analyzes the roles of these domains in regulating PknG kinase activity and function. We find that the kinase domain of PknG by itself is inactive, signifying the importance of the flanking domains. Although the deletion of the Trx domain severely impacts the activity of the protein, the C-terminal region also contributes significantly in regulating the activity of the kinase. Apart from this, PknG kinase activity is dependent on the presence of threonine 309 in the p + 1 loop of the activation segment. Mutating the conserved cysteine residues in the Trx motifs makes PknG refractory to changes in the redox environment. In vitro experiments identify threonine 63 as the major phosphorylation site of the protein. Importantly, we find that this is the only site in the protein that is phosphorylated in vivo. Macrophage infection studies reveal that the first 73 residues, the Trx motifs, and the threonine 63 residue are independently essential for modulating PknG-mediated survival of mycobacteria in its host. We have extended these studies to investigate the role of PknG and PknG mutants in the pathogenesis of mycobacteria in mice. Our results reinforce the findings from the macrophage infection experiments, and for the first time demonstrate that the expression of PknG in non-pathogenic mycobacteria allows the continued existence of these bacteria in host tissues.


Asunto(s)
Proteínas Quinasas Dependientes de GMP Cíclico/química , Proteínas Quinasas Dependientes de GMP Cíclico/metabolismo , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/fisiología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Sitios de Unión , Proteínas Quinasas Dependientes de GMP Cíclico/genética , Regulación Bacteriana de la Expresión Génica , Lisosomas/metabolismo , Macrófagos/microbiología , Ratones , Datos de Secuencia Molecular , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium smegmatis/enzimología , Mycobacterium smegmatis/genética , Oxidación-Reducción , Fosforilación , Estructura Terciaria de Proteína , Eliminación de Secuencia
17.
Future Healthc J ; 7(2): 143-148, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32550282

RESUMEN

Hospital mortality rates have frequently been improved by identifying diagnostic groups with high mortality and targeting interventions to those specific groups. We found that high residual inpatient mortality persisted after targeted measures had achieved an initial reduction, and that the causes were spread across a wide range of diagnostic groups. Further interventions were put in place consisting of a structured electronic mortality form and systematised mortality scrutiny and reporting (primary intervention) accompanied by a number of quality improvement interventions arising from the mortality analysis (secondary interventions). We found that those interventions were associated with progressive improvements in mortality rates and average lengths of inpatient stay over the 5-year study period. Winter quarter mortality improvements reached a high level of statistical significance but could not be attributed to changes in any particular diagnostic groups. We conclude that progress with mortality improvements is probably best achieved by applying both code-targeted and general interventions simultaneously.

18.
Am J Hematol ; 84(11): 733-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19806665

RESUMEN

The current salvage therapies for relapsed/refractory acute myeloid leukemia (AML) are unsatisfactory. Over the past 7 years, we have used two salvage regimens: fludarabine, cytarabine, and idarubicin with (FLAG-IM) or without gemtuzumab ozogamicin (GO) (9 mg/m(2) on Day 8) (FLAG-I) in relapsed/refractory AML. Three-quarters of patients also received concurrent G-CSF. Seventy-one patients were treated, 23 with FLAG-I and 48 with FLAG-IM. The median duration of follow-up was 30.6 months. The treatment groups were well balanced with median ages of 48 years (range 18-70) and 47 years (range 20-68), unfavorable cytogenetics in 57% and 35%, prior allogeneic stem cell transplant in 43% and 42%, and CR1 duration <1 year in 60% and 67%, respectively, for FLAG-I and FLAG-IM. The complete remission (CR) rate in the FLAG-I group was 39% with an additional 13% achieving a CRp [overall response rate (ORR) 52%]; the CR rate in the FLAG-IM group was 29% with an additional 27% achieving a CRp (ORR 56%). The median duration of response (DOR; 16.8 vs. 8.3 months), event-free survival (EFS; 7.4 vs. 4.1 months), and overall survival (OS; 8.8 vs. 5.0 months) trended to favor FLAG-I over FLAG-IM. The patients who received G-CSF concurrent with chemotherapy had superior overall response rate (ORR; 62% vs. 29%, P = 0.026), median EFS (6.2 vs. 3.4 months, P = 0.010), and OS (8.8 vs. 3.9 months, P = 0.004) when compared with those who sequentially received G-CSF and chemotherapy, regardless of chemotherapy regimen. The addition of GO, at this dose and schedule, to FLAG-I failed to improve the outcomes in patients with relapsed/refractory AML. The patients who received G-CSF concurrently with chemotherapy had improved outcomes. Am. J. Hematol., 2009. (c) 2009 Wiley-Liss, Inc.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Terapia Recuperativa/métodos , Adolescente , Adulto , Anciano , Aminoglicósidos/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Citarabina/administración & dosificación , Evaluación de Medicamentos , Femenino , Gemtuzumab , Humanos , Idarrubicina/administración & dosificación , Masculino , Persona de Mediana Edad , Inducción de Remisión , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Vidarabina/administración & dosificación , Vidarabina/análogos & derivados , Adulto Joven
19.
Nat Commun ; 10(1): 4970, 2019 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-31672993

RESUMEN

The viability of Mycobacterium tuberculosis (Mtb) depends on energy generated by its respiratory chain. Cytochrome bc1-aa3 oxidase and type-2 NADH dehydrogenase (NDH-2) are respiratory chain components predicted to be essential, and are currently targeted for drug development. Here we demonstrate that an Mtb cytochrome bc1-aa3 oxidase deletion mutant is viable and only partially attenuated in mice. Moreover, treatment of Mtb-infected marmosets with a cytochrome bc1-aa3 oxidase inhibitor controls disease progression and reduces lesion-associated inflammation, but most lesions become cavitary. Deletion of both NDH-2 encoding genes (Δndh-2 mutant) reveals that the essentiality of NDH-2 as shown in standard growth media is due to the presence of fatty acids. The Δndh-2 mutant is only mildly attenuated in mice and not differently susceptible to clofazimine, a drug in clinical use proposed to engage NDH-2. These results demonstrate the intrinsic plasticity of Mtb's respiratory chain, and highlight the challenges associated with targeting the pathogen's respiratory enzymes for tuberculosis drug development.


Asunto(s)
Antituberculosos/uso terapéutico , Desarrollo de Medicamentos , Complejo III de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/genética , Mycobacterium tuberculosis/genética , NADH Deshidrogenasa/genética , Tuberculosis/tratamiento farmacológico , Adaptación Fisiológica/genética , Animales , Callithrix , Transporte de Electrón , Complejo III de Transporte de Electrones/antagonistas & inhibidores , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Técnicas de Silenciamiento del Gen , Imidazoles/farmacología , Técnicas In Vitro , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/metabolismo , NADH Deshidrogenasa/antagonistas & inhibidores , Piperidinas/farmacología , Piridinas/farmacología , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/patología
20.
Age Ageing ; 37(5): 600-1, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18515294

RESUMEN

Alien limb syndrome (ALS) is a very rare condition where the affected persons are not able to recognise the affected limb as their own, and regard it as being foreign or alien to them. We present a patient with ALS secondary to corticobasal degeneration, which is a rare neurodegenerative parkinsonian disorder. We discuss the clinical features, neuropathology and management of corticobasal degeneration.


Asunto(s)
Ganglios Basales/patología , Corteza Cerebral/patología , Trastornos del Movimiento/etiología , Degeneración Nerviosa , Trastornos Parkinsonianos/diagnóstico , Extremidad Superior/inervación , Anciano de 80 o más Años , Ganglios Basales/fisiopatología , Corteza Cerebral/fisiopatología , Resultado Fatal , Humanos , Masculino , Trastornos del Movimiento/patología , Trastornos del Movimiento/fisiopatología , Trastornos Parkinsonianos/complicaciones , Trastornos Parkinsonianos/fisiopatología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA