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1.
Nature ; 627(8005): 759-762, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38538936

RESUMEN

The early evolution of a supernova (SN) can reveal information about the environment and the progenitor star. When a star explodes in vacuum, the first photons to escape from its surface appear as a brief, hours-long shock-breakout flare1,2, followed by a cooling phase of emission. However, for stars exploding within a distribution of dense, optically thick circumstellar material (CSM), the first photons escape from the material beyond the stellar edge and the duration of the initial flare can extend to several days, during which the escaping emission indicates photospheric heating3. Early serendipitous observations2,4 that lacked ultraviolet (UV) data were unable to determine whether the early emission is heating or cooling and hence the nature of the early explosion event. Here we report UV spectra of the nearby SN 2023ixf in the galaxy Messier 101 (M101). Using the UV data as well as a comprehensive set of further multiwavelength observations, we temporally resolve the emergence of the explosion shock from a thick medium heated by the SN emission. We derive a reliable bolometric light curve that indicates that the shock breaks out from a dense layer with a radius substantially larger than typical supergiants.

2.
Br J Cancer ; 130(8): 1261-1268, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38383704

RESUMEN

BACKGROUND: The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population. METHODS: In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020). RESULTS: Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%. CONCLUSIONS: This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.


Asunto(s)
Cesárea , Neoplasias , Embarazo , Humanos , Femenino , Estudios Retrospectivos , Neoplasias/diagnóstico , Neoplasias/epidemiología , Neoplasias/terapia , Reino Unido/epidemiología , Nacimiento Vivo
4.
NPJ Digit Med ; 6(1): 65, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-37046040

RESUMEN

Inattention can negatively impact several aspects of a child's life, including at home and school. Cognitive and physical interventions are two promising non-pharmaceutical approaches used to enhance attention abilities, with combined approaches often being marketed to teachers, therapists, and parents typically without research validation. Here, we assessed the feasibility of incorporating an integrated, cognitive-physical, closed-loop video game (body-brain trainer or 'BBT') as an after-school program, and also evaluated if there were attention benefits following its use. Twenty-two children (7-12 years of age) with a range of attention abilities were recruited to participate in this proof of concept, single-arm, longitudinal study (24 sessions over 8 weeks, ~30 min/day). We interrogated attention abilities through a parent survey of their child's behaviors, in addition to objective performance-based and neural measures of attention. Here we observed 95% compliance as well as, significant improvements on the parent-based reports of inattention and on cognitive tests and neural measures of attention that were comparable in scale to previous work. Exploratory measures of other cognitive control abilities and physical fitness also showed similar improvement, with exploratory evaluation of retained benefits on the primary attention-related outcomes being present 1-year later. Lastly, there was no correlation between the baseline parent-rated inattention score and the improvement on the primary task-based measures of attention, suggesting that intervention-based benefits were not solely attained by those who stood the most to gain. These pilot findings warrant future research to replicate and extend these findings.

6.
Eur Heart J Case Rep ; 6(6): ytac205, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35668845

RESUMEN

Background: Intrapericardial diaphragmatic hernias are a rare form of diaphragmatic hernia. The presentation is usually acute due to trauma or from iatrogenic causes. In some instances however, these patients can present years later. We describe an unusual case of transient constrictive pericarditis associated with herniation of omentum through a diaphgragmatic hernia extending into the pericardial space, which infarcted following recent bariatric surgery. A multi-disciplinary approach was required with surgical correction of the diaphragmatic defect and removal of omentum from the pericardial space. Case summary: A 38-year-old gentleman with a history of a remote abdominal stab wound and recent laparoscopic gastric sleeve procedure presented with sharp central chest pain radiating to the shoulder. Chest imaging [echocardiography, computed tomography (CT), and cardiac magnetic resonance imaging (MRI)] revealed the presence of an intrapericardial diaphragmatic hernia and herniation of devascularized omentum into the pericardial space. Surgery was undertaken to remove the pericardial omentum. Echocardiography and cardiac MRI revealed changes of pericardial constriction which resolved with anti-inflammatories. Discussion: A multi-disciplinary approach was required in this case with surgical correction of the diaphragmatic defect and removal of omentum from the pericardial space. Multi-modal imaging proved essential in the diagnosis of this rare condition, aiding in timely diagnosis, ongoing management decisions, and for assessing therapeutic response.

8.
ESMO Open ; 6(1): 100005, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33399072

RESUMEN

BACKGROUND: Cancer patients are at increased risk of death from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Cancer and its treatment affect many haematological and biochemical parameters, therefore we analysed these prior to and during coronavirus disease 2019 (COVID-19) and correlated them with outcome. PATIENTS AND METHODS: Consecutive patients with cancer testing positive for SARS-CoV-2 in centres throughout the United Kingdom were identified and entered into a database following local governance approval. Clinical and longitudinal laboratory data were extracted from patient records. Data were analysed using Mann-Whitney U test, Fisher's exact test, Wilcoxon signed rank test, logistic regression, or linear regression for outcomes. Hierarchical clustering of heatmaps was performed using Ward's method. RESULTS: In total, 302 patients were included in three cohorts: Manchester (n = 67), Liverpool (n = 62), and UK (n = 173). In the entire cohort (N = 302), median age was 69 (range 19-93 years), including 163 males and 139 females; of these, 216 were diagnosed with a solid tumour and 86 with a haematological cancer. Preinfection lymphopaenia, neutropaenia and lactate dehydrogenase (LDH) were not associated with oxygen requirement (O2) or death. Lymphocyte count (P < 0.001), platelet count (P = 0.03), LDH (P < 0.0001) and albumin (P < 0.0001) significantly changed from preinfection to during infection. High rather than low neutrophils at day 0 (P = 0.007), higher maximal neutrophils during COVID-19 (P = 0.026) and higher neutrophil-to-lymphocyte ratio (NLR; P = 0.01) were associated with death. In multivariable analysis, age (P = 0.002), haematological cancer (P = 0.034), C-reactive protein (P = 0.004), NLR (P = 0.036) and albumin (P = 0.02) at day 0 were significant predictors of death. In the Manchester/Liverpool cohort 30 patients have restarted therapy following COVID-19, with no additional complications requiring readmission. CONCLUSION: Preinfection biochemical/haematological parameters were not associated with worse outcome in cancer patients. Restarting treatment following COVID-19 was not associated with additional complications. Neutropaenia due to cancer/treatment is not associated with COVID-19 mortality. Cancer therapy, particularly in patients with solid tumours, need not be delayed or omitted due to concerns that treatment itself increases COVID-19 severity.


Asunto(s)
COVID-19/prevención & control , Neoplasias/terapia , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , SARS-CoV-2/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Proteína C-Reactiva/análisis , COVID-19/virología , Femenino , Humanos , L-Lactato Deshidrogenasa/metabolismo , Modelos Logísticos , Estudios Longitudinales , Recuento de Linfocitos , Linfocitos/metabolismo , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Neoplasias/metabolismo , Neutrófilos/metabolismo , Evaluación de Resultado en la Atención de Salud/métodos , Recuento de Plaquetas , SARS-CoV-2/fisiología , Reino Unido , Adulto Joven
10.
Am J Infect Control ; 48(12): 1497-1500, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32562714

RESUMEN

The use of a subcutaneous engineered securement device (SESD) for peripherally inserted central catheters (PICC) in an acute care setting was found to have a direct impact on central line associated bloodstream infection (CLABSI) rates compared to traditional adhesive engineered securement devices (AESD). OBJECTIVE: While the literature suggests the use of SESDs has had successful results for device securement, it is unknown to what extent they may impact CLABSI rates. Securement and stabilization performance among devices may be a direct risk factor for CLABSIs. METHODS: A retrospective quality review of 7,776 cases was conducted at a large academic medical center. The primary researcher implemented a quantitative design which was analyzed with demographics statistics and relative risk ratio. RESULTS: There was a 288% (n = 47) increase in relative risk of CLABSI found in the AESD group compared to the SESD group. The results imply the use of SESDs may improve nursing practice and patient outcomes lowering CLABSI rates in patients with PICCs by a reduction of risks associated with securement design differences.


Asunto(s)
Infecciones Relacionadas con Catéteres , Cateterismo Venoso Central , Cateterismo Periférico , Catéteres Venosos Centrales , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/prevención & control , Cateterismo Venoso Central/efectos adversos , Cateterismo Periférico/efectos adversos , Catéteres Venosos Centrales/efectos adversos , Hospitales Universitarios , Humanos , Estudios Retrospectivos
11.
Can Commun Dis Rep ; 45(2-3): 54-62, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-31015819

RESUMEN

Increasing rates of gonococcal (GC) infection and antimicrobial resistant (AMR) GC, are a serious public health concern for Canada and around the world. Previously recommended treatments are ineffective against many of the gonorrhea strains circulating today. The current recommendation for combination therapy is now being threatened by globally emerging and increasingly resistant strains. It is important that coordinated efforts be made now to ensure these new global strains do not become established in Canada. Otherwise, we will be faced with the possibility of persistent GC infection which can lead to pelvic inflammatory disease, infertility and chronic pelvic pain in women; and epididymitis in men. The presence of GC can also increase the risk of HIV acquisition and transmission. There are a number of reasons why we are facing this public health threat. GC infection is often asymptomatic and it is highly transmissible. People may hesitate to seek testing (or to offer testing). Treatment is complex: recommendations vary by site of infection and risk of resistance. Sexual contact during travel is an important source of imported emerging resistant global strains. The new screening and diagnostic Nucleic Acid Amplification Test (NAAT) is excellent but has decreased the number of cultures being done and therefore our capacity to track AMR-GC. There are four key actions that clinicians and front-line public health professionals can take to stem the increase in rates of GC and drug resistant GC. First, normalize and increase GC screening based on risk factors and emphasize the need for safer sex practices. NAAT is useful for screening, but culture is still needed for extra-genital sites. Second, conduct pretravel counselling and include a travel history as part of the risk assessment. Third, use culture along with NAAT to establish the diagnosis and follow up for test-of-cure. Finally, refer to the most current Canadian Guidelines on Sexually Transmitted Infections or provincial/territorial recommendations on combination therapies for patients and their contacts as recommendations may have changed in response to evolving AMR-GC trends.

12.
J Neurophysiol ; 122(1): 132-150, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30995138

RESUMEN

We review recent progress in using numerical models to relate utricular hair bundle and otoconial membrane (OM) structure to the functional requirements imposed by natural behavior in turtles. The head movements section reviews the evolution of experimental attempts to understand vestibular system function with emphasis on turtles, including data showing that accelerations occurring during natural head movements achieve higher magnitudes and frequencies than previously assumed. The structure section reviews quantitative anatomical data documenting topographical variation in the structures underlying macromechanical and micromechanical responses of the turtle utricle to head movement: hair bundles, OM, and bundle-OM coupling. The macromechanics section reviews macromechanical models that incorporate realistic anatomical and mechanical parameters and reveal that the system is significantly underdamped, contrary to previous assumptions. The micromechanics: hair bundle motion and met currents section reviews work based on micromechanical models, which demonstrates that topographical variation in the structure of hair bundles and OM, and their mode of coupling, result in regional specializations for signaling of low frequency (or static) head position and high frequency head accelerations. We conclude that computational models based on empirical data are especially promising for investigating mechanotransduction in this challenging sensorimotor system.


Asunto(s)
Mecanotransducción Celular , Modelos Neurológicos , Sáculo y Utrículo/fisiología , Animales , Sáculo y Utrículo/citología
13.
J Water Health ; 16(6): 938-946, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30540268

RESUMEN

The versatility of denaturing gradient gel electrophoresis (DGGE) protocol provides enough grounds for its wide application over an array of microorganisms. This work was designed to evaluate DGGE for the detection and confirmation of mycobacteria and their association, if any, with waterborne pathogens. A total of 76 samples comprising raw untreated water, schmutzdecke, floccules and final treated water obtained from a common water source, and two water treatment works (WTW1 and WTW2), were analysed. Thirty-five species were identified from the overall samples, with 7% (5/76), 13% (10/76) and 26% (20/76) from the common raw water source, WTW1 and WTW2 respectively. The majority of the species were Cyanobacteria, with high dominance in the raw water entering WTW2. In the final treated water of WTW1 Eutreptiella braarudii was found, and that of WTW2 contained Anabaena nereformis, Anabaena torulosa and Podocarpus nerrifolius. Furthermore, one Mycobacterium species was found in the raw water of WTW1 aside from the detection of Mycobacterium avium ssp. paratuberculosis by the technique. No association between mycobacteria and the other species was observed. This implies DGGE may be employed to study the diversity of other akin mycobacterial species from various sources, and not as a direct means of elucidating microbial associations.


Asunto(s)
Cianobacterias , Mycobacterium , Purificación del Agua , Animales , Electroforesis en Gel de Gradiente Desnaturalizante
14.
J Microbiol Methods ; 150: 24-28, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29792942

RESUMEN

The recovery of Mycobacterium avium subspecies paratuberculosis (Map) from the environment can be a laborious process - owing to Map being fastidious, its low number, and also high numbers of other microbial populations in such settings. Protocols i.e. filtration, decontamination and modified elution were devised to recover Map from spiked water sediments. Three culture media: Herrold's Egg Yolk Media (HEYM), Middlebrook 7H10 (M-7H10) and Bactec 12B were then employed to grow the organism following its elution. In the sterile sediment samples the recovery of Map was significant between the time of exposure for each of HEYM and M-7H10, and insignificant between both media (P < 0.05). However, in the non-sterile sediment samples, the HEYM grew other background microflora including moulds at all the times of exposure whilst 4 h followed by M-7H10 culture yielded Map colonies without any background microflora. Using sterile samples only for the Bactec 12B, the recovery of Map decreased as time of exposure increased. Based on these findings, M-7H10 should be considered for the recovery of Map from the natural environment including water sediments where the recovery of diverse microbial species remains a challenge. SIGNIFICANCE OF THE STUDY: Map is a robust pathogen that abides in the environment. In water treatment operations, Map associates with floccules and other particulate matter including sediments. It is also a fastidious organism, and its detection and recovery from the water environment is a laborious process and can be misleading within the abundance of other mycobacterial species owing to their close resemblance in phylogenetic traits. In the absence of a reliable recovery method, Map continues to pose public health risks through biofilm in household water tanks, hence the need for the development of a reliable recovery protocol to monitor the presence of Map in water systems in order to curtail its public health risks.


Asunto(s)
Medios de Cultivo/química , Descontaminación/métodos , Sedimentos Geológicos/microbiología , Mycobacterium avium subsp. paratuberculosis/crecimiento & desarrollo , Microbiología del Agua , Biopelículas , Recuento de Colonia Microbiana , Filtración/métodos , Mycobacterium/clasificación , Mycobacterium/crecimiento & desarrollo , Mycobacterium avium subsp. paratuberculosis/clasificación , Mycobacterium avium subsp. paratuberculosis/aislamiento & purificación , Filogenia , Salud Pública , Temperatura , Factores de Tiempo , Agua , Purificación del Agua , Abastecimiento de Agua
15.
Anal Biochem ; 552: 75-80, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29158129

RESUMEN

Interest in the recently discovered phenomenon of mitochondrial transfer between mammalian cells has gained momentum since it was first described in cell culture systems more than a decade ago. Mitochondria-targeting fluorescent dyes have been repurposed and are now widely used in these studies and in acute disease models, sometimes without due consideration of their limitations, while vectors containing mitochondrially-imported fluorescent proteins have complemented the use of mitochondria-targeting dyes. Genetic approaches that use mitochondrial DNA polymorphisms have also been used in some in vitro studies and in tumor models and are particularly useful where mtDNA is damaged or deleted. These approaches can also be used to study the long-term consequences of mitochondrial transfer such as in bone marrow and organ transplantation and in tumour biology where inherent mitochondrial damage is often a key feature. As research on intercellular mitochondrial transfer moves from cell culture into animal models and human diseases it will be important to understand the limitations of the various techniques in order to apply appropriate methodologies to address physiological and pathophysiological conditions.


Asunto(s)
Mitocondrias/metabolismo , Polimorfismo Genético , Células A549 , Animales , Células Cultivadas , ADN Mitocondrial/genética , Colorantes Fluorescentes/metabolismo , Marcadores Genéticos , Humanos , Ratones Endogámicos C57BL , Microscopía Confocal , Microscopía Fluorescente , Modelos Animales
16.
Can Commun Dis Rep ; 44(7-8): 150-156, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-31011295

RESUMEN

BACKGROUNDS: Hospitalizations associated with hepatitis C virus (HCV) infection and liver disease increased on average by 6.0% per year from 2004 to 2010 in Canada and were projected (in 2010) to increase by another 4% by 2016. The first generation of direct-acting antivirals (DAAs) became available in 2012. In 2014, a second generation of effective and well-tolerated DAA therapy was authorized in Canada. The impact of DAA therapy on the HCV-associated disease burden in Canada has not been documented. OBJECTIVES: To assess the potential impact of DAA therapy on the disease burden by a) comparing the actual hospitalization rates associated with HCV infection and liver disease following the introduction of DAAs in Canada with the 2010 baseline projection and b) documenting the associated uptake of anti-HCV therapy. METHODS: The hospital records of inpatients diagnosed with chronic HCV and chronic liver disease were extracted from the Canadian Discharge Abstract Database (DAD) by fiscal year for 2004-2016. We compared the actual number of hospitalizations to the baseline projection by year and for selected 5-year birth cohorts (1925-1989). The monthly number of new prescriptions for anti-HCV regimens was extracted from the IQVIA CDH CompuScript database (formerly IMS Health), aggregated to annual levels by age group and compared with hospitalization trends. RESULTS: Compared to the baseline projection, there was a slight reduction in hospitalizations in 2014/15 and 2015/16. This slight reduction was followed by a more significant decline in 2016/17 (32% below expected; 95% confidence interval [CI]: 27%-37%). The largest declines were observed for patients born before 1960 (age 55 or older) at 40% below expected in 2016/17. The number of new anti-HCV prescriptions increased from 5,484 in fiscal year 2012/13 to a peak of 17,775 in 2015/2016. The number of new prescriptions corresponds to approximately 1.3 and five times the number of hospitalizations in 2012/13 and 2015/16, respectively. CONCLUSIONS: In Canada there has been a modest decrease in HCV and liver-related hospitalizations following a significant increase in uptake of second-generation DAAs in 2015. However, the burden is still high. Linked health administrative databases created to monitor the disease burden in the new treatment era should provide additional insight with the linkage of treatment history and disease stage to individual outcomes.

17.
BMC Psychiatry ; 17(1): 72, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28212630

RESUMEN

BACKGROUND: Increasing numbers of programs are addressing the specific needs of homeless people with schizophrenia in terms of access to housing, healthcare, basic human rights and other domains. Although quality of life scales are being used to evaluate such programs, few instruments have been validated for people with schizophrenia and none for people with schizophrenia who experience major social problems such as homelessness. The aim of the present study was to validate the French version of the S-QoL a self-administered, subjective quality of life questionnaire specific to schizophrenia for people with schizophrenia who are homeless. METHODS: In a two-step process, the S-QoL was first administered to two independent convenience samples of long-term homeless people with schizophrenia in Marseille, France. The objective of the first step was to analyse the psychometric properties of the S-QoL. The objective of the second step was to examine, through qualitative interviews with members of the population in question, the relevance and acceptability of the principle quality of life indicators used in the S-QoL instrument. RESULTS: Although the psychometric characteristics of the S-QoL were found to be globally satisfactory, from the point of view of the people being interviewed, acceptability was poor. Respondents frequently interrupted participation complaining that questionnaire items did not take into account the specific context of life on the streets. CONCLUSIONS: Less intrusive questions, more readily understandable vocabulary and greater relevance to subjects' living conditions are needed to improve the S-QoL questionnaire for this population. A modular questionnaire with context specific sections or specific quality of life instruments for socially excluded populations may well be the way forward.


Asunto(s)
Personas con Mala Vivienda/psicología , Calidad de Vida , Psicología del Esquizofrénico , Encuestas y Cuestionarios , Adulto , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Psicometría , Adulto Joven
18.
Can Commun Dis Rep ; 43(2): 33-37, 2017 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-29770062

RESUMEN

BACKGROUND: Cases of Neisseria gonorrhea are on the rise in Canada, which-if undetected or undertreated-can lead to morbidity and infertility. In addition, the number of antimicrobial resistant strains is also increasing creating the risk that N. gonorrhea may become untreatable. In 2013, the Public Health Agency of Canada (PHAC) released Canadian recommendations for the management and treatment of gonorrhea that identified the need for combination therapy to address and minimize antimicrobial resistance. However, the level of awareness and uptake of these guidelines is not well-known. OBJECTIVES: To assess primary care physicians' prescribing practices for the management and treatment of gonorrhea. METHODS: After validity testing, two online cross-sectional surveys were conducted with a convenience sample of Canadian physicians. Physicians answered true/false statements and open-ended questions relating to three clinical scenarios: 1) suspected anogenital infection drawing from a population of men who have sex with men (MSM); 2) suspected anogenital infection drawing from a non-MSM population; and, 3) suspected pharyngeal infection drawing from any population. Frequencies of responses were calculated for the statements. Open-ended responses were recoded into treatment categories and frequencies were calculated for each scenario. RESULTS: A total of 625 physicians completed the survey. Most physicians (60%-95%) accurately identified knowledge statements regarding pharmaceutical management, partner notification and public health reporting. For all clinical scenarios, 30%-35% of physicians did not provide any treatment information, approximately 30% indicated treating with cephalosporin monotherapy, 20%-25% indicated they would prescribe a cephalosporin and azithromycin and a minority of physicians identified other treatment options. When physicians were asked about the purpose of the second antibiotic, azithromycin, 49% indicated it was to provide presumptive treatment for gonorrhea and chlamydia. Forty-one percent indicated it was to provide presumptive treatment for chlamydia only. CONCLUSION: This convenience sample suggests that although knowledge of pharmaceutical management, partner notification, and public health reporting is high, the use of combination therapy to deter the development of antimicrobial resistant gonorrhea may not be widespread among primary care physicians. In light of both the growing incidence of N. gonorrhea and the rising rates of antimicrobial resistance in Canada, consideration on how to improve awareness and update of best prescribing practices in primary care may be indicated.

19.
Lab Anim ; 51(2): 181-190, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27118731

RESUMEN

Fetal growth restriction (FGR) is a common and potentially severe pregnancy complication. Currently there is no treatment available. The guinea pig is an attractive model of human pregnancy as placentation is morphologically very similar between the species. Nutrient restriction of the dam creates growth-restricted fetuses while leaving an intact uteroplacental circulation, vital for evaluating novel therapies for FGR. Growth-restricted fetuses were generated by feeding Dunkin Hartley guinea pig dams 70% of ad libitum intake from four weeks before and throughout pregnancy. The effect of maternal nutrient restriction (MNR) on dams and fetuses was carefully monitored, and ultrasound measurements of pups collected. There was no difference in maternal weight at conception, however by five weeks post conception MNR dams were significantly lighter ( P < 0.05). MNR resulted in significantly smaller pup size from 0.6-0.66 gestation. Ultrasound is a powerful non-invasive tool for assessing the effect of therapeutic interventions on fetal growth, allowing longitudinal measurement of fetuses. This model and method yield data applicable to the human condition without the need for animal sacrifice and will be useful in the translation of therapies for FGR into the clinic.


Asunto(s)
Restricción Calórica , Fertilización , Desarrollo Fetal , Retardo del Crecimiento Fetal/diagnóstico por imagen , Cobayas/crecimiento & desarrollo , Tamaño de la Camada , Pérdida de Peso , Animales , Modelos Animales de Enfermedad , Femenino , Ultrasonografía Prenatal
20.
J Appl Microbiol ; 121(5): 1457-1468, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27563832

RESUMEN

AIMS: Persistence of Mycobacterium bovis was investigated in UK raw milk cheeses. METHODS AND RESULTS: Replicating traditional cheese production methods under stringent CL3 containment conditions, Cheddar and Caerphilly cheeses were produced with Myco. bovis inoculated raw milk. High-inoculum investigations used three Myco. bovis genotypes; later low-inoculum investigations used only Myco. bovis AF2122/97. High-inoculum Cheddar (n = 9) and Caerphilly (n = 9) were matured for a minimum of 12 and 4 months respectively; maturation of low-inoculum Cheddar (n = 3) and Caerphilly (n = 3) was up to 11 weeks. Survival of Myco. bovis was monitored by enumeration at different points throughout cheese manufacture and ripening. D values were calculated as follows: 57 and 59 days in high-inoculum Cheddar and Caerphilly, respectively, and 41 and 24 days in low-inoculum Cheddar and Caerphilly respectively. CONCLUSIONS: Mycobacterium bovis is concentrated in cheese curd and a proportion lost with the whey. Reduction in viability during manufacturing is limited, while significant Myco. bovis inactivation occurs during maturation. Inactivation was improved, during Caerphilly ripening, when acid development was enhanced by increasing the proportion of starter culture. SIGNIFICANCE AND IMPACT OF THE STUDY: Mycobacterium bovis inactivation data obtained could be used to inform assessment of the risk posed to consumers by raw milk dairy products.


Asunto(s)
Queso/microbiología , Microbiología de Alimentos , Mycobacterium bovis/aislamiento & purificación , Animales , Industria de Alimentos , Cinética , Viabilidad Microbiana , Leche/microbiología
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