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1.
Ann Oncol ; 35(6): 523-536, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38408508

RESUMO

BACKGROUND: The incidence of early-onset colorectal cancer (EOCRC; diagnosed <50 years of age) is rising globally; however, the causes underlying this trend are largely unknown. CRC has strong genetic and environmental determinants, yet common genetic variants and causal modifiable risk factors underlying EOCRC are unknown. We conducted the first EOCRC-specific genome-wide association study (GWAS) and Mendelian randomization (MR) analyses to explore germline genetic and causal modifiable risk factors associated with EOCRC. PATIENTS AND METHODS: We conducted a GWAS meta-analysis of 6176 EOCRC cases and 65 829 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT), the Colon Cancer Family Registry (CCFR), and the UK Biobank. We then used the EOCRC GWAS to investigate 28 modifiable risk factors using two-sample MR. RESULTS: We found two novel risk loci for EOCRC at 1p34.1 and 4p15.33, which were not previously associated with CRC risk. We identified a deleterious coding variant (rs36053993, G396D) at polyposis-associated DNA repair gene MUTYH (odds ratio 1.80, 95% confidence interval 1.47-2.22) but show that most of the common genetic susceptibility was from noncoding signals enriched in epigenetic markers present in gastrointestinal tract cells. We identified new EOCRC-susceptibility genes, and in addition to pathways such as transforming growth factor (TGF) ß, suppressor of Mothers Against Decapentaplegic (SMAD), bone morphogenetic protein (BMP) and phosphatidylinositol kinase (PI3K) signaling, our study highlights a role for insulin signaling and immune/infection-related pathways in EOCRC. In our MR analyses, we found novel evidence of probable causal associations for higher levels of body size and metabolic factors-such as body fat percentage, waist circumference, waist-to-hip ratio, basal metabolic rate, and fasting insulin-higher alcohol drinking, and lower education attainment with increased EOCRC risk. CONCLUSIONS: Our novel findings indicate inherited susceptibility to EOCRC and suggest modifiable lifestyle and metabolic targets that could also be used to risk-stratify individuals for personalized screening strategies or other interventions.


Assuntos
Neoplasias Colorretais , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Adulto , Feminino , Humanos , Masculino , Idade de Início , Estudos de Casos e Controles , Neoplasias Colorretais/genética , Neoplasias Colorretais/epidemiologia , Polimorfismo de Nucleotídeo Único , Fatores de Risco
2.
Horm Behav ; 164: 105577, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38878493

RESUMO

Social stress is a negative emotional experience that can increase fear and anxiety. Dominance status can alter the way individuals react to and cope with stressful events. The underlying neurobiology of how social dominance produces stress resistance remains elusive, although experience-dependent changes in androgen receptor (AR) expression is thought to play an essential role. Using a Syrian hamster (Mesocricetus auratus) model, we investigated whether dominant individuals activate more AR-expressing neurons in the posterior dorsal and posterior ventral regions of the medial amygdala (MePD, MePV), and display less social anxiety-like behavior following social defeat stress compared to subordinate counterparts. We allowed male hamsters to form and maintain a dyadic dominance relationship for 12 days, exposed them to social defeat stress, and then tested their approach-avoidance behavior using a social avoidance test. During social defeat stress, dominant subjects showed a longer latency to submit and greater c-Fos expression in AR+ cells in the MePD/MePV compared to subordinates. We found that social defeat exposure reduced the amount of time animals spent interacting with a novel conspecific 24 h later, although there was no effect of dominance status. The amount of social vigilance shown by dominants during social avoidance testing was positively correlated with c-Fos expression in AR+ cells in the MePV. These findings indicate that dominant hamsters show greater neural activity in AR+ cells in the MePV during social defeat compared to their subordinate counterparts, and this pattern of neural activity correlates with their proactive coping response. Consistent with the central role of androgens in experience-dependent changes in aggression, activation of AR+ cells in the MePD/MePV contributes to experience-dependent changes in stress-related behavior.

3.
J Oncol Pharm Pract ; 30(1): 127-141, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37122190

RESUMO

PURPOSE: Oncology care continues to evolve at a rapid pace including provision of infusion-based care. There is currently a lack of robust metrics around oncology infusion centers and pharmacy practice. The workgroup completed a nationwide survey to learn about oncology-based infusion pharmacy services offered. The objective was to highlight consistent, measureable oncology-based infusion pharmacy metrics that will provide a foundation to describe overall productivity including emphasis on high patient-safety standards. METHODS: A nationwide survey was developed via a workgroup within the Vizient Pharmacy Cancer Care Group beginning in April 2019 and conducted electronically via the Vizient Pharmacy Network from September to November 2020. The survey was designed to capture a number of key metrics related to oncology-based infusion pharmacy services. RESULTS: Forty-one sites responded to the survey. Responses highlighted hours of operation (median = 11.5), number of infusion chairs (median = 45). Staffing metrics included 7.1 pharmacist full-time equivalent (FTE) and 7.6 technician FTE per week. 80.5% of sites had cleanrooms and 95.1% reported both hazardous and nonhazardous compounding hoods. 68.3% of sites reported using intravenous (IV) technology, 50.0% measured turnaround time, and 31.4% prepared treatment medications in advance. CONCLUSION: There was variability among oncology infusion pharmacy practices in regard to survey responses among sites. The survey results highlight the need for standardization of established productivity metrics across oncology infusion pharmacies in order to improve efficiency and contain costs in the changing oncology landscape. The survey provides insight into oncology infusion pharmacy practices nationwide and provides information for pharmacy leaders to help guide their practices.


Assuntos
Assistência Farmacêutica , Farmácias , Farmácia , Humanos , Oncologia , Farmacêuticos , Inquéritos e Questionários , Bombas de Infusão
4.
Anaesthesia ; 76(10): 1377-1391, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33984872

RESUMO

The need to evacuate an ICU or operating theatre complex during a fire or other emergency is a rare event but one potentially fraught with difficulty: Not only is there a risk that patients may come to harm but also that staff may be injured and unable to work. Designing newly-built or refurbished ICUs and operating theatre suites is an opportunity to incorporate mandatory fire safety features and improve the management and outcomes of such emergencies: These include well-marked manual fire call points and oxygen shut off valves (area valve service units); the ability to isolate individual zones; multiple clear exit routes; small bays or side rooms; preference for ground floor ICU location and interconnecting routes with operating theatres; separate clinical and non-clinical areas. ICUs and operating theatre suites should have a bespoke emergency evacuation plan and route map that is readily available. Staff should receive practical fire and evacuation training in their clinical area of work on induction and annually as part of mandatory training, including 'walk-through practice' or simulation training and location of manual fire call points and fire extinguishers, evacuation routes and location and operation of area valve service units. The staff member in charge of each shift should be able to select and operate fire extinguishers and lead an evacuation. Following an emergency evacuation, a network-wide response should be activated, including retrieval and transport of patients to other ICUs if needed. A full investigation should take place and ongoing support and follow-up of staff provided.


Assuntos
Desastres , Incêndios , Unidades de Terapia Intensiva , Salas Cirúrgicas , Gestão da Segurança/métodos , Emergências , Inundações , Humanos
5.
Proc Natl Acad Sci U S A ; 115(9): E2068-E2076, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29440406

RESUMO

Chimeric antigen receptor T (CAR-T) cells are effective serial killers with a faster off-rate from dying tumor cells than CAR-T cells binding target cells through their T cell receptor (TCR). Here we explored the functional consequences of CAR-mediated signaling using a dual-specific CAR-T cell, where the same cell was triggered via TCR (tcrCTL) or CAR (carCTL). The carCTL immune synapse lacked distinct LFA-1 adhesion rings and was less reliant on LFA to form stable conjugates with target cells. carCTL receptors associated with the synapse were found to be disrupted and formed a convoluted multifocal pattern of Lck microclusters. Both proximal and distal receptor signaling pathways were induced more rapidly and subsequently decreased more rapidly in carCTL than in tcrCTL. The functional consequence of this rapid signaling in carCTL cells included faster lytic granule recruitment to the immune synapse, correlating with faster detachment of the CTL from the target cell. This study provides a mechanism for how CAR-T cells can debulk large tumor burden quickly and may contribute to further refinement of CAR design for enhancing the quality of signaling and programming of the T cell.


Assuntos
Sinapses Imunológicas/imunologia , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Complexo CD3 , Adesão Celular , Morte Celular , Linhagem Celular Tumoral , Biologia Computacional , Citocinas/metabolismo , Dineínas/química , Ligantes , Ativação Linfocitária , Antígeno-1 Associado à Função Linfocitária/imunologia , Camundongos , Microtúbulos/metabolismo , Transdução de Sinais
6.
Psychiatr Psychol Law ; 28(2): 274-285, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712096

RESUMO

In March 2019, a mass shooting at two Christchurch mosques, livestreamed to Facebook, resulted in the deaths of 51 people. Psychologically, this served as a focusing event with high threat salience, shocking a country unused to gun violence despite its comparatively lax firearm legislation. The unprecedented reluctance by the New Zealand media to feature the shooter as a protagonist or even publish his name, concentrating instead on victims and societal issues, helped promote a sense of collective responsibility for change. This was strongly modeled by political leaders. Within weeks, new gun control laws were introduced with bipartisan support. We present this as a national case study, considering psychological and societal enablers for legislative reform in response to extreme gun violence. The shooting also raised the intractable problem of the internet allowing terrorists to promulgate violent content and extremist ideology with regulation in this area harder to achieve than gun control.

7.
Br J Dermatol ; 182(5): 1262-1268, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31378928

RESUMO

BACKGROUND: Melanoma risk prediction models could be useful for matching preventive interventions to patients' risk. OBJECTIVES: To develop and validate a model for incident first-primary cutaneous melanoma using clinically assessed risk factors. METHODS: We used unconditional logistic regression with backward selection from the Australian Melanoma Family Study (461 cases and 329 controls) in which age, sex and city of recruitment were kept in each step, and we externally validated it using the Leeds Melanoma Case-Control Study (960 cases and 513 controls). Candidate predictors included clinically assessed whole-body naevi and solar lentigines, and self-assessed pigmentation phenotype, sun exposure, family history and history of keratinocyte cancer. We evaluated the predictive strength and discrimination of the model risk factors using odds per age- and sex-adjusted SD (OPERA) and the area under curve (AUC), and calibration using the Hosmer-Lemeshow test. RESULTS: The final model included the number of naevi ≥ 2 mm in diameter on the whole body, solar lentigines on the upper back (a six-level scale), hair colour at age 18 years and personal history of keratinocyte cancer. Naevi was the strongest risk factor; the OPERA was 3·51 [95% confidence interval (CI) 2·71-4·54] in the Australian study and 2·56 (95% CI 2·23-2·95) in the Leeds study. The AUC was 0·79 (95% CI 0·76-0·83) in the Australian study and 0·73 (95% CI 0·70-0·75) in the Leeds study. The Hosmer-Lemeshow test P-value was 0·30 in the Australian study and < 0·001 in the Leeds study. CONCLUSIONS: This model had good discrimination and could be used by clinicians to stratify patients by melanoma risk for the targeting of preventive interventions. What's already known about this topic? Melanoma risk prediction models may be useful in prevention by tailoring interventions to personalized risk levels. For reasons of feasibility, time and cost many melanoma prediction models use self-assessed risk factors. However, individuals tend to underestimate their naevus numbers. What does this study add? We present a melanoma risk prediction model, which includes clinically-assessed whole-body naevi and solar lentigines, and self-assessed risk factors including pigmentation phenotype and history of keratinocyte cancer. This model performs well on discrimination, the model's ability to distinguish between individuals with and without melanoma, and may assist clinicians to stratify patients by melanoma risk for targeted preventive interventions.


Assuntos
Lentigo , Melanoma , Neoplasias Cutâneas , Adolescente , Austrália/epidemiologia , Estudos de Casos e Controles , Humanos , Lentigo/epidemiologia , Melanoma/diagnóstico , Melanoma/epidemiologia , Melanoma/etiologia , Fatores de Risco , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia
8.
Ann Oncol ; 30(4): 510-519, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30721924

RESUMO

Despite significant progress in our understanding of the etiology, biology and genetics of colorectal cancer, as well as important clinical advances, it remains the third most frequently diagnosed cancer worldwide and is the second leading cause of cancer death. Based on demographic projections, the global burden of colorectal cancer would be expected to rise by 72% from 1.8 million new cases in 2018 to over 3 million in 2040 with substantial increases anticipated in low- and middle-income countries. In this meeting report, we summarize the content of a joint workshop led by the National Cancer Institute and the International Agency for Research on Cancer, which was held to summarize the important achievements that have been made in our understanding of colorectal cancer etiology, genetics, early detection and treatment and to identify key research questions that remain to be addressed.


Assuntos
Neoplasias Colorretais , Congressos como Assunto , Carga Global da Doença/tendências , Cooperação Internacional , Carga Global da Doença/estatística & dados numéricos , Humanos , Oncologia/organização & administração , Oncologia/estatística & dados numéricos , Oncologia/tendências , National Cancer Institute (U.S.)/estatística & dados numéricos , Estados Unidos
9.
BMC Neurol ; 19(1): 20, 2019 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-30738426

RESUMO

BACKGROUND: Currently there are no disease-modifying treatments for Parkinson's disease dementia (PDD), a condition linked to aggregation of the protein α-synuclein in subcortical and cortical brain areas. One of the leading genetic risk factors for Parkinson's disease is being a carrier in the gene for ß-Glucocerebrosidase (GCase; gene name GBA1). Studies in cell culture and animal models have shown that raising the levels of GCase can decrease levels of α-synuclein. Ambroxol is a pharmacological chaperone for GCase and is able to raise the levels of GCase and could therefore be a disease-modifying treatment for PDD. The aims of this trial are to determine if Ambroxol is safe and well-tolerated by individuals with PDD and if Ambroxol affects cognitive, biochemical, and neuroimaging measures. METHODS: This is a phase II, single-centre, double-blind, randomized placebo-controlled trial involving 75 individuals with mild to moderate PDD. Participants will be randomized into Ambroxol high-dose (1050 mg/day), low-dose (525 mg/day), or placebo treatment arms. Assessments will be undertaken at baseline, 6-months, and 12-months follow up times. Primary outcome measures will be the Alzheimer's disease Assessment Scale-cognitive subscale (ADAS-Cog) and the ADCS Clinician's Global Impression of Change (CGIC). Secondary measures will include the Parkinson's disease Cognitive Rating Scale, Clinical Dementia Rating, Trail Making Test, Stroop Test, Unified Parkinson's disease Rating Scale, Purdue Pegboard, Timed Up and Go, and gait kinematics. Markers of neurodegeneration will include MRI and CSF measures. Pharmacokinetics and pharmacodynamics of Ambroxol will be examined through plasma levels during dose titration phase and evaluation of GCase activity in lymphocytes. DISCUSSION: If found effective and safe, Ambroxol will be one of the first disease-modifying treatments for PDD. TRIAL REGISTRATION: ClinicalTrials.gov NCT02914366, 26 Sep 2016/retrospectively registered.


Assuntos
Ambroxol/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Projetos de Pesquisa , Idoso , Encéfalo/efeitos dos fármacos , Demência/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/psicologia
10.
J Eur Acad Dermatol Venereol ; 33(10): 1874-1885, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31087403

RESUMO

BACKGROUND: People at high risk of developing melanoma are usually identified by pigmentary and naevus phenotypes. OBJECTIVE: We examined whether associations of these phenotypes with melanoma risk differed by ambient sun exposure or participant characteristics in two population-based, case-control studies with comparable ancestry but different ambient sun exposure. METHODS: Data were analysed from 616 cases and 496 controls from the Australian Melanoma Family Study and 2012 cases and 504 controls from the Leeds (UK) case-control study. Questionnaire, interview and dermatological skin examination data were collected using the same measurement protocols. Relative risks were estimated as odds ratios using unconditional logistic regression, adjusted for potential confounders. RESULTS: Hair and skin colour were the strongest pigmentary phenotype risk factors. All associations of pigmentary phenotype with melanoma risk were similar across countries. The median number of clinically assessed naevi was approximately three times higher in Australia than Leeds, but the relative risks for melanoma associated with each additional common or dysplastic naevus were higher for Leeds than Australia, especially for naevi on the upper and lower limbs. Higher naevus counts on the head and neck were associated with a stronger relative risk for melanoma for women than men. The two countries had similar relative risks for melanoma based on self-reported naevus density categories, but personal perceptions of naevus number differed by country. There was no consistent evidence of interactions between phenotypes on risk. CONCLUSIONS: Classifying people at high risk of melanoma based on their number of naevi should ideally take into account their country of residence, type of counts (clinical or self-reported), body site on which the naevus counts are measured and sex. The presence of naevi may be a stronger indicator of a genetic predisposition in the UK than in Australia based on less opportunity for sun exposure to influence naevus development.


Assuntos
Exposição Ambiental , Melanoma/etnologia , Nevo Pigmentado/etnologia , Neoplasias Cutâneas/etnologia , Pigmentação da Pele , Luz Solar , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Estudos de Casos e Controles , Extremidades , Feminino , Cor de Cabelo , Humanos , Masculino , Pessoa de Meia-Idade , Nevo Pigmentado/patologia , Fenótipo , Medição de Risco , Fatores de Risco , Fatores Sexuais , Neoplasias Cutâneas/patologia , Carga Tumoral , Reino Unido/epidemiologia , População Branca , Adulto Jovem
11.
Br J Surg ; 105(4): 315-327, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29488648

RESUMO

BACKGROUND: Recent advances in endovascular technology have enabled minimally invasive repair of the aortic arch, with specifically designed stent-grafts. This article reviews hybrid and total endovascular repair in the management of aortic arch pathology. METHODS: Studies relating to aortic arch management were identified using MEDLINE and Embase, focusing on endovascular repair. RESULTS: Hybrid arch repair is associated with an early mortality rate of some 12 per cent, and carries significant risk of stroke (up to 15 per cent), paraplegia (up to 6 per cent), retrograde dissection (up to 6·5 per cent) and proximal endoleak (6 per cent). Despite patients being of overall higher perioperative risk, hybrid repair has morbidity and early mortality rates comparable to those of open arch replacement. However, rates of freedom from aortic rupture or reintervention are significantly lower in the longer term, owing to the incidence of endoleak. Total endovascular arch repair may be achieved by the use of parallel stents or in situ fenestration in the emergency setting, or use of custom-made devices (scalloped, fenestrated or branched stent-grafts) in the elective setting. Reports of these relatively novel technologies suggest acceptable short-term outcomes, but long-term data are still awaited. CONCLUSION: Repair of aortic arch pathology presents a formidable challenge for endovascular technology. Open aortic arch repair remains the standard in younger, fitter patients, but endovascular technology and experience continue to evolve with encouraging early outcomes and expanding indications.


Assuntos
Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/métodos , Doenças da Aorta/mortalidade , Humanos , Resultado do Tratamento
12.
Parasitology ; 145(8): 1051-1058, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29239290

RESUMO

A time-course study was conducted to resolve discrepancies in the literature and better define aspects of the Eimeria maxima life cycle such, as sites of development and both morphology and number of asexual stages. Broiler chickens were inoculated orally with five million E. maxima oocysts (APU1), and were necropsied at regular intervals from 12 to 120 h p.i. Small intestine tissue sections and smears were examined for developmental stages. The jejunum contained the highest numbers of developmental stages. At 12 h p.i., sporozoites were observed inside a parasitophorous vacuole (PV) in the epithelial villi and the lamina propria. By 24 h, sporozoites enclosed by a PV were observed in enterocytes of the glands of Lieberkühn. At 48 h p.i., sporozoites, elongated immature and mature schizonts, were all seen in the glands with merozoites budding off from a residual body. By 60 h, second-generation, sausage-shaped schizonts containing up to 12 merozoites were observed around a residual body in the villar tip of invaded enterocytes. At 72 and 96 h, profuse schizogony associated with third- and fourth-generation schizonts was observed throughout the villus. At 120 h, another generation (fifth) of schizonts were seen in villar tips as well as in subepithelium where gamonts and oocysts were also present; a few gamonts were in epithelium. Our finding of maximum parasitization of E. maxima in jejunum is important because this region is critical for nutrient absorption and weight gain.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Doenças das Aves Domésticas/parasitologia , Animais , Eimeria/ultraestrutura , Enterócitos/parasitologia , Enterócitos/ultraestrutura , Intestino Delgado/citologia , Intestino Delgado/parasitologia , Merozoítos/fisiologia , Merozoítos/ultraestrutura , Mucosa/citologia , Mucosa/parasitologia , Oocistos , Esporozoítos/crescimento & desenvolvimento , Esporozoítos/ultraestrutura , Fatores de Tempo , Vacúolos/parasitologia , Vacúolos/ultraestrutura
13.
Vascular ; 25(3): 266-271, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27688294

RESUMO

Purpose The aim of this paper is to report our experience of type II endoleak treatment after endovascular aneurysm repair with intra-arterial injection of the embolizing liquid material, Onyx liquid embolic system. Methods From 2005 to 2012, we performed a retrospective review of 600 patients, who underwent endovascular repair of an abdominal aortic aneurysm. During this period, 18 patients were treated with Onyx for type II endoleaks. Principal findings The source of the endoleak was the internal iliac artery in seven cases, inferior mesenteric artery in seven cases and lumbar arteries in four cases. Immediate technical success was achieved in all patients and no endoleak from the treated vessel recurred. During a mean follow-up of 19 months, no major morbidity or mortality occurred, and one-year survival was 100%. Conclusions Treatment of type II endoleaks with Onyx is safe and effective over a significant time period.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Dimetil Sulfóxido/administração & dosagem , Embolização Terapêutica/métodos , Endoleak/terapia , Procedimentos Endovasculares/efeitos adversos , Artéria Ilíaca , Vértebras Lombares/irrigação sanguínea , Artéria Mesentérica Inferior , Polivinil/administração & dosagem , Tantálio/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Angiografia por Tomografia Computadorizada , Dimetil Sulfóxido/efeitos adversos , Combinação de Medicamentos , Embolização Terapêutica/efeitos adversos , Endoleak/diagnóstico por imagem , Endoleak/etiologia , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , Injeções Intra-Arteriais , Masculino , Artéria Mesentérica Inferior/diagnóstico por imagem , Polivinil/efeitos adversos , Estudos Retrospectivos , Tantálio/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
14.
Nature ; 468(7324): 673-6, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21085118

RESUMO

Antimatter was first predicted in 1931, by Dirac. Work with high-energy antiparticles is now commonplace, and anti-electrons are used regularly in the medical technique of positron emission tomography scanning. Antihydrogen, the bound state of an antiproton and a positron, has been produced at low energies at CERN (the European Organization for Nuclear Research) since 2002. Antihydrogen is of interest for use in a precision test of nature's fundamental symmetries. The charge conjugation/parity/time reversal (CPT) theorem, a crucial part of the foundation of the standard model of elementary particles and interactions, demands that hydrogen and antihydrogen have the same spectrum. Given the current experimental precision of measurements on the hydrogen atom (about two parts in 10(14) for the frequency of the 1s-to-2s transition), subjecting antihydrogen to rigorous spectroscopic examination would constitute a compelling, model-independent test of CPT. Antihydrogen could also be used to study the gravitational behaviour of antimatter. However, so far experiments have produced antihydrogen that is not confined, precluding detailed study of its structure. Here we demonstrate trapping of antihydrogen atoms. From the interaction of about 10(7) antiprotons and 7 × 10(8) positrons, we observed 38 annihilation events consistent with the controlled release of trapped antihydrogen from our magnetic trap; the measured background is 1.4 ± 1.4 events. This result opens the door to precision measurements on anti-atoms, which can soon be subjected to the same techniques as developed for hydrogen.

17.
Colorectal Dis ; 17(9): 787-93, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25754680

RESUMO

AIM: Infertility is a concern for young survivors of colorectal cancer (CRC), but this risk is not well quantified. Carriers of mismatch repair (MMR) mutations are a useful cohort for studying fertility after CRC as they commonly develop CRC when young, and unaffected family members provide demographically similar controls. The aim of this study was to determine the effect of CRC on fertility in a large cohort of MMR mutation carriers. METHOD: Mismatch repair mutation carriers identified from the Australasian Colorectal Cancer Family Registry were included. For each year of life within the fertile age range (15-49), the number of living individuals and the number of children born to them were determined. Individuals were grouped by whether or not they had had a diagnosis of CRC by that age. Age-specific and total fertility rates were calculated. RESULTS: We identified 1068 subjects (611 women and 457 men), of whom 467 were diagnosed with CRC. There were 1192 births during 18 674 person-years of follow-up to the women and 814 births during 14 013 person-years of follow-up to the men. The total fertility rate was decreased in women after a diagnosis of CRC compared with those who did not have CRC (1.3 vs 2.2; P = 0.0011), but age-specific fertility was only reduced in the 20-24-year age group. In men the total fertility rate was similar for both groups (2.0 vs 1.8; P = 0.27). CONCLUSION: Age-specific fertility was decreased in female CRC survivors with Lynch syndrome aged 20-24, but not in older women or in men.


Assuntos
Coeficiente de Natalidade , Neoplasias do Colo/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Retais/diagnóstico , Adolescente , Adulto , Fatores Etários , Austrália , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
18.
Exp Parasitol ; 150: 13-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25617757

RESUMO

Avian coccidiosis is a disease caused by the intestinal protozoa Eimeria. The site of invasion and lesions in the intestine is species-specific, for example E. acervulina affects the duodenum, E. maxima the jejunum, and E. tenella the ceca. Lesions in the intestinal mucosa cause reduced feed efficiency and body weight gain. The growth reduction may be due to changes in expression of digestive enzymes and nutrient transporters in the intestine. The objective of this study was to compare the expression of digestive enzymes, nutrient transporters and an antimicrobial peptide in broilers challenged with either E. acervulina, E. maxima or E. tenella. The genes examined included digestive enzymes (APN and SI), peptide and amino acid transporters (PepT1, ASCT1, b(0,+)AT/rBAT, B(0)AT, CAT1, CAT2, EAAT3, LAT1, y(+)LAT1 and y(+)LAT2), sugar transporters (GLUT1, GLUT2, GLUT5 and SGLT1), zinc transporter (ZnT1) and an antimicrobial peptide (LEAP2). Duodenum, jejunum, ileum and ceca were collected 7 days post challenge. E. acervulina challenge resulted in downregulation of various nutrient transporters or LEAP2 in the duodenum and ceca, but not the jejunum or ileum. E. maxima challenge produced both downregulation and upregulation of nutrient transporters and LEAP2 in all three segments of the small intestine and ceca. E. tenella challenge resulted in the downregulation and upregulation of nutrient transporters and LEAP2 in the jejunum, ileum and ceca, but not the duodenum. At the respective target tissue, E. acervulina, E. maxima and E. tenella infection caused common downregulation of APN, b(0,+)AT, rBAT, EAAT3, SI, GLUT2, GLUT5, ZnT1 and LEAP2. The downregulation of nutrient transporters would result in a decrease in the efficiency of protein and polysaccharide digestion and uptake, which may partially explain the weight loss. The downregulation of nutrient transporters may also be a cellular response to reduced expression of the host defense protein LEAP2, which would diminish intracellular pools of nutrients and inhibit pathogen replication.


Assuntos
Ceco/parasitologia , Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/fisiologia , Intestino Delgado/parasitologia , Doenças das Aves Domésticas/metabolismo , Animais , Ceco/enzimologia , Ceco/metabolismo , Coccidiose/enzimologia , Coccidiose/metabolismo , Regulação para Baixo , Eimeria/classificação , Regulação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Intestino Delgado/enzimologia , Intestino Delgado/metabolismo , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Doenças das Aves Domésticas/enzimologia , Doenças das Aves Domésticas/parasitologia , Regulação para Cima , Aumento de Peso
19.
Parasitol Res ; 114(6): 2063-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25704645

RESUMO

The purpose of this study was to develop and utilize semi-quantitative RT-PCR and PCR assays for measuring the level of Cryspovirus, the viral symbiont of Cryptosporidium parvum, during in vitro development of the protozoan. Cultures of human carcinoma cells (HCT-8) were inoculated with excysting C. parvum sporozoites, followed by harvest of cells and culture medium at 2-, 24-, 48-, and 72-h post-infection. Changes in viral RNA levels were detected by RT-PCR using primers specific for RNA encoding the 40-kDa capsid protein (CP) or RNA-dependent RNA polymerase (RdRp). Parasite or host DNA was quantified by PCR specific for C. parvum or human glyceraldehyde-3-phosphate dehydrogenase (HuGAPDH). An internal standard (competitor) was incorporated into all assays as a control for PCR inhibition. Intracellular levels of C. parvum DNA increased between 2- and 48-h post-infection, and then decreased at 72 h. Culture medium overlying these C. parvum-infected cells displayed a similar increase in CP and RdRp signal, reaching peak levels at 48 h. However, the CP and RdRp levels in cellular RNA displayed only a modest increase between 2 and 48 h, and exhibited no change (CP) or decreased (RdRp) at 72 h. These data suggest that during the first 48 h of C. parvum in vitro development, Cryspovirus is released into the media overlying cells but remains at fairly constant levels within infected cells.


Assuntos
Cryptosporidium parvum/virologia , Vírus de RNA/isolamento & purificação , Linhagem Celular Tumoral , Cryptosporidium parvum/crescimento & desenvolvimento , Humanos , Reação em Cadeia da Polimerase , RNA Viral/genética
20.
Poult Sci ; 94(7): 1521-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26015586

RESUMO

Coccidiosis is a major intestinal disease of poultry, caused by several species of the protozoan Eimeria. The objective of this study was to examine changes in expression of digestive enzymes, nutrient transporters, and an antimicrobial peptide following an Eimeria praecox challenge of chickens at days 3 and 6 post-infection. Gene expression was determined by real-time PCR and analyzed by one-way ANOVA. In the duodenum, the primary site of E. praecox infection, a number of genes were downregulated at both d3 and d6 post-infection. These genes included liver expressed antimicrobial peptide 2 (LEAP2), the cationic (CAT1), anionic (EAAT3), and L-type (LAT1) amino acid transporters, the peptide transporter PepT1 and the zinc transporter ZnT1. Other transporters were downregulated either at d3 or d6. At both d3 and d6, there was downregulation of B(o)AT and CAT1 in the jejunum and downregulation of LEAP2 and LAT1 in the ileum. LEAP2, EAAT3, and ZnT1 have been found to be downregulated following challenge with other Eimeria species, suggesting a common cellular response to Eimeria.


Assuntos
Galinhas , Coccidiose/veterinária , Eimeria/fisiologia , Regulação da Expressão Gênica , Hepcidinas/genética , Proteínas de Membrana Transportadoras/genética , Doenças das Aves Domésticas/genética , Animais , Coccidiose/genética , Coccidiose/metabolismo , Coccidiose/parasitologia , Hepcidinas/metabolismo , Intestinos/enzimologia , Intestinos/parasitologia , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/parasitologia , Reação em Cadeia da Polimerase em Tempo Real
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