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2.
Phys Rev Lett ; 130(3): 031802, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36763398

RESUMO

We report a search for cosmic-ray boosted dark matter with protons using the 0.37 megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1 MeV/c^{2} to 300 MeV/c^{2}.

3.
BMJ ; 365: l2006, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088853

RESUMO

CLINICAL QUESTION: What are the benefits and harms of thyroid hormones for adults with subclinical hypothyroidism (SCH)? This guideline was triggered by a recent systematic review of randomised controlled trials, which could alter practice. CURRENT PRACTICE: Current guidelines tend to recommend thyroid hormones for adults with thyroid stimulating hormone (TSH) levels >10 mIU/L and for people with lower TSH values who are young, symptomatic, or have specific indications for prescribing. RECOMMENDATION: The guideline panel issues a strong recommendation against thyroid hormones in adults with SCH (elevated TSH levels and normal free T4 (thyroxine) levels). It does not apply to women who are trying to become pregnant or patients with TSH >20 mIU/L. It may not apply to patients with severe symptoms or young adults (such as those ≤30 years old). HOW THIS GUIDELINE WAS CREATED: A guideline panel including patients, clinicians, and methodologists produced this recommendation in adherence with standards for trustworthy guidelines using the GRADE approach. THE EVIDENCE: The systematic review included 21 trials with 2192 participants. For adults with SCH, thyroid hormones consistently demonstrate no clinically relevant benefits for quality of life or thyroid related symptoms, including depressive symptoms, fatigue, and body mass index (moderate to high quality evidence). Thyroid hormones may have little or no effect on cardiovascular events or mortality (low quality evidence), but harms were measured in only one trial with few events at two years' follow-up. UNDERSTANDING THE RECOMMENDATION: The panel concluded that almost all adults with SCH would not benefit from treatment with thyroid hormones. Other factors in the strong recommendation include the burden of lifelong management and uncertainty on potential harms. Instead, clinicians should monitor the progression or resolution of the thyroid dysfunction in these adults. Recommendations are made actionable for clinicians and their patients through visual overviews. These provide the relative and absolute benefits and harms of thyroid hormones in multilayered evidence summaries and decision aids available in MAGIC (https://app.magicapp.org/) to support shared decisions and adaptation of this guideline.


Assuntos
Hipotireoidismo/tratamento farmacológico , Hormônios Tireóideos/uso terapêutico , Adulto , Idoso , Índice de Massa Corporal , Tomada de Decisões , Técnicas de Apoio para a Decisão , Depressão/tratamento farmacológico , Depressão/etiologia , Fadiga/tratamento farmacológico , Fadiga/etiologia , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/complicações , Hipotireoidismo/diagnóstico , Qualidade de Vida , Hormônios Tireóideos/efeitos adversos , Tireotropina/sangue , Tiroxina/sangue , Incerteza
4.
BMJ ; 365: [1-9], May 14, 2019.
Artigo em Inglês | BIGG - guias GRADE | ID: biblio-1094958

RESUMO

What are the benefits and harms of thyroid hormones for adults with subclinical hypothyroidism (SCH)? This guideline was triggered by a recent systematic review of randomised controlled trials, which could alter practice. Current guidelines tend to recommend thyroid hormones for adults with thyroid stimulating hormone (TSH) levels >10 mIU/L and for people with lower TSH values who are young, symptomatic, or have specific indications for prescribing. The guideline panel issues a strong recommendation against thyroid hormones in adults with SCH (elevated TSH levels and normal free T4 (thyroxine) levels). It does not apply to women who are trying tobecome pregnant or patients with TSH >20 mIU/L. It may not apply to patients with severe symptoms or youngadults (such as those ≤30 years old).


Assuntos
Humanos , Adulto , Hormônios Tireóideos/efeitos adversos , Hormônios Tireóideos/uso terapêutico , Hipotireoidismo/complicações , Hipotireoidismo/diagnóstico , Hipotireoidismo/prevenção & controle , Adulto
5.
Clin Endocrinol (Oxf) ; 86(2): 199-206, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27770475

RESUMO

BACKGROUND: In patients with multiple endocrine neoplasia type 1 (MEN-1), pancreaticoduodenal (PD) neuroendocrine tumours (NETs) are associated with early mortality, yet the best treatment strategy remains uncertain. AIM: To assess patient important outcomes (mortality and metastasis) of PD-NETs and predictors of outcomes in patients with MEN-1. METHODS: Retrospective cohort of patients with MEN-1 who attended the Mayo Clinic, Rochester, MN from 1997 to 2014. RESULTS: We identified 287 patients with MEN-1; 199 (69%) patients had 217 PD-NETs. Among those with a PD-NETs, 129 (65%) had surgery of which 90 (70%) had their primary surgery performed at Mayo Clinic. The median postoperative follow-up was 8 years during which 13 (14%) patients died. The mean (±standard deviation) age of death was 51 (±9) years. Tumour size, metastasis at surgery or tumour type were not predictive of mortality, but for every year older at surgery, the odds of metastasis increased by 6%. Surgery was not performed in 70 (35%) patients. Among those who were observed/medically managed without known metastatic disease, mean tumour growth was 0·02 cm/year (range, -0·13-0·4 cm/year). Four patients (7%) died at a median age of 77 (range, 51-89) years. CONCLUSION: PD-NETs are common in patients with MEN-1 and are associated with early mortality even after surgical intervention. Active surveillance is a viable option in nonaggressive PD-NETs, although definitive factors identifying such patients are lacking. Therefore, counselling regarding risks and benefits of current treatment options remains integral to the care of patients with MEN-1.


Assuntos
Neoplasia Endócrina Múltipla Tipo 1/complicações , Tumores Neuroendócrinos/complicações , Neoplasias Pancreáticas/química , Adulto , Estudos de Coortes , Seguimentos , Humanos , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/mortalidade , Neoplasia Endócrina Múltipla Tipo 1/patologia , Metástase Neoplásica , Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/cirurgia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Osteoporos Int ; 27(12): 3395-3407, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27562567

RESUMO

Counseling for patients with primary hyperparathyroidism (PHPT) and mild hypercalcemia without indications for surgical intervention requires accurate estimates of the potential benefits of parathyroidectomy. We aim to summarize the available evidence regarding the benefits of parathyroidectomy that patients with mild PHPT without indications for surgery experience compared to observation. We searched multiple databases from inception to August 2015. We included randomized controlled trials (RCT) and observational studies that evaluated changes in bone health, quality of life or neuropsychiatric symptoms, or in the risk of nephrolithiasis, cardiovascular events, or death between patients undergoing parathyroidectomy or active surveillance. Eight studies were eligible. Risk differences were not significant, in part due to lack of events (fractures, nephrolithiasis, cardiovascular events, or deaths). No significant differences were observed across measures of bone health, quality of life, and neuropsychiatric symptoms. A single RCT evaluating bone mineral density (BMD) changes at 5 years found a small statistically significant effect favoring parathyroidectomy. Patients with mild PHPT without indications for surgery experience a limited number of adverse consequences during short-term follow-up limiting our ability to estimate the benefit of surgery during this timeframe. This information is helpful as these patients consider surgery versus active surveillance. Long-term data is warranted to determine who benefits in the long run from surgical intervention and the extent to which this benefit affects outcomes that matter to patients.


Assuntos
Densidade Óssea , Hiperparatireoidismo Primário/cirurgia , Paratireoidectomia , Humanos , Hipercalcemia/complicações , Estudos Observacionais como Assunto , Qualidade de Vida
7.
ISRN Oncol ; 2014: 530675, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24616820

RESUMO

Prostate cancer (PC) is one of the most common cancers and the second leading cause of mortality from cancer in Colombian men. Mitochondrial DNA (mtDNA) haplogroups have been associated with the risk of PC. Several studies have demonstrated dramatic differences regarding the risk of PC among men from different ethnic backgrounds. The present study was aimed at assessing the relationship between mtDNA haplogroups and PC. The mitochondrial DNA hypervariable segment I (HSV-1) was sequenced in a population-based study covering 168 cases (CA) and 140 unrelated healthy individuals as a control group (CG). A total of 92 different mtDNA sequences were found in CA and 59 were found in the CG. According to the geographical origin attributed to each mtDNA haplogroup, 82% of the mtDNA sequences found in both groups were Native Americans (A, B, C, and D). The most frequent was A (41.1%CA-42.1%CG), followed by B (22.0%CA-21.4%CG), C (12.0%CA-11.4%CG), and D (6%CA-10.0%CG). A lower percentage of European haplogroups (U, H, K, J, M, T, and HV) were also found (13.1%CA-12.9%CG), likewise African haplogroups (L0, L1, L2, and L3) (6.5%CA-2.1%CG). There were no statistically significant differences between the distribution of mtDNA haplogroups in CA and the CG in this study.

8.
J Struct Biol ; 132(1): 1-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11121302

RESUMO

Assembly of nuclear pore complexes (NPCs) is a critical yet poorly understood cellular function. One approach to studying NPC assembly is to identify yeast mutants defective in this process. This requires robust assays for NPC assembly that can be used for phenotypic analysis. We have previously reconstructed yeast nuclei from electron micrographs of serially sectioned cells to precisely determine the number of NPCs (Winey et al., 1997). Here we report the analysis of strains mutant in either of two nucleoporin-encoding genes, NIC96 (Zabel et al., 1996) and NUP192 (Kosova et al., 1999). Using conditional alleles of either gene, we have found that the NPC number falls significantly following shift to the restrictive temperature. We conclude that the drop in NPC number results from the failure to assemble new NPCs during cell divisions, leading to the dilution of NPCs that existed when the cells were shifted to the restrictive temperature. We are also able to document a subtle defect in NPC numbers in nup192-15 cells at their permissive temperature. The data presented here quantitatively demonstrate that NPC numbers fall in nic96-1 and nup192-15 strains upon shifting to the restrictive temperature, indicating that these gene products are required for NPC assembly.


Assuntos
Membrana Nuclear/química , Complexo de Proteínas Formadoras de Poros Nucleares , Poro Nuclear/metabolismo , Proteínas de Saccharomyces cerevisiae , Leveduras/ultraestrutura , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Imageamento Tridimensional , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Mutação , Membrana Nuclear/ultraestrutura , Poro Nuclear/química , Poro Nuclear/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Temperatura , Leveduras/química , Leveduras/genética
9.
Curr Biol ; 10(21): 1375-8, 2000 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11084338

RESUMO

The spindle checkpoint regulates microtubule-based chromosome segregation and helps to maintain genomic stability [1,2]. Mutational inactivation of spindle checkpoint genes has been implicated in the progression of several types of human cancer. Recent evidence from budding yeast suggests that the spindle checkpoint is complex. Order-of-function experiments have defined two separable pathways within the checkpoint. One pathway, defined by MAD2, controls the metaphase-to-anaphase transition and the other, defined by BUB2, controls the exit from mitosis [3-6]. The relationships between the separate branches of the checkpoint, and especially the events that trigger the pathways, have not been defined. We localized a Bub2p-GFP fusion protein to the cytoplasmic side of the spindle pole body and used a kar9 mutant to show that cells with misoriented spindles are arrested in anaphase of mitosis. We used a kar9 bub2 double mutant to show that the arrest is BUB2 dependent. We conclude that the separate pathways of the spindle checkpoint respond to different classes of microtubules. The MAD2 branch of the pathway responds to kinetochore microtubule interactions and the BUB2 branch of the pathway operates within the cytoplasm, responding to spindle misorientation.


Assuntos
Proteínas de Transporte , Proteínas de Ciclo Celular , Proteínas Fúngicas/metabolismo , Genes cdc , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Fuso Acromático/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Ciclo Celular , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Proteínas Fúngicas/genética , Genes Reporter , Proteínas Mad2 , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Fuso Acromático/ultraestrutura , Tubulina (Proteína)/imunologia , Tubulina (Proteína)/metabolismo
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