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1.
JBJS Case Connect ; 14(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38517980

RESUMO

CASE: We report a single case of a closed intra-articular distal humerus fracture in a 28-year-old man with a preexisting fishtail deformity characterized by concavity of the central trochlea and corresponding deformity of the olecranon. The patient was treated with open reduction and internal fixation. CONCLUSION: The case highlights the diagnosis and challenges of treatment. Conventional fixation choices and imaging techniques may need to be altered when treating a fracture with this deformity.


Assuntos
Articulação do Cotovelo , Fraturas Distais do Úmero , Fraturas do Úmero , Olécrano , Masculino , Humanos , Adulto , Fraturas do Úmero/complicações , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Fixação Interna de Fraturas , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/cirurgia , Olécrano/diagnóstico por imagem
2.
Clin Cardiol ; 47(1): e24200, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38183320

RESUMO

BACKGROUND: Cognitive impairment is highly prevalent among patients with heart failure (HF). International guidelines on the management of HF recommend screening for cognitive impairment and tailored care for patients with cognitive impairment. However, practical guidance is lacking. In this study, we explore cardiologists' perspective on screening and care for cognitive impairment in patients with HF. We give an example of a multidisciplinary Heart-Brain care pathway that facilitates screening for cognitive impairment in patients with HF. METHODS: We distributed an online survey to cardiologists from the Dutch working groups on Geriatric Cardiology and Heart Failure. It covered questions about current clinical practice, impact of cognitive impairment on clinical decision-making, and their knowledge and skills to recognize cognitive impairment. RESULTS: Thirty-six out of 55 invited cardiologists responded. Only 3% performed structured cognitive screening, while 83% stated that not enough attention is paid to cognitive impairment. More than half of the cardiologists desired more training in recognizing cognitive impairment and three-quarters indicated that knowing about cognitive impairment would change their treatment plan. Eighty percent agreed that systematic cognitive screening would benefit their patients and 74% wished to implement a Heart-Brain clinic. Time and expertise were addressed as the major barriers to screening for cognitive impairment. CONCLUSION: Although cardiologists are aware of the clinical relevance of screening for cognitive impairment in cardiology patients, such clinical conduct is not yet commonly practiced due to lack of time and expertise. The Heart-Brain care pathway could facilitate this screening, thus improving personalized care in cardiology.


Assuntos
Cardiologia , Insuficiência Cardíaca , Humanos , Idoso , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Inquéritos e Questionários , Encéfalo , Cognição
3.
Brain ; 147(1): 26-38, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-37633259

RESUMO

Restless legs syndrome (RLS) is responsive to opioid, dopaminergic and iron-based treatments. Receptor blocker studies in RLS patients suggest that the therapeutic efficacy of opioids is specific to the opioid receptor and mediated indirectly through the dopaminergic system. An RLS autopsy study reveals decreases in endogenous opioids, ß-endorphin and perhaps Met-enkephalin in the thalamus of RLS patients. A total opioid receptor knock-out (mu, delta and kappa) and a mu-opioid receptor knock-out mouse model of RLS show circadian motor changes akin to RLS and, although both models show sensory changes, the mu-opioid receptor knock mouse shows circadian sensory changes closest to those seen in idiopathic RLS. Both models show changes in striatal dopamine, anaemia and low serum iron. However, only in the total receptor knock-out mouse do we see the decreases in serum ferritin that are normally found in RLS. There are also decreases in serum iron when wild-type mice are administered a mu-opioid receptor blocker. In addition, the mu-opioid receptor knock-out mouse also shows increases in striatal zinc paralleling similar changes in RLS. Adrenocorticotropic hormone and α-melanocyte stimulating hormone are derived from pro-opiomelanocortin as is ß-endorphin. However, they cause RLS-like symptoms and periodic limb movements when injected intraventricularly into rats. These results collectively suggest that an endogenous opioid deficiency is pathogenetic to RLS and that an altered melanocortin system may be causal to RLS as well.


Assuntos
Analgésicos Opioides , Síndrome das Pernas Inquietas , Humanos , Ratos , Camundongos , Animais , Analgésicos Opioides/farmacologia , Analgésicos Opioides/uso terapêutico , Síndrome das Pernas Inquietas/diagnóstico , Síndrome das Pernas Inquietas/tratamento farmacológico , Melanocortinas/uso terapêutico , beta-Endorfina/uso terapêutico , Ferro , Dopamina
4.
Curr Probl Diagn Radiol ; 53(1): 68-72, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37704486

RESUMO

PURPOSE: MRI is the preferred imaging modality for primary staging of rectal cancer, used to guide treatment. Patients identified with clinical stage I disease receive upfront surgical resection; those with clinical stage II or greater undergo upfront neoadjuvant therapy. Although clinical under-/over-staging may have consequences for patients and presents opportunities for organ preservation, the correlation between clinical and pathologic staging in routine clinical practice within a single institute has not been fully established. METHODS: This retrospective, Institutional Review Board-approved study, conducted at a National Cancer Institute-Designated Comprehensive Cancer Center with a multi-disciplinary rectal cancer disease center, included patients undergoing rectal MRI for primary staging January 1, 2018-August 30, 2020. Data collection included patient demographics, initial clinical stage via MRI report, pathologic diagnosis, pathologic stage, and treatment. The primary outcome was concordance of overall clinical and pathologic staging. Secondary outcomes included reasons for mismatched staging. RESULTS: A total 105 rectal adenocarcinoma patients (64 males, mean age 57 ± 12.7 years) had staging MRI followed by surgical resection. A total of 28 patients (27%) had mismatched under-/over- staging. Ten patients (10%) were understaged with mismatched T stage group (clinical stage I, pathologic stage II), five (5%) were understaged with mismatched N stage group (clinical stage I, pathologic stage III), and 13 (12%) were overstaged (clinical stage II-III, pathologic stage 0-I). Treatment matched concordance between clinical and pathologic stages was 86%. CONCLUSION: MRI for primary rectal cancer staging has high concordance with pathology. Future studies to assess strategies for reducing clinically relevant understaging would be beneficial.


Assuntos
Neoplasias Retais , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Reto/diagnóstico por imagem , Terapia Neoadjuvante , Estadiamento de Neoplasias , Imageamento por Ressonância Magnética/métodos
5.
Brain Stimul ; 16(6): 1764-1775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38061548

RESUMO

Identifying functional biomarkers related to treatment success can aid in expediting therapy optimization, as well as contribute to a better understanding of the neural mechanisms of the treatment-resistant depression (TRD) and subcallosal cingulate deep brain stimulation (SCC-DBS). Magnetoencephalography data were obtained from 16 individuals with SCC-DBS for TRD and 25 healthy subjects. The first objective of the study was to identify region-specific oscillatory modulations that both (i) discriminate individuals with TRD (with SCC-DBS OFF) from healthy controls, and (ii) discriminate TRD treatment responders from non-responders (with SCC-DBS ON). The second objective of this work was to further explore the effects of stimulation intensity and frequency on oscillatory activity in the identified brain regions of interest. Oscillatory power analyses led to the identification of brain regions that differentiated responders from non-responders based on modulations of increased alpha (8-12 Hz) and decreased gamma (32-116 Hz) power within nodes of the default mode, central executive, and somatomotor networks, Broca's area, and lingual gyrus. Within these nodes, it was also found that low stimulation frequency had stronger effects on oscillatory modulation than increased stimulation intensity. The identified functional network biomarkers implicate modulation of TRD-related activity in brain regions involved in emotional control/processing, motor control, and the interaction between speech, vision, and memory, which have all been implicated in depression. These electrophysiological biomarkers have the potential to be used as functional proxies for therapy optimization. Additional stimulation parameter analyses revealed that oscillatory modulations can be strengthened by increasing stimulation intensity or reducing frequency, which may represent potential avenues of direction in non-responders.


Assuntos
Estimulação Encefálica Profunda , Transtorno Depressivo Resistente a Tratamento , Humanos , Giro do Cíngulo/fisiologia , Depressão , Resultado do Tratamento , Transtorno Depressivo Resistente a Tratamento/terapia , Biomarcadores
6.
Geriatr Orthop Surg Rehabil ; 14: 21514593231204760, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37867607

RESUMO

Background: Hip fractures in the geriatric population are frequently encountered. There is increasing focus on minimizing the delay to surgery in these patients. This study was designed to evaluate factors responsible for a delay to surgery in a geriatric hip fracture population and how time to surgery affects mortality. Methods: A retrospective cohort of patients sustaining low energy geriatric hip fractures in either an American College of Surgeons (ACS) verified Level 1 trauma center or a local university affiliated community teaching hospital were reviewed. The following variables were evaluated as independent risk factors for delay to surgery: demographic data, surgical details, use of cardiology resources, treatment center, and comorbidities. As a secondary objective, the effect of time to surgery on 1 year mortality was analyzed. Results: 1157 patients met inclusion criteria. The following factors increased the risk of delay to surgery greater than 48 hours: male sex, treatment in a community hospital (versus trauma center), older age, multiple comorbidities (eg, cardiovascular-related conditions or other fractures), cardiology consultation, and an American Society of Anesthesiologists physical status score of 3 or 4. Cardiology consultation was the strongest independent predictor of risk for delay to surgery of >48 hours (odds ratio, 6.68; 95% confidence interval, 4.40 to 10.14; P < .001). The 1-year mortality of patients did not differ when surgical treatment occurred before 48 hours or after 48 hours (Log-rank test P = .109). Conclusion: The presence of cardiovascular comorbidities and cardiology consultations can delay surgical treatments for hip fractures in patients greater than 65 years old, but the delay did not influence 1-year all-cause mortality. Level of Evidence: Level IV.

7.
Heliyon ; 9(7): e17574, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37449171

RESUMO

We study a generalization of the static model of [11] with two risk neutral insiders to the case where each insider is partially informed about the value of the stock. First, we provide a necessary and sufficient condition for the uniqueness of the linear Bayesian equilibrium. Specifically, we show that, when the covariance matrix of the errors terms of the insiders' signals, is not singular, the linear Bayesian equilibrium is not unique. Then, we carry out a comparative statics analysis.

8.
JBJS Case Connect ; 13(2)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37262196

RESUMO

CASE: We report a case of a rare "floating fibula" ankle injury characterized by dislocation of the proximal tibiofibular joint (PTFJ), syndesmosis disruption, complete deltoid disruption, and tibiotalar dislocation without fibula fracture in a 44-year-old man. Imaging includes preoperative and postoperative radiographs and CT scans. Treatment involved reduction and screw fixation of the syndesmosis and PTFJ with planned screw removal. A successful clinical and radiographic outcome was achieved at the 15-month follow-up. CONCLUSION: This case highlights the unique features of the "floating fibula" injury and shows that reduction and intraoperative assessment may be more challenging than a typical Maisonneuve injury.


Assuntos
Traumatismos do Tornozelo , Fraturas Ósseas , Masculino , Humanos , Adulto , Fíbula/diagnóstico por imagem , Fíbula/cirurgia , Fíbula/lesões , Fixação Interna de Fraturas , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos do Tornozelo/cirurgia , Resultado do Tratamento
9.
J Clin Sleep Med ; 19(6): 1083-1088, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36747495

RESUMO

STUDY OBJECTIVES: Sleep fellowship program websites likely serve as a preliminary source of information for prospective fellows. Arguably, applicants have likely become even more reliant on program websites during the COVID-19 pandemic due to travel restrictions and social-distancing measures limiting in-person interviews. In this study, we evaluated the content and comprehensiveness of sleep medicine fellowship websites to identify areas of improvement. METHODS: A list of sleep medicine fellowship programs in the United States participating in the 2021 match cycle was compiled using the Electronic Residency Application Service (ERAS) and Fellowship and Residency Electronic Interactive database (FREIDA) websites. Twenty-two prespecified content criteria related to education, recruitment, and compensation were used to evaluate each program website. Sleep programs' website comprehensiveness were compared based on US location, type, matching status, core specialty, and size of programs. RESULTS: Seventy-eight US sleep fellowship program websites were evaluated. Most program websites had a working hyperlink on ERAS or FREIDA. There was considerable variability in content reported across program websites, with a mean of 56.8% of content items reported per program. There was a greater educational website content comprehensiveness for internal medicine compared with other specialty-based sleep programs. There was no difference in sleep programs' website comprehensiveness based on US location, type, matching status, or size of programs. CONCLUSIONS: Website content comprehensiveness among sleep fellowship programs is variable. There is opportunity for all sleep fellowship programs to improve their websites to better inform prospective trainees. CITATION: Shenoy S, Akberzie W, Landeo-Gutierrez JS, Leon Guerrero CR, Karroum EG. Evaluation of sleep medicine fellowship program websites. J Clin Sleep Med. 2023;19(6):1083-1088.


Assuntos
COVID-19 , Internato e Residência , Humanos , Estados Unidos , Bolsas de Estudo , Pandemias , Estudos Prospectivos , Educação de Pós-Graduação em Medicina , Internet
10.
Acta Vet Scand ; 65(1): 2, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36703227

RESUMO

BACKGROUND: Canine leishmaniosis (CanL) is a systemic disease caused by the protozoan parasite Leishmania infantum with a wide spectrum of clinical signs, with cutaneous, ocular, renal and lymphoreactive conditions prevailing in the clinical setting. The immune system plays a pivotal role in the evolution of Leishmania infection and its response to antileishmanial treatment. Cytokines are important immune response mediators that are released by activated lymphocytes and less so by other immunocytes. In dogs with leishmaniosis, IFN-γ and IL-4 have been recognized as the main activators of cellular and humoral immunity, respectively. The objective of this study was to investigate intracellular IL-4 and IFN-γ expression by CD4 + and CD8 + lymphocytes in the peripheral blood of symptomatic dogs before and after combined antileishmanial treatment with miltefosine and allopurinol. RESULTS: Postantileishmanial treatment CD4 + IL-4 + and CD8 + IL-4 + cell counts were significantly decreased, although no similar changes were observed in the comparisons made between the pre- and posttreatment CD4 + IFN-γ + and CD8 + IFN-γ + counts and ratios. CONCLUSION: The findings indicate that IL-4 production by T cells may facilitate the symptomatic phase of CanL, whereas IFN-γ production by CD4 + and CD8 + cells may indicate its negligible role in the evolution of natural CanL and perhaps the equivocal positive influence of antileishmanial treatment.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Cães , Interleucina-4 , Estudos Transversais , Alopurinol/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/veterinária , Interferon gama , Linfócitos T CD8-Positivos
11.
Clin Pharmacol Ther ; 113(3): 600-606, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36325997

RESUMO

The relationship between race and biology is complex. In contemporary medical science, race is a social construct that is measured via self-identification of study participants. But even though race has no biological essence, it is often used as variable in medical guidelines (e.g., treatment recommendations specific for Black people with hypertension). Such recommendations are based on clinical trials in which there was a significant correlation between self-identified race and actual, but often unmeasured, health-related factors such as (pharmaco)genetics, diet, sun exposure, etc. Many teachers are insufficiently aware of this complexity. In their classes, they (unintentionally) portray self-reported race as having a biological essence. This may cause students to see people of shared race as biologically or genetically homogeneous, and believe that race-based recommendations are true for all individuals (rather than reflecting the average of a heterogeneous group). This medicalizes race and reinforces already existing healthcare disparities. Moreover, students may fail to learn that the relation between race and health is easily biased by factors such as socioeconomic status, racism, ancestry, and environment and that this limits the generalizability of race-based recommendations. We observed that the clinical case vignettes that we use in our teaching contain many stereotypes and biases, and do not generally reflect the diversity of actual patients. This guide, written by clinical pharmacology and therapeutics teachers, aims to help our colleagues and teachers in other health professions to reflect on and improve our teaching on race-based medical guidelines and to make our clinical case vignettes more inclusive and diverse.


Assuntos
Farmacologia Clínica , Racismo , Humanos , Estudantes , Classe Social , Aprendizagem
12.
Curr Probl Diagn Radiol ; 52(2): 110-116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36333220

RESUMO

PURPOSE: The aim of this study was to analyze chest CT imaging findings and relevant clinical factors in patients with HIV presenting to the emergency department (ED). MATERIALS AND METHODS: A retrospective review was performed to identify patients with HIV who received chest CT imaging evaluation in the acute ED setting. Analyzed patients included adults with a known diagnosis of HIV who presented to the ED at a single tertiary care center between 2004 and 2020 and received chest CT imaging. Chest CT findings were assessed by 2 radiologist readers, and relevant clinical data were gathered. Statistical analysis was performed to determine if imaging and clinical factors demonstrate significant associations with CD4 count, viral load, and antiretroviral therapy status. RESULTS: A total of 113 patients with HIV were identified who presented to the ED and underwent chest CT imaging evaluation (mean age 47 ± 11 years). Frequently detected chest CT findings included infectious pneumonia (24%), malignancy (11%), pleural effusion (17%), pericardial effusion (13%), and pulmonary embolism (4%). CD4 count, viral load, and active retroviral therapy demonstrated statistically significant associations with a number of key imaging and clinical factors, including presence of pneumonia, malignancy, average length of hospital admission, and survival. CONCLUSION: Patients with HIV present with a wide range of imaging findings when presenting in the acute ED setting. CD4 count, viral load, and active retroviral therapy status demonstrate statistically significant associations with multiple key imaging findings and clinical factors. Chest CT plays an integral role in the clinical management of this unique patient population.


Assuntos
Infecções por HIV , Pneumonia , Adulto , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Estudos Retrospectivos , Serviço Hospitalar de Emergência , Infecções por HIV/diagnóstico por imagem , Infecções por HIV/complicações
13.
Curr Probl Diagn Radiol ; 52(4): 257-262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36481296

RESUMO

OBJECTIVE: To assess emergency department (ED) abdominopelvic computed tomography (CT) imaging utilization and findings in patients with known human immunodeficiency virus (HIV) positive status. MATERIALS AND METHODS: A retrospective chart review of imaging, clinical, and laboratory data was performed for HIV positive patients who demonstrated HIV-related findings on abdominopelvic CT imaging performed within the ED. RESULTS: One hundred and eighty-eight patients with 522 CT scans of the abdomen and/or pelvis were reviewed. 47 patients with HIV presenting to the ED on 82 separate occasions were included in this study (mean age 43.3 years). Patients presented to the ED with infectious/inflammatory disease (n = 54) or history of HIV-related malignancy or new/worsening HIV-related malignancy (n = 28). The most common findings on abdominopelvic CT were anorectal pathology including anorectal abscess or proctitis (n = 22), followed by colitis (n = 19). Findings of HIV-associated malignancy were less common, including anal/rectal cancer (n = 7), Kaposi's sarcoma (n = 4), and lymphoma (n = 2). At the time of ED visit, 25.6% (n = 21) of patients had acquired immunodeficiency syndrome (AIDS). Higher WBC counts were found in the infectious/inflammatory group (P = 0.021) and patients without AIDS (P = 0.0159), while lower WBC counts were associated with new or worsening malignancy (P = 0.007) and AIDS (P = 0.0000). Patients with AIDS were more likely to be deceased at the time of our study. CONCLUSIONS: The majority of ED visits within our population were attributed to infectious/inflammatory etiologies. CT findings demonstrated predominantly infectious/inflammatory processes, with anorectal pathology being the most common. Findings of malignancy on CT were less common, while opportunistic infections and AIDS-defining malignancies were uncommon.


Assuntos
Síndrome da Imunodeficiência Adquirida , Neoplasias , Humanos , Adulto , Síndrome da Imunodeficiência Adquirida/complicações , Estudos Retrospectivos , Serviço Hospitalar de Emergência , Tomografia Computadorizada por Raios X/métodos
14.
Med Hypotheses ; 1672022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36505961

RESUMO

Restless Legs Syndrome (RLS) is characterized by bothersome leg discomfort accompanied by an urge to move to obtain relief and symptoms are worse at night and on lying down. There is at least partial and temporary relief with activity. It is also an opioid responsive disorder, often accompanied by iron deficiency with or without anemia, and inflammation may be a precipitating factor in some cases. We created two in-vivo opiate receptor knock out mouse models of RLS - a triple opiate receptor knock-out mouse and a mu opiate receptor knock-out mouse. Both sets of animals were restless during the sleep period as is also true of RLS. Both of our knockout models showed statistically significantly decreased Hemoglobin and Hematocrit indicating anemia and both models showed statistically significant decreases in serum iron suggestive of either iron deficiency anemia or inflammatory anemia. The rest of the hematologic studies were not consistent enough to determine which of these two types of anemia was present in either model. An additional experiment in normal wild type mice showed a statistically significant decrease in serum iron when an opiate receptor blocker was used. To our knowledge this is the first demonstration that deficiency of endogenous opioids might play a role in the production of anemia. Our hypothesis is that an intact endogenous opiate system is necessary for red cell homeostasis. The presence of opioid receptors both on red blood cells and on various immunologically based white blood cells suggest mechanisms by which deficiency in the endogenous opiate system could cause anemia of either the iron deficiency or inflammatory types. The administration of opioid agonists or antagonists to iron deficient cultures of red blood cell precursors is a next step in determining the role of the endogenous opiate system in the maintenance of red cell homeostasis and in the possible prevention of iron deficiency or inflammatory anemia where iron dysregulation is key.

15.
BAG, J. basic appl. genet. (Online) ; 33(1): 71-81, Oct. 2022. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420287

RESUMO

ABSTRACT Turnera sidoides (x=7) is one of the few well-studied South American autopolyploid complexes. Since polyploidy has played a prominent role within this complex, ongoing studies in T. sidoides focus on understanding the mechanisms involved in the origin and the establishment of polyploids using integrative approaches. This paper synthesises the results of more than 20 years of research on this topic. Cytogenetics analysis provided evidences for the production of unreduced male and female gametes, supporting the hypothesis of bilateral sexual polyploidization as the mechanism of origin of polyploids in T. sidoides. The finding of viable triploids suggested that unilateral sexual polyploidization could also be an important mechanism for the origin of tetraploids in T. sidoides. The occurrence of plants continuously forming many unreduced gametes would play a key role in the establishment of neopolyploids in natural populations. Also, the higher number of propagules that tetraploids contribute to subsequent generations, the ability to multiply asexually by rhizomes, and the occurrence of occasional cases of self-compatibility and successful illegitimate crosses in polyploids increase the likelihood that a low frequency of neopolyploids can be maintained in natural populations of T. sidoides. In addition, integration of cytogeographic and genetic divergence data together with past niche modelling provided further insights supporting the hypothesis that historical climatic and geomorphological events provided favourable conditions for the establishment of autopolyploids, with the wider distribution of tetraploids of T. sidoides being the result of their range expansion.


RESUMEN Turnera sidoides (x=7) es uno de los pocos complejos autopoliploides sudamericanos bien estudiados. Como la poliploidía ha tenido un papel destacado en el complejo, los estudios en curso en T. sidoides se centraron en la comprensión de los mecanismos implicados en el origen y el establecimiento de los poliploides mediante diferentes enfoques. En este trabajo se sintetizan los resultados de más de 20 años de investigación sobre este tema. El análisis citogenético proporcionó evidencias de la producción de gametos masculinos y femeninos no reducidos, sustentando la hipótesis de la poliploidización sexual bilateral como mecanismo de origen de los poliploides en T. sidoides. Sin embargo, el hallazgo de triploides fértiles sugirió que la poliploidización sexual unilateral también sería un mecanismo importante de origen de tetraploides en T. sidoides. La ocurrencia de plantas que forman continuamente gametos no reducidos desempeñaría un papel clave en el establecimiento de neopoliploides. Además, el mayor número de propágulos que los tetraploides aportan a las siguientes generaciones, la capacidad de multiplicación asexual por rizomas y los casos ocasionales de autocompatibilidad y cruzamientos ilegítimos exitosos aumentarían la probabilidad de que se mantenga una baja frecuencia de neopoliploides en las poblaciones naturales de T. sidoides. Asimismo, la integración de datos citogeográficos y de divergencia genética junto con el modelado de nicho en el pasado aportó información que sustenta la hipótesis de que los eventos climáticos y geomorfológicos históricos proporcionaron las condiciones favorables para el establecimiento y expansión de los tetraploides de T. sidoides.

16.
Arch Microbiol ; 204(10): 610, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36085198

RESUMO

Aliarcobacter butzleri (formerly known as Arcobacter butzleri) is an emerging food-borne zoonotic pathogen that establishes in vitro endosymbiotic relationships with Acanthamoeba castellanii, a free-living amoeba. Previously, we described that this bacterium acts as an endocytobiont of A. castellanii, surviving for at least 10 days in absence of bacterial replication. Thus, the aim of this study was to evaluate the ability of A. butzleri to survive as a long-term endosymbiont of A. castellanii for 30 days in two models of symbiotic interaction with A. castellanii: (i) endosymbiotic culture followed by gentamicin protection assay and (ii) transwell co-culture assay. The results allow us to conclude that A. butzleri is capable of surviving as an endosymbiont of A. castellanii for at least 30 days, without multiplying, under controlled laboratory conditions. In addition, in the absence of nutrients and as both microorganisms remain in the same culture, separated by semi-permeable membranes, A. castellanii does not promote the survival of A. butzleri, nor does it multiply. Our findings suggest that the greater survival capacity of A. butzleri is associated with their endosymbiont status inside A. castellanii, pointing out the complexity of this type of symbiotic relationship.


Assuntos
Acanthamoeba castellanii , Arcobacter , Acanthamoeba castellanii/microbiologia , Simbiose
17.
J Shoulder Elb Arthroplast ; 6: 24715492221127686, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157844

RESUMO

Background: To evaluate the clinical, functional, radiographic, and survival outcomes in patients undergoing reverse total shoulder arthroplasty (RSA) with uncemented stem fixation for proximal humerus fractures. Materials and Methods: This is a retrospective cohort study that evaluated a consecutive series of patients with proximal humerus fractures undergoing RSA. Clinical data, radiographs, and re-operation rates were reviewed in patients selected for uncemented stem fixation. The same parameters were compared to the remainder of the cohort undergoing cemented stem fixation. Results: The uncemented group (n = 16, median total follow-up = 108 weeks) and cemented group (n = 12, median total follow-up = 223 weeks, p = 0.110) did not differ statistically in pre-operative demographic, post-operative outcomes or incidence of complications. Two patients (12.5%) in the uncemented group required a reoperation (Week 52 and 180) versus none in the cemented group. Conclusion: Uncemented stem fixation in RSA for proximal humerus fractures does not yield worse results than cemented stem fixation in properly selected patients. Prospective non-inferiority trials comparing outcomes are recommended.

18.
Front Aging Neurosci ; 14: 885787, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35837485

RESUMO

Introduction: Globally, women with dementia have a higher disease burden than men with dementia. In addition, women with diabetes especially are at higher risk for cognitive impairment and dementia compared to men with diabetes. Differences in the influence of diabetes on the cerebral vasculature and brain structure may contribute to these sex-specific differences. We examined sex-specific patterns in the relationship between diabetes and brain structure, as well as diabetes and cognitive function. Methods: In total, 893 patients [age 79 ± 6.6 years, 446 (50%) women] from the Amsterdam Ageing Cohort with available data on brain structures (assessed by an MRI or CT scan) and cognitive function were included. All patients underwent a thorough standardized clinical and neuropsychological assessment (including tests on memory, executive functioning, processing speed, language). Brain structure abnormalities were quantified using visual scales. Results: Cross-sectional multivariable regression analyses showed that diabetes was associated with increased incidence of cerebral lacunes and brain atrophy in women (OR 2.18 (1.00-4.72) but not in men. Furthermore, diabetes was associated with decreased executive function, processing speed and language in women [B -0.07 (0.00-0.13), -0.06 (0.02-0.10) and -0.07 (0.01-0.12) resp.] but not in men. Conclusions: Diabetes is related to increased risk of having lacunes, brain atrophy and impaired cognitive function in women but not in men. Further research is required to understand the time trajectory leading up to these changes and to understand the mechanisms behind them in order to improve preventive health care for both sexes.

19.
J Comput Assist Tomogr ; 46(4): 621-632, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35675685

RESUMO

ABSTRACT: Treatment strategies for malignant melanoma have rapidly evolved over the past decade. Because of its propensity to develop advanced stage and metastatic disease, melanoma has contributed to the majority of mortalities among patients with skin cancer. The development of novel therapeutics such as immunotherapy and targeted molecular therapies has revolutionized the treatment of patients with advanced stage and metastatic malignant melanoma. Immune checkpoint inhibitors, BRAF/MEK inhibitors, and other revolutionary therapies have demonstrated remarkable success in the treatment of this common malignancy. Along with these advancements in systemic therapies, imaging has continued to play a critical role in the diagnosis and follow-up of patients with malignant melanoma. As the use of these novel therapies continues to expand, knowledge of the evolving therapeutic landscape of melanoma is becoming critical for radiologists. In this review, we provide a primer for radiologists outlining the evolution of immunotherapy and targeted therapy in the treatment of melanoma. We discuss the critical role of imaging in evaluation of treatment response, including a summary of current imaging response guidelines. Last, we summarize the essential role of imaging in the evaluation of potential adverse events seen in patients with malignant melanoma undergoing treatment with immune checkpoint inhibitors.


Assuntos
Antineoplásicos , Melanoma , Neoplasias Cutâneas , Antineoplásicos/uso terapêutico , Humanos , Inibidores de Checkpoint Imunológico , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Melanoma/terapia , Radiologistas , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/tratamento farmacológico , Melanoma Maligno Cutâneo
20.
J R Soc Interface ; 19(189): 20210913, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35382574

RESUMO

This study describes analytically the behaviour of bamboo culms subjected to bending, and predicts the failure load and stiffness loss after the linear-elastic stage. Basis of the failure load prediction is the identification of the critical failure mechanisms. The study examines analytically four distinct failure mechanisms: Brazier instability, longitudinal tension/compression, tension perpendicular to the fibres and shear parallel to the fibres. It concludes that, for the three bamboo species examined (Moso, Guadua and Kao Jue), critical failure mechanisms are tension perpendicular to the fibres (with potential tension-shear interaction) and longitudinal compression. Which of the two mechanisms occurs first depends on the case-specific material properties and culm radius-to-thickness ratio. Regarding stiffness loss, the main cause is longitudinal splitting. The extent of the stiffness loss depends on crack length, crack number and crack location along the culm circumference. Secondary causes are nonlinear geometric effects at the large deflection stage. Assuming a parabolic deformed shape, a single equation can describe the stiffness loss induced by nonlinear geometric effects, regardless of material properties and culm geometry. Comparing the analytical results with pertinent experimental data, the proposed equations are sufficiently accurate in their prediction of failure load and stiffness loss, although they tend to underestimate both.


Assuntos
Poaceae
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