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1.
Nature ; 606(7913): 281-286, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35585238

RESUMO

Substantial leaps in the understanding of quantum systems have been driven by exploring geometry, topology, dimensionality and interactions in ultracold atomic ensembles1-6. A system where atoms evolve while confined on an ellipsoidal surface represents a heretofore unexplored geometry and topology. Realizing an ultracold bubble-potentially Bose-Einstein condensed-relates to areas of interest including quantized-vortex flow constrained to a closed surface topology, collective modes and self-interference via bubble expansion7-17. Large ultracold bubbles, created by inflating smaller condensates, directly tie into Hubble-analogue expansion physics18-20. Here we report observations from the NASA Cold Atom Lab21 facility onboard the International Space Station of bubbles of ultracold atoms created using a radiofrequency-dressing protocol. We observe bubble configurations of varying size and initial temperature, and explore bubble thermodynamics, demonstrating substantial cooling associated with inflation. We achieve partial coverings of bubble traps greater than one millimetre in size with ultracold films of inferred few-micrometre thickness, and we observe the dynamics of shell structures projected into free-evolving harmonic confinement. The observations are among the first measurements made with ultracold atoms in space, using perpetual freefall to explore quantum systems that are prohibitively difficult to create on Earth. This work heralds future studies (in orbital microgravity) of the Bose-Einstein condensed bubble, the character of its excitations and the role of topology in its evolution.

2.
J Immunol ; 210(12): 2029-2037, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37163328

RESUMO

The intrinsic and acquired resistance to PD-1/PD-L1 immune checkpoint blockade is an important challenge for patients and clinicians because no reliable tool has been developed to predict individualized response to immunotherapy. In this study, we demonstrate the translational relevance of an ex vivo functional assay that measures the tumor cell killing ability of patient-derived CD8 T and NK cells (referred to as "cytotoxic lymphocytes," or CLs) isolated from the peripheral blood of patients with renal cell carcinoma. Patient-derived PBMCs were isolated before and after nephrectomy from patients with renal cell carcinoma. We compared the efficacy of U.S. Food and Drug Administration (FDA)-approved PD-1/PD-L1 inhibitors (pembrolizumab, nivolumab, atezolizumab) and a newly developed PD-L1 inhibitor (H1A Ab) in eliciting cytotoxic function. CL activity was improved at 3 mo after radical nephrectomy compared with baseline, and it was associated with higher circulating levels of tumor-reactive effector CD8 T cells (CD11ahighCX3CR1+GZMB+). Treatment of PBMCs with FDA-approved PD-1/PD-L1 inhibitors enhanced tumor cell killing activity of CLs, but a differential response was observed at the individual-patient level. H1A demonstrated superior efficacy in promoting CL activity compared with FDA-approved PD-1/PD-L1 inhibitors. PBMC immunophenotyping by mass cytometry revealed enrichment of effector CD8 T and NK cells in H1A-treated PBMCs and immunosuppressive regulatory T cells in atezolizumab-treated samples. Our study lays the ground for future investigation of the therapeutic value of H1A as a next-generation immune checkpoint inhibitor and the potential of measuring CTL activity in PBMCs as a tool to predict individual response to immune checkpoint inhibitors in patients with advanced renal cell carcinoma.


Assuntos
Antineoplásicos , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Leucócitos Mononucleares , Antineoplásicos/farmacologia , Linfócitos T Reguladores , Neoplasias Renais/tratamento farmacológico , Nefrectomia , Linfócitos T CD8-Positivos
3.
J Urol ; 211(4): 575-584, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38265365

RESUMO

PURPOSE: The widespread use of minimally invasive surgery generates vast amounts of potentially useful data in the form of surgical video. However, raw video footage is often unstructured and unlabeled, thereby limiting its use. We developed a novel computer-vision algorithm for automated identification and labeling of surgical steps during robotic-assisted radical prostatectomy (RARP). MATERIALS AND METHODS: Surgical videos from RARP were manually annotated by a team of image annotators under the supervision of 2 urologic oncologists. Full-length surgical videos were labeled to identify all steps of surgery. These manually annotated videos were then utilized to train a computer vision algorithm to perform automated video annotation of RARP surgical video. Accuracy of automated video annotation was determined by comparing to manual human annotations as the reference standard. RESULTS: A total of 474 full-length RARP videos (median 149 minutes; IQR 81 minutes) were manually annotated with surgical steps. Of these, 292 cases served as a training dataset for algorithm development, 69 cases were used for internal validation, and 113 were used as a separate testing cohort for evaluating algorithm accuracy. Concordance between artificial intelligence‒enabled automated video analysis and manual human video annotation was 92.8%. Algorithm accuracy was highest for the vesicourethral anastomosis step (97.3%) and lowest for the final inspection and extraction step (76.8%). CONCLUSIONS: We developed a fully automated artificial intelligence tool for annotation of RARP surgical video. Automated surgical video analysis has immediate practical applications in surgeon video review, surgical training and education, quality and safety benchmarking, medical billing and documentation, and operating room logistics.


Assuntos
Prostatectomia , Procedimentos Cirúrgicos Robóticos , Humanos , Masculino , Inteligência Artificial , Escolaridade , Próstata/cirurgia , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Gravação em Vídeo
4.
J Urol ; : 101097JU0000000000004124, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935793

RESUMO

PURPOSE: AUA guidelines prioritize nephron sparing in patients with preexisting chronic kidney disease (CKD). However, few studies analyze long-term renal function in patients with preoperative severe CKD who undergo extirpative renal surgery. Herein, we compare the hazard of progression to end-stage kidney disease (ESKD) following partial nephrectomy (PN) and radical nephrectomy (RN) among patients with preoperative severe CKD. MATERIALS AND METHODS: Patients with stage 4 CKD who underwent PN or RN from 1970 to 2018 were identified. A multivariable Fine-Gray subdistribution hazard model was employed to assess associations with progression to ESKD accounting for the competing risk of death. RESULTS: A total of 186 patients with stage 4 CKD underwent PN (n = 71; 38%) or RN (n = 115; 62%) for renal neoplasms with median follow-up of 6.9 years (interquartile range 3.8-14.1). On multivariable analyses adjusting for competing risk of death, the subdistribution hazard ratio (SHR) for older age at surgery (SHR for 5-year increase 0.81; 95% CI 0.73-0.91; P < .001) and higher preoperative estimated glomerular filtration rate (SHR for 5-unit increase 0.63; 95% CI 0.47-0.84; P = .002) was associated with lower hazard of progression to ESKD. There was no significant difference in hazard of ESKD between PN and RN (SHR 0.82; 95% CI 0.50-1.33; P = .4). CONCLUSIONS: Among patients with preoperative severe CKD, higher preoperative estimated glomerular filtration rate was associated with lower hazard of progression to ESKD after extirpative surgery for renal neoplasms. We did not observe a significant difference in overall hazard for developing ESKD between PN and RN.

5.
J Urol ; 212(2): 331-341, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38813884

RESUMO

PURPOSE: The AUA guidelines introduced a new risk group stratification system based primarily on tumor stage and grade to guide surveillance for patients treated surgically for localized renal cell carcinoma (RCC). We sought to evaluate the predictive ability of these risk groups using progression-free survival (PFS) and cancer-specific survival (CSS), and to compare their performance to that of our published institutional risk models. MATERIALS AND METHODS: We queried our Nephrectomy Registry to identify adults treated with radical or partial nephrectomy for unilateral, M0, clear cell RCC, or papillary RCC from 1980 to 2012. The AUA stratification does not apply to other RCC subtypes as tumor grading for other RCC, such as chromophobe, is not routinely performed. PFS and CSS were estimated using the Kaplan-Meier method. Predictive abilities were evaluated using C indexes from Cox proportional hazards regression models. RESULTS: A total of 3191 patients with clear cell RCC and 633 patients with papillary RCC were included. For patients with clear cell RCC, C indexes for the AUA risk groups and our model were 0.780 and 0.815, respectively (P < .001) for PFS, and 0.811 and 0.857, respectively (P < .001), for CSS. For patients with papillary RCC, C indexes for the AUA risk groups and our model were 0.775 and 0.751, respectively (P = .002) for PFS, and 0.830 and 0.803, respectively (P = .2) for CSS. CONCLUSIONS: The AUA stratification is a parsimonious system for categorizing RCC that provides C indexes of about 0.80 for PFS and CSS following surgery for localized clear cell and papillary RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Nefrectomia , Humanos , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Neoplasias Renais/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Medição de Risco/métodos , Nefrectomia/métodos , Idoso , Estudos Retrospectivos , Estadiamento de Neoplasias , Sistema de Registros , Guias de Prática Clínica como Assunto , Adulto , Taxa de Sobrevida
6.
Am J Kidney Dis ; 84(1): 62-72.e1, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38280640

RESUMO

RATIONALE & OBJECTIVE: Simple kidney cysts, which are common and usually considered of limited clinical relevance, are associated with older age and lower glomerular filtration rate (GFR), but little has been known of their association with progressive chronic kidney disease (CKD). STUDY DESIGN: Observational cohort study. SETTING & PARTICIPANTS: Patients with presurgical computed tomography or magnetic resonance imaging who underwent a radical nephrectomy for a tumor; we reviewed the retained kidney images to characterize parenchymal cysts at least 5mm in diameter according to size and location. EXPOSURE: Parenchymal cysts at least 5mm in diameter in the retained kidney. Cyst characteristics were correlated with microstructural findings on kidney histology. OUTCOME: Progressive CKD defined by dialysis, kidney transplantation, a sustained≥40% decline in eGFR for at least 3 months, or an eGFR<10mL/min/1.73m2 that was at least 5mL/min/1.73m2 below the postnephrectomy baseline for at least 3 months. ANALYTICAL APPROACH: Cox models assessed the risk of progressive CKD. Models adjusted for baseline age, sex, body mass index, hypertension, diabetes, eGFR, proteinuria, and tumor volume. Nonparametric Spearman's correlations were used to examine the association of the number and size of the cysts with clinical characteristics, kidney function, and kidney volumes. RESULTS: There were 1,195 patients with 50 progressive CKD events over a median 4.4 years of follow-up evaluation. On baseline imaging, 38% had at least 1 cyst, 34% had at least 1 cortical cyst, and 8.7% had at least 1 medullary cyst. A higher number of cysts was associated with progressive CKD and was modestly correlated with larger nephrons and more nephrosclerosis on kidney histology. The number of medullary cysts was more strongly associated with progressive CKD than the number of cortical cysts. LIMITATIONS: Patients who undergo a radical nephrectomy may differ from the general population. A radical nephrectomy may accelerate the risk of progressive CKD. Genetic testing was not performed. CONCLUSIONS: Cysts in the kidney, particularly the medulla, should be further examined as a potentially useful imaging biomarker of progressive CKD beyond the current clinical evaluation of kidney function and common CKD risk factors. PLAIN-LANGUAGE SUMMARY: Kidney cysts are common and often are considered of limited clinical relevance despite being associated with lower glomerular filtration rate. We studied a large cohort of patients who had a kidney removed due to a tumor to determine whether cysts in the retained kidney were associated with kidney health in the future. We found that more cysts in the kidney and, in particular, cysts in the deepest tissue of the kidney (the medulla) were associated with progressive kidney disease, including kidney failure where dialysis or a kidney transplantation is needed. Patients with cysts in the kidney medulla may benefit from closer monitoring.


Assuntos
Progressão da Doença , Taxa de Filtração Glomerular , Doenças Renais Císticas , Nefrectomia , Insuficiência Renal Crônica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etiologia , Doenças Renais Císticas/diagnóstico por imagem , Doenças Renais Císticas/patologia , Doenças Renais Císticas/cirurgia , Doenças Renais Císticas/etiologia , Idoso , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Estudos de Coortes , Imageamento por Ressonância Magnética , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
New Phytol ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39149848

RESUMO

Stomatal closure during drought inhibits carbon uptake and may reduce a tree's defensive capacity. Limited carbon availability during drought may increase a tree's mortality risk, particularly if drought constrains trees' capacity to rapidly produce defenses during biotic attack. We parameterized a new model of conifer defense using physiological data on carbon reserves and chemical defenses before and after a simulated bark beetle attack in mature Pinus edulis under experimental drought. Attack was simulated using inoculations with a consistent bluestain fungus (Ophiostoma sp.) of Ips confusus, the main bark beetle colonizing this tree, to induce a defensive response. Trees with more carbon reserves produced more defenses but measured phloem carbon reserves only accounted for c. 23% of the induced defensive response. Our model predicted universal mortality if local reserves alone supported defense production, suggesting substantial remobilization and transport of stored resin or carbon reserves to the inoculation site. Our results show that de novo terpene synthesis represents only a fraction of the total measured phloem terpenes in P. edulis following fungal inoculation. Without direct attribution of phloem terpene concentrations to available carbon, many studies may be overestimating the scale and importance of de novo terpene synthesis in a tree's induced defense response.

8.
Nature ; 561(7722): 211-215, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30135588

RESUMO

In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum1,2. The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now know governs the world at the atomic scale. Since then, studies involving the Lyman-α line-the 1S-2P transition at a wavelength of 121.6 nanometres-have played an important part in physics and astronomy, as one of the most fundamental atomic transitions in the Universe. For example, this transition has long been used by astronomers studying the intergalactic medium and testing cosmological models via the so-called 'Lyman-α forest'3 of absorption lines at different redshifts. Here we report the observation of the Lyman-α transition in the antihydrogen atom, the antimatter counterpart of hydrogen. Using narrow-line-width, nanosecond-pulsed laser radiation, the 1S-2P transition was excited in magnetically trapped antihydrogen. The transition frequency at a field of 1.033 tesla was determined to be 2,466,051.7 ± 0.12 gigahertz (1σ uncertainty) and agrees with the prediction for hydrogen to a precision of 5 × 10-8. Comparisons of the properties of antihydrogen with those of its well-studied matter equivalent allow precision tests of fundamental symmetries between matter and antimatter. Alongside the ground-state hyperfine4,5 and 1S-2S transitions6,7 recently observed in antihydrogen, the Lyman-α transition will permit laser cooling of antihydrogen8,9, thus providing a cold and dense sample of anti-atoms for precision spectroscopy and gravity measurements10. In addition to the observation of this fundamental transition, this work represents both a decisive technological step towards laser cooling of antihydrogen, and the extension of antimatter spectroscopy to quantum states possessing orbital angular momentum.

9.
Nature ; 557(7703): 71-75, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29618820

RESUMO

In 1928, Dirac published an equation 1 that combined quantum mechanics and special relativity. Negative-energy solutions to this equation, rather than being unphysical as initially thought, represented a class of hitherto unobserved and unimagined particles-antimatter. The existence of particles of antimatter was confirmed with the discovery of the positron 2 (or anti-electron) by Anderson in 1932, but it is still unknown why matter, rather than antimatter, survived after the Big Bang. As a result, experimental studies of antimatter3-7, including tests of fundamental symmetries such as charge-parity and charge-parity-time, and searches for evidence of primordial antimatter, such as antihelium nuclei, have high priority in contemporary physics research. The fundamental role of the hydrogen atom in the evolution of the Universe and in the historical development of our understanding of quantum physics makes its antimatter counterpart-the antihydrogen atom-of particular interest. Current standard-model physics requires that hydrogen and antihydrogen have the same energy levels and spectral lines. The laser-driven 1S-2S transition was recently observed 8 in antihydrogen. Here we characterize one of the hyperfine components of this transition using magnetically trapped atoms of antihydrogen and compare it to model calculations for hydrogen in our apparatus. We find that the shape of the spectral line agrees very well with that expected for hydrogen and that the resonance frequency agrees with that in hydrogen to about 5 kilohertz out of 2.5 × 1015 hertz. This is consistent with charge-parity-time invariance at a relative precision of 2 × 10-12-two orders of magnitude more precise than the previous determination 8 -corresponding to an absolute energy sensitivity of 2 × 10-20 GeV.

10.
J Am Soc Nephrol ; 34(7): 1264-1278, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36958059

RESUMO

SIGNIFICANCE STATEMENT: Nephron number currently can be estimated only from glomerular density on a kidney biopsy combined with cortical volume from kidney imaging. Because of measurement biases, refinement of this approach and validation across different patient populations have been needed. The prognostic importance of nephron number also has been unclear. The authors present an improved method of estimating nephron number that corrects for several biases, resulting in a 27% higher nephron number estimate for donor kidneys compared with a prior method. After accounting for comorbidities, the new nephron number estimate does not differ between kidney donors and kidney patients with tumor and shows consistent associations with clinical characteristics across these two populations. The findings also indicate that low nephron number predicts CKD independent of biopsy and clinical characteristics in both populations. BACKGROUND: Nephron number can be estimated from glomerular density and cortical volume. However, because of measurement biases, this approach needs refinement, comparison between disparate populations, and evaluation as a predictor of CKD outcomes. METHODS: We studied 3020 living kidney donors and 1354 patients who underwent radical nephrectomy for tumor. We determined cortex volume of the retained kidney from presurgical imaging and glomerular density by morphometric analysis of needle core biopsy of the donated kidney and wedge sections of the removed kidney. Glomerular density was corrected for missing glomerular tufts, absence of the kidney capsule, and then tissue shrinkage on the basis of analysis of 30 autopsy kidneys. We used logistic regression (in donors) and Cox proportional hazard models (in patients with tumor) to assess the risk of CKD outcomes associated with nephron number. RESULTS: Donors had 1.17 million nephrons per kidney; patients with tumor had 0.99 million nephrons per kidney. A lower nephron number was associated with older age, female sex, shorter height, hypertension, family history of ESKD, lower GFR, and proteinuria. After adjusting for these characteristics, nephron number did not differ between donors and patients with tumor. Low nephron number (defined by <5th or <10th percentile by age and sex in a healthy subset) in both populations predicted future risk of CKD outcomes independent of biopsy and clinical characteristics. CONCLUSIONS: Compared with an older method for estimating nephron number, a new method that addresses several sources of bias results in nephron number estimates that are 27% higher in donors and 1% higher in patients with tumor and shows consistency between two populations. Low nephron number independently predicts CKD in both populations.


Assuntos
Hipertensão , Insuficiência Renal Crônica , Humanos , Feminino , Néfrons/patologia , Rim/patologia , Glomérulos Renais , Hipertensão/patologia , Taxa de Filtração Glomerular
11.
J Am Soc Nephrol ; 34(9): 1535-1545, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37430426

RESUMO

SIGNIFICANCE STATEMENT: Glomerular size differs by cortex depth. Larger nephrons are prognostic of progressive kidney disease, but it is unknown whether this risk differs by cortex depth or by glomeruli versus proximal or distal tubule size. We studied the average minor axis diameter in oval proximal and distal tubules separately and by cortex depth in patients who had radical nephrectomy to remove a tumor from 2019 to 2020. In adjusted analyses, larger glomerular volume in the middle and deep cortex predicted progressive kidney disease. Wider proximal tubular diameter did not predict progressive kidney disease independent of glomerular volume. Wider distal tubular diameter showed a gradient of strength of prediction of progressive kidney disease in the more superficial cortex than in the deep cortex. BACKGROUND: Larger nephrons are prognostic of progressive kidney disease, but whether this risk differs by nephron segments or by depth in the cortex is unclear. METHODS: We studied patients who underwent radical nephrectomy for a tumor between 2000 and 2019. Large wedge kidney sections were scanned into digital images. We estimated the diameters of proximal and distal tubules by the minor axis of oval tubular profiles and estimated glomerular volume with the Weibel-Gomez stereological model. Analyses were performed separately in the superficial, middle, and deep cortex. Cox proportional hazard models assessed the risk of progressive CKD (dialysis, kidney transplantation, sustained eGFR <10 ml/min per 1.73 m 2 , or a sustained 40% decline from the postnephrectomy baseline eGFR) with glomerular volume or tubule diameters. At each cortical depth, models were unadjusted, adjusted for glomerular volume or tubular diameter, and further adjusted for clinical characteristics (age, sex, body mass index, hypertension, diabetes, postnephrectomy baseline eGFR, and proteinuria). RESULTS: Among 1367 patients were 62 progressive CKD events during a median follow-up of 4.5 years. Glomerular volume predicted CKD outcomes at all depths, but only in the middle and deep cortex after adjusted analyses. Proximal tubular diameter also predicted progressive CKD at any depth but not after adjusted analyses. Distal tubular diameter showed a gradient of more strongly predicting progressive CKD in the superficial than deep cortex, even in adjusted analysis. CONCLUSIONS: Larger glomeruli are independent predictors of progressive CKD in the deeper cortex, whereas in the superficial cortex, wider distal tubular diameters are an independent predictor of progressive CKD.


Assuntos
Neoplasias Renais , Insuficiência Renal Crônica , Humanos , Taxa de Filtração Glomerular , Glomérulos Renais/patologia , Nefrectomia/efeitos adversos , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia
12.
J Am Soc Nephrol ; 34(8): 1421-1432, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37254246

RESUMO

SIGNIFICANCE STATEMENT: Nephrosclerosis (glomerulosclerosis, interstitial fibrosis, and tubular atrophy) is the defining pathology of both kidney aging and CKD. Optimal thresholds for nephrosclerosis that identify persons with a progressive disease are unknown. This study determined a young-age threshold (18-29 years) and age-based 95th percentile thresholds for nephrosclerosis on the basis of morphometry of kidney biopsy sections from normotensive living kidney donors. These thresholds were 7.1-fold to 36-fold higher in older (70 years or older) versus younger (aged 18-29 years) normotensive donors. Age-based thresholds, but not young-age threshold, were prognostic for determining risk of progressive CKD among patients who underwent a radical nephrectomy or a for-cause native kidney biopsy, suggesting that age-based thresholds are more useful than a single young-age threshold for identifying CKD on biopsy. BACKGROUND: Nephrosclerosis, defined by globally sclerotic glomeruli (GSG) and interstitial fibrosis and tubular atrophy (IFTA), is a pathology of both kidney aging and CKD. A comparison of risk of progressive CKD using aged-based thresholds for nephrosclerosis versus a single young-adult threshold is needed. METHODS: We conducted morphometric analyses of kidney biopsy images for %GSG, %IFTA, and IFTA foci density among 3020 living kidney donors, 1363 patients with kidney tumor, and 314 patients with native kidney disease. Using normotensive donors, we defined young-age thresholds (18-29 years) and age-based (roughly by decade) 95th percentile thresholds. We compared age-adjusted risk of progressive CKD (kidney failure or 40% decline in eGFR) between nephrosclerosis that was "normal compared with young," "normal for age but abnormal compared with young," and "abnormal for age" in patients with tumor and patients with kidney disease. RESULTS: The 95th percentiles in the youngest group (18-29 years) to the oldest group (70 years or older) ranged from 1.7% to 16% for %GSG, 0.18% to 6.5% for %IFTA, and 8.2 to 59.3 per cm 2 for IFTA foci density. Risk of progressive CKD did not differ between persons with nephrosclerosis "normal compared with young" versus "normal for age but abnormal compared with young." Risk of progressive CKD was significantly higher with %GSG, %IFTA, or IFTA foci density that was abnormal versus normal for age in both cohorts. CONCLUSIONS: Given that increased risk of progressive CKD occurs only when nephrosclerosis is abnormal for age, age-based thresholds for nephrosclerosis seem to be better than a single young-age threshold for identifying clinically relevant CKD.


Assuntos
Nefroesclerose , Insuficiência Renal Crônica , Adulto , Humanos , Idoso , Nefroesclerose/patologia , Prognóstico , Rim/patologia , Nefrectomia , Biópsia , Insuficiência Renal Crônica/patologia , Fibrose , Atrofia/patologia
13.
J Urol ; 209(3): 525-531, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36445045

RESUMO

PURPOSE: Our objective was to examine whether perioperative blood transfusion is associated with venous thromboembolism following radical cystectomy adjusting for both patient- and disease-related factors. MATERIALS AND METHODS: Patients who underwent radical cystectomy for bladder cancer from 1980-2020 were identified in the Mayo Clinic cystectomy registry. Blood transfusion during the initial postoperative hospitalization was analyzed as a 3-tiered variable: no transfusion, postoperative transfusion alone, or intraoperative with or without postoperative transfusion. The primary outcome was venous thromboembolism within 90 days of radical cystectomy. Associations between clinicopathological variables and 90-day venous thromboembolism were assessed using multivariable logistic regression, with transfusion analyzed as both a categorical and a continuous variable. RESULTS: A total of 3,755 radical cystectomy patients were identified, of whom 162 (4.3%) experienced a venous thromboembolism within 90 days of radical cystectomy. Overall, 2,112 patients (56%) received a median of 1 (IQR: 0-3) unit of blood transfusion, including 811 (38%) with intraoperative transfusion only, 572 (27%) with postoperative transfusion only, and 729 (35%) with intraoperative and postoperative transfusion. On multivariable analysis, intraoperative with or without postoperative blood transfusion was associated with a significantly increased risk of venous thromboembolism (adjusted OR 1.73, 95% CI 1.17-2.56, P = .002). Moreover, when analyzed as a continuous variable, each unit of blood transfused intraoperatively was associated with 7% higher odds of venous thromboembolism (adjusted OR 1.07, 95% CI 1.01-1.13, P = .03). CONCLUSIONS: Intraoperative blood transfusion was significantly associated with venous thromboembolism within 90 days of radical cystectomy. To ensure optimal perioperative outcomes, continued effort to limit blood transfusion in radical cystectomy patients is warranted.


Assuntos
Neoplasias da Bexiga Urinária , Tromboembolia Venosa , Humanos , Cistectomia/efeitos adversos , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Transfusão de Sangue , Neoplasias da Bexiga Urinária/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
14.
J Urol ; 209(1): 89-98, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36067373

RESUMO

PURPOSE: The KEYNOTE-564 trial demonstrated that adjuvant pembrolizumab after nephrectomy for clear cell renal cell carcinoma decreased the risk of disease progression and potentially overall mortality as well. Herein, we used a Markov model to weigh the costs, toxicities, and efficacy of pembrolizumab to further investigate its utility. MATERIALS AND METHODS: Decision-analytic Markov modeling was used to conduct a cost-utility analysis of adjuvant pembrolizumab versus observation after nephrectomy for high-risk clear cell renal cell carcinoma, using data from KEYNOTE-564 to inform model probabilities. Primary outcomes were quality-adjusted life years, Medicare costs, and incremental cost-effectiveness ratios. The willingness-to-pay threshold utilized was $100,000/quality-adjusted life year. RESULTS: At 5 years, adjuvant treatment with pembrolizumab resulted in 0.3 additional quality-adjusted life years at an additional cost of $99,484 relative to observation. Pembrolizumab was found not to be cost-effective at a 5-year time horizon (incremental cost-effectiveness ratio=$326,534). On sensitivity analysis, pembrolizumab became cost-effective if its per cycle cost was <$5,064 (base=$10,278) or its 5-year progression benefit was >18.8% (base 9%). Upon simulation, pembrolizumab was cost-effective for 29% of patients at 5 years. Specifically, we found that pembrolizumab would be cost-effective at 5 years for patients with at least a 59% 5 year risk of progression, which corresponds to a Mayo Progression-free Survival Score ≥10. CONCLUSIONS: At current prices, adjuvant pembrolizumab was found to be cost-effective only for the highest risk subset of clear cell renal cell carcinoma patients 5 years after treatment, including patients with complete metastasectomy, regional lymph node involvement, or ≥7cm pT3 tumors with sarcomatoid features. Longer-term trial data, including overall survival results, are necessary to confirm these extrapolations.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Idoso , Estados Unidos , Humanos , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/cirurgia , Análise Custo-Benefício , Seleção de Pacientes , Medicare , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/cirurgia
15.
J Urol ; 210(4): 611-618, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37338930

RESUMO

PURPOSE: Multiple prognostic models exist to assess survival among patients with metastatic clear cell renal cell carcinoma. However, the relative contribution of histopathological features of the metastasis has not been extensively studied. Herein, we compared models using clinical, primary tumor, and metastatic features to predict cancer-specific survival for patients with surgically resected metastatic clear cell renal cell carcinoma. MATERIALS AND METHODS: We studied 266 patients who had undergone nephrectomy between 1970 and 2019, and who had a single site of metastasis completely resected. Two versions of the metastatic clear cell renal cell carcinoma score published by Leibovich et al were calculated, using grade and necrosis from the primary tumor and using grade and necrosis from the metastasis. Predictive abilities of these 2 versions and a third model that included metastatic features only were compared using c-indexes from Cox proportional hazards models. RESULTS: A total of 197 patients died from renal cell carcinoma at a median of 2.3 years (IQR 1.1-4.5); median follow-up among survivors was 13.2 years (IQR 10.0-14.5). The Leibovich score using grade and necrosis from the metastasis (c=0.679) had similar predictive ability compared to the original Leibovich score using grade and necrosis from the primary tumor (c=0.675). A third model (c=0.707) demonstrated that metastasectomy within 2 years after nephrectomy, presence of bone metastasis, high grade, and sarcomatoid differentiation in the metastasis were significantly associated with cancer-specific survival. CONCLUSIONS: Scoring algorithms calculated using histopathological features of the metastasis can be used to predict cancer-specific survival for patients with surgically resected metastatic clear cell renal cell carcinoma. These findings are of particular importance for instances when primary tumor histopathology is not readily available.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Prognóstico , Nefrectomia , Necrose , Estudos Retrospectivos
16.
New Phytol ; 237(4): 1154-1163, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36052762

RESUMO

Disruption of photosynthesis and carbon transport due to damage to the tree crown and stem cambial cells, respectively, can cause tree mortality. It has recently been proposed that fire-induced dysfunction of xylem plays an important role in tree mortality. Here, we simultaneously tested the impact of a lethal fire dose on nonstructural carbohydrates (NSCs) and xylem hydraulics in Pinus ponderosa saplings. Saplings were burned with a known lethal fire dose. Nonstructural carbohydrates were assessed in needles, main stems, roots and whole plants, and xylem hydraulic conductivity was measured in the main stems up to 29 d postfire. Photosynthesis and whole plant NSCs declined postfire. Additionally, all burned saplings showed 100% phloem/cambium necrosis, and roots of burned saplings had reduced NSCs compared to unburned and defoliated saplings. We further show that, contrary to patterns observed with NSCs, water transport was unchanged by fire and there was no evidence of xylem deformation in saplings that experienced a lethal dose of heat from fire. We conclude that phloem and cambium mortality, and not hydraulic failure, were probably the causes of death in these saplings. These findings advance our understanding of the physiological response to fire-induced injuries in conifer trees.


Assuntos
Fome , Sede , Floema , Carboidratos , Xilema/fisiologia , Árvores/fisiologia , Água , Caules de Planta
17.
New Phytol ; 240(1): 92-104, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430467

RESUMO

Shifts in the age or turnover time of non-structural carbohydrates (NSC) may underlie changes in tree growth under long-term increases in drought stress associated with climate change. But NSC responses to drought are challenging to quantify, due in part to large NSC stores in trees and subsequently long response times of NSC to climate variation. We measured NSC age (Δ14 C) along with a suite of ecophysiological metrics in Pinus edulis trees experiencing either extreme short-term drought (-90% ambient precipitation plot, 2020-2021) or a decade of severe drought (-45% plot, 2010-2021). We tested the hypothesis that carbon starvation - consumption exceeding synthesis and storage - increases the age of sapwood NSC. One year of extreme drought had no impact on NSC pool size or age, despite significant reductions in predawn water potential, photosynthetic rates/capacity, and twig and needle growth. By contrast, long-term drought halved the age of the sapwood NSC pool, coupled with reductions in sapwood starch concentrations (-75%), basal area increment (-39%), and bole respiration rates (-28%). Our results suggest carbon starvation takes time, as tree carbon reserves appear resilient to extreme disturbance in the short term. However, after a decade of drought, trees apparently consumed old stored NSC to support metabolism.


Assuntos
Carbono , Pinus , Carbono/metabolismo , Pinus/fisiologia , Secas , Carboidratos/química , Amido/metabolismo , Árvores/fisiologia , Metabolismo dos Carboidratos
18.
J Theor Biol ; 562: 111417, 2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-36682408

RESUMO

Mathematical models are increasingly used throughout infectious disease outbreaks to guide control measures. In this review article, we focus on the initial stages of an outbreak, when a pathogen has just been observed in a new location (e.g., a town, region or country). We provide a beginner's guide to two methods for estimating the risk that introduced cases lead to sustained local transmission (i.e., the probability of a major outbreak), as opposed to the outbreak fading out with only a small number of cases. We discuss how these simple methods can be extended for epidemiological models with any level of complexity, facilitating their wider use, and describe how estimates of the probability of a major outbreak can be used to guide pathogen surveillance and control strategies. We also give an overview of previous applications of these approaches. This guide is intended to help quantitative researchers develop their own epidemiological models and use them to estimate the risks associated with pathogens arriving in new host populations. The development of these models is crucial for future outbreak preparedness. This manuscript was submitted as part of a theme issue on "Modelling COVID-19 and Preparedness for Future Pandemics".


Assuntos
COVID-19 , Humanos , Surtos de Doenças/prevenção & controle , Modelos Teóricos , Pandemias
19.
Helicobacter ; 28(3): e12968, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37025012

RESUMO

BACKGROUND: Recent data on the prevalence of H. pylori infection in Jamaica are lacking. It is postulated that there has been a decline in the prevalence of H. pylori infection and its associated complications. We determined sociodemographic characteristics, prevalence of H. pylori infection and clinical outcomes among adults undergoing esophagogastroduodenoscopy (EGD) and histology at the University Hospital of the West Indies (UHWI) between May 2018 and December 2020. MATERIALS AND METHODS: A cross-sectional study of patients (≥18 years old), who underwent EGD and histological evaluation for H. pylori infection, was conducted. Associations of H. pylori positivity and gastric cancer with sociodemographic/clinical variables and endoscopic findings were determined by stepwise logistic regression using backward selection. Unadjusted and adjusted odds ratios with related 95% confidence intervals (Cis) were calculated for H. pylori positivity and gastric cancer status. RESULTS: There were 323 participants (mean age 58.6 ± 17.8 years, 54.2% females). H. pylori prevalence was 22.2% (n = 70 of 315), 5.6% had gastric neoplasia (GN), 15.5% gastric atrophy, 11.4% intestinal metaplasia and 3.7% dysplasia on histology. Mucositis (64.5%), gastric ulcer (14.9%), and duodenal ulcer (13.9%) were the most common endoscopic findings. Participants with peptic ulcer disease (PUD) (unOR = 4.0; p = .017), gastric cancer (unOR = 9.5; p = .003), gastric atrophy (unOR = 12.8; p < .001), and intestinal metaplasia (unOR = 5.0; p < .001) had a significantly higher odds of being H. pylori positive, but after multivariable analyses only gastric atrophy remained significant (aOR = 27.3; p < .001). Participants with mucositis had a significantly lower odds of gastric cancer (unOR 0.1; p = .035) while participants with dysplasia had significantly higher odds (unOR 8.0; p = .042), but these were no longer significant after multivariable analyses (aOR = 0.2; p = .156 and aOR = 18.9; p = .070, respectively). CONCLUSIONS: Histology based prevalence of H. pylori infection is lower than previously reported in Jamaica. Gastric atrophy is a significant predictor of H. pylori positivity.


Assuntos
Gastrite Atrófica , Infecções por Helicobacter , Helicobacter pylori , Mucosite , Neoplasias Gástricas , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Adolescente , Masculino , Estudos Transversais , Jamaica/epidemiologia , Neoplasias Gástricas/patologia , Mucosite/complicações , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/patologia , Endoscopia Gastrointestinal , Gastrite Atrófica/complicações , Atrofia , Hospitais de Ensino , Metaplasia/complicações , Prevalência
20.
Int J Mol Sci ; 24(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36835448

RESUMO

Many chronic inflammatory conditions are mediated by an increase in the number of monocytes in peripheral circulation, differentiation of monocytes to macrophages, and different macrophage subpopulations during pro- and anti-inflammatory stages of tissue injury. When hepcidin secretion is stimulated during inflammation, the iron export protein ferroportin is targeted for degradation on a limited number of cell types, including monocytes and macrophages. Such changes in monocyte iron metabolism raise the possibility of non-invasively tracking the activity of these immune cells using magnetic resonance imaging (MRI). We hypothesized that hepcidin-mediated changes in monocyte iron regulation influence both cellular iron content and MRI relaxation rates. In response to varying conditions of extracellular iron supplementation, ferroportin protein levels in human THP-1 monocytes decreased two- to eightfold, consistent with paracrine/autocrine regulation of iron export. Following hepcidin treatment, ferroportin protein levels further decreased two- to fourfold. This was accompanied by an approximately twofold increase in total transverse relaxation rate, R2*, compared to non-supplemented cells. A positive correlation between total cellular iron content and R2* improved from moderate to strong in the presence of hepcidin. These findings suggest that hepcidin-mediated changes detected in monocytes using MRI could be valuable for in vivo cell tracking of inflammatory responses.


Assuntos
Hepcidinas , Inflamação , Ferro , Monócitos , Humanos , Hepcidinas/metabolismo , Ferro/metabolismo , Macrófagos/metabolismo , Imageamento por Ressonância Magnética , Monócitos/metabolismo , Inflamação/metabolismo
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