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1.
BMC Cancer ; 24(1): 677, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38831291

RESUMO

BACKGROUND: Mortality benefit of transfusion with leucoreduced whole blood has not been demonstrated in the sub-Saharan Africa (SSA). We compared mortality in patients with cancer transfused with leucoreduced and non-leucoreduced whole blood in a SSA setting. METHODS: An open-label randomized controlled trial was conducted at the Uganda Cancer Institute where participants were randomized in a 1:1 ratio into the leucoreduced and non-leucoreduced whole blood transfusion arms. Leucocyte filtration of whole blood was performed within 72 h of blood collection. Patients aged ≥ 15 years who were prescribed blood transfusion by the primary physicians were eligible for study enrolment. Mortality difference was analyzed using intention-to-treat survival analysis and cox proportional hazard model was used to analyze factors associated with mortality. RESULTS: There were 137 participants randomized to the leucoreduced and 140 to the non-leucoreduced arms. Baseline characteristics were similar between the two arms. The median number of blood transfusions received was 1 (IQR, 1-3) unit and 2 (IQR, 1-3) units in the leucoreduced and non-leucoreduced arms respectively, p = 0.07. The 30-day mortality rate in the leucoreduced arm was 4.6% (95% CI, 2.1-10) and was 6.2% (95% CI, 3.2-12.1) in the non-leucoreduced arm (p = 0.57), representing an absolute effect size of only 1.6%. Increasing age (HR = 0.92, 95% CI, 0.86-0.98, p = 0.02) and Eastern Co-operative Oncology Group (ECOG) performance score of 1 (HR = 0.03, 95% CI, 0.00-0.31, p < 0.01) were associated with reduced 30-day mortality. CONCLUSIONS: The study failed to demonstrate mortality difference between cancer patients transfused with leucoreduced and non-leucoreduced whole blood. Although this study does not support nor refute universal leucoreduction to reduce mortality in patients with cancer in SSA, it demonstrates the feasibility of doing transfusion RCTs in Uganda, where a multi-center trial with an appropriate sample size is needed. TRIAL REGISTRATION: Pan African Clinical Trial Registry, https://pactr.samrc.ac.za/ (PACTR202302787440132). Registered on 06/02/2023.


Assuntos
Transfusão de Sangue , Neoplasias , Humanos , Masculino , Feminino , Uganda/epidemiologia , Pessoa de Meia-Idade , Neoplasias/mortalidade , Neoplasias/terapia , Transfusão de Sangue/métodos , Transfusão de Sangue/estatística & dados numéricos , Adulto , Idoso , Procedimentos de Redução de Leucócitos/métodos , Modelos de Riscos Proporcionais
2.
Neuroendocrinology ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39191217

RESUMO

INTRODUCTION: The purpose of this study was to evaluate longitudinal changes in Ki-67 indices of SI-NETs and assess the impact of these in overall survival (OS). METHODS: We screened 551 patients with SI-NETs diagnosed from 1993, through 2021, identified using the SI-NET databases from five European referral centres. Only patients with well-differentiated tumours and available baseline tumour samples, and follow-up re-biopsies were included. For tumour grading, apart from 2017 WHO classification system, we applied a recently proposed SI-NET site-specific modified histopathological grading system with Ki-67 cut-offs of 5 and 10%. RESULTS: We included 45 patients. Median Ki-67 index at SI-NET diagnosis was 2% (range 0.5-15%). Thirty-three patients had Ki67 indices <5% (70.2%), 6 had Ki67: 5-10% (12.8%) and 8 had Ki67 ≥10% (17%). Mean time to re-biopsy was 48.8 months (SD: +/-162.5). At re-biopsy, the median change in Ki-67 index (absolute value; follow-up minus time of diagnosis) was 1% (range -10 to +38%). An increase in Ki-67 occurred in 20 patients (42.6%); in 14 patients the change in Ki-67 resulted in progression to higher tumour grade following the modified grading system. Patients with an increment in Ki-67≥1% had a median OS of 32.9 months vs. 80.5 months in patients without (HR 5.6, 95% CI: 1.42-22.02, p=0.014). When applying the novel modified histopathological grading system for SI-NETs, patients with grade progression had a median OS of 32.9 months vs. 53.7 months in those without (HR=4.61, 95%CI: 1.22-13.54; p=0.022). At multivariable analysis, grade progression was confirmed as an independent predictor for death (HR=7.2, 95%CI: 1.58-32.82; p=0.011). CONCLUSIONS: Metachronous increment in Ki-67 indices and related grade progression over time following a site-specific modified histopathological grading system with Ki-67 cut-offs of 5 and 10% is observed in approximately 1/3 of SI-NETs included in this study and it is associated with worse survival outcomes.

3.
Nature ; 563(7732): 514-521, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30356216

RESUMO

During both embryonic development and adult tissue regeneration, changes in chromatin structure driven by master transcription factors lead to stimulus-responsive transcriptional programs. A thorough understanding of how stem cells in the skeleton interpret mechanical stimuli and enact regeneration would shed light on how forces are transduced to the nucleus in regenerative processes. Here we develop a genetically dissectible mouse model of mandibular distraction osteogenesis-which is a process that is used in humans to correct an undersized lower jaw that involves surgically separating the jaw bone, which elicits new bone growth in the gap. We use this model to show that regions of newly formed bone are clonally derived from stem cells that reside in the skeleton. Using chromatin and transcriptional profiling, we show that these stem-cell populations gain activity within the focal adhesion kinase (FAK) signalling pathway, and that inhibiting FAK abolishes new bone formation. Mechanotransduction via FAK in skeletal stem cells during distraction activates a gene-regulatory program and retrotransposons that are normally active in primitive neural crest cells, from which skeletal stem cells arise during development. This reversion to a developmental state underlies the robust tissue growth that facilitates stem-cell-based regeneration of adult skeletal tissue.


Assuntos
Regeneração Óssea , Mandíbula/citologia , Mandíbula/fisiologia , Crista Neural/citologia , Osteogênese por Distração , Células-Tronco/citologia , Animais , Cromatina/genética , Cromatina/metabolismo , Modelos Animais de Doenças , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Regulação da Expressão Gênica , Masculino , Mandíbula/cirurgia , Camundongos , Camundongos Endogâmicos C57BL , Retroelementos/genética , Transdução de Sinais , Células-Tronco/metabolismo , Transcrição Gênica
4.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34620713

RESUMO

In the skin, tissue injury results in fibrosis in the form of scars composed of dense extracellular matrix deposited by fibroblasts. The therapeutic goal of regenerative wound healing has remained elusive, in part because principles of fibroblast programming and adaptive response to injury remain incompletely understood. Here, we present a multimodal -omics platform for the comprehensive study of cell populations in complex tissue, which has allowed us to characterize the cells involved in wound healing across both time and space. We employ a stented wound model that recapitulates human tissue repair kinetics and multiple Rainbow transgenic lines to precisely track fibroblast fate during the physiologic response to skin injury. Through integrated analysis of single cell chromatin landscapes and gene expression states, coupled with spatial transcriptomic profiling, we are able to impute fibroblast epigenomes with temporospatial resolution. This has allowed us to reveal potential mechanisms controlling fibroblast fate during migration, proliferation, and differentiation following skin injury, and thereby reexamine the canonical phases of wound healing. These findings have broad implications for the study of tissue repair in complex organ systems.


Assuntos
Cicatriz/patologia , Fibroblastos/metabolismo , Fibrose/patologia , Pele/lesões , Cicatrização/fisiologia , Animais , Diferenciação Celular , Movimento Celular , Proliferação de Células , Matriz Extracelular/metabolismo , Feminino , Mecanotransdução Celular/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Pele/metabolismo
5.
Phys Rev Lett ; 130(19): 199902, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243665

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.117.235303.

6.
J Neuroeng Rehabil ; 20(1): 169, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38115144

RESUMO

BACKGROUND: Currently, there is little available in-depth analysis of the biomechanical effect of different prostheses on the musculoskeletal system function and residual limb internal loading for persons with bilateral transfemoral/through-knee amputations (BTF). Commercially available prostheses for BTF include full-length articulated prostheses (microprocessor-controlled prosthetic knees with dynamic response prosthetic feet) and foreshortened non-articulated stubby prostheses. This study aims to assess and compare the BTF musculoskeletal function and loading during gait with these two types of prostheses. METHODS: Gait data were collected from four male traumatic military BTF and four able-bodied (AB) matched controls using a 10-camera motion capture system with two force plates. BTF completed level-ground walking trials with full-length articulated and foreshortened non-articulated stubby prostheses. Inverse kinematics, inverse dynamics and musculoskeletal modelling simulations were conducted. RESULTS: Full-length articulated prostheses introduced larger stride length (by 0.5 m) and walking speed (by 0.3 m/s) than stubbies. BTF with articulated prostheses showed larger peak hip extension angles (by 10.1°), flexion moment (by 1.0 Nm/kg) and second peak hip contact force (by 3.8 bodyweight) than stubbies. There was no difference in the hip joint loading profile between BTF with stubbies and AB for one gait cycle. Full-length articulated prostheses introduced higher hip flexor muscle force impulse than stubbies. CONCLUSIONS: Compared to stubbies, BTF with full-length articulated prostheses can achieve similar activity levels to persons without limb loss, but this may introduce detrimental muscle and hip joint loading, which may lead to reduced muscular endurance and joint degeneration. This study provides beneficial guidance in making informed decisions for prosthesis choice.


Assuntos
Amputados , Membros Artificiais , Humanos , Masculino , Amputação Cirúrgica , Marcha/fisiologia , Caminhada/fisiologia , Articulação do Joelho/fisiologia , Articulação do Quadril , Músculos , Fenômenos Biomecânicos
7.
J Environ Manage ; 328: 117005, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36508983

RESUMO

Potential new sources of phosphorus (P) fertilizer are the recovered P from livestock wastewater through chemical precipitation and the ash from combusting animal manures. Although most of the research on P losses from conservation tillage include high water-soluble P compounds from commercial fertilizer sources, information on the use of non-conventional, low water-soluble, recycled P sources is scarce. Particularly for sandy soils of the United States (US) Southeastern Coastal Plain region, research driven information on P loss into the environment is needed to determine recommendations for a direct use of new recycled P sources as crop P fertilizers. The objective of this study is to investigate the potential P runoff from sandy soils under conservation tillage, fertilized with recovered P from liquid swine manure and turkey litter ash in comparison with commercial P fertilizer triple superphosphate (TSP). The field study included two typical sandy soils of the US Southeastern Coastal Plain region, the Noboco and Norfolk. Simulated rain corresponding to the annual 30-min rainfall in the study site (Florence County, South Carolina) was applied to plots treated with recovered P from liquid swine manure, turkey litter ash, and TSP, including a control with no P added. The runoff was monitored and sampled every 5 min during the test and composite soil samples were collected from the top (0-15 cm) and subsurface (15-30 cm) soil layers in each plot. Laboratory analyses were conducted to quantify both total P (TP) and soluble reactive P (SRP) in runoff samples, and the soil test P in the soil layers. Two-way analyses of variances show significant treatment effects on both TP and SRP runoff. The quantities of SRP runoff from plots treated with the recovered P from swine manure and turkey litter ash represent respectively 1% and 7-8% of SRP runoff from plots treated with TSP. Hence, the use of the recovered P materials as crop P fertilizers through surface broadcast application present less environmental risks compared to commercial TSP.


Assuntos
Fósforo , Solo , Animais , Suínos , Fósforo/análise , Fosfatos , Fertilizantes/análise , Areia , Esterco , Movimentos da Água , Chuva , Agricultura
8.
9.
Ann Surg ; 273(1): 173-180, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30829705

RESUMO

OBJECTIVE: The aim of this study was to determine the interaction of full thickness excisional wounds and tumors in vivo. SUMMARY OF BACKGROUND DATA: Tumors have been described as wounds that do not heal due to similarities in stromal composition. On the basis of observations of slowed tumor growth after ulceration, we hypothesized that full thickness excisional wounds would inhibit tumor progression in vivo. METHODS: To determine the interaction of tumors and wounds, we developed a tumor xenograft/allograft (human head and neck squamous cell carcinoma SAS/mouse breast carcinoma 4T1) wound mouse model. We examined tumor growth with varying temporospatial placement of tumors and wounds or ischemic flap. In addition, we developed a tumor/wound parabiosis model to understand the ability of tumors and wounds to recruit circulating progenitor cells. RESULTS: Tumor growth inhibition by full thickness excisional wounds was dose-dependent, maintained by sequential wounding, and relative to distance. This effect was recapitulated by placement of an ischemic flap directly adjacent to a xenograft tumor. Using a parabiosis model, we demonstrated that a healing wound was able to recruit significantly more circulating progenitor cells than a growing tumor. Tumor inhibition by wound was unaffected by presence of an immune response in an immunocompetent model using a mammary carcinoma. Utilizing functional proteomics, we identified 100 proteins differentially expressed in tumors and wounds. CONCLUSION: Full thickness excisional wounds have the ability to inhibit tumor growth in vivo. Further research may provide an exact mechanism for this remarkable finding and new advances in wound healing and tumor biology.


Assuntos
Neoplasias/patologia , Úlcera/patologia , Ferimentos e Lesões/patologia , Animais , Feminino , Camundongos , Neoplasias/complicações , Úlcera/complicações , Ferimentos e Lesões/complicações
14.
Ann Surg ; 272(1): 183-193, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-30585822

RESUMO

OBJECTIVE: To investigate the effects of local doxycycline administration on skin scarring. BACKGROUND: Skin scarring represents a major source of morbidity for surgical patients. Doxycycline, a tetracycline antibiotic with off-target effects on the extracellular matrix, has demonstrated antifibrotic effects in multiple organs. However, doxycycline's potential effects on skin scarring have not been explored in vivo. METHODS: Female C57BL/6J mice underwent dorsal wounding following an established splinted excisional skin wounding model. Doxycycline was administered by local injection into the wound base following injury. Wounds were harvested upon complete wound closure (postoperative day 15) for histological examination and biomechanical testing of scar tissue. RESULTS: A one-time dose of 3.90 mM doxycycline (2 mg/mL) within 12 hours of injury was found to significantly reduce scar thickness by 24.8% (P < 0.0001) without compromising tensile strength. The same effect could not be achieved by oral dosing. In doxycycline-treated scar matrices, collagen I content was significantly reduced (P = 0.0317) and fibers were favorably arranged with significantly increased fiber randomness (P = 0.0115). Common culprits of altered wound healing mechanics, including angiogenesis and inflammation, were not impacted by doxycycline treatment. However, engrailed1 profibrotic fibroblasts, responsible for scar extracellular matrix deposition, were significantly reduced with doxycycline treatment (P = 0.0005). CONCLUSIONS: Due to the substantial improvement in skin scarring and well-established clinical safety profile, locally administered doxycycline represents a promising vulnerary agent. As such, we favor rapid translation to human patients as an antiscarring therapy.


Assuntos
Cicatriz/prevenção & controle , Colágeno/efeitos dos fármacos , Doxiciclina/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Doxiciclina/administração & dosagem , Feminino , Injeções Intralesionais , Camundongos , Camundongos Endogâmicos C57BL , Resistência à Tração
17.
N Engl J Med ; 387(9): 833-838, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36053509
19.
BMC Cancer ; 20(1): 798, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32831073

RESUMO

BACKGROUND: The optimal chemotherapy regimen for treating HIV associated NHL in low resource settings is unknown. We conducted a retrospective study to describe survival rates, treatment response rates and adverse events in patients with HIV associated NHL treated with CHOP and dose adjusted-EPOCH regimens at the Uganda Cancer Institute. METHODS: A retrospective study of patients diagnosed with HIV and lymphoma and treated at the Uganda Cancer Institute from 2016 to 2018 was done. RESULTS: One hundred eight patients treated with CHOP and 12 patients treated with DA-EPOCH were analysed. Patients completing 6 or more cycles of chemotherapy were 51 (47%) in the CHOP group and 8 (67%) in the DA-EPOCH group. One year overall survival (OS) rate in patients treated with CHOP was 54.5% (95% CI, 42.8-64.8) and 80.2% (95% CI, 40.3-94.8) in those treated with DA-EPOCH. Factors associated with favourable survival were BMI 18.5-24.9 kg/m2, (p = 0.03) and completion of 6 or more cycles of chemotherapy, (p < 0.001). The overall response rate was 40% in the CHOP group and 59% in the DA-EPOCH group. Severe adverse events occurred in 19 (18%) patients in the CHOP group and 3 (25%) in the DA-EPOCH group; these were neutropenia (CHOP = 13, 12%; DA-EPOCH = 2, 17%), anaemia (CHOP = 12, 12%; DA-EPOCH = 1, 8%), thrombocytopenia (CHOP = 7, 6%; DA-EPOCH = 0), sepsis (CHOP = 1), treatment related death (DA-EPOCH = 1) and hepatic encephalopathy (CHOP = 1). CONCLUSION: Treatment of HIV associated NHL with curative intent using CHOP and infusional DA-EPOCH is feasible in low resource settings and associated with > 50% 1 year survival.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Infecções por HIV/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Adulto , Anemia/induzido quimicamente , Anemia/economia , Anemia/epidemiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Ciclofosfamida/economia , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Doxorrubicina/economia , Esquema de Medicação , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Etoposídeo/economia , Feminino , Infecções por HIV/imunologia , Encefalopatia Hepática/induzido quimicamente , Encefalopatia Hepática/economia , Encefalopatia Hepática/epidemiologia , Humanos , Infusões Intravenosas/economia , Infusões Intravenosas/métodos , Linfoma Difuso de Grandes Células B/economia , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Neutropenia/economia , Neutropenia/epidemiologia , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prednisona/economia , Estudos Retrospectivos , Sepse/induzido quimicamente , Sepse/economia , Sepse/epidemiologia , Taxa de Sobrevida , Trombocitopenia/induzido quimicamente , Trombocitopenia/economia , Trombocitopenia/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Uganda/epidemiologia , Vincristina/administração & dosagem , Vincristina/efeitos adversos , Vincristina/economia
20.
Scand J Med Sci Sports ; 28(4): 1461-1466, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29283451

RESUMO

Research has shown that high levels of stress and stress responsivity can increase the risk of injuries. However, most of the research that has supported this notion has focused on between-person relationships, ignoring the relationships at the within-person level. As a result, the objective of this study was to investigate if within-person changes in perceived stress symptoms over a 1-month time period could predict injury rates during the subsequent 3 months. A prospective design with two measurement points (Time 1-at the beginning of the season and Time 2-1 month into the season) was utilized. A total of 121 competitive soccer players (85 males and 36 females; Mage  = 18.39, SD = 3.08) from Sweden and the United States completed the Kessler Psychological Distress Scale (KPDS) and a demographic sheet at Time 1. The KPDS was also completed at Time 2, and all acute injuries that occurred during the subsequent 3-month period were recorded. A Bayesian latent change scores model was used to determine whether within-person changes in stress symptoms could predict the risk of injury. Results revealed that there was a credible positive effect of changes in stress symptoms on injury rates, indicating that an increase in reported stress symptoms was related to an increased risk for injury. This finding highlights the importance of creating caring and supportive sporting environments and relationships and teaching stress management techniques, especially during the earlier portion of competitive seasons, to possibly reduce the occurrence of injuries.


Assuntos
Traumatismos em Atletas/epidemiologia , Futebol/lesões , Estresse Psicológico/epidemiologia , Adolescente , Teorema de Bayes , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco , Suécia , Estados Unidos , Adulto Jovem
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