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1.
J Surg Res ; 280: 196-203, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35994981

RESUMO

INTRODUCTION: Beta-blockers (BB) after traumatic brain injury (TBI) accelerate cognitive recovery weeks after injury. BBs also inhibit leukocyte (LEU) mobilization to the penumbral blood brain barrier (BBB) 48-h after TBI. It is unclear whether the latter effects persist longer and accompany the persistent cognitive improvement. We hypothesized that 2 wk of BB after TBI reduce penumbral BBB leukocyte-endothelial interactions. METHODS: Thirty CD1 mice underwent TBI (controlled cortical impact, CCI: 6 m/s velocity, 1 mm depth, 3 mm diameter) or sham craniotomy followed by i.p. saline (NS) or propranolol (1, 2, 4 mg/kg) every 12 h for 14 d. On day 14, in vivo pial intravital microscopy visualized endothelial-LEU interactions and BBB microvascular leakage. Day 14 Garcia neurological test scores and animal weights were compared to preinjury levels reflecting concurrent clinical recovery. RESULTS: LEU rolling was greatest in CCI + NS when compared to sham (P = 0.03). 4 mg/kg propranolol significantly reduced postCCI LEU rolling down to uninjured sham levels (P = 0.03). LEU adhesion and microvascular permeability were not impacted at this time interval. Untreated injured animals (CCI + NS) scored lower Garcia neurological test and greater weight loss recovery at day 14 when compared to preinjury (P < 0.05). Treatment with higher doses of propranolol (2, 4 mg/kg), improved weight loss recovery (P < 0.001). CONCLUSIONS: LEU rolling alone, was influenced by BB therapy 14 d after TBI suggesting that certain penumbral neuroinflammatory cellular effects of BB therapy after TBI persist up to 2 wk after injury potentially explaining the pervasive beneficial effects of BBs on learning and memory.


Assuntos
Edema Encefálico , Lesões Encefálicas Traumáticas , Animais , Camundongos , Barreira Hematoencefálica , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Modelos Animais de Doenças , Leucócitos , Propranolol/farmacologia , Propranolol/uso terapêutico , Redução de Peso
2.
J Trauma Acute Care Surg ; 92(5): 781-791, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35045056

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is accompanied by a hyperadrenergic catecholamine state that can cause penumbral neuroinflammation. Prospective human studies demonstrate improved TBI survival with beta blockade (bb), although mechanisms remain unclear. We hypothesized that deranged post-TBI penumbral blood brain barrier (BBB) leukocyte mobilization and permeability are improved by bb. METHODS: CD1 male mice (n = 64) were randomly assigned to severe TBI-controlled cortical impact: 6 m/s velocity, 1 mm depth, 3 mm diameter-or sham craniotomy, and IP injection of either saline or propranolol (1, 2, or 4 mg/kg) every 12 hours for 2 days. At 48 hours, in vivo pial intravital microscopy visualized live endothelial-leukocyte (LEU) interactions and BBB microvascular leakage. Twice daily clinical recovery was assessed by regaining of lost body weight and the Garcia Neurological Test (motor, sensory, reflex, balance assessments). Brain edema was determined by hemispheric wet-to-dry ratios. RESULTS: Propranolol after TBI reduced both in vivo LEU rolling and BBB permeability in a dose-dependent fashion compared with no treatment (p < 0.001). Propranolol reduced cerebral edema (p < 0.001) and hastened recovery of lost body weight at 48 hours (p < 0.01). Compared with no treatment (14.9 ± 0.2), 24-hour Garcia Neurologic Test scores were improved with 2 (15.8 ± 0.2, p = 0.02) and 4 (16.1 ± 0.1, p = 0.001) but not with 1 mg/kg propranolol. CONCLUSION: Propranolol administration reduces post-TBI LEU mobilization and microvascular permeability in the murine penumbral neurovasculature and leads to reduced cerebral edema. This is associated with hastened recovery of post-TBI weight loss and neurologic function with bb treatment. Dose-dependent effects frame a mechanistic relationship between bb and improved human outcomes after TBI.


Assuntos
Edema Encefálico , Lesões Encefálicas Traumáticas , Encefalopatia Traumática Crônica , Animais , Feminino , Masculino , Camundongos , Barreira Hematoencefálica , Peso Corporal , Edema Encefálico/etiologia , Edema Encefálico/prevenção & controle , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/tratamento farmacológico , Modelos Animais de Doenças , Leucócitos , Permeabilidade , Propranolol/farmacologia , Propranolol/uso terapêutico , Estudos Prospectivos
3.
Front Artif Intell ; 4: 636234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33748748

RESUMO

Soil moisture (SM) plays a significant role in determining the probability of flooding in a given area. Currently, SM is most commonly modeled using physically-based numerical hydrologic models. Modeling the natural processes that take place in the soil is difficult and requires assumptions. Besides, hydrologic model runtime is highly impacted by the extent and resolution of the study domain. In this study, we propose a data-driven modeling approach using Deep Learning (DL) models. There are different types of DL algorithms that serve different purposes. For example, the Convolutional Neural Network (CNN) algorithm is well suited for capturing and learning spatial patterns, while the Long Short-Term Memory (LSTM) algorithm is designed to utilize time-series information and to learn from past observations. A DL algorithm that combines the capabilities of CNN and LSTM called ConvLSTM was recently developed. In this study, we investigate the applicability of the ConvLSTM algorithm in predicting SM in a study area located in south Louisiana in the United States. This study reveals that ConvLSTM significantly outperformed CNN in predicting SM. We tested the performance of ConvLSTM based models by using a combination of different sets of predictors and different LSTM sequence lengths. The study results show that ConvLSTM models can predict SM with a mean areal Root Mean Squared Error (RMSE) of 2.5% and mean areal correlation coefficients of 0.9 for our study area. ConvLSTM models can also provide predictions between discrete SM observations, making them potentially useful for applications such as filling observational gaps between satellite overpasses.

4.
J Trauma Acute Care Surg ; 91(1): 108-113, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33605694

RESUMO

BACKGROUND: Neuroinflammation and cerebral edema development following severe traumatic brain injury (TBI) affect subsequent cognitive recovery. Independent of its anticoagulant effects, antithrombin III (AT-III) has been shown to block neurovascular inflammation after severe TBI, reduce cerebral endothelial-leukocyte interactions, and decrease blood-brain barrier permeability. We hypothesized that AT-III administration after TBI would improve post-TBI cognitive recovery, specifically enhancing learning, and memory. METHODS: Fifteen CD1 male mice were randomized to undergo severe TBI (controlled cortical impact [CCI]: velocity, 6 m/s; depth, 1 mm; diameter, 3 mm) or sham craniotomy and received either intravenous AT-III (250 IU/kg) or vehicle (VEH/saline) 15 minutes and 24 hours post-TBI. Animals underwent Morris water maze testing from 6 to 14 days postinjury consisting of cued learning trials (platform visible), spatial learning trials (platform invisible, spatial cues present), and probe (memory) trials (platform removed, spatial cues present). Intergroup differences were assessed by the Kruskal-Wallis test (p < 0.05). RESULTS: Morris water maze testing demonstrated that cumulative cued learning (overall mean time in seconds to reach the platform on days 6-8) was worst in CCI-VEH animals (26.1 ± 2.4 seconds) compared with CCI-AT-III counterparts (20.3 ± 2.1 seconds, p < 0.01). Cumulative noncued spatial learning was also worst in the CCI-VEH group (23.4 ± 1.8 seconds) but improved with AT-III (17.6 ± 1.5 seconds, p < 0.01). In probe trials, AT-III failed to significantly improve memory ability. Animals that underwent sham craniotomy demonstrated preserved learning and memory compared with all CCI counterparts (p < 0.05). CONCLUSION: Antithrombin III improves neurocognitive recovery weeks after TBI. This improvement is particularly related to improvement in learning but not memory function. Pharmacologic support of enhanced learning may support new skill acquisition or relearning to improve outcomes after TBI. LEVEL OF EVIDENCE: Therapeutic/care management, level II.


Assuntos
Antitrombina III/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Encefalopatia Traumática Crônica/tratamento farmacológico , Cognição/efeitos dos fármacos , Teste do Labirinto Aquático de Morris/efeitos dos fármacos , Animais , Encefalopatia Traumática Crônica/sangue , Sinais (Psicologia) , Modelos Animais de Doenças , Masculino , Camundongos , Distribuição Aleatória
5.
J Trauma Acute Care Surg ; 90(2): 274-280, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33093292

RESUMO

BACKGROUND: Acute traumatic coagulopathy often accompanies traumatic brain injury (TBI) and may impair cognitive recovery. Antithrombin III (AT-III) reduces the hypercoagulability of TBI. Antithrombin III and heparinoids such as enoxaparin (ENX) demonstrate potent anti-inflammatory activity, reducing organ injury and modulating leukocyte (LEU) activation, independent of their anticoagulant effect. It is unknown what impact AT-III exerts on cerebral LEU activation and blood-brain barrier (BBB) permeability after TBI. We hypothesized that AT-III reduces live microcirculatory LEU-endothelial cell (EC) interactions and leakage at the BBB following TBI. METHODS: CD1 mice (n = 71) underwent either severe TBI (controlled cortical impact (CCI), 6-m/s velocity, 1-mm depth, and 4-mm diameter) or sham craniotomy and then received either AT-III (250 IU/kg), ENX (1.5 mg/kg), or vehicle (saline) every 24 hours. Forty-eight hours post-TBI, cerebral intravital microscopy visualized in vivo penumbral microvascular LEU-EC interactions and microvascular leakage to assess BBB inflammation/permeability. Body weight loss and the Garcia neurological test (motor, sensory, reflex, balance) served as surrogates of clinical recovery. RESULTS: Both AT-III and ENX similarly reduced in vivo penumbral LEU rolling and adhesion (p < 0.05). Antithrombin III also reduced live BBB leakage (p < 0.05). Antithrombin III animals demonstrated the least 48-hour body weight loss (8.4 ± 1%) versus controlled cortical impact and vehicle (11.4 ± 0.5%, p < 0.01). Garcia neurological test scores were similar among groups. CONCLUSION: Antithrombin III reduces post-TBI penumbral LEU-EC interactions in the BBB leading to reduced neuromicrovascular permeability. Antithrombin III further reduced body weight loss compared with no therapy. Further study is needed to determine if these AT-III effects on neuroinflammation affect longer-term neurocognitive recovery after TBI.


Assuntos
Antitrombina III/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Hemorragia Encefálica Traumática/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Animais , Hemorragia Encefálica Traumática/sangue , Ensaios de Migração de Leucócitos , Modelos Animais de Doenças , Enoxaparina/farmacologia , Migração e Rolagem de Leucócitos/efeitos dos fármacos , Masculino , Camundongos
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