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1.
Int J Mol Sci ; 22(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208374

RESUMO

Previous studies have demonstrated that pioglitazone, a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, inhibits ischemia-induced brain injury. The present study was conducted to examine whether pioglitazone can reduce impairment of behavioral deficits mediated by inflammatory-induced brain white matter injury in neonatal rats. Intraperitoneal (i.p.) injection of lipopolysaccharide (LPS, 2 mg/kg) was administered to Sprague-Dawley rat pups on postnatal day 5 (P5), and i.p. administration of pioglitazone (20 mg/kg) or vehicle was performed 5 min after LPS injection. Sensorimotor behavioral tests were performed 24 h after LPS exposure, and changes in biochemistry of the brain was examined after these tests. The results show that systemic LPS exposure resulted in impaired sensorimotor behavioral performance, reduction of oligodendrocytes and mitochondrial activity, and increases in lipid peroxidation and brain inflammation, as indicated by the increment of interleukin-1ß (IL-1ß) levels and number of activated microglia in the neonatal rat brain. Pioglitazone treatment significantly improved LPS-induced neurobehavioral and physiological disturbances including the loss of body weight, hypothermia, righting reflex, wire-hanging maneuver, negative geotaxis, and hind-limb suspension in neonatal rats. The neuroprotective effect of pioglitazone against the loss of oligodendrocytes and mitochondrial activity was associated with attenuation of LPS-induced increment of thiobarbituric acid reactive substances (TBARS) content, IL-1ß levels and number of activated microglia in neonatal rats. Our results show that pioglitazone prevents neurobehavioral disturbances induced by systemic LPS exposure in neonatal rats, and its neuroprotective effects are associated with its impact on microglial activation, IL-1ß induction, lipid peroxidation, oligodendrocyte production and mitochondrial activity.


Assuntos
Comportamento Animal , Encefalite/tratamento farmacológico , Mitocôndrias/patologia , Pioglitazona/uso terapêutico , Substância Branca/patologia , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Citocinas/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Encefalite/patologia , Feminino , Hipotermia Induzida , Lipopolissacarídeos , Microglia/efeitos dos fármacos , Microglia/patologia , Mitocôndrias/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/patologia , Pioglitazona/farmacologia , Gravidez , Ratos Sprague-Dawley , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Redução de Peso/efeitos dos fármacos , Substância Branca/efeitos dos fármacos
2.
Neurochem Int ; 176: 105743, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641026

RESUMO

Neonatal brain inflammation produced by intraperitoneal (i.p.) injection of lipopolysaccharide (LPS) results in long-lasting brain dopaminergic injury and motor disturbances in adult rats. The goal of the present work is to investigate the effect of neonatal systemic LPS exposure (1 or 2 mg/kg, i.p. injection in postnatal day 5, P5, male rats)-induced dopaminergic injury to examine methamphetamine (METH)-induced behavioral sensitization as an indicator of drug addiction. On P70, subjects underwent a treatment schedule of 5 once daily subcutaneous (s.c.) administrations of METH (0.5 mg/kg) (P70-P74) to induce behavioral sensitization. Ninety-six hours following the 5th treatment of METH (P78), the rats received one dose of 0.5 mg/kg METH (s.c.) to reintroduce behavioral sensitization. Hyperlocomotion is a critical index caused by drug abuse, and METH administration has been shown to produce remarkable locomotor-enhancing effects. Therefore, a random forest model was used as the detector to extract the feature interaction patterns among the collected high-dimensional locomotor data. Our approaches identified neonatal systemic LPS exposure dose and METH-treated dates as features significantly associated with METH-induced behavioral sensitization, reinstated behavioral sensitization, and perinatal inflammation in this experimental model of drug addiction. Overall, the analysis suggests that the implementation of machine learning strategies is sensitive enough to detect interaction patterns in locomotor activity. Neonatal LPS exposure also enhanced METH-induced reduction of dopamine transporter expression and [3H]dopamine uptake, reduced mitochondrial complex I activity, and elevated interleukin-1ß and cyclooxygenase-2 concentrations in the P78 rat striatum. These results indicate that neonatal systemic LPS exposure produces a persistent dopaminergic lesion leading to a long-lasting change in the brain reward system as indicated by the enhanced METH-induced behavioral sensitization and reinstated behavioral sensitization later in life. These findings indicate that early-life brain inflammation may enhance susceptibility to drug addiction development later in life, which provides new insights for developing potential therapeutic treatments for drug addiction.


Assuntos
Animais Recém-Nascidos , Lipopolissacarídeos , Aprendizado de Máquina , Metanfetamina , Animais , Metanfetamina/farmacologia , Metanfetamina/toxicidade , Ratos , Masculino , Lipopolissacarídeos/toxicidade , Comportamento Animal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Encefalite/induzido quimicamente , Encefalite/metabolismo , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/induzido quimicamente , Doenças Neuroinflamatórias/metabolismo , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Feminino , Ratos Sprague-Dawley , Atividade Motora/efeitos dos fármacos
3.
Adv Healthc Mater ; 12(8): e2202477, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36507565

RESUMO

Critical-sized cranial bone defects fail to re-ossify and require the surgical intervention of cranioplasty. To achieve superior bone healing in such cases, a hydrogel consisting of an interpenetrating network of collagen and elastin-like polypeptide to encapsulate bone morphogenetic protein-2 (BMP-2), doxycycline, and 45S5 Bioglass is developed. This hydrogel has an appropriate elastic modulus of 39 ± 2.2 kPa to allow proper handling during implantation. The hydrogel promotes human adipose-derived stem attachment, proliferation, and differentiation toward the osteogenic lineage, including the deposition of hydroxyapatite particles embedded within a collagenous fibrillar structure after 21 days of in vitro culture. After eight weeks of implantation of the acellular hydrogel in a critical-sized rat cranial defect model, only a small quantity of various pro-inflammatory (< 20 pg mg-1 ) and anti-inflammatory (< 10 pg mg-1 ) factors in the adjacent cranial tissue is noticed, indicating the overall biocompatibility of the hydrogel. Scanning electron microscopy evidenced the presence of new fibrous extracellular matrix and mineral aggregates at the defect site, with calcium/phosphorus ratio of 0.5 and 2.0 by eight and twelve weeks, respectively. Microcomputed tomography (Micro-CT) and histological analyses showed formation of mature mineralized tissue that bridged with the surrounding bone. Taken together, the acellular composite hydrogel shows great promise for superior bone healing after cranioplasty.


Assuntos
Elastina , Hidrogéis , Ratos , Humanos , Animais , Hidrogéis/farmacologia , Hidrogéis/química , Elastina/farmacologia , Elastina/química , Microtomografia por Raio-X , Regeneração Óssea , Osteogênese , Peptídeos , Colágeno/farmacologia , Colágeno/química , Crânio/diagnóstico por imagem , Proteína Morfogenética Óssea 2/farmacologia , Diferenciação Celular
4.
Cureus ; 13(9): e18016, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34667691

RESUMO

Background In the USA, spinal fusion surgery incurs the highest hospital cost. Despite the recent advances in the application of enhanced recovery after surgery (ERAS) protocols in these surgeries, the efficacy of these protocols in improving the perioperative outcomes remains unclear. We conducted a retrospective review as a quality improvement (QI) project to analyze the efficacy of the ERAS protocol with intraoperative modified thoracolumbar interfascial plane (mTLIP) block to determine whether these interventions reduce the length of stay (LOS) and opioid requirements during the postoperative period. Methods Retrospective reviews of adult patients (>18 yrs) who underwent elective lumbar spinal fusion or laminectomy at our institute were reviewed. Patients were administered oral gabapentin and acetaminophen preoperatively. Prior to incision, an mTLIP block was performed using liposomal bupivacaine. Intraoperatively, ketamine, ketorolac, and tranexamic acid were administered. Postoperative, pain control was treated with scheduled acetaminophen, ketorolac, and low-dose ketamine infusion. Hydromorphone and oxycodone were administered for breakthrough pain. Patients who underwent a similar procedure without ERAS protocol were chosen as controls to assess the efficacy of ERAS protocol. Data pertaining to patient demographics, operative and perioperative use of analgesics, LOS, 90-day readmissions, and morbidity were collected. Patients who underwent laminectomy and spinal fusion surgery were analyzed separately Results A total of 65 patients were identified; laminectomy (n- 24), spinal fusion surgery (n-41). In the laminectomy patients, treatment group (n-12) and the control group (n-12). Treatment group receiving the ERAS protocol with the regional anesthesia via the mTLIP (n= 12) opioid requirement was reduced by 51.42% [P = 0.03], and LOS was reduced by 2.04 days [P = 0.01] [0.75 days vs. 2.79 days]). In the spinal fusion patients, treatment group (n-15) and control group (n-26). Treatment group receiving the ERAS protocol with the use of regional anesthesia via the mTLIP group (n= 15), opioid requirement was reduced by 38.33% [P = 0.04]. No difference in LOS was observed at 5.4 days vs. 4.88 days (P = 0.28). Conclusion ERAS protocol in patients undergoing lumbar spinal surgery incorporated the use of regional anesthesia via the mTLIP block, we observed there is a statistically significant reduction in the LOS for lumbar laminectomy and a significant reduction in opioid administration for lumbar laminectomies and spinal fusion surgery.

5.
Cureus ; 13(11): e19558, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34917438

RESUMO

Background Opioid sparing anesthesia and enhanced recovery after surgery protocols are not innovative ideas. However, the utilization of pancreaticoduodenectomy is limited. With the rise in awareness of the opioid epidemic in the United States, we have created a multimodal approach to anesthesia and postoperative care to limit adverse effects of opioids and curb the use of opioids postoperatively. Methods We conducted a retrospective cohort study performed by chart review of an opioid-sparing anesthetic and enhanced recovery after surgery (ERAS) protocol initiated jointly by the anesthesiology departments and transplant surgery for pancreaticoduodenectomy from January 2017 to October 2019. Results Demographic data was found to be comparable between the control and protocol groups. Hospital length of stay, ICU length of stay, and opioid requirements significantly decreased in the protocol group. Hospital length of stay decreased from 8.92 to 5.72 days, ICU days decreased from 1.52 to 0.42 days, and narcotics for the first five hospital days were significantly decreased from 130.13 to 71.2 morphine milligram equivalents. Conclusion Proper postoperative pain management can improve patient satisfaction and decrease complication rates. Pancreaticoduodenectomy is a complicated procedure with relatively limited data regarding enhanced recovery after surgery protocols. Likewise, there is limited data regarding opioid-sparing anesthesia techniques. Our protocol produced promising hospital length of stay and reduced opioid administration during the first five hospital days without increasing 30-day readmission rates.

6.
Ann Card Anaesth ; 24(1): 42-46, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33938830

RESUMO

Study Objective: The aim of this study is to see if there are any clinical differences between using 35 F DLT for all patients versus using patient height regardless of gender to estimate appropriate DLT size. Design: Prospective randomized study. Setting: University Hospital. Patients: 50 patients age ≤18 years, undergoing lung or esophageal surgery requiring OLV. Interventions: Patients randomized to two groups (group-35F, group -DLT based on height). Measurements and Main Results: Data collected include demographics, ASA status, airway assessment, number of intubation attempts, Cormack-Lehane grade, number of times DLT repositioned, incidence of sore throat, oxygen saturation at induction and oxygen saturation at 5 minutes and 10 minutes after OLV. There was no statistically significant difference in demographics, ASA classification, Mallampati score, number of intubation attempts, Cormack-Lehane grade, number of times DLT was repositioned, and incidence of sore throat. In height based DLT group the odds were higher for the incidence of sore throat in 37-41 F group. Oxygen saturation at induction, 5 minutes and 10 minutes after OLV are not statistically significant between the two groups. Conclusion: Our findings suggest that the majority of patients receive unnecessarily large DLTs for thoracic surgery, which not only makes intubation inherently more difficult but also increases their risk of postoperative sore throat.


Assuntos
Cirurgia Torácica , Procedimentos Cirúrgicos Torácicos , Adolescente , Humanos , Incidência , Intubação Intratraqueal , Estudos Prospectivos
7.
Neurotrauma Rep ; 2(1): 270-284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34223557

RESUMO

Nearly all persons with spinal cord injury (SCI) will develop osteoporosis following injury, and further, up to 50% of all persons with SCI will sustain a fracture during their lives. The unique mechanisms driving osteoporosis following SCI remain unknown. The cannabinoid system modulation of bone metabolism through cannabinoid 1/2 (CB1/2) has been of increasing interest for the preservation of bone mass and density in models of osteoporosis. Using a thoracic vertebral level 8 (T8) complete transection in a mouse model, we performed daily treatment with a selective CB2 receptor agonist, HU308, compared with SCI-vehicle-treated and naïve control animals either immediately after injury for 40 days, or in a delayed paradigm, following 3 months after injury. The goal was to prevent or potentially reverse SCI-induced osteoporosis. In the acute phase, administration of the CB2 agonist was not able to preserve the rapid loss of cancellous bone. In the delayed-treatment paradigm, in cortical bone, HU308 increased cortical-area to total-area ratio and periosteal perimeter in the femur, and improved bone density in the distal femur and proximal tibia. Further, we report changes to the metaphyseal periosteum with increased presence of adipocyte and fat mass in the periosteum of SCI animals, which was not present in naïve animals. The layer of fat increased markedly in HU308-treated animals compared with SCI-vehicle-treated animals. Overall, these data show that CB2 agonism targets a number of cell types that can influence overall bone quality.

8.
J Neuroimmunol ; 343: 577226, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247229

RESUMO

Spinal cord injury (SCI) results in perturbations to the immune system leading to increased infection susceptibility. In parallel, the consumption of high-fat diets (HFD) leads to a chronic inflammation in circulation and body tissues. We investigated the impact of 16 weeks of HFD on chronically-injured rats. SCI rats under both chow and HFD showed peripheral leukocyte changes that include reduced percentages of total, helper and cytotoxic T, and natural killer cells. Expression of immune-related genes in the spleen and thymus reflected the impact of both chronic injury and diet. Changes to the immune system following SCI are adversely impacted by HFD consumption.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Traumatismos da Medula Espinal/imunologia , Baço/imunologia , Linfócitos T/imunologia , Timo/imunologia , Animais , Masculino , Ratos , Ratos Long-Evans , Traumatismos da Medula Espinal/sangue , Transcriptoma/imunologia
9.
Adv Healthc Mater ; 9(4): e1901385, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31985174

RESUMO

The goals of this study are to evaluate the ability of the multicomponent collagen-elastin-like polypeptide (ELP)-Bioglass scaffolds to support osteogenesis of rat mesenchymal stem cells (rMSCs), demonstrate in vivo biocompatibility by subcutaneous implantation in Sprague-Dawley rats, monitor degradation noninvasively, and finally assess the scaffold's ability in healing critical-sized cranial bone defects. The collagen-ELP-Bioglass scaffold supports the in vitro osteogenic differentiation of rMSCs over a 3 week culture period. The cellular (rMSC-containing) or acellular scaffolds implanted in the subcutaneous pockets of rats do not cause any local or systemic toxic effects or tumors. The real-time monitoring of the fluorescently labeled scaffolds by IVIS reveals that the scaffolds remain at the site of implantation for up to three weeks, during which they degrade gradually. Micro-CT analysis shows that the bilateral cranial critical-sized defects created in rats lead to greater bone regeneration when filled with cellular scaffolds. Bone mineral density and bone microarchitectural parameters are comparable among different scaffold groups, but the histological analysis reveals increased formation of high-quality mature bone in the cellular group, while the acellular group has immature bone and organized connective tissue. These results suggest that the rMSC-seeded collagen-ELP-Bioglass composite scaffolds can aid in better bone healing process.


Assuntos
Elastina , Osteogênese , Animais , Regeneração Óssea , Diferenciação Celular , Cerâmica , Colágeno , Peptídeos , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual , Alicerces Teciduais
10.
Neurochem Int ; 135: 104686, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31987865

RESUMO

Perinatal inflammation-induced reduction in pain threshold may alter pain sensitivity to hyperalgesia or allodynia which may persist into adulthood. In this study, we investigated the anti-inflammatory protective effect of interleukin-1 receptor antagonist (IL-1ra), an anti-inflammatory cytokine, on systemic lipopolysaccharide (LPS)-induced spinal cord inflammation and oxidative stress, thermal hyperalgesia, and mechanical allodynia in neonatal rats. Intraperitoneal (i.p.) injection of LPS (2 mg/kg) or sterile saline was performed in postnatal day 5 (P5) rat pups, and IL-1ra (100 mg/kg) or saline was administered (i.p.) 5 min after LPS injection. Pain reflex behavior, spinal cord inflammation and oxidative stress were examined 24 h after LPS administration. Systemic LPS exposure led to a reduction of tactile threshold in the von Frey filament tests (mechanical allodynia) and pain response latency in the tail-flick test (thermal hyperalgesia) of P6 neonatal rats. Spinal cord inflammation was indicated by the increased numbers of activated glial cells including microglia (Iba1+) and astrocytes (GFAP+), and elevated levels of pro-inflammatory cytokine interleukin-1ß (IL-1ß), cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2) 24 h after LPS treatment. LPS treatment induced spinal oxidative stress as evidenced by the increase in thiobarbituric acid reactive substances (TBARS) content in the spinal cord. LPS exposure also led to a significant increase in oligodendrocyte lineage population (Olig2+) and mature oligodendrocyte cells (APC+) in the neonatal rat spinal cord. IL-1ra treatment significantly reduced LPS-induced effects including hyperalgesia, allodynia, the increased number of activated microglia, astrocytes and oligodendrocytes, and elevated levels of IL-1ß, COX-2, PGE2, and lipid peroxidation (TBARS) in the neonatal rat spinal cord. These data suggest that IL-1ra provides a protective effect against the development of pain hypersensitivity, spinal cord inflammation and oxidative stress in the neonatal rats following LPS exposure, which may be associated with the blockade of LPS-induced pro-inflammatory cytokine IL-1ß.


Assuntos
Hiperalgesia/tratamento farmacológico , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Lipopolissacarídeos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Receptores de Interleucina-1/antagonistas & inibidores , Medula Espinal/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Feminino , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Proteína Antagonista do Receptor de Interleucina 1/farmacologia , Masculino , Estresse Oxidativo/fisiologia , Medição da Dor/efeitos dos fármacos , Medição da Dor/métodos , Gravidez , Ratos , Ratos Sprague-Dawley , Receptores de Interleucina-1/metabolismo , Medula Espinal/metabolismo
11.
J Spinal Disord Tech ; 22(7): 473-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20075809

RESUMO

STUDY DESIGN: A novel degenerative disc disease model and sustained delivery method for corticosteroid in male Sprague-Dawley albino rats. OBJECTIVES: To develop a model of degenerative disc disease and to determine the effect of continuous sustained release of corticosteroid on the process of degeneration within the traumatized disc. SUMMARY OF BACKGROUND DATA: The current modalities of treating symptomatic degenerative disc disease are either conservative or surgical. However, there is no cure for the degenerative process and prevention, therefore, is the ideal treatment. An understanding of the mechanisms involved in disc degeneration is crucial to develop new methods for prevention and treatment, including appropriate delivery systems and dosages of repair factors. METHODS: The L5-L6 intervertebral disc was pierced with a 23-gauge needle in 18 rats. The animals received either sham or corticosterone-charged tricalcium phosphate ceramic capsules. The rats were euthanized at 4 weeks. Chondrocytes in the transition zone areas were counted and compared statistically. RESULTS: The surgical technique induced degeneration of the nucleus without evidence of inflammation at adjacent levels when compared with nontraumatized controls. The number of chondrocytes per area was significantly less in the sham group than in the control group. Corticosteroid treatment showed chondrocyte numbers similar to control in 4 of 5 different views of the disc. The anterior region of the disc had 50% less chondrocytes per area than the control; however, the chondrocyte numbers were 50% greater than in the same site from discs of sham animals. CONCLUSIONS: The results show the development of a degenerative disc animal model that can be used to test the effects of growth enhancing factors in disc repair. Administration of continuous sustained release of corticosterone can slow the process of degeneration within the traumatized disc in the rat model.


Assuntos
Anti-Inflamatórios/farmacologia , Corticosterona/farmacologia , Degeneração do Disco Intervertebral/tratamento farmacológico , Disco Intervertebral/efeitos dos fármacos , Animais , Anti-Inflamatórios/uso terapêutico , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/uso terapêutico , Contagem de Células , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrócitos/fisiologia , Corticosterona/uso terapêutico , Modelos Animais de Doenças , Esquema de Medicação , Fibrocartilagem/citologia , Fibrocartilagem/efeitos dos fármacos , Fibrocartilagem/fisiologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Inflamação/fisiopatologia , Disco Intervertebral/citologia , Disco Intervertebral/fisiologia , Degeneração do Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Regeneração/efeitos dos fármacos , Regeneração/fisiologia , Resultado do Tratamento
13.
Anat Rec A Discov Mol Cell Evol Biol ; 282(2): 147-56, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15627985

RESUMO

The objective of this study was to determine the effects of spaceflight on the structure of the tendon-bone junction (TBJ). Pregnant rats either flew in the space shuttle Atlantis (flight group; F) or were exposed to simulated launch and landing protocols (synchronous control group; SC) during days 9-19 of pregnancy. Following birth of their pups, maternal hindlimbs were studied using scanning electron and light microscopic histomophometric techniques. The tibial and calcaneal tuberosities, the fibular head, and the tibia-fibula junction were studied. Myofiber density and cross-sectional area of the quadratus femoris and soleus muscles and diameters of the calcaneal and patellar tendons were also evaluated. Cortical erosion was significantly greater at the tibial tuberosity and the fibular head in F animals compared to SC animals (P < 0.001). Sharpey fiber density was significantly less at the tibial tuberosity and fibular head in F animals compared to SC animals (P < 0.001). The myofiber area of both the soleus and quadratus femoris muscles and the diameters of both calcaneal and patellar tendons were significantly less in F compared to SC rats (P < 0.05). Our data illustrate that the TBJ morphology is affected by spaceflight at the attachment sites of the soleus and quadratus femoris muscles in pregnant animals, which could adversely affect their physical properties. These atrophic TBJ changes could have resulted from atrophy of the adjacent muscles and their tendons. Atrophic changes in the structure of the TBJ could predispose an animal to injury following spaceflight, when normal gravity conditions are reestablished.


Assuntos
Osso e Ossos/fisiologia , Membro Posterior/fisiologia , Junção Neuromuscular/fisiologia , Voo Espacial , Tendões/fisiologia , Animais , Osso e Ossos/ultraestrutura , Feminino , Junção Neuromuscular/ultraestrutura , Gravidez , Ratos , Ratos Sprague-Dawley , Tendões/ultraestrutura
14.
Biomed Sci Instrum ; 51: 122-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996708

RESUMO

Density variations, due to particle size and time and temperature of sintering, affect the delivery profile of substances from ceramic delivery devices. This investigation was conducted to study the effect of polylactic acid (PLA) impregnation on the porosity of hydroxyapatite (HA) capsules by studying the delivery rate of bovine serum albumin (BSA) and testosterone (TE). HA capsules were fabricated by cold compressing calcined particles at 1000, 3000, and 5000 lbs. Each group was subdivided into PLA-impregnated and non-PLA impregnated capsules. Each capsule was loaded with either 40 mg of TE (impregnated or nonimpregnated with PLA polymer) or BSA. Data obtained in this study suggest that: (1) PLA impregnation of HA ceramic capsules decreases the rate of release of drugs from the ceramic reservoir, (2) Physiochemical characteristics of the drugs to be delivered is an instrumental key in the sustained release profiles, (3) Compression load of HA reservoirs is a key factor in predicting the duration and level of sustained delivery, and (4) Polymer coating of HA ceramic capsules reduces the pore size, as well as, blocking some of the pores on the surface.

15.
Biomed Sci Instrum ; 51: 128-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996709

RESUMO

The needs of dental patients are becoming ever complex. This is largely due to the increasing number of systemic conditions that patients present with during routine or emergency dental visits, such as hypertension and angina pectoris. Medications that patients are prescribed have potential to cause effects on the oral tissues. There is a need to understand the interactions between the oral tissues and materials used to restore teeth. The objective of this study was to assess the physiological function of human gingival fibroblasts upon exposure to dental adhesives; polymethyl methacryate, OptiBond®, and Prime & Bond®; Porphyromonas gingivalis lipopolysaccharide and Cortisol or Nifedipine. An increase in metabolic activity was noted with the experimental group exposed to the combination of Prime & Bond®, LPS-PG, and Nifedipine (P<0.001). Oxidative stress was observed in experimental groups exposed to the combinations of PMMA, LPS-PG, and Cortisol (P<0.001); also noted in all three dental adhesives in combinations with LPS-PG and Nifedipine (P<0.001). Cellular membrane damage was evident in experimental groups exposed to the combinations of PMMA, LPS-PG, and Cortisol; PMMA, LPS-PG, and Nifedipine; and Prime & Bond®, LPS-PG, and Nifedipine. In conclusion, it appears that the addition of Nifedipine in combination with LPS-PG negatively alters cellular function by causing membrane damage and inducing oxidative stress.

16.
Biomed Sci Instrum ; 51: 135-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996710

RESUMO

Demineralized bone matrix protein (DBM) was considered highly effective in stimulating bone healing. The objective of the study was to explore the use of tricalcium phosphate (TCP) delivery system to continuously deliver DBM in an osteoporotic condition and to evaluate changes in bone density and preservation of the spine. Ovariectomized Sprague Dawley rats were divided into three equal groups (n=16 per group). Animals in group I served as control, animals in groups II and III were surgically implanted with either empty (SHAM) or DBM filled TCP implants adjacent to L4/L5. Eight animals from each group were euthanized at 2 and 8 weeks post implantation. Femurs were evaluated for changes in density, and the lumbar spine was evaluated for changes in the endplate. Results of this study revealed (1) TCP implants were capable of delivering DBM for long duration, (2) use of sustained delivery of DBM did not induce untoward effects in the vital organs or in the uterus, fallopian tubes, or vaginal tissues, (3) DBM had no effect on chondrocyte differentiation in the spine, and (4) DBM did not increase bone density in osteoporotic female rats.

17.
Breast Cancer Res ; 5(5): R157-69, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12927047

RESUMO

BACKGROUND: Antimitotic chemotherapeutic agents target tubulin, the major protein in mitotic spindles. Tubulin isotype composition is thought to be both diagnostic of tumor progression and a determinant of the cellular response to chemotherapy. This implies that there is a difference in isotype composition between normal and tumor tissues. METHODS: To determine whether such a difference occurs in breast tissues, total tubulin was fractionated from lysates of paired normal and tumor breast tissues, and the amounts of beta-tubulin classes I + IV, II, and III were measured by competitive enzyme-linked immunosorbent assay (ELISA). Only primary tumor tissues, before chemotherapy, were examined. Her2/neu protein amplification occurs in about 30% of breast tumors and is considered a marker for poor prognosis. To gain insight into whether tubulin isotype levels might be correlated with prognosis, ELISAs were used to quantify Her2/neu protein levels in these tissues. RESULTS: Beta-tubulin isotype distributions in normal and tumor breast tissues were similar. The most abundant beta-tubulin isotypes in these tissues were beta-tubulin classes II and I + IV. Her2/neu levels in tumor tissues were 5-30-fold those in normal tissues, although there was no correlation between the Her2/neu biomarker and tubulin isotype levels. CONCLUSION: These results suggest that tubulin isotype levels, alone or in combination with Her2/neu protein levels, might not be diagnostic of tumorigenesis in breast cancer. However, the presence of a broad distribution of these tubulin isotypes (for example, 40-75% beta-tubulin class II) in breast tissue, in conjunction with other factors, might still be relevant to disease progression and cellular response to antimitotic drugs.


Assuntos
Neoplasias da Mama/química , Mama/química , Tubulina (Proteína)/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Ligação Competitiva , Encéfalo/metabolismo , Neoplasias da Mama/patologia , Ensaio de Imunoadsorção Enzimática/métodos , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Receptor ErbB-2/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Tubulina (Proteína)/biossíntese , Células Tumorais Cultivadas
18.
Biomed Sci Instrum ; 50: 54-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405404

RESUMO

This study investigated the effects of dual delivery of statin and vancomycin on angiogenesis during the healing process of a femoral defect injury using tricalcium phosphate lysine (TCPL) delivery system in an animal model. The experimental design consisted of 14 rats divided into the following three groups: Group I animals (n=5) served as the intact control without treatment. Group II animals (n=5) were subjected to a surgically induced defect (2 mm, midshaft of the right femur) and implanted (IM) with TCPL capsules loaded with vancomycin (20mg) (TCPL-AB). Group III animals (n=4) were operated on in a similar fashion as Group II, and subsequently implanted with TCPL capsules loaded vancomycin (20 mg) plus statin (5 mg). The animals were euthanized at 30 days post-implantation using overdose of isoflourane. The right femurs were then harvested in addition to the vital organs, the reproductive organs, and sample of the adjacent skeletal muscles. The hard and soft tissues were evaluated histopathologically by following laboratory standard techniques. The results of this study indicated that statin plus vancomycin treated animals had increased angiogenetic activities with many blood vessels compared to the sham group and the animals also healed in a greater magnitude than the sham group (independent evaluators (p<0.001)). Histomorphometric analysis demonstrated that exposure to sustained delivery of statin resulted in increased blood vessels. It appeared there is a direct correlation of the increased angiogenesis and the increased bone formation in the statin group and this may be one of the mechanisms with which statin form bone. In conclusion, data obtained from this study demonstrated that sustained delivery of statin by TCPL resulted in a remarkable increase in angiogenic and osteogenic activities during the healing process of a femoral defect.

19.
Biomed Sci Instrum ; 50: 132-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405415

RESUMO

Alzheimer’s disease (AD) is the only cause of death among the top 10 diseases that cannot be prevented, cured, or slowed with the current treatments available. Amyloid beta is thought to be the main initiator of AD cognitive decline, activating internal pathways which lead to inflammation, oxidation, and cell death. The objective of this study was to determine if pretreatment of human SH-SY5Y neuroblastoma cells, a model for AD, with antioxidants thymoquinone (TQ), epigallocatechin-3-gallate (EGCG), or dilinoleoylphosphatidylcholine (DLPC) 30 minutes prior to a challenge with tumor necrosis factor a (TNFa), an inflammatory mediator, can prevent oxidation of amyloid beta (Aß). Following treatment, cells were incubated and groups evaluated at 24, 48, and 72 hours. Human amyloid precursor protein (APP) enzyme-linked immune-sorbent assay (ELISA) and nitric oxide assays were performed from supernatant whereas protein and glutathione assays were performed from cells. When TNFa was added to cells, Aß significantly increased 3-fold compared to untreated cells. The addition of antioxidants EGCG, TQ, and DLPC reduced Aß back toward control value at the initial time point. TNFa also caused a significant increase in nitric oxide without changes in glutathione. TQ administered to the cells prior to a challenge with TNFa resulted in a decrease in nitric oxide and an increase in glutathione which may be a possible mechanism to reduce inflammation and reduce oxidation. Additional studies are needed to determine the signaling pathways implemented in the SH-SY5Y cells following TNFa.

20.
Biomed Sci Instrum ; 50: 361-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25405445

RESUMO

The FaDu squamous cell carcinoma cell line was used to test combination treatments of natural (EgCg and TQ) drugs and a chemotherapeutic (5-FU) drug to determine if combining drugs with different cell cycle targets would be more effective at destroying cancer cells than one drug that only targets one phase of the cell cycle. There were a total of four different combinations. One combination consisted of all three treatments: EgCg, TQ, and 5-FU. The other three combinations were as follows: EgCg + TQ, EgCg + 5-FU, and TQ + 5-FU. The combination treatments were measured at 24, 48, and 72 hours. There were significant reductions in cell number at each time increment. The combination of any two drugs especially a natural drug plus a chemotherapeutic drug proved to be more effective than single individual drugs in eradicating cancer. The combination of EGCG + TQ + 5-FU proved to be most effective in cell reduction. Since a combination of drugs target more than one phase of the cell cycle, the cells were less likely to become resistant to two or more drugs.

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