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Several COVID-19 vaccines, some more efficacious than others, are now available and deployed, including multiple mRNA- and viral vector-based vaccines. With the focus on creating cost-effective solutions that can reach the low- and medium- income world, GreenLight Biosciences has developed an mRNA vaccine candidate, GLB-COV2-043, encoding for the full-length SARS-CoV-2 Wuhan wild-type spike protein. In pre-clinical studies in mice, GLB-COV2-043 induced robust antigen-specific binding and virus-neutralizing antibody responses targeting homologous and heterologous SARS-CoV-2 variants and a TH1-biased immune response. Boosting mice with monovalent or bivalent mRNA-LNPs provided rapid recall and long-lasting neutralizing antibody titers, an increase in antibody avidity and breadth that was held over time and generation of antigen-specific memory B- and T- cells. In hamsters, vaccination with GLB-COV2-043 led to lower viral loads, reduced incidence of SARS-CoV-2-related microscopic findings in lungs, and protection against weight loss after heterologous challenge with Omicron BA.1 live virus. Altogether, these data indicate that GLB-COV2-043 mRNA-LNP vaccine candidate elicits robust protective humoral and cellular immune responses and establishes our mRNA-LNP platform for subsequent clinical evaluations.
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COVID-19 , Cricetinae , Animais , Humanos , Camundongos , COVID-19/prevenção & controle , Vacinas contra COVID-19 , SARS-CoV-2/genética , Modelos Animais , RNA Mensageiro/genética , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunogenicidade da VacinaRESUMO
Molecular therapies exploiting mRNA vectors embody enormous potential, as evidenced by the utility of this technology for the context of the COVID-19 pandemic. Nonetheless, broad implementation of these promising strategies has been restricted by the limited repertoires of delivery vehicles capable of mRNA transport. On this basis, we explored a strategy based on exploiting the well characterized entry biology of adenovirus. To this end, we studied an adenovirus-polylysine (AdpL) that embodied "piggyback" transport of the mRNA on the capsid exterior of adenovirus. We hypothesized that the efficient steps of Ad binding, receptor-mediated entry, and capsid-mediated endosome escape could provide an effective pathway for transport of mRNA to the cellular cytosol for transgene expression. Our studies confirmed that AdpL could mediate effective gene transfer of mRNA vectors in vitro and in vivo. Facets of this method may offer key utilities to actualize the promise of mRNA-based therapeutics.
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Infecções por Adenoviridae , COVID-19 , Humanos , Adenoviridae/genética , Vetores Genéticos/genética , Técnicas de Transferência de Genes , Polilisina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pandemias , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , BiologiaRESUMO
Colorado potato beetle (CPB, Leptinotarsa decemlineata) is a major pest of potato and other solanaceous vegetables in the Northern Hemisphere. The insect feeds on leaves and can completely defoliate crops. Because of the repeated use of single insecticide classes without rotating active ingredients, many chemicals are no longer effective in controlling CPB. Ledprona is a sprayable double-stranded RNA biopesticide with a new mode of action that triggers the RNA interference pathway. Laboratory assays with second instar larvae fed Ledprona showed a dose-response where 25×10-6g/L of dsPSMB5 caused 90% mortality after 6days of initial exposure. We also showed that exposure to Ledprona for 6h caused larval mortality and decreased target messenger RNA (mRNA) expression. Decrease in PSMB5 protein levels was observed after 48h of larval exposure to Ledprona. Both PSMB5 mRNA and protein levels did not recover over time. Ledprona efficacy was demonstrated in a whole plant greenhouse trial and performed similarly to spinosad. Ledprona, currently pending registration at EPA, represents a new biopesticide class integrated pest management and insecticide resistance management programs directed against CPB.
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BACKGROUND: In the literature, there are few papers on long-term results after brace treatment and there is no consensus on whether scoliotic curves stop progressing at skeletal maturity. To date the factors that could influence curve behaviour following bracing have not been fully determined. AIM: The aim of this study was to evaluate the results and the loss of the scoliotic curve correction in a cohort of patients treated with Progressive Action Short Brace (PASB) brace during adolescence and to compare patient outcomes of under and over 30 Cobb degrees 10 years after brace removal. DESIGN: This is an observational controlled cohort study nested in a prospective clinical on-going database including 1536 patients with idiopathic scoliosis. SETTING: Inpatients and outpatients in Rome. POPULATION: The study enrolled 163 patients with idiopathic adolescent scoliosis who had been treated with the PASB brace at a 10 years minimum long-term follow-up examination. METHODS: One hundred sixty-three (female) patients with adolescent idiopathic scoliosis (AIS) treated with the Progressive Action Short Brace (PASB) at a mean age of 13.4 years (range 10-34) had accepted to undergo long-term follow-up examination. All patients had clinical and radiological examinations, but only 62 replied to some simple questions (including work status, pregnancy and pain) the population was divided into two groups based on Cobb degrees (< 30° and ≥ 30°). Statistical analysis was applied to test the efficacy of our hypothesis. RESULTS: The patients underwent a long-term follow-up after brace removal at a mean age of 13.46 years (±3.4). The prebrace mean curve was 28.98° (±7.918); after treatment, the mean was 13.88° and increased to a minimum of 15.35° in the 10 years following brace removal. However, there was no significant difference between the mean Cobb angle at the end of weaning and the mean Cobb angle at long-term follow-up. The curve angle at baseline of patients who were treated with a brace was reduced by 15° during the treatment, but at follow-up the curve size was found to have lost 2°. The over 30° group showed a prebrace scoliotic mean curve of 37.26°; at the end of weaning, the mean curve angle was 22.98° which increased to a mean of 25.07° at follow-up. The <30° group showed a prebrace scoliotic mean curve of 24.40° which, at the end of weaning, had reduced to a mean of 8.69°, increasing to 9.98° at follow-up. There was no significant difference in the mean progression of curve magnitude between the Ë 30° and ≥ 30° groups at the long-term follow-up. Work status was 62% full-time and 11% part-time. 24% had given birth. Three percent presented back pain related to instability of the spine. No patients underwent surgery after maturity but one patient had indication to surgical treatment. CONCLUSIONS: The PASB brace is effective for the treatment of lumbar and thoracolumbar scoliosis and is characterized by positive long-term outcomes, including in patients demonstrating moderate curves. In both groups, at 10-years minimum follow-up after bracing, scoliotic curves did not deteriorate beyond their original curve size after bracing in both groups at the 10-years minimum follow-ups. CLINICAL REHABILITATION IMPACT: At 10 years follow-up after bracing, scoliotic curves had not deteriorated beyond their original curve size.
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Braquetes , Progressão da Doença , Escoliose/terapia , Adolescente , Criança , Estudos de Coortes , Feminino , Seguimentos , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Fatores de TempoRESUMO
BACKGROUND: The recent literature showed positive results for bracing of patients with idiopathic scoliosis above 45° who refused surgery. However, no one has investigated whether other parameters can affect the results. AIM: The aim of this study was to evaluate the effectiveness of bracing in idiopathic scoliosis with curves above 40° and to verify the mechanical and biological parameters which go beyond the simple bend value expressed in Cobb degrees. DESIGN: This is an observational controlled cohort study nested in a prospective clinical on-going database including 1,238 patients with idiopathic scoliosis. SETTING: Inpatients and outpatients in Rome. POPULATION: The study enrolled 160 patients with idiopathic scoliosis with curves above 40°. METHODS: This is a prospective study based on an ongoing database including 1,238 patients with idiopathic scoliosis. The patients studied had idiopathic scoliosis with curves of 40° or more, Risser grade 0-4, and had refused any surgical treatment. 160 patients met the inclusion criteria. Of these, 104 patients had a definite outcome, 28 abandoned treatment and 28 are currently under treatment. The minimum duration of follow-up was 24 months. X-rays were used to obtain Cobb degrees and torsion of the apical vertebrae (Perdriolle's method). Three outcomes were distinguished according to SRS-SOSORT criteria: correction, stabilization and progression. To achieve the second aim, we divided the sample into subgroups according to Cobb degrees (<45°; ≥45°), Risser (0-2; 3-4) and rotation (<20; ≥20). Furthermore, logistic regression was applied by Stepwise Regression. RESULTS: The results of our study showed that in 104 patients with a definite outcome the Cobb mean value was initially 47±5.25 SD and 34.19 ±8.45 SD at follow-up. Perdriolle was initially 20.04±5.53 SD and 16.76±7.04 at follow-up. Overall, 81 patients (78%) obtained a curve correction, and stabilization was achieved in 14 cases (13%). Nine patients experienced curve progression (9%), 16 patients were recommended for surgery because the curve at follow up was over 45°. The analysis of subgroups shows that with Cobb <45° at baseline, the average reduction was 11.46° Cobb, while in cases with Cobb ≥45 at baseline, the mean correction was 13.74° Cobb. In subgroups with Perdriolle <20° at baseline, the average reduction was 16.02° Cobb, while in cases with Perdriolle ≥20° at baseline, the mean correction was 8.4° Cobb. In subgroups with Risser 0-2 at baseline, the average reduction was 14.7° Cobb, while in cases with Risser 3-4 at baseline, the mean correction was 6.7° Cobb. The logistic regression model shows significance for the initial value of Perdriolle and Risser. CONCLUSIONS: Our results indicate that an adequate conservative treatment must definitely be considered for patients with scoliotic curves who refuse surgery; the results will be better particularly if the rotation is lower than 20 and Risser is between 0-2. CLINICAL REHABILITATION IMPACT: With the simultaneous evaluation of the Cobb angle, the vertebral rotation and the potential vertebral growth, it was possible to predict the final results at the start of treatment.
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Braquetes , Escoliose/terapia , Adolescente , Criança , Feminino , Humanos , Itália , Masculino , Estudos Prospectivos , Escoliose/fisiopatologiaRESUMO
STUDY DESIGN: Prospective study in 150 consecutive outpatients affected by adolescent idiopathic scoliosis (AIS). OBJECTIVES: The purposes were to (1) identify a correlation between hump dimensions and the severity of scoliotic curve, and (2) evaluate how the treatment influenced the main parameters of scoliosis. SUMMARY OF BACKGROUND DATA: The existence of a relationship between clinical deformities and curve severity in AIS is still debated. Furthemore, only a few studies have investigated the effectiveness of conservative treatment for idiopathic scoliosis taking into account both clinical and radiologic factors. METHODS: 150 consecutive outpatients (mean age 12.8â±â1.9 years) affected by AIS were subjected to conservative brace-based treatment. 134 participants completed the treatment protocol. Two parameters were considered to evaluate the treatment progress: the hump and the Cobb angle. Measurements were determined at the beginning and the end of treatment. Statistical analyses were performed in the whole sample and after dividing the study participants into 4 subgroups: patients with lumbar (nâ=â66) or thoracic curves (nâ=â68), patients ranging in age between 6 and 13 years (nâ=â89) and patientsâ≥â14 years of age (nâ=â45). RESULTS: A positive correlation was detected between the hump dimension and curve severity at the beginning and the end of treatment, except for lumbar curves at baseline. The deformity was effectively corrected by the orthotic treatment (Cobb angle: 29.4â±â8.5° at baseline and 19.3â±â9.8° at the end of treatment; hump severity: 11.6â±â5.6âmm at baseline and 6.2â±â4.6âmm at the end). In addition, our data indicate that the hump correction is more evident than that of the curve registered in Cobb degrees. CONCLUSION: A significant correlation exists between the hump dimension and curve severity both at the beginning and the end of treatment, except for lumbar curves at baseline. The brace treatment confirmed its effectiveness in arresting the deformity progression and inducing a remodeling both of the scoliotic curve and the hump.
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Braquetes , Tratamento Conservador , Cifose/terapia , Escoliose/terapia , Adolescente , Criança , Progressão da Doença , Feminino , Humanos , Cifose/diagnóstico , Masculino , Estudos Prospectivos , Escoliose/diagnóstico , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
BACKGROUND: The factors influencing curve behavior following bracing are incompletely understood and there is no agreement if scoliotic curves stop progressing with skeletal maturity. The aim of this study was to evaluate the loss of the scoliotic curve correction in patients treated with bracing during adolescence and to compare patient outcomes of under and over 30 Cobb degrees, 10 years after brace removal. METHODS: We reviewed 93 (87 female) of 200 and nine patients with adolescent idiopathic scoliosis (AIS) who were treated with the Lyon or PASB brace at a mean of 15 years (range 10-35). All patients answered a simple questionnaire (including work status, pregnancy, and pain) and underwent clinical and radiological examination. The population was divided into two groups based on Cobb degrees (< 30° and > 30°). Statistical analysis was performed to test the efficacy of our hypothesis. RESULTS: The patients underwent a long-term follow-up at a mean age of 184.1 months (±72.60) after brace removal. The pre-brace scoliotic mean curve was 32.28° (± 9.4°); after treatment, the mean was 19.35° and increased to a minimum of 22.12° in the 10 years following brace removal. However, there was no significant difference in the mean Cobb angle between the end of weaning and long term follow-up period (p = 0.105). The curve angle of patients who were treated with a brace from the beginning was reduced by 13° during the treatment, but the curve size lost 3° at the follow-up period.The groups over 30° showed a pre-brace scoliotic mean curve of 41.15°; at the end of weaning, the mean curve angle was 25.85° and increased to a mean of 29.73° at follow-up; instead, the groups measuring ≤ 30° showed a pre-brace scoliotic mean curve of 25.58°; at the end of weaning, it was reduced to a mean of 14.24° and it increased to 16.38° at follow-up.There was no significant difference in the mean progression of curve magnitude between the ≤ 30° and > 30° groups at the long-term follow-up. CONCLUSIONS: Scoliotic curves did not deteriorate beyond their original curve size after bracing in both groups at the 15-year follow-ups. These results are in contrast with the history of this pathology that normally shows a progressive and lowly increment of the curve at skeletal maturity. Bracing is an effective treatment method characterized by positive long-term outcomes, including for patients demonstrating moderate curves.
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BACKGROUND: The Lyon brace is commonly prescribed in many European countries to patients with thoracic curves and is based on the three-point pressure system. The purpose of this study was to evaluate the efficacy of Lyon bracing for the conservative treatment of adolescent females with idiopathic thoracic curves in a case series selected on the basis of the Scoliosis Research Society (SRS) Committee on Bracing and Nonoperative Management Standardization Criteria and followed the guidelines on management of idiopathic scoliosis with corrective braces, proposed by the International Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT). METHODS: Prospective study based on an ongoing database. From 1297 patients treated for idiopathic scoliosis between 1995 and 2014 fulfill the inclusion criteria 102 patients treated with Lyon brace. Of these, 69 patients had a definite outcome, 17 have abandoned treatment e 16 are still in treatment. The 104 patients were adolescent females with curvatures in the thoracic spine and a pre-treatment Risser score ranging from 0 to 2. All patients were prescribed with full-time Lyon bracing. The minimum duration of follow-up was 24 months after the end of weaning (mean: 41.64 ± 31.45 months). Anteroposterior radiographs were used to estimate the curve magnitude (CM) at 5 time points: beginning of treatment (t1), one year after the beginning of treatment (t2), intermediate time between t1 and t4 (t3), end of weaning (t4), 2-year minimum follow-up from t4 (t5). Three outcomes were distinguished: curve correction, curve stabilization and curve progression. RESULTS: The results from our study showed that of the 69 patients with a definite outcome the CM mean value was 31.51° ± 4.34 SD at t1 and 20° ± 7.6 SD at t5. Curve correction was accomplished in 85.5 % of patients, curve stabilization was obtained in 13 % of patients and curve progression was evident in only 1.5 %. None of the patients were recommended surgery post-bracing. Of 17 patients who abandoned the treatment, at the time of abandonment (14.4 age) have achieved curve correction in 13 cases (77 %), stabilization in 53 cases (18 %) and progression in 1 case (5 %). CONCLUSION: The Lyon brace, through its biomechanical action on vertebral modeling, is highly effective in correcting thoracic curves in particularly when the SOSORT guidelines were adopted in addition to the SRS criteria.
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Braquetes , Escoliose/terapia , Adolescente , Criança , Feminino , Humanos , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: The Juvenile idiopathic scoliosis by age of onset, severity and evolutivity is source of great doubts concerning the purpose and use of conservative treatment. The different clinical experiences leave unsolved the question that arises in applying a conservative treatment when the patients are effectively forward a long growing period, in scoliosis characterized by inevitable evolutivity. The purpose of the present prospective study was to determine the effectiveness of conservative treatment in Juvenile idiopathic scoliosis. METHODS: From 1238 patients treated for idiopathic scoliosis between 1995 and 2012 fulfill the inclusion criteria 163 patients treated with PASB, Lyon brace and Milwaukee. Of these, 113 patients had a definite outcome, 27 have abandoned treatment e 23 are still in treatment. The minimum follow-up was 24 months. Radiographs were used to estimate the curve magnitude (CM) and the torsion of the apical vertebra (TA) at 5 time points: beginning (t1), 6 months after the beginning (t2), intermediate time between t1 and t4 (t3), end of weaning (t4), 2-years minimum follow-up (t5). Three outcomes were distinguished in agreement with SRS criteria: correction, stabilization and progression. RESULTS: The results from our study showed that of the 113 patients with a definite outcome CM mean value was 29.6 ± 7.5 SD at t1 and 16.9 ± 11.1 SD at t5. TA was 13.5 ± 5.4 SD at t1 and 8.5 ± 5.6 at t5. The variations between CM t5-t1 and TA t5-t1 were statistically significantly different. Curve correction was accomplished in 88 patients (77.8%), stabilization was obtained in 18 patients (15.9%). 7 patients (6.19%) have a progression and 4 of these were recommended for surgery. Of 26 patients who abandoned the treatment, at the time of abandonment (12.5 age) have achieved curve correction in 19 cases (70.0%), stabilization in 5 cases (19%) and progression in 3 cases (11%). Of these patients, reviewed at the end of growing, four have been operated on. CONCLUSIONS: Our study confirmed that conservative treatment with brace is highly effective in treating juvenile idiopathic scoliosis, in particular most patients reaching a complete curve correction and only 4.9% of patients need surgery.
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Cushing's Syndrome (CS) is rare in adolescence but the pathological effects of excessive circulating glucocorticoids concentration on bone during the developmental age still represent a challenge for orthopedists. Only few reports describe the gravity of early developed damages of spine in young affected by CS. A 18-years-old woman suffering from Cushing's Disease presented after many years treatment of the primary disease referring severe back pain and worsening back deformity. Radiological investigations showed vertebral collapses a devastating thoraco-lumbar scoliosis of 80° Cobb. Lumbar dual X-ray absorptiometry Z-score values were very low and consistent with severe osteoporosis. The patient was treated with bracing, antiresorptive therapy, calcium and vitamin D supplementation, and followed-up with imaging investigations to screen for further fractures. The bone mineral density will be monitored until its normalization will allow to plane surgical treatment in case of progression of spinal deformity and collapses. Early diagnosis and treatment of hypercortisolism, periodical clinical and radiographic follow-up, and treatment for the bone damage are mandatory to prevent the devastating sequelae of secondary osteoporosis.
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Síndrome de Cushing/diagnóstico por imagem , Fraturas Espontâneas/diagnóstico por imagem , Vértebras Lombares/lesões , Traumatismo Múltiplo/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Vértebras Torácicas/lesões , Adolescente , Síndrome de Cushing/terapia , Feminino , Fraturas Espontâneas/terapia , Humanos , Vértebras Lombares/efeitos da radiação , Traumatismo Múltiplo/terapia , Radiografia , Escoliose/terapia , Vértebras Torácicas/diagnóstico por imagem , Resultado do TratamentoRESUMO
BACKGROUND: The International Scientific Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT), that produced its first Guidelines in 2005, felt the need to revise them and increase their scientific quality. The aim is to offer to all professionals and their patients an evidence-based updated review of the actual evidence on conservative treatment of idiopathic scoliosis (CTIS). METHODS: All types of professionals (specialty physicians, and allied health professionals) engaged in CTIS have been involved together with a methodologist and a patient representative. A review of all the relevant literature and of the existing Guidelines have been performed. Documents, recommendations, and practical approach flow charts have been developed according to a Delphi procedure. A methodological and practical review has been made, and a final Consensus Session was held during the 2011 Barcelona SOSORT Meeting. RESULTS: The contents of the document are: methodology; generalities on idiopathic scoliosis; approach to CTIS in different patients, with practical flow-charts; literature review and recommendations on assessment, bracing, physiotherapy, Physiotherapeutic Specific Exercises (PSE) and other CTIS. Sixty-five recommendations have been given, divided in the following topics: Bracing (20 recommendations), PSE to prevent scoliosis progression during growth (8), PSE during brace treatment and surgical therapy (5), Other conservative treatments (3), Respiratory function and exercises (3), Sports activities (6), Assessment (20). No recommendations reached a Strength of Evidence level I; 2 were level II; 7 level III; and 20 level IV; through the Consensus procedure 26 reached level V and 10 level VI. The Strength of Recommendations was Grade A for 13, B for 49 and C for 3; none had grade D. CONCLUSION: These Guidelines have been a big effort of SOSORT to paint the actual situation of CTIS, starting from the evidence, and filling all the gray areas using a scientific method. According to results, it is possible to understand the lack of research in general on CTIS. SOSORT invites researchers to join, and clinicians to develop good research strategies to allow in the future to support or refute these recommendations according to new and stronger evidence.
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STUDY DESIGN: A prospective interventional study. OBJECTIVE: To determine the outcomes of adolescents affected by idiopathic lumbar scoliosis treated with a progressive action short brace (PASB). SUMMARY OF BACKGROUND DATA: The efficacy of conservative treatment of scoliosis is still debated. In a recent study, we showed that the PASB was effective in correcting deformities in adolescents with idiopathic thoracolumbar scoliosis. The purpose of the present study was to extend our preliminary findings by determining the results of PASB treatment in scoliotic adolescents with lumbar curves. METHODS: Patients were 40 adolescent girls (age [mean ± SD] = 11.6 ± 0.7 yr]) with lumbar curves and a pretreatment Risser score between 0 and 2. All patients were prescribed with a full-time PASB. The minimum duration of follow-up was 24 months (mean ± SD = 41.6 ± 34.5 mo). Anteroposterior radiographs were used to estimate the curve magnitude (CM) and the torsion of the apical vertebra (TA) at 5 time points: beginning of treatment (t1), 1 year after the beginning of treatment (t2), intermediate time between t1 and t4 (t3), end of weaning (t4), and 2-year minimum follow-up from t4 (t5). Three outcomes were distinguished: curve correction, curve stabilization, and curve progression. RESULTS.: A significant reduction in CM was achieved from t1 (Cobb angle [mean ± SD] = 26.4° ± 2.8) to t5 (Cobb angle [mean ± SD] = 13.8° ± 7.9; P < 0.001). Likewise, the PASB reduced TA from Perdriolle rotation angles of 10.8° (SD = 3.7) at t1 to 7.9° (SD = 4.2) at t5 (P < 0.05). Curve correction was accomplished in 82.5% of patients, whereas curve stabilization was obtained in 17.5% of patients. None of the patients experienced curve progression. CONCLUSION: The PASB allows a complete curve correction in most cases. No patients exhibited curve progression.
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Braquetes , Vértebras Lombares , Procedimentos Ortopédicos/instrumentação , Escoliose/terapia , Adolescente , Fenômenos Biomecânicos , Braquetes/normas , Criança , Feminino , Humanos , Itália , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Procedimentos Ortopédicos/normas , Guias de Prática Clínica como Assunto , Radiografia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Rotação , Escoliose/diagnóstico por imagem , Escoliose/fisiopatologia , Índice de Gravidade de Doença , Fatores de Tempo , Torção Mecânica , Resultado do TratamentoRESUMO
The rheological properties of the environment in which a cell lives play a key role in how the cells will respond to that environment and may modify cell proliferation, morphology and differentiation. Effective means of modifying these properties are needed, particularly for peptide hydrogels which are generally relatively weak and soft. In this report we describe the enzymatic cross-linking of a nanofibrous multidomain peptide hydrogel. When this method was used, the storage modulus, G', could be increased to over 4000 Pa without changes in hydrogel concentration and without dramatic changes in nanostructural architecture. Enzymatic cross-linking represents a mild and simple method for increasing the mechanical strength of peptide hydrogels in applications for which the robustness of the gel is essential. This method should be suitable for a broad array of peptide hydrogels containing lysine such as those currently under study by many different groups.
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Hidrogéis/química , Hidrogéis/síntese química , Peptídeos/química , Peptídeos/síntese química , Proteína-Lisina 6-Oxidase/química , HumanosRESUMO
INTRODUCTION AND OBJECTIVES: Physical deformities caused by adolescent idiopathic scoliosis (AIS) coupled with conservative treatment of AIS with orthesis unavoidably impacts on patients' quality of life (QoL). The present study aimed at evaluating the QoL in patients affected by AIS treated with brace. The study also sought to determine the ability of different QoL questionnaires to monitor QoL over the course of treatment. MATERIALS AND METHODS: Data were collected in 108 consecutive patients (96 females, 16 males) affected by AIS admitted to the outpatient orthopaedic clinic of the Catholic University of the Sacred Heart in Rome (Italy). Patients were subjected to full-time (i.e., 22 hrs per day) conservative treatment with the progressive action short brace (PASB), the Lyon brace or a combination of PASB + Lyon brace. Three instruments were used for QoL determination: the Scoliosis Research Society 22 (SRS-22), Bad Sobernheim Stress Questionnaire (BSSQ) and the Brace Questionnaire (BrQ). RESULTS: A significant correlation was detected among the 3 scores (p < 0.001). The BrQ possesses a higher capacity to detect changes in QoL in relation to the patient gender, type of brace, curve severity at baseline and at the completion of treatment, and curve type. Overall, boys displayed a higher QoL than girls. In all 3 questionnaires, higher QoL scores were determined in patients treated with the PASB compared with those using the Lyon brace. QoL scores were significantly correlated with the curve severity. Higher QoL scores were obtained by participants with thoraco-lumbar curves as compared with those with other curves. CONCLUSIONS: The 3 questionnaires are effective in capturing changes in QoL in AIS patients subjected to conservative treatment. However, the BrQ possesses a higher discriminatory capacity compared with the other questionnaires tested. PASB-based treatment is associated with better QoL than the Lyon bracing.
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Sarcopenia, the age-related decline in muscle mass and function, represents a significant health issue due to the high prevalence of frailty and disability associated with this condition. Nevertheless, the cellular mechanisms responsible for the loss of muscle mass in old age are still largely unknown. An altered regulation of myocyte apoptosis has recently emerged as a possible contributor to the pathogenesis of sarcopenia. Studies in animal models have shown that the severity of skeletal muscle apoptosis increases over the course of aging and correlates with the degree of muscle mass and strength decline. Several apoptotic pathways are operative in aged muscles, with the mitochondria- and TNF-alpha-mediated pathways likely being the most relevant to sarcopenia. However, despite the growing number of studies on the subject, a definite mechanistic link between myocyte apoptosis and age-related muscle atrophy has not yet been established. Furthermore, the evidence on the role played by apoptosis in human sarcopenia is still sparse. Clearly, further research is required to better define the involvement of myocyte apoptosis in the pathogenesis of muscle loss at advanced age. This knowledge will likely help in the design of more effective therapeutic strategies to preserve muscle mass into old age, thus fostering independence of the elderly population and reducing the socioeconomic burden associated with sarcopenia.
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Envelhecimento/fisiologia , Apoptose , Sarcopenia/fisiopatologia , Humanos , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
Multidomain peptides are a class of amphiphilic self-assembling peptides with a modular ABA block motif in which the amphiphilic B block drives self-assembly while the flanking A blocks, which are electrostatically charged, control the conditions under which assembly takes place. Previously we have shown that careful selection of the amino acids in the A and B blocks allow one to control the self-assembled fiber length and viscoelastic properties of formed hydrogels. Here we demonstrate how the modular nature of this peptide assembler can be designed for biological applications. With control over fiber length and diameter, gelation conditions, and viscoelastic properties, we can develop suitable materials for biological applications. Going beyond a simple carrier for cell delivery, a biofunctional scaffold will interact with the cells it carries, promoting advantageous cell-matrix interactions. We demonstrate the design of a multidomain peptide into a bioactive variant by incorporation of a matrix metalloprotease 2 (MMP-2) specific cleavage site and cell adhesion motif. Gel formation and rheological properties were assessed and compared to related peptide hydrogels. Proteolytic degradation by collagenase IV was observed in a gel weight loss study and confirmed by specific MMP-2 degradation monitored by mass spectrometry and cryo-transmission electron microscopy (cryo-TEM). Combination of this cleavage site with the cell adhesion motif RGD resulted in increased cell viability and cell spreading and encouraged cell migration into the hydrogel matrix. Collectively the structural, mechanical, and bioactive properties of this multidomain peptide hydrogel make it suitable as an injectable material for a variety of tissue engineering applications.
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Movimento Celular , Tamanho Celular , Endopeptidases/metabolismo , Hidrogéis/síntese química , Peptídeos/química , Adesão Celular , Proliferação de Células , Células Cultivadas , Endopeptidases/química , Humanos , Hidrogéis/química , Dente Decíduo/citologiaRESUMO
BACKGROUND: The effectiveness of conservative treatment of scoliosis is controversial. Some studies suggest that brace is effective in stopping curve progression, whilst others did not report such an effect.The purpose of the present study was to effectiveness of Progressive Action Short Brace (PASB) in the correction of thoraco-lumbar curves, in agreement with the Scoliosis Research Society (SRS) Committee on Bracing and Nonoperative Management Standardisation Criteria. METHODS: Fifty adolescent females (mean age 11.8 +/- 0.5 years) with thoraco-lumbar curve and a pre-treatment Risser score ranging from 0 to 2 have been enrolled. The minimum duration of follow-up was 24 months (mean: 55.4 +/- 44.5 months). Antero-posterior radiographs were used to estimate the curve magnitude (CM) and the torsion of the apical vertebra (TA) at 5 time points: beginning of treatment (t1), one year after the beginning of treatment (t2), intermediate time between t1 and t4 (t3), end of weaning (t4), 2-year minimum follow-up from t4 (t5). Three situations were distinguished: curve correction, curve stabilisation and curve progression.The Kruskal Wallis and Spearman Rank Correlation tests have been used as statistical tests. RESULTS: CM mean value was 29,30 +/- 5,16 SD at t1 and 14,67 +/- 7,65 SD at t5. TA was 12.70 +/- 6,14 SD at t1 and 8,95 +/- 5,82 at t5. The variation between measures of Cobb and Perdriolle degrees at t1,2,3,4,5 and between CM t5-t1 and TA t5-t1 were significantly different.Curve correction was accomplished in 94% of patients, whereas a curve stabilisation was obtained in 6% of patients. CONCLUSION: The PASB, due to its peculiar biomechanical action on vertebral modelling, is highly effective in correcting thoraco-lumbar curves.
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An important goal in supramolecular chemistry is to achieve controlled self-assembly of molecules into well-defined nanostructures and the subsequent control over macroscopic properties resulting from the formation of a nanostructured material. Particularly important to our lab is control over viscoelasticity and bioactivity. Recently we described a multidomain peptide motif that can self-assemble into nanofibers 2 x 6 x 120 nm. In this work we describe how sequence variations in this general motif can be used to create nanofibrous gels that have storage moduli, which range over 2 orders of magnitude and can undergo shear thinning and shear recovery while at the modest concentration of 1% by weight. Gel formation is controlled by addition of oppositely charged multivalent ions such as phosphate and magnesium and can be carried out at physiological pH. We also demonstrate how maximum strength can be obtained via covalent capture of the nanofibers through disulfide bond formation. Together these hydrogel properties are ideally suited as injectable materials for drug and cell delivery.
Assuntos
Materiais Biocompatíveis/síntese química , Nanoestruturas/química , Peptídeos/química , Sequência de Bases , Reagentes de Ligações Cruzadas , Dissulfetos , Géis , Íons , ViscosidadeRESUMO
We present a series of short, multidomain peptides as biocompatible solubilizing agents of single-walled carbon nanotubes (SWCNTs). These peptides are organized into an ABA block motif, where the A block is composed of charged amino acids, such as glutamic acid, and the B block is composed of alternating hydrophilic and hydrophobic residues. The hydrophobic amino acid residues interact with SWCNT sidewalls, while the hydrophilic residues interact primarily with water in an aqueous solution. When many peptides assemble along the length of the nanotube, it becomes effectively encapsulated within a peptide nanofiber. This noncovalent interaction between the peptide and the nanotube solubilizes SWCNTs while keeping the electronic structure of the nanotube intact, thereby preserving the optical and electrical properties that make SWCNTs promising for use in biological applications. To assess the toxicity of these peptide coatings, they were added to cultures of NIH 3T3 mouse fibroblasts and the effect on cell viability was measured. Toxicity was found to be far lower than for ionic surfactants typically used for SWCNT suspension and similar to Pluronics. The near-IR fluorescence intensity of SWCNTs in peptide suspensions was comparable to that in Pluronics. Five surfactants were tested for their effect on the proliferation of NIH 3T3 cells with and without SWCNTs. Although some differences were observed among surfactants, in no case did the presence of SWCNTs make a statistically significant difference. Based on their ability to solubilize SWCNTs, the fluorescence of the suspended tubes, their minimal impact on cell viability, and their potential for easy chemical modification, multidomain peptides have been found to have excellent potential as a biocompatible surfactant for suspension of SWCNTs.
Assuntos
Nanotubos de Carbono/química , Fragmentos de Peptídeos/química , Tensoativos/química , Animais , Camundongos , Microscopia de Força Atômica , Células NIH 3T3 , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/isolamento & purificação , Poloxâmero/químicaRESUMO
HOX genes encode conserved transcription factors that control the morphological diversification along the anteroposterior body axis. HOX proteins bind to DNA through a highly conserved 60 amino acid sequence called the homeodomain, and greater DNA binding specificity and stability are achieved when it forms complexes with cofactors such as PBX and MEIS in humans. In particular, HOX proteins from paralog groups 1-8, interact with PBX proteins via a specific and highly conserved hydrophobic six amino acid sequence localized in the N-terminal region of HOX. In several oncogenic transformations, deregulated HOX gene expression has been observed, indicating an involvement of these transcriptional regulators in carcinogenesis and metastasis. Inhibition of the HOX-PBX interaction could be a strategy to control the abnormal proliferation of these cancer cells. In this study we describe a small designed peptide amphiphile (PA) which self-assembles into micelles and shows inhibition of T3M4 pancreatic cancer cells, K562 leukemia cells and MJT1 melanoma cells while non-cancerous fibroblast NIH 3T3 cells are less affected. This molecule contains three critical regions: a 9-amino-acid sequence designed to disrupt HOX/PBX/DNA complex formation, a 16-amino-acid sequence to deliver the peptide into the cell and a 16-carbon-acyl chain which we show leads to the molecule's self-assembly and significantly enhances the effectiveness of the molecule to slow cell proliferation.