Balancing biological and biomechanical performance in intervertebral disc repair: a systematic review of injectable cell delivery biomaterials.

Discogenic back pain is a common condition without approved intervertebral disc (IVD) repair therapies. Cell delivery using injectable biomaterial carriers offers promise to restore disc height and biomechanical function, while providing a functional niche for delivered cells to repair degenerated tissues. This systematic review advances the injectable IVD cell delivery biomaterials field by characterising its current state and identifying themes of promising strategies. Preferred Reporting Items for Systematic Reviews and Meta- Analyses (PRISMA) guidelines were used to screen the literature and 183 manuscripts met the inclusion criteria. Cellular and biomaterial inputs, and biological and biomechanical outcomes were extracted from each study. Most identified studies targeted nucleus pulposus (NP) repair. No consensus exists on cell type or biomaterial carrier, yet most common strategies used mesenchymal stem cell (MSC) delivery with interpenetrating network/co-polymeric (IPN/CoP) biomaterials composed of natural biomaterials. All studies reported biological outcomes with about half the studies reporting biomechanical outcomes. Since the IVD is a load-bearing tissue, studies reporting compressive and shear moduli were analysed and two major themes were found. First, a competitive balance, or 'seesaw' effect, between biomechanical and biological performance was observed. Formulations with higher moduli had inferior cellular performance, and vice versa. Second, several low-modulus biomaterials had favourable biological performance and matured throughout culture duration with enhanced extracellular matrix synthesis and biomechanical moduli. Findings identify an opportunity to develop next-generation biomaterials that provide high initial biomechanical competence to stabilise and repair damaged IVDs with a capacity to promote cell function for long-term healing.

Impact of Phyllantus niruri and Lactobacillus amylovorus SGL 14 in a mouse model of dietary hyperoxaluria.

Hyperoxaluria is a pathological condition which affects long-term health of kidneys. The present study evaluates the impact of the combination of Lactobacillus amylovorus SGL 14 and the plant extract Phyllantus niruri (namely Phyllantin 14™) on dietary hyperoxaluria. Safety and efficacy of Phyllantin 14 have been evaluated in vivo. Mice C57BL6 fed a high-oxalate diet were compared to mice fed the same diet administered with Phyllantin 14 by gavage for 6 weeks. Control mice were fed a standard diet without oxalate. No adverse effects were associated to Phyllantin 14 supplementation, supporting its safety. Mice fed a high-oxalate diet developed significant hyperoxaluria and those administered with Phyllantin 14 showed a reduced level of urinary oxalate and a lower oxalate-to-creatinine ratio. Soluble and insoluble caecal oxalate were significantly lower in treated group, a finding in agreement with the colonisation study, i.e. mice were colonised with SGL 14 after 3 weeks. Microbiota analysis demonstrated that both oxalate diet and Phyllantin 14 can differently modulate the microbiota. In conclusion, our findings suggest that Phyllantin 14 supplementation represents a potential supportive approach for reducing urinary oxalate and/or for enhancing the efficacy of existing treatments.

Crosslinker concentration controls TGFß-3 release and annulus fibrosus cell apoptosis in genipin-crosslinked fibrin hydrogels.

Back pain is a leading cause of global disability associated with intervertebral disc (IVD) pathologies. Discectomy alleviates disabling pain caused by IVD herniation without repairing annulus fibrosus (AF) defects, which can cause accelerated degeneration and recurrent pain. Biological therapies show promise for IVD repair but developing high-modulus biomaterials capable of providing biomechanical stabilisation and delivering biologics remains an unmet challenge. The present study identified critical factors and developed an optimal formulation to enhance the delivery of AF cells and transforming growth beta-3 (TGFß-3) in genipin-crosslinked fibrin (FibGen) hydrogels. Part 1 showed that AF cells encapsulated in TGFß-3-supplemented high-modulus FibGen synthesised little extracellular matrix (ECM) but could release TGFß-3 at physiologically relevant levels. Part 2 showed that AF cells underwent apoptosis when encapsulated in FibGen, even after reducing fibrin concentration from 70 to 5 mg/mL. Mechanistic experiments, modifying genipin concentration and integrin binding site presence demonstrated that genipin crosslinking caused AF cell apoptosis by inhibiting cell-biomaterial binding. Adding integrin binding sites with fibronectin partially rescued apoptosis, indicating genipin also caused acute cytotoxicity. Part 3 showed that FibGen formulations with 1 mg/mL genipin had enhanced ECM synthesis when supplemented with fibronectin and TGFß-3. In conclusion, FibGen could be used for delivering biologically active compounds and AF cells, provided that formulations supplied additional sites for cell-biomaterial binding and genipin concentrations were low. Results also highlighted a need for developing strategies that protect cells against acute crosslinker cytotoxicity to overcome challenges of engineering high-modulus cell carriers for musculoskeletal tissues that experience high mechanical demands.

Probiotic Bifidobacterium lactis, anti-oxidant vitamin E/C and anti-inflammatory dha attenuate lung inflammation due to pm2.5 exposure in mice.

The incidence of asthma and allergic diseases of the airways is constantly increasing, both in the industrialised and developing countries, due to harmful and excessive quantities of air pollution. Although some studies have shown an effect of dietary supplementation of specific nutrients (especially with anti-oxidant and anti-inflammatory properties) in reducing airways inflammatory response, the results are not yet conclusive and the science is still at its infancy. Our hypothesis is that combining such nutrients could provide more benefits than using them alone. The aim of the research project proposed here is to investigate whether specific combinations of nutrients (docosahexanoic acid, vitamin C and E, and Bifidobacterium lactis strain BB-12®, included in an engineered diet) can act synergistically to reduce inflammation given by high level of air pollution. Beside the role of docosahexanoic acid, vitamins C and E on airways inflammatory disease, no study examined the effect of the supplementation of this probiotic strain in pathological conditions caused by air pollution so far. Herein we used a well-established in vivo model for the study of pollution effects, which consists in female BALB/c mice receiving by pharyngeal aspiration either a sham or a particulate matter with diameter <2.5 µm (PM 2.5) containing aerosol. Before treatment, mice were fed either a chow or a supplemented diet. By performing histological analyses and gene expression profiles on lung sections and serum measurement of the cytokine interleukin 10, we found that a specific combination of all the aforementioned nutrients rather than nutrients alone had a synergistic protective effect against PM2.5-induced inflammation. In conclusion, our study support that a supplemental nutritional intervention based on a combination of the probiotic B. lactis BB-12, the anti-oxidant vitamin C and E, and the anti-inflammatory docosahexanoic acid represents a rational option for alleviating air pollution-related lung inflammation.

Osteosarcoma en niños y adolescentes: reporte definitivo del brazo pediátrico del grupo cooperativo venezolano para el estudio de los tumores óseos (GCVETO): octubre 1995-diciembre 1999 / Osteosarcoma in children and adolescen: report definitive of the arm pediatric of the group cooperative venexuelan for study od the tumors osseous (GCVETO): octuber 1995-december 1999

En 1995 se integró el GCVETO, y en octubre 1995 se inicia el Protocolo 003/95 para el estudio y tratamiento del Osteosarcoma (OS). Durante el período comprendido entre el 01.10.1995 y el 31.12.1999, 39 pacientes menores de 20 años ingresaron al brazo pediátrico del protocolo 003/95. El esquema de quimioterapia incluyó: Ifosfamida (IFOS)/Mesna 1800 mgr/m²/día/5 días, Doxorubicina (DOXO) 25 mgr/m²/día/3 días asociado a ICRF-187 (Desraxozane)250 mgr/m²/día/3 días, Cisdiaminodicloroplatino (CDDP) 40 mgr/m²/día/3 días. 64,10 por ciento eran varones, con una relación sexo V:H 1,78:1. 53,84 por ciento tenían edades comprendidas entre 10 y 15 años, edad mínima 6 a. y máxima 20 a., con un promedio de 12,53 a. Dolor, aumento de volumen e incapacidad funcional fueron los datos clínicos más frecuentes. 100 por ciento de los casos presentaban compromiso de partes blandas, y en 30,78 por ciento el volumen tumoral fue > 20 cm. El sitio de localización más frecuente: Femúr 48,7 por ciento, seguido por Tibia 23,07 por ciento y Húmero 20,51 por ciento. 14 pacientes presentaron enfermedad metastásica al ingreso. Las alteraciones de laboratorio más relevantes: Velocidad Sedimentación Globular (VSG), niveles séricos de Fosfatasa Alcalina (FA) y Deshidrogenasa Láctica (LDH). Los estudios imagenológicos del hueso comprometido fueron positivos en todos los casos, orientando el diagnóstico clínico en el 100 por ciento de los mismos. En todos los casos se estableció el diagnóstico a través del estudio histológico. 34 pacientes (87,18 por ciento) se consideraron evaluables para la terapia. Cirugía definitiva se realiza en el 61,76 de los casos: Injerto Oseo 11 pacientes, Desarticulación 8 pacientes, Resección tumoral 1 paciente, Amputación 1 paciente, Endoprótesis 1 paciente. 226 cursos de quimioterapia fueron administrados, promedio de 5,79 ciclos. 17 pacientes (50 por ciento) han finalizado la terapia. La respuesta histológica se evaluó según porcentaje de necrosis sólo en 16 pacientes (72,72 por ciento): Grado I 2/16, Grado II 3/16, Grado III 7/16, Grado IV 3/16, N.R. 6/22. R.C., fue obtenida en 19 pacientes (55,88 por ciento): 16/22 pacientes sin enfermedad metastásica y 3/12 con enfermedad metastásica. R.P. 13 pacientes, Progresión 2 pacientes, 8 pacientes fallaron a la terapia: Los sitios de recaída más frecuentes: Pulmón y Hueso (50 por ciento)