No abstract

No abstract

No abstract

Calcium phosphate (CaP) bioceramics, especially hydroxyapatite (HA), have been used as coatings on implants owing to their biocompatible properties. The commercial practice for applying HA coating, plasma spraying, has some disadvantages which limit the long-term stability of the implants. Pulsed laser deposition (PLD) is being investigated as an alternative technique. The purpose of this research was to systematically study the effect of various parameters of the PLD process on the properties of CaP coatings. In this study, three types of HA targets and two laser wavelengths were used to make six categories of coatings. Predominantly crystalline HA coatings were produced under all six categories at optimum conditions, although small amounts of minor phases sometimes were found. Sufficient coating/substrate bond strength was also obtained. A wide variety of coating morphologies was obtained, from rather dense and uniform to rough and porous. The important factors that affected the morphology included target properties, vacuum level, deposition temperature, and laser wavelength and energy density. PLD's ability to produce both amorphous and crystalline, and both smooth/dense and rough/porous coatings may be a unique advantage.

Hydroxyapatite (HA) coatings generally exhibit very good biocompatibility owing to their compositional resemblance to the natural hard tissue and to bioactive properties that are directly related to surface transformations in physiological fluids. In this study, two types of porous HA coatings produced with pulsed laser deposition were tested with respect to their dissolution/reprecipitation in a semidynamic simulated physiological solution. Coatings with higher porosity produced with a 355-nm wavelength laser exhibited significant reprecipitation earlier than those produced with a 266-nm wavelength laser. The dissolution of the non-HA phases played a major role in the reprecipitation of HA-like material as indicated by X-ray diffraction (XRD). The coatings' Ca/P ratio became closer to the theoretical value of HA. The newly formed HA had imperfect crystal structure and/or small crystal size as suggested by XRD. The reprecipitation resulted in a very dense morphology as shown by scanning electron microscopy, suggesting a mechanically strong structure after reprecipitation. Despite undergoing dissolution and reprecipitation, the coatings showed sufficient stability in the solution, as XRD and energy-dispersive X-ray studies indicated no significant loss of the coatings. The stability of these HA coatings and their ability to cause reprecipitation of HA in the simulated physiological solution showed the potential of these coatings for clinical applications.

Calcium phosphate (CaP) bioceramics, especially hydroxyapatite (HA), have been used as coatings on implants owing to their biocompatible properties. The commercial practice for applying HA coating, plasma spraying, has some disadvantages which limit the long-term stability of the implants. Pulsed laser deposition (PLD) is being investigated as an alternative technique. The purpose of this research was to systematically study the effect of various parameters of the PLD process on the properties of CaP coatings. In this study, three types of HA targets and two laser wavelengths were used to make six categories of coatings. Predominantly crystalline HA coatings were produced under all six categories at optimum conditions, although small amounts of minor phases sometimes were found. Sufficient coating/substrate bond strength was also obtained. A wide variety of coating morphologies was obtained, from rather dense and uniform to rough and porous. The important factors that affected the morphology included target properties, vacuum level, deposition temperature, and laser wavelength and energy density. PLD's ability to produce both amorphous and crystalline, and both smooth/dense and rough/porous coatings may be a unique advantage.

Background Organizing pneumonia (OP) is a secondary process in many diseases. Due to its low incidence and indistinct symptoms, there is limited information on OP associated with haematological malignancies. Therefore, the aim of this study was to discuss the characteristics and prognosis of OP associated with haematological malignancies. Methods We observed and analysed pathologically confirmed OP cases associated with haematological malignancies in a hospital record database and excluded cases of OP with known causes, including chemotherapy, radiotherapy, targeted therapy, transplantation and infection. Results There were five patients with OP underlying only haematological malignancies, including one case each of the following: myelodysplastic syndrome, acute myelogenous leukaemia, multiple myeloma, aplastic anaemia, and T cell lymphoma. Radiological findings did not show a distinct pattern, and two cases mimicked pulmonary aspergillosis with ground-glass opacity (GGO). The diagnosis of OP was confirmed by minimal invasive biopsy. Although all patients developed severe cases, steroids yielded favourable outcomes. Conclusion This study demonstrates that haematological malignancies may be a cause of OP and that minimal invasive biopsy may be an effective and safe method to confirm the diagnosis. Although OP associated with haematological malignancies may more frequently develop into severe cases, the OP lesions were steroid-responsive during follow-up.

Background Interstitial lung diseases (ILD) encompass a heterogenous group of diffuse parenchymal lung disorders characterized by variable degrees of inflammation and fibrosis. Pretherapeutic clinical testing models for such diseases can serve as a platform to test and develop effective therapeutic strategies. In this study, we developed patient derived 3D organoid model to recapitulate the disease process of ILDs. We characterized the inherent property of invasiveness in this model and tested for antifibrotic responses with an aim to develop a potential platform for personalized medicine in ILDs. Methods In this prospective study, 23 patients with ILD were recruited and underwent lung biopsy. 3D organoid-based models (pulmospheres) were developed from the lung biopsy tissues. Pulmonary functioning testing and other relevant clinical parameters were collected at the time of enrollment and follow up visits. The patient derived pulmospheres were compared to normal control pulmospheres obtained from 9 explant lung donor samples. These pulmospheres were characterized by their invasive capabilities and responsiveness to the antifibrotic drugs, pirfenidone and nintedanib. Results Invasiveness of the pulmospheres was measured by the zone of invasiveness percentage (ZOI%). The ILD pulmospheres (n = 23) had a higher ZOI% as compared to control pulmospheres (n = 9) (516.2 ± 115.6 versus 54.63 ± 19.6 respectively. ILD pulmospheres were responsive to pirfenidone in 12 of the 23 patients (52%) and responsive to nintedanib in all 23 patients (100%). Pirfenidone was noted to be selectively responsive in patients with connective tissue disease related ILD (CTD-ILD) at low doses. There was no correlation between the basal pulmosphere invasiveness, response to antifibrotics, and FVC change (Δ FVC). Conclusions The 3D pulmosphere model demonstrates invasiveness which is unique to each individual subject and is greater in ILD pulmospheres as compared to controls. This property can be utilized to test responses to drugs such as antifibrotics. The 3D pulmosphere model could serve as a platform for the development of personalized approaches to therapeutics and drug development in ILDs and potentially other chronic lung diseases.