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Autogenous bone graft is the gold standard for fusion procedure. However, pain at donor site and inconsistent outcome have left a surgeon to venture into some other technique for spinal fusion. The objective of this study was to determine whether osteogenesis induced bone marrow stem cells with the combination of ceramics granules (HA or TCP/HA), and fibrin could serve as an alternative to generate spinal fusion. The sheep's bone marrow mesenchymal stem cells (BMSCs) were aspirated form iliac crest and cultured for several passages until confluence. BMSCs were trypsinized and seeded on hydroxyapatite scaffold (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) for further osteogenic differentiation in the osteogenic medium one week before implantation. Six adult sheep underwent three-level, bilateral, posterolateral intertransverse process fusions at L1-L6. Three fusion sites in each animal were assigned to three treatments: (a) HA constructs group/L1-L2, (b) TCP/HA constructs group/L2-L3, and (c) autogenous bone graft group/L5-L6. The spinal fusion segments were evaluated using radiography, manual palpation, histological analysis and scanning electron microscopy (SEM) 12 weeks post implantation. The TCP/HA constructs achieved superior lumbar intertransverse fusion compared to HA construct but autogenous bone graft still produced the best fusion among all.

Biomaterial, an essential component of tissue engineering, serves as a scaffold for cell attachment, proliferation, and differentiation; provides the three dimensional (3D) structure and, in some applications, the mechanical strength required for the engineered tissue. Both synthetic and naturally occurring calcium phosphate based biomaterial have been used as bone fillers or bone extenders in orthopedic and reconstructive surgeries. This study aims to evaluate two popular calcium phosphate based biomaterial i.e., hydroxyapatite (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) granules as scaffold materials in bone tissue engineering. In our strategy for constructing tissue engineered bone, human osteoprogenitor cells derived from periosteum were incorporated with human plasma-derived fibrin and seeded onto HA or TCP/HA forming 3D tissue constructs and further maintained in osteogenic medium for 4 weeks to induce osteogenic differentiation. Constructs were subsequently implanted intramuscularly in nude mice for 8 weeks after which mice were euthanized and constructs harvested for evaluation. The differential cell response to the biomaterial (HA or TCP/HA) adopted as scaffold was illustrated by the histology of undecalcified constructs and evaluation using SEM and TEM. Both HA and TCP/HA constructs showed evidence of cell proliferation, calcium deposition, and collagen bundle formation albeit lesser in the former. Our findings demonstrated that TCP/HA is superior between the two in early bone formation and hence is the scaffold material of choice in bone tissue engineering.

This is a retrospective study of the epidemiology, clinical features, laboratory findings, treatment and outcome of haemorrhagic disease in 42 Kelantanese infants who were admitted to Hospital Universiti Sains Malaysia during a 2-year period (1987-1988). Classical haemorrhagic disease of the newborn was the commonest presentation (48%), followed by early onset (29%) and late onset (24%) disease. Home deliveries accounted for 81% of the affected infants. Most of these babies were not given vitamin K at birth in contrast to those delivered in hospitals. All except one infant were breastfed. The six commonest presenting clinical features were pallor, jaundice, umbilical cord bleeding, tense fontanelle, convulsions and hepatomegaly. All the infants had prolonged prothrombin and partial thromboplastin times which were corrected by administration of vitamin K. Subdural haemorrhage was the commonest form of intracranial haemorrhage, followed by subarachnoid haemorrhage. The overall case fatality rate was 14%. The results of this study once again emphasize the value of vitamin K prophylaxis in the newborn.A retrospective study of 42 newborns who were admitted to the Hospital Universiti Sains Malaysia for spontaneous bleeding and prolonged prothrombin and partial thromboplastin times during 1987-1988 was conducted to determine the epidemiology, clinical features, laboratory findings, treatment, and outcome of hemorrhagic disease of the newborn (HDN). The infants came from households in the rural state of Kelantan. In Kelantan, the estimated overall annual incidence of severe HDN was 1/1900 live births. None of the infants had bleeding due to inherited coagulopathy or disseminated intravascular coagulation. The categories of HDN were classical HDN (48%), early onset HND (29%), and late onset HND (24%). The most frequent clinical manifestations of HDN were pallor, jaundice, umbilical cord bleeding, tense fontanelle, convulsions, and hepatomegaly. 81% of the infants were delivered at home. Only 7 infants received vitamin K at birth. Anemia was common, especially in cases with massive intracranial bleeds. Most intracranial hemorrhages were subdural hemorrhages. The mothers of all infants, except one, breast fed. All infants received intravenous vitamin K at an initial dose of 1-5 mg/daily, which returned the prolonged prothrombin time and partial prothrombin time to normal. 33 infants recovered completely. One infant with classical HDN was mentally retarded and had hydrocephalus. Another infant also with classical HDN was mentally retarded. The overall case fatality rate was 14%. The case fatality rate for late HDN was 30%. These findings stress the importance of vitamin K prophylaxis in the newborn.

An unusual case of intravascular bronchioloalveolar tumour in a 40-year-old Chinese woman is reported. The woman has survived 20 years after radiological abnormalities were first noted in her lungs. This slowly progressing endothelial lung tumour has only recently been recognized as a distinct pathological entity.

Pyroclastic soils cover significant parts of the world's surface, including areas occupied by urban settlements, vital structures and infrastructures. Despite these materials present significant physical and mechanical differences from site to site, posing sometimes severe geotechnical problems, a comprehensive and worldwide accepted geotechnical classification still lacks. The Campania Region, at the centre of which rises the town of Naples, is covered by pyroclastic soils accumulated in the last tens of thousands of years as a result of volcanic activity. The examples reported in the paper show that the index, state, hydraulic and mechanical properties of these materials depend on the distance from the eruptive centre and mechanism of deposition. The overall geotechnical framework arising from this review highlights the peculiarities of pyroclastic soils, adding further information to the general knowledge about the properties and behaviour of natural soils. © 2007 Taylor & Francis Group, London.