Thermal Conductivity of Some Major Building Materials in Saudi Arabia

The objective of this work was to measure the thermal conductivity of the more common building materials used in Saudi Arabia and compare the results with the data reported in handbooks These materials included seven types of clay bricks, one type of sandlime bricks, five types of concrete blocks and one type of pre fabricated wall The study shows that, although the thermal conductivities of these materials lie within the range of the values reported in handbooks, they are on the higher side of the range.

Overexpression of PIK3CA in murine head and neck epithelium drives tumor invasion and metastasis through PDK1 and enhanced TGFβ signaling

Head and neck squamous cell carcinoma (HNSCC) patients have a poor prognosis, with invasion and metastasis as major causes of mortality. The phosphatidylinositol 3-kinase (PI3K) pathway regulates a wide range of cellular processes crucial for tumorigenesis, and PIK3CA amplification and mutation are among the most common genetic alterations in human HNSCC. Compared to the well-documented roles of the PI3K pathway in cell growth and survival, the roles of the PI3K pathway in tumor invasion and metastasis have not been well delineated. We generated a PIK3CA-genetically engineered mouse model (PIK3CA-GEMM) in which wildtype PIK3CA is overexpressed in head and neck epithelium. Although PIK3CA overexpression alone was not sufficient to initiate HNSCC formation, it significantly increased tumor susceptibility in an oral-carcinogenesis mouse model. PIK3CA overexpression in mouse oral epithelium increased tumor invasiveness and metastasis by increasing epithelial-mesenchymal transition and by enriching a cancer stem cell phenotype in tumor epithelial cells. In addition to these epithelial alterations, we also observed marked inflammation in tumor stroma. AKT is a central signaling mediator of the PI3K pathway. However, molecular analysis suggested that progression of PIK3CA-driven HNSCC is facilitated by PDK1 and enhanced TGFβ signaling rather than by AKT. Examination of human HNSCC clinical samples revealed that both PIK3CA and PDK1 protein levels correlated with tumor progression, highlighting the significance of this pathway. In summary, our results offer significant insight into how PIK3CA-overexpression drives HNSCC invasion and metastasis, providing a rationale for targeting PI3K/PDK1 and TGFβ signaling in advanced HNSCC patients with PIK3CA amplification.

[The molecular bypass: an established method for revascularisation of non-operable PAD patients or merely a future vision]

Collateral vessel growth is a physiological process that is not equally pronounced in all people. After the development of a haemodynamically relevant stenosis in vascular systems, blood flow is directed through a collateral circulation to supply ischaemic tissue. This collateral circulation exists on the capillary level and by definition, is not composed of real new vessels. Postnatal vasculogenesis (true neovascularisation) occurs in the adult organism in tumour vascularisation, wound healing, in the endometrium, and in the context of chronic diseases such as rheumatoid arthritis and psoriasis. Reopening of the occluded vessel or use of artificial bypass grafts are the most attractive therapeutic approaches for treating peripheral arterial and coronary artery disease. These strategies have been exhausted in many patients; therefore augmentation of arteriogenesis can be more useful. Arteriogenesis, the promotion of natural collateral growth, is a hot topic in vascular research. Monocytes play a key role in arteriogenesis by "homing" to areas of collateral vessel growth and locally secrete multiple essential growth factors. Furthermore, stem cells of different origins, endothelial progenitor cells or mononuclear cells are currently being used to promote vessel growth. Also, the application of growth factors such as VEGF, MCP-1, GM-CSF have been already used in clinical trials. This review article describes the physiology and pathophysiology of vascular stenoses and their compensation mechanisms. The review also gives an overview of current treatment approaches and new strategies for non-operable PAD patients. The article presents the current cell and growth factor-related studies, as well as results of balloon dilatation and stent implantation or bypass surgery studies for improvement of revascularisation.

Paramediastinal air cyst with traumatic bronchial injury: a rare complication of neonatal resuscitation

Paramediastinal air cysts and pneumatoceles are known complications of chest trauma and mechanical ventilation. After an initial period of enlargement, these lesions tend to resolve completely with conservative management. We present a case of a premature newborn who developed an enlarging paramediastinal air cyst as a result of resuscitation around the time of delivery that ultimately required surgical excision via a right thoracotomy. To our knowledge, this is the first reported case in a neonate.

Peptide neurons in peripheral tissues including the urinary tract: immunohistochemical studies

Using the indirect immunofluorescence technique of Coons and collaborators, neurons containing substance P-, enkephalin-, vasoactive intestinal polypeptide (VIP)--and somatostatin-like immuno-reactivity have been identified in the peripheral nervous system. They have a widespread distribution, particularly in the gastrointestinal and urinary tracts. Whereas part of these peptide containing fibres may belong to sensory neurons, the majority seem to have their origin in peripheral autonomic ganglia, indicating a complex built up of the autonomic nervous system. There is evidence that some noradrenergic neurons contain somatostatin, which may suggest that one neuron can synthesize and store two transmitters. The significance of such neurons, as well as of peripheral peptide neurons in general, remains to be elucidated.

Alterations in growth and branching of Neurospora crassa caused by sub-inhibitory concentrations of antifungal agents

Six antifungal agents at subinhibitory concentrations were used for investigating their ability to affect the growth and branching in Neurospora crassa. Among the antifungals herein used, the azole agent ketoconazole at 0.5 microg/ml inhibited radial growth more than fluconazole at 5.0 microg/ml while amphotericin B at 0.05 microg/ml was more effective than nystatin at 0.05 microg/ml. Morphological alterations in hyphae were observed in the presence of griseofulvin, ketoconazole and terbinafine at the established concentrations. The antifungal agents were more effective on vegetative growth than on conidial germination. Terbinafine markedly reduced growth unit length (GU) by 54.89%, and caused mycelia to become hyperbranched. In all cases, there was a high correlation between hyphal length and number of tips (r > 0.9). All our results showed highly significant differences by ANOVA, (p < 0.001, alpha = 0.05). Considering that the hyphal tip is the main interface between the fungus and its environment/through which enzymes and toxins are secreted and nutrients absorbed, it would not be desirable to obtain a hyperbranched mycelia with inefficient doses of antifungal drugs.