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يعالج البحث الجريان غير المنتظم في القنوات المكشوفة باستعمال طريقة Runge-Kutta العددية في حل المعادلة التفاضلية الأساسية للجريان. ثم يستنتج البحث معادلات مبسطة عديمة الوحدات من نتائج حل المعادلة التفاضلية باستعمال الحاسوب حيث تساعد هذه المعادلات على تصميم ودراسة الجريانات في القنوات ذات المقطع المنتظم دون العودة إلى تكامل المعادلة التفاضلية العامة.

Previous studies, using parenteral administration of antigen in lipid vesicles, have indicated a possible role for vesicle size in determining the Th1/Th2 bias of the resulting immune response. We have also demonstrated that the incorporation of bile salts into lipid vesicles (bilosomes) allows successful induction of mucosal and systemic immunity via the oral route. The following study was therefore carried out to determine whether size could also influence the Th1/Th2 bias in the immune response to bilosome entrapped influenza A antigen containing haemagglutinin administered by the oral route in the mouse and whether this could influence the disease process in the classical ferret model of disease. Consequently we produced two formulations of influenza A antigen entrapped in bilosomes: BV3 which contained a single population (range 10-100 nm, Z-average diameter 250 nm) and BV which had two populations (60-350 and 400-2,500 nm, Z-average 980 nm). Following oral vaccination of BALB/c mice, BV was found to generate an immune response that had a significantly greater Th1 bias than BV3 as measured by serum IgG2a production and antigen-induced spleen cell IFN-gamma production. In the traditional infection challenge model (ferrets) vaccination with BV (large) vesicles resulted in greater protection in terms of symptom-score and a higher responder number. However, both oral vaccine formulations were an improvement on intramuscular administration in terms of higher antibody production, lower temperatures, and reduced symptoms over time, post-infection. The results presented here demonstrate that oral vaccine formulations can be physically modified to manipulate resultant immune responses following vaccination and consequently can be designed to enhance the effectiveness of candidate vaccine antigens.

The emergence of antibiotic resistant bacterial strains is a growing problem and is an important concern for patients, physicians, healthcare managers, and policymakers as it results in poorer health and economic outcomes. This has led to an urgent global call for new antimicrobial drugs, particularly from natural resources. We have been studying the antimicrobial properties of the inner leaf gel component of Aloe barbadensis Miller and have used a number of different, simple in vitro assays to establish a scientific basis for the potential use of Aloe vera on a range of clinically relevant bacteria. The bacteria used include Shigella flexneri, Methicillin-Resistant Staphylococcus aureus (MRSA), Enterobacter cloacae and Enterococcus bovis. In this paper, we compare standard methods recommended by the Clinical and Laboratory Standards Institute (CLSI) with a microtitre assay using a metabolic colour indicator Alamar blue. All the techniques described have shown that Aloe vera has an antimicrobial effect, however, the microtitre assay enables high throughput screening, under similar conditions and is less wasteful of plant material.

Protein antigens administered via the oral route are exposed to a hostile environment in the gastrointestinal tract, consisting of digestive enzymes and a range of pH (1-7.5). Using a delivery system can afford protection to entrapped components against degradation and permit delivery of antigen to the cells responsible for generating local and systemic immune responses. In this comparative study, mice were immunised orally with tetanus toxoid (40 or 200 microg dose/mouse, four doses in total) entrapped in non-ionic surfactant vesicles formulated with bile salts (bilosomes). The higher entrapped dose (BV-TT, 200 microg) induced IgG1 by study week 3 to similar levels to those observed with subcutaneous un-entrapped TT at the lower (<50 microg) dose. However, both bilosome formulations (BV-TT, low, and high doses), though not un-entrapped TT, caused a rise in the numbers of IgA positive plasma cells observed in the small intestine, primarily in the first 15 cm of the small intestine.

Chiari malformation Type I (CM-I), a condition defined by caudal descent of the cerebellar tonsils through the foramen magnum, is generally considered a congenital lesion. Several authors, however, have described an acquired form that appears identical to the congenital lesion on neuroimages. The most commonly reported cause of an acquired CM-I is cerebrospinal fluid diversion through a lumboperitoneal shunt. In this paper, the authors report the case of a patient in whom an acquired CM-I developed in association with a supratentorial arteriovenous malformation (AVM) of the brain. Development of the acquired CM was documented on serial magnetic resonance images. Moreover, the CM was seen to originate and worsen in concert with the clinicoradiological progression of the AVM. The underlying mechanism responsible for the acquired CM in this case is thought to be a high-flow venopathy of the transverse and sigmoid sinuses causing occlusion on the right and redirection of venous outflow into posterior fossa veins, with consequent venous congestion and swelling of the posterior fossa structures.

Aloe barbadensis Miller (or Aloe vera) has widespread use in health products, and despite numerous reports on the whole plant, little work has been performed on the inner gel, which has been used extensively in these products. This report describes the in vitro susceptibilities of two bacteria to this component.