Pulsatile nanofluid flow with variable pressure gradient and heat transfer in wavy channel.

This research contributes to the comprehension of nanofluid behaviour through a wavy channel, emphasizing the significance of considering diverse influences in the modelling process. The study explores the collective influence of pressure gradient variation, magnetic field, porosity, channel waviness, nanoparticle concentration, and heat transfer on nano-blood flow in a two-dimensional wavy channel. In contrast to prior research assuming a constant pulsatile pressure gradient during channel waviness, this innovative study introduces a variable pressure gradient, significantly influencing several associated parameters. The mathematical model characterizing nano-blood flow in a horizontally wavy channel is solved using the perturbation technique. Analytical solutions for fundamental variables such as stream function, velocity, wall shear stress, pressure gradient, and temperature are visually depicted across different physical parameters values. The findings obtained for differing parameter values in the given problem demonstrate a significant influence of the amplitude ratio parameter of channel waviness, Hartmann number of the magnetic field, permeability parameter of the porous medium, volume fraction of nanoparticles, radiation parameter, Prandtl number, and the suction/injection parameter on the flow dynamics. The simulations provide valuable insights into the decrease in velocity with increasing magnetic field and its increase with higher permeability. Additionally, the temperature is observed to escalate with a rising nanoparticle volume fraction and radiation parameter, while it declines with increasing Prandtl number.

ROBERTS SYNDROME: CLINICAL AND CYTOGENETIC STUDIES IN 8 EGYPTIAN PATIENTS AND MOLECULAR STUDIES IN 4 PATIENTS WITH GENOTYPE/PHENOTYPE CORRELATION.

The Roberts syndrome (RBS) is a rare autosomal recessive disorder caused by mutation in ESCO2 gene. Among over 150 reported international cases, 16 cases are Egyptian including the presently reported patients. The current study reports 8 new Egyptian patients from 7 unrelated consanguineous families investigating clinical phenotype as well as cytogenetic changes in all cases and mutational spectrum in 4 cases. Clinical, orodental, cytogenetic and molecular studies were done to investigate genotype/phenotype correlation. Evaluation of the studied 8 patients showed that they all exhibited the main limb and craniofacial features of Roberts syndrome. Cytogenetic studies including centromeric separation and puffing by Giemsa and DAPI stains and for the first time in Egypt analysis for premature centromeric division by FISH showed consistent centromeric separation in all studied cases. Molecular studies of 4 available patients showed that they all have ESCO2 gene mutation. We conclude that RBS has a well-defined clinical spectrum. The cytogenetic changes are due to sister chromatid cohesion defects which lead to mitotic dysfunction. We confirmed previous results of lack of genotype/phenotype correlation. We also confirmed that the severity of limb malformation correlates with craniofacial manifestations. We recommend detailed evaluation of orodental changes for further definition of the phenotype and for proper patient management. We emphasize the need for further studies for the frequency of premature centromeric separation by FISH as a possible indicator of phenotypic severity.

Slip Effects on Peristaltic Transport of a Particle-Fluid Suspension in a Planar Channel.

Peristaltic pumping induced by a sinusoidal traveling wave in the walls of a two-dimensional channel filled with a viscous incompressible fluid mixed with rigid spherical particles is investigated theoretically taking the slip effect on the wall into account. A perturbation solution is obtained which satisfies the momentum equations for the case in which amplitude ratio (wave amplitude/channel half width) is small. The analysis has been carried out by duly accounting for the nonlinear convective acceleration terms and the slip condition for the fluid part on the wavy wall. The governing equations are developed up to the second order of the amplitude ratio. The zeroth-order terms yield the Poiseuille flow and the first-order terms give the Orr-Sommerfeld equation. The results show that the slip conditions have significant effect within certain range of concentration. The phenomenon of reflux (the mean flow reversal) is discussed under slip conditions. It is found that the critical reflux pressure is lower for the particle-fluid suspension than for the particle-free fluid and is affected by slip condition. A motivation of the present analysis has been the hope that such theory of two-phase flow process under slip condition is very useful in understanding the role of peristaltic muscular contraction in transporting biofluid behaving like a particle-fluid mixture. Also the theory is important to the engineering applications of pumping solid-fluid mixture by peristalsis.

Structure-directing roles and interactions of fluoride and organocations with siliceous zeolite frameworks.

Interactions of fluoride anions and organocations with crystalline silicate frameworks are shown to depend subtly on the architectures of the organic species, which significantly influence the crystalline structures that result. One- and two-dimensional (2D) (1)H, (19)F, and (29)Si nuclear magnetic resonance (NMR) spectroscopy measurements establish distinct intermolecular interactions among F(-) anions, imidazolium structure-directing agents (SDA(+)), and crystalline silicate frameworks for as-synthesized siliceous zeolites ITW and MTT. Different types and positions of hydrophobic alkyl ligands on the imidazolium SDA(+) species under otherwise identical zeolite synthesis compositions and conditions lead to significantly different interactions between the F(-) and SDA(+) ions and the respective silicate frameworks. For as-synthesized zeolite ITW, F(-) anions are established to reside in the double-four-ring (D4R) cages and interact strongly and selectively with D4R silicate framework sites, as manifested by their strong (19)F-(29)Si dipolar couplings. By comparison, for as-synthesized zeolite MTT, F(-) anions reside within the 10-ring channels and interact relatively weakly with the silicate framework as ion pairs with the SDA(+) ions. Such differences manifest the importance of interactions between the imidazolium and F(-) ions, which account for their structure-directing influences on the topologies of the resulting silicate frameworks. Furthermore, 2D (29)Si{(29)Si} double-quantum NMR measurements establish (29)Si-O-(29)Si site connectivities within the as-synthesized zeolites ITW and MTT that, in conjunction with synchrotron X-ray diffraction analyses, establish insights on complicated order and disorder within their framework structures.

A new multiple congenital anomaly, mental retardation syndrome with preaxial brachydactyly, hyperphalangism, deafness and orodental anomalies.

We report on a child with a 'new' syndrome characterized by multiple congenital anomalies, mental retardation, sensorineural deafness, talon cusps of upper central incisors, growth retardation, bilateral symmetrical digital anomalies mainly in the form of preaxial brachydactyly and hyperphalangism of digits I-III. Because he had a similarly affected brother and his parents were cousins we suggest autosomal recessive inheritance, X-linked recessive inheritance cannot be excluded. Differential diagnosis from other syndromes with preaxial brachydactyly and hyperphalangism is presented.

GAPO syndrome: first Egyptian case with ultrastructural changes in the gingiva.

We report on a 3-year-old boy with growth retardation, alopecia, pseudoanodontia, and optic atrophy. This is the 18th known and the first Egyptian case of GAPO syndrome. Electron microscopic examination of gingival biopsy showed excessive collagen fibres and endothelial vacuolisation, suggesting involvement of extracellular pathological collagenosis.

Encephalocraniocutaneous lipomatosis and the Proteus syndrome: distinct entities with overlapping manifestations.

We have studied three children with cutaneous (epidermal nevi), subcutaneous (lipomas, plantar skin thickening), vascular (hemangioma, lymphangioma), skeletal (osteoma, exostosis, localized hypertrophy), and neurological (hydrocephaly, lissencephaly, partial agenesis of the corpus callosum) developmental defects associated with the Proteus syndrome and related hamartoneoplastic conditions. We compared our findings in these three patients with those of 50 others with Proteus syndrome and nine with encephalocraniocutaneous lipomatosis (ECCL) reported in the literature. We found that Proteus syndrome and ECCL have distinct identities even though some clinical manifestations are shared by both and a few patients have manifestations of both conditions.

A common anti-DNA antibody idiotype and anti-phospholipid antibodies in sera from patients with schistosomiasis and filariasis with and without nephritis.

The serum concentration of a public idiotype (16/6 ID), originally identified on a human hybridoma-derived monoclonal anti-DNA antibody, was raised in patients with S. mansoni and filariasis with or without nephritis, compared to patients with S. haematobium (in which nephritis does not occur) or idiopathic nephritis not associated with infection. There was no significant difference in 16/6 ID levels between patients with or without renal disease, whether associated with S. mansoni or filarial infection. The 16/6 ID-positive antibodies did not bind to native or denatured DNA, using competitive fluid-phase inhibition studies. Anti-cardiolipin antibody (ACA) concentration was increased in patients with either S. mansoni or filarial infection. In filariasis, both IgG and IgM ACA isotypes were elevated, irrespective of the presence of nephritis. In S. mansoni infection, IgA ACA were limited to patients with renal disease, and IgG ACA isotype to patients without overt nephritis. Both isotypes of anti-cardiolipin antibody correlated with levels of the 16/6 ID in patients with S. mansoni or filariasis. The 16/6 idiotype was therefore a feature of chronic helminthic infection, but was not related to anti-DNA antibody levels or specificity. The occurrence of nephritis as a complication of these infections was not related to the prevalence of the 16/6 idiotype.

Glycosylated proteins in diabetic nephropathy.

This study was carried out on 55 diabetic patients, 20 of whom had diabetic nephropathy, and 10 controls. Glycosylated haemoglobin, glycosylated serum protein, glucoprotein, serum protein electrophoresis, blood urea, serum creatinine and beta 2-microglobulin were measured. A significant increase of glucoprotein was observed in patients with diabetic nephropathy. No correlation was found between glycosylated serum protein and glycosylated haemoglobin and duration of diabetes. Glycosylated serum protein showed a positive correlation with beta 2-microglobulin, indicating a link between renal involvement and the rise in glycosylated serum protein. Whether there is a pathogenic relation between glycosylated serum protein and the development of nephropathy awaits further evidence.

The long-term outcome of idiopathic membranous nephropathy.

Thirty-five consecutive patients with renal biopsy appearances of idiopathic membranous nephropathy, who were initially studied between 1960 and 1969, were reevaluated in 1979 to determine (a) the long-term outcome of idiopathic membranous nephropathy, and (b) whether any clinical or biopsy features at onset would permit prediction of long-term outcome. After fifteen years, actuarial analysis showed that approximately half the patients would be in remission; the rest dead or on dialysis/transplantation programs. Entry into renal failure, in those who ran this course, started at three years after diagnosis and continued steadily for at least another ten years. Likewise, remission was seen as early as one year from onset, but patients were still going into remission after thirteen years of proteinuria. No feature in the glomeruli predicted outcome, but interstitial and vascular changes were seen more frequently in those whose disease persisted or worsened. No onset feature predicted a poor outcome reliably, but younger patients did better than older, and all three children with initial macroscopic hematuria went into remission.

Acute renal failure in the 1973 Middle East war--experience of a specialized base hospital: effect of the site of injury.

All battle casualties admitted to a specialized base hospital were surveyed for early signs of acute renal failure (ARF), and diuresis was induced in high-risk subjects. Sixty of 1.147 cases developed ARF. Statistical analysis showed that ARF was more frequently observed with multiple injuries, as well as with single injuries of the abdomen, proximal lower limb, and the head and cervical spine. These were therefore considered as critical sites of injury. The relation of urine output, incidence of septic complications, and mortality rate to the site(s) and multiplicity of trauma is discussed, along with the probable mechanism(s) of ARF following each of the critical injuries.

Renal amyloidosis and schistosomiasis.

A retrospective study of 60 renal biopsies obtained from nephrotic subjects with schistosomiasis showed amyloid deposits in 10 cases. Distribution was usually segmental, mainly mesangial and overlapped with the conventional mesangio-proliferative lesions of schistosomiasis. The invariable clinical presentation was proteinuria with generalized oedema of insidious onset and a slowly progressive or intermittent course. Differences from conventional schistosomal nephropathy are described. Response to anti-schistosomal treatment was very poor. Repeat renal biopsies showed no regression of the lesions. The possible links between schistosomiasis and amyloidosis are discussed and causes of amyloid deposition suggested.