One-Dimensional NMR Imaging of High-Temperature First-Drying in Monolithics.

In this study a specialized high-temperature nuclear magnetic resonance (NMR) setup is presented for measuring free moisture in monolithic refractory castables during one-sided heating (100-300 °C). This setup makes use of a high thermal-stability Birdcage-coil for measuring the quantitative moisture content at high-temperatures, while also utilizing a mini-coil for calibrating transverse relaxation changes, as a function of temperature and hydration state, taking place in the sample throughout a drying experiment. We employ a high-temperature correction scheme that calibrates the effects of rising temperatures on the NMR signal. With this configuration, we can non-destructively measure moisture and temperature profiles continuously and achieve a spatial resolution of 2-3 mm for samples as long as 74 mm. After applying the NMR correction, we can extract information about the physical and chemical components of water as they are released from the porous matrix during first heat up. As a model material, we demonstrate the capability of our setup with a conventional castable after it has been cast and cured for 48 h.

An infant with deletion of the distal long arm of chromosome 15 (q26.1----qter) and loss of insulin-like growth factor 1 receptor gene.

We report on an infant with a previously undescribed chromosome 15 deletion (q26.1----qter) and compare the clinical findings with those of 7 reported patients with deletions of distal 15q, as well as ring chromosome 15 syndrome patients. Most of the patients with deletions of distal 15q, including our patient, have intrauterine growth retardation (IUGR), microcephaly, abnormal face and ears, micrognathia, highly arched palate, renal abnormalities, lung hypoplasia, failure to thrive, and developmental delay/mental retardation. Several genes have been assigned to the 15q25----qter region, including insulin-like growth factor 1 receptor (IGF1R). DNA analysis from our patient documented the loss of one IGF1R gene copy. Our study further localizes the IGF1R gene distal to the 15q26.1 band. It is interesting to speculate that the severe IUGR and postnatal growth deficiency of our patient and other patients with similar chromosome 15 deletions are related to the loss of an IGF1R gene copy which may lead to an abnormal number and/or structure of the receptors.

Occurrence of congenital abnormalities of kidney and urinary tract in 13,775 autopsies.

Records of 13,775 consecutive autopsies were reviewed to determine the incidence of renal and urinary tract abnormalities. A total of 636 abnormalities were found in 427 autopsies, with an overall frequency of 4.6 percent and 9.5 percent in males under eighteen years old. The kidney was involved in 45.1 percent, ureters 29.1 percent, renal vessels 12.4 percent, urethra 5.3 percent, bladder 4.8 percent, and fistulas 3.3 percent. We conclude: (1) Although it is difficult to assess accurate incidence rates of renal and urinary tract abnormalities, this study notes the frequency of these abnormalities in autopsies. (2) The markedly higher incidence in the younger age group indicates the high mortality of many of these anomalies. (3) Over 85 percent of abnormalities are in the upper urinary tract, which are more likely to produce end-stage renal disease and a higher mortality. (4) These observations indicate the importance of further research to establish methodology for early detection of congenital abnormalities of the kidney and urinary tract.

Gitelman's syndrome (familial hypokalemia-hypomagnesemia).

Gitelman's syndrome (GS) is a heritable renal disorder characterized by hypomagnesemia, hypokalemia and hypocalciuria, and distinct from Bartter's syndrome (BS). As compared to those with BS, patients with GS present at an older age, and they have a milder clinical picture, normal or slightly decreased concentrating ability, reduced urinary excretion of calcium, and permanently decreased serum magnesium level. GS is caused by defective NaCl transport in the distal convoluted tubule, and linked to the gene encoding the thiazide sensitive Na-Cl-cotransporter located on chromosome 16q. Patients with BS, on the other hand, have mutations in the transporters in the thick ascending loop of Henle (NKCC2, ROMK, and C1C-Kb). Treatment of GS consists of magnesium salt replacement. Long term prognosis in terms of maintaining growth, preserving renal function and life expectancy is excellent.

Extra-adrenal pheochromocytoma.

Extra-adrenal pheochromocytomas, or gangliomas, develop in the paraganglion chromaffin cells of the sympathetic nervous system. They account for 10% of all pheochromocytomas in adults and 30-40% in children. These tumors are usually larger than their adrenal counterpart. The most common site of extra-adrenal phenochromocytomas is the para-adrenal area, but they also occur at the aortic bifurcation, chest, inferior mesenteric and iliac arteries, bladder, heart and brain. In this report, we describe a 13-year-old girl with a pheochromocytoma along the course of the left ureter, a finding which to our knowledge was previously described only once. Clinical presentation, diagnosis, and treatment are similar to adrenal tumors. Patients should be closely monitored with serum and urine catecholamine determination and MIBG scan to detect any recurrence or distant metastasis. Prognosis is usually good if the tumor is detected early to avoid major complications related to catecholamine excess.

Renal disease in Lebanese children and adolescents. Findings in 118 consecutive percutaneous renal biopsies.

One hundred and eighteen consecutive percutaneous renal biopsies performed on 104 Lebanese children and adolescents at the American University of Beirut Medical Center over a period of six years were reviewed retrospectively. These patients represent the great majority of renal biopsies performed on Lebanese children and adolescents during that period. The kidney was localized with the help of an IVP or ultrasound and the procedure was performed without direct guidance. Adequate renal tissue was obtained in 112 biopsies with a success rate of 95.0%. The procedure appears to be safe in children. The renal diseases identified and their incidence is comparable to those reported in the literature. Acute nephropathy was seen in 9.6% of the patients, primary nephrosis in 45.0% and secondary glomerular disease in 14.6%. Tubulointerstitial disease, metabolic and hereditary diseases and end-stage renal diseases were found in 7.7%, 6.7%, and 5.8% of patients respectively. Some previously unreported conditions were identified.

Kidney abnormalities in Hajdu-Cheney syndrome.

We report a 14-year-old boy from Saudi Arabia with the Hajdu-Cheney syndrome who also had bilateral hypoplastic kidneys and chronic renal failure. This report, along with others in the literature, suggest that renal abnormalities, including cystic disease, vesico-ureteral reflux, glomerulonephritis, chronic renal failure, and hypertension, may be an integral part of this syndrome. Recognizing this fact, may help in the early diagnosis, prevention, and treatment of renal failure in these patients.

Focal sclerosing glomerulonephritis in a child with Laurence-Moon-Biedl syndrome.

We report a 6-year-old white male with Laurence-Moon-Biedl syndrome and focal sclerosing glomerulonephritis (FSGN). To our knowledge, FSGN has not been reported previously in patients with this syndrome. We wish to alert the clinician to the wide variety of renal abnormalities that can be seen in patients with this rare, autosomal recessive disorder.

Reliability of ultrasound in the prenatal diagnosis of urinary tract abnormalities.

To investigate the ability of ultrasonography to detect urinary tract abnormalities prenatally, we reviewed the records of 26 pregnancies diagnosed by prenatal ultrasound to have urinary tract anomalies. We compared the prenatal diagnoses with postnatal renal and urinary tract pathology. This comparison showed different degrees of agreement for different prenatal diagnoses (2 individuals had more than one diagnosis): 4 of 8 for multicystic kidneys, 1 of 1 for polycystic kidney disease, 1 of 2 for renal agenesis, 6 of 7 for ureteropelvic junction obstruction, 1 of 3 for posterior urethral valves, 4 of 5 for no pathology noted, and 2 of 2 for other abnormalities. Prenatal diagnosis and postnatal findings were in agreement in 68% of cases. Varying levels of diagnostic reliability should be considered when managing pregnancies complicated by fetal urinary tract abnormalities and subsequent postnatal evaluation and diagnosis. Further efforts are needed to improve on the techniques and reliability of prenatal diagnosis of urinary tract abnormalities.