Site-specific genomic integration in mammalian cells mediated by phage phiC31 integrase.

We previously established that the phage phiC31 integrase, a site-specific recombinase, mediates efficient integration in the human cell environment at attB and attP phage attachment sites on extrachromosomal vectors. We show here that phage attP sites inserted at various locations in human and mouse chromosomes serve as efficient targets for precise site-specific integration. Moreover, we characterize native "pseudo" attP sites in the human and mouse genomes that also mediate efficient integrase-mediated integration. These sites have partial sequence identity to attP. Such sites form naturally occurring targets for integration. This phage integrase-mediated reaction represents an effective site-specific integration system for higher cells and may be of value in gene therapy and other chromosome engineering strategies.

Plasmapheresis in the treatment of steroid-resistant focal segmental glomerulosclerosis.

A patient presented with a severe nephrotic syndrome and a renal biopsy consistent with early focal segmental glomerulosclerosis (FSGS). After a year of intensive immunosuppressive therapy proteinuria was unabated and renal function began to deteriorate. Treatment with weekly plasmapheresis combined with moderate doses of prednisone and azathioprine produced a dramatic decrease in proteinuria and serum creatinine. A marked fall in the B-cell population occurred during treatment, as well as an increase both in T-lymphocytes of the mature CD4+ helper/suppressor phenotype and in the immature/cytotoxic CD8+ phenotype. Activation of the immune system during treatment was demonstrated by an increase in the rate of spontaneous proliferation of peripheral blood mononuclear cells and an increase in T-cell expression of the interleukin-2 receptor.

An ominous undulating fetal heart rate pattern.

Three cases of severely compromised fetuses are reported in which a similar FHR tracing was observed: an undulating pattern describing a "sinusoidal" shape, a frequency of 0.5-1 cpm, amplitude of 10-15 bpm, and flattened baseline varying between 60-120 bpm. This pattern appears to differ significantly from the sinusoidal pattern described previously and appears to identify an agonal or pre-agonal fetus that nonetheless may be salvageable and, therefore, requires maximal obstetric intervention.

Sarcoma complicating von Recklinghausen disease in pregnancy.

Several cases of benign enlargment of neurofibromata during pregnancy are reported in the literature. We believe the present case to be the first report of malignant schwannoma occurring in such a tumor during pregnancy. As this case illustrates, malignant sarcomatous change must be carefully considered in such patients. Prompt diagnosis and radical therapy offer the only chance of survival in malignant schwannoma.

Tissue and glomerular deposition of globulin aggregates.

We studied the behavior of AgGG, a model of iCs, in the rat. The clearance of radiolabeled AgGG from the circulation was found to follow first-order kinetics. The t1/2 of the AgGG increased markedly with increases in dose administered, whereas the absolute rate of removal appeared to approach a maximum. The bulk of the AgGG cleared was found in the liver, and less than 1% was found in spleen, lung, or kidney. All these features are typical of the behavior of macromolecules removed from the circulation by the RES. Specific glomerular deposition was studied at various dosages by isolating glomeruli and measuring the fraction of injected aggregate that was trapped. This fraction represented less than 10% of total renal deposits. Moreover, when animals were sacrificed at an interval of 1 t1/2 after the injection of the corresponding dose, the fraction deposited in glomeruli remained constant. The significance of this finding is discussed in relation to the pathogenesis of glomerulonephritis.

The glucose tolerance test as a means of identifying intrauterine growth retardation.

The purpose of this prospective, nonconcurrent study was to determine whether maternal hypoglycemia, as measured by a 3-hour glucose tolerance test, is associated with pregnancies resulting in growth-retarded infants. Our results demonstrate that maternal hypoglycemia is significantly associated with intrauterine growth retardation other than the low birth weight type and that the 3-hour glucose tolerance test is an effective early screening test in detecting pregnancies at risk of fetal growth retardation.

Tubo-ovarian abscess: a retrospective review.

The charts of 160 patients with tubo-ovarian abscesses (TOAs) were reviewed. Patients were divided into two groups according to their response to initial medical therapy. Predictive factors were identified for the two groups. Prognosis was predictable on the basis of extent of disease at diagnosis and the initial response to medical therapy. There was no apparent association between a unilateral TOA and the use of an intrauterine contraceptive device. A minimum pregnancy rate of 8% was observed in patients maintaining reproductive function. No patient with a bilateral TOA conceived. Of all patients admitted to the hospital with TOA, 53% ultimately required surgical therapy. High residual morbidity and/or resultant infertility mandates more aggressive attempts at prevention.

Renal glycosuria due to gentamicin in rabbits.

Gentamicin sulfate was given to rabbits for four weeks in two dosage regimens, either 4 or 8 mg/kg subcutaneously twice a day. Two of the seven animals in each group regained nearly normal renal function after a transient rise in the level of serum creatinine, but the remainder developed severe renal failure leading to the death of all but one of these rabbits. None of the animals showed significant hyperglycemia, buy glycosuria appeared in all and was significantly correlated with the extent of renal damage. These findings demonstrate gentamicin-induced derangement of proximal tubular function and thus amplify the previously demonstrated histologic changes due to the drug. When the drug was administered twice daily, there was marked nephrotoxicity in rabbits given dosages of gentamicin only slightly higher than those employed clinically.