Does the T-locus in the mouse include ribosomal DNA?

We studied in 130 parturients during childbirth the effects of general anaesthesia by Alfatesine on the state of the foetus at birth. The examinations took into account the APGAR score, blood gas analysis, pH, bases excess in the umbilical artery and vein and the foetal EEG. The subjects are divided into three groups: prophylactic caesarians, extractions during labor in the absence of any foetal distress and extractions for reasons of acute or chronic foetal distress. The results are evaluated in comparison with the same tests conducted on a series of newborn infants in normal conditions and without anaesthesia. The APGAR score is hardly affected by the Alfatesine; the EEG is perturbed (but without any clinical manifestations) during the two hours following delivery. However, theses modifications are less pronounced than those observed with barbiturates. The study of blood gases and pH shows lower values under anaesthesia than without.     

Histopathologic spectrum of vaginal adenosis and related changes in stilbestrol-exposed females

A total of 98 colposcopically directed biopsies were obtained from the vagina, cervix, and cervicovaginal ridge (hood) of 80 young women believed to have had intrauterine exposure to stilbestrol (DES). Specific investigation of the patient's medical records corroborated the history of maternal stilbestrol administration in 36 patients (45%), while in the remainder the drug history was regarded as presumptive since medical records were unavailable for review. The findings did not differ significantly in those biopsies taken from patients with confirmed or presumptive drug histories. Histologic evidence of vaginal adenosis was detected in vaginal biopsies from 43 patients. In 30 cases (70%) benign Müllerian-type glandular epithelium was in the superficial vaginal wall, residing on the mucosal surface and/or in the lamina propria. The glandular epithelium predominantly was of endocervical type, but in six instances it resembled endometrial or fallopian tubal epithelium. The glands were accompanied by varying degrees of squamous metaplasia in 22 cases. When extensive the metaplasia produced transformation zones similar to those seen in the normal cervix. Vaginal biopsies of adenosis from the other 13 patients (30%) revealed squamous metaplasia without demonstrable glands due to complete transformation of all antecedent glandular epithelium by squamous metaplasia. Our studies indicate that squamous metaplasia is a component of major importance in the natural history of adenosis and that the concept of adenosis should be broadened to include those examples comprised exclusively of metaplastic epithelium. In such examples metaplasia is identified by the immaturity and poor glycogenation of the squamous cells and their accompanying squamous pegs which often contain residual gland openings or squamous "eddies." Similar findings were present in biopsies of seven cervicovaginal ridges and in cervical biopsies from 37 patients, except for the absence of endometrial or tubal type glands in the latter site. Although no adenocarcinomas were detected, six patients had squamous dysplasia of the vagina and/or cervix. In no case were premalignant or dysplastic changes of glandular cells found. Our findings support the thesis that stilbestrol-associated adenosis represents anomalous embryologic localization of the original squamocolumnar junction in the vagina rather than in the cervix. It is closely related to so-called cervical "erosions." The development of squamous metaplasia accounts for modifications in the clinical and histologic appearances by producing transformation zones which then may be subject to the same oncogenic stimuli for squamous neoplasia as are their counterparts in the cervix.     

Developmental specificity and evolution of the acid phosphatase isozymes of Triticum aestivum and its progenitor species

The tissue and developmental specificities of the acid phosphatase (ACPH) isozymes of Triticum aestivum and its progenitor species T. turgidum and T. tauschii have been determined and compared using the zymogram technique. Tissue and/or developmental variation in relative staining intensity, suggestive of variation in the quantity of active enzyme present, was observed for each of the seven major isozymes expressed. Isozymes homologous to each of the major isozymes of the hexaploid were detected in one or the other of the progenitor species. No difference in the pattern of developmental or tissue specificity was observed between the species for any isozyme. However, ACPH-4, encoded by ACph4, a structural gene linked to chromosome 4A, differs in electrophoretic mobility between T. aestivum and T. turgidum, indicating that divergence has occurred between these species at the Acph4 locus since the origin of the hexaploid. The molecular weight of each of five ACPH isozymes of the hexaploid was determined to be approximately 58,000. This finding, plus the results of the developmental study and the earlier demonstration that the structural genes for six isozymes (includinomosomes, provides evidence in support of the suggestion that the ACPH structural genes of hexaploid wheat are homoeologous related.     

Stereochemical requirements for intercalation of platinum complexes into double-stranded DNA's

The complexes 1,10-phenanthrolineethylenediamineplatinum(II) and 2,2'-bipyridineethylenediamineplatinum(II) have a planar, aromatic ligand system that facilitates intercalation, as shown by their ability to unwind closed circular duplex DNA. Nonbonded steric interactions can rotate the pryidine ligands out of the coordination plane in bis(pyridine)ethylenediamineplatinum(II), thus preventing intercalation. Fiber x-ray diffraction patterns of the two metallointeracalators indicate that the binding is governed by the neighbor exclusion principle.     

Effect of charcoal-broiled beef on phenacetin metabolism in man

When charcoal-broiled beef was fed to human volunteers, who were then given phenacetin orally, the concentration of phenacetin in the plasma was lowered, but its half-life in the plasma was not changed. The data suggest that feeding charcoal-broiled beef enhances the metabolism of orally administered phenacetin in the intestine or during its first pass through the liver, or both.     

Identification and quantification of mineral precipitation in Fe0 filings from a column study

Thermogravimetric analysis (TGA) combined with X-ray diffraction (XRD) was used to identify mineral phases and determine corrosion rates of granular iron samples from a 2-yr field column study. Similar to other studies, goethite, magnetite, aragonite, and calcite were found to be the major precipitated minerals, with Fe2(OH)2CO3 and green rust as minor phases. Based on TGA-mass spectrometry (MS) analysis, Fe0 corrodes at rates of 0.5-6.1 mmol kg(-1) d(-1) in the high NO3- (up to 13.5 mM) groundwater; this rate is significantly higher than previously reported. Porosity reduction was 40.6%-45.1% for the inlet sand/Fe0 interface and 7.4%-25.6% for effluent samples of two test columns. Normalized for treatment volumes, porosity loss values are consistent with studies that use high levels of SO4(2-) but are higher than those using low levels of corrosive species. Aqueous mass balance calculations yield corrosion rates similar to the TGA-MS method, providing an alternative to coring and mineralogical analysis. A severely corroded iron sample from the column simulating a 17-yr treatment throughput showed >75% porosity loss. Extensive porosity loss due to high levels of corrosive species in groundwater will have significant impact on long-term performance of permeable reactive barriers.