Enrichment of the spindle fiber attachments from mouse liver cell nuclei

Spindle fiber attachments (SFAs) were enriched in a fraction of nuclei isolated from mouse livers. The enrichment method combines sonication, treatment with 2 mol/L NaCl and high speed centrifugation. SFA was enriched 27-fold on the average (n = 4) when measured by radioimmunoassay. The basic method offers opportunities for further increases of yield and for the enrichment of SFA of other vertebrates.

Progressively restricted expression of a homeo box gene within the aboral ectoderm of developing sea urchin embryos

A homeo box-containing gene, Hbox1 is expressed in an unusual and highly conserved spatial pattern in embryos of two different species of sea urchin, Tripneustes gratilla and Strongylocentrotus purpuratus. Hybridization in situ shows that this mRNA accumulates initially throughout the aboral ectoderm; however, between blastula and pluteus stages, the region containing Hbox1 mRNA retracts gradually until only a small area around the vertex is labeled in pluteus larvae. Aboral ectoderm appears cytologically uniform and also accumulates uniform levels of other tissue-specific mRNAs. Therefore, the Hbox1 pattern reveals a previously unsuspected heterogeneity of aboral ectoderm cells and a polarity within this tissue. In S. purpuratus, the Hbox1 gene product probably is not involved in initial specification of cell fate, as this message does not achieve a significant fraction of its peak abundance until almost hatching blastula stage, well after the time aboral ectoderm cells have initiated a tissue-specific program of gene expression. RNA blot and RNase protection analyses revealed low levels of Hbox1 mRNA in all adult tissues examined. However, this message was not detectable in mature eggs, suggesting that the Hbox1 gene does not have a maternal function. In addition to highly conserved spatial and temporal patterns of expression, the homeo box genes of these two urchin species also are conserved highly in sequences outside the homeo domain, despite the divergence of these two species (30-45 my). Two notable features of the protein shared with several vertebrate homeo proteins are a short conserved sequence encoded by an exon upstream of that encoding the homeo domain and a large region of high serine and proline content.

Stage- and tissue-specific expression of two homeo box genes in sea urchin embryos and adults

We report the isolation of two different homeo box genes, HB3 and HB4, from the Hawaiian sea urchin Tripneustes gratilla. DNA sequencing revealed a definitive Antennapedia (Antp) class homeo box in each gene. Southern transfer hybridizations showed the genes to be single-copy. A 5.7-kb transcript of the HB3 gene was found in ovary, testis, small intestine and gastrula poly(A)+ RNA. The HB4 gene produces three transcripts. A 3.7-kb and a 4.4-kb transcript are expressed during embryogenesis. A 3.5-kb transcript appears in each of the adult tissues studied. The HB4 gene appears to be the sea urchin cognate of the Drosophila infrabdominal-7 (iab-7) gene, the mouse Hox 1.7 and Hox 3.2 genes and the Xenopus X1Hbox 6 gene. An examination of Antp class homeo box genes in deuterostomes indicates that a chromosomal duplication has taken place in the evolutionary line leading to the vertebrates after the divergence of the echinoderms. Thus, the sea urchin represents the primitive condition.

Successful replantation in ten-digit complete amputations

The authors report a case of successful replantation of all fingers in a ten-finger complete amputation. Among the factors responsible for the successful outcome were an adequate number of microsurgically-trained resident surgeons and staff, good organization and supervision by senior staff, emphasis on precision and perseverance in the operative procedures, and postoperative management. Follow-up is 15 months, and the patient now has a pair of functionally and cosmetically good hands.

Involvement of a nucleolar component, perichromonucleolin, in the condensation and decondensation of chromosomes

A component of the nucleolar material, perichromonucleolin (PCN), was identified by a specific antiserum against nucleoli obtained from a scleroderma patient. The distribution and changes of PCN during the mitotic cycle were followed using this antiserum and indirect immunofluorescence microscopy. Based upon the behavior of PCN during mitosis, it could be differentiated into chromosomal and nonchromosomal portions. During prophase the former gradually associates with the surface of the condensing chromosomes and forms the coat or pellicle around the metaphase and anaphase chromosomes. This pellicle PCN is carried by the anaphase chromosomes to the daughter nuclei. During the time from telophase to interphase, the pellicle PCN dissociates from the decondensing chromosomes and is incorporated into the new nucleoli. The nonchromosomal PCN, after the breakdown of the nuclear membrane, distributes in the cytoplasmic region around the condensed chromosomes and diffuses into the cytoplasm during anaphase. Preliminary biochemical analysis by immunoblotting showed that the PCN consists of two main proteins with molecular masses of 36 kDa and 30 kDa.

Anatomical analysis of the cause of skin necrosis of the great toe after transplantation of the great toe nail flap

Necrosis of skin on the medial side of the great toe has been a significant complication of the great toe nail flap. To investigate the reason for this, a study of the blood supply of the medial side of the great toe was carried out on 55 feet with the injection of red latex into the arteries and on 13 vascular cast specimens. It was found that, after the blood vessels from the plantar and dorsal sides of the great toe are severed during the operation, the skin of the medial side of the great toe is mainly supplied by the medial vascular network at the head of the first metatarsal bone. It is clear that the blood supply from this network may sometimes be insufficient to nourish the skin. It is suggested that the operative incision should be changed so as to increase the blood supply to the medial vascular network which may decrease the incidence of skin necrosis.

Nonoperative treatment of Hirschsprung's disease: a new approach

The approach of the combined traditional Chinese and modern medicinal treatment of Hirschsprung's disease has been applied in 90 cases. Long-term follow-up showed satisfactory results. Of these, 55 cases with a typical history, plus a positive ACHE and x-ray were selected for analysis and discussion, making an over all rate of 78.18%. This treatment is particularly useful for those babies under 1 year of age with a short narrow segment of the rectum. In addition, it would be a good trial procedure for those babies over 1 year old with mild symptoms and the narrow segment just beyond the sigmoidorectal junction.

Plasma levels of antiprogestin RU 486 following oral administration to non-pregnant and early pregnant women

RU 486 is a synthetic steroid which acts as an antiprogestin at the receptor level. The clinical usefulness of the compound for menstrual regulation and termination of early pregnancy is currently being evaluated. The aim of the present study was to determine the plasma levels of RU 486 following the oral administration of the compound to 42 pregnant and 10 non-pregnant women. The levels of RU 486 were measured by a radioimmunoassay method which uses chromatography on Sephadex LH 20 columns. The identity of the compound assayed as RU 486 was confirmed, but the presence of small amounts of two highly cross-reacting metabolites (monodemethyl and didemethyl RU 486) in the analyzed fractions could not be excluded. Following the ingestion of a single tablet containing 25 and 50 mg of the compound, a peak plasma value of approximately 3.5 to 4.0 mumol/l in both the pregnant and non-pregnant subjects was reached one to two hours later. The half-lives of elimination were about 20 hours in both the pregnant and the non-pregnant women. Following the repeated oral administration of 50, 100 or 200 mg of RU 486 daily for four days, maximum plasma levels of 2.9, 4.5 and 5.4 mumol/l, respectively, were found. Thus, the increase in plasma levels was not directly proportional to the increase in the dose. No accumulation of RU 486 in the plasma was found, even when the duration of treatment was prolonged to six days. The data partly explain the reported lack of relation between ingested dose and frequency of induced abortion and they may be useful for designing future studies on the use of compound to prevent implantation, induce menstruation or terminate an early pregnancy.

The use of immunoblotting and immunoprecipitation of (U) small nuclear ribonucleoproteins in the analysis of sera of patients with mixed connective tissue disease and systemic lupus erythematosus. A cross-sectional, longitudinal study

Antibodies to ribonucleoproteins (RNP) and to the Sm antigen in sera from patients with mixed connective tissue disease (MCTD) and systemic lupus erythematosus were studied using the techniques of immunoblotting and immunoprecipitation of U small nuclear RNPs. A cross-sectional study indicated that antibodies reacting with a 68K protein were associated with anti-RNP specificity in MCTD, but rarely occurred in systemic lupus erythematosus patients' sera. A longitudinal study demonstrated the persistence of MCTD blotting patterns over many years, and the subsequent disappearance of those specificities in sera from patients who were in prolonged remission.

Pharmacokinetics of the progesterone antagonist 17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)-17 alpha-(1-propynyl) estra-4,9-dien-3-one in the rabbit

Pharmacokinetic characteristics of compound RU 486 (17 beta-hydroxy-11 beta-(4-dimethylaminophenyl)-17 alpha-(1-propynyl)estra-4,9-dien-3-one) were investigated in 6 immature estrogenized female rabbits. A dose of 3.4 mg/kg was administered either intravenously or orally, in both cases together with 3H-RU 486 (13.4 muCi/kg). The concentration of RU 486 was measured in blood plasma following isolation by thin-layer chromatography. The concentration of ether-extractable metabolites was obtained from the difference between the total ether-extractable radioactivity and the radioactivity of the isolated RU 486. Following the i.v. administration it was found that the disposition of RU 486 could be described by a biexponential curve. The half-life of the slow disposition phase of RU 486 was significantly lower (t1/2 = 52 min: P greater than 0.05) than those of RU 486 metabolites (t1/2 = 99 min). High apparent volumes of distribution of RU 486 and RU 486 metabolites (5.8 and 6.0 l/kg, respectively) indicated a high extravascular binding. Following the oral administration in oil solution, RU 486 could not be found in plasma in reliably detectable amounts due to a poor absorption and a probable first-pass effect. In the measurements of the "total RU 486" (sum of RU 486 and ether-extractable metabolites), a similar rate of terminal disposition was found for both routes of administration.