The value of hysteroscopy in the diagnosis of infertility and habitual abortion

Ninety cases of infertility and habitual abortion were analyzed by hysteroscopy between April 1983 and July 1990 in PUMC hospital. Abnormal changes of the uterine cavity were seen in 74.4%. The result of hysterosalpingography corresponded with that of hysteroscopy in 62.5%, and the result of B-ultrasound corresponded to that of hysteroscopy in 52.5%. The diagnosis of adhesion and polyps of the uterine cavity was made accurately by hysteroscopy, and both could be operated under hysteroscopy. After operative removal of the adhesion, an IUD should be put into the uterine cavity for 3 months. In 60 cases operations were performed during or after hysteroscopy. Of the 45 patients followed, 19 achieved pregnancy. Five patients achieved pregnancy after operative removal of the adhesion. It is concluded that hysteroscopy is more important than B-ultrasound and hysterosalpingography in the examination and treatment of infertility.

Synergistic effects of murine stem cell factor in combination with a variety of cytokines on the expansion of murine hematopoietic progenitor cells in short-term suspension cultures

In the present study, it is represented that the ability of murine stem cell factor (SCF) to expand hematopoietic progenitor cells in short-term suspension culture when used alone or with IL-1 beta, IL-3, IL-6, M-CSF and IL1 beta Plus IL-3. SCF alone had a limited effect on the expansion of early primitive hematopoietic progenitor cells (CFU-HPP: high proliferative potential colony forming unit, and CFU-S: colony forming unit in spleen) even at a high concentration, but expanded mature hematopoietic progenitor cells (CFU-GM: colony forming unit-granulocyte/macrophage, and BFU-E: burst forming unit-erythroid) markedly at low concentrations. When SCF was used in combination with other cytokines, the expansion of primitive hematopoietic progenitor cells was significantly increased; namely, CFU-HPP were expanded approximately 2 to 5-fold compared with SCF alone. A marked expansion of hematopoietic progenitor cells was observed in a combination of SCF plus IL-1 beta plus IL-3. In this setting, CFU-S was increased 2.2-fold compared with the number of CFU-S in fresh bone marrow and CFU-HPP were increased 8.5-fold compared with the number of primary CFU-HPP. These results suggest that these factors may be utilized in experiments of murine bone marrow transplantation (BMT) and also in human BMT. Namely, the adequate number of hematopoiesic progenitor cells and stem cells required for the successful engraftment can be obtained from small volume of peripheral or bone marrow blood by this procedure, thus obtiating the donor's burden.

Ras proteins in developmental pattern formation in Caenorhabditis elegans and Drosophila

Recent studies of genetically isolated mutants in Caenorhabditis elegans and Drosophila have revealed ras functions in developmental pattern formation. The ras proteins act as genetic switches to determine cell fates between two alternative choices during C elegans vulval development (vulval versus hypodermal cells) and during Drosophila eye development (R7 versus cone cell). In both cases, ras proteins act downstream of a receptor tyrosine kinase in a signal transduction pathway that mediates cell-cell interactions. These genetic systems may allow the further elucidation of ras-mediated developmental regulatory pathways.

[Hepatectomy under continuous normothermic interruption of hepatic blood flow in noncirrhotic patients]

Continuous normothermic interruption of hepatic blood flow for 20 minutes or longer was applied in 37 non-cirrhotic patients, including 7 having emergency operation and 30 elective operation. Hepatic blood inflow was interrupted for 40 to 47 minutes in 4 patients, 30 to 39 minutes in 7, 25 to 29 minutes in 14, and 20 to 24 minutes in 12. Postoperatively, 1 patient died of recurrent hemobilia, which was not related to intraoperative vascular interruption. Two patients had mild jaundice for 1 week after right trilobectomy, while the remaining 34 patients recovered uneventfully with no clinical hepatic insufficiency. This method is considered simple, safe, and acceptable for hepatic resection in non-cirrhotic patients.

Analysis of dominant-negative mutations of the Caenorhabditis elegans let-60 ras gene

The let-60 gene of Caenorhabditis elegans controls the choice between vulval and hypodermal differentiation in response to an inductive signal from the gonad. let-60 encodes a ras protein that acts downstream of the let-23 receptor tyrosine kinase in a signal transduction pathway. Dominant-negative mutations of let-60 [let-60(dn)] cause a reduction of the gene activity in let-60(dn)/+ heterozygotes and a vulva-less mutant phenotype. We have found that nine let-60(dn) mutations cause replacements of conserved residues. Four are in two novel positions; others are in positions known previously to cause dominant-negative mutations in mammalian cells. The locations of these lesions suggest that they disrupt the ability of the ras protein to bind guanine nucleotides. Four let-60(dn) mutant genes were introduced into wild-type animals in the form of extrachromosomal arrays and were found to generate three dominant phenotypes--lethality, vulva-less, or multivulva--depending on gene dose and alleles. The dominant lethality caused by high-dose transgenic let-60(dn) genes suggests a toxic effect of these mutant genes in early development. The dominant-negative effects of these mutations in heterozygotes are likely to be caused by competition between let-60(dn) and let-60(+) protein for a positive regulator. All let-60(dn) mutations interfere with let-60(+) activity, but some alleles have partial constitutive activity, suggesting that the ability to interact with the activator is separable from the ability to exert a physiological effect (stimulation of vulval differentiation). These dn mutations might be useful for interfering with ras-mediated signal transduction pathways in other multicellular organisms.

Short intussusception valves prevent reflux after jejunal interposition bilioduodenal anastomosis

Short whole circumference and semi-circumference intussusception valves were created in interposition cholecysto-jejunal-duodenal conduits in pigs to determine which method best prevented gastrointestinal reflux into the biliary tract. Following intravenous injection of 99 mTc-HIDA the time interval for its excretion from the liver and appearance in the duodenum was not different in either whole or semi-circumference valve animals or in controls without valves. After intragastric administration of 99 mTc-DTPA the relative radioactivity of gallbladder contents (reflux) in the cohort without valves was significantly higher than in both cohorts with valves. Animals with semi-circumferential valves in turn had significantly higher levels of nuclide than those with whole circumference valves. Reflux was observed grossly in 100% of animals without valves, in 20% of those with semi-circumference valves, and in no animals with whole circumference valves. This study indicates that both whole and semi-circumference intussusception valves placed in jejunal biliary conduits allow unimpeded flow of bile into the gastrointestinal tract. Whole circumference valves are more effective for prevention of reflux than semi-circumferential valves.

The influence of electrocortical biofeedback on performance in pre-elite archers

The purpose of the present research was to determine whether EEG biofeedback training could improve archery performance as well as self-reported measures of concentration and self-confidence. Experienced pre-elite male (N = 16) and female (N = 8) archers were randomly assigned to one of three treatment conditions: (a) correct feedback (i.e., greater left hemisphere low frequency activity), (b) incorrect feedback (i.e., greater right hemisphere low frequency activity), and (c) no feedback control. The pretest and posttest consisted of 27 shots, with EEG data collected for the left and right temporal hemispheres (T3, T4). Feedback subjects were then given EEG biofeedback, while control subjects rested for 30 min. Analyses indicated that only the performance measure was significant. The correct feedback group significantly improved performance, while the incorrect feedback group showed a significant performance decrement from pre- to posttest (Ps less than 0.05). The control group showed no significant pre-post differences in performance. EEG analyses showed differences that were consistent with the training given to the incorrect, but not the correct, feedback group. Overall, the results provide some support for the use of known relationships between EEG and performance as an effective means of providing biofeedback to affect the performance of pre-elite archers.

The let-60 locus controls the switch between vulval and nonvulval cell fates in Caenorhabditis elegans

During induction of the Caenorhabditis elegans hermaphrodite vulva by the anchor cell of the gonad, six multipotent vulval precursor cells (VPCs) have two distinct fates: three VPCs generate the vulva and the other three VPCs generate nonspecialized hypodermis. Genes that control the fates of the VPCs in response to the anchor cell signal are defined by mutations that cause all six VPCs to generate vulval tissue (Multivulva or Muv) or that cause all six VPCs to generate hypodermis (Vulvaless or Vul). Seven dominant Vul mutations were isolated as dominant suppressors of a lin-15 Muv mutation. These mutations are dominant alleles of the gene let-60, previously identified only by recessive lethal mutations. Our genetic studies of these dominant Vul recessive lethal mutations, recessive lethal mutations, intragenic revertants of the dominant Vul mutations, and the closely mapping semi-dominant multivulva lin-34 mutations suggest that: (1) loss-of-function mutations of let-60 are recessive lethal at a larval stage, but they also cause a Vul phenotype if the lethality is rescued maternally by a lin-34 gain-of-function mutation. (2) The dominant Vul alleles of let-60 are dominant negative mutations whose gene products compete with wild-type activity. (3) lin-34 semidominant Muv alleles are either gain-of-function mutations of let-60 or gain-of-function mutations of an intimately related gene that elevates let-60 activity. We propose that let-60 activity controls VPC fates. In a wild-type animal, reception by a VPC of inductive signal activates let-60, and it generates into a vulval cell type; in absence of inductive signal, let-60 activity is low and the VPC generates hypodermal cells. Our genetic interaction studies suggest that let-60 acts downstream of let-23 and lin-15 and upstream of lin-1 and lin-12 in the genetic pathway specifying the switch between vulval and nonvulval cell types.

let-60, a gene that specifies cell fates during C. elegans vulval induction, encodes a ras protein

Genetic analysis previously suggested that the let-60 gene controls the switch between vulval and hypodermal cell fates during C. elegans vulval induction. We have cloned the let-60 gene, and shown that it encodes a gene product identical in 84% of its first 164 amino acids to ras gene products from other vertebrate and invertebrate species. This conservation suggests that the let-60 product contains all the biochemical functions of ras proteins. Extrachromosomal arrays of let-60 ras DNA cause cell-type misspecification (extra vulval fates) phenotypically opposite to that caused by let-60 ras loss-of-function mutations (no vulval fates), and suppress the vulvaless phenotype of mutations in two other genes necessary for vulval induction. Thus, the level and pattern of let-60 ras expression may be under strict regulation; increase in let-60 ras activity bypasses or reduces the need for upstream genes in the vulval induction pathway.

Nucleosome loss activates yeast downstream promoters in vivo

Nucleosome depletion can be made to occur in yeast by addition of glucose to strains containing the histone H4 gene under GAL promoter control. This leads to the activation of downstream promoter elements (TATA box and initiation, I, region) of three different regulated yeast promoters fused to the E. coli lacZ gene. Nucleosome loss activates the PHO5 downstream element in the presence or absence of the upstream activator sequences (UAS) through which PHO5 induction is normally mediated. The cytochrome C (CYC1) and galactokinase (GAL1) promoters are normally repressed by glucose through their UAS elements. However, when these UAS are deleted, the remaining downstream promoters are also activated by glucose-mediated nucleosome loss. These data suggest that nucleosome loss increases transcription initiation and subsequent elongation in vivo. They also indicate that the proteins which recognize the downstream promoter are activated and functional, at least in part, even in the absence of the UAS complex.

Extremely conserved histone H4 N terminus is dispensable for growth but essential for repressing the silent mating loci in yeast

Yeast histone H4 function was probed in vivo by deleting segments of this extremely conserved 102 amino acid protein. Deletions in the hydrophobic core of H4 are lethal and block chromosomal segregation. In contrast, deletions at the hydrophilic N terminus (residues 4-28) and C terminus (residues 100-102) are viable. However, N-terminal deletion alters normal chromatin structure and lengthens the cell cycle, especially G2. Surprisingly, removal of the H4 N terminus also derepresses the silent mating type loci, HML alpha and HMRa, disrupting mating. This activation is specific since other regulated genes (GAL10, PHO5, CUP1) are repressed and induced normally in these cells. Deletions of the hydrophilic N termini of H2A or H2B do not show this effect on mating. These experiments allow us to define a unique H4 function that is not shared by other histones (H2A and H2B).

D-lysergic acid activation and cell-free synthesis of D-lysergyl peptides in enzyme fractions from the ergot fungus Claviceps purpurea

The D-lysergic acid activating enzyme from the ergot fungus Claviceps purpurea was purified to near homogeneity. It has a native Mr of about 245,000 and in its denatured form is a single polypeptide chain of Mr 62,000. The enzyme catalyzes the ATP-pyrophosphate exchange reaction dependent on D-lysergic acid and, though much less, that dependent on dihydrolysergic acid. Western blot analysis of SDS electropherograms of crude protein extracts from C. purpurea using monospecific antibodies directed against the D-lysergic acid activating enzyme revealed the immunostaining of one particular band which was identical with that of the D-lysergic acid activating enzyme. No significant immunoreactive band with higher molecular weight was seen, which precludes the possibility that the enzyme had arisen from the proteolysis of a high molecular weight ergot peptide synthetase. An ammonium sulfate fractionated enzyme fraction was prepared from C. purpurea strain C1 that catalyzed the incorporation of D-lysergic acid into two peptides which besides D-lysergic acid contained alanine, phenylalanine, and proline. Dihydrolysergic acid was efficiently incorporated into the corresponding dihydrolysergic acid containing analogues of the two compounds. Radiochemical analysis and degradation studies suggest that the two D-lysergic acid containing peptides most probably are N-[N-(D-lysergyl)-L-alanlyl]-L-phenylalanyl-L-proline lactam and N-[N-(D-lysergyl)-L-analyl]-L-phenylalanyl-D-proline lactam, respectively. N-[N-(D-Lysergyl)-L-alanyl]-L-phenylalanyl-L-proline lactam is considered to be the immediate precursor of ergotamine.(ABSTRACT TRUNCATED AT 250 WORDS)

Depletion of histone H4 and nucleosomes activates the PHO5 gene in Saccharomyces cerevisiae

We have previously constructed a yeast strain (UKY403) whose sole histone H4 gene is under control of the GAL1 promoter. This yeast arrests in G2 upon glucose treatment as a result of histone H4 depletion. The yeast PHO5 gene contains phase nucleosomes covering promoter (UAS) sequences in the PHO5 repressed state and it has been suggested that nucleosomes prevent the binding of positively acting factors to these UAS sequences. Using UKY403 we examined the length of polynucleosomes and nucleosome phasing in the PHO5 upstream region by the use of micrococcal nuclease and indirect end-labeling. It was found that glucose arrest led to a severe disruption in PHO5 chromatin structure and that most nucleosomes had their position altered or were lost from the PHO5 promoter region. Cell undergoing nucleosome depletion synthesized large quantities of accurate PHO5 transcripts even under repressive, high inorganic phosphate conditions. Histone H4 depletion did not appear to affect the repression or activation of another inducible yeast gene, CUP1. Arrest with landmarks in early G1 (in the cell division cycle mutant cdc28) or in various stages of G2 (in cdc15, cdc17 and cdc20) does not activate PHO5; nor does arrest due to chromosome topology changes (in top2 or the top1top2 topoisomerase mutants). cdc14, which has its arrest landmark at a similar point in the cell cycle as cdc15, does derepress PHO5. However, since it also leads to derepression of CUP1 it is probably functioning through an independent mechanism. Therefore, our data suggest that nucleosomes regulate PHO5 transcription.

Effects of histone H4 depletion on the cell cycle and transcription of Saccharomyces cerevisiae

We have constructed a yeast strain (UKY403) in which the sole histone H4 gene is under control of the GAL1 promoter. This allows the activation of H4 mRNA synthesis on galactose and its repression on glucose. UKY403 cells, pre-synchronized in G1 with alpha-mating factor, have been used to show that glucose treatment results in the loss of approximately half the chromosomal nucleosomes. This depletion is only partially reversible when the H4 gene is reactivated on galactose. It was found that the resultant lethality manifests itself first in S phase, the period of nucleosome assembly, but leads to highly synchronous arrest in G2 and a virtually complete block in chromosomal segregation. Histone H4-depleted chromatin was analyzed for its efficiency as a template for all three RNA polymerases. Using pulse-labeling, we find no evidence for altered transcription by RNA polymerase I (25S, 18S and 5.8S rRNAs) or RNA polymerase III (5S rRNA, tRNAs). Northern blot analysis was used to measure levels of RNA polymerase II transcripts. There was little effect on the activation or repression of the CUP1 chelatin gene. While there may be some decrease in the level of certain mRNAs (e.g. HIS4, ARG4) other message levels (HIS3, TRP1) show little change upon glucose repression. Therefore, nucleosome loss certainly does not have a general effect on transcription.

Histone H2B repression causes cell-cycle-specific arrest in yeast: effects on chromosomal segregation, replication, and transcription

To determine which cellular processes are dependent on histones, we blocked histone H2B mRNA synthesis in asynchronously growing yeast after fusing the H2B gene to a repressible GAL10 promoter. Chromosomal segregation, replication, and transcription were then examined. We found that the cells arrested in mitosis, with a cell division cycle (cdc) phenotype. Chromatin structure and nuclear segregation were disrupted. A full round of DNA replication took place after the repression of histone H2B mRNA synthesis. Active transcription and the induction of new transcripts also continued in the arrested cells.

Yeast histone H2A and H2B amino termini have interchangeable functions

The N-terminal ends of histones H2B and H2A have very different sequences and rates of evolution. However, they both extend from the nucleosome core and are positively charged. Short sequences at the C termini of both proteins also differ from each other and appear to be hydrophilic. Deletions at the N and C termini of yeast histones H2B2 and H2A1 do not obviously affect the cell's viability under normal growth conditions. However, deletions at the N termini of both H2B and H2A in the same cell are lethal or result in greatly reduced viability. Even switching portions of the N termini between H2B and H2A to create two chimeric histone proteins within the same cell has no obvious effect on viability. This supports the argument that the N-terminal end of one protein complements the function of the other.

Adenovirus stimulation of transcription by RNA polymerase III: evidence for an E1A-dependent increase in transcription factor IIIC concentration

Human cells expressing adenovirus E1A proteins transcribe transfected tRNA and adenovirus VAI genes at greater than 10-fold higher levels than uninfected HeLa cells. Here we show that the increased transcription observed in vivo is reflected in the in vitro transcriptional activity of cell extracts. Depletion of E1A protein from these extracts by immunoprecipitation with a monoclonal antibody did not diminish the activity, suggesting that E1A proteins do not stimulate transcription directly. Fractionation of the extracts by chromatography on phosphocellulose suggests that the higher activity of extracts of adenovirus-infected cells was due to increased activity of the transcription factor (TF) which is the limiting component required for specific initiation of tRNA and VAI transcription in extracts of uninfected HeLa cells, i.e. TFIIIC. Template commitment titrations further suggest that the increased TFIIIC activity was due to an increase in the concentration of active TFIIIC. On the basis of these results and recent genetic analyses of early adenovirus promoters, we suggest that E1A proteins stimulate transcription of adenovirus genes indirectly by increasing the effective in vivo concentration of the limiting cellular transcription factors required for their transcription.

Crossed aphasia in a right-handed bilingual Chinese man: a second case

A persistent nonfluent aphasia following a right cerebral infarction developed in a 74-year-old right-handed Chinese man. Computerized axial tomography localized the lesion in the right frontal lobe. This case is similar to a previously reported one, also with crossed aphasia in a bilingual and dextral Chinese person. Despite these two independent observations and in spite of the fact that unusual cerebral organization might be related to early learning of a nonalphabetic (ideographic) language, preliminary sampling has failed to demonstrate a greater incidence of crossed aphasia in two separate Chinese populations.