PubMed Health⌕ Search

Biomedical subjects

M Neuberg

Publications and source records attributed to M Neuberg.

At least 19 recordsLinked to original sources
PubMed2001

[Reproductive behavior after the flood disaster in Klodzko region--July 1997].

RATIONALE: Flood disasters destroy environment of many people by causing physical as well as psychological harm. This may affect procreational behavior of the victims. DESIGN: This study examines reproductive behavior (number of live births) among the survivors from the flood disaster in Klodzko Region which took place in July 1997. The observation period was three years (1998-2000). MATERIALS AND METHODS: The harmed population consisted of 3986 subjects. The population from Klodzko Region which was exposed to flood disaster in 1997 consisted of 107,032 people. Among the injured population there were 1037 women in reproductive age. This population was studied. RESULTS: The results show significantly higher number of live births per 1000 and birth-rate in studied women as compared to the total population of a district. Psychological background of an observed phenomenon was discussed.

Adaptation, Psychological↗
PubMed2000

[The use of forceps delivery in own analysis].

OBJECTIVES: The clinical analysis of deliveries ended by forceps over the period of ten years. DESIGN: Review of perinatal outcome and indications to use outlet and low forceps or midforceps. MATERIALS AND METHODS: Author analysed 137 forceps deliveries in comparison to control group of 250 normal, vaginal labours. Obstetrical history, indications to use vaginal operation, duration of labour, hospitalisation time, newborns state in Apgar score or arterial cord pH, PaO2, and fetal or maternal injures were statistically analysed. The American College of Obstetricians and Gynecologists (ACOG) 1988 forceps classification be adopted for deliveries. Using outlet, low forceps and midforceps concerned with vaginal operation. RESULTS: The common indications to use outlet or low forceps were prolonged second stage of labour. The most frequent indication for the midforceps was a risk of fetal asphyxia and neonatal hypoxia. A major fetal injury occurred in midforceps, particularly with fetal head rotations. Furthermore, midforceps delivery increased incidence of maternal perineal trauma. The outlet or low forceps was safe for fetal outcome and trauma of the birth canal in comparison to normal vaginal delivery. CONCLUSIONS: The prophylactic use of outlet or low forceps has beneficial impact on the neonate because it shortens second stage of labour and decreased the incidence of neonatal hypoxia. The midforceps delivery increased a perinatal disorders and using cesarean section are better for child and mother.

Asphyxia Neonatorum↗
PubMed1999

[Repeated amenorrhea in an adolescent girl in the course of flood disaster in Kłodzko Region, July 1997].

OBJECTIVES: A natural disaster has been defined as a disruption of human ecology that exceeds the capacity of the community to function normally. DESIGN: After the flood disaster in Kłodzko Region, July 1997, the major problem in female adolescents was observed: secondary amenorrhea. MATERIALS AND METHODS: 17 female adolescents, aged 13-18, which injured from the flood disaster with secondary amenorrhea were investigated. A control random group consists of 17 girls diagnosed before oral contraception. Diagnostic work-up includes history, physical and psychological examinations, hormonal profiles, transvaginal ultrasonography, color Doppler analysis of utero-ovarian arterial blood flow. RESULTS: FSH, LH, E2 plasma levels and LH/FSH ratio were significantly lower in the amenorrheic group compared to normal girls. Prolactin serum levels after metoclopramid administration were significantly higher in the amenorrheic group. Lower impedance to blood flow in the intraovarian arteries have been shown. Psychosomatic disorders related to hypothalamic amenorrhoea were diagnosed. CONCLUSIONS: Psychosocial stress observed during the flood disaster caused hypogonadotropic hypogonadism amenorrhoea in the female adolescents.

Adolescent↗
PubMed1998

[The analysis of the course of pregnancy, delivery and postpartum among women touched by flood disaster in Kotlin Kłodzki in July 1997].

OBJECTIVES: A natural disaster has been defined as a disruption of human ecology that exceeds the capacity of the community to function normally. Little is known about the influence of flood disaster on reproductive outcomes. DESIGN: This study reviews perinatal medical problems in pregnant women during the flood disaster from Kłodzko Region in July 1997. MATERIALS AND METHODS: 47 pregnant women were investigated which injured from the flood disaster. We observed a psychosocial stress in this women. A control random group consists of 100 pregnant women in 1996. RESULTS: Reproductive outcomes include pregnancy loss in 55.3% and other severe disorders: premature delivery, missed abortion, birth asphyxia, premature rupture of membranes, intrauterine growth retardation. CONCLUSIONS: Psychosocial stress observed during the flood disaster cause many perinatal complications and pregnancy loss. Intensive perinatal medical care must usually be provided from outside the disaster area.

Adolescent↗
PubMed1998

[Own experience with internal iliac and ovarian artery ligation in gynecological and oncological surgeries].

Internal illiac and ovarian artery ligation was performed in 7 patients as a life saving measure (group I) and in 12 patients as a prophylactic procedure (group II) in 116 pelvic operations for gynaecological malignancy. The author presents own surgical technique for internal iliac and ovarian arteries ligation. The purpose of analysis was to identify a surgical complications after the ligation in the study groups. Surgical complications in the group of prophylactic ligation were statistically significant low. It is advisable to adopt this procedure as a routine in all difficult pelvic operations, particularly radical operations for gynaecological malignancy.

Adult↗
PubMed1997

The p53/IGF-1 receptor axis in the regulation of programmed cell death.

The loss or functional inactivation of tumor suppressor genes appears to be one of the most fundamental genetic mechanisms of tumorigenesis, and rational insights into the signaling pathways of tumor suppressor genes have emerged as a successful strategy of identifying novel drug discovery targets downstream of the tumor suppressor protein itself. Elucidation of novel pathways downstream of p53 have established a link between this important tumor suppressor gene and the insulin-like growth factor-1 receptor (IGF-1r), either via direct regulation of IGF-1 receptor levels, or modulation of IGFs via transactivation of the insulin-like growth factor-binding protein 3 (IGF-BP3) gene. Binding of IGF-BP3 to IGFs inhibits both their mitogenic and cell survival functions, highlighting a novel pathway whereby p53 may regulate apoptosis in tumor cells.

Animals↗
PubMed1993

A role for the transcription factors Mbp1 and Swi4 in progression from G1 to S phase.

In budding yeast genes that encode G1 cyclins and proteins involved in DNA synthesis are transcriptionally activated in late G1. A transcription factor, called SBF, is composed of Swi4 and Swi6 proteins and activates transcription of G1 cyclin genes. A different, but related, complex called MBF binds to MCB elements (Mlu I cell cycle box) found in the promoter of most DNA synthesis genes. MBF contains Swi6 and a 120-kilodalton protein (p120). MBF was purified and the gene encoding p120 (termed MBP1) was cloned. A deletion of MBP1 was not lethal but led to deregulated expression of DNA synthesis genes, indicating a direct regulatory role for MBF in MCB-driven transcription. Mbp1 is related to Swi4. Strains deleted for both MBP1 and SWI4 were inviable, demonstrating that transcriptional activation by MBF and SBF has an important role in the transition from G1 to S phase.

Amino Acid Sequence↗
PubMed1992

[Decidual prolactin].

Human prolactin (hPRL) is a hormone produced by the lactotropic cells of the hypophysis and by the endometrium converted to decidua in pregnancy. Prolactin of decidual origin is identical with the pituitary hormone. Decidual prolactin is released mainly by the extraplacental fetal membranes. Prolactin production was found also in the endometrium in late secretory phase of normal menstrual cycle. It was noted that hPRL production by the decidua in various periods of pregnancy is closely correlated with hPRL concentration in the amniotic fluid. Peak hPRL release into the amniotic fluid is in the 24th week of pregnancy. The most important biological function of decidual prolactin is its effect on water and electrolyte transport for the needs of the fetus, and this transport takes place mainly across the fetal membranes. Moreover, it was found that prolactin affects the synthesis of fetal surfactant, influences calcium absorption in the fetal intestine. Calcium and phosphorus are obtained by the fetus from the amniotic fluid. Many authors suggest that decidual prolactin has a role in the process of implantation and early development of the blastocyst.

Amniotic Fluid↗
PubMed1991

Multiple regions of v-Fos protein involved in the activation of AP1-dependent transcription: is trans-activation crucial for transformation?

We show that trans-activation by v-Fos requires several functionally separable regions, including the leucine repeat, the basic DNA-binding region, a directly adjacent acidic cluster, and additional flanking sequences. Structural alterations in the flanking regions are in part responsible for the greater trans-activating potential of the fos gene product of the Finkel-Biskis-Reilly mouse osteosarcoma virus, FBR-MuSV. A point mutation in the acidic cluster, which is known to activate the immortalizing potential of Fos, leads to a significant increase in trans-activation. However, comparison of the trans-activating and transforming properties of mutant Fos proteins suggests that functions other than trans-activation are involved in the induction of transformation.

Cell Transformation, Neoplastic↗
PubMed1991

Mutagenesis of the DNA contact site in Fos protein: compatibility with the scissors grip model and requirement for transformation.

To elucidate the mechanisms involved in the transformation by fos we have initiated a study pertaining to the identification of molecular functions of Fos protein that are crucial for transformation. We have previously reported that the presence of an intact leucine zipper in Fos is an absolute requirement for the induction of transformation, but that the autorepression function of Fos is dispensable. We now show that Fos protein also needs an intact DNA (TRE)-binding site to be able to transform. Amino acid substitutions in this domain of Fos which impair DNA binding also destroy the transforming potential of Fos, suggesting that the interaction of Fos-Jun complexes with TREs may be a crucial part of Fos-induced transformation. This hypothesis is further strengthened by our observation that Fos and Jun can cooperate in the induction of transformation. We show that a Fos protein which contains a Jun leucine zipper and is thus capable of dimerization is still dependent on the presence of exogenous Jun to induce transformation. The critical positions in the Fos DNA-binding site include those which the 'scissors grip' model predicts to be crucial, although the DNA-binding site in Fos seems to extend beyond the basic region into an adjacent cluster of acidic amino acids.

Amino Acid Sequence↗
PubMed1990

Products of the fos and jun proto-oncogenes bind cooperatively to the AP1 DNA recognition sequence.

The products of the proto-oncogenes c-fos and c-jun form a tight protein complex that is a major component of the transcription factor AP1. To analyze the role of fos in the binding of this complex to the AP1 DNA recognition sequence and the mechanism of interaction in further detail, we have expressed a fos protein in E. coli using an expression vector containing the temperature-inducible lambda PL promoter and a synthetic translational start codon. The fos protein encoded by this construct (termed Baf) was enriched by biochemical purification techniques and was found to form a specific complex with c-jun obtained by in vitro transcription/translation. As shown in gel retardation assays, the baf/jun complex binds to the AP1 DNA recognition sequence with high affinity, while no significant binding was observed with either of the individual protein components, indicating cooperative DNA binding of the two proteins. The fact that the bacterial baf protein does not undergo glycosylation indicates that the post-translational modification of eukaryotic c-fos with N-acetylglucosamine is not required for the formation of a stable fos/jun/DNA complex.

Binding Sites↗
PubMed1989

trans-repression of the mouse c-fos promoter: a novel mechanism of Fos-mediated trans-regulation.

Fos protein can trans-activate AP-1-dependent gene expression and trans-repress the c-fos promoter. Although we find that trans-repression is enhanced by coexpression of c-Jun, it does not require any of the AP-1 or ATF sites in the mouse c-fos promoter. A major target for repression is the serum response element (SRE). Fos mutants with an impaired leucine zipper are defective in trans-repression and transformation, suggesting that these functions involve the formation of Fos protein complexes. In contrast, mutations that abolish DNA binding of Fos enhance trans-repression but destroy the transforming potential of Fos. In addition, v-Fos protein efficiently transforms but is unable to trans-repress. These findings point to different mechanisms involved in trans-activation and trans-repression and suggest that trans-repression of the type described here is neither sufficient nor required for Fos-induced transformation.

Animals↗
PubMed1989

Asymmetrical recognition of the palindromic AP1 binding site (TRE) by Fos protein complexes.

Fos and Jun proteins form a tight complex which binds specifically to the AP1 recognition sequence, a palindromic DNA element also referred to as the TPA responsive element (TRE). To elucidate the mechanism of Fos-Jun interaction with the TRE we have performed UV cross-linking studies using oligonucleotides where thymines were replaced with bromouracil. Our results indicate that both Fos and Jun directly contact the TRE but that the interaction of Fos and Jun with thymines in structurally equivalent positions in the two half sites of the TRE is different. In addition, we have carried out a comprehensive mutagenesis study of the TRE by introducing all possible point mutations plus thymine----uracil substitutions into the palindromic TRE core sequences and the adjacent nucleotides on both sides. The results of this analysis clearly show that the palindromic TRE is asymmetrical with respect to binding of Fos-Jun. We also show that a Fos protein complex with a homodimeric DNA binding site binds considerably less efficiently to TRE mutants with a perfect dyad symmetry compared with the binding to the wild-type TRE. This demonstrates that the asymmetrical recognition of the TRE is not due to the heterodimeric nature of the Fos/Jun complex but directly related to an asymmetry in the TRE sequence. The methyl groups of all four thymine residues within the TRE seem to be functionally crucial since thymine----uracil substitutions strongly reduce or abolish binding to Fos/Jun. The relevance of structurally equivalent methyl groups in the TRE core sequence is different, lending further support to the conclusion that the TRE is asymmetrical.

Animals↗
PubMed1989

A Fos protein containing the Jun leucine zipper forms a homodimer which binds to the AP1 binding site.

The TPA (12-O-tetradecanoyl-phorbol-13-acetate) responsive element (TRE) is recognized by the inducible transcription factor AP1, a heterodimeric complex of Fos- and Jun-protein subunits, which each contain a specific structure known as the leucine zipper through which they interact. Studies using site-directed mutagenesis have shown that a basic region adjacent to the leucine zipper in Fos is crucial for the interaction of the Fos-Jun complex with the TRE, and probably represents a site of interaction with DNA. The functionally crucial amino acids in this region are almost completely conserved between Fos and Jun (refs 6, 7 and 11; M.N. and R.M., unpublished results), indicating the formation of a nearly symmetrical DNA-binding site in the Fos-Jun complex. Whereas Jun can form a homodimeric protein complex which binds to the TRE, Fos is unable to do so. The Fos-Jun heterodimer, however, possesses at least a 30-fold-higher affinity for the TRE than does the Jun-Jun homodimer, indicating cooperative binding. Because Fos cannot form a homodimer it is not known whether Fos specifically recognizes part of the TRE or has a different role in the binding of the Fos-Jun complex to DNA. Here we report that exchanging the leucine zipper in Fos with that of Jun generates a protein (termed psi-Fos) that can form a complex with Fos. This Fos-psi-Fos complex, and to a lesser extent a homodimeric psi-Fos complex, exhibits specific binding to the TRE. This finding strongly supports the hypothesis that Fos and Jun form a nearly symmetrical DNA-binding site that interacts with the palindromic TRE.

Binding Sites↗
PubMed1989

Two functionally different regions in Fos are required for the sequence-specific DNA interaction of the Fos/Jun protein complex.

THE products of the cellular and retroviral fos genes associate with other nuclear proteins, among them the transcription factor AP1/Jun (see ref. 3 for a review). The Fos/Jun complex binds to a specific symmetrical DNA recognition sequence (termed TRE), thus stimulating transcription of the respective gene. Here, we show that two distinct regions in Fos are required for the formation of a Fos/Jun/TRE complex. These are the leucine zipper, involved in the association with Jun, and a directly adjacent basic region. Specific amino-acid substitutions in this basic, presumably alpha-helical, region abolish the interaction of Fos/Jun with the TRE but not the association of the two proteins. The functionally crucial amino acids are located in a region of Fos which is structurally similar to the putative DNA-binding sites in Jun and in the yeast transcriptional activator GCN4 (refs 15 and 16).

Amino Acid Sequence↗
PubMed1989

The leucine repeat motif in Fos protein mediates complex formation with Jun/AP-1 and is required for transformation.

Cellular and viral Fos proteins form a tight complex with other nuclear proteins, including the transcription factor and proto-oncogene AP-1/Jun. We have mapped the c-Jun binding site in Fos to a region containing regularly spaced leucine residues recently suggested to interdigitate with a similar structure in Jun. Substitution of single or multiple leucine residues or the alteration of leucine phasing by insertion of additional amino acids reduces or abolishes the binding to Jun, while the substitution of other amino acids has no noticeable effect. These results strongly suggest that the formation of a "leucine zipper" mediates the interaction between Fos and Jun. We also show that the differential binding of the various Fos mutants correlates with their potential to trans-activate AP-1-dependent transcription and to induce morphological transformation.

Animals↗
PubMed1987

Involvement of common and cell type-specific pathways in c-fos gene control: stable induction of cAMP in macrophages.

The c-fos proto-oncogene is rapidly and transiently induced by PDGF in fibroblast and by CSF-1 in macrophages. In both cells, the breakdown of phospholipids with the ensuing activation of protein kinase C (PKC) and intracellular release of Ca2+ seems to play a role in the induction of c-fos. The transient induction of c-fos mRNA and protein by PDGF is both increased and prolonged by inhibitors of calmodulin, apparently by inhibiting the degradation of c-fos mRNA. While no response to cyclic nucleotides is observed in fibroblasts, cAMP is a strong inducer of c-fos in macrophages. In contrast to the transient induction by PKC/Ca2+, cAMP induces stable transcription of the c-fos gene for many hours, suggesting the existence of different mechanisms regulating c-fos transcription in the same cell.

Animals↗