P892 Accuracy of right atrial pressure estimation using a multi-parameter approach derived from Inferior vena cava semi-automated edge-tracking echocardiography

Background

In clinical practice, as stated in the ASE guidelines, the echocardiographic estimation of right atrial pressure (RAP) is based on the size of the inferior vena cava (IVC) and its inspiratory collapse. However, this method has proven to have limits of reliability and reproducibility. The use of a recently developed software that with a semi-automatic technique highlight the edges of the IVC could help to standardize the echocardiographic assessment of RAP.

Aim of the study: The aim of the study was to assess feasibility and accuracy of a new semi-automated approach to estimate the RAP.

Standard acquired echocardiographic images were processed with a semi-automatic technique, indexes related to the collapsibility of the vessel during inspiration (Caval Index, CI), during the whole respiratory cycle (Respiratory Caval Index, RCI) and through the heart cycle transmitted movements’ (Cardiac Caval Index (CCI) were derived (figure 1).

Using these indexes, we developed two models:

a) the Binary Tree Model (BTM), further divided in BTM3 and BTM5 (RAP estimated in 3 and 5 classes, respectively);

b) the Regression Model (RM), further divided in RM linear (continuous model) and RM3 and RM5 (RAP estimated in 3 and 5 classes respectively).

RAP assessed using these innovative techniques were compared with two standard estimation (SE) echocardiographic methods A and B.

Direct RAP measurements obtained during a right heart catheterization (RHC), performed within 6 hours, were used as reference.

Results

62 consecutive ‘all-comers’ patients that had a RHC were enrolled; 13 patients were excluded for technical reasons. Therefore 49 patients were included in this study (26 males and 23 females; mean age of 62.2 ± 15.2 years, 75.5% pulmonary hypertension, 34.7% severe left ventricular dysfunction and 51% right ventricular dysfunction). The two SE methods showed poor accuracy for RAP estimation (method A: ME = 51%, R2= 0.22; method B: ME = 69%, R2= 0.26). Instead, the new semi-automatic methods BTM3 and BTM5 based on parameters derived from IVC edge tracking (mean IVC diameter, CI, CCI and RCI) had a misclassification error of only 14% (R2 = 0.47) and 22% (R2 = 0.61), respectively, to classify RAP. The accuracy was lower for RM than BTM (RM3: ME = 61%, R2 = 0.39; RM5: ME = 55%, R2 = 0.39). However, the RM showed the lowest mean bias in estimating RAP: 0.23 [-8.34; 8.81] mmHg.

Conclusions

A multi-parametric approach using the new indexes, such as CCI and RCI, derived from a semi-automated edge tracking of the IVC is a promising tool for a more accurate estimation of RAP. This study proposes an innovative method for the non-invasive estimation of the RAP, which requires confirmation on larger population.

Abstract P892 Figure 1

Nucleoli, rRNA genes and ITS region in Posidonia oceanica (L.) Delile

The maximum number of nucleoli was counted in interphase nuclei of Posidonia oceanica, and a restriction pattern of nuclear rDNA was obtained after digestion with four restriction endonucleases and Southern hybridization. P. oceanica has only one type of ribosomal gene whose size was estimated to be 18.5 kbp long. The nucleotide sequence of the entire ITS region was also determined by direct sequencing of PCR amplified DNA fragments. The sequence of the ITS region was aligned with those of homologous regions of other monocots available in literature, and phylogenetic trees were obtained.

Characterization of the aldolase B intronic enhancer

The aldolase B gene is transcribed at a high level in the liver, kidney, and small intestine. This high level of gene expression results from cooperation between a weak but liver-specific promoter and an intronic activator. A deletional study of this activator present in the first intron allowed us to ascribe the maximal enhancer function to a 400-base pair (bp) fragment (+1916 to + 2329). This enhancer is highly liver-specific and enhances the activity of heterologous minimal promoters in a position and distance-independent fashion in transiently transfected Hep G2 hepatoma cells. The aldolase B enhancer is composed of two domains, a 200-bp module (Ba) inactive by itself but which synergizes with another 200-bp module (Bb) that alone retains 25% of the total enhancer activity. The Bb sequence is 76% homologous between human and rat genes and contains several binding sites for liver-enriched nuclear factors. By electrophoretic mobility shift assays, we demonstrated that elements 5 and 7 bind hepatic nuclear factor 1 (HNF1), whereas element 2 binds hepatic nuclear factor 4 (HNF4). A functional analysis of the enhancer whose elements have been mutated demonstrated that mutation of any of the HNF1 sites totally suppressed enhancer activity, whereas mutation of the HNF4-binding site reduced it by 80%.

Mature cystic teratoma: a clinicopathologic evaluation of 517 cases and review of the literature

OBJECTIVE

To evaluate the clinical and pathologic presentation of mature cystic teratomas and the trends in management over a 14-year study period.

METHODS

Tumor registry data and medical records between January 1, 1975 and December 31, 1989 were analyzed with respect to patient age, tumor size, bilaterality, malignant transformation, and treatment.

RESULTS

Five hundred seventy-three tumors were removed from 517 patients. The median and mean (+/- standard deviation) age was found to be 30 and 32 +/- 11.3 years, respectively. Three hundred ten (60%) of the patients were asymptomatic. The mean tumor size was 6.4 +/- 3.5 cm. The bilaterality rate was 10.8%. The rate of torsion was 3.5%; larger tumors underwent torsion more frequently than smaller tumors (P = .029). The rate of malignant transformation was 0.17%. The mean cyst diameter for patients undergoing cystectomy was 5.7 +/- 2.4 cm; for oophorectomy, 8.0 +/- 4.1 cm; and for hysterectomy, 6.1 +/- 3.8 cm. Oophorectomies were performed for larger tumors when compared to cystectomies (P = .01). The number of hysterectomies was stable throughout the study period, whereas the number of oophorectomies decreased and the number of cystectomies increased markedly. Contralateral ovarian biopsy was common (48.5%) early in the study period. By 1989, the biopsy rate was less than 1%.

CONCLUSIONS

We found the prevalence rates of symptomatic tumors, torsion, and malignant degeneration to be less than those previously reported by most other investigators. In addition, there has been an important change over the past 14 years in the management of these neoplasms, with an increased tendency for ovarian preservation, as evidenced by the more frequent use of cystectomy and a decrease in contralateral ovarian biopsy.

Stage II adenocarcinoma of the endometrium treated by two standard regimens of combined preoperative irradiation and surgery

We retrospectively analyzed 77 patients with stage II endometrial carcinoma treated with standard regimens of preoperative radiotherapy (RT) and surgery (S). The age range was 31-74 years with a median of 56.3 years. Thirty-three patients received 40 Gy whole pelvis RT followed by either radical or modified radical hysterectomy. Forty-four patients received 50 Gy whole pelvis RT and sequential intrauterine and intravaginal cesium-137 brachytherapy followed by a simple hysterectomy. Median follow-up was 111 months. No patient was lost to follow-up. The overall 5-year actuarial survival was 78%. There was no significant difference between the two treatment groups. Several prognostic variables were analyzed. Those with histologic grade I and II had 5-year survival of 89% and 83%, respectively, compared to 62% for grade III (P =0.045). The 5-year survival for microscopic cervical involvement was 87% compared to 59% for gross involvement (P= 0.008). Patients with negative or microscopic residual tumor in the surgical specimen and those with negative lymph nodes had less risk of treatment failure. Local failure occurred in only 9%. Major complications (3%) were seen only in the radical surgery group. Combined preoperative RT and S provide high cure rates with minimal complications for patients with stage II endometrial carcinoma. Patients with adverse prognostic factors are candidates for trials of more aggressive local and systemic therapy.

Activity of the rat liver-specific aldolase B promoter is restrained by HNF3

Although it contains binding sites for HNF1, NFY and C/EBP/DBP, the proximal promoter of the aldolase B gene is surprisingly weak when tested by transient transfection in differentiated hepatoma cells. This low activity could be due to overlapping between HNF1 and HNF3 binding sites in element PAB, from -127 to -103 bp with respect to the cap site. Replacement of the PAB region by a consensus HNF1 binding site unable to bind HNF3, results in a 30 fold activation of the promoter, in accordance with the hypothesis that activity of the wild-type promoter is normally restrained by HNF3 binding to PAB competitively with HNF1. Consistently, transactivation of the wild-type promoter by excess HNF1 is very high, most likely due to the displacement of HNF3, while the construct with the exclusive HNF1 binding site is weakly transactivated by HNF1. The inhibitory effect of HNF3 on HNF1-dependent transactivation is clearly due to competition between these two factors for binding to mutually exclusive, overlapping sites; indeed, when HNF1 and HNF3 sites are contiguous and not overlapping, the resulting promoter is as active as the one containing an exclusive HNF1 binding site. A construct in which PAB has been replaced by an exclusive HNF3 binding site is weakly expressed and is insensitive to HNF3 hyperexpression. DBP-dependent transactivation, finally, is independent of the nature of the element present in the PAB region.

Competition between transcription factors HNF1 and HNF3, and alternative cell-specific activation by DBP and C/EBP contribute to the regulation of the liver-specific aldolase B promoter

The aldolase B proximal promoter is controlled by at least five elements spanning from -190 to -103 bp with respect to the start site of transcription. From 5' to 3', we found: a negative DE element, an activating C/EBP-DBP binding site, a CCAAT box binding NFY that seems to play a negative role, and an activating element consisting of two overlapping binding sites for HNF-1 and HNF-3. Contransfection experiments of aldolase B/CAT constructs and of expression vectors for different transcription factors were carried out in human hepatoma Hep G2 cells. We found that DBP and HNF-1 are strong transactivators of the aldolase B promoter while C/EBP and vHNF-1 are only weak activators and HNF-3 alone does not modify such activity. Deletion of the distal negative element results in a similar transactivation by C/EBP and DBP, enhanced for the former and reduced for the latter. In hepatocytes in primary culture, the strong transactivator is C/EBP while DBP is essentially inactive. This tissue-specificity of C/EBP and DBP action could depend on interaction with tissue-specific proteins bound to a neighbouring site, probably DE. Finally, HNF3 behaves as a very strong anti-activator of the aldolase B promoter. It competitively antagonizes transactivation by HNF-1 and non-competitively transactivation by DBP. This negative effect of HNF-3 and tissue-specificity of the transactivation potential of DBP and C/EBP are unique features of the aldolase B promoter.

Interplay of an original combination of factors: C/EBP, NFY, HNF3, and HNF1 in the rat aldolase B gene promoter

The rat aldolase B 5' flanking region (nucleotides - 194 to +41) contains sufficient information for liver-specific expression. A detailed investigation of factors binding to the rat aldolase B 5' flanking region has allowed us to identify three distinct factors that filled different sites of this region (A, B, C). The liver-enriched C/EBP or related factors bind to box C, as demonstrated by the specific interaction with bacterially expressed C/EBP protein. Box B bearing the CCAAT sequence binds the ubiquitous factor NFY. Surprisingly, Box A is able to bind two liver enriched factors, namely HNF1 and HNF3. However, in the context of the intact promoter, as shown by footprinting competition experiments, HNF3 binds solely to this sequence. HNF3, but not HNF1 is a transcriptional activator as demonstrated in the in vitro transcription assay.

Expression of the rat aldolase B gene: a liver-specific proximal promoter and an intronic activator

The nature and location of the cis-acting DNA sequences regulating expression of the rat aldolase B gene has been investigated. Two liver-specific DNAse I hypersensitive sites were detected, one located just upstream from the cap site, the second in the middle of the first, 4.8-kbp-long, intron. A fragment of 190 bp 5' to the cap site behaved as a tissue-specific but weak core promoter: it directed a detectable reporter gene expression in the Hep G2 cells and hepatocytes, but not in fibroblasts. The tissue-specific expression was stimulated at least 16 fold when constructs contained the entire first intron. The intronic activating sequences could be ascribed to an inner 2 kbp fragment in which the downstream liver-specific DNAse I hypersensitive site was located.

[Predominant position of impacted lower third molars]

This research tries to establish the predominant position of the included mandibular third molar giving emphasis to the surgical planning. The results were in agreement to that in world literature.

Molecular analysis of aldolase B genes in hereditary fructose intolerance

The molecular basis of hereditary fructose intolerance (HFI) was studied in 50 subjects (41 pedigrees, 82 apparently independent mutant alleles of aldolase B) by direct analysis of aldolase B genes amplified by means of the polymerase chain reaction. The mutation A149P (ala 149----pro) was found in 67% of alleles but was significantly more common in patients from northern than from southern Europe. Two other point mutations of aldolase B were identified. A174D (C----A; ala 174----asp) was found in subjects from Italy, Switzerland, and Yugoslavia (overall frequency 16%) but not in those from the United Kingdom, France, or the United States. L288 delta C carried a single base-pair deletion causing frameshift at codon 288 and was restricted to Sicilian subjects. By testing for these mutations in amplified DNA with a limited panel of allele-specific oligonucleotides, more than 95% of HFI patients will be susceptible to genetic diagnosis.

Characterization of three optional promoters in the 5' region of the human aldolase A gene

We undertook cloning and sequencing of the 5' portion of the human aldolase A gene to elucidate the mechanisms that govern synthesis of its different mRNAs. The sequenced gene is the only active gene in human-rodent fibroblastic somatic hybrids, while the other aldolase A-related sequences are inactive. S1 mapping and primer extension analysis enabled us to demonstrate that three promoter regions were implicated in the initiation of different aldolase A mRNAs, differing only in their 5' non-coding extremities. A distal promoter, N (non-specific), governs the synthesis of a 5' non-coding region of 142 bases composed of two exons, N1 and N2, which are found in a variety of tissues. A median promoter, M (muscle), is only active in skeletal muscle, and initiates the transcription by a 5' non-coding exon of 45 bases. Finally, a proximal promoter, H (housekeeping), contained in a "G + C-rich island", permits transcription of three colinear mRNAs containing 172, 126 or 112 bases of 5' non-coding sequence; their expression seems ubiquitous. These three promoters are arranged in 1.5 X 10(3) base-pairs of DNA. Homologies between rat and human genomic sequences and the absence of homology between promoters or 5' non-coding exons of the same species exclude a recent duplication of the promoter regions.

Nucleotide sequence of a cDNA clone for human aldolase B

Two specific clones for human aldolase B were isolated from a human liver cDNA library using a rat aldolase B cDNA probe. The clones were identified by positive hybridization-selection and one of them was sequenced. The 127 C-terminal residues of the human protein were deduced from this nucleotide sequence analysis. They showed 92% homology with the corresponding previously published amino-acid sequence of rat liver aldolase B.

Purification of human liver uridylyl transferase and comparison with the erythrocyte enzyme

Uridylyl transferase (UDP glucose: alpha-D-galactose 1 phosphate uridylyl transferase, EC 2.7.7.12) has been purified 1350-fold from human liver to complete homogeneity. The purification procedure involved ammonium sulfate fractionation, batch treatment, chromatography on DEAE-cellulose, hexylagarose and hydroxylapatite. The specific activity of the homogeneous enzyme was 27 units/mg protein. The liver enzyme was compared to the red cell enzyme previously purified by us. The liver enzyme was similar to the red cell enzyme with respect to subunit molecular weight, kinetic studies and immunological properties. Differences in electrophoretic behaviour were found: the liver transferase has a more basic pI (between 5.5 and 5.8) than that of the erythrocyte enzyme (pI between 5.0 and 5.45). It is very likely that the liver uridylyl transferase and the red blood cell transferase are the same enzymes with post-translational modifications.

Isozyme differentiation of aldolase and pyruvate kinase in fetal, regenerating, preneoplastic, and malignant rat hepatocytes during culture

Aldolase and pyruvate kinase isozymes were investigated in cultured hepatocytes from fetal, regenerating, and 2-acetyl-aminofluorene-fed rat liver as well as in some epithelial liver cell lines. Our results show that: (a) cell proliferation and prolonged expression of specific isozymes were found only in cultured hepatocytes from 17-day old fetuses; (b) the fetal type of pyruvate kinase expressed in regenerating and carcinogen-treated liver was temporarily lost only in cultured hepatocytes from regenerating liver; (c) the adult type of aldolase and pyruvate kinase was absent in one epithelial cell line derived from a carcinogen-treated liver and in the hepatoma tissue cell (HTC) line but was found in the Faza clone of the Reuber H35 cell line during the 50 first passages in vitro; and (d) the isozyme pattern of pyruvate kinase was always more strongly shifted than that of aldolase. The observations suggest that: (a) hepatocytes from carcinogen-treated liver exhibit the same lack of ability to proliferate in primary culture as normal adult hepatocytes; (b) adult hepatocytes can produce fetal isozymes without prior cell division; (c) pyruvate kinase is a stronger marker of dedifferentiation (retrodifferentiation) than aldolase; and (d) regulatory processes of isozyme expression are different during ontogenesis, regeneration, and hepatocarcinogenesis.

Gene dosage effect for GALT in 9p trisomy and in 9p tetrasomy with an improved technique for GALT determination

A new born male and a three-year-old female with various dysmorphic features were both found to have to have a supernumerary chromosome. Clinical and cytogenetic findings confirmed the existence of a pure de novo 9p tetrasomy in the first case and a pure de novo 9p trisomy in the second case. Gene dosage effects were demonstrated for galactose-1-phosphate uridyltransferase GALT (EC 2.7.7.12) using an improved method for the assay of this enzyme in red blood cells. These findings are in agreement with previous results on similar cases and therefore confirm the assignment of the locus for GALT to 9p.

Purification and characterization of human erythrocyte uridylyl transferase

A new method for the purification of human erythrocyte uridylyl transferase (UDPglucose: alpha-D-galactose-1-phosphate uridylyltransferase EC 2.7.7.12) is described. It consists of a hydrophobic purification step associated with hydroxyapatite chromatography and provided for the first time a purification of more than 45 000-fold with a high activity (15 I.U/mg) and a yield of 32%. We show that the enzyme is a dimer and has a molecular weight of 88 000. It can be resolved into three bands by isoelectric focusing with an apparent pI between 5.0 and 5.4. It could be shown by steady-state initial rate measurements that the interconversion of the two substrates of human transferase (Gal-1-P and UDP-glucose) follows ping-pong bi-bi kinetics, with Km values of 0.2 and 0.065 mM, respectively.

Isoelectrofocusing of erythrocyte galactose 1 phospho uridyl transferase in a family with both galactosemia and Duarte variants

A family with the presence of the genes for both galactosemia and the Duarte variant is described. Galactose 1 phospho uridyl transferase has been studied not only by electrophoresis on starch gel, but also by isoelectro-focusing on thin-layer acrylamide. Normal and variant transferases were resolved into three bands, the isoelectric point of which was between 5.40 and 5.10 for the normal subjects, and between 5.25 and 4.95 for subjects with the Duarte variant.

Prenatal diagnosis of galactosemia

We have monitored 3 pregnancies at risk for galactosemia by deficiency in Galactose-1-Phospho uridyl transferase. Galactosemia was diagnosed in the 1st case; heterozygoty in the 2nd, and a "double heterozygoty" in the 3rd. The latter is the first example of such a diagnosis. Post natal confirmation was obtained in the three cases. Arguments are given for the usefulness of this prenatal diagnosis.

Isoelectrofocusing of aldolase B from normal human livers and from livers with hereditary fructose intolerance

By isoelectrofocusing in thin-layer acrylamide-ampholine gel, normal human aldolase B has been resolved into 5 bands. Moreover we were able to specifically stain (after isoelectrofocusing) the mutated aldolase B in livers with hereditary fructose intolerance, and to show that only the 3 most anodic bands are seen. Some different hypotheses are discussed to account for the microheterogeneity of the normal aldolase B, and for the different isoelectrofocusing pattern found in livers with hereditary fructose intolerance.

Aldolase B in the liver of senescent rats

The process of enzymatic aging was studied in livers of adult and senescent rats for aldolase B. No "cross-reacting material" was found in livers of 27 to 30-month-old rats, estimated by the ratio aldolase activity-antigen amount. The activity towards the two substrates of aldolase, fructose 1,6-diphosphate and fructose 1-phosphate did not vary in senescent animals. Moreover, other physico-chemical properties of the enzyme such as thermal inactivation, immunological reactivity and Michaelis constant remain unchanged. These results provide arguments against the occurrence of errors in protein synthesis as a cause of aging.

Aging and accuracy of protein synthesis in man: search for inactive enzymatic cross-reacting material in granulocytes of aged people

Enzyme activities and immunological reactivities of seven different enzymes have been assayed in the polymorphonuclear leukocytes from 10 newborns, 10 aged (over 80 years old) and 10 young adults (20-30 years old). Polymorphonuclears have been chosen because both in the newborns, and in the aged people, they are young cells whose life span is a few hours only. Five cytoplasmic enzymes have been immunologically studied by means of monospecific antienzyme sera: leukocyte pyruvate kinase by immunoinactivation, glucose-6-phosphate dehydrogenase and glucose phosphate-isomerase by electroimmunodiffusion, lactic dehydrogenase (muscle-type) by radial immunodiffusion. Two lysosomal enzymes (alpha-mannosidase and beta-glycuronidase) have been titrated immunologically with the same polyvalent antihuman leukocyte rabbit serum. Small but significant differences in activity were observed for several of the enzymes. By contrast, no significant difference was found, for any of the seven enzymes, as regards the ratio enzyme activity/immunological reactivity, between newborns, young adults and aged people. These results of not support the theory that a decreased accuracy of the protein synthesis machinery is responsible for aging and death. By contrast, the authors emphasize that the enzyme abnormalities reported by various authors in old animals or in old fibroblast cultures closely resemble those demonstrated to be "post-translational modifications" in the case of human glucose-6-phosphate dehydrogenase.

Modification of pyruvate kinase isozymes in prolonged primary cultures of adult rat hepatocytes

Pyruvate kinase isozymic changes were studied in the adult hepatocyte cultures, by electrophoretic, kinetic and immunological methods. We were able to maintain parenchymal cells from normal adult rat liver in non-proliferating monolayer cultures up to 10 days. Hepatocytes appeared to contain a dominant PK I type up to 4-5 days of culture. After day 5, PK III type was regularly present with PK I and after 7 days PK III type was always the only isozyme detected in culture. It must be pointed out that, by the Ouchterlony method and sometimes by electrophoresis, concentrated extracts from freshly isolated hepatocytes or starting hepatocyte cultures did also contain Pyruvate kinase PK III type. These results suggest that Pyruvate kinase III is present but partly repressed in the adult parenchymal cells and becomes derepressed in culture.