CT prognostic signs of postoperative complications in emergency surgery for acute obstructive colonic cancer

PURPOSE

To identify CT prognostic signs of poor outcomes in acute obstructive colonic cancer (AOCC).

METHODS

Demographic, clinical, laboratory, radiological and surgical data of 65 consecutive patients with AOCC who underwent emergency surgery were analyzed. CT exams were reviewed to assess diameters of cecum, ascending, transverse, descending, and sigmoid proximal to the tumor; colon segments' CD/L1-VD ratios, continence of the ileocecal valve, small bowel overdistension, presence of small bowel feces sign and cecal pneumatosis. Post Operative complications (PO), according to the Clavien-Dindo classification, were analyzed.

RESULTS

Gender, age and location of the tumor were not predictive factors of complications. Among laboratory exams, CRP was the most important predictive value of PO (OR 8.23). A cecum distension ≥ 9 cm represented the critical diameter beyond which perforation and cecal necrosis were found at surgery. Cecal pneumatosis at CT was correlated with cecal necrosis at surgery in < 50% of patients. Pre-operative transverse colon CD/L1-VD ratio ≥ 1.43 and descending colon CD/L1-VD ratio ≥ 1.31 were associated with the development of PO (grade ≥ III-V). PO (grade ≥ III-V) occurred in 18/65 patients.

CONCLUSION

Postoperative complications in emergency surgery of AOCC were not related to the age, sex and tumor's location. Preoperative PCR values (≥ 2.17) predict the development of postoperative complications. CT resulted a valid diagnostic tool to identify patients at higher risk of complications: a CD/L1-VD ratios with cut-off values of 1.43 (transverse) and 1.31 (descending) predicted major complications (grade ≥ III-V) and a cecum distension ≥ 9 cm represented the critical diameter beyond which perforation occurred in > 84% of patients.

Kiwifruit Act d 11 is the first member of the ripening-related protein family identified as an allergen

BACKGROUND

Kiwifruit is an important cause of food allergy. A high amount of a protein with a molecular mass compatible with that of Bet v 1 was observed in the kiwifruit extract.

OBJECTIVE

To identify and characterize kirola, the 17-kDa protein of green kiwifruit (Act d 11).

METHODS

Act d 11 was purified from green kiwifruit. Its primary structure was obtained by direct protein sequencing. The IgE binding was investigated by skin testing, immunoblotting, inhibition tests, and detection by the ISAC microarray in an Italian cohort and in selected Bet v 1-sensitized Austrian patients. A clinical evaluation of kiwi allergy was carried out.

RESULTS

Act d 11 was identified as a member of the major latex protein/ripening-related protein (MLP/RRP) family. IgE binding to Act d 11 was shown by all the applied testing. Patients tested positive for Act d 11 and reporting symptoms on kiwifruit exposure were found within the Bet v 1-positive subset rather than within the population selected for highly reliable history of allergic reactions to kiwifruit. Epidemiology of Act d 11 IgE reactivity was documented in the two cohorts. IgE co-recognition of Act d 11 within the Bet v 1-like molecules is documented using the microarray IgE inhibition assay.

CONCLUSIONS

Act d 11 is the first member of the MLP/RRP protein family to be described as an allergen. It displays IgE co-recognition with allergens belonging to the PR-10 family, including Bet v 1.

Structural basis of the destabilization produced by an amino-terminal tag in the β-glycosidase from the hyperthermophilic archeon Sulfolobus solfataricus

We have previously shown that the major ion-pairs network of the tetrameric beta-glycosidase from the hyperthermophilic archeon Sulfolobus solfataricus involves more than 16 ion-pairs and hydrogen bonds between several residues from the four subunits and protects the protein from thermal unfolding by sewing the carboxy-termini of the enzyme. We show here that the amino-terminal of the enzyme also plays a relevant role in the thermostabilization of the protein. In fact, the addition of four extra amino acids at the amino-terminal of the beta-glycosidase, though not affecting the catalytic machinery of the enzyme and its thermophilicity, produced a faster enzyme inactivation in the temperature range 85-95 degrees C and decreased the Tm of the protein of 6 degrees C, measured by infrared spectroscopy. In addition, detailed two-dimensional IR correlation analysis revealed that the quaternary structure of the tagged enzyme is destabilized at 85 degrees C whilst that of the wild type enzyme is stable up to 98 degrees C. Molecular models allowed the rationalization of the experimental data indicating that the longer amino-terminal tail may destabilize the beta-glycosidase by enhancing the molecular fraying of the polypeptide and loosening the dimeric interfaces. The data support the hypothesis that fraying of the polypeptide chain termini is a relevant event in protein unfolding.

Pectin methylesterase inhibitor

Pectin methylesterase (PME) is the first enzyme acting on pectin, a major component of plant cell wall. PME action produces pectin with different structural and functional properties, having an important role in plant physiology. Regulation of plant PME activity is obtained by the differential expression of several isoforms in different tissues and developmental stages and by subtle modifications of cell wall local pH. Inhibitory activities from various plant sources have also been reported. A proteinaceous inhibitor of PME (PMEI) has been purified from kiwi fruit. The kiwi PMEI is active against plant PMEs, forming a 1:1 non-covalent complex. The polypeptide chain comprises 152 amino acid residues and contains five Cys residues, four of which are connected by disulfide bridges, first to second and third to fourth. The sequence shows significant similarity with the N-terminal pro-peptides of plant PME, and with plant invertase inhibitors. In particular, the four Cys residues involved in disulfide bridges are conserved. On the basis of amino acid sequence similarity and Cys residues conservation, a large protein family including PMEI, invertase inhibitors and related proteins of unknown function has been identified. The presence of at least two sequences in the Arabidopsis genome having high similarity with kiwi PMEI suggests the ubiquitous presence of this inhibitor. PMEI has an interest in food industry as inhibitor of endogenous PME, responsible for phase separation and cloud loss in fruit juice manufacturing. Affinity chromatography on resin-bound PMEI can also be used to concentrate and detect residual PME activity in fruit and vegetable products.

Hagfish hemoglobins: structure, function, and oxygen-linked association

Cyclostomes, hagfishes and lampreys, contain hemoglobins that are monomeric when oxygenated and polymerize to dimers or tetramers when deoxygenated. The three major hemoglobin components (HbI, HbII, and HbIII) from the hagfish Myxine glutinosa have been characterized and compared with lamprey Petromyzon marinus HbV, whose x-ray crystal structure has been solved in the deoxygenated, dimeric state (Heaslet, H. A., and Royer, W. E., Jr. (1999) Structure 7, 517-526). Of these three, HbII bears the highest sequence similarity to P. marinus HbV. In HbI and HbIII the distal histidine is substituted by a glutamine residue and additional substitutions occur in residues located at the deoxy dimer interface of P. marinus HbV. Infrared spectroscopy of the CO derivatives, used to probe the distal pocket fine structure, brings out a correlation between the CO stretching frequencies and the rates of CO combination. Ultracentrifugation studies show that HbI and HbIII are monomeric in both the oxygenated and deoxygenated states under all conditions studied, whereas deoxy HbII forms dimers at acidic pH values, like P. marinus HbV. Accordingly, the oxygen affinities of HbI and HbIII are independent of pH, whereas HbII displays a Bohr effect below pH 7.2. HbII also forms heterodimers with HbIII and heterotetramers with HbI. The functional counterparts of heteropolymer formation are cooperativity in oxygen binding and the oxygen-linked binding of protons and bicarbonate. The observed effects are explained on the basis of the x-ray structure of P. marinus HbV and the association behavior of site-specific mutants (Qiu, Y., Maillett, D. H., Knapp, J., Olson, J. S., and Riggs, A. F. (2000) J. Biol. Chem. 275, 13517-13528).

Hemoglobin of the Antarctic fishes Trematomus bernacchii and Trematomus newnesi: structural basis for the increased stability of the liganded tetramer relative to human hemoglobin

Hemoglobins extracted from fishes that live in temperate waters show little or no dissociation even in the liganded form, unlike human hemoglobin (HbA). To establish whether cold adaptation influences the tendency to dissociate, the dimer-tetramer association constants (L(2,4)) of the carbonmonoxy derivatives of representative hemoglobins from two Antarctic fishes, Trematomus newnesi (Hb1Tn) and Trematomus bernacchii (Hb1Tb), were determined by analytical ultracentrifugation as a function of pH in the range 6.0-8.6 and compared to HbA. HbA is more dissociated than fish hemoglobins at all pH values and in particular at pH 6.0. In contrast, both fish hemoglobins are mostly tetrameric over the whole pH range studied. The extent of hydrophobic surface area buried at the alpha(1)beta(2) interface upon association of dimers into tetramers and the number of hydrogen bonds formed are currently thought to play a major role in the stabilization of the hemoglobin tetramer. These contributions were derived from the X-ray structures of the three hemoglobins under study and found to be in good agreement with the experimentally determined L(2,4) values. pH affects oxygen binding of T. bernacchii and T. newnesi hemoglobins in a different fashion. The lack of a pH effect on the dissociation of the liganded proteins supports the proposal that the structural basis of such effects resides in the T (unliganded) structure rather than in the R (liganded) one.

Molecular modelling of Trematomus newnesi Hb 1: insights for a lowered oxygen affinity and lack of root effect

Three-dimensional structural models of the hemoglobin (Hb 1) of the Antarctic fish Trematomus newnesi were built by homology modelling, using as template the X-ray crystallographic structures of Trematomus (previously named Pagothenia) bernacchii Hb 1, both in R and T state. The Hbs of these two fishes, although showing remarkably different oxygen binding properties, differ only by 4 residues in the alpha chain (142 aa) and 10 residues in the beta chain (146 aa). T. newnesi Hb1 R-state model, essentially performed as a quality control of the adopted modelling procedure, showed a good correspondence with the crystallographic one. Modelling of T. newnesi Hb1 in the T state was performed taking into account that the proton uptake by aspartate residues, proposed to be responsible for half of the Root effect in T. bernacchii Hb 1 (showing sharp pH dependent oxygen affinity and T-state overstabilization at low pH, i. e. Bohr and Root effect), does not occur in T. newnesi Hb1 (having nearly pH-independent lower oxygen affinity). Comparison with the template structure (submitted to the same minimization procedure) indicates that, in T. newnesi Hb1 T-state model, the substitution of Ile for Thr in 41 C6, in central position of the switch region, induces at the alpha(1)beta(2) interface structural modifications able to hamper the protonation. Similar modifications are also found in T. bernacchii Hb 1 modelled in the T state with the single substitution Thr-->Ile in 41alpha. These models also suggest that the lower oxygen affinity observed in T. newnesi Hb1 is related to structural differences at the alpha(1)beta(2) interface leading to a more stable low-affinity T state. Proteins 2000;39:155-165.

Crystal structure of Trematomus newnesi haemoglobin re-opens the root effect question

As new structural data have become available, somewhat contrasting explanations of the Root effect in fish haemoglobins (Hb) have been provided. Hb 1 of the Antarctic fish Trematomus newnesi has a nearly pH-independent oxygen affinity, in spite of 95 % sequence identity with Hb 1 of Trematomus (previously named Pagothenia) bernacchii that has a strong Root effect. Here, the 2.2 A R-state structure of Trematomus newnesi Hb 1 is presented. The structure is similar to that of Root effect fish Hbs from Spot and T. bernacchii, suggesting that the differences in the pH dependence cannot be related to the modulation of the R-state. In comparison to T. bernacchii Hb 1, the role of the three mutations Thr41 (C6)alpha-->Ile, Ala97 (G3)alpha-->Ser and His41 (C7)beta-->Tyr at the alpha1beta2-interface is discussed.

The hemoglobin system of Pleuragramma antarcticum: correlation of hematological and biochemical adaptations with life style

The hematological properties and the oxygen-transport system of the antarctic fish Pleuragramma antarcticum were investigated. Most blood parameters are at the lower end of the range of values known for red-blooded antarctic fish, suggesting a link with the sluggish mode of life of this species. P. antarcticum is the only species of the family Nototheniidae and of the suborder Notothenioidei having three major hemoglobins, which were isolated and fully characterized. The complete amino acid sequence of the alpha- and beta-globin chains was determined. The three hemoglobins showed strong Bohr and Root effects, and their oxygen-binding properties were differently regulated by temperature. None of the three hemoglobins of P. antarcticum can be considered as evolutionary (or larval) remnants. Therefore, this oxygen-transport system is one of the most specialized ever found in fish. The data suggest a strong relationship between hematological/biochemical adaptation and life style.

The hemoglobin system of Antarctic and non-Antarctic notothenioid fishes

Studies of the hemoglobin system of fish of the suborder Notothenioidei have been extended to non-Antarctic species of Pseudaphritis urvillii and Notothenia angustata. The two species belong to families that were the first to diverge within the suborder. The degree of amino acid sequence identity with Antarctic notothenioids and other non-Antarctic fish species is analyzed with respect to phyletic and ecological diverence.

Molecular evolution of hemoglobins of Antarctic fishes (Notothenioidei)

Amino acid sequences of alpha- and beta-chains of human hemoglobin and of hemoglobins of coelacanth and 24 teleost fish species, including 11 antarctic and two temperate Notothenioidei, were analyzed using maximum parsimony. Trees were derived for the alpha- and beta-chains separately and for tandemly arranged sequences, using the human and coelacanth sequences as outgroups in all analyses. The topologies of the trees of the alpha- and beta-chains are highly congruent and indicate a specific pattern of gene duplications and gene expression of teleost hemoglobins which has not yet been investigated into more detail. The Notothenioid fish generally contain a single major hemoglobin and often a second minor component. The alpha- and beta-chains of the major components form a monophyletic group in all investigated trees, with the nonantarctic Pseudaphritis as their sister taxon. The minor chains also are a monophyletic group and form an unresolved cluster with the major chains and the hemoglobins of tuna and red gurnard. The Notothenioid families Nototheniidae and Bathydraconidae appear to be paraphyletic.

Proton-linked subunit kinetic heterogeneity for carbon monoxide binding to hemoglobin from Chelidonichthys kumu

The pH dependence of CO binding kinetics to Chelidonichthys kumu hemoglobin (Hb) and human adult Hb has been investigated between pH 2.0 and 9.0 at 20 degrees C. For both Hbs, CO binding kinetics is characterized by two proton-linked transitions, with different pKa values for alpha- and beta-chains in C. kumu Hb, leading to a relevant functional kinetic heterogeneity at most pH values. On the other hand, in human adult Hb the CO binding does not display a functional heterogeneity. Lowering the pH from 9 to 6 brings about a decrease of the CO binding rate constants, to a different extent for human adult Hb and the two chains of C. kumu Hb. Further lowering the pH from 6 to 2 induces an enhancement of CO binding rate constants, probably related to the protonation of proximal HisF8 Nepsilon atom and the cleavage (or severe weakening) of the HisF8-Fe bond. The presence of physiological concentrations of ATP (approximately 3 mM) affects the pH dependence of CO binding kinetics to C. kumu. Moreover, the effect of temperature (between 8 degrees C and 38 degrees C) on CO binding kinetics has been investigated in the absence of ATP at different pH values. These results allow to interpret the functional kinetic heterogeneity of C. kumu Hb on the basis of different regulatory aspects in the alpha- and beta-subunits, as suggested by structural considerations.

The unique hemoglobin system of Pleuragramma antarcticum, an antarctic migratory teleost. Structure and function of the three components

Pleuragramma antarcticum (suborder Notothenioidei, family Nototheniidae) is the most abundant fish in the antarctic shelf. This pelagic species has a circum-antarctic distribution and is characterized by spawning migration. This species displays the highest multiplicity of major hemoglobins (three); the other notothenioids have a single one (except one species, having two) with relatively low oxygen affinity regulated by pH and organophosphates. The hemoglobins of P. antarcticum display strong Bohr and Root effects; however, they reveal important functional differences in subunit cooperativity and organophosphate regulation and, above all, in the response of oxygenation to temperature. Despite the substitution ValbetaE11 --> Ile found in Hb 2, which decreases the affinity in human mutants, the hemoglobins have similar oxygen affinity, higher than that of the other notothenioids. Hb 1 has the alpha chain in common with Hb 2 and the beta in common with Hb 3. The amino acid sequence of all four chains has been established. Thus the hematological features of P. antarcticum differ remarkably from those of antarctic notothenioids. This unique and sophisticated oxygen transport system may adequately meet the requirements of the unusual mode of life of this fish.

Molecular characterization of the functionally distinct hemoglobins of the Antarctic fish Trematomus newnesi

Antarctic fish of the family Nototheniidae usually have a single major hemoglobin (Hb 1), often a second, minor component (Hb 2, about 5% of the total), and traces of another component (Hb C, less than 1%). These are functionally similar Bohr and Root effect hemoglobins. All species of other highly endemic fish families so far investigated also have one single major hemoglobin. The hematological features of the nototheniid Trematomus newnesi are remarkably different. It is the only Antarctic species in which Hb 1 and Hb 2 display only a very weak Bohr effect and no Root effect. Perhaps consequentially, Hb C (the only component showing regulation of oxygen binding by protons and other effectors) is not present in traces but accounts for 20-25% of the total. The primary structure of the three hemoglobins of T. newnesi and of Root effect HbC present in trace amounts in another nototheniid (Pagothenia bernacchii) is discussed in relationship with oxygen binding and in terms of molecular and stereochemical models. The hemoglobin multiplicity, the oxygen binding features of Hb 1 and Hb 2, and the presence of functionally distinct components, thus reveal that the oxygen transport of T. newnesi has unique characteristics.

A polymerising Root-effect fish hemoglobin with high subunit heterogeneity. Correlation with primary structure

The blood of the teleost Chelodonichthys kumu, living in the temperate waters of New Zealand, contains a single hemoglobin. The complete amino acid sequence of the alpha and beta chain has been established. The presence of a reactive Cys in the external position beta CD8(49) causes polymerisation through intermolecular disulfide bridges between beta chains, with no alteration of functional features. C. kumu Root-effect hemoglobin displays very low or no subunit co-operativity in the physiological pH range. Kinetic experiments on the oxygen dissociation and binding of carbon monoxide show a marked, pH-dependent functional heterogeneity of the two chains, which contributes to the observed reduction of co-operativity. In contrast, kinetic heterogeneity was not observed in the process of CO dissociation, indicating that functional differences between the subunits are detectable only for the dynamic ligand association pathway. The allosteric effector, ATP, seems to increase the pKa of the proton-linked effect on the slow-reacting subunit, affecting the quaternary equilibrium through stabilisation of the T state at lower pH, rather than enhancing the functional heterogeneity itself. In position E11 of both chains, Val (usually present at the distal side of the heme), is substituted by Ile. Although this residue has been shown not to significantly alter ligand binding to the alpha chain, to some extent it can perturb the access of oxygen to the beta chain. Thus, this substitution may be the main reason for subunit functional heterogeneity.

The hemoglobins of Notothenia angustata, a temperate fish belonging to a family largely endemic to the Antarctic Ocean

The blood of the teleost Notothenia angustata contains a major hemoglobin (Hb 1, over 95% of the total), accompanied by a minor component (Hb 2). The two hemoglobins have identical beta chains and differ in their alpha chains. The primary structure of both hemoglobins has been established through the elucidation of the complete amino acid sequence of the three chains. The study of the oxygen-binding properties shows that Hb 1 displays the Bohr and Root effects and has high affinity for organic phosphates. N. angustata belongs to the family Nototheniidae, suborder Notothenioidei. Unlike the vast majority of nototheniid species, which live in isolation in the Antarctic Ocean and have developed cold adaptation, N. angustata inhabits the waters of southern New Zealand and is not cold adapted. Although some hematological parameters typically favour oxygen transport in a temperate environment, the hemoglobin multiplicity and structural and functional features closely resemble those of the Antarctic species of the same family and suborder. Thus, N. angustata may be considered as a link between temperate and Antarctic habitats. The hypothetical separation history of N. angustata from the Antarctic species of the same family is discussed in the light of the present findings.

Apparent deficiency of metallothionein in the liver of the Antarctic icefish Chionodraco hamatus. Identification and isolation of a zinc-containing protein unlike metallothionein

1. A zinc-binding protein has been isolated and purified from the liver of the icefish Chionodraco hamatus. 2. The icefish Zn-protein has characteristics distinct from those of metallothionein. 3. The amino acid composition shows a low content of cysteine and a high content of glutamate and aspartate. 4. No metallothionein has been detected in the extracts from icefish liver.

Haemoglobin of the antarctic fish Pagothenia bernacchii. Amino acid sequence, oxygen equilibria and crystal structure of its carbonmonoxy derivative

The Antarctic fish Pagothenia bernacchii has one major haemoglobin, Hb1 (over 95% of the total blood content). Hb1 has a strong alkaline Bohr effect and at low pH exhibits the reduced ligand affinity and co-operativity that comprise the Root effect. We have determined the complete amino acid sequence of P. bernacchii Hb1 and also the structure of its carbonmonoxy derivative by X-ray crystallography, to a resolution of 2.5 A. The crystallographic R-factor of the refined structure is 18%. The three-dimensional structure of this fish haemoglobin is similar to that of human haemoglobin A, with a root-mean-square difference in main-chain atom positions of 1.4 A after superimposition of the two structures, despite only 48% homology of their amino acid sequences (including insertion of a single residue in the CD region of the fish alpha-chain). Large structural differences occur only at the N and C termini of both the alpha- and beta-chains. Neither these nor other smaller structural differences provide any obvious explanation of the Root effect of this or other fish haemoglobins.

The amino acid sequence of the alpha chain of HB 2 completes the primary structure of the hemoglobins of the Antarctic fish Notothenia coriiceps neglecta

1. The blood of Notothenia coriiceps neglecta (a cold-adapted notothenioid fish, widely distributed in Antarctic waters, and characterized by a relatively low content of erythrocytes and hemoglobin), contains two hemoglobin components, Hb 1 and Hb 2; the amino acid sequences of the beta chain of Hb 1 and Hb 2 are identical. 2. The amino acid sequence of the alpha chain of Hb 2 has been established, thus completing the elucidation of the primary structure of the two hemoglobins.

Hemoglobin from the antarctic fish Notothenia coriiceps neglecta. Amino acid sequence of the beta chain

1. Notothenia coriiceps neglecta is a cold-adapted notothenioid teleost, widely distributed in the Antarctic waters. 2. In comparison with fishes from temperate waters, the blood of this teleost contains a reduced number of erythrocytes and concentration of hemoglobin; the erythrocytes contain two hemoglobins, Hb1 and Hb2, respectively accounting for approximately 90, and 5% of the total. 3. The two components differ by the alpha chain; the amino acid sequence of the beta chain in common to the two hemoglobins has been established, thus completing the elucidation of the primary structure of the major component Hb 1.

The amino acid sequence of the alpha- and beta-chains of the two hemoglobins of the Antarctic fish Notothenia coriiceps neglecta

The blood of the Antarctic fish Notothenia coriiceps neglecta contains two hemoglobins, Hb 1 and Hb 2, which have a beta-chain in common. We have elucidated the primary structure of the beta-chain (146 residues) and of the alpha-chains (142 residues) of the two hemoglobins. The two alpha-chains differ from each other by 51 residues; in comparison with globin sequences of temperate fishes, the alpha-chain of Hb 1 is more similar to that of bluefin tuna than to the alpha-chain of Hb 2 of the same species.

Hemoglobin from the Antarctic fish Notothenia coriiceps neglecta. 2. Amino acid sequence of the alpha chain of Hb1

The complete amino acid sequence of the alpha chain of the main hemoglobin of the Antarctic fish Notothenia coriiceps neglecta (family Nototheniidae) has been determined. It consists of 142 residues; an acetylated seryl residue is at the amino terminal. The molecular mass is 15,519 Da. In comparison with alpha-chain sequences of non-Antarctic poikilothermic fish hemoglobins, the homology appears to be significantly lower than that existing among the latter species. A higher homology has been found with the alpha-chain sequence of the non-poikilothermic bluefin tuna.

Hemoglobin from the Antarctic fish Notothenia coriiceps neglecta. 1. Purification and characterisation

Antarctic fishes live at a constant temperature of -1.8 degrees C, in an oxygen-rich environment. In comparison with fishes that live in temperate or tropical waters, their blood contains less erythrocytes and hemoglobin. A study was initiated on the structure and function of Antarctic fish hemoglobin. The erythrocytes of the Antarctic benthic teleost Notothenia coriiceps neglecta, of the family Nototheniidae, have been shown to contain two hemoglobins, accounting for about 90% and 5% of the total content. These hemoglobins have been isolated, and obtained in crystalline form. They are tetramers and contain two pairs of globin chains. The globin chains of each hemoglobin have been purified and characterised. The two hemoglobins appear to have one of the two globin chains in common. The Root and Bohr effects have been investigated in erythrocytes, 'stripped' hemolysates and pure hemoglobins, indicating that the functional properties are finely regulated by pH and allosteric effectors.

Open heart surgery with factor VII deficiency

A case with marked factor VII deficiency, undergoing open heart surgery for atrial myxoma, is reported. The syndrome was unknown to the patient and only pre-operative routine coagulation studies showed a low prothrombin activity (22%). Further investigations revealed a severe factor VII deficiency. The operation was carried out under factor VII concentrate administration and no bleeding complication occurred.

Combined factor V and factor VII deficiency. Report of a case with a record on combined defects and considerations on the relevance of partial deficiency of coagulation factors

A patient suffering from cardiochalasia was found to be partially deficient in both coagulation factors V and VII. No bleeding tendency had been noticed. A family study showed that the father had factor VII deficiency with normal factor V, while the mother and 2 sisters had a reduced level of factor V and normal factor VII. Thus, the combined deficiency was due to chance association of two distinct independently segregating genetic defects. While a number of combinations of coagulation factor deficiency have been previously described, this, to be best of our knowledge, is the first instance of combined deficiency of factor V and VII reported so far.

Defects in DNA and globin messenger RNA in homozygotes for hemoglobin Lepore

Globin messenger RNA (mRNA) isolated from three patients homozygous for hemoglobin Lepore is shown to have a marked reduction of the amount of beta-like globin mRNA (Lepore-globin mRNA sequences) compared with alpha-globin mRNA by molecular hybridization. The relative amounts of alpha- and Lepore mRNA are similar to the amounts of alpha- and Lepore globin synthesized in intact cells and by isolated mRNA in a cell-free system. It is also demonstrated that Lepore-globin mRNA can completely hybridize to full-length or nearly full-length beta-globin specific complementary DNA and protect it from nuclease digestion, indicating close homology between the delta-mRNA sequences present in Lepore mRNA and the beta-complementary-DNA probe. We have also quantitated the numbers of beta-like globin gene sequences in genomic Lepore DNA by molecular hybridization and demonstrated a reduction in their number consistent with the Lepore gene being a delta beta-gene fusion product.