Comparison of the immune response against polio peptides covalently-surface-linked to and internally-entrapped in liposomes

The adjuvanticity of liposomes on two different modes of presentation of polio virus subunit peptides was demonstrated by incorporating the poorly immunogenic synthetic polio peptides, W1 and W2, into the internal space of and covalently-linked to the surface of dehydration-rehydration vesicles (DRV). It was found that for both peptides, liposome association in either mode boosted the primary and secondary IgG1 responses against 5 micrograms peptide as compared to controls in which free peptide was administered. Surface-linkage of peptides (both W1 and W2) exhibited an initially more rapid rise in antibody levels, as compared to internal entrapment of the peptides, but elicited no observable secondary response. However, although encapsulated W1 showed a milder primary response when compared to the surface-linked formulation, it later elicited a strong secondary response. These results suggested that it may be advantageous to administer liposomal virus subunit vaccines in both surface-linked and internally entrapped formulations to achieve adequate initial antibody levels followed by an anamnestic response.

A novel positively-charged lipid 1,2-bis(hexadecylcycloxy)-3-trimethyl aminopropane (BisHOP) enhances the adjuvant effect of liposomes on encapsulated tetanus toxoid

A novel positively charged lipid, 1,2-bis(hexadecylcycloxy)-3-trimethylaminopropane-HCl (BisHOP), when incorporated into the bilayers of phosphatidylcholine (PC) and distearoyl phosphatidylcholine (DSPC) dehydration-rehydration vesicles (DRV), was shown to have a powerful effect in enhancing the IgG1 response to tetanus toxoid encapsulated within the liposomes. The adjuvant effect was significantly greater when 20% BisHOP was incorporated as compared to 10% incorporation and to control PC and DSPC DRV. Plain, uncharged DSPC DRV were found to have a greater adjuvant effect than plain PC DRV on the entrapped tetanus toxoid after a single intramuscular injection. Even though antibody levels at 8 weeks post-injection were similar for 20% BisHOP PC and DSPC DRV, the rate of rise of antibody titres was more rapid for 20% BisHOP DSPC than for 20% BisHOP PC DRV. These results suggest that faster and higher titers of antibodies may be obtained by optimal manipulation of the charged and non-charged lipid components of liposomes.

Regions of the T cell receptor alpha and beta chains that are responsible for interactions with CD3

The T cell antigen receptor consists of the Ti alpha/beta heterodimer which recognizes antigen, and the associated CD3 chains, thought to be involved in signal transduction. To understand the nature of the interaction between Ti and CD3, chimeric molecules which included the COOH-terminal segments of Ti alpha or beta linked to the extracellular segment of CD8, were transfected into a mutant T cell deficient in Ti beta chain expression and cell surface CD3. Both chimeric chains were required to express the chimeric Ti and to restore CD3 surface expression. CD8/Ti and CD3 cointernalized and coimmunoprecipitated. Stimulation of the chimeric receptor induced transmembrane signaling events and cell activation. These results demonstrate that the Ti alpha and beta COOH termini containing the transmembrane domains are sufficient for structural and functional coupling of Ti to CD3.

Cytogenetic analysis of 147 cases of non-Hodgkin's lymphoma: non-random chromosomal abnormalities and histological correlations

A prospective cytogenetic study of patients with non-Hodgkin's lymphoma (NHL) presenting to one institution was commenced in 1983 as part of a larger study including histology, immunophenotyping, cytokinetics and survival. 175 patients were studied over 5 years and G-banded karyotypes were successfully obtained in 147. Chromosome abnormalities were detected in 135 cases (92%) with the commonest abnormality being t(14;18)(q32;q21) in 69 cases. Other non-random translocations were much less frequent, i.e. t(11;14) in seven cases and t(8;14) in four cases. Other specific structural changes included partial deletions of 6q (breakpoints ranging within q13-q23), 3q (breakpoints ranging within q21-q27), 1q and 10q22. Chromosome regions highlighted as being frequently involved in structural abnormalities were 11q13-q25, 1p22-p36, 3q21-q27 and 6q13-q23. Several specific recurring breakpoints were identified and these included 14q32, 18q21, 1p36 and 6q21. Frequently occurring numerical abnormalities were gains of chromosomes 3, 7, X and 12. Correlation with histological type showed, as expected, that t(14;18) was present in 89% of follicular lymphoma but also occurred in 30% of diffuse lymphoma. Abnormalities of 11q were correlated with the diffuse histologies as a group, whereas both numerical and structural abnormalities of chromosome 3 correlated with the diffuse large cell lymphoma (DLCL) subtype, and t(11;14) with diffuse small cleaved cell lymphoma (DSCCL). Although not statistically significant, abnormalities of 6q occurred twice as frequently in DLCL than in any other variety. However, several other commonly occurring abnormalities, such as extra copies of chromosomes 7, X, 12 and most of the structural abnormalities of 1p, did not correlate with any histological type. Therefore this large cytogenetic study has confirmed some previously reported correlations between specific chromosome abnormalities and histological subtypes of non-Hodgkin's lymphoma and has also identified some new correlations which may prove useful in the investigation of the biological basis of the disease.

Use of a nasal continuous positive airway pressure mask in the treatment of postoperative atelectasis in aortocoronary bypass surgery

Pulmonary oxygen transfer, defined by PaO2/FIO2, and radiologic presence of atelectasis were measured pre-, intra-, and postoperatively to postoperative day 9 in elective cardiac aortocoronary bypass surgical patients, who were randomly allocated either to receive 18 h PEEP while on the ventilator followed by 12 h of nasal continuous positive airway pressure (nasal CPAP) or to be control subjects. The two groups were comparable in age, sex, forced expiratory volume in 1 sec (FEV1), the ratio of FEV1 over forced vital capacity (FVC), time on pump, units of blood transfused, New York Heart Association grading, and cardiac performance indices. The PaO2/FIO2 was significantly (p less than .05) better from half an hour after extubation until 24 h postextubation in the nasal CPAP group, but was decreased for the remainder of the study in both groups. Incidence of atelectasis/consolidation was not different in both groups during the study period. We conclude that nasal CPAP is well tolerated as a treatment of hypoxemia in the immediate postoperative period of aortocoronary bypass patients. CPAP does not change the course of postoperative atelectasis.

Diurnal rhythms of cortisol, ACTH, and beta-endorphin levels in neonates and adults

To determine whether a diurnal rhythm exists in neonates admitted to neonatal intensive care units where there is continuous artificial lighting and periodic nursing and medical care, plasma cortisol, adrenocorticotropin (ACTH), and beta-endorphin concentrations were measured in two groups of infants and in adult human volunteers. As expected, a diurnal rhythm was seen in adults. A diurnal rhythm was also found for cortisol and endorphin levels in neonates (3 to 4 days postnatally) with minimal stress and in infants who were clinically severely stressed. There was not a significant difference between the morning and afternoon concentrations of ACTH in these infants, but the afternoon concentrations were lower than the morning's, as would be expected. We found that a diurnal rhythm does exist in neonates within the first few days of postnatal life and that the continuous lighting and medical and nursing interventions do not interfere with this rhythm.

Adipose veno-lymphatic transfer for management of post-radiation lymphedema

In a patient who had post-radiation lymphedema after excision of liposarcoma, a method is described that is called adipose veno-lymphatic transfer. The technique involves transferring adipose tissue containing lymphatic vessels that surround the long saphenous vein, from the normal, healthy leg to the irradiated leg, with the creation of an arteriovenous fistula.

The sequence specificity of bleomycin damage in three cloned DNA sequences that differ by a small number of base substitutions

The DNA sequence specificity of the cancer chemotherapeutic agent, bleomycin, has been investigated in three clones of human alpha RI-DNA. The three 340-base pair alpha RI-DNA sequences were almost identical in their nucleotide sequence enabling the study of subtle effects of base substitutions on bleomycin cleavage. By utilizing densitometer scanning and statistical analysis of the degree of bleomycin DNA cleavage, we found 17 significant differences between the three DNA sequences. Eleven of these differences could be attributed to base substitutions close to the dinucleotide cleavage site. However, six of the differences were at positions two or more base pairs from the base substitution sites. The significant differences were up to 12 base pairs from base substitutions. It is proposed that these long range effects are due to base substitutions causing microvariation in the DNA structure to which bleomycin cleavage is sensitive.

Genetically engineered antibody molecules and their application

Immunoglobulin genes can be efficiently expressed following transfection into myeloma cells. Using protoplast fusion, transfection frequencies greater than 10(-3) can be achieved. Compatible plasmids containing two different selectible markers are used to simultaneously deliver heavy and light chain genes to the same cell. To produce molecules with differing specificities the rearranged and expressed variable regions can be cloned from the appropriate hybridoma. In some cases, variable regions from cDNAs can be inserted into the expression vectors. It is possible to manipulate the immunoglobulin genes and produce novel antibody molecules. Antibodies have been produced in which the variable regions from mouse antibodies have been joined to human constant regions. In addition, antibodies with altered constant regions have been produced. These genetically engineered antibodies provide a unique set of reagents to study structure-function relationships within the molecule. They also can potentially be used in the diagnosis and therapy of human disease.

Behavior of dentists and child patients during treatment

This study is part of a larger research project which aims to analyze children's dental fear by making a detailed analysis of the behavioral interactions between dentists and anxious child patients. The behavior of 12 high- and 12 low-anxious children was recorded on videotape during two dental visits in which the children were treated by either experienced or inexperienced dentists. Results indicated a relation between the dentist's experience in treating anxious children and the behavior of child patients. In general, children treated by experienced dentists showed more fear-related behaviors. Furthermore, the behavior of the dentist was related to both his experience and the fear level of the child patient. Experienced dentists showed more communicative behaviors than the inexperienced dentists, but all dentists communicated more with high- than with low-anxious children. Experienced dentists worked faster than inexperienced dentists, but treatment of the high-anxious children was not more time-consuming than treatment of the low-anxious children.

The aromatase active site: the C-6 "front" side of the androgen molecule is required for binding

Solubilized microsomes from human placenta were partially purified by anion-exchange chromatography on a quaternary methylamino-silica column. The aromatase-active fractions were then used for measuring optical difference spectra with various androgens, substituted at positions C-1, 2, 6, 11, 16, 17, and 19. Of these, only androgens substituted at the C-6, or frontside of the steroid backbone induce a strong type I spectrum, as well as competitive inhibition with the natural substrate, 4-androstene-3,17-dione. An in-house made affinity support, synthesized by reacting 6 beta-bromo-androstenedione with aminohexyl-Sepharose at pH 10-11 via a SN2-mechanism, was unable to trap the aromatase cytochrome P-450 component of the enzyme. A 3-dimensional model of the active site accounting for these interactions is proposed.

Inhibition of cytochrome P-450-linked monooxygenase systems by naphthoquinones

Several naphthoquinones, except 2-hydroxy-1,4-naphthoquinone, were found to inhibit microsomal cytochrome P-450-linked monooxygenase activities in rabbit liver and human placenta. In particular, 5-hydroxy-1,4-naphthoquinone inhibited placental estrogen biosynthesis more effectively than it did hepatic drug oxidation reactions. There was little contribution by superoxide radicals to these enzyme inhibitions by naphthoquinones. Spectrophotometric studies revealed that naphthoquinones bind to the cytochrome P-450 component of the monooxygenase complex in both microsomal systems, suggesting that the inhibition is caused by direct interaction of these compounds with the heme.

Computed tomography and ultrasound diagnosis of mycotic aneurysm of the abdominal aorta due to Salmonella

The case of a 56 year old diabetic Chinese male, with a Salmonella bovismorbificans (serogroup C) mycotic aneurysm of the abdominal aorta is presented. The lesion was seen by computed tomography and ultrasound and the patient was successfully treated by primary resection, debridement and grafting. Computed tomography criteria for the diagnosis of mycotic aneurysms of the abdominal aorta are discussed. Ultrasound identified the aortic aneurysm correctly but was unable to demonstrate the associated psoas abscess in this case.

U wave inversion in unstable angina due to left main coronary artery stenosis

A 50-year-old male was admitted to hospital for repeated episodes of chest pain due to unstable angina. Serial electrocardiograms were all normal except for one electrocardiogram, recorded during chest pain, which showed isolated U wave inversion in leads I, V4 and V5. Subsequently, selective coronary arteriography showed isolated 99% stenosis of his left main coronary artery.

In vitro susceptibility of the Bacteroides fragilis group in community hospitals

The antimicrobial susceptibility of clinical isolates of the Bacteroides fragilis group was determined at six community hospitals (one large, greater than 600 beds; and five smaller, 96-325 beds). Imipenem was the most active beta-lactam with 100% of isolates being sensitive at 4 micrograms/ml. The percentage of isolates inhibited at 16 micrograms/ml (and 32 micrograms/ml) for the 7-alpha-methoxy antibiotics was: cefoxitin 66 (90); moxalactam 73 (85); cefotetan 68 (72); cefmetazole 40 (61). Metronidazole, chloramphenicol, and clindamycin were active against 100%, 100%, and 89% at breakpoints of 8 micrograms/ml, 8 micrograms/ml, and 4 micrograms/ml, respectively. The activity of several beta-lactams in our report differed slightly from that reported from university teaching hospitals. There were differences at many of the breakpoints for activity of some of the beta-lactam antibiotics for isolates from the large community hospital as compared with the combined isolates from the smaller community hospitals. Interestingly, the pattern was one of more resistance at the smaller community hospitals.

Normal-phase high-performance liquid chromatographic separations of positional isomers of substituted benzoic acids with amine and beta-cyclodextrin bonded-phase columns

The separation of positional isomers of several substituted benzoic acids was studied using two different columns, i.e. amine and beta-cyclodextrin bonded silicas, at appropriate normal-phase conditions. Although some other columns do separate substituted benzoic acids, particularly the octadecylsilica column in a reversed-phase mode, the present separation under simple normal-phase, isocratic conditions is unique. In particular, the retention order of these acids for the amino bonded-phase column can be roughly predicted using the pKa values of the analytes. On the other hand, due to the strong interaction between substituted benzoic acids and the beta-cyclodextrin bonded phase, a small amount of acetic acid has to be added into the mobile phase to overcome band broadening and tailing problems. Possible retention mechanisms are also discussed.

Stereochemistry of estrogen biosynthesis by a reconstituted aromatase cytochrome P-450 preparation from human placenta

According to the literature, the multistep reaction mechanism of estrogen biosynthesis proceeds with stereospecific loss of the equatorial 1 beta-, and axial 2 beta-protons. These results were deduced from experiments carried out, either with crude microsomes, or at best with impure enzyme extracts. However, when [1,2- 3H]4-androstene-3,17-dione of known absolute 3H-label distribution was incubated with a reconstituted enzyme system, consisting of homogeneous NADPH-cytochrome P-450 reductase and highly purified aromatase, we obtained results that can only be logically explained by a trans- and antiparallel elimination reaction of both the axially oriented C-2 beta-, and C-1-alpha protons. We further demonstrate that the reconstituted enzyme has an aromatase activity optimum at pH 7.2, and an apparent Km of 0.66 microM for NADPH and of 0.24 microM for 4-androstene-3,17-dione. Also, the enzyme requires 3 nmoles of NADPH for each nmole of estrogen that is formed.

Purification and reconstitution properties of human placental aromatase. A cytochrome P-450-type monooxygenase

The hemoprotein component of human placental aromatase (estrogen synthetase) has been purified to a high degree of homogeneity by a combination of affinity and adsorption chromatography on aminohexyl-Sepharose, concanavalin-A-Sepharose, and hydroxyapatite. The monomeric form of the enzyme has an Mr of 55000 +/- 1000 as estimated by sodium dodecyl sulfate gel electrophoresis. Its absolute spectrum shows a high-spin Soret band at 394 nm while its reduced, CO-difference spectrum has a maximum at 447 +/- 1 nm. Full reconstitution of aromatase activity was obtained when it was recombined with a homogeneous preparation of the higher-Mr form of either human placental, or bovine hepatic NADPH-cytochrome P-450 reductase. Critical factors for purification of the very unstable, membrane-bound hemoprotein with good retention of activity were, besides the chromatographic sequence, the use of the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (Chaps) during the solubilization, and the stabilizing effect of the aromatase substrate, 4-androstene-3,17-dione, throughout the procedure. In the presence of NADPH, the reconstituted enzyme system smoothly aromatizes 19-oxoandrostenedione, 19-hydroxyandrostenedione and androstenedione in this order of reactivity. The same reconstituted system also aromatized testosterone, but it was inactive towards 19-norandrostenedione. Known cytochrome P-450 inhibitors decreased its activity. We conclude: (a) the terminal oxidase of human placental aromatase is indeed a cytochrome P-450-type monooxygenase; (b) the multistep aromatization reaction of C19 androstenes is catalyzed by a single enzyme; (c) aromatization of 19-norsteroids reported by other authors must be due to a different aromatase. Experimental data obtained with the reconstituted enzyme are fully compatible with the concept of a reaction mechanism for the aromatization sequence involving an all-trans, antiparallel elimination of the 19-methyl group, the 2 beta proton and the 1 alpha proton, rather than the 1 beta proton, as generally assumed.

Treatment of irresectible hepatocellular carcinoma with intrahepatic arterial lipoidal mixed with adriamycin and mitomycin C

Four patients with advanced hepatocellular carcinoma, but with stage I functional disease, were treated with intrahepatic arterial lipoidal mixed with small doses of Adriamycin (20 mg) and Mitomycin C (10 mg). Regression was seen in 3 out of the 4 patients. In 2 patients, there was substantial regression of tumour clinically, radiologically and biochemically. The treatment was tolerable without marrow depression or deterioration of liver function. Mild fever (37 degrees C) was seen in 2 and epigastric pain in 1. This form of treatment opens up scope for further improvement in the management of irresectable hepatocellular carcinoma.

Ultrasonography in the diagnosis of cholestatic jaundice

Fifty consecutive patients (32 males and 18 females) with cholestatic jaundice were examined by grey-scale ultrasound from June 1981 to June 1983. All patients were studied without access to case notes. All patients had a diagnosis established by subsequent liver biopsy, clinical course, surgery or autopsy. Using the presence or absence of a dilated biliary system as the criterion, intrahepatic or extrahepatic cholestasis was correctly differentiated in 48 of the 50 patients, giving an overall accuracy of 96%. All 16 patients with intrahepatic cholestasis were correctly identified. Two of the 34 patients with extrahepatic cholestasis, each of whom had biliary stones, were misdiagnosed as intrahepatic cholestasis. In the 34 patients with extra-hepatic cholestasis, site of obstruction was defined in 55.9%, and specific aetiology diagnosed in 44.1%. Ultrasound proves to be an accurate method for the evaluation of cholestatic jaundice, and would have a definite value as a screening test before proceeding to invasive studies.

Physiologic changes induced by endotracheal instillation and suctioning in critically ill preterm infants with and without sedation

Endotracheal instillation and subsequent suctioning produces fluctuations of intracranial pressure (ICP), mean arterial pressure (MAP), and cerebral perfusion pressure (CPP) in sick preterm infants. In an attempt to observe if these fluctuations could be minimized using sedation, we studied a group of seven sick mechanically ventilated preterm infants with and without sedation. Continuous monitoring of ICP, MAP, heart rate, CPP, and arterial oxygen tension (PaO2) were obtained. The statistical analysis of the data revealed significant blunting of fluctuations of MAP, ICP, and CPP with sedation.

Purification and properties of human placental NADPH-cytochrome P-450 reductase

Human placental NADPH-cytochrome P-450 reductase (EC 1.6.2.4) was purified to electrophoretic homogeneity in two chromatographic steps with a high retention of bioactivity. After solubilization with 1% sodium cholate in a protective medium containing 20% glycerol, 10 microM 4-androstene-3,17-dione, 1 mM dithiothreitol, and 0.2 mM EDTA, a 35-60% ammonium sulfate precipitate was prepared. The crude protein mixture was then applied to a 2',5'-ADP-Sepharose 4B affinity column, followed by high-performance anion-exchange chromatography (Pharmacia Mono-Q column). Two forms of the reductase were isolated. One was eluted at higher salt concentration and had a relative mass (Mr) of 79 kdaltons (kDa) as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and high-performance gel permeation chromatography. A smaller size reductase with a Mr of 70 kDa, eluting at lower salt concentration, was also formed by trypsinolysis of the 79-kDa reductase. It must therefore be regarded as a proteolytic artifact. The absolute spectra in the visible region of the two reductases were identical with maxima at 376 and 452 nm, typical of a flavoprotein. They also had the same specific activity of 24.7 +/- 0.7 mumol/min per milligram protein towards cytochrome c. However, only the 79-kDa reductase showed aromatase-reconstitution activity. The homogeneity of these reductases was further confirmed by the appearance of a single peak when subjected to gradient, reversed-phase high-performance liquid chromatography. According to its amino acid composition, the 79-kDa reductase is a highly acidic and hydrophobic protein, composed of 695 residues.

An evaluation of total parenteral nutrition using Vamin and Aminosyn as protein base in critically ill preterm infants

A total of 75 preterm infants with gestation less than 32 wk received total parenteral nutrition (TPN) using Vamin and Aminosyn as protein base lasting more than 20 days. They were monitored for signs of liver dysfunction, cholestatic jaundice, and TPN-induced metabolic bone disease (osteopenia of prematurity). It was observed that severity of TPN-induced cholestasis depends on the duration of TPN and quantity of protein infused. When used as a protein base, Vamin seemed to be superior to Aminosyn. TPN-induced metabolic bone disease was strongly correlated to the duration of TPN. We suggest close monitoring of critically ill preterm infants on TPN for quantity of protein infusate, liver dysfunction, cholestatic jaundice, and TPN-induced metabolic bone disease. Intravenous protein intake should be limited to less than 2.5 g/kg/day in preterm infants with gestation less than 32 wk.

Purification of oestrogen synthetase by high-performance liquid chromatography. Two membrane-bound enzymes from the human placenta

Human placental NADPH-cytochrome P-450 reductase, obtained by 2',5'-ADP-Sepharose affinity chromatography, was separated into two reductase-active peaks on a Pharmacia Mono-Q column. By this short, two-step chromatographic procedure, the two reductases were obtained in a homogeneous state with high retention of activity and in over 900-fold purification. Aromatase-reconstituting activity was present only in the higher-molecular-weight reductase (79 000 D), not in the smaller, 70 000 D reductase, which turned out to be a proteolysis product of the former. Both proteins were eluted as a single peak in reversed-phase high-performance liquid chromatography on a Protesil-diphenyl column. Similar results were obtained with bovine hepatic NADPH-cytochrome P-450 reductases. On the other hand, starting from a reductase-free preparation, we have obtained by high-performance ion-exchange chromatography and high-performance size-exclusion chromatography, only partial purification of the aromatase cytochrome P-450, which showed the following values: aromatase activity, 3.995 nmol/min/mg protein (60-fold purification); cytochrome P-450 content, 1.376 nmol/mg protein (23-fold purification); molecular weight, 165 000 D (estimated as an aggregate by size-exclusion chromatography). Although complete purification of the aromatase component has yet to be accomplished, our results suggest that high-performance ion-exchange chromatography on a Mono-Q column is very useful for the purification of acidic, membrane-bound enzymes with good retention of activity.

Inactivation of human placental aromatase by 6 alpha- and 6 beta-hydroperoxyandrostenedione

The epimeric 6 alpha- and 6 beta-hydroperoxy derivatives of androstendione caused irreversible inactivation of human placental aromatase. Microsomes from term-placentae were first preincubated in the presence of increasing concentrations of the hydroperoxides. The microsomes were then washed free of steroids and its residual aromatase activity was assayed by the tritium-exchange method to [3H]water. Aromatase activity decreased in a time-, and concentration-dependent manner; the axial, beta-hydroperoxy epimer was the slightly stronger inactivator. Less inactivation occurred when during the preincubation stage the natural aromatase substrate, androstenedione, or the anti-oxidant, dithiothreitol, was added. The sulfhydryl reagent, p-hydroxy-mercuribenzoate, decreased this protective effect. The inactivation is not dependent on the presence of NADPH. Both steroids induced a Type I difference spectrum with a Ks of 0.167 microM and 0.163 microM for the 6 alpha-, and the 6 beta-hydroperoxyandrostenedione, respectively. We suggest that these 6-hydroperoxyandrogens may function as active-site directed inhibitors and inactivators of estrogen synthetase through oxidation of cysteine residues.

Two-dimensional echocardiographic abnormalities of right atrial metastatic tumors in hepatoma

We describe two patients suffering from hepatoma who presented with right atrial metastatic tumors as a result of invasion of the inferior vena cava and extension into the right atrium. Two-dimensional echocardiographic studies detected the right atrial tumor during life in both patients and the invasion of the inferior vena cava in one patient.

CSF shunt complications: an analysis of contributory factors

The complications arising from 195 shunting procedures are described and correlated with patient and operative variables. Neither the patient's age, sex, type of hydrocephalus, length of surgery, nor the use of prophylactic antibiotics correlated significantly with subsequent shunt complications. However, the surgeon performing the procedure and the type of shunt used were highly significant correlates.

Quantification of mitral valvular incompetence

The hemodynamic and angiographic data of 147 individuals were analyzed in an attempt to assess the value of three techniques used in the diagnosis of mitral incompetence. One hundred patients had clinical evidence of mitral incompetence (group A) and 47 had normal hemodynamics (group B). The degree of mitral incompetence was assessed in all 147 individuals by two methods: determination of a regurgitant index (RI) using indicator dilution curves and determination of a regurgitant fraction (RF) using left ventricular volumes. In 26 patients of group A and 26 individuals in group B mitral incompetence was also assessed by cineangiocardiography. Each of these methods was compared with the clinical and hemodynamic evidence of mitral valvular incompetence. Both the determination of RI by dye dilution curves and RF by angiocardiography were found to be useful in separating normal individuals from patients with mitral valvular incompetence. Severe mitral incompetence is associated with an RI greater than 35% and with an RF greater than 55%. The degree of incompetence by either method was not well correlated with any independent hemodynamic variable. The use of cine angiocardiography to quantify the degree of mitral incompetence was found to be too subjective, depending on the observer, and thus less useful.

Two-dimensional and pulsed Doppler echocardiographic abnormalities in coronary artery-pulmonary artery fistula

We describe two patients who presented with precordial continuous murmurs which were diagnosed clinically as due to patent ductus arteriosus; however, two-dimensional echocardiographic and pulsed Doppler echocardiographic studies showed dilatation of the left main coronary artery with turbulent flow during systole in the lumen in both patients. Subsequent selective coronary angiographic studies showed bilateral coronary artery-pulmonary artery fistula in one patient and left coronary artery-pulmonary artery fistula in the other. This study illustrates that in a patient presenting with a continuous murmur which is suggestive of patent ductus arteriosus, such two-dimensional and pulsed Doppler echocardiographic findings as were seen in our patients should immediately alert the physician that he may be dealing with a case of coronary arterial fistula.

Serum levels of C-reactive protein in neonatal respiratory distress syndrome

Serum levels of C-reactive protein (CRP) were measured within 96 hours of birth in 55 neonates with respiratory distress syndrome (RDS), 19 neonates with no significant medical illness other than an unstable cardiovascular state, and 13 neonates with a variety of pulmonary and extra-pulmonary problems either alone or in combination with RDS. The median serum CRP level in patients with RDS (2 micrograms/ml) was neither elevated nor different from CRP levels in infants with unstable cardiovascular systems (median CRP level, 2 micrograms/ml); however, neonates with other problems including pneumonia, aspiration, and extrapulmonary sepsis had significantly elevated serum CRP values (median 24 micrograms/ml). CRP levels are not elevated in neonatal RDS. Measurement of this acute phase reactant provides a rapid and reliable means of helping to distinguish infants with uncomplicated RDS from those with other serious pulmonary and extrapulmonary disease.