Orthotopic cardiac transplantation for the failing Fontan circulation

OBJECTIVE

Modified Fontan procedures are now employed in several conditions unsuitable for bi-ventricular repair. Selection criteria have been relaxed. The procedure is palliative. Longterm outlook is unknown. This study evaluated factors associated with the development of a failing Fontan circulation and transplantation results.

METHODS

Retrospective review of patients referred to a single centre for cardiac transplant assessment.

RESULTS

Between 1985 and 1996, 46 of 448 cardiac transplants were performed for congenital heart disease. Nine of these were performed in patients with a failing Fontan circulation (four adults, five children). In six cases, the dominant ventricle had left ventricular (LV) morphology. Congenital anomalies included double outlet right ventricle (three cases), double inlet left ventricle (two cases), tricuspid atresia (two cases), and pulmonary atresia with intact ventricular septum (one case). Fontan procedures were performed in absence of sinus rhythm (four cases), atrio-ventricular (AV) valve regurgitation (two cases), aortic regurgitation and systolic LV dysfunction (one case), elevated mean pulmonary artery pressure (one case), and older age (>7 years, eight cases). Three patients required early re-operation and two needed permanent pacing. Subsequent deterioration associated with loss of sinus rhythm (four cases) and progressive AV valve regurgitation (seven cases) led to transplant assessment (at < 1 year, five cases; at 2-12 years, four cases). All patients were listed for transplantation. Three patients required intravenous inotropic support and three patients with lymphocytotoxic antibodies needed prospective crossmatching. Donor cardiectomy was modified to facilitate implantation. The recipient operation involved pulmonary artery reconstruction (using pericardium), modified atrial and direct caval anastomoses. Three patients died within 24 h of surgery (two graft failures, one haemorrhage). In operative survivors (n = 6), intensive care stay was 3-16 days, and hospital stay ranged from 14 to 32 days. There have been no subsequent deaths (follow up, 0.5-4.7 years).

CONCLUSION

In high-risk Fontan candidates, transplantation may be preferable at the outset. Previous surgery, lymphocytotoxic antibodies, indeterminate pulmonary vascular resistance, emergency status, sub-optimal donor selection, and perioperative bleeding contribute to peri-operative mortality. In survivors, the outcome remains very encouraging.

Effect of immunosuppression after cardiac transplantation in early childhood on antibody response to polysaccharide antigen

BACKGROUND

Three children who had cardiac transplantation before age 4 years later presented with recurrent sinopulmonary infection caused by organisms including Streptococcus pneumoniae, in which capsular polysaccharide plays an important part, one developed bronchiectasis. We therefore studied responses to polysaccharide antigen after immunosuppression started in early childhood.

METHODS

Antibodies against pneumococcal and haemophilus polysaccharides, and total IgG, IgG1, IgG2, and IgA concentrations were measured in 33 cardiac-transplant recipients transplanted before the age 4 years (group 1) and after that age (group 2). Patients with low pneumococcal and haemophilus antibody concentrations were immunised with 23 polyvalent pneumococcal and tetanus-haemophilus conjugate vaccines and antibody responses were measured.

FINDINGS

Five patients from group 1 and seven from group 2 were transplanted for congenital heart disease and ten patients in each group had heart transplants because of cardiomyopathy; none were asplenic. Group 1 (16 patients) were aged 2-10 years when investigated, group 2 (17 patients), were 6-16 years. Four of 16 patients in group 1 responded to pneumococcal polysaccharide vaccine compared with 14 of 17 in group 2 (p=0.0016). This difference remained when those in group 1, aged less than 4 years at investigation, were excluded (p=0.0060). Response to haemophilus-conjugate vaccine was similar in both groups (14 of 16 vs 14 of 17, p=1.0). Significantly more patients who failed to respond to pneumococcal vaccine had low IgG2 concentrations (p=0.0269).

INTERPRETATION

Children who had a transplantation and immunosuppression in early childhood before they had developed antibody responses to pneumococcal polysaccharide, still failed to show a response when older-ie, when such responses are the norm. Ongoing immunosuppression prevents the maturation of antipolysaccharide responses leaving children susceptible to severe and recurrent damaging infection.

Thiamine deficiency mimicking acute rejection following cardiac transplantation

We describe a recipient of an orthotopic cardiac transplant who developed severe ventricular dysfunction following an episode of sepsis. He had normal cardiac biopsies and responded to treatment with thiamine. Causes other than rejection should be considered in patients who have received a cardiac transplant and who present in cardiac failure.

Studies on base-boronated oligonucleotides. 2 (1). Incompatibility of DMT and cyanoborane groups during oligonucleotide synthesis

The cyanoborane (-BH2CN) nucleosides and nucleotides are a new class of compounds that mimic natural and synthetic congeners in many ways and exhibit interesting biochemical and biophysical properties. The B-N bond is isoelectronic with the C-N+ bond of N7-alkylated 2'-nucleosides, as well as the C-C bond of naturally occurring 7-alkyl-7-deazanucleosides. These compounds differ from normal guanosine in that they are incapable of hydrogen bonding at the 7-position. The syntheses of N7-cyanoborane 2'-deoxyguanosine, N2-(dimethylaminomethylene)-N7-cyanoborane 5'-(dimethoxytrityl)-2'-deoxyguanosine (3), and N2-isobutyryl-N7-cyanoborane 5'-(dimethoxytrityl)-2'-deoxyguanosine (9) are described. Removal of the dimethoxytrityl (DMT) group from 3 or 9 is accompanied by significant loss of the cyanoborane moiety. Additionally, dimethoxytritylation of a cyanoboronated nucleoside leads to partial deboronation, thus limiting use of the commercially available 5'-DMT nucleosides as viable precursors in base-boronated oligonucleotide synthesis. The incompatibility of the cyanoborane moiety under DMT removal/addition conditions necessitated the search for an alternative method of protecting the 5'-hydroxyl of the nucleoside. This paper addresses the possible cause of deboronation and describes the synthesis of N7-cyanoboronated nucleosides by a method that avoids transient protection of the sugar hydroxyls.

Differential pulmonary flow after heart transplantation in patients with malposition of the great arteries

In transposition of the great arteries the right lung is preferentially perfused, and this may be due to the orientation of the right pulmonary artery when the main pulmonary artery comes off in a posterior position. In this study the mean perfusion of the right lung was 61% in six patients who had "correction" of the great artery malposition at the time of heart transplantation. This suggests that anatomic correction of pulmonary artery orientation does not correct the preferential perfusion to the right lung.

Dermal fibroblasts from venous ulcers are unresponsive to the action of transforming growth factor-beta 1

Failure to reepithelialize is the major clinical problem in venous ulcers. It is not clear whether the problem resides with keratinocytes or with inadequate and improper formation of extracellular matrix. In this study, we characterized the biosynthetic activity and response to transforming growth factor-beta 1 (TGF-beta) of dermal fibroblast cultures isolated from biopsies of venous ulcers and from normal thigh skin (controls) of seven patients. We found that baseline 3H-proline incorporation was similar in fibroblasts from venous ulcers and control skin (p= 0.1716). No difference was detected by ELISA between ulcer and control fibroblasts in the synthesis of total TGF-beta (p = 0.2309), and the mRNA levels for alpha 1(I) procollagen and TGF-beta were comparable in both groups. However, TGF-beta (0.1-5 ng/ml) enhanced collagen protein synthesis by more than 60% and in a dose-dependent manner (r = 0.997) in control fibroblast cultures, while failing to stimulate collagen production by venous ulcer fibroblasts (p = 0.0001). This unresponsiveness to TGF-beta was associated with up to a fourfold decrease in TGF-beta Type II receptors. We conclude that fibroblasts from the edge of non-healing venous ulcers are unresponsive to the action of TGF-beta, and that this blunted response may cause faulty deposition of the extracellular matrix needed for reepithelialization and wound healing.

The effects of Escherichia coli sepsis and short-term ischemia on coronary vascular reactivity and myocardial function

Ischemia and reperfusion stun the myocardium and the coronary vasculature. We have previously shown that a short period (15 min) of global ischemia in the isolated rat heart causes impaired coronary constriction in response to a thromboxane analog U46619 during reperfusion. Sepsis has also been shown to affect myocardial and vascular function. In the present study, we determined whether Escherichia coli-induced sepsis would exacerbate the effects of ischemia on the coronary circulation. Sepsis prolonged the impairment in the coronary constriction response to U46619 following short term ischemia. We hypothesized that sepsis-induced increases in nitric oxide (NO) production caused the delay in the recovery of the contractile response to U46619. Perfusion with NO synthase inhibitors however indicated that the impaired response was not due to NO. However, NO did appear to have a significant role in the development of myocardial ischemic contracture and on the recovery of diastolic function after ischemia. Inhibitors of NO synthase also caused a significant increase in basal coronary perfusion pressure as well as in the maximum coronary pressure generated in response to U46619, suggesting a role of NO in regulating basal coronary vascular resistance in the isolated rat heart. Some of these effects were more pronounced in septic rat hearts than in the sham surgical rat hearts, consistent with altered nitric oxide production in the septic rat hearts.

Durometer measurements of skin induration in venous disease

BACKGROUND

The degree of skin induration (lipodermatosclerosis) around venous ulcers has prognostic significance; however, objective measurements are needed to assess the induration. The durometer, an engineering instrument used to measure the hardness of metals and plastic, has recently been adapted to assess skin induration.

OBJECTIVE

The purpose of this study was to measure skin induration and its relationship to skin ulceration by the use of a durometer, and to determine the influence of edema, if any, on durometer measurements.

METHODS

The degree of skin induration on the medial leg was determined in six sequential, nonselected patients with lipodermatosclerosis and leg ulcers, and in five normal volunteers by using a blinded observer's clinical score (0 = normal to 3 = maximal induration) and a hand-held Type 0 durometer. In addition, durometer readings in 14 patients with edema and eight control subjects were taken on the tibia, the dorsum of the foot, and behind the ankle.

RESULTS

Durometer readings in patients with leg ulcers and lipodermatosclerosis diminished as one measured from the superior edge of the ulcer to the knee (r = 0.925). The higher the clinical skin score the higher were the durometer readings (P = 0.0062). The presence of edema did not influence durometer measurements.

CONCLUSION

The durometer is an effective and reliable instrument for measuring the degree of skin induration in venous ulceration and its readings are not affected by edema. Ulcers occur in skin most affected by lipodermatosclerosis.

TGF-beta3 stimulates and regulates collagen synthesis through TGF-beta1-dependent and independent mechanisms

In contrast to the TGF-beta1 and beta2 isoforms, TGF-beta3 has shown the ability to downregulate scarring and fibrosis in vivo under certain experimental conditions. In this study, we determined the direct effects of TGF-beta3 on cultures of human dermal fibroblasts. TGF-beta3 (0.1 to 100 pg per ml) increased DNA synthesis up to 50% (p < 0.01, r = 0.970), collagen protein synthesis up to 200% (dose range of 0.1 to 5 ng per ml, p < 0.001, r = 0.990), and increased alpha1(I) procollagen mRNA levels (r = 0.999), with maximal effects (200% of control) observed by 24 h. Collagen lattice contraction was increased by more than 50% in response to TGF-beta3 (p < 0.001), and to a similar extent as the TGF-beta1 isoform. Stimulation of collagen synthesis and of alpha1(I) procollagen mRNA levels in response to TGF-beta3 was partially blocked by a TGF-beta1-specific anti-sense oligonucleotide but was still detectable (35% greater than baseline) when TGF-beta3 was added to dermal fibroblasts from TGF-beta1 knock-out mice. In contrast with these stimulatory effects, however, downregulation of alpha1(I) procollagen, alpha1(III) procollagen, and TGF-beta1 mRNA levels toward baseline occurred when TGF-beta3 (0.1 to 5 ng per ml) was added simultaneously and in combination with TGF-beta1. We conclude that stimulation of collagen synthesis by TGF-beta3 occurs through TGF-beta1-dependent and independent pathways. By downregulating the response to TGF-beta1 and by shifting from one pathway to the other, TGF-beta3 can dampen and provide fine-tuning to the overall TGF-beta's induced program of collagen deposition.

The use of 99Tcm-DTPA aerosol and caesium iodide mini-scintillation detectors in the assessment of lung injury during cardiopulmonary bypass surgery

Lung injury is a well-documented adverse effect of cardiopulmonary bypass. The mechanism of injury is not fully understood, but pulmonary hypoxia may be a factor. Post-operative pulmonary epithelial permeability (PEP) in ventilated versus non-ventilated lungs was measured within 2 h of return to the intensive care unit using a 99Tcm-diethylenetriamine pentaacetate aerosol technique. A portable scintillation detector system was required. Sodium iodide detectors have been used previously with this technique but are cumbersome. This study used mini caesium iodide detectors (Oakfield Instruments, Oxon, UK), which can be attached directly to the patient and are more suited to the intensive care setting. The clearance half-time from lung to blood (T1/2LB) was measured in 31 patients (62 lungs). The mean (+/- S.E.M.) clearance half-times were 42.3 +/- 2.7 and 45.7 +/- 3.8 min for non-ventilated and ventilated lungs respectively, with a mean difference of 3.4 +/- 3.1 min (P > 0.05). We conclude that, using this technique, no significant difference in PEP is observed between ventilated and non-ventilated lungs in patients undergoing cardiopulmonary bypass.

Two flavonol triglycosides from flowers of Indigofera hebepetala

Two new flavonol triglycosides, kaempferol 3-omicron-alpha-L-rhamnopyranosyl(1->2)-beta-D-galactopyranoside-7-O- alpha-L-arabinofuranoside and kaempferol 3-O-alpha-rhamnopyranosyl(1-->6)-beta-D-galactopyranoside-7-O- alpha-L-arabinofuranoside were isolated from the flowers of Indigofera hepepetala, together with three known glycosides, kaempferol 3-omicron-alpha-L-arabinopyranoside-7-O-alpha-L-rhamnopyranoside, kaempferol 3-O-alpha-L-rhamnopyranoside-7-O-alpha-L-arabinopyranoside and kaempferol 7-rhamnoside. The structures were determined by means of Rf values, UV, EI-mass spectrometry, FAB-mass spectrometry, 1H NMR, 13C (B.B and DEPT) NMR, NOE difference measurement and 1H-1H COSY spectral data.

Acute lipodermatosclerosis is associated with venous insufficiency

BACKGROUND

Acute lipodermatosclerosis is characterized by pain and tenderness in the medial aspect of the leg. It is thought to be the result of venous insufficiency and to be the acute counterpart of chronic lipodermatosclerosis, a hallmark of venous disease. However, there is no direct evidence linking acute lipodermatosclerosis to venous disease.

OBJECTIVE

Our purpose was to determine whether acute lipodermatosclerosis is associated with venous insufficiency.

METHODS

With air plethysmography, we determined the venous filling index, the ejection fraction, and the residual volume fraction in 15 sequential patients with acute lipodermatosclerosis.

RESULTS

Ten of the 15 patients (67%) had at least one abnormal result, eight (53%) had two, and two (13%) had three. In four patients (27%), abnormalities of both reflux and ejection were noted. Duplex venous ultrasonography, in two of the patients with normal results from air plethysmography, showed incompetent perforators at sites of lipodermatosclerosis.

CONCLUSION

Acute lipodermatosclerosis is associated with objective findings of venous insufficiency in a high percentage of patients. It is likely that this condition is the result of venous disease.

Video-assisted thoracoscopy in the evaluation of penetrating thoracic trauma

The management of patients who present with penetrating thoracic trauma but are haemodynamically stable may be subjective and imprecise. We report our initial experience with the use of video-assisted thoracoscopy in a series of five patients in whom accurate assessment was achieved and unnecessary thoracotomy avoided.

Topically applied recombinant tissue plasminogen activator for the treatment of venous ulcers. Preliminary report

BACKGROUND

Increasing evidence suggests that fibrin deposition is an important pathogenic component of venous ulceration and that fibrin removal could accelerate ulcer healing.

OBJECTIVE

We sought to determine whether topical application of recombinant tissue plasminogen activator (tPA) compounded in 1% hyaluronate acid (HA) can be used safely in venous ulcers and whether it can accelerate healing.

METHODS

Twelve patients were randomized in a double-blind fashion in three sequential groups of four subjects each, so as to receive daily topical application of either placebo (HA alone, one patient) or tPA/HA (three patients) at escalating doses of 0.25, 0.5, and 1.0 mg/ml of tPA for 4 weeks.

RESULTS

No safety problems occurred, and we found a close direct correlation between mean ulcer reepithelialization, fibrin removal, and the dose of topically applied tPA (r = 0.991).

CONCLUSION

In this first study to examine its usefulness, topically applied tPA appears to be a safe and promising agent for treating venous ulcers.

Base-boronated dinucleotides: synthesis and effect of N7-cyanoborane substitution on the base protons

Boron-modified nucleic acids comprise a new set of DNA mimics that have potential biological and therapeutic applications. A series of nine dinucleotides containing N7-cyanoborane-2'-deoxyguanosine ((7b)dG) at the 3', 5' or both positions of the phosphodiester linkage have been synthesized using solution phase phosphoramidite chemistry. Fmoc was used as the 5'-protecting group because of incompatibility of the cyanoborane moiety with 5'-DMT cations generated during the deprotection step. The presence of the cyanoborane group was confirmed on the basis of Fab-MS and 1H NMR spectroscopy. The H-8 proton of (7b)dG in the dinucleotides shifted 0.35-0.80 p.p.m. downfield relative to that of unmodified dG. A comparison of the D20 exchange kinetics of the H-8 proton at 60 degrees C showed that H-8 of (7b)dG is very labile relative to unmodified dG, indicating that the N7-cyanoborane modification increases the acidity of the H-8 proton of (7b)dG. These studies illustrate the feasibility of synthesizing boron-containing oligonucleotides which are modified at the N7-guanine to block Hoogsteen pairing in the DNA major groove.

Serum levels of immunoglobulins in thermal burns

Thermal injury is known to induce alterations in the immune system. Sixty-four patients of thermal burns have been studied for serum immunoglobulins. Concentrations of IgG, IgA and IgM were decreased immediately after injury and gradually increased up to normal limits on the 30th postburn day.

Recognition of B-cell epitopes of the 65 kDa HSP in Behçet's disease

B-cell epitopes of the mycobacterial 65 kDa heat shock protein (HSP) were mapped in sera from patients with Behçet's Disease (BD). A series of 47 overlapping synthetic peptides (15ers) derived from the sequence of the Mycobacterium tuberculosis 65 kDa HSP was used in ELISA. Significant increases in IgA and IgG antibody levels were observed with peptides 111-125, 154-172 and 311-326 in sera from BD, compared with those from controls. Homologous peptides derived from the sequence of the human mitochondrial 60 kDa HSP were then examined. Peptides 136-150 and 336-351 showed comparable results to the homologous mycobacterial peptides 111-125 and 311-326, respectively. The B-cell epitopes defined in this investigation overlap with the T-cell epitopes the authors have previously reported in BD. Inhibition studies are consistent with the view that antibodies to each of the three B-cell epitope peptides represent a small proportion of the total B-cell epitope repertoire elicited by the 65 or 60 kD HSP. Sequential antibody studies suggest that IgA and IgG antibody titres to one or all three peptides tested may increase during exacerbation of ocular disease. The functional role of these antibodies needs to be determined, but the peptides may be involved in the immunopathogenesis of BD as they can induce experimental uveitis in Lewis rats, which is a principal manifestation of BD.

Vascular complications of lung transplantation

BACKGROUND

The data on vascular anastomotic complications after single-lung and bilateral lung transplantation are scant.

METHODS

We reviewed the data on our patients having single and bilateral lung transplantation to examine our experience and management of vascular anastomotic complications.

RESULTS

We retrospectively identified 5 of 109 consecutive patients undergoing lung transplantation who had postoperative pulmonary arterial or venous obstruction. There were 4 women and 1 man (age range, 32 to 53 years). Three patients had left single-lung transplantation, 1 patient had right single-lung transplantation, and 1 patient underwent bilateral sequential lung transplantation. Complications comprised two right-sided and two left-sided pulmonary artery stenoses and one combined left pulmonary arterial and venous obstruction. Isotope perfusion scanning was used in 3 patients and suggested a vascular stenosis in all of them. Pulmonary angiography was used in each as a confirmatory test and to demonstrate anatomic details. Transesophageal echocardiography was used in 1 patient and did not detect a right pulmonary artery stenosis. One patient underwent revision of a pulmonary artery stenosis with a period of warm ischemia and subsequent fatal lung injury. Two revisions were undertaken on cardiopulmonary bypass with a cold blood flush to the transplanted lung. One venous anastomotic angioplasty with stent insertion was performed. Two patients died before treatment. All 5 patients died between 5 and 630 days postoperatively.

CONCLUSIONS

Vascular complications carry a high mortality. Reoperation, preferably using cardiopulmonary bypass and a cold blood flush technique to avoid further lung injury, is recommended. In high-risk patients, dilation or stent insertion can be considered.

Evaluation of 1-azabicyclo[2.2.2]oct-3-yl alpha-fluoroalkyl-alpha-hydroxy-alpha-phenylacetates as potential ligands for the study of muscarinic receptor density by positron emission tomography

Both 1-azabicyclo[2.2.2]oct-3-yl alpha-(1-fluoroeth-2-yl)-alpha-hydroxy-alpha-phenylacetate (FQNE, 5) and 1-azabicyclo[2.2.2]oct-3-yl alpha-(1-fluoropent-5-yl)-alpha-hydroxy-alpha-phenylacetate (FQNPe, 6) were prepared and evaluated as potential candidates for the determination of muscarinic cholinergic receptor (mAChR) density by positron emission tomography (PET). The results of in vitro binding assays demonstrated that although both 5 and 6 had high binding affinities for m1 and m2 mAChR subtypes, 6 displayed a higher affinity (nM, m1; KD, 0.45, m2; KD, 3.53) as compared to 5 (nM, m1; KD, 12.5, m2; KD, 62.8). It was observed that pretreatment of female Fisher rats with either 5 or 6 prior to the i.v. administration of Z-(-)(-)-[131I]-IQNP, a high-affinity muscarinic ligand, significantly blocked the uptake of radioactivity in the brain and heart measured 3 h postinjection of the radiolabeled ligand. These new fluoro QNB analogues represent important target ligands for evaluation as potential receptor imaging agents in conjunction with PET.

Role of gamma delta T cells in pathogenesis and diagnosis of Behcet's disease

BACKGROUND

Behcet's disease (BD) is a multisystem disorder of unknown pathogenesis. The diagnosis is based on a set of international clinical criteria. Previous investigations have suggested that immunological cross-reactivity between peptides within streptococcal heat-shock proteins and human peptides might be involved in the pathogenesis of BD. We tested four peptides from mycobacterial heat-shock proteins to see if they specifically stimulated gamma delta T cells from BD patients. We then investigated this response to see whether it could be used as a laboratory test to diagnose BD.

METHODS

We used a T-cell proliferative test to assay responses to four mycobacterial 65 kDa heat-shock-protein peptides and to four homologous peptides derived from the sequence of the human 60 kDa heat-shock protein.

FINDINGS

We elicited significant gamma delta T-cell responses to the mycobacterial peptides in 25 (76%) of 33 patients with BD, compared with 2 (3.6%) of 55 controls with recurrent oral ulcers, systemic disease, or no disorders. The proportion of BD patients who had false-negative results decreased if the test was done during clinical manifestation of disease activity. There was a correlation between disease activity and T-cell responses. Four homologous peptides from human 60 kDa heat-shock protein also specifically stimulated T cells from patients with BD but with lower stimulation indices.

INTERPRETATION

Activation of peripheral-blood mononuclear cells with the four heat-shock-protein peptides elicited significant T-cell proliferative responses by the gamma delta subset of T cells, which may regulate alpha beta T cells. Because these peptides have a high specificity for BD, this assay can be used as a laboratory diagnostic test for BD.

Healing of the bronchus in pulmonary transplantation

OBJECTIVE

To review the results of bronchial healing in a consecutive series of 100 isolated pulmonary transplants, performed at one centre between 1987 and 1994.

METHODS

A retrospective review of 123 assessable bronchi (61 in single lung and 62 in bilateral lung) transplants was carried out. All anastomoses were assessed by bronchoscopy at 7-10 days, and follow up was from one to seven years. The effect on bronchial dehiscence or stenosis requiring endobronchial stent, of suture technique, pre and post operative steroid administration, bronchial wrap, donor ischaemic time and time to first rejection episode was assessed.

RESULTS

Complications of airways healing occurred in four patients: stenosis in two and dehiscence in two (1.6% of bronchi at risk in both groups). Airway complication was not affected by steroids, pre-operative diagnosis, presence of a wrap (34 with pericardium or omentum, 89 with peribronchial tissue alone) or any other variable. There was a higher incidence of dehiscence (2/36) with continuous rather then interrupted (0/87) suture, but this was not statistically significant. There was one airway-related death. Two patients who required anastomotic stenting remain alive and well.

CONCLUSIONS

A very low complication rate can be achieved without recourse to bronchial wrapping, telescoping anastomoses or steroid avoidance. Combined heart-lung transplantation or bronchial revascularisation are not required to achieve reliable bronchial healing.

Effects of short term ischemia and reperfusion on coronary vascular reactivity and myocardial function

Ischemia and reperfusion have been shown to cause damage to the endothelium as well as to the cardiac myocyte. Although the vasodilator response has been shown to be impaired following ischemia and reperfusion, the effect of a short period of global ischemia on the contractile response of the coronary vasculature is not clear. In the present study, coronary vasoconstriction in response to U46619, PGF2 alpha, 5-HT, and KCl was found to be depressed for at least 15 min following 15 min of in vitro global ischemia in rats hearts. Vasodilator blockers or inactivators were used in an effort to restore this depressed coronary response. Indomethacin (5 microM) was used to block production of vasodilator prostaglandins, L-NAME (30 microM) to block production of nitric oxide (NO), and adenosine deaminase (2.4 units/ml of coronary flow) to inactivate adenosine. None of these agents restored the normal coronary constrictor response following ischemia. When superoxide dismutase and catalase (both 20 micrograms/ml of coronary flow) were infused for 5 min before and after ischemia, the coronary response recovered more than 100% of its preischemic value by 15 min of reperfusion, but still remained depressed at 5 min reperfusion. These data suggest that free radicals produced during ischemia and/or reperfusion may be at least partly responsible for this temporary "stunning" of the coronary vasculature. Since the impaired contractile response was still present at 5 min reperfusion when the buffer was supplemented with oxygen radical scavengers, another mechanism must also be involved in this "stunning" process.

Flavonoid glycosides and an anthraquinone from Rumex chalepensis

Besides rutin, quercetin 3-rhamnoside and kaempferol 3-rhamnosyl(1-->6) galactoside, a new flavonol glycoside, quercetin 3-glucosyl(1-->4)galactoside, and 1,6,8-trihydroxy-3-methyl anthraquinone (emodin) have been characterized from leaves of Rumex chalepensis. The structures were established on the basis of Rf values, acid hydrolysis to aglycone and sugar and UV, EI and FAB-mass spectra, 1H NMR, 13C DEPT NMR, NOE difference measurement, 1H-H COSY and 1H-13C COSY spectral data.

Bilateral sequential lung transplantation for end stage septic lung disease

BACKGROUND

Bilateral sequential lung transplantation (BSLT) has been widely adopted as an alternative to combined heart and lung transplantation for the management of end stage septic lung disease in many transplant centres.

METHODS

A retrospective review was undertaken of the first 32 consecutive patients with septic lung disease to undergo BSLT at the Freeman Hospital.

RESULTS

Between April 1988 and October 1994 32 patients underwent BSLT. Survival at 30 days was 85% and actuarial survival at one year was 70%. Improved pulmonary function was seen in all surviving patients.

CONCLUSION

BSLT for septic lung disease offers comparable survival to heart-lung transplantation, with excellent functional results. Long term results may be superior because the disadvantages of transplanting the heart are avoided.

Recognition of a unique peptide epitope of the mycobacterial and human heat shock protein 65-60 antigen by T cells of patients with recurrent oral ulcers

T cell epitopes of the 65-kD heat shock protein (hsp) were investigated in patients with recurrent oral ulcers (ROU). Peripheral blood mononuclear cells were stimulated with overlapping synthetic peptide (15ers), derived from the sequence of the 65-kD hsp of Mycobacterium tuberculosis. Specific lymphoproliferative responses were stimulated only with peptide 91-105 in ROU, compared with healthy or disease controls (P < 0.01). This was confirmed by studying 760 short term cell lines generated with the 65-kD hsp and then stimulated with the peptides. The frequency of short term cells lines responding to peptide 91-105 in ROU was significantly greater than in healthy (P < 0.0001) or disease controls (P < 0.01). A comparative investigation with the homologous human 60-kD hsp peptide 116-130 also showed significantly greater lymphoproliferative responses in ROU than in healthy (P < 0.01) or disease controls (P < 0.001). The potential involvement of the T cell epitope 91-105 in the pathogenesis of ROU is supported by finding a significant increase in the lymphoproliferative responses stimulated with peptide 91-105 during the stage of ulceration, compared with remission in 9/11 patients studied sequentially (P < 0.05). The results suggest that oral ulceration might be initiated by the microbial hsp peptide 91-105 stimulating the mucosal Langerhans cells, which may generate autoreactive T cell clones primed to the homologous peptide 116-130.

Pentoxifylline, pentifylline, and interferons decrease type I and III procollagen mRNA levels in dermal fibroblasts: evidence for mediation by nuclear factor 1 down-regulation

Pentoxifylline (PTX) is a methylxanthine that exhibits multiple biologic activities, including the inhibition of collagen synthesis by dermal fibroblasts. Because some PTX activities have recently been linked to transcription factor-mediated regulation of gene transcription, we have investigated if PTX acts to inhibit collagen synthesis at a transcriptional locus by measuring procollagen mRNA levels by assaying for the presence of an activator of procollagen gene promoters, nuclear factor (NF)-1. The effects of another methylxanthine, pentifylline (PTF), shown herein to be a tenfold more potent inhibitor of collagen synthesis than PTX, and interferon-alpha, -beta, and -gamma were studied in parallel. Analysis of extracellular protein and RNA from 48-h-treated fibroblasts showed that PTX, PTF, and interferons decreased alpha 1(I), alpha 2(I), and alpha 1(III) procollagens by reducing the steady-state levels of the corresponding procollagen mRNA transcripts. Reduction of procollagen mRNA levels appeared to be dependent on new protein synthesis, as it was prevented by treatment with cycloheximide. Assay for the presence of nuclear NF-1 by gel mobility shift analysis showed that extracts from interferon, PTX, and PTF-treated fibroblasts lacked proteins recognizing the consensus DNA binding sequence for NF-1. Taken together, these observations suggest interferons and methylxanthines may inhibit fibroblast collagen synthesis by a common mechanism requiring new protein synthesis that suppresses procollagen gene transcription through down-regulation of NF-1.

Visual fixation and smooth pursuit eye movement abnormalities in patients with schizophrenia and their relatives

Increasing evidence suggests that smooth pursuit eye movement (SPEM) dysfunction may serve as an endophenotype or genetic marker of schizophrenia. The authors tested SPEM and visual fixation (VF) in 31 patients with schizophrenia, 33 of their first-degree relatives, and 24 patients with major depressive disorder. A high rate of abnormal VF was found in schizophrenic patients and their first-degree relatives, but not in affective disorder patients with or without psychotic features. Rate of VF abnormality distinguished schizophrenic patients from acutely depressed mood disorder patients; SPEM did not. VF and SPEM performance correlated only moderately, suggesting that the pathophysiologies of these two eye movement abnormalities may be partially independent. Implications for identifying a schizophrenia endophenotype are discussed.

Mechanical ventricular assistance for the failing right ventricle after cardiac transplantation

Right ventricular failure secondary to elevated pulmonary vascular resistance (PVR) following orthotopic cardiac transplant is a complication with a high mortality; and patients with high resistance are often not accepted on transplant waiting lists. We describe six cases of right ventricular failure after cardiac transplant managed by right ventricular assist device (RVAD), four of whom died and two patients who survived following life-threatening complications.

Oncostatin M stimulates collagen and glycosaminoglycan production by cultured normal dermal fibroblasts: insensitivity of sclerodermal and keloidal fibroblasts

It is thought that normal fibrotic repair progresses to dermal fibrosis when fibroblasts are activated persistently by chronic exposure to cytokines such as transforming growth factor-beta. However, additional cytokines and mechanisms may play a role in the development of fibrosis. Thus, we examined a recently described T-lymphocyte/macrophage-derived cytokine, oncostatin M, for its effect on the production of collagen and glycosaminoglycan by microcultures of normal dermal, sclerodermal, and keloidal fibroblasts. Treatment with oncostatin M for 48 h induced dose-dependent (1-100 ng/ml) increases in the collagen and glycosaminoglycan production of nine normal fibroblast strains, which in the absence of fetal bovine serum at 100 ng/ml averaged 196% and 244%, respectively. Oncostatin M treatment increased both types I and III procollagens and their mRNA transcripts, as well as levels of hyaluronic acid, chondroitin-4/6 sulfates, and dermatan sulfate, but not fibronectin or general noncollagenous protein synthesis. In contrast, the collagen production of six of eight sclerodermal and keloidal fibroblast strains was essentially unresponsive to oncostatin M treatment, with 100 ng/ml inducing an average increase of only 34% for the eight fibrotic strains. Oncostatin M stimulation of fibrotic fibroblast glycosaminoglycan production was also hyporesponsive, as 100 ng/ml of oncostatin M induced an average increase of only 101%. These results indicate that oncostatin M could function as a stimulator of normal fibrotic repair via activation of fibroblast collagen and glycosaminoglycan synthesis and that the persistent activation of sclerodermal and keloidal fibroblasts is accompanied by a loss of sensitivity to oncostatin M stimulation.

Heat shock protein peptides reactive in patients with Behçet's disease are uveitogenic in Lewis rats

Mycobacterial and homologous human heat shock protein T cell peptide epitopes specific for T lymphocytes in Behçet's disease were investigated for their pathogenicity in Lewis rats. The potential pathogenicity of eight peptides and two controls was assessed by administering the peptides in enriched Freund's adjuvant into the footpads of male Lewis rats. Anterior uveitis which is a major manifestation of Behçet's disease was induced with two out of the four mycobacterial and all four homologous human peptides. The most effective peptides inducing iridocyclitis in 64-75% of rats were peptides with amino acids 336-351 and 136-150, derived from the sequence of the human 60-kD heat shock protein. A few of the rats also showed evidence of focal loss of photoreceptors. These results suggest that selected peptides within heat shock protein 60 kD which function as T cell epitopes in Behçet's disease are capable of inducing uveitis in rats. This supports the view that the peptide T cell determinants may be involved in the pathogenesis of Behçet's disease.

Red cell aplasia resembling Diamond-Blackfan anemia in seven children in a family

PATIENTS AND METHODS

Seven children of the same family with a possible variant of Diamond-Blackfan anemia (DBA) are reported. Five were male siblings, and the other two were their cousins, one male and one female. All were products of consanguineous marriages of healthy parents. All cases occurred within one generation. Anemia was present at birth or shortly after birth. Hepatosplenomegaly was present in all. Four had short stature. Hematological findings included normochromic, normocytic, or macrocytic anemia, marked reticulocytopenia, with initial normal white blood cell and platelet count, and absent or markedly decreased erythroid precursors on bone marrow examination. All were treated initially with prednisolone; in one patient oxymetholone was added.

RESULTS

Three children failed to respond to the initial treatment, and also failed to respond to cyclosporin A and pulse doses of methylprednisolone. Myelofibrosis occurred in two siblings, 9 and 11 years from diagnosis. In two children the disease recurred 9 and 12 years after initial diagnosis.

CONCLUSIONS

Our cases point to a possible variant of DBA characterized by the presence of normochromic normocytic anemia, hepatosplenomegaly, absent skeletal malformations, and unusual long- term complications.

Single lung transplantation with simultaneous contralateral pneumonectomy for cystic fibrosis

A 24-year-old man with cystic fibrosis and marked reduction of volume of the left hemithorax caused by skeletal asymmetry and mediastinal shift underwent successful right single lung transplantation with simultaneous left pneumonectomy. Despite significant preoperative microbiologic contamination, it proved possible to sterilize the pneumonectomy space and no airway complications occurred. Good long-term results have been achieved, and the historic assumption that single lung transplantation is unsuitable for patients with septic lung disease is challenged.

2-substituted thioadenine nucleoside and nucleotide analogues: synthesis and receptor subtype binding affinities (1)

The design, synthesis, and receptor subtype binding affinities of several 2-substituted thioadenosine nucleoside and nucleotide analogues are described. Alkylation of 2-thioadenosine (1) with iodopentenylboronic acid followed by iododeboronation gave 2-((E)-1-iodo-1-penten-5-yl) thioadenosine (9). Compound 1 on treatment with 4-nitrobenzyl bromide and propargyl bromide furnished compounds 3 and 5, respectively. The 5'-monophosphate analogues of compounds 3, 5, 7, and 9 were prepared similarly using 2-thioadenosine 5'-monophosphate (2). Treatment of 1 with bromoethylamine hydrobromide provided 2-[(aminoethyl)thio]adenosine (11) which on coupling with N-succinimidyl 3-(4-hydroxyphenyl)propionate gave 2-[[[3-(4-hydroxyphenyl)propionamido]ethyl]thio]adenosine (12). Iodination of 12 gave 2-[[[3-(4-hydroxy-3-iodophenyl)propionamido]ethyl]thio]adenosine (13). Compounds 3-13 were evaluated for their affinities toward A1 and A2 adenosine receptors in rat brain cortex and striatum, respectively using [3H]DPCPX and [3H]CGS21680 as ligands. The nucleotide analogues 4, 6, 8, and 10 inhibited binding of [3H]DPCPX by 10-20% and of [3H]CGS21680 by 40-50% at a concentration of 100 microM suggesting weak affinity toward adenosine receptors. The nucleoside analogues 3, 5, 7, 9, 12, and 13 inhibited the A2 receptor binding of [3H]CGS21680 with Ki values of 1.2-3.67 microM, while A1 receptor binding of [3H]DPCPX was inhibited with Ki values 10-17 microM. The A1/A2 ratios suggest 4-8-fold A2 receptor selectivity.

Videothoracoscopy in the diagnosis of intrathoracic pathology: early experience

We report our experience using the new technique of videothoracoscopy in the diagnosis of intrathoracic pathology. In the last 12 months, 40 patients (24 male; 16 female) have undergone investigation by this method. Lung biopsy has been performed in 17 patients, pleural biopsy in 20 patients and mediastinal biopsy in three patients. The majority had been referred after other investigations had been inconclusive. All biopsies were diagnostic except one mediastinal biopsy. This early experience suggests that videothoracoscopic biopsy is a well-tolerated technique with high diagnostic yield.

Odor discrimination deficits in schizophrenia: association with eye movement dysfunction

Odor discrimination deficits were found in 80% of 20 schizophrenia patients and in none of the 20 age- and sex-matched comparison subjects. Olfactory discrimination was reliably measured in the patients. Twelve patients in this study also had smooth pursuit eye movement (SPEM) qualitatively recorded. The olfactory discrimination scores were highly correlated to SPEM but not to other clinical measures. This correlation suggests a shared neurobiology, possibly involving working memory.

T cell epitope expression of mycobacterial and homologous human 65-kilodalton heat shock protein peptides in short term cell lines from patients with Behçet's disease

T cell epitopes of the 65-kDa heat shock protein (HSP) were mapped in patients with Behçet's disease (BD), by stimulating T cells with the overlapping synthetic peptides derived from the sequences of the Mycobacterium tuberculosis 65-kDa HSP. Significant lymphoproliferative responses were stimulated with four HSP peptides in BD, as compared with the related disease (recurrent oral ulcers), unrelated disease, and healthy controls (p &lt; 0.05 to 0.005). In order to assess the relative frequency of sensitized lymphocytes by these peptides, 7353 short term cell lines were generated from the lymphocytes of patients and controls. Peptides 111-125, 154-172, and 311-325 (p &lt; 0.001) and peptide 219-233 (p &lt; 0.02) yielded significantly greater frequency of STCL in BD than in healthy and disease controls. All but peptide 154-172 stimulated only the CD4+ subset of T cells, although there was no evidence that reactivity to the selected peptides is restricted by DR2 to DR7 Ag. HLA-B51 is significantly associated with BD, but there was no evidence that B51 was a restricting element, when B51+ patients were compared with B51- patients with BD, and with B51+ healthy control subjects. A comparative investigation was then carried out between the corresponding mycobacterial and human HSP peptides. Similar or higher lympho-proliferative responses were stimulated by the human peptides compared with the mycobacterial peptides. These results suggest that the four peptide determinants within the 65-kDa HSP might be involved in the pathogenesis of BD. Whereas the high microbial load and associated stress proteins found in oral ulceration of BD may initiate an immune response to these conserved epitopes, expression of autoreactive T cell clones might be stimulated by immunodominant T cell epitopes of endogenous HSP which may induce immunopathologic changes.

T cell epitope expression of mycobacterial and homologous human 65-kilodalton heat shock protein peptides in short term cell lines from patients with Behçet's disease

T cell epitopes of the 65-kDa heat shock protein (HSP) were mapped in patients with Behçet's disease (BD), by stimulating T cells with the overlapping synthetic peptides derived from the sequences of the Mycobacterium tuberculosis 65-kDa HSP. Significant lymphoproliferative responses were stimulated with four HSP peptides in BD, as compared with the related disease (recurrent oral ulcers), unrelated disease, and healthy controls (p < 0.05 to 0.005). In order to assess the relative frequency of sensitized lymphocytes by these peptides, 7353 short term cell lines were generated from the lymphocytes of patients and controls. Peptides 111-125, 154-172, and 311-325 (p < 0.001) and peptide 219-233 (p < 0.02) yielded significantly greater frequency of STCL in BD than in healthy and disease controls. All but peptide 154-172 stimulated only the CD4+ subset of T cells, although there was no evidence that reactivity to the selected peptides is restricted by DR2 to DR7 Ag. HLA-B51 is significantly associated with BD, but there was no evidence that B51 was a restricting element, when B51+ patients were compared with B51- patients with BD, and with B51+ healthy control subjects. A comparative investigation was then carried out between the corresponding mycobacterial and human HSP peptides. Similar or higher lympho-proliferative responses were stimulated by the human peptides compared with the mycobacterial peptides. These results suggest that the four peptide determinants within the 65-kDa HSP might be involved in the pathogenesis of BD. Whereas the high microbial load and associated stress proteins found in oral ulceration of BD may initiate an immune response to these conserved epitopes, expression of autoreactive T cell clones might be stimulated by immunodominant T cell epitopes of endogenous HSP which may induce immunopathologic changes.

Heart-lung transplantation combined with correction of interrupted aortic arch

We describe a new technique for heart-lung transplantation in a patient with interrupted aortic arch. The operation was performed in a 21-year-old patient with situs solitus, double-inlet left ventricle, transposition of great arteries, type A interrupted aortic arch, and pulmonary hypertension. One-stage correction of interrupted aortic arch was undertaken using recipient ductal and pulmonary arterial tissues. The early postoperative course was uneventful, with clinical and radiological evidence of satisfactory result. We conclude that it is entirely feasible to undertake heart-lung transplantation in the presence of interrupted aortic arch using this technique, which requires no period of circulatory arrest and results in a tension-free anastomosis.

The reaction of bovine lens alpha A-crystallin with aspirin

Acetylation of the lysines of bovine lens alpha A-crystallin has been examined after 0-48-hr incubations of whole alpha-crystallins in 100 mM aspirin. The alpha A-crystallins were isolated after the incubation, proteolytically digested into peptides which were separated by reversed phase HPLC and analysed by mass spectrometry. For the reaction conditions used in this investigation, acetylated lysyl residues were the principal products. The extent of acetylation was quantified from the intensities of the peaks in the fast atom bombardment mass spectra of the modified and unmodified peptides. The modified lysine containing peptides demonstrated that all seven lysyl residues of alpha A-crystallin reacted with aspirin; the extent of acetylation at each lysyl residue varied. Plots of the extent of acetylation vs. time were used to calculate rate constants for the reaction at each lysyl residue. The rate constant for the acetylation of Lys 166, the most reactive, was about seven times greater than for Lys 88, the least reactive. These rate constants were used to calculate the yield of predicted products for the reaction of alpha-crystallin with therapeutic concentrations of aspirin. Comparison of the yield of acetylated alpha-crystallin with the yield of carbamylated alpha-crystallin that might occur due to renal failure indicates that aspirin is not likely to be an effective inhibitor of cataract due to carbamylation of lysyl residues.

[Outcome of conservative treatment of high-degree vesicoureteral reflux]

We performed a retrospective study to evaluate the results of a nonsurgical approach of primary high grade vesicoureteral reflux (VUR). 241 patients (209 III and 32 IV) were reviewed during and average time of 9.4 years. 55% of them were under 6 months and 52% had bilateral reflux (50% III and 63% IV). During the observation period spontaneous resolution of reflux was observed in 126 (60%) with grade III at 5 years and 26% in patient with grade IV at 4 years. In both grades the duration of persistent reflux was analyzed using life-table method. When age at presentation was compared with duration of reflux there was a shorter time of reflux in those patients presenting from age 0 to 6 months. New renal scars developed in 5 patients during the period of observational therapy. We conclude that high grade VUR can resolve over a protracted interval. On basis of this analysis, we advocate the surgical correction in these patients after 5-year period to grade III and 2-year to grade IV.

Penetration of ciprofloxacin into pleural fluid

The penetration of oral 1000 mg/day ciprofloxacin into pleural fluid is investigated in 15 patients with exudative pleural effusion. After 4 days of ciprofloxacin therapy ciprofloxacin concentrations were measured in plasma and pleural exudate simultaneously by high-performance liquid chromatography (HPLC). Mean serum ciprofloxacin level was 1.58 +/- 0.91 mg/L and mean pleural exudate concentration was 1.00 +/- 0.59 mg/L. The concentrations achieved were all above the MIC90 of the majority of Gram-positive and Gram-negative pathogens. It is concluded that ciprofloxacin penetrates well into the pleural fluid.