Living with suicidal thoughts: A scoping review

BACKGROUND

There is a significantly higher number of people experiencing severe levels of suicidal thoughts compared to that of suicidal deaths and suicide attempts. In suicide prevention research, there is a shift towards greater emphasis on people's experiences of living with suicidal thoughts. This can expand the existing evidence base, which is dominated by a biomedical approach. The aim of this review was to summarise and disseminate existing research on the lived experiences of living with suicidal thoughts.

METHODS

A scoping review by Arksey & O'Malley consisting of six stages: (1) formulating the research question, (2) identifying relevant studies, (3) selecting studies, (4) mapping data, (5) summarising the results and (6) consulting stakeholders. PubMed, PsycINFO and CINAHL were searched for studies in English, Danish, Swedish and Norwegian. Peer-reviewed articles examining people's experiences of living with suicidal thoughts using qualitative methods were included. The search was supplemented with a citation pearl search in the Web of Science database. Twenty-eight studies were included.

RESULTS

The findings were organised under two thematic headings: (a) the significance of social connections and (b) a loss of the personal self.

CONCLUSION

There is a need for further qualitative research of people's experiences of living with suicidal thoughts from an everyday life perspective. Awareness about social connections and attachment in mental health prevention and governance is crucial. Trauma-informed care could be a useful approach to prevent suicidal thoughts as the review found that many participants had traumatic experiences in both childhood and adulthood. As part of the treatment of suicidal thoughts, it might be useful to have a focus on narrative and communicative methods and their clinical application.

Recurrence of sarcoid granulomas in lung transplant recipients is common and does not affect overall survival

BACKGROUND

Sarcoidosis represents 2,5% of all indications for lung transplantation and criteria are generally assumed to be the same as for pulmonary fibrosis. Recurrence of granulomas in transplanted lungs has earlier been proved to derive from recipient immune cells, but its role in relation to lung function and overall survival after lung transplantation remains uncertain.

OBJECTIVE

To identify recurrent granuloma in transbronchial biopsies in patients receiving lung transplant because of sarcoidosis, and relate the findings to overall survival and lung function.

DESIGN

A total of 620 patients were transplanted at this centre from 1992 until august 2012. This study comprised all patients (n=25) transplanted due to pulmonary sarcoidosis. Lung functions, trans-bronchial biopsies, and survival were compared in patients with and without recurrence of granulomas. Granulomas were defined as non-necrotizing epitheloid granulomas with multinucleated giant cells according to standard criteria (formation of epitheloid giant cells) without presence of infection.

CONCLUSIONS

Approximately 30% of lung transplant recipients due to sarcoidosis have recurrence of sarcoid granulomas. Recurrence of granulomas does not affect overall survival or lung function.

Mutation in APOA1 predicts increased risk of ischaemic heart disease and total mortality without low HDL cholesterol levels

OBJECTIVES

To determine whether mutations in APOA1 affect levels of high-density lipoprotein (HDL) cholesterol and to predict risk of ischaemic heart disease (IHD) and total mortality in the general population.

BACKGROUND

Epidemiologically, risk of IHD is inversely related to HDL cholesterol levels. Mutations in apolipoprotein (apo) A-I, the major protein constituent of HDL, might be associated with low HDL cholesterol and predispose to IHD and early death.

DESIGN

We resequenced APOA1 in 190 individuals and examined the effect of mutations on HDL cholesterol, risk of IHD, myocardial infarction (MI) and mortality in 10 440 individuals in the prospective Copenhagen City Heart Study followed for 31 years. Results were validated in an independent case-control study (n = 16 035). Additionally, we determined plasma ratios of mutant to wildtype (WT) apoA-I in human heterozygotes and functional effects of mutations in adenovirus-transfected mice.

RESULTS

We identified a new mutation, A164S (1 : 500 in the general population), which predicted hazard ratios for IHD, MI and total mortality of 3.2 [95% confidence interval (CI): 1.6-6.5], 5.5 (95% CI: 2.6-11.7) and 2.5 (95% CI: 1.3-4.8), respectively, in heterozygotes compared with noncarriers. Mean reduction in survival time in heterozygotes was 10 years (P < 0.0001). Results for IHD and MI were confirmed in the case-control study. Furthermore, the ratio of mutant S164 to WT A164 apoA-I in plasma of heterozygotes was reduced. In addition, A164S heterozygotes had normal plasma lipid and lipoprotein levels, including HDL cholesterol and apoA-I, and this finding was confirmed in adenovirus-transfected mice.

CONCLUSIONS

A164S is the first mutation in APOA1 to be described that predicts an increased risk of IHD, MI and total mortality without low HDL cholesterol levels.

Complement factor H deficiency and endocapillary glomerulonephritis due to paternal isodisomy and a novel factor H mutation

Complement factor H (CFH) is a regulator of the alternative complement activation pathway. Mutations in the CFH gene are associated with atypical hemolytic uremic syndrome, membranoproliferative glomerulonephritis type II and C3 glomerulonephritis. Here, we report a 6-month-old CFH-deficient child presenting with endocapillary glomerulonephritis rather than membranoproliferative glomerulonephritis (MPGN) or C3 glomerulonephritis. Sequence analyses showed homozygosity for a novel CFH missense mutation (Pro139Ser) associated with severely decreased CFH plasma concentration (<6%) but normal mRNA splicing and expression. The father was heterozygous carrier of the mutation, but the mother was a non-carrier. Thus, a large deletion in the maternal CFH locus or uniparental isodisomy was suspected. Polymorphic markers across chromosome 1 showed homozygosity for the paternal allele in all markers and a lack of the maternal allele in six informative markers. This combined with a comparative genomic hybridization assay demonstrated paternal isodisomy. Uniparental isodisomy increases the risk of homozygous variations in other genes on the affected chromosome. Therefore, we analyzed other susceptibility genes on chromosome 1 and found no sequence variation in membrane cofactor protein, but homozygosity for the common deletion of CFH-related proteins 1 and 3, which may contribute to the early onset of disease.

Renal cell apoptosis in human lupus nephritis: a histological study

Nuclear autoantigens from apoptotic cells are believed to drive the immunological response in systemic lupus erythematosus (SLE). Conflicting data exist as to the possible renal origin of apoptotic cells in SLE patients with nephritis. We assessed the level of renal cell apoptosis in kidney biopsies from 35 patients with lupus nephritis by means of terminal deoxynucleotidyl-transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-digoxigenin nick end labeling (TUNEL). Five samples of normal kidney tissue served as control specimens. We did not observe apoptotic glomerular cells in any of the control or nephritis biopsies. Scarce apoptotic tubular cells were seen in 13 of 35 (37%) of the nephritis specimens and in two of five (40%) of the control sections. Within the SLE cohort, patients with TUNEL-positive tubular cells in their renal biopsies had significantly higher activity index scores for tubulointerstitial mononuclear cell infiltration than patients without apoptotic tubular cells in their biopsies ( P = 0.01). Furthermore, the level of tubular cell apoptosis displayed a statistically significant, positive correlation with the activity index score for mononuclear cell infiltration (rs = 0.472, P = 0.004) but not with scores for other activity or chronicity index components. These observations indicate that the degree of tubular cell apoptosis correlates with the severity of tubulointerstitial inflammation in SLE-associated nephritis. However, our findings do not suggest that apoptotic renal cells constitute a quantitatively important source of auto-antibody-inducing nuclear auto-antigens in human lupus nephritis.

Adhesion of T and B lymphocytes to mouse atherosclerotic aortas: Association with lesion topology and VCAM‐1 expression

OBJECTIVE

Although T and B lymphocytes accumulate in atherosclerotic lesions and play a key role in their growth, the mechanisms involved in the adhesion and recruitment of T and B lymphocytes by the lesions have not been resolved. The aim of this study was to compare T and B lymphocyte adhesion to atherosclerotic arteries and to test the role of VCAM-1 and ICAM-1.

MATERIAL AND METHODS

T and B lymphocytes were labelled with red and green fluorescent dyes and incubated with freshly isolated aortas from apolipoprotein-E-deficient mice. In some experiments the aortas were pre-incubated with specific monoclonal antibodies. After washing, the adhering cells were detected by confocal laser scanning microscopy.

RESULTS

The number of T and B lymphocytes that adhered to the aortic intimal surface was similar in both lesioned and non-lesioned areas and in the shoulder region of the lesions. However, the adhesion of T and B lymphocytes was significantly higher in the shoulder regions compared with the lesioned (p<0.0001) and non-lesioned areas of the aorta (p<0.0001). After pre-incubation of the aortas with antibodies against VCAM-1 or ICAM-1, the lymphocyte adhesions in lesioned areas were 42 % (p = 0.04) and 55 % (p = 0.17), respectively, of those in lesioned areas that had been pre-incubated with a control antibody. However, although VCAM-1 protein expression was most pronounced in the shoulder region, the lymphocyte adhesions in the shoulder region and in non-lesioned areas were unaffected by pre-incubation with VCAM-1 antibodies.

CONCLUSIONS

The results suggest that adhesion of T and B lymphocytes to mouse aortic endothelium is similar, is affected by lesion topology and is dependent on VCAM-1 expression over the core of atherosclerotic lesions.

A foot and mouth disease simulation exercise involving the five Nordic countries

Simulation exercises are considered a very valuable tool for testing contingency plans established for the control and eradication of rapid spreading animal diseases such as foot and mouth disease, classical swine fever and avian influenza. An inter-Nordic simulation exercise was conducted in 2005 with the objective of testing the national foot and mouth disease contingency plans adopted respectively by Denmark, Finland, Iceland, Norway and Sweden. The Central Veterinary Administrations of the five countries jointly prepared a scenario which involved about 40 livestock holdings, 4 reindeer flocks, 6 slaughterhouses and approximately 500 people. An Excel spreadsheet with information on the events to take place and the timetable to follow during the exercise was a valuable tool for ensuring that the exercise was kept on track. The evaluation of the exercise dealt both with inter-Nordic activities and the activities of individual countries.

Cardiac sarcoidosis and heart transplantation: a report of four consecutive patients

Heart transplantation (HTx) is a well-established treatment for severe cardiac failure. However, HTx for cardiac sarcoidosis is rare; less than 80 patients have been reported worldwide. In many patients, the diagnosis was not made prior to HTx. The aim of this study was to describe the use of HTx in the treatment of severe cardiac sarcoidosis. The series was comprised of four Caucasian patients (1 male, 3 females), aged 25-57 years. HTx were performed in the period 1990-2006. None of the patients had clinically overt extra-cardiac sarcoidosis. In one patient the diagnosis of sarcoidosis was proven prior to HTx. In three patients, all with dilated cardiomyopathy due to myocardial sarcoidosis, the final diagnosis was obtained by examination of the explanted heart. Arrythmias (supraventricular and ventricular), heart block, mitral valve insufficiency and dilated cardiomyopathy were prominent clinical features. None of the patients had recurrence of sarcoid disease in the allograft. Two patients are long-term survivors and two are deceased, one of primary graft failure, the other from Cytomegalovirus myocarditis. In conclusion, HTx is a viable treatment for cardiac sarcoidosis with end stage cardiac failure. Cardiac sarcoidosis is difficult to diagnose. Myocardial biopsy has a low diagnostic sensitivity. However, when the newest non-invasive diagnostic methods, including magnetic resonance imaging and positron emission tomography, are applied, an endomyocardial biopsy should not be mandatory to make a diagnosis of cardiac sarcoidosis.

Aspergillus infection in lung transplant patients: incidence and prognosis

Lung transplant recipients experience a particularly high incidence of Aspergillus infection in comparison with other solid-organ transplantations. This study was conducted to determine the incidence of Aspergillus colonisation and invasive aspergillosis, and the impact on long-term survival associated with Aspergillus infection. A retrospective study of 362 consecutive lung transplant patients from a single national centre who were transplanted 1992-2003 were studied. Twenty-seven patients were excluded due to incomplete or missing files. A total of 105/335 (31%) patients had evidence of Aspergillus infection (colonisation or invasion), including 83 (25%) patients with colonisation and 22 (6%) patients with radiographic or histological evidence of invasive disease. Most of the infections occurred within the first 3 months after transplantation. Cystic fibrosis (CF) patients had higher incidences of colonisation and invasive disease [15 (42%) and 4 (11%) of 36 patients] than non-CF patients [68 (23%) and 18 (6%) of 299 patients] (P = 0.01). Invasive aspergillosis was associated with 58% mortality after 2 years, whereas colonisation was not associated with early increased mortality but was associated with increased mortality after 5 years compared to non-infected patients (P < 0.05). An analysis of demographic factors showed that donor age [OR 1.40 per decade (95% CI 1.10-1.80)], ischaemia time [OR 1.17 per hour increase (95% CI 1.01-1.39)], and use of daclizumab versus polyclonal induction [OR 2.05 (95% CI 1.14-3.75)] were independent risk factors for Aspergillus infection. Invasive aspergillosis was associated with early and high mortality in lung transplant patients. Colonisation with Aspergillus was also associated with a significant increase in mortality after 5 years. CF patients have a higher incidence of Aspergillus infection than non-CF patients.

Morphometric examination of native lungs in human lung allograft recipients

The aim of the study was to estimate the degree of lung damage in patients with alpha(1)-antitrypsin (alpha1AT) deficiency, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) at the time of lung transplantation. Using unbiased stereological methods, lung-, bronchial- and vessel-volume, capillary length, and alveolar surface area and densities were estimated in recipient lungs from 21 consecutive patients with pre-transplant diagnoses including COPD (n=7), alpha1AT deficiency (n=6) and CF (n=8). Six unused adult donor lungs served as controls. Information relating to patient demography and pre-transplant lung function was obtained by retrospective chart review. Disease groups differed significantly with respect to demographics and pre-transplant lung function. Total lung volume was similar in all groups. Bronchial volume was significantly larger in CF patients compared to the control group (p<0.0001) and to the other two diagnostic groups: alpha1AT deficiency (p=0.0001) and COPD (p<0.0001). Alveolar surface density and capillary length density were significantly lower in patients with alpha1AT deficiency and COPD compared to controls (p<0.0001, respectively) and to patients with CF (p<0.0002, respectively). There were no correlations between clinical lung function and morphometric measurements. We conclude that unbiased microscopic stereological morphometry is an evolving science with the potential to elucidate pulmonary disease pathogenesis.

Recurrent sarcoid granulomas in a transplanted lung derive from recipient immune cells

From 1992-2004, single lung transplantation has been performed in seven patients with end-stage pulmonary sarcoidosis at the Danish National Centre for Lung Transplantation. The objective was to assess whether recurrent sarcoid granulomas in the lung graft are derived from recipient or donor immune cells. Three patients had sarcoid recurrence in the lung graft, but none had clinically overt extra-thoracic sarcoidosis. Graft sex-mismatch was present in one patient, a 52-yr-old female having a lung graft from a male donor. In order to discriminate between recipient and donor cells fluorescence in situ hybridisation (FISH), using probes for both X- and Y-chromosomes, was applied on transbronchial lung biopsies (TBB) from the lung graft containing sarcoid granulomas. The recipient's explanted lung contained multiple active sarcoid granulomas. TBB from the implanted donor lung 5 months after transplantation showed sarcoid granulomas. FISH showed that the immune cells in the granulomas were X-chromosome positive and Y-chromosome negative and, therefore, were derived from the recipient. In conclusion, the results indicate that recurrent sarcoid granulomas in the transplanted lung are derived from recipient's immune cells, having colonised the lung allograft.

Macrophages overloaded with tissue debris in Wegener's granulomatosis

OBJECTIVES

To analyse some scavenging related molecules in Wegener's granulomatosis (WG) macrophages.

METHODS

Immunohistochemical staining of lung, nasopharynx, and skin for macrophage markers related to scavenging (macrophage scavenger receptor MARCO, collagenase-1 and gelatinase-B), formation of multinuclear foreign body giant cells (ADAM 9/meltrin-gamma and ADAM 12/meltrin-alpha), and cell debris derived from neutrophils, endothelial cells and mast cells (specific granule protein 28 (SGP28), von Willebrand factor (vWF) and mast cell tryptase, respectively). TechMate staining robot and biotin-streptavidin protocol were used.

RESULTS

Some macrophages were activated and expressed collagenase-1 and gelatinase-B. Approximately 5% of macrophages expressed scavenger receptor, whereas 20-30% were meltrin positive. Interstitial and granuloma associated macrophages and giant cells contained partly undigested, immunoreactive SGP28-, vWF- and tryptase-positive cell rests and collagenous matrix. Lymphocytic follicles with germinal centres were found in the same areas.

CONCLUSION

In WG tissue lesions macrophage and giant cells seem to be overwhelmed by the bulk to be scavenged. Despite cellular activation and continuing maturation to professional scavenger receptor (MARCO) and meltrin positive multinuclear giant cells combined with an organisation into granulomas, macrophages still contain partially undigested cell and tissue rests. This necrotic and damaged self may be the driving force for the formation of giant cell ("foreign body") granulomas. This, together with the local formation of secondary lymphatic follicles (with germinal centres), indicates active local antigen processing and presentation.

Bronchial arterial devascularization. An experimental study in pigs

OBJECTIVE

The lungs have dual blood supply: The bronchial and the pulmonary circulation. The importance of bronchial circulation is disputed. The purpose of this study was to establish an experimental model to examine the importance of the bronchial artery.

DESIGN

Comparative porcine experimental study. The surgical technique was evaluated in group A (n = 9). Group B (n = 8) underwent left bronchial arterial devascularization. In group C (n = 9) the left principal bronchus was devascularized, transsected, and reanastomosed. In groups B and C bronchial mucosal blood flow was studied with laser-Doppler velocimetry. Devascularization was controlled by angiography at section, and specimens were examined with conventional histology and scanning electron microscopy. The right bronchus served as control.

RESULTS

In group B devascularization caused considerable, yet insignificant reduction in bronchial mucosal blood flow index (p = 0.1282) postoperatively, and after 1 week (p = 0.0678), insignificant histologic (p > 0.2) changes, and no scanning electron microscopy differences. In group C devascularization with bronchial transsection caused significant reduction in mucosal blood flow index (p = 0.0277) postoperatively and after 1 week (p = 0.0277), significant histologic changes (p = 0.0277), and insignificant (p = 0.069) changes in scanning electron microscopy.

CONCLUSION

Bronchial arterial devascularization with transsection caused significant physiologic and morphologic changes, and a model with bronchial devascularization should include transsection.

Cloning and characterization of the cyclic guanosine monophosphate-inhibited phosphodiesterase PDE3A expressed in mouse oocyte

In the preovulatory follicle, oocyte meiotic resumption occurs soon after the LH surge and is associated with a decrease in cAMP. Inhibition of cAMP degradation blocks germinal vesicle breakdown as well as activation of meiotic promoting factor, both hallmarks of reentry into the cell cycle. In situ and pharmacological analysis of rodent ovaries suggested the presence of a phosphodiesterase 3 (PDE3) in the germ cell but not the somatic cell compartment. Here we have investigated the structure and properties of the PDE form expressed in mouse oocytes. Polymerase chain reactions using a mouse oocyte cDNA library as a template, and primers based on the conserved sequence of rat and human PDE3As, yielded partial fragments corresponding to mouse PDE3A. Further screening of the mouse oocyte cDNA library and subsequent ligation of individual cDNA clones yielded PDE3A cDNA containing the entire coding region of mouse PDE3A. To determine the kinetic properties of this PDE, the cDNAs encoding the full-length PDE3A and NH(2)-truncation forms Delta 1 (Delta346aa) and Delta 2 (Delta608aa) were expressed in mouse Leydig tumor cells. Whereas the full-length recombinant protein was always found in the particulate fraction, the Delta 1 and Delta 2 truncated PDE3As were recovered mostly in the soluble fraction. The Michaelis constant values for hydrolysis of cAMP of PDE3A Delta 1 and PDE3A Delta 2 were similar to those of intact full-length PDE3A or oocyte PDE (0.2-0.5 microM). More importantly, there was good correlation between the rank of potency of selective and nonselective compounds in inhibiting recombinant PDE3A or PDE activity derived from cumulus-oocyte complexes and in blocking resumption of meiosis. These data provide evidence that the PDE expressed in the oocyte is a soluble form of PDE3A and that activity of this enzyme is involved in the control of resumption of meiosis.

Macrophage and lymphocyte chimerism in bronchoalveolar lavage cells from human lung allograft recipients

BACKGROUND

Chimerism is suggested to predict a more favourable prognosis in solid organ transplantation.

MATERIAL AND METHOD

Forty-eight bronchoalveolar lavages from 10 patients (5 females and 5 males) who had received sex-mismatched donor lungs were monitored for varying periods of time, of up to 2 years, at regular intervals (median 3.0 (0.5-24) months). To investigate the chimerism in macrophages and lymphocytes in bronchoalveolar lavage cells a cloned 2.12 kilobase large biotinylated Y-chromosome-specific DNA-probe was used for in situ hybridization.

RESULTS

Donor macrophages disappeared in seven patients within the first 6 months after surgery (median 3.0 (1-6) months). But 15% donor macrophages could be detected in one patient 1 year and 10% in 2 patients two years after surgery. Donor lymphocytes disappeared in all patients within 3 months (median 1 (0.5-3) months). There was no correlation between periods or severity of acute rejection and percentage of donor macrophages and donor lymphocytes in bronchoalveolar lavage. None of the patients developed obliterative bronchiolitis.

CONCLUSION

Macrophage chimerism in lung may exist for several years. Whilst our results do not elucidate the role of local macrophage chimerism, they do not currently support the view that chimerism prevents rejection.

Bronchial transsection and reanastomosis in pigs with and without bronchial arterial circulation

BACKGROUND

The bronchial artery may be vital to the bronchi and lung parenchyma, but results of lung transplantation have raised doubts. This study was performed to examine the effect of bronchial arterial devascularization on bronchial morphology after bronchial transsection and reanastomosis.

METHODS

In 6 pigs (study group), the left main bronchus was transsected, reanastomosed, and devascularized. Six control pigs had the same operation without devascularization. After 1 week, bronchial arterial angiography was performed, and specimens were examined with conventional histology and scanning electron microscopy.

RESULTS

Histology showed significant changes (inflammation, edema, and fibrosis) in bronchi and lung parenchyma of the study group compared with the unoperated side (p = 0.028) and with the control group (p = 0.050). Scanning electron microscopy showed significant ciliary denudation in the study group's left bronchus compared with the unoperated side (p = 0.043) and with the control group (p = 0.0071).

CONCLUSIONS

The loss of cilia of the bronchial epithelium and the occurrence of inflammation, edema, and fibrosis in bronchi and lung parenchyma 1 week postoperatively were significantly related to the absence of the bronchial arterial circulation.

Effects of L-arginine on vascular smooth muscle cell proliferation and apoptosis after balloon injury

Nitric oxide (NO) inhibits neointimal formation in experimental models of restenosis, but the mechanisms have not been fully elucidated. This study examined whether the beneficial effect of L-arginine, the physiological NO precursor, was associated with alteration of the apoptotic and proliferative activities of vascular smooth muscle cells (VSMCs) in the vessel wall after arterial injury. Balloon injury was performed in the rat carotid-artery injury model. Rats were treated with L-arginine (2.25% in the drinking water) or normal drinking water, and sacrificed at 1, 2 and 14 days postinjury. Apoptosis was assessed by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick-end labeling (TUNEL), and proliferation by proliferating cell nuclear antigen (PCNA) immunohistochemistry. Treatment with L-arginine increased the luminal area at 14 days postinjury (0.26 +/- 0.03 mm2 vs 0.14 +/- 0.04 mm2; p < 0.05), and this effect was attributable to a reduction in neointimal formation (0.11 +/- 0.03 mm2 vs 0.23 +/- 0.04 mm2; p < 0.05), while L-arginine did not affect vascular remodeling, as indicated by the total vessel area. The decreased neointimal area at 14 days after balloon injury contained a reduced percentage of TUNEL positive (0.1 +/- 0.1% vs 2.0 +/- 0.6%; p < 0.05), and PCNA positive (13.0 +/- 2.6% vs 27.2 +/- 5.9%; p < 0.05) nuclei, respectively. L-arginine did not influence the apoptotic or proliferative activities of VSMCs at earlier time points postinjury. The favourable effect of L-arginine in the rat model of arterial injury is associated with inhibition of VSMC proliferative activity in the vessel wall and is not explained by increased VSMC apoptosis.

Apoptosis and formation of peroxynitrite in the lungs of patients with obliterative bronchiolitis

BACKGROUND

Obliterative bronchiolitis (OB) is the principal long-term complication of lung and heart-lung transplantation. OB is characterized histologically by inflammation, epithelial cell loss, fibrosis, and obliteration of the terminal airways. The contribution of apoptosis and peroxynitrite formation in OB was examined and assessed whether immunohistochemical markers of these reactions in transbronchial biopsy specimens were predictive of OB development.

METHODS

Pulmonary tissue samples from lung transplant recipients with OB (n = 5) or without OB (control group; n = 7) were investigated by in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and nitrotyrosine immunohistochemistry. Furthermore, TUNEL and nitrotyrosine expression was compared between matched transbronchial biopsy specimens from the two patient groups.

RESULTS

Sections with active OB displayed a significantly increased number of TUNEL-positive epithelial cells and macrophages compared with very little TUNEL in control specimens. TUNEL was almost absent in inactive OB. Nitrotyrosine was detected in all samples of pulmonary tissue, but nitrotyrosine expression was more intense in patients with active OB. There was no apparent temporospatial correlation of TUNEL and nitrotyrosine expression, and in matched transbronchial specimens, these immunohistochemical markers failed to identify patients with imminent risk of developing OB.

CONCLUSIONS

Apoptosis contributes to the pathophysiology of active OB but is apparently not directly paralleled by tissue peroxynitrite formation. In transbronchial biopsy specimens, markers of apoptosis and peroxynitrite formation are not valid predictors of OB and more studies are required to deliniate the role of these mechanisms in pulmonary allograft rejection.

ACE-inhibition promotes apoptosis after balloon injury of rat carotid arteries

OBJECTIVE

Angiotensin II stimulates vascular smooth muscle cell (VSMC) growth, and is considered to be an important mediator of intimal thickening after vascular injury. Recent evidence has indicated that VSMC apoptosis plays a major role in the response to balloon injury, and we therefore examined the effect of angiotensin converting enzyme (ACE)-inhibition on VSMC apoptosis and vascular lesion formation in the rat model of balloon injury.

METHODS

Male Sprague-Dawley rats were subjected to carotid artery balloon injury and randomised to a standard diet or a diet supplemented with 1 mg/ml captopril in the drinking water. Animals were sacrificed 2 and 14 days after injury for assessment of apoptosis and proliferation by in situ terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL) and proliferating cell nuclear antigen (PCNA) immunohistochemistry, respectively. At 14 days post injury, vessel cross-sections were subjected to microscopic morphometry and total cell numbers were determined.

RESULTS

At 2 days after balloon injury, captopril-treated animals displayed a significant increase in the percentage of TUNEL-positive VSMCs in the medial area (12 +/- 4% vs. 1 +/- 1%; P < 0.05) as compared to controls. This increase in early apoptosis was associated with decreased intimal cellularity 14 days post injury (238 +/- 47 cells/cross-section vs. 449 +/- 75 cells/cross-section; P < 0.05), and a reduction of neointimal formation (0.13 +/- 0.02 mm2 vs. 0.23 +/- 0.04 mm2; P < 0.05). The fraction of PCNA-positive VSMCs per cross-section 2 or 14 days after injury was not significantly altered by captopril administration.

CONCLUSION

Captopril inhibits neointimal formation in the rat model of arterial injury by mechanisms involving induction of VSMC apoptosis.

A humanized model for multiple sclerosis using HLA-DR2 and a human T-cell receptor

Multiple sclerosis (MS) is a complex chronic neurologic disease with a suspected autoimmune pathogenesis. Although there is evidence that the development of MS is determined by both environmental influences and genes, these factors are largely undefined, except for major histocompatibility (MHC) genes. Linkage analyses and association studies have shown that susceptibility to MS is associated with genes in the human histocompatibility leukocyte antigens (HLA) class II region, but the contribution of these genes to MS disease development less compared with their contribution to disorders such as insulin-dependent diabetes mellitus. Due to the strong linkage disequilibrium in the MHC class II region, it has not been possible to determine which gene(s) is responsible for the genetic predisposition. In transgenic mice, we have expressed three human components involved in T-cell recognition of an MS-relevant autoantigen presented by the HLA-DR2 molecule: DRA*0101/DRB1*1501 (HLA-DR2), an MHC class II candidate MS susceptibility genes found in individuals of European descent; a T-cell receptor (TCR) from an MS-patient-derived T-cell clone specific for the HLA-DR2 bound immunodominant myelin basic protein (MBP) 4102 peptide; and the human CD4 coreceptor. The amino acid sequence of the MBP 84-102 peptide is the same in both human and mouse MBP. Following administration of the MBP peptide, together with adjuvant and pertussis toxin, transgenic mice developed focal CNS inflammation and demyelination that led to clinical manifestations and disease courses resembling those seen in MS. Spontaneous disease was observed in 4% of mice. When DR2 and TCR double-transgenic mice were backcrossed twice to Rag2 (for recombination-activating gene 2)-deficient mice, the incidence of spontaneous disease increased, demonstrating that T cells specific for the HLA-DR2 bound MBP peptide are sufficient and necessary for development of disease. Our study provides evidence that HLA-DR2 can mediate both induced and spontaneous disease resembling MS by presenting an MBP self-peptide to T cells.

Pentoxifylline inhibits neointimal formation and stimulates constrictive vascular remodeling after arterial injury

Pentoxifylline (PTX) is a phosphodiesterase inhibitor used in the treatment of peripheral vascular disease, and this agent can suppress inflammatory vascular damage. Inflammation has been implicated in vascular lesion formation, and we examined the effects of PTX in a model of arterial injury. Sprague-Dawley rats were treated with intraperitoneal PTX (75 mg/kg/day) or saline starting 3 days before carotid balloon injury, and killed 24 h or 14 days later. Carotid arteries were analyzed by cross-sectional morphometry, immunostaining for proliferating cell nuclear antigen (PCNA) and subjected to terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). Moreover, the effects of PTX on vascular smooth-muscle cell (VSMC) migration and production of collagen types I, IV, and VI were examined in vitro. At 14 days after balloon injury, PTX reduced the neointimal area (0.074+/-0.001 vs. 0.172+/-0.003 mm2; p<0.001), media area (0.143+/-0.001 vs. 0.176+/-0.001 mm2; p<0.01), intima/media ratio (0.50+/-0.02 vs. 0.99+/-0.12; p<0.001), and total vessel area (0.601+/-0.010 vs. 0.744+/-0.011 mm2; p<0.01). The lumen area, PCNA expression, and TUNEL were similar in the two treatment groups, whereas the neointimal cell density was increased by PTX (3,476+/-504 cells/mm2 vs. 2,215+/-232 cells/mm2; p<0.05). In vitro, PTX inhibited VSMC production of collagen type I in a concentration-dependent manner and did not influence VSMC migration. We conclude that PTX inhibits neointimal formation and induces constrictive vascular remodeling in the rat model of balloon injury by mechanisms involving decreased VSMC collagen type I production.

Effect of allopurinol on hypoxia-induced modification of the NMDA receptor in newborn piglets

The present study tests the hypothesis that pretreatment with allopurinol, a xanthine oxidase inhibitor, will prevent modification of the NMDA receptor during cerebral hypoxia in newborn piglets. Eighteen newborn piglets were studied. Six normoxic control animals were compared to six untreated hypoxic and six allopurinol (20 mg/kg i.v.) pretreated hypoxic piglets. Cerebral hypoxia was induced by lowering the FiO2 to 0.05-0.07 for 1 hour and tissue hypoxia was confirmed biochemically by the measurement of ATP and phosphocreatine. Brain cell membrane Na+,K+-ATPase activity was determined to assess membrane function. Na+,K+-ATPase activity was decreased from control in both the untreated and treated hypoxic animals (46.0+/-1.0 vs 37.9+/-2.5 and 37.3+/-1.4 micromol Pi/mg protein/hr, respectively, p < 0.05). [3H]MK-801 binding was determined as an index of NMDA receptor modification. The receptor density (Bmax) in the untreated hypoxic group was decreased compared to normoxic control (1.09+/-0.17 vs 0.68+/-0.22 pmol/mg protein, p < 0.01). The dissociation constant (Kd) was also decreased in the untreated group (10.0+/-2.0 vs 4.9+/-1.4 nM, p < 0.01), indicating an increase in receptor affinity. However, in the allopurinol treated hypoxic group, the Bmax (1.27+/-0.09 pmol/mg protein) was similar to normoxic control and the Kd (8.1+/-1.2 nM, p < 0.05) was significantly higher than in the untreated hypoxic group. The data show that the administration of allopurinol prior to hypoxia prevents hypoxia-induced modification of the NMDA receptor-ion channel binding characteristics, despite neuronal membrane dysfunction. By preventing NMDA receptor-ion channel modification, allopurinol may produce a neuromodulatory effect during hypoxia and attenuate NMDA receptor mediated excitotoxicity.

The porcine bronchial artery. Anastomoses with oesophageal, coronary and intercostal arteries

Information about the existence and anatomy of arterial anastomoses with the porcine bronchial artery is lacking in the literature. Prior to basic physiological investigations in a porcine model related to lung transplantation with bronchial artery revascularisation, this study was designed to examine the anatomy of systemic arterial anastomoses with the bronchial artery system. Twenty pigs were studied in 3 groups. In 2 groups the heart-lung block was removed with all mediastinal structures. One group served for investigation of coronary-bronchial artery anastomoses and one for investigation of oesophageal-bronchial artery anastomoses. The systemic arteries to be examined were cannulated. The inflated heart-lung block was examined macroscopically with Evans blue, and radiographically after contrast injection. In the 3rd group intercostobronchial artery anastomoses were studied radiographically with the heart-lung block in situ. Coronary-bronchial artery anastomoses were demonstrated in 3 of the 5 pigs with an aortic 'pouch' technique, but contrast was very limited in 2 of these 3. Oesophageal arterial anastomoses with bronchial arterial branches and/or the pulmonary veins were demonstrated in 6 of the 7 pigs and more markedly than the coronary-bronchial anastomoses. Intercostobronchial artery anastomoses could not be demonstrated angiographically. It was concluded that the existence of coronary-bronchial and oesophageal-bronchial artery anastomoses in the pig appear to establish an arterial net between the base of the heart and the distal oesophagus. The resemblance to human oesophageal-bronchial artery anastomoses supports use of a porcine model for experimental studies.

Transgenic mouse models of rheumatoid arthritis

A combined analysis of data available in the literature has demonstrated that the strongest association in rheumatoid arthritis (RA) is with DR genes rather than DQ or DP genes. Functional and structural data of RA-associated DR molecules suggest that selective binding of peptides is the molecular basis for this association. The establishment of functional transgenic mice expressing RA-associated HLA class II molecules has proven to be useful in the delineation of the role of these molecules in immune responses possibly related to RA and in the development of humanized models for this disease. Such humanized mice develop arthritis upon immunization with type II collagen (CII), which shows similarities with RA. Interestingly, the immunodominant T-cell determinant in CII is derived from positions 261-273, which overlap with a previously identified CII T-cell epitope restricted by the mouse Aq molecule, which is associated with collagen-induced arthritis. Studies in collagen transgenic mice have shown that recognition of this peptide may lead either to T-cell tolerance or to an arthritogenic response. It is therefore proposed that the T-cell recognition of the CII peptide bound by DR molecules is one of the molecular interactions of critical importance in the development of RA and accordingly also an important target for prevention and treatment of this disease.

Aminoguanidine induces constrictive vascular remodeling and inhibits smooth muscle cell death after balloon injury

We examined the effects of aminoguanidine, an inhibitor of inducible nitric oxide synthase, in the rat model of balloon injury. Arteries were assessed by histomorphometry, and vascular smooth muscle cell death and proliferation were examined 24 h and 14 days after balloon injury by in situ terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) of fragmented DNA and expression of proliferating cell nuclear antigen, respectively. Aminoguanidine decreased the luminal area 14 days after balloon injury (0.19+/-0.04 mm2 vs. 0.35+/-0.02 mmr2; P < 0.005), and this effect was attributable to reduction of the total vessel area, i.e., constrictive vascular remodeling (0.42+/-0.03 mm2 vs. 0.55+/-0.03 mm2; P < 0.005). At 24 h after injury, the percentage of TUNEL-positive cells in the medial layer was reduced by aminoguanidine (2.0+/-1.0% vs. 17.3+/-5.4%; P < 0.05), and the percentage of proliferating cells was increased (18.4+/-5.5% vs. 4.9+/-2.2%; P < 0.05). Aminoguanidine did not influence the density of VSMC nuclei in the injured artery wall, systemic blood pressure or endothelium-dependent vasorelaxation. We conclude, that in the rat model of balloon injury, aminoguanidine induces luminal loss by constrictive vascular remodeling in association with reduced early VSMC death and increased proliferation.

Apoptosis in acute pulmonary allograft rejection and cytomegalovirus infection

Apoptosis is a form of programmed cell death, characterized by activation of endonucleases that cleave DNA into oligonucleosomal fragments, which can be identified by in situ terminal deoxyribonucleotide transferase-mediated dUTP nick-end labeling (TUNEL). This process has recently been implicated in cardiac and hepatic allograft rejection, and we investigated its contribution to acute pulmonary allograft rejection and cytomegalovirus (CMV) pneumonitis by in situ TUNEL of transbronchial biopsy specimens. In situ TUNEL was performed on 70 transbronchial biopsy samples collected from 25 pulmonary allograft recipients for diagnosis of acute rejection or CMV pneumonitis, and the number of apoptotic nuclei/mm2 was correlated with the rejection grade (International Society of Heart and Lung Transplantation classification). During acute pulmonary allograft rejection, apoptotic nuclei were demonstrated in pulmonary parenchymal cells and mononuclear infiltrating cells, and the number of apoptotic cells was positively correlated with the rejection grade. In addition, a marked increase in the density of apoptotic cells was found in pulmonary allografts with CMV pneumonitis. We conclude that apoptosis contributes to cell death during acute pulmonary allograft rejection and CMV infection.

Validity of histopathological grading of articular cartilage from osteoarthritic knee joints

OBJECTIVES

To determine the validity of the histological-histochemical grading system (HHGS) for osteoarthritic (OA) articular cartilage.

METHODS

Human articular cartilage was obtained from macroscopically normal (n = 13) and OA (n = 21) knee joints. Sections of central and peripheral regions of normal samples were produced. Sections of regions containing severe, moderate, and mild OA changes were produced from each OA sample. A total of 89 sections were graded by means of the HHGS (0-14) twice by three observers.

RESULTS

Average scores for regions designated severe (8.64) and moderate (5.83) OA were less than the expected (10-14 and 6-9, respectively) according to the HHGS, whereas average scores for the region designated mild (5.29) OA and central and peripheral regions (2.19) of normal cartilage were higher than expected (2-5 and 0-1, respectively). The HHGS was capable of differentiating between articular cartilage from macroscopically normal and OA joints and between the region designated severe OA and other regions. However, the HHGS did not adequately differentiate between regions designated mild and moderate OA. Values for sensitivity, specificity, and efficiency for all regions varied considerably.

CONCLUSION

The HHGS is valid for normal and severe OA cartilage, but does not permit distinction between mild and moderate OA changes in articular cartilage.

Impact of ubiquinone (coenzyme Q10) treatment on glycaemic control, insulin requirement and well-being in patients with Type 1 diabetes mellitus

AIM

To investigate the effect of ubiquinone (coenzyme Q10) on glycaemic control and insulin requirement in patients with Type 1 diabetes mellitus (DM).

METHODS

We investigated 34 patients with Type 1 DM in a randomized, double-blind, placebo-controlled study. Patients received either 100 mg Q10 or placebo daily for 3 months. The insulin doses were adjusted according to patients' home measurements of blood glucose concentrations and reported experience of hypoglycaemia.

RESULTS

At randomization no differences existed between the Q10 and the placebo groups in age, body mass index (BMI), HbA1c, daily insulin dose or mean daily blood glucose concentration. Serum Q10 concentration increased in the Q10 group (mean +/- SD: 0.9+/-0.2 vs. 2.0+/-1.0 microg/ml, P<0.005), with no change in the placebo group (0.9+/-0.3 vs. 0.9+/-0.3 microg/ml, not significant (NS)). Following intervention no differences existed between the Q10 and the placebo groups regarding HbA1c (7.86+/-0.88 vs. 7.84+/-0.84%), mean daily blood glucose concentrations (8.06+/-1.86 vs. 8.53+/-1.88 mM), mean insulin dose (52.1+/-13.2 vs. 52.6+/-21.4 U), hypoglycaemic episodes (2.0+/-1.8 vs. 2.5+/-2.1 episodes/week), or cholesterol concentrations (4.81+/-0.91 vs. 4.78+/-1.07 mM). Furthermore, no differences existed in the well-being of the patients reported from a visual analogue scale (physical: 0.67+/-0.21 vs. 0.71+/-0.18, psychological: 0.70+/-0.25 vs. 0.73+/-0.24).

CONCLUSION

Q10 treatment does not improve glycaemic control, nor does it reduce insulin requirement, and it can therefore be taken by patients with Type 1 DM without any obvious risk of hypoglycaemia. No major beneficial or unfavourable effects on the investigated parameters could be demonstrated and no major changes in the sense of well-being occurred in the patients.

[Primary pulmonary hypertension]

Primary pulmonary hypertension (PPH) is defined as continuing increase of the blood pressure in the pulmonary arteries without any known reason. The expected incidence in Western Europe is one to two per one million inhabitants, which in Denmark is around five to ten new cases each year. The diagnosis PPH is established by excluding other known reasons for secondary pulmonary hypertension. Primary pulmonary hypertension is a progressive and incurable disease. The treatment of PPH is with vasodilatory agents and anti-coagulants with supplementary diuretics, digoxin and oxygen as second-line of treatment. The most important vasodilators are calcium-antagonist and Epoprostenol (prostacyclin PGI2). Lung transplantation or combined heart and lung transplantation is at the moment the only possible treatment for progressive PPH disease in Denmark. The one year survival after lung- or heart and lung transplantation for PPH are not as good as the survival among other patients who are heart and lung transplanted.

The porcine bronchial artery: surgical and angiographic anatomy

The pig is often used in experimental studies on the significance of bronchial artery circulation, but the anatomy of this artery is only poorly described. The purpose of this study was to improve the anatomical basis for experimental studies on the porcine bronchial artery circulation. The origin of the artery from the aorta is described in 32 pigs. Heart-lung blocks were perfused with saline and removed in 16 pigs, and the broncho-oesophageal orifice was identified and cannulated. In these 16 specimens the intrapulmonary ramification was studied by angiography, and the extrapulmonary distribution and supply area by injection of Evans Blue. The broncho-oesophageal artery originated from the aorta as a single trunk in 91%. Angiography showed that each principal bronchus was accompanied by 2 bronchial artery branches far into the lung parenchyma. The central branching pattern of the artery between the aorta and the principal bronchi was divided into 3 subtypes. Evans Blue showed communication with the whole mediastinum. The anatomical relations are described. It is concluded that the broncho-oesophageal artery divides to follow each bronchus with 2 bronchial branches. A nomenclature for these branches is suggested. The pig anatomy is suited for experimental investigations on the bronchial circulation.

Airway epithelium of transplanted lungs with and without direct bronchial artery revascularization

OBJECTIVE

Normal systemic blood flow to the airways and lung parenchyma of transplanted lungs can only be re-established by direct bronchial artery revascularization. The purpose of the present study was to investigate whether such direct bronchial artery revascularization would preserve ciliary function, previously shown to be reduced in lungs transplanted without revascularization.

METHODS

Twenty-five single lung transplanted patients were included in this study. Complete direct bronchial artery revascularization was achieved in eight patients. In 16 patients the procedure had either failed (n = 10) or was not attempted (n = 6). In one patient the result of the revascularization was unknown. Airway epithelium samples were obtained from the native and the transplanted lungs during bronchoscopic examinations. Airway erythema and excessive secretion were registered. The epithelium samples underwent histological examination and ciliary beat frequency was measured in vitro by video recording. Transbronchial biopsies from the transplanted lungs were examined for signs of rejection and bronchitis.

RESULTS

No differences in ciliary beat frequency nor in the distribution of ciliated/de-ciliated columnar epithelium cells between native lungs and transplanted lungs with or without successful direct bronchial artery revascularization could be demonstrated. In 38% of the transplanted lungs without successful revascularization metaplastic or squamous epithelium was present, while lungs with successful revascularization had only normal columnar epithelium. Ongoing rejection or airway erythema did not influence ciliary beat frequency. Excessive secretion in the airways was the only finding associated with significantly increased ciliary beat frequency.

CONCLUSIONS

Ciliary beat frequency of epithelium cells of transplanted lungs did not differ from that of native lungs and consequently direct bronchial artery revascularization did not have any demonstrable important influence. Excessive secretion in the airways was associated with increased ciliary beat frequency. The histological findings also showed that the abundance of ciliated cells was preserved in transplanted bronchi irrespective of bronchial artery revascularization. However, epithelium metaplasia was only seen in transplanted bronchi without revascularization.

Role of cyclic nucleotide phosphodiesterases in resumption of meiosis

In the follicles of the mammalian and amphibian ovary, oocyte maturation is arrested at the prophase of the first meiotic division. Prior to ovulation, oocytes reenter the cell cycle, complete the meiotic division, and extrude the first polar body. Work from several laboratories including ours has provided evidence that the cAMP-mediated signal transduction pathway plays an important role in regulation of meiosis, the cyclic nucleotide acting as a negative regulator of maturation. Since cAMP can be regulated both at the level of synthesis and degradation, our laboratory is investigating the role of phosphodiesterases (PDE) in the control of cAMP levels of oocytes. Using pharmacological and molecular tools, we have determined that a PDE3 is the enzyme involved in the control of cAMP levels in the oocytes. In vitro and in vivo studies have established that inhibition of the oocyte PDE3 blocks resumption of a PDE is per se sufficient to cause resumption of meiosis in an amphibian oocyte model. The pathways regulating this PDE isoform expressed in the oocyte is under investigation, as they may uncover the physiological signals controlling meiosis.

The use of a stereological method to estimate the volume of Schistosoma mansoni granulomas: the effect of zinc deficiency

A quantitative, stereological method to assess the volume of Schistosoma mansoni granulomas is presented and its use demonstrated in a study of zinc-deficient animals. Twenty-six mice were divided into two groups, and given zinc-deficient or control food. After 4 weeks, the mean weight gain and thymus size were lower in the mice on the zinc-deficient diet. Eight mice in each group were then each infected with 60 S. mansoni cercariae and these mice were killed 12 weeks post-infection. There were then more eggs in the livers of the zinc-deficient mice than in those of the infected controls (7400/female worm v. 3300/female worm; P = 0.02), probably because of impaired intestinal egg expulsion and impaired resorption of eggs in the deficient mice. The median proportion of each liver occupied by granulomas was 0.11 among the zinc-deficient mice and 0.09 among the pair-fed, control mice (P = 0.08), and the median liver volumes were 1400 and 1450 microliters (P = 0.49), respectively. The computed median volume of all the granulomas in each liver was 160 microliters in zinc-deficient and 132 microliters in control mice (P = 0.32), while median granuloma volume per egg was 8.6 and 8.7 nl (P = 0.93), respectively. In contrast to conventional methods, modern stereological methods can provide estimates of granuloma volume or granuloma volume fractions without any assumptions about the size, shape, orientation or distribution of the granulomas in the liver.

Does bronchial artery revascularization influence results concerning bronchiolitis obliterans syndrome and/or obliterative bronchiolitis after lung transplantation?

OBJECTIVE

To study the frequency of histological obliterative bronchiolitis and clinical bronchiolitis obliterans syndrome after en bloc double lung transplantation with bronchial artery revascularization and bilateral lung transplantation without bronchial artery revascularization.

METHODS

Primary en bloc double lung transplantation with bronchial artery revascularization using the internal mammary artery as conduit was performed in 62 patients. The frequencies of obliterative bronchiolitis and bronchiolitis obliterans syndrome have been established from transbronchial biopsies and lung function measurements. Results have been analyzed in relation to the arteriographic success of bronchial artery revascularization and have been compared to results from Stanford University, obtained through personal communications.

RESULTS

Survival after 1, 2, 3, 4 and 5 years was 85, 81, 69, 69, and 69%, respectively. Fifteen patients developed bronchiolitis obliterans syndrome while seven developed obliterative bronchiolitis. Survival was superior for patients with bronchial artery revascularization classified as complete or incomplete bilateral versus incomplete hemilateral, incomplete poor or failed (P = 0.016, log-rank test). For patients surviving > or = 3 months post-transplant, the post-operative baseline FEV1 was lower for patients who later developed bronchiolitis obliterans syndrome compared to patients who did not (P = 0.007). The development of bronchiolitis obliterans syndrome and obliterative bronchiolitis were both correlated to observation time post-transplant but not to the number of rejections or infections when corrected for observation time.

CONCLUSIONS

In a subgroup of lung transplant patients, a process in the transplanted lungs, eventually leading to bronchiolitis obliterans syndrome diagnosis, seems to start in the donor during the transplantation and/or in the early post-operative cause. A comparison with results after bilateral lung transplantation without bronchial artery revascularization suggests that good direct bronchial artery revascularization may postpone the onset of bronchiolitis obliterans syndrome and obliterative bronchiolitis. The positive trend motivates further use of direct bronchial artery revascularization in lung transplantation.

Protein kinase B/Akt induces resumption of meiosis in Xenopus oocytes

The activation of protein kinase B/Akt is thought to be a critical step in the phosphoinositide 3-kinase pathway that regulates cell growth and differentiation. Because insulin-like growth factor 1 stimulates the resumption of meiosis in Xenopus laevis oocytes via phosphoinositide 3-kinase activation, we investigated the Akt involvement in this process. Injection of mRNA coding for a constitutively active Akt in Xenopus oocytes induced germinal vesicle breakdown (GVBD) to the same extent as progesterone or insulin treatment. Injection of mRNA coding for the wild type Akt kinase was less effective in stimulating GVBD, whereas Akt bearing a lysine mutation in the catalytic domain that abolishes the kinase activity had no effect. A mutant Akt lacking a membrane-targeting sequence did not induce GVBD, despite high levels of expression and activity. As previously reported for insulin, induction of GVBD by Akt was prevented by incubating the oocytes with cilostamide, an inhibitor specific for the type 3 phosphodiesterase (PDE3), suggesting that the activity of a PDE is required for Akt action. That an increase in PDE activity in the oocyte is sufficient to induce meiotic resumption was demonstrated by expression of an active PDE protein. In addition, the constitutively active Akt caused a 2-fold increase in the activity of the endogenous PDE. These data demonstrate that Akt is in the pathway controlling resumption of meiosis in the Xenopus oocyte and that regulation of the activity of a PDE3 is a step distal to the kinase activation.

Definition of MHC and T cell receptor contacts in the HLA-DR4restricted immunodominant epitope in type II collagen and characterization of collagen-induced arthritis in HLA-DR4 and human CD4 transgenic mice

Rheumatoid arthritis (RA) is an autoimmune disease associated with the HLA-DR4 and DR1 alleles. The target autoantigen(s) in RA is unknown, but type II collagen (CII) is a candidate, and the DR4- and DR1-restricted immunodominant T cell epitope in this protein corresponds to amino acids 261-273 (CII 261-273). We have defined MHC and T cell receptor contacts in CII 261-273 and provide strong evidence that this peptide corresponds to the peptide binding specificity previously found for RA-associated DR molecules. Moreover, we demonstrate that HLA-DR4 and human CD4 transgenic mice homozygous for the I-Abbeta0 mutation are highly susceptible to collagen-induced arthritis and describe the clinical course and histopathological changes in the affected joints.

Inducible nitric oxide synthase (iNOS) in the human heart: expression and localization in congestive heart failure

The inducible nitric oxide (NO) synthase (iNOS or NOS2) generates a prolonged release of large amounts of NO which may be cytotoxic and/or inhibit myocyte contractility. It has been suggested that this mechanism specifically contributes to heart failure caused by dilated cardiomyopathy (DCM). To test this hypothesis we compared the myocardial amount and localization of iNOS in myocardial biopsies from patients with heart failure caused by either DCM or ischemic heart disease (IHD). During heart transplantation, myocardial biopsies collected from the diseased heart after explantation were frozen in liquid nitrogen. Twenty-two patients in NYHA class III-IV were included (DCM: n = 8; IHD: n = 14). In each biopsy, iNOS expression was assessed using reverse transcription polymerase chain reaction (RT-PCR), and visualized by immunohistochemistry. iNOS was detected in all biopsies. Intriguingly, the amount of iNOS mRNA (shown as iNOS cDNA normalized to GADPH cDNA) did not differ significantly between the two groups (DCM 30 +/- 7; IHD 20 +/- 6, mean +/- S.E.M., P > 0.05). Similarly, no inter-group differences in the amount of iNOS protein (Western) were observed. iNOS was invariably located to vascular endothelial and smooth muscle cells. In addition, an iNOS reaction in relation to the myocyte membrane was found in 4 of the 22 patients. These four patients (two from each group) had significantly (P < 0.05) higher iNOS/GADPH ratios (54 +/- 20) than patients without myocyte membrane iNOS reaction (17 +/- 15). In conclusion, iNOS is expressed in the myocardium of all patients with heart failure caused by either DCM or IHD. iNOS is located primarily and invariably in the endothelium and vascular smooth muscle cells of the myocardial vasculature and its expression appears to be associated with the condition of heart failure per se rather than related to the heart failure etiology.

Expression of alpha and beta subunits of the integrin superfamily in articular cartilage from macroscopically normal and osteoarthritic human femoral heads

OBJECTIVE

The objective of this study was to detail the topographical and zonal distribution of alpha and beta subunits of the integrin superfamily in normal and osteoarthritic cartilage.

METHODS

Immunohistochemistry utilising antibodies towards alpha and beta subunits was performed on cryostat sections of human articular cartilage from macroscopically normal (n = 6) and osteoarthritic (n = 6) femoral heads. Samples of articular cartilage were obtained from 12 topographically distinct sites from each femoral head. Each section was divided into zones (superficial, middle, deep) and staining scores were recorded.

RESULTS

Normal cartilage stained for integrin subunits alpha 1, alpha 5, alpha V, beta 1, beta 4, and beta 5, but not for alpha 2, alpha 3, alpha 4, alpha 6, beta 2, beta 3, and beta 6. Intact and non-intact residual cartilage from osteoarthritic femoral heads stained for alpha 1, alpha 2, alpha 5, alpha V, beta 1, beta 4, and beta 5. Staining was occasionally seen for alpha 4 and beta 2, but not for alpha 3, alpha 6, beta 3, and beta 6. There was no topographical variation in the staining for any of the subunits in either normal or osteoarthritic cartilage. The only subunit that displayed a zonal variation was alpha V; staining for this subunit was most pronounced in the superficial zone compared with the middle and deep zones.

CONCLUSION

Chondrocytes in normal and osteoarthritic cartilage express the integrin subunits alpha 1, alpha 5, alpha V, beta 1, beta 4, and beta 5. Chondrocytes in osteoarthritic cartilage, in addition, express the alpha 2, alpha 4, and beta 2 subunits. The alpha v subunit is expressed by more chondrocytes in the superficial zone in comparison with cells in the deeper zones. None of the subunits display topographical variation in expression.

Immunohistochemical detection of DNA topoisomerase IIalpha, P-glycoprotein and multidrug resistance protein (MRP) in small-cell and non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC) differ significantly in their clinical response to topoisomerase IIalpha (topo-IIalpha)-directed drugs, such as etoposide and teniposide, as NSCLC is virtually insensitive to single-agent therapy, while SCLC responds in two-thirds of cases. Preclinical studies have indicated that resistance to topo-IIalpha drugs depends on topo-IIalpha content and/or activity, the altered-topo-II multidrug resistance phenotype (at-MDR) and/or one of two different drug efflux pumps, P-glycoprotein (P-gp) and the multidrug resistance protein (MRP). Immunohistochemical analysis on paraffin-embedded tissue from 27 cases of untreated NSCLC and 29 cases of untreated SCLC (of which additional tumour biopsies after treatment with topo-IIalpha-directed drugs were available in ten cases) yielded the following results: NSCLC had significantly less topo-IIalpha than SCLC (P < 0.0001), as only 5 out of 27 NSCLC cases had > 5% positive cells compared with 28 out of 29 SCLC, and 0 out of 27 NSCLC had > 25% positive cells compared with 26 out of 29 SCLC. P-gp was detected in > 5% of cells in only 3 out of 27 NSCLC and in 6 out of 29 SCLC, and MRP in 5 out of 27 of NSCLC and 9 out of 29 SCLC. After treatment of patients with SCLC with either etoposide or teniposide, which are topo-IIalpha-directed drugs, there was an increase in MRP (P < 0.1) and P-gp (P < 0.05) positivity, while topo-IIalpha decreased (P < 0.05). In conclusion, the major difference between untreated NSCLC and SCLC was in topo-IIalpha content. In the small series of ten patients treated for SCLC, all three MDR phenotypes appeared to increase.

CD44 expression is up-regulated in the deep zone of osteoarthritic cartilage from human femoral heads

AIMS

The objective of this study was to detail the topographical and zonal distribution of the cell adhesion molecule CD44 in normal and osteoarthritic cartilage.

METHODS AND RESULTS

Immunohistochemistry utilizing well characterized anti-CD44 antibodies (clones A3D8, Bric 235, 2C5) was performed on cryostat and paraffin sections of human articular cartilage from macroscopically normal (n = 18) and osteoarthritic (n = 11) femoral heads. Samples for cryostat sections were obtained from 12 topographically different sites. Sections were divided into zones (superficial, middle, deep) and the CD44 staining scored. Chondrocytes in normal articular cartilage and cartilage from osteoarthritic femoral heads stained positive for CD44 in both cryostat and paraffin sections. Normal cartilage showed a significant decrease in CD44 staining in the deep zone as compared to the superficial zone (P < 0.05). However, cryostat sections of residual cartilage from osteoarthritic femoral heads showed increased CD44 staining in the deep zone as compared to normal articular cartilage. The CD44 staining showed no topographical variation in either the normal cartilage or the osteoarthritic residual cartilage.

CONCLUSIONS

CD44 expression displays a distinct zonal variation in normal articular cartilage which is lost in osteoarthritic cartilage due to an up-regulated expression in the deep zone. CD44 expression does not exhibit topographical variation.

Dynamic autoregulation and renal injury in Dahl rats

The Dahl salt-sensitive (Dahl S) rat develops hypertension and renal injuries when challenged with a high salt diet and has been considered to be a model of chronic renal failure. Renal injuries appear very early in life compared with the spontaneously hypertensive rat (SHR). During the course of hypertension, a gradual impairment of autoregulatory control of renal blood flow might expose the glomerular circulation to periods of elevated pressure, resulting in renal injuries in Dahl S rats. Dynamic autoregulatory capacity was assessed in Dahl S and Dahl salt-resistant (Dahl R) rats, SHR, and Sprague-Dawley rats by inducing broad-band fluctuations in the arterial blood pressure and simultaneously measuring renal blood flow. Dynamic autoregulation was estimated by the transfer function using blood pressure as the input and renal blood flow as the output. Renal morphological injuries were evaluated in Dahl S rats and SHR and were scored semiquantitatively. Dynamic autoregulation was efficient and comparable in the low-frequency range (<0.015 Hz) in Dahl R rats, SHR, and Sprague-Dawley rats. The response in Dahl S rats depended strongly on the initiation time of the high salt diet. Autoregulation was preserved during a low salt diet and in rats exposed to a late-onset hypertension of short duration, only partly preserved if the late-onset hypertension was of a longer duration, and abolished in early-onset hypertension. All Dahl S rats on a high salt diet showed severe morphological changes in the kidney. In conclusion, autoregulatory capacity in the kidney of Dahl S rats is gradually impaired when rats are rendered hypertensive with a high salt diet. Renal morphological injuries develop before loss of dynamic autoregulation. Impaired autoregulation appears to be the result, not the cause, of the process that ultimately leads to renal failure in the Dahl S rat.

Histologic/histochemical grading system for osteoarthritic articular cartilage: reproducibility and validity

OBJECTIVE

To evaluate the reproducibility and validity of the histologic/histochemical grading system (HHGS) for osteoarthritis (OA) developed by Mankin and coworkers.

METHODS

Sections of human articular cartilage from macroscopically normal and osteoarthritic femoral heads were graded by the HHGS (0-14 scale) twice by 3 observers, and intra- and interobserver reproducibility was determined.

RESULTS

The exact intra- and interobserver reproducibilities ranged from 22% to 33% and from 13% to 25%, respectively. Intra- and interobserver variation ranged from -7 to 5. Although scores were generally higher in cartilage from osteoarthritic joints as compared with cartilage from normal joints, the difference reached statistical significance for only 2 observers. Additionally, the average scores from all observers were within the definitive range for OA (>5) in 30% of sections from normal joints, and in only 47% of sections from OA joints.

CONCLUSION

The results indicate that the reproducibility and the validity of the HHGS are inadequate, and an improved histopathologic grading system for OA is needed.

Medium-term patency and anatomic changes after direct bronchial artery revascularization in lung and heart-lung transplantation with the internal thoracic artery conduit

OBJECTIVE

Our purpose was to study the 2-year patency of direct bronchial artery revascularization in lung transplantation. We wanted to clarify whether the revascularized bronchial artery system is functional after 2 years, whether bronchial artery vascularity changes with time, and whether posttransplantation bronchial artery disease is arteriographically evident after 2 years.

METHODS

Bronchial artery revascularization is performed by anastomosing the internal thoracic artery to as many bronchial artery orifices in the donor descending aorta as possible. Twenty-three patients surviving 2 years or more have had internal thoracic artery-bronchial arteriography performed 1 month and 2 years after transplantation. One-month and 2-year arteriograms have been compared.

RESULTS

Two-year patency of the internal thoracic artery conduit was 100%. The appearance of the bronchial arteries was unchanged after 2 years in 11 patients. A unilateral or bilateral increase in vascularity was found in two and seven patients, respectively. In three patients new vessels, not visible on the first arteriogram, had appeared. In four patients one or more small vessels visible on the first arteriogram had disappeared on the second arteriogram. We have found no arteriographic signs of bronchial artery disease, such as stenosis of the bronchial arteries, and no arteriographic evidence of arteriosclerotic disease in the internal thoracic artery.

CONCLUSION

The internal thoracic artery is an excellent conduit for bronchial artery revascularization, with a 2-year patency of 100% in 23 patients. Only minor changes in the bronchial arteriograms have been found.

Modified cytokeratins expressed on the surface of carcinoma cells undergo endocytosis upon binding of human monoclonal antibody and its recombinant Fab fragment

Previously, we have reported on successful imaging of colon, rectal, and pancreatic carcinomas in patients by using a radiolabeled all-human monoclonal antibody, COU-1, directed against modified cytokeratin. To further develop this antibody for use as an immunoconjugate, COU-1 was cloned by phage display selection and the human Fab fragment was expressed in bacteria. Analysis by confocal laser scanning microscopy demonstrated that COU-1 bound in a uniform punctate pattern to the surface of viable carcinoma cells stained at 4 degrees C, and binding increased significantly when cells were cultured on fibronectin, laminin, or collagen IV. In the case of fibronectin, COU-1 staining was particularly enhanced at intercellular junctions. When carcinoma cells were cultured with COU-1 at 37 degrees C for 6 hr, the antibody was found in large perinuclear vesicles and the punctate surface staining was significantly reduced. Similar results were obtained using intact IgM COU-1 and the recombinant Fab fragment. Immunohistological studies indicated that COU-1, in contrast to murine monoclonal antibodies against normal cytokeratin 8 and 18, could differentiate between malignant and normal colon epithelia, and between colon cancer metastasis in the liver and surrounding normal hepatocytes. Within biopsies of malignant tissue, COU-1 exhibited membrane-associated staining of proliferating cells, while resting cells had a filamentous pattern. Thus, modified cytokeratin at the surface of carcinoma cells may represent a new target for immunoconjugates and may explain the promising results of the phase I/II clinical study.

[Clinical results after en block double lung transplantation with direct bronchial revascularization. The first three and a half years' experience in Denmark]

En-bloc double lung transplantation with tracheal anastomosis and direct revascularization of the bronchial arteries to the left internal mammary artery has been carried out in Denmark since June 1992. Forty-seven patients (32 with alfa-1 antitrypsin deficiency, 11 with chronic obstructive pulmonary disease, two with cystic fibrosis and two with primary pulmonary hypertension), 25 men and 22 women, average age 39 years (17-64 years), have received their first double-lung transplant with bronchial artery revascularization. Arteriography of the internal mammary artery and bronchial arteries was performed in 42 (89%) of the patients from 1-150 days after the operation. Successful bronchial artery revascularization was demonstrated arteriographically in 40 patients, in two patients the arteriography failed to show bronchial artery revascularization. Arteriography was not performed in five patients due to early complications and death. Bronchoscopy showed rapid, uncomplicated airway healing in 42 patients. Mucosal necrosis under the tracheal anastomosis was found in three patients, and severe obstructive endobronchial growth of the fungus Aspergillus fumigatus was diagnosed in the last two patients. The one- and two-year survival is 83% (Kaplan-Meier). Eleven patients are dead, five due to pulmonary causes and six due to extra-pulmonary causes. Pulmonary function became normal in nearly all surviving patients between three to six months after the transplantation. In conclusion, en-bloc double-lung transplantation with bronchial artery vascularization has shown good short-term results, and the one- and two-year survival gives hope that a successful bronchial artery revascularization will improve the long-term survival following lung transplantation.

Transitional cell carcinoma express vitamin D receptors

Recently, vitamin D analogues have shown antineoplastic effect in several diseases. Vitamin D analogues exert its effect by interacting with the vitamin D receptor (VDR). Studies of VDR in transitional cell carcinoma (TCC) have not been reported. The purpose of the present study was therefore to examine whether human bladder tumor cells express VDR. Tumor biopsies were obtained from 26 patients with TCC. Expression of VDR was examined by immunohistochemical experiments. All tumors expressed VDR. Biopsies from advanced disease contained more VDR positive cells than low stage disease (p < 0.05). Similarly, also tumor grade appeared to be related to the number of cells expressing the receptor. Normal urothlium also expressed VDR but only with low intensity. Our study shows that TCC cells possess the VDR receptor which may make them capable to respond to stimulation with vitamin D, but functional studies of vitamin D's effect on TCC cells in vitro are necessary before the efficacy of treatment with vitamin D analogues in TCC can be evaluated in patients.