A Clinical Trial on Weight Loss among Truck Drivers.

BACKGROUND: The high prevalence of obesity among commercial truck drivers may be related to sedentary nature of the job, lack of healthy eating choices, and lack of exercise. There may be a link between obesity and crash risk, therefore an intervention to reduce obesity in this population is needed. OBJECTIVE: To assess feasibility of a 12-week weight loss intervention for truck drivers with a weight loss goal of 10% of initial body weight. METHODS: Drivers were selected based on age (≥21 years) and body mass index (≥30 kg/m^2). The drivers participated in a before-after clinical trial. The intervention included a 12-week program that provided information on healthy diet and increasing exercise, and telephone-based coaching using SMART goals. Outcomes included change from baseline in reported energy intake, measured weight, waist, hip, and neck circumference, blood pressure, and point of care capillary blood lipids and hemoglobin A1c. Exit interviews were conducted to gain insight into driver opinions on the program features and usefulness. This study was registered with the NIH Clinical Trials Registry, number NCT02348983. RESULTS: 12 of 13 drivers completed the study. Weight loss was statistically significant (p=0.03). Reported energy (p=0.005), total fat consumption (p=0.04), and saturated fat consumption (p=0.02) intake were also lower after the 12-week intervention. Drivers attributed their weight loss to health coaching and suggested a longer intervention so that they could reach their goal and become accustomed to the changes. CONCLUSION: This weight loss intervention is feasible for this difficult population. Additional research is needed to compare this intervention with a control group.

Stable platinum isotope measurements in presolar nanodiamonds by TEAMS.

Nanodiamonds are stardust grains commonly found in primitive meteorites. They survived the formation of the solar system and kept their own individuality. Measurements of trace-element isotopic signatures in these grains will help understanding heavy element nucleosynthesis in massive stars and dust formation from their ejecta. We have continued previous attempts to search for stable Pt isotope anomalies in nanodiamonds via trace element accelerator mass spectrometry (TEAMS). The installation of a new injector beam line at the VERA facility allowed studying low traces of stable elements in different materials. Moreover, recent experiments showed that VERA provides the required measurement precision together with a low Pt machine background. Here, we observed for the first time an indication for enhancements of 198Pt/195Pt isotope ratios in two diamond residues prepared by different chemical separation techniques from the Allende meteorite. Variations in other isotopic ratios were within analytical uncertainty, and no anomaly was identified in a third diamond fraction.

[Neurotheology: neurobiological models of religious experience]. / Neurotheologie : Neurobiologische Modelle religiöser Erfahrungen.

Religions are evolutionary selected social and cultural phenomena. They represent today belief and normative systems on which the main parts of our culture are based. For a long time religions have been seen as mainly originating from a spectrum of religious experiences. These include a broad spectrum of experiences and are astonishingly widespread in the population. The most consistent and transculturally uniform religious experiences are the mystical experiences. Only these (and the prayer experience) have factually been researched in detail neurobiologically. This article presents a review of empirical results and hypothetical approaches to explain mystical religious experiences neurobiologically. Some of the explanatory hypotheses possess logical evidence, some are even supported by neurobiological studies, but all of them have their pitfalls and are at best partially consistent. One important insight from the evidence reviewed here is that there may be a whole array of different neurophysiological conditions which may result in the same core religious mystical experiences.

[Demands on dialysis access from the nephrologists point of view]. / Ansprüche des Nephrologen an den guten Dialysezugang.

Vascular access is the lifeline of hemodialysis patients. The superiority of autogenous arteriovenous fistulas compared to prostethic arteriovenous grafts or a central venous catheter is well established. Fistulas have a far lower risk of failure and a reduced requirement for revision compared to prosthetic grafts. Alternative vascular access can be achieved via a prosthetic graft or permanent central venous catheter but the risk of infection is increased. The most important complications are shunt thrombosis, stenosis, aneurysms or steal syndrome. Signs of these complications should be recognized by the dialysis team and early surgical intervention can avoid major complications. In many cases a complex shunt is necessary if the patient has been on dialysis for a long time. Interaction between the dialysis team, nephrologists, surgeons and interventional radiologists can improve the prognosis of dialysis patient.

General insufficiency of the classical CDC-based crossmatch to detect donor-specific anti-HLA antibodies leading to invalid results under recipients' medical treatment or underlying diseases.

Antibodies directed against HLA antigens of a given donor represent the most prominent cause for hyper-acute and acute rejections. In order to select recipients without donor-specific antibodies the complement-dependent cytotoxicity (CDC-) crossmatch as the standard procedure was established. As a functional assay it strongly depends on the availability of isolated donor lymphocytes and in particular on their vitality. However, due to several diseases or pharmacological treatment of a given recipient unexpected "false-positive" results of the CDC-crossmatch may arise. We here present three groups of patients which demonstrate the limits of the conventional crossmatch. 1) Kidney recipients before living donations exhibited positive CDC-reactions due to their conditioning using the therapeutical anti-CD20 mAb Rituximab (n=7), routinely used to deplete B-cells, or the anti-CD25 mAb basiliximab (n=2) to inhibit the proliferation of activated T-cells. 2) Recipients suffering from various leukaemias (n=5) exhibited "positive" CDC-crossmatches using PBL of the donors, although formerly these patients had never shown anti-HLA antibodies. Instead of donor-specific allo-antibodies, cytostatic agents such as 6-mercaptopurine led to an unspecific cell death. 3) Patients projected for post mortem or living kidney donations (n=44) exhibited "positive" CDC-crossmatch results which were not in accordance with their former antibody status and, partially, with high degrees of HLA-matching. These implausible results were due to underlying auto-immune diseases, mainly of the systemic immune complex type III such as lupus erythematosus, mainly leading to false-positive B-cell crossmatches by immune complexes binding to Fcγ-receptors. In all these 58 cases the alternatively performed ELISA-based "Antibody Monitoring System" (AMS-) crossmatch assay was not artifically affected, suggesting that this assay may be comprehensively established at least for the cases described.

Presence of cardiovascular disease in patients on a waiting list for renal transplantation and in patients after kidney transplantation in a single center.

BACKGROUND: Cardiovascular risk in hemodialysis patients is enhanced, resulting in a higher mortality rate compared with the general population, yet the average wait time for renal transplantation in Germany is 5-7 years. The age of wait-listed patients has risen progressively. The aim of this study was to evaluate the prevalence of cardiovascular disease in patients on the waiting list in our center before and after renal transplantation as well as the extent to which invasive treatment was required in these patients. METHODS: The study investigated 2 groups: 350 patients on the renal transplantation waiting list at our center in 2008 and 324 patients who underwent renal transplantation at the same center in the years 2003-2007. RESULTS: In 2008, 141 women and 209 men with a mean age of 48.6 years (range 13-71 years) were on the waiting list. In the years 2003-2007, 98 women and 226 men with a mean age of 54.3 years (range 16-78 years) received renal transplants. One hundred six patients on the waiting list for renal transplantation had to undergo coronary angiography. There is no upper age limit for donors or recipients in our program. Mean age at admission on the waiting list was 48.6 years (range 13-71 years). Mean age at transplantation was 54.3 years (range 16-78 years) in our center. Most of these patients were asymptomatic but presented a risk profile that included diabetes mellitus, severe general atherosclerosis, a pathologic ergometric test, or abnormal myocardial scintigraphy. Only in 1 case could coronary heart disease be excluded. Seventy patients (20%) suffered from mild to moderate coronary heart disease without the need for intervention. In 5 patients (1.4%) coronary bypass surgery was necessary due to severe 3-vessel coronary heart disease. In 2 cases (0.6%) replacement of the aortic valve was performed because of aortic valvular stenosis. Coronary angioplasty without implantation of stents was done in 2 patients (0.6%). Twenty-two patients (6.8%) were treated with implantation of bare metal stents and 6 patients (1.7%) with drug-eluting stents. After renal transplantation, 22 patients (6.8%) suffered from peripheral arterial occlusive disease. In 58 patients, coronary heart disease was documented by angiography. 16 patients (4.9%) had 1-vessel disease, 23 patients (7%) 2-vessel disease, and 19 patients (5.8%) 3-vessel disease. Myocardial infarction was documented in 18 patients (5.5%) before and in 5 patients (1.5%) after renal transplantation. Bare metal stent implantation was performed in 6 patients (1.8%) after transplantation. One patient received a drug-eluting stent after renal transplantation. In the years 2003-2007, 22 patients underwent coronary bypass surgery before kidney transplantation. CONCLUSION: The prevalence of coronary heart disease is high in patients on the waiting list and after renal transplantation. The majority of these patients are clinically asymptomatic. One-third of the patients with coronary heart disease had to be treated invasively. Nevertheless, many diabetic patients are very sick from multiple complications after the waiting time, making theme unsuitable for transplantation.

[Sexuality after kidney transplantation]. / Sexualität nach Nierentransplantation.

The quality of life of patients after kidney transplantation is of increasing interest. In this connection, issues of sexuality are meaningful too. Many patients with end-stage kidney disease suffer from sexual disorders. More than 50% of the male patients on dialysis and even more females are affected by disturbances such as erectile dysfunction and loss of libido or abnormal menstrual cycles. After successful kidney transplantation most symptoms in women are improved, whereas in men disturbances in erectile function often persist or even deteriorate. In these patients treatment with inhibitors of phosphodiesterase type 5 is a valid option with an effective response. In women with stable graft function pregnancy can be achieved successfully. Nevertheless, pregnant kidney allograft recipients should be considered as high-risk patients needing special care under the supervision of a team of obstetricians and nephrologists.

Evolution of light chain deposition disease over 8 years.

A 44-year-old female was diagnosed with proteinuria due to nodular glomerulosclerosis secondary to light chain deposition disease (LCDD). After 6 years, deterioration of kidney function occurred and autologous stem cell transplantation was considered, but the patient refused specific therapies. The disease progressed slowly, over a period of 8 years reaching now chronic renal insufficiency stage 4 with a creatinine clearance of 20 ml/min, in spite of no specific therapy. This case, documented by repeated biopsies, demonstrates the very slow loss of kidney function, suggesting the possibility of conservative treatment strategies without taking the risks of chemotherapy or autologous stem cell transplantation, since no long term follow up data of these therapies are available for LCDD.

Impact of immunologic and nonimmunologic variables on long-term outcome after kidney transplantation.

OBJECTIVE: To assess the effect of longer cold ischemia time and other parameters on outcomes after kidney transplantation, where both organs were taken from the same donor and transplanted in the same clinic. METHODS: Retrospective analysis of renal transplants at our center. RESULTS: From December 1990 to June 2006, we identified 166 transplant patients who received one organ from a pair. Median donor age was 52.4 years, median follow-up of recipients was 56 months (range = 0-156). Cold ischemia time of the group who underwent first transplantation (receiving the first kidney of a pair from one donor, designated group 1) was 644 minutes; for the second transplantation (group 2), 917 minutes (P < .0001). No difference was observed in warm ischemia times (40.8 +/- 12.9 vs 42.5 +/- 12.7 minutes, P = .4) or number of mismatches (MM; 3.4 vs 3.5, P = .7). The 5-year graft survival of the whole group was 66% with a death-censored value of 75%. Group 1 patients tended to show better primary graft function rates (80% vs 72%; P = .1). No significant differences were observed in 1-year graft survival rates for the two groups (81% vs 78%, P = .7) or in long-term graft survival (log-rank: P = .7). There was no influence of the number of MM on delayed graft function rates, but it was significant for long-term graft survival (log-rank: P [uncensored for death] = .023 for 0-3 MM vs 4-6 MM). CONCLUSIONS: Nonimmunologic parameters have less influence on the outcome of kidney transplantation than immunologic factors.

Anemia after renal transplantation: an underestimated problem.

In end-stage renal disease patients anemia is known to be an independent risk factor for cardiovascular disease and death. In a monocenter retrospective analysis, we investigated 207 stable patients (68 women/139 men) who underwent a first renal transplantation. Immunosuppressive therapy was performed with either cyclosporine plus mycophenolate mofetil, tacrolimus plus mycophenolate mofetil, or rapamycin plus mycophenolate mofetil; 43.5% of the patients were treated with steroids. Seventy-eight patients (37.7%) displayed anemia, including 8.7% with a severe disorder displaying an average hemoglobin (Hb) level of <6.8 mmo/L in men and <6.2 mmol/L in women. In 8.2% of the cases, we observed moderate anemia (Hb 6.8-7.4 mmol/L in men and 6.2-6.8 mmol/L in women), and in 20.8% (29 men and 14 women), mild anemia (Hb <8.06 mmol/L in men and <7.45 mmol/L in women). Erythropoietin was administered in 55.5% of patients with severe anemia, 53% with moderate anemia, and 11.6% with mild anemia. Serum creatinine level was a significant predictor of anemia (B -0.004; SE 0.001; P < .01). Among patients with creatinine >200 micromol/L, 63% were anemic compared with 22% of those with a serum creatinine level <200 micromol/L (P < .05). No correlation was observed with immunosuppressive medication or treatment with angiotensin-converting enzyme inhibitors/angiotensin-II receptor antagonists. During a 3-year follow-up, both mortality and graft failure rates were significantly greater among anemic patients nonanemic patients (mortality 3.3% vs 0.5%, P < .001; graft failure 4.3% vs 0%, P < .001). We found an unexpectedly high incidence of anemia in patients with well-functioning grafts. Anemia as a risk factor for mortality and graft failure should be treated more intensively among renal transplant patients.

Bone histomorphometry and biochemical markers of bone turnover in patients with chronic kidney disease Stages 3 - 5.

AIMS: Precise identification of renal osteodystrophy requires bone histomorphometry. Several markers of bone turnover may be useful to predict classification and severity of renal osteodystrophy, but there are only limited data whether these markers correlate with bone histomorphometry. METHODS: In 36 patients with chronic kidney disease (CKD) Stage 3/4 and in 96 patients with CKD Stage 5 bone histomorphometry was performed and renal osteodystrophy was classified according to the standardized international nomenclature. Blood samples were taken at the time of bone biopsy, stored and analyzed at the end of the study. RESULTS: Osteitis fibrosa (OF) was the most frequent histomorphometric form, occurred in 47.2% in CKD Stages 3 - 4 and in 61.4% in CKD Stage 5. There was no difference in the frequency of adynamic renal bone disease (ARBD). The correlation coefficients between bone turnover markers and histomorphometric parameters were higher in CKD 5 patients with high bone turnover lesions. The predictive value for high versus low/normal bone turnover status was comparable for alkaline phosphatase (APH), bone alkaline phosphatase (BAP), pyridinoline (Pyd), desoxypyridinoline (Dpyd), tartrat-resistent acid phosphatase (TRAP Vb) and parathyroid hormone (PTH) in CKD Stage 5 patients, but was insufficient for APH and TRAP Vb in CKD Stage 3 - 4 patients. CONCLUSIONS: Besides parathyroid hormone, biochemical parameters of bone turnover provide a moderate discrimination and prediction of bone turnover status only in patients with CKD Stage 5. Due to a large variability, they are of limited use in predicting the histomorphometric type of renal osteodystrophy. Bone histology remains necessary for an exact classification of underlying pathology.

Renal retransplantation: a retrospective monocentric study.

Approximately 10% to 20% of all annual renal transplantations are retransplantations and up to 20% of patients on waiting lists need a repeat kidney because of previous graft failure. The immunological risk is much greater among retransplanted patients than first-time kidney recipients. It is likely that retransplantation will become even more prevalent in the future. However, clinical studies or retrospective data are rare in this patient population. We retrospectively investigated 50 recipients after second or third renal transplantations in our center since 2001. Immunosuppression was performed with corticosteroids, mycophenolate mofetil (MMF), tacrolimus, and induction therapy with either thymoglobulin (2.5 mg/kg body weight; n = 27) or 20 mg basiliximab on days 0 and 4 (n = 22) after renal transplantation; 1 patient was treated with antithymoglobulin Fresenius after combined liver-kidney transplantation. Acute rejection occurred in 12 recipients (44.4%) after thymoglobulin and in 7 recipients (31.8%) after basiliximab induction therapy (P < .05). In 4 (14.8%) thymoglobulin- and 5 (22.7%) basiliximab-treated recipients, vascular rejections were observed (P = NS). Patients with basiliximab treatment showed improved renal function at 1 year after transplantation: serum creatinine 134.3 mumol/L versus 199.6 mumol/L in the thymoglobulin group (P < .05). Over the observation period the renal function remained stable or improved in both groups if rejection treatment was successful. However, allograft failure was higher in the basiliximab-treated group, namely, 18.1% versus 14.8% in thymoglobulin-treated patients, but the difference did not reach statistical significance. In 3 (11.1%) thymoglobulin- and 4 (18.2%) basiliximab-treated patients cytomegalovirus (CMV) infections complicated the follow-up (P = NS). In the follow-up period of 5 years, no malignant diseases were seen in either group. Three basiliximab-treated recipients died in the first year due to sepsis or cardiovascular complications. Two thymoglobulin-treated patients developed BK virus nephropathy in the follow-up period. In conclusion, we observed a high immunological risk and rejection risk among retransplanted kidney recipients in our center. Particularly, severe vascular rejections with a harmful long-term impact on allograft function were observed in this population. Induction treatment seems to be successful to reduce risk and achieve better results. Single-shot thymoglobulin may be preferable to reduce severe vascular rejection and prevent allograft failure than basiliximab with the same infection rate.

A single-center experience with BK virus nephropathy.

BACKGROUND: BK virus nephropathy has an increasing role in renal transplant dysfunction, since new, highly potent immunosuppressive drugs have been introduced into therapy following renal transplantation. Diagnosis of acute impairment of renal transplant function is complicated by difficulty in differentiating BK virus nephropathy from acute rejection. PATIENTS AND METHODS: We retrospectively described the findings and therapeutic approaches of 6 consecutive patients with BK virus nephropathy in our transplantation center (75 - 80 transplantations/ year). BK virus nephropathy was classified according to Drachenberg et al. [2004]. RESULTS: We observed an incidence rate of < 1% for BK nephropathy in our center. Four patients had a pattern B whereas 2 patients revealed a pattern C of BK virus nephropathy. Focal C4d-positive staining of peritubular capillaries were found in 2 of the 6 cases. For earlier detection of BK nephropathy, a diagnostic algorithm for each patient after renal transplantation was established. Urine was continuously monitored by cytology for decoy cells and PCR for BK virus DNA. If PCR was also positive for the BK virus in plasma, biopsy of the renal allograft was performed. Thereby diagnosis could be confirmed sooner. For treatment of BK nephropathy in our center, we reduced immunosuppressive agents and initiated a virustatic treatment with cidofovir in the first 3 cases. However, results were not satisfactory and two allografts were lost. We then reconsidered our therapeutic approach and switched the immunosuppressive treatment to leflunomide with consistent low dose steroids. We use therapeutic drug monitoring for leflunomide and aim at a target level of 40 - 100 microg/ml. We lost no allograft with BK nephropathy since using this therapeutic approach. CONCLUSION: In our center, leflunomide therapy, but not cidofovir, was effective in patients with BK virus nephropathy of the renal allograft.

Renal osteodystrophy after successful renal transplantation: a histomorphometric analysis in 57 patients.

Renal transplantation is the treatment of choice for patients with end-stage renal disease. It corrects most of the metabolic abnormalities that cause renal osteodystrophy. Nevertheless, renal osteodystrophy persists in many transplant recipients. The aim of this study was to investigate frequency and histomorphometric pattern of bone disease after renal transplantation. Bone biopsy specimens were taken from the iliac crest of 57 patients, including 28 women (26-70 years old) and 29 men (27-67 years old). Indications for biopsy were hypercalcemia, elevation of parathyroid hormone, and, in 19 cases, without suspected bone abnormalities based on laboratory parameters. The mean time of dialysis prior to renal transplantation was 43 months (range, 6-91 months in women and 10-111 months in men) and the mean interval between transplantation and bone biopsy was 53.5 months (range, 4-191 months in women and 5-90 months in men). Fourteen patients were treated with either 25-hydroxyvitamin D3 and/or 1-alpha hydroxyvitamin D3 or 1,25 dihydroxyvitamin D3, 3 with phosphate-binding agents. The immunosuppression consisted of cyclosporine, azathioprine, and prednisolone. The cumulative dosage of corticosteroids was 5569+/-5305 mg. For static and dynamic histomorphometry, we used American Society of Bone and Mineral Research nomenclature. Mild osteitis fibrosa and osteitis fibrosa, the most frequent forms of renal osteodystrophy, were observed in 13. (22.8%) and 14 patients (24.6%), respectively. Mixed uremic osteodystrophy was found in 7 patients (12.3%), adynamic renal bone disease in 3 patients (5.3%), and osteomalacia in 2 patients (3.5%). In 13 patients (22.8%), reduced bone mass and structural damage without typical signs of renal osteodystrophy, such as endosteal fibrosis or osteoclasia, were detected, and 5 patients (8.7%) showed normal histomorphometric parameters. We concluded that renal osteodystrophy, especially forms with high bone turnover, persisted in many patients after successful renal transplantation. This finding may be due to preexisting conditions, such as duration of dialysis and degree of hyperparathyroidism. Bone disease is increased by corticosteroid and immunosuppressive therapy after renal transplantation and requires close monitoring.

DNA fragmentation in acute and chronic rejection after renal transplantation.

Acute and chronic rejections are important denominators for the long-term function of renal grafts. One important indicator of cell damage is enzymatic DNA fragmentation. To investigate possible mechanisms, the rate of DNA fragmentation (TUNEL staining), the expression of tissue transglutaminase II (a marker of advanced DNA damage), and 8-hydroxy-2'-deoxyguanosine (8-OhdG), an indicator of oxidative injury of nucleic acids, were studied by immunohistochemistry. Semithin sections of renal biopsies revealed 23 patients to show acute interstitial rejections (Banff 97 IA, IB); eight patients, acute vascular rejection (Banff 97 IIA, IIB); and 20 patients, chronic allograft nephropathy (Banff 97 I to III). Correlations were calculated between apoptotic cells and serum creatinine at the time of biopsy and after 6 months. In acute rejection, the proximal tubular cells were apoptotic, particularly in regions with mononuclear infiltrates. In consecutive sections, these apoptotic tubular cells also showed damage by reactive oxygen species (positive 8-OhdG staining). Patients with acute interstitial rejection revealed the highest number of tubular DNA fragmentation (14.9 +/- 10.3) versus chronic allograft nephropathy (9.2 +/- 5.6) as TUNEL-positive cells per 80,000 micro m(2) (P < .05). Patients with acute vascular rejection showed a low degree of tubular apoptosis (6.8 +/- 5.1). There was no significant difference in glomerular DNA fragmentation between acute interstitial and chronic rejections: acute interstitial rejection = 7.1 +/- 5.9 versus chronic allograft nephropathy=6.1 +/- 3.9 TUNEL-positive cells per 80,000 micro m(2). There was a significant negative correlation between the degree of tubular (P < .01) and glomerular (P < .05) apoptosis and the serum creatinine at the time of biopsy as well as after 6 months in all patients irrespective of the Banff class. However, there was heterogeneity in the correlation between renal function and the degree of apoptosis in the glomerular and tubular compartments in the various Banff classes. A positive correlation (P < .01) was observed between the degree of tubular apoptosis and serum creatinine at 6 months after biopsy among patients with acute vascular rejection (Banff 97 IIA, IIB). The present data revealed a high degree of tubular DNA fragmentation associated with oxidative stress in acute interstitial rejection. Nevertheless, apoptosis did not generally negatively influence future renal function and may be important to clear proliferating cells. Apoptosis may also play a different pathophysiological role depending on the type of rejection.

CYP3A5 genotype markedly influences the pharmacokinetics of tacrolimus and sirolimus in kidney transplant recipients.

It is currently not clear whether the concentration-time curves of the immunosuppressants differ with respect to the CYP3A5, MDR1, or MRP2 genotype in dose-adapted stable kidney transplant patients. Dose/trough concentration ratios were obtained in 134 tacrolimus and 20 sirolimus-treated patients, and plasma concentration-time profiles were obtained from 16 (tacrolimus) and 10 (sirolimus) patients. Genotyping was carried out for CYP3A5 6986A>G; ABCB1 2677G>T/A, 3435C>T and ABCC2 -24C>T; 1249G>A; 3972C>T. Dose/trough concentration ratios were 0.67+/-0.3 and 1.36+/-0.73 x 10(3) l (P<0.00001) for tacrolimus and 0.42+/-0.17 and 0.84+/-0.46 x 10(3) l (P=0.18) for sirolimus in CYP3A5 non-expressors and expressors. The unadjusted tacrolimus area under curve (AUC)(0-12) was 106.8+/-17.5 ng/ml x h compared with 133.3+/-42.2 ng/ml x h (P=0.37) without affecting serum creatinine. Mean unadjusted AUC(0-24) of sirolimus did not differ significantly either. Therefore, CYP3A5 expressor status and not transporter variants is a main determinant of oral clearance, particularly for tacrolimus. Dose adaptation according to trough levels, however, appears to be sufficient to maintain similar concentration-time profiles.

DNA fragmentation in chronic glomerulonephritis: an immunohistological analysis.

BACKGROUND: Experimental data suggest that apoptosis plays an important pathophysiological role in glomerulonephritis by restoring tissue structure after proliferation of intrinsic renal cells and infiltration of leukocytes. Relatively little is known of apoptosis in human glomerulonephritis, particularly in predicting renal function during follow-up. METHODS: In order to colocalize different markers for cell damage in renal tissue from patients with different forms of glomerulonephritis (GN), a series of semithin sections from 34 kidney biopsies were studied retrospectively. Normal kidney from a nephrectomy specimen with a small renal adenocarcinoma served as a control. DNA fragmentation, expression of tissue transglutaminase II, BAX and BCL-2 were visualized immunohistochemically. In some renal biopsies, immunohistochemical staining for activated caspase 3 was performed. Proinflammatory markers (C-reactive protein, leukocytes), serum creatinine, creatinine clearance, total proteinuria, albuminuria, alpha(1)-microglobulin and IgG excretion were determined at the time of biopsy. Serum creatinine and total proteinuria were assessed 6 and 12 months after renal biopsy. RESULTS: Nuclei with different degrees of DNA fragmentation were mainly found in epithelial cells of tubules, but also in glomerular cells, regardless of the form of GN studied. Transglutaminase II expression was found only in cells with a strong staining for DNA fragmentation. DNA fragmentation localized to glomerular cells was more pronounced in proliferative than in non-proliferative forms of GN, being most abundant in patients with rapid progressive GN. Staining for activated caspase 3 in selected biopsies confirmed the presence of apoptosis. BAX and BCL-2 staining was detected within the same cells, but exhibited a different intracellular distribution. In proliferative GN, the extent of DNA damage in tubular epithelial cells significantly corresponds with the concentration of serum creatinine (p < 0.04) and with urinary excretion of alpha(1)-microglobulin (p < 0.01) at the time of biopsy. A significant correlation (p < 0.01) was seen between glomerular DNA fragmentation and follow-up total proteinuria 12 months after biopsy for proliferative forms of GN. The damaged glomerular area (e.g. mesangial sclerosis) significantly correlated with DNA fragmentation in proliferative, but not in nonproliferative GN at the time of biopsy. Furthermore, glomerular damaged showed a significant correlation with tubular DNA damage in proliferative GN. CONCLUSION: In glomerular cells, apoptosis may be important for the clearance of proliferating cells whereas in tubules, cell damage showed dependence on the degree of tubular injury mediated by inflammation and/or proteinuria. Although the degree of apoptosis in tubular cells correlates with serum creatinine in proliferative GN at the time of biopsy, it is of limited use to predict future renal function.