Factors Associated With Persistent Post-transplant Hyperparathyroidism After Index Renal Transplantation

INTRODUCTION

Secondary hyperparathyroidism (SHP) is common in end-stage renal disease and may progress to persistent post-transplant hyperparathyroidism (PTHP) following renal transplantation (RT). We sought to describe the frequency and determine factors associated with the incidence of PTHP for patients undergoing RT at a single institution that restricts RT for patients with uncontrolled SHP with a parathyroid hormone (PTH) of >800pg/mL at time of initial transplant evaluation.

METHODS

We conducted a single-institution retrospective study of adults undergoing index RT from 2012 to 2020 who had a calcium and PTH level within 12 mo prior to RT and at least 6 mo following RT. PTHP was defined as calcium of >10 mg/dL with an elevated PTH > 88pg/mL at six or more months following RT. Univariate analysis and multivariable logistic regression were performed for factors associated with developing PTHP.

RESULTS

We identified 1110 patients with RT, 65 were excluded for prior RT, 549 did not have a pre-RT and post-RT calcium, and PTH laboratories for inclusion, yielding 496 for analysis. Following RT, 39 patients (7.9%) developed PTHP, compared to those who did not develop PTHP; these patients had significantly higher pre-RT PTH, pre-RT calcium, and frequency of calcimimetic therapy. In multivariable logistic regression factors significantly associated with PTHP were pre-RT calcium of more than 10 mg/dL with an odds ratio (OR) of 3.57 (95% confidence interval [CI] 1.52-8.39, P = 0.003) and pre-RT calcimimetic therapy with an OR 1.30 (95% CI 1.06-2.85, P = 0.041). Compared with patients who had a pre-RT PTH of less than 200 pg/mL, a PTH of 200-399 pg/mL increased risk of PTHP with an OR of 4.52 (95% CI 1.95-21.5, P = 0.048) and a PTH of > 400 pg/mL increased risk of PTHP with an OR of 7.17 (95% CI 1.47-34.9, P = 0.015). In this cohort, 11 patients (28.2%) with PTHP underwent parathyroidectomy (PTx) at a mean of 1.4 y post-RT (standard deviation 0.87).

CONCLUSIONS

For patients required to have a PTH < 800pg/mL for initial transplant candidacy, the subsequent incidence of PTHP is relatively low at 7.9%. Risk factors for PTHP include higher pre-RT calcium and PTH levels and pre-RT calcimimetic therapy. PTx remains underused in the treatment of PTHP. Further study is warranted to determine the optimal PTH cutoff for transplant candidacy and recommendation for PTx in patients requiring calcimimetic therapy for SHP.

Effect of Arthrospira powders from different producers on the formation of endothelial cell monolayers

Arthrospira platensis (AP) and some of its derived products have well-established biological activities as antioxidants or as agents to reduce cardiovascular disease risk factors. Furthermore, AP products have gained increasing importance as potential anti-cancer agents. However, the ingredients of the available products vary greatly with the origin, the type of production and processing, which could have significant consequences for their biological effects. Therefore, the composition and biological influence of five distinct AP powders, which were acquired commercially or produced at a public biotechnology institute, were investigated in regard to their endothelialization capacity using a cell impedance- (CI) based measurement method. The study revealed that the AP composition and especially the influence on HUVEC proliferation differed significantly between the five AP powders up to 109%.Thus, it could be shown that the method used allows the reliable detection of quantitative differences in biological effects of different AP preparations.

Public health service increased risk donor kidney grafts for transplant into children, a survey of pediatric nephrologists

BACKGROUND

Kidney transplant is the best treatment for end-stage renal disease (ESRD); however, access is limited by severe organ shortage. Public Health Service increased risk donors (PHS-IRD) represent a significant portion of available organs which are discarded at disproportional rates.

METHODS

Pediatric nephrologists were surveyed regarding PHS-IRD kidneys to understand attitudes and perceived barriers to the use of these grafts in children. We sought to elucidate what methods may help increase the likelihood of PHS-IRD acceptance.

RESULTS

Twenty-two responses were received from United States pediatric nephrologists representing 11 UNOS regions (response rate 5.9%). Of respondents, 50% had been practicing for 20+ years, 77% in academic hospitals, and 63% in cities with over 1 000 000 people. All respondents worked in an institution with a kidney transplant program. 41% reported that they would not accept PHS-IRD kidneys under any circumstance, 45% would accept depending on the candidate's medical status, and 14% routinely accepted PHS-IRD kidneys. Infectious transmission was the biggest disincentive reported (59%), with only 55% of respondents feeling comfortable counseling families on the associated risks. 82% of respondents did not perceive all PHS-IRD as the same, and 90% supported stratifying PHS-IRD into tiers based on risk, which would increase the likelihood of organ acceptance (82%) and assist in counseling families (91%).

CONCLUSIONS

With improved utilization, PHS-IRD kidneys offer a step toward decreasing the organ shortage. These findings suggest hesitance in use of PHS-IRD kidneys for pediatric recipients. Further stratification of risk could aid in provider organ acceptance and counseling patients.

A multi-center study on safety and efficacy of immune checkpoint inhibitors in cancer patients with kidney transplant

Immune checkpoint inhibitors (ICIs) are widely used for various malignancies. However, their safety and efficacy in patients with a kidney transplant have not been defined. To delineate this, we conducted a multicenter retrospective study of 69 patients with a kidney transplant receiving ICIs between January 2010 and May 2020. For safety, we assessed the incidence, timing, and risk factors of acute graft rejection. For efficacy, objective response rate and overall survival were assessed in cutaneous squamous cell carcinoma and melanoma, the most common cancers in our cohort, and compared with stage-matched 23 patients with squamous cell carcinoma and 14 with melanoma with a kidney transplant not receiving ICIs. Following ICI treatment, 29 out of 69 (42%) patients developed acute rejection, 19 of whom lost their allograft, compared with an acute rejection rate of 5.4% in the non-ICI cohort. Median time from ICI initiation to rejection was 24 days. Factors associated with a lower risk of rejection were mTOR inhibitor use (odds ratio 0.26; 95% confidence interval, 0.09-0.72) and triple-agent immunosuppression (0.67, 0.48-0.92). The objective response ratio was 36.4% and 40% in the squamous cell carcinoma and melanoma subgroups, respectively. In the squamous cell carcinoma subgroup, overall survival was significantly longer in patients treated with ICIs (median overall survival 19.8 months vs. 10.6 months), whereas in the melanoma subgroup, overall survival did not differ between groups. Thus, ICIs were associated with a high risk of rejection in patients with kidney transplants but may lead to improved cancer outcomes. Prospective studies are needed to determine optimal immunosuppression strategies to improve patient outcomes.

Liposuction used to treat deep vascular accesses for hemodialysis

BACKGROUND

Oftentimes, obese dialysis patients develop a viable dialysis access but the access is too deep for cannulation and needs a superficialization procedure.

METHODS

We present our 14-patient cohort in whom we performed liposuction to superficialize viable but deep vascular accesses. Out of 14 patients, 12 had arteriovenous fistulas and 2 arteriovenous grafts. The primary end points were the ability to superficialize a completely unusable access and to remove the hemodialysis catheter (3patients), or to significantly extend the useful length of a deep access in which only a very short segment was used and to continue to use the access post-surgery without the need to place a dialysis catheter (11 patients).

RESULTS

The study goal was met in 13 out of 14 patients. In two of three patients, the catheters were removed and their access usable length was 14 and 13 cm, respectively. The accesses could be used immediately after liposuction in all patients in which this applied-11 patients. The usable access length increased from a mean of 5 to 12.7 cm. The access mean depth decreased from 10.8 mm pre-surgery to 7 mm post-surgery and 5.3 mm 4 weeks after surgery. The mean volume of fat removed was 43.8 cc. We had only one surgical complication: bleeding that was readily controlled with manual pressure. All patients were discharged to home the same day. Postoperative pain was mild.

CONCLUSION

Liposuction is effective, safe, and seems to be the least invasive technique of superficialization.

4964Loss-of-spen disturbs cardiac conduction in zebrafish mediated by impaired connexin43 function

Introduction

Genome-wide association studies identified SPLIT ENDS (SPEN) gene as an interesting candidate in the pathogenesis of heart failure. SPEN is known to be of importance in transcriptional regulation in several pathways and knockout in mice results in severe cardiac structural abnormalities and premature intrauterine lethality. Moreover, SPEN was associated with human 1.36 syndrome and is located in the critical region for congenital heart defects. Hence, spen seems to be of importance in cardiac physiology, but not much is known about its biologic function in the heart.

Purpose

The aim of our study was to further deepen the insights on spen's role in cardiac pathology.

Methods

Morpholino-mediated gene knockdown is an excellent method to approach in vivo function of cardiac candidate genes in zebrafish. We conducted spen-specific knockdown experiments and first analyzed the emerging heart failure and arrhythmia phenotype. Next, we assessed possible target genes of the transcriptional regulator spen by gene expression profiling and verified our results by quantitative real-time PCR (qPCR), Western Blot, in situ hybridization and further knockdown- and rescue-experiments.

Results

Spen-deficiency results in severe heart failure and arrhythmia in zebrafish. While in the first 24 hpf (hours post fertilization) spen-morphant embryos develop normally, they exhibit reduced contractility and bradycardia at 48 hpf. From 60 hpf onwards impaired spen function is associated with electrophysiological abnormalities, closely resembling human second grade av block as well as atrial and ventricular fibrillation. Transcriptional profiling of pooled spen-morphant hearts revealed connexin43 (cx43) to be severely downregulated. This finding was verified by qPCR, Western Blot analysis and in situ hybridization experiments. Consequently, we hypothesized cx43 to be transcriptionally controlled by spen and that inadequate function of spen lowers cx43 levels, thereby causing cardiac conduction abnormalities. Subsequently, we performed cx43-knockdown, which phenocopied the spen-morphants phenotype. Importantly, all loss-of function experiments could be rescued by overexpression of wild type cx43 mRNA. Moreover, sensitizing via double injection of sub-phenotypic concentrations of spen- and cx43-morpholinos resulted in a supra-additive effect, validating molecular crosstalk between spen and cx43 on the signaling level. Compared to unaffected controls, over 90% of sensitized embryos display the arrhythmia phenotype and show atrial- and ventricular fibrillation already at 48 hpf.

Conclusion

Our results demonstrate that the transcriptional regulator spen controls the transcription of connexin43 and that impairment of this mechanism leads to severe cardiac arrhythmia in zebrafish.

Iatrogenic Baclofen Neurotoxicity in ESRD: Recognition and Management

Baclofen is an oral derivative of gamma-aminobutyric acid (GABA) used to treat muscular spasticity from disorders of the central nervous system. However, it is also being used for a variety of other conditions such as musculoskeletal pain, myoclonus, and alcohol withdrawal. The elimination of baclofen is heavily dependent on intact renal function, and the contraindication for use in patients with insufficient renal function is not well recognized by healthcare providers. Here, the authors report a series of mild to severe cases of baclofen intoxication in patients with end-stage renal disease. In all cases, baclofen was initiated by either inpatient or outpatient healthcare providers and the patients generally presented with altered mentation, somnolence, and/or respiratory depression. All patients were treated with aggressive hemodialysis and made a full recovery. This paper will briefly review the literature regarding baclofen intoxication, safety of baclofen use in renal disease, and efficacy of extracorporeal therapy in the treatment of baclofen intoxication.

Successful treatment of severe ABO antibody-mediated rejection using bortezomib: a case report

BACKGROUND

Our program for ABO-incompatible renal transplantation includes antigen-specific immunoadsorption (extracorporeal columns with the A or B trisaccharides), rituximab, and standard maintenance immunosuppression. Anti-A or -B titers ≤ 8 in the indirect antiglobulin test (IAT) against panel A1 or B RBC are acceptable for transplantation.

CASE REPORT

A previously healthy, 15-month-old girl was diagnosed with Wilms' tumor and proteinuria. Denys-Drash syndrome was confirmed. Bilateral nephrectomy was performed. At 3.5 years of age she received an ABO-incompatible renal transplant from her father (A1 to O). The anti-A titers before transplantation were low. She was treated preoperatively with rituximab, immunoadsorption, immunoglobulin and mycophenolate mofetil (MMF). The maintenance immunosuppression protocol included basiliximab, tacrolimus, MMF, and prednisolone. The initial postoperative course was uncomplicated with rapid normalization of serum creatinine. The anti-A titers started to increase on postoperative day 5 (8 NaCl/16 IAT). Despite daily immunoadsorptions the titers rose to 1024 NaCl/1024 IAT on day 9. Renal function deteriorated and hemodialysis was started. A renal biopsy on day 9 showed acute severe antibody-mediated rejection. Additional treatment with bortezomib was given and after 2 doses the titers started to decline, renal allograft function improved and hemodialysis was stopped. On day 21 posttransplant the titers went down, creatinine was 28 μmol/L, and no more immunoadsorptions were performed.

CONCLUSION

By using bortezomib, we were able to successfully reverse a severe ABO antibody-mediated rejection.

Adipokine expression in brown and white adipocytes in response to hypoxia

BACKGROUND

Adipose tissue has emerged as an important endocrine regulator by secreting hormones referred to as adipokines. Recent studies showed that adipose tissue considerably responds to hypoxia. Although the impact of white adipose tissue on regulative processes is established, the importance of brown adipose tissue in adults has emerged just recently.

METHODS

Brown (BA) and white adipocytes (WA) were cultured either in the presence of chemical hypoxia-mimetics or under hypoxic atmosphere of 1% oxygen. Expression of hypoxia-inducible factor 1α (HIF- 1α) was assessed by western blot. The expression levels of several known HIF-1α-regulated proteins [vascular endothelial growth factor (VEGF), leptin, adiponectin, and angiotensinogen (AGT)] were quantified.

RESULTS

Both chemical hypoxia-mimetics and physical hypoxia led to increased nuclear HIF-1α expression and to decreased cytoplasmatic adiponectin in both cell types. In contrast, VEGF and AGT expression did not change upon hypoxic stimulation. Leptin was exclusively detectable in WA, while uncoupling-protein 1 (UCP-1) was expressed in BA only.

CONCLUSIONS

WA and BA are sensitive to hypoxia, in which HIF-1α expression is induced. Protein expression of adiponectin is hypoxia-dependent, whereas AGT, VEGF, leptin, and UCP-1 expression do not change secondary to hypoxia.

Expression of ATRAP in adipocytes and negative regulation by beta-adrenergic stimulation of JAK/STAT

Sympatho-adrenergic activity and the renin-angiotensin system are considered critical regulators of obesity and hypertension. The novel angiotensin II type 1 receptor-associated protein (ATRAP) has been demonstrated to modulate angiotensin II signalling in smooth muscle cells and cardiomyocytes. Adipose tissue expresses important renin angiotensin system components and contributes to cardiometabolic disease. However, ATRAP expression and regulation in adipocytes are unknown. We investigated expression of this novel modulator of angiotensin signalling and its regulation by beta-adrenergic receptors. We found ATRAP to be expressed in differentiated brown and white adipocytes. Stimulation of beta-adrenoceptors strongly suppressed ATRAP expression. We hypothesised a role for JAK/STAT signalling elements. Indeed, beta3-adrenergic stimulation robustly stimulated both STAT1 and STAT3 phosphorylation in a time- and dose-dependent manner. This effect was abrogated by inhibition of PKA and JAK2 signalling. Moreover, inhibition of JAK/STAT and PKA signalling reversed the beta3-adrenergic suppression of ATRAP expression. This study provides the first evidence for expression and adrenergic regulation of the angiotensin II signalling modulator ATRAP in adipocytes. Further, it indicates a novel regulatory link between beta-adrenergic and JAK/STAT signalling.

Vergleich von zentraler und peripherer Hornhautdicke zwischen Normalprobanden und Patienten mit chronischem Offenwinkelglaukom, Normaldruckglaukom und Pseudoexfoliationsglaukom

BACKGROUND

While many comparative data are available about central corneal thickness in different types of open angle glaucoma, peripheral corneal thickness has been much less investigated up to now. Thus, the aim of this study was to compare the central and peripheral corneal thicknesses in patients with primary open angle glaucoma (POAG), normal tension glaucoma (NTG) and pseudoexfoliation glaucoma (PEXG) to values of normal subjects.

PATIENTS

104 patients with POAG, 20 patients with NTG, 23 patients with PEXG and 127 normal subjects were investigated with the Orbscan II. The central corneal thickness and the peripheral corneal thickness at 3 mm distance from the centre were determined in 4 quadrants. The acoustic equivalent factor of 0.92 was not used. Patients with eye diseases, patients who had undergone eye surgery or wearers of contact lenses were excluded. Differences were analysed with the Bonferroni-adjusted Mann-Whitney U Test for statistical significance.

RESULTS

The median central corneal thickness in POAG was 600 +/- 35 microm, in NTG 577 +/- 31 microm, in PEXG 603 +/- 25 microm and in the control group 606 +/- 38 microm. The difference between NTG and the control group was statistically significant (p = 0.01). Superiorly the peripheral corneal thickness was lower in POAG (670 +/- 47 microm) and NTG (639 +/- 37 microm) compared to the control group (686 +/- 46 microm). Nasally the peripheral corneal thickness was lower in POAG (656 +/- 48 microm), NTG (658 +/- 55 microm) and PEXG (642 +/- 47 microm) compared to the control group (677 +/- 46 microm). Temporally and inferiorly there were only small differences compared to the control group. The differences in peripheral corneal thickness were not statistically significant.

DISCUSSION

In accord with literature data the central corneal thickness was lower in patients with normal tension glaucoma compared to normal subjects. Superiorly and nasally the peripheral corneal thickness was lower in patients with open angle glaucoma than in normal subjects which was, however, not statistically significant. To what extent these characteristics of the corneal architecture are relevant for the pathogenesis of open angle glaucomas has to be clarified in further larger trials.

Efficacy of ezetimibe/simvastatin 10/20 and 10/40 mg compared with atorvastatin 20 mg in patients with type 2 diabetes mellitus

AIM

This randomized, double-blind study evaluated the efficacy of switching from atorvastatin (ATV) 10 mg to ezetimibe/simvastatin (EZE/SIMVA) 10/20 mg, EZE/SIMVA 10/40 mg or doubling the dose of ATV from 10 to 20 mg in patients with type 2 diabetes (T2D).

METHODS

Eligible patients had haemoglobin A(1C)< or =10%, were aged > or =18 years and were on ATV 10 mg for > or =6 weeks before study entry. After a 4-week open-label ATV 10 mg run-in, patients were randomized to EZE/SIMVA 10/20 mg (n = 220), EZE/SIMVA 10/40 mg (n = 222) or ATV 20 g (n = 219) daily for 6 weeks.

RESULTS

Greater (p < or = 0.001) reductions in low-density lipoprotein cholesterol (LDL-C) (the primary end-point) were achieved by switching to EZE/SIMVA 10/20 mg (26.2%) or 10/40 mg (30.1%) than by doubling the dose of ATV to 20 mg (8.5%). EZE/SIMVA 10/20 mg and 10/40 mg produced greater (p < or = 0.001) reductions in total cholesterol, non-high-density lipoprotein cholesterol (HDL-C) and apolipoprotein B relative to ATV 20 mg. A reduction (p < or = 0.050) in C-reactive protein was observed with EZE/SIMVA 10/40 mg vs. ATV 20 mg. Similar reductions in triglycerides were observed across the three groups, and none of the treatments produced a significant change in HDL-C. A greater (p < or = 0.001) proportion of patients achieved LDL-C <2.5 mmol/l with EZE/SIMVA 10/20 mg (90.5%) and 10/40 mg (87.0%) than with ATV 20 mg (70.4%). Both EZE/SIMVA doses were generally well tolerated, with an overall safety profile similar to ATV 20 mg.

CONCLUSIONS

EZE/SIMVA 10/20 and 10/40 mg provided greater lipid-altering efficacy than doubling the dose of ATV from 10 to 20 mg and were well tolerated in patients with T2D.

Vitamins are associated with survival in patients with end-stage renal disease: a 4-year prospective study

BACKGROUND

Patients with end-stage renal disease are at high risk from premature death due mainly to cardiovascular disease and infections. Established risk factors do not sufficiently explain this increased mortality. We, therefore, investigated total mortality prospectively in a single-centre study in patients on hemodialysis and assessed the prognostic value of baseline disease status, laboratory variables including emerging risk factors, and the influence of vitamin treatment.

METHODS

Patients (n = 102) were followed-up for 4 years or until death (n = 49). Survival was calculated by the Kaplan-Meier method. Cox-proportional hazards model was used to determine independent predictors of total mortality.

RESULTS

The known risk factors age, baseline clinical atherosclerotic disease, low albumin and increased cardiac troponin T were significantly associated with mortality. Patients who received multivitamins during follow-up had a significantly lower mortality risk than those not receiving this treatment (hazard ratio 0.29, 95% confidence interval 0.15-0.56). These associations remained significant after adjustment for age, cardiovascular disease, albumin and cardiac troponin T at baseline.

CONCLUSIONS

The present study suggests that multivitamin supplementation in patients with end-stage renal disease is closely associated with reduced mortality due to all causes. These observations have to be validated in randomized clinical intervention trials.

In Heavy Drinkers, Fatty Acid Ethyl Esters Remain Elevated for Up to 99 Hours

BACKGROUND

Both medical and forensic needs require reliable detection of earlier ethanol intake after the disappearance of ethanol from blood. The esters of ethanol with free fatty acids (FAEEs) are candidate markers of this kind. However, it is unknown whether FAEEs can serve as a marker for a single prior ethanol intake. In addition, the period for which FAEEs are elevated is unknown. Therefore, we measured FAEEs in heavy drinkers admitted to detoxification, and in healthy subjects after a drinking experiment.

METHODS

Blood from 30 heavy drinkers was obtained for up to 5 days during a detoxification period in a psychiatric hospital. In addition, 17 healthy subjects who participated in a drinking experiment and who were abstinent thereafter gave blood during a similar time period for analysis of FAEEs. Fatty acid ethyl esters were measured by gas chromatography-mass spectroscopy.

RESULTS

Heavy drinkers had much higher ethanol and FAEEs concentrations than healthy subjects; however, in both groups, FAEEs decreased rapidly during the first day. Only in heavy drinkers, elevated concentrations of FAEEs were observed at days 2 to 4. Concentrations of FAEEs were not associated with serum triglycerides or patients' body mass index.

CONCLUSIONS

It is concluded that kinetics of FAEEs are different in heavy drinkers compared with healthy subjects and that FAEEs are of limited value for the detection of prior single ethanol intake.

Post-hoc analysis on the CD14 C(-260)T promoter polymorphism and coronary heart disease

Functional C(-260)--> T polymorphism in the promoter of the CD14 gene has been reported to be associated with coronary heart disease (CHD). The functional role of the polymorphism, however, is still a matter of debate, since several studies have not proved its effect on clinical outcomes associated with atherosclerosis. Cardiovascular-related morbidity and mortality was assessed in a post-hoc approach four years after baseline characterization of patients (male/female n = 36/32) with angiographically proven coronary heart disease. CD14 C(-260)--> T promoter genotype was determined at baseline. Seventeen out of 20 CHD patients with non-lethal cardiovascular events carried at least one T-allele. CD14 T-260 allele carriers have a 3.59-fold (95 % confidence interval: 1.11-6.75) increased risk for non-lethal cardiovascular events (Kaplan-Meier plot: log rank test p = 0.029). All patients with lethal outcomes (n = 6) were also T-allele carriers. Multivariate logistic regression analysis among CHD patients including age, established risk factors and the C(-260)--> T polymorphism as covariates and non-lethal events as a dependent variable confirmed the independent prospective effect of the T-allele on cardiovascular outcomes in this subset. Further evidence is provided for the role of CD14 C(-260)--> T promoter polymorphism as a genetic susceptibility marker of atherosclerosis in patients with an advanced clinical course of the disease. Due to the small sample size and post-hoc character of the study large-scale prospective studies that monitor patients with proven CHD are needed to confirm these findings.

Early Recurrence of Nephrotic Syndrome (Immunoglobulin M Nephropathy) After Renal Transplantation Successfully Treated With Combinations of Plasma Exchanges, Immunoglobulin, and Rituximab

In contrast to focal segmental glomerulosclerosis, which is well known to recur early in a renal graft, there are only few cases described with recurrence of immunoglobulin M (IgM) nephropathy after transplantation. We herein describe a patient with early recurrence of IgM nephropathy. A 15-year-old boy with nephrotic syndrome (IgM nephropathy) proceeding to end-stage renal disease was on dialysis before living related renal transplantation. Native kidneys were not removed. Standard immunosuppression including steroids, tacrolimus, and mycophenolate mofetil yielded initially good graft function with the s-creatinine falling to 73 micromol/L. Proteinuria was present on day 1, increasing to 20 g/L after 3 days. S-creatinine increased to 158 micromol/L and urine production diminished. A graft biopsy showed no rejection or glomerulopathy but protein vacuoles were seen within tubular cells indicating massive proteinuria. Treatment with plasma exchanges, immunoglobulin, and steroids was started. Hemodialysis was necessary. Proteinuria improved to 3.5 g/L, but s-creatinine continued to rise and a second graft biopsy showed vascular rejection (Banff type IIA). The patient was treated with antithymocyte globulin and further plasma exchanges. A single dose of rituximab was given. Five months after transplantation the s-creatinine was 67 micromol/L and there was no proteinuria. In this case early recurrence of nephrotic syndrome occurred on the first posttransplant day in combination with later occurring vascular rejection. Successful treatment included a combination of plasma exchanges, rituximab, immunoglobulin, and antithymocyte globulin.

Endocrine and behavioural plasticity in response to juvenile stress in the semi-precocial rodent Octodon degus

The present study in the South American rodent Octodon degus shows for the first time that the postnatal development of hypothalamic-pituitary-adrenal axis function in this semi-precocial species differs from that of altricial rodents, i.e. rats or mice, in several aspects. Our experiments revealed a particular pattern of hypothalamic-pituitary-adrenal axis activity during the first 3 weeks of life characterized by (i) a period of low plasma glucocorticoid concentrations, during which (ii) brief stress exposure (1 h parental separation) is able to elevate glucocorticoids significantly. In addition, (iii) repeated stress exposure (1 h parental separation daily) during the first 3 weeks of life resulted in females, but not in males, in an attenuated separation-induced increase of glucocorticoids, and a higher behavioural activity in both sexes at postnatal day 21. These data indicate that parental separation early in life acts as a 'strong' stressor in this species, which on the long run can alter endocrine stress response at the time of weaning in a sex-specific manner. These findings support the role of the hypothalamic-pituitary-adrenal axis as one of the key factors mediating the effects of early life stress on the neuronal network and behaviour in O. degus.

Detection of Recent Ethanol Intake With New Markers: Comparison of Fatty Acid Ethyl Esters in Serum and of Ethyl Glucuronide and the Ratio of 5-Hydroxytryptophol to 5-Hydroxyindole Acetic Acid in Urine

BACKGROUND

At present, recent ethanol consumption can be routinely detected with certainty only by direct measurement of ethanol concentration in blood or urine. Because ethanol is rapidly eliminated from the circulation, however, the time span for this detection is in the range of hours. Several new markers have been proposed to extend the detection interval, but their characteristics have not yet justified their use in routine clinical practice. We therefore investigated three new markers and compared their kinetics and sensitivities: (1) fatty acid ethyl esters (FAEEs) in serum, (2) ethyl glucuronide (EtG) in urine, and (3) the ratio of 5-hydroxytryptophol to 5-hydroxyindole acetic acid (5-HTOL/5-HIAA) in urine.

METHODS

Seventeen healthy men participated in a drinking experiment. Blood and urine samples were collected twice daily on three consecutive days and once daily on days 4 and 5. Ethanol concentration was determined by gas chromatography, FAEE levels, by gas chromatography with mass spectrometry, EtG concentration, by liquid chromatography-tandem mass spectrometry, and 5-HTOL/5-HIAA ratio, by high-performance liquid chromatography.

RESULTS

The peak serum ethanol concentrations of the subjects ranged from 5.4 to 44.7 mmol/liter (mean +/- SD, 30.1 +/- 9.1 mmol/liter). In the case of the serum ethanol determination, 100% sensitivity was reached only immediately after the end of the drinking experiment, and in the case of FAEE levels and 5-HTOL/5-HIAA ratio, it tested for 6.7 hr after the end of the ethanol intake. Thereafter, these latter parameters declined until 15.3 hr (FAEEs) and 29.4 hr (5-HTOL/5-HIAA), subsequently remaining in a stable range until 78.5 hr without further decrease. In contrast, EtG concentration showed 100% sensitivity until 39.3 hr and thereafter decreased, falling to below the limit of quantification of 0.1 mg/liter at 102.5 hr.

CONCLUSION

After moderate drinking, EtG in the urine proved to be a superior marker of recent ethanol consumption in healthy subjects. This is because EtG is a direct ethanol metabolite, it occurs in the urine only when ethanol has been consumed, and its sensitivity remains at the level of 100% for 39.3 hr.

Prevalences of hyperhomocysteinemia, unfavorable cholesterol profile and hypertension in European populations

BACKGROUND

Hyperhomocysteinemia (HHCY) is a risk factor for cardiovascular diseases (CVD). HHCY may interact with hypertension (HTEN) and an unfavorable cholesterol profile (UNFAVCHOL) to alter the risk of CVD.

OBJECTIVES

To estimate the prevalences of HHCY (1) isolated and (2) in combination with UNFAVCHOL and/or HTEN in different age categories. To provide information that may improve the screening and treatment of subjects at risk of CVD.

DESIGN

Cross-sectional data on 12,541 men and 12,948 women aged 20 + y were used from nine European studies.

RESULTS

The prevalence of isolated HHCY was 8.5% in subjects aged 20-40 y, 4.7% in subjects aged 40-60 y and 5.9% in subjects aged over 60 y. When combining all age groups, 5.3% had isolated HHCY and an additional 5.6% had HHCY in combination with HTEN and/or UNFAVCHOL. The combinations of risk factors increased with age and, except for HHCY&UNFAVCHOL, were more prevalent than predicted by chance. Of the young subjects (20-40 y), 24% suffered from one or more of the investigated CVD risk factors. This figure was 75.1% in the old subjects (60+ years).

CONCLUSIONS

A substantial number of subjects in selected European populations have HHCY (10.9%). In half of these cases, subjects suffer also from other CVD risk factors like UNFAVCHOL and HTEN. Older people in particular tend to have more than one risk factor. Healthcare professionals should be aware of this when screening and treating older people not only for the conventional CVD risk factors like UNFAVCHOL and HTEN but also HHCY, as this can easily be reduced through increased intake of folic acid via supplement or foods fortified with folic acid.

Molecular remission of CML after autotransplantation followed by adoptive transfer of costimulated autologous T cells

Four patients with chronic myelogenous leukemia (CML) that was refractory to interferon alpha (two patients) or imatinib mesylate (two patients), and who lacked donors for allogeneic stem cell transplantation, received autotransplants followed by infusions of ex vivo costimulated autologous T cells. At day +30 (about 14 days after T-cell infusion), the mean CD4+ cell count was 481 cells/microl (range 270-834) and the mean CD8+ count was 516 cells/microl (range 173-1261). One patient had a relative lymphocytosis at 3.5 months after T-cell infusion, with CD4 and CD8 levels of 750 and 1985 cells/microl, respectively. All the four patients had complete cytogenetic remissions early after transplantation, three of whom also became PCR negative for the bcr/abl fusion mRNA. One patient, who had experienced progressive CML while on interferon alpha therapy, became PCR- post transplant, and remained in a molecular CR at 3.0 years of follow-up. All the four patients survived at 6, 9, 40, and 44 months post transplant; the patient who remained PCR+ had a cytogenetic and hematologic relapse of CML, but entered a molecular remission on imatinib. Autotransplantation followed by costimulated autologous T cells is feasible for patients with chronic phase CML, who lack allogeneic donors and can be associated with molecular remissions.

Tomato profilin Lyc e 1: IgE cross-reactivity and allergenic potency

BACKGROUND

To date, very little data are available about the nature of tomato allergens. Immunoglobulin E (IgE) cross-reactive profilins have been suggested to account for allergic symptoms in patients suffering from tomato allergy.

METHODS

The cDNA of tomato profilin was amplified by reversely transcribed polymerase chain reaction (RT-PCR) from total RNA extracted from ripe tomato fruit. The gene was cloned into the pET101D expression plasmid and the protein was produced in Escherichia coli BL21. Purification was performed via poly-l-proline (PLP) affinity chromatography. IgE reactivity of recombinant tomato profilin was investigated by immunoblot and enzyme-linked immunosorbent assay. IgE-inhibition studies were performed to analyse cross-reactivity with other profilins. To determine the allergenic activity of the recombinant protein, basophil histamine release assays using sera of patients with adverse reactions to tomato were performed.

RESULTS

Profilin was identified as a new minor allergen in tomato fruits. The recombinant tomato profilin comprises 131 amino acids and high sequence identity to other allergenic food and pollen profilins. It was shown to be IgE-reactive with a prevalence of 22% (11/50) in tomato-allergic patients. In patients with tomato allergy and multiple sensitization to other foods and birch pollen, IgE directed against tomato profilin showed a strong cross-reactivity with profilins from plant food sources and birch pollen. The tomato profilin was able to induce mediator release from human basophils.

CONCLUSION

The tomato profilin is a minor allergen in tomato fruit. Thus, it shows biological activity, as confirmed by in vitro histamine release assays with human basophils and thereby has the potential to account for clinical symptoms in tomato-allergic patients.

Multiple and synergistic deregulations of apoptosis-controlling genes in pancreatic carcinoma cells

Inability to die by apoptosis is one of the reasons for the deregulated growth of tumour cells and the frequently observed failure of chemotherapy. In this study we thought to identify the common and functionally important characteristics responsible for the apoptosis resistance of pancreatic tumour cells. We analysed cell surface expression level of death receptors CD95 and TRAIL-R1-4 as well as the expression profile of sixteen apoptosis-relevant proteins in five pancreatic carcinoma cell lines Capan1, Colo357, PancTuI, Panc89 and Panc1. These data were evaluated in the context of sensitivity towards anti-CD95 and TRAIL-mediated apoptosis. Here we report that except for resistant Panc1 cells, which only marginally expressed CD95, all other cell lines showed comparable levels of CD95 and TRAIL receptors irrespectively of their apoptotic phenotype. Interestingly, we found that the elevated expression of FLIP, Bcl-x_L and IAP in parallel with a downregulation of FADD and Bid was common for the resistant cell lines. Consequently, stable overexpression of XIAP, Bcl-x_L or dominant negative FADD in sensitive cells significantly reduced the death receptor mediated apoptosis while the overexpression of Bid rendered the resistant cells sensitive.

Influence of preapheresis clinical factors on the efficiency of CD34+ cell collection by large-volume apheresis

We evaluated 120 leukapheresis procedures (93 patients), in order to detect clinical factors that influence the efficiency of CD34+ collection using Cobe Spectra trade mark cell separators. Hematocrit was >27% and platelet count >30 000/microl in >95% of patients. Platelet transfusions were given if the postprocedure count was &<20 000/microl. Multiple regression analysis was used to analyze putative factors, and a predictive equation defined by stepwise regression modeling. The mean efficiency was 0.59 (s.d. 0.27). Sex (M>F; P=0.01), the volume processed (inversely; P=0.01) and CD34+ cell count (inversely; P=0.04) were associated with efficiency, whereas hematocrit, platelet or leukocyte count, catheter type and patient weight were not. The effect size for predictive factors was small (R(2)=0.21). Adverse events were limited to hypocalcemia. We conclude that female sex, volume processed and CD34+ cell count adversely influence the efficiency of CD34+ cell leukapheresis. However, the impact of volume and CD34+ cell count is small, and likely to be offset by the influence of these same factors on overall yield. Leukapheresis appears to be safe and efficient for autologous blood and marrow transplantation patients with hematocrit >27% and platelet count >30 000/microl.

Treatment of paediatric pontine glioma with oral trophosphamide and etoposide

To evaluate the overall survival of paediatric patients with pontine gliomas treated with oral trophosphamide and etoposide. Patients between 3 and 17 years of age with either typical diffuse pontine glioma on MRI or histologically proven anaplastic astrocytoma/glioblastoma multiforme located in the pons, were eligible. Treatment consisted of oral trophosphamide 100 mg x m(-2) x day(-1) combined with oral etoposide at 25 mg x m(-2) x day(-1) starting simultaneously with conventional radiation. Twenty patients were enrolled (median age 6 years, male : female=9 : 11). Surgical procedures included: no surgery: five, open biopsy: three, stereotactic biopsy: six, partial resection: three, and sub-total resection: three. Histological diagnoses included pilocytic astrocytoma: one, astrocytoma with no other specification: three, anaplastic astrocytoma: three, glioblastoma multiforme: eight, no histology: five. The most frequent side effects were haematologic and gastrointestinal. There was no toxic death. The response to combined treatment in 12 evaluable patients was: complete response: 0, partial response: three, stable disease: four, and progressive disease: five. All tumours progressed locally and all patients died. The overall median survival was 8 months. The overall survival rates at 1 and 4 years were: 0.4 and 0.05 respectively. This was not different from a control group of patients documented in the same population. Oral trophosphamide in combination with etoposide did not improve survival of pontine glioma patients. The treatment was well tolerated and should be evaluated for more chemoresponsive paediatric malignancies.

Addition of glucose to a fatty meal delays chylomicrons and suppresses VLDL in healthy subjects

BACKGROUND

Postprandial lipemia has been shown in a number of studies to be associated with atherosclerosis. However, the test meals used in these studies were heterogeneous particularly in their carbohydrate content, which may be important for the resulting lipemia and which makes comparison between different studies difficult. We studied the effect of 75 g glucose added to a fatty meal on various lipoproteins and on gastric emptying.

MATERIALS AND METHODS

Fourteen healthy young volunteers were studied in the fasting state and until 7 h postprandially. In a crossover design, each subject received an oral fat load (1 g fat kg(-1) body weight) with or without 75 g glucose. Triacylglycerol (TG) and free fatty acids (FFA) were then measured in whole blood and lipoproteins were separated off by ultracentrifuging. Gastric emptying was determined by the (13)C breath test.

RESULTS

The addition of 75 g glucose to a fatty meal had two different effects. Gastric emptying was delayed by about 2 h and the chylomicron response was consequently postponed. In addition, the postprandial increase in VLDL triacylglycerol was reduced by 40%, which may be due to the pronounced FFA depression during the glucose-induced rise in insulin.

CONCLUSIONS

75 g glucose added to an oral fat load causes a delay of the chylomicron response and a marked suppression of the postprandial increase in VLDL.

A vesicle transport system inside chloroplasts

Intracellular transport via membrane vesicle traffic is a well known feature of eukaryotic cells. Yet, no vesicle transport system has been described for prokaryotes or organelles of prokaryotic origin, such as chloroplasts and mitochondria. Here we show that chloroplasts possess a vesicle transport system with features similar to vesicle traffic in homotypic membrane fusion. Vesicle formation and fusion is affected by specific inhibitors, e.g. nucleotide analogues, protein phosphatase inhibitors and Ca2+ antagonists. This vesicle transfer is an ongoing process in mature chloroplasts indicating that it represents an important new pathway in the formation and maintenance of the thylakoid membranes.

Vitamin supplementation can markedly reduce the homocysteine elevation induced by fenofibrate

Elevated homocysteine concentrations are a risk factor for atherosclerotic disease. Recently it was reported that lipid lowering with fibrates increases homocysteine by up to 40%. Since elevated homocysteine concentrations can readily be lowered by vitamin supplementation, a randomized, double-blind crossover study was performed to investigate the effect of fenofibrate plus folic acid, vitamin B6 and B12 versus fenofibrate plus placebo in hyperlipidemic men. The crossover study comprised a run-in period of 6 weeks, a first treatment phase of 6 weeks, a washout phase of 8 weeks and a second treatment phase of 6 weeks. Vitamins were given at doses of 650 microg folic acid, 50 microg vitamin B12 and 5 mg vitamin B6 per day for a period of 6 weeks. After fenofibrate plus placebo the increase in homocysteine concentration was 44+/-47%. After fenofibrate plus vitamins it was 13+/-25%, being significantly lower than without vitamins. The increase in homocysteine in response to fenofibrate may counteract the cardioprotective effect of lipid lowering. The addition of vitamins involved in homocysteine metabolism can prevent most of the homocysteine increase seen after fenofibrate plus placebo. Addition of these vitamins to fenofibrate may therefore be warranted for routine use.

Effects of fenofibrate and gemfibrozil on plasma homocysteine

Fenofibrate increases plasma homocysteine. Because the concentration of plasma homocysteine depends on renal function, we postulate that increases in plasma homocysteine are a result of the known impairment of renal function caused by fenofibrate. Gemfibrozil, another fibrate, does not affect renal function. In a crossover study we tested whether gemfibrozil would raise homocysteine. 22 patients who had hypertriglyceridaemia were given 900 mg gemfibrozil or 200 mg fenofibrate daily for 6 weeks. Lipids were altered similarly, but homocysteine, creatinine, and cystatin C were raised by fenofibrate but not by gemfibrozil (p for differences between treatment effects: 0.007, 0.006, and 0.040, respectively). We propose gemfibrozil should be the fibrate of choice.

An improved method for the rapid assessment of persisting chylomicron remnant concentrations

Persisting chylomicron remnant concentrations have been linked to premature atherosclerosis. The analysis of persisting chylomicron remnant concentrations by an oral triglyceride tolerance test, however, is time-consuming for the study subjects and requires large resources in the laboratory. Therefore, only small numbers of subjects have been studied in the past. We describe major improvements of the testing procedure in regard of composition of the fatty meal, of patient testing, and measurement of postprandial remnants. Shifting the time of the (ready-to-use) fatty drink from the morning hours to bedtime was well accepted by the study subjects and allowed the analysis of blood samples drawn at the morning with minimal impact on the participants' time and with minimal interferences by confounding factors (e.g. smoking, additional food intake, physical activity). Chylomicron remnants were measured by fluorometry of the supernatant after ultracentrifugation. This procedure was sensitive, was specific for chylomicron remnants, and was easy to perform. The biological validity of the improved procedure was evaluated by studying type III hyperlipoproteinemia patients and normolipemic apolipoprotein (Apo) E2 homozygotes. In conclusion, this improved test permits the rapid testing for persisting chylomicron remnants in the clinical routine and in large epidemiological studies.

Factors explaining the difference of total homocysteine between men and women in the European Investigation Into Cancer and Nutrition Potsdam study

Interestingly, plasma total homocysteine (tHcy) concentration is consistently higher in men than in women. This observation deserves further investigations because elevated tHcy concentrations have been shown to be independently associated with coronary, peripheral, and cerebral vascular diseases. It was the aim of the present study to define major determinants of plasma tHcy in a healthy middle-aged German population under particular consideration of the gender factor. The study population was obtained from an ongoing recruitment procedure for a cohort study and comprised 336 men and women, aged 40 to 65 years. Exclusion criteria were elevated creatinine levels in blood, history of skin or atherosclerotic diseases, current use of vitamins or other supplements, and heavy smoking. Plasma tHcy, folate, vitamin B12, vitamin B6, creatinine, testosterone and estradiol, protein, and hematocrit were measured. Fat-free mass was assessed by skinfold thickness. The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR), a key enzyme of folate and homocysteine metabolism, was determined by polymerase chain reaction (PCR) with restriction enzyme analysis. In this population, plasma tHcy ranged from 5 to 46 micromol/L. The frequency of the T allele of the MTHFR was 0.29, which is lower than in other populations. A total of 54.2% of this population was homozygote for the wild-type, 39.6% heterozygote, and 6.2% homozygote for the mutation. tHcy correlated negatively with folate and cobalamin concentration in blood and positively with creatinine. No correlation was seen with vitamin B6. From the gender-related variables, tHyc correlated significantly with fat-free mass and testosterone and inversely with estradiol. The difference between gender with regard to tHcy was mainly explained by differences in fat-free mass, but also by estradiol concentrations. The following contributions to the variation of tHcy were seen in a multivariate regression model: plasma cobalamin (11%), creatinine (11%), plasma folate (8%), fat-free mass (5%), estradiol (2%), MTHFR polymorphisms (2%), and plasma protein (1%). We concluded that tHcy in the general population has a variety of determinants ranging from nutrition, internal metabolic parameters to gender-related variables.