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A Hartmann

Publications and source records attributed to A Hartmann.

At least 217 records · Page 12Linked to original sources
PubMed1998

The evolution of chromosomal instability in Chinese hamster cells: a changing picture?

PURPOSE: To investigate the kinetics of chromosomal instability induced in clones of Chinese hamster cells following X-irradiation. MATERIALS AND METHODS: X-irradiated clones of GM10115, human-hamster hybrid cells containing a single human chromosome 4 (HC4), have been previously established. These clones were defined as unstable if they contained > or = three subpopulations of cells with unique rearrangements of HC4 as detected by FISH. Stable and unstable clones were analysed by FISH and Giemsa staining at various times post-irradiation. RESULTS: While most of the stable clones continued to show chromosomal stability of HC4 over time, one became marginally unstable at approximately 45 population doublings post-irradiation. Clones exhibiting chromosomal instability had one of several fates. Many of the unstable clones were showed similar levels of instability over time. However, one unstable clone became stable with time in culture, while another became even more unstable over time. Cytogenetic analyses of all clones after Giemsa staining indicated that in some clones the hamster chromosomes were rearranged independent of HC4, demonstrating increased frequencies of chromatid breaks and dicentric chromosomes. The majority of the unstable clones also had higher yields of chromatid gaps. CONCLUSIONS: These data demonstrate the dynamic nature of chromosomal instability as measured by two different cytogenetic assays.

Animals↗
PubMed1998

Renal effects of losartan and amlodipine in hypertensive patients with non-diabetic nephropathy.

BACKGROUND: The objective of this study was to examine the effects of angiotensin II receptor blocker losartan versus the calcium channel blocker amlodipine on proteinuria, renal haemodynamics, glomerular sieving and tubular function in hypertensive patients with non-diabetic nephropathy. METHODS: The study design was a prospective, double blind, placebo controlled, randomized crossover trial with amlodipine and losartan. Renal parameters were measured at baseline and at the end of each 4-week active treatment period. Fifteen patients with a diagnosis of non-diabetic renal disease and hypertension were included. RESULTS: Mean arterial blood pressure decreased from 123+/-13 mmHg at baseline to 113+/-10 mmHg (P<0.01) on losartan and to 114+/-10 mmHg on amlodipine (P<0.01). Urinary albumin excretion significantly decreased from 3510+/-2586 mg/24 h at baseline to 2684+/-2051 mg/24 h (P<0.01) on losartan and increased non-significantly to 3748+/-3355 mg/24 h on amlodipine. Filtration fraction significantly decreased from a baseline value of 22.8+/-9.3% to 21.2+/-10.2% (P<0.05) on losartan and increased to 23.6+/-8.9% (ns) on amlodipine. Either drug did not significantly alter glomerular sieving of neutral dextrans. CONCLUSION: Our results demonstrate that losartan, but not amlodipine, decreased albumin excretion in hypertensive patients with non-diabetic nephropathy.

Adult↗
PubMed1998

Routine perioperative antibiotic prophylaxis in renal transplantation.

BACKGROUND: Perioperative antibiotic prophylaxis may prevent infection following renal transplantation but it also contributes to development of resistant microorganisms. With refined surgical techniques, improved graft preservation, and immunosuppressive monitoring during recent decades one can question the present use of perioperative antibiotic prophylaxis. We retrospectively evaluated the incidence of infection in our renal transplant centre where antibiotic prophylaxis is not routinely used in renal recipients. Concurrently we performed a survey of perioperative antibiotic use to establish the current world-wide practice. METHODS: Infection episodes were evaluated from records of 448 adult renal transplant recipients (January 1994 to August 1996) at our centre. A questionnaire was mailed to 103 centres addressing the number of kidney transplantations in 1995, donor source (living vs cadaveric) and details on use of perioperative antibiotic prophylaxis. RESULTS: Single-centre study. Renal transplantation was performed without antibiotic prophylaxis in 377 patients (84%). Thirteen patients (3.4%) had early postoperative infections, nine with urinary-tract infection tended to have urinary catheter for a longer period than those without infection (5.0 +/- 2.7 vs 3.4 +/- 1.4 days, P = 0.27) and cadaveric kidney recipients to have higher incidence of infections (4.5 vs 1.5% P = 0.14). All infection episodes were successfully treated. The infection incidence in 71 (16%) 'high-risk' patients selected for antibiotic treatment was 4.2%. World-wide survey. Data were obtained from 101 centres in five continents representing 10532 renal transplants. Ninety centres (89%) used perioperative antibiotic prophylaxis. CONCLUSION: The infection incidence in patients who did not receive perioperative antibiotic prophylaxis was the same as in a small group of selected patients who received prophylaxis. The incidence was lower than usually reported in the literature. In contrast perioperative antibiotic prophylaxis is given to all patients in almost 90% of transplant centres worldwide. A reduction of prophylactic antibiotic use is encouraged.

Adult↗
PubMed1998

Insulin resistance is a common denominator of post-transplant diabetes mellitus and impaired glucose tolerance in renal transplant recipients.

BACKGROUND: Post-transplant diabetes mellitus is a known complication of steroid therapy in renal transplant recipients. Both insulin resistance and insulin deficiency have been shown to be necessary for development of post-transplant diabetes mellitus. It is not known whether recipients with impaired glucose tolerance have similar degree of insulin resistance or deficient insulin response as recipients with post-transplant diabetes mellitus. METHOD: To address this question, we used an oral glucose tolerance test to categorize 46 renal transplant recipients on triple immunosuppressive medication to groups with normal glucose tolerance, impaired glucose tolerance or post-transplant diabetes mellitus. Insulin sensitivity was measured using a hyperinsulinaemic euglycaemic clamp. Insulin response was calculated from the increase in serum insulin concentration during the oral glucose tolerance test. RESULTS: Twenty-five were categorized to normal glucose tolerance, 15 to impaired glucose tolerance and six to post-transplant diabetes mellitus. There were no statistically significant differences between the groups regarding prednisolone dose, azathioprine dose, use of beta-blocker, age, gender, weight, waist-hip ratio, body mass index, donor source, smoking habits, or first-degree relatives with histories of diabetes mellitus. The impaired glucose tolerance and post-transplant diabetes mellitus groups showed a significant reduction in insulin-stimulated glucose disposal rate (mg/kg.min) compared to the normal glucose tolerance group (4.6 +/- 1.6 and 3.4 +/- 1.3 respectively vs 7.1 +/- 2.4, P < 0.05). The insulin response (picomol/l) was not different between the normal glucose tolerance and impaired glucose tolerance groups but was significantly reduced in the post-transplant diabetes mellitus group (448 +/- 310 and 450 +/- 291 respectively vs 170 +/- 128, P < 0.05). CONCLUSION: Insulin resistance is a common denominator of post-transplant diabetes mellitus and impaired glucose tolerance in renal transplant recipients.

Adult↗
PubMed1998

Does intratesticular testosterone administration modify the evolution of transitory testicular ischemia in pre-pubertal rats?

PURPOSE: Testicular torsion followed by ischemia results in variable degrees of infertility and until now there appears to be no effective way to recover it. Testosterone participation in the maintenance of male sexual organs and spermatogenesis led us to hypothesize that intratesticular administration could recover ischemic injury. MATERIALS AND METHODS: We divided 40 Wistar rats in 2 groups, of 20 each. One group was control and the other underwent a 120-minute testicular ischemia by means of a vascular clamp on the left spermatic cord. Each group was further subdivided in 2 subgroups. The first one was observed and the second received intratesticular testosterone 25 mg. starting on the third day after injury and during the next 7 consecutive days. Half the animals were sacrificed 30 days after injury and the remaining ones after 60 days. Weight, volume, number of seminiferous tubules, histology and spermatogenesis of the same side and contralateral testes were examined. For statistical analysis ANOVA and Fisher's tests were applied. RESULTS: It was found that testosterone was capable of acting upon volume and weight of the left testis (p=0.0001). The animals receiving intratesticular testosterone showed lower testicular weight and volume after 30 and 60 days, respectively. This subgroup also showed a higher number of seminiferous tubules, modified histology and absent spermatogenesis suggesting testicular atrophy. CONCLUSIONS: We concluded that intratesticular injection of testosterone 25 mg. once a day during 7 consecutive days after transitory testicular ischemia causes ipsilateral testis atrophy. The animals in control group showed testicular histological recovery 60 days after injury. There were no significant histological differences in the contralateral testes.

Analysis of Variance↗
PubMed1998

Cigarette smoking as a determinant of high-grade carotid artery stenosis in Hispanic, black, and white patients with stroke or transient ischemic attack.

BACKGROUND AND PURPOSE: We sought to investigate the association of cigarette smoking with high-grade carotid artery stenosis in Hispanic, black, and white patients with cerebral ischemia in two independent samples. METHODS: Prospectively collected data from the Northern Manhattan Stroke Study (NOMASS) (n=431) and the Berlin Cerebral Ischemia Databank (BCID) (n=483) were used separately for a cross-sectional study estimating the association between cigarette smoking and high-grade carotid stenosis (defined as a luminal narrowing of > or =60%, diagnosed by duplex and/or Doppler ultrasound). In both studies, cerebral ischemia patients with normal sonographic findings or nonstenosing plaques of their carotid arteries served as a comparison group. Multivariate logistic regression models were used for statistical tests to determine the association between smoking and the dependent variable for high-grade carotid stenosis. Age, sex, hypertension, diabetes, hypercholesterolemia, and race/ethnicity were considered potential confounders. Further analyses of the NOMASS data estimated the effect of the amount of cigarette use and the impact of race/ethnicity. RESULTS: High-grade carotid stenoses were found in 14% of the NOMASS and in 21% of the Berlin patients. In Berlin the entire sample was white, whereas in New York only 19% of the cohort were white. In both samples, smoking was independently associated with severe carotid stenosis (NOMASS: odds ratio [OR], 1.5; 95% confidence interval [CI], 1.1 to 2.0; BCID: OR, 3.9; 95% CI, 2.4 to 6.4). Patients smoking 20 pack-years or more showed a significant association (OR, 2.0; 95% CI, 1.1 to 3.9), whereas no significant effect was found for lower amounts of cigarette use. In NOMASS, white smokers displayed a significant (OR, 3.2; 95% CI, 1.1 to 8.9) association with high-grade carotid stenosis, the association for black smokers was less strong, and no association was found among Hispanics. CONCLUSIONS: Smoking is an independent determinant of severe carotid artery stenosis in patients with focal cerebral ischemia. The association differs by race/ethnicity, with the greatest effect observed among whites.

Adult↗
PubMed1998

Morbidity of intracranial hemorrhage in patients with cerebral arteriovenous malformation.

BACKGROUND AND PURPOSE: Decisions on invasive arteriovenous malformation (AVM) treatment are currently based on natural-course risk estimates of AVM bleeding and assumptions on morbidity from cerebral hemorrhage in general. However, morbidity of AVM hemorrhage has rarely been reported. We sought to assess the morbidity of intracranial hemorrhage in patients with cerebral AVMs. METHODS: From a prospective AVM database, 119 patients were analyzed: 115 had a hemorrhage as the diagnostic event, and 27 of them suffered a second hemorrhage during follow-up; an additional 4 patients had other diagnostic symptoms but bled during follow-up. The type (parenchymal, subarachnoid, intraventricular) and location of AVM hemorrhage were determined by CT/MR brain imaging. Disability and neurological impairment were assessed with the Barthel Index, the Rankin Scale, and the National Institutes of Health Stroke Scale, with a mean follow-up time of 16.2 months. RESULTS: Of the 115 incident hemorrhages, 34 (30%) were subarachnoid, 27 (23%) parenchymal, 18 (16%) intraventricular, and 36 (31%) in combined locations. In 54 patients (47%; 95% confidence interval [CI], 38% to 56%) the incident hemorrhage resulted in no neurological deficit, and an additional 43 patients (37%; 95% CI, 28% to 46%) were independent in their daily activities (Rankin 1). Fifteen patients (13%; 95% CI, 7% to 19%) were moderately disabled (Rankin 2 or 3), and 3 (3%; 95% CI, 0% to 6%) were severely disabled (Rankin > or =4). Parenchymal hemorrhages were most likely to result in a neurological deficit (52%). Type and morbidity of hemorrhage during follow-up were similar to incident events. Twenty (74%) of 27 patients with both incident and follow-up hemorrhages were normal or independent (Rankin 0 or 1). None of the patients with a hemorrhage during follow-up died during the observation period. CONCLUSIONS: Hemorrhage from cerebral AVMs appears to have a lower morbidity than currently assumed. This finding encourages a reevaluation of the risks and benefits of invasive AVM treatment.

Activities of Daily Living↗
PubMed1998

Feeding artery pressure and venous drainage pattern are primary determinants of hemorrhage from cerebral arteriovenous malformations.

PURPOSE: The purpose of this study was to define the influence of feeding mean arterial pressure (FMAP) in conjunction with other morphological or clinical risk factors in determining the probability of hemorrhagic presentation in patients with cerebral arteriovenous malformations (AVMs). METHODS: Clinical and angiographic data from 340 patients with cerebral AVMs from a prospective database were reviewed. Patients were identified in whom FMAP was measured during superselective angiography. Additional variables analyzed included AVM size, location, nidus border, presence of aneurysms, and arterial supply and venous drainage patterns. The presence of arterial aneurysms was also correlated with site of bleeding on imaging studies. RESULTS: By univariate analysis, exclusively deep venous drainage, periventricular venous drainage, posterior fossa location, and FMAP predicted hemorrhagic presentation. When we used stepwise multiple logistic regression analysis in the cohort that had FMAP measurements (n = 129), only exclusively deep venous drainage (odds ratio [OR], 3.7; 95% confidence interval [CI], 1.4 to 9.8) and FMAP (OR, 1.4 per 10 mm Hg increase; 95% CI, 1.1 to 1.8) were independent predictors (P < 0.01) of hemorrhagic presentation; size, location, and the presence of aneurysms were not independent predictors. There was also no association (P = 0.23) between the presence of arterial aneurysms and subarachnoid hemorrhage. CONCLUSIONS: High arterial input pressure (FMAP) and venous outflow restriction (exclusively deep venous drainage) were the most powerful risk predictors for hemorrhagic AVM presentation. Our findings suggest that high intranidal pressure is more important than factors such as size, location, and the presence of arterial aneurysms in the pathophysiology of AVM hemorrhage.

Adult↗
PubMed1998

The national kidney transplant program in Norway still results in unchanged waiting lists.

1. Of 2,670 patients starting renal replacement therapy for end-stage renal disease in Norway from 1989-1997, 76% were candidates for transplantation. The annual need for transplantations increased from 47 to 64 grafts PMP as the number of elderly patients increased. The national waiting list has remained almost stable during the period from 1989-1997 at levels of 25-30 PMP, but the dialysis population has increased from 57-105 PMP. 2. A total of 1,681 transplants was performed at an annual rate varying between 38 and 46 grafts PMP. The grafts were procured from LDs in 41% and CDs in 59% of cases. Totally 69% of all patients in need were transplanted and 54% of all patients requiring replacement therapy for end-stage renal disease received a transplant. 3. Graft survival rates in recipients of first LD grafts (n = 641) were 91% and 77% at one and 5 years, respectively. One-year graft survival was 97% in HLA-identical grafts (n = 71), 92% in haploidentical grafts (n = 419), 88% in 2 haplotype-mismatched related grafts (n = 43), and 87% in spousal donor grafts (n = 108). 4. Graft survival rates in recipients of first CD grafts (n = 801) were 84% and 65% at one and 5 years, respectively. The rates were 86% and 74% in younger (n = 557) versus 78% and 46% in older (> 65 years) (n = 244) patients. Death with a functioning graft caused approximately 45% and 75% of all graft losses in younger and older patients, respectively. Cardiovascular disease was the major cause of death. 5. A significant beneficial effect of HLA-DR matching was observed in CD grafts performed after 1989, in particular in patients older than age 65.

Adolescent↗
PubMed1998

rCBF SPECT and the acetazolamide test in the evaluation of dementia.

BACKGROUND: The diagnostic potential of 99mTc-HMPAO following systemic administration of the cerebral vasodilator acetazolamide (acetazolamide test) was evaluated using regional-cerebral-blood-flow (rCBF) SPECT in patients with Alzheimer's disease (AD) or with vascular-type of dementia (VD). METHODS: An initial, high-resolution SPELT study was performed with 99mTc-HMPAO, and after 2 days patients were re-evaluated with 99mTc-HMPAO following systemic administration of acetazolamide. Reconstructed SPELT slices were evaluated visually and semiquantitatively by a semiautomatic rCBF map method. RESULTS: Using 99mTc-HMPAO alone, a bilateral hypoperfusion was found in the temporal and/or parietal regions in 33% (6/18) of VD patients and in 70% (23/33) of AD patients. The vascular reserve capacity, as determined with the acetazolamide test, was not impaired in 22% of the VD patients but in 76% of the AD patients. The differences in the perfusion patterns between VD and AD patients were statistically different (p < 0.01, Fischer's exact test). Of the 6 VD patients with hypoperfusion (bilateral temporal and/or parietal), 4 had a decreased vascular reserve capacity as determined in the acetazolamide test. Decreased reserve capacity was found in only 4 out of 25 patients with AD. CONCLUSIONS: The acetazolamide test is helpful in rCBF SPECT to differentiate VD from AD.

Journal Article↗
PubMed1998

Soluble interleukin-2-receptor levels as a marker of coronary microvascular dysfunction after heart transplantation.

BACKGROUND: Immunologic mechanisms operating in a milieu of nonimmunologic risk factors constitute the principal stimuli that result in progressive cardiac allograft vasculopathy. Interleukin-2 has a central role in the development of cell-mediated immunity and is a key factor in the induction of a complex network of cytokines. On exposure to cytokines, endothelial cells can undergo profound alterations of vasomotor function. In this study we characterized the relationship between coronary microvascular function and soluble interleukin-2 receptor (sIL-2R) levels after human heart transplantation. METHODS: We studied 15 heart transplant recipients after an average follow-up time of 39+/-22 months. We measured coronary artery blood flow in an endothelium-dependent manner with acetylcholine (50 microg) and in an endothelium-independent manner with dipyridamole (0.56 mg/kg) by intracoronary Doppler catheter. Blood samples from the superior vena cava were drawn 3 to 12 months after transplantation (early value) and at time of the coronary artery flow measurement (present value). Coronary artery flow reserve was correlated to sIL-2R levels, which were determined by use of an enzyme-linked immunoabsorbent assay. RESULTS: We found a significant inverse correlation between impaired endothelium-mediated (p = 0.03) but not endothelium-independent relaxation of the coronary microvasculature and elevated sIL-2R levels. In heart transplant recipients without acute rejection or an infection episode, an sIL-2R-level of more than 800 U/ml was defined as a cutpoint, indicating disturbed endothelium-dependent microvascular function. Additionally, there was a conspicuous trend toward an inverse correlation between early elevated sIL-2R-levels and endothelium-dependent microvascular dysfunction (p = 0.06). CONCLUSIONS: The results of this study demonstrate the utility of sIL-2R, an index of immunologic activity, to be used as a marker and predictor of impaired endothelial microvascular function in heart transplant recipients. These observations support the hypothesis that after heart transplantation endothelial dysfunction in the microcirculation is an immunologic phenomenon.

Adult↗
PubMed1998

Can a diagnosis of renal allograft rejection be based on histology alone?

Acute renal allograft rejection is suspected by the clinician when the serum creatinine value increases in a patient for no other particular cause. A renal allograft biopsy may confirm the diagnosis. This report describes 2 patients with stable serum creatinine; however, protocol biopsy showed acute rejection changes according to the Banff criteria. No anti-rejection treatment was started and their graft function remained stable for 6 months. These two cases focus on the fact that renal allograft rejection should first of all be regarded as a clinical diagnosis which could be substantiated by histological findings.

Acute Disease↗
PubMed1998

Diltiazem modulates cyclosporin A induced renal hemodynamic effects but not its effect on plasma endothelin-1.

Cyclosporin A (CsA) has been reported to induce major acute renal hypoperfusion that may be antagonised by calcium channel blockers. The vasoconstrictive peptide endothelin-1 (ET-1) has been proposed as a mediator of CsA induced hypoperfusion. We investigated the acute effects of the new CsA formulation (Sandimmun Neoral) in 8 renal transplant patients on triple immunosuppressive therapy before and following slow-release diltiazem treatment in a dose of 90-120 mg b.i.d for 4 weeks. CsA significantly increased mean arterial blood pressure by 6 +/- 2 mmHg (p < 0.05) during the first 3 h after administration. This effect was abolished by diltiazem treatment, also reducing blood pressure by 12 +/- 3 mmHg (p < 0.05) 3-9 h after administration. CsA administration induced a maximum reduction in renal blood flow of 20 +/- 8% (p < 0.05) 5 h after ingestion and a concomitant reduction in glomerular filtration rate of 18 +/- 7% (p < 0.05). The filtration fraction increased by a maximum of 13 +/- 7% (p < 0.05) after 4 h as did the calculated fractional proximal reabsorption by 14 +/- 4% (p < 0.05). All these acute renal effects were abolished by diltiazem administration. Concurrent with the maximum renal hemodynamic effects, plasma ET-1 was elevated with a peak increase of about 40% 4-5 h after CsA ingestion. Diltiazem treatment had no effect on the increase in plasma ET-1 following CsA administration. These findings suggest that CsA induced acute vasoconstriction and renal hypoperfusion are mediated by ET-1 and that diltiazem treatment abolishes these pharmacodynamic effects of CsA despite persistent increase of plasma ET-1 levels.

Adult↗
PubMed1998

Glipizide treatment of post-transplant diabetes does not interfere with cyclosporine pharmacokinetics in renal allograft recipients.

BACKGROUND: Glipizide is an oral antidiabetic drug that has been used in the treatment of post-transplant diabetes mellitus (PTDM). However, a published case report has indicated a possible interaction of glipizide with cyclosporine (CsA) pharmacokinetics in two renal transplant (tx) patients. The aim of this open prospective study was to investigate whether glipizide interacts with CsA pharmacokinetics in renal tx patients with PTDM. METHODS: Eleven renal tx patients (29-74 years of age) with PTDM who received Sandimmun Neoral as part of their immunosuppressive therapy were investigated. No patients had suffered any significant rise in serum creatinine (20%) from any cause over the last 2 wk before the study. Mean S-creatinine was 137 mumol/L (87-220). The mean CsA dose and whole blood concentration remained unchanged during the study. CsA whole blood concentrations were monitored over 12 h in all patients in random order, both on and off glipizide treatment. Blood samples were drawn immediately before the morning dose of CsA was given (trough) and 0.5, 1, 1.5, 2, 3, 4, 6 and 12 h after administration. RESULTS: Whole blood trough CsA concentration was not altered by glipizide treatment, 256 +/- 76 micrograms/L off and 242 +/- 73 micrograms/L (mean +/- SD) with glipizide coadministration. The area under the curve (AUC) and terminal half-life of CsA remained unchanged with glipizide treatment: 6391 +/- 1483 micrograms/L per h and 7.3 +/- 1.5 h without; and 6279 +/- 1601 micrograms/L per h and 7.1 +/- 1.8 h with glipizide, respectively. No change in the CsA peak concentration (Cmax) was observed: 1507 +/- 406 micrograms/L without and 1469 +/- 538 micrograms/L with glipizide coadministration. CONCLUSION: CsA pharmacokinetics is not significantly altered by glipizide coadministration.

Adult↗
PubMed1997

Glucose intolerance after renal transplantation depends upon prednisolone dose and recipient age.

BACKGROUND: Retrospective studies on the prevalence of posttransplant diabetes mellitus (PTDM) in patients on triple-drug immunosuppressive therapy have shown great dispersity, while the incidence of posttransplant impaired glucose tolerance (IGT) is unknown. The aim of our study was to prospectively examine the incidence of posttransplant glucose intolerance and to assess potential risk factors. METHODS: Glucose intolerance was prospectively examined in 173 consecutive kidney transplant recipients by oral glucose tolerance tests (n=167) or the diagnosis of manifest diabetes mellitus (n=6) at 10 weeks after transplant. RESULTS: We found a high incidence of PTDM (18%) and IGT (31%). Univariate analysis revealed that age, family history of diabetes, HLA-B27 phenotype, DR mismatch, rejection, actual prednisolone dose, total methylprednisolone dose, total steroid dose, cytomegalovirus (CMV) infection, and the use of furosemide were associated with PTDM. Age, prednisolone dose, CMV infection, and the use of beta-blockers were associated with IGT. Gender, body mass index, donor source, and cyclosporine level did not influence glucose tolerance. Prednisolone dose, age, family history of diabetes, CMV infection, and HLA-B27 phenotype were independent predictors of PTDM with the use of multiple stepwise logistic regression analysis. Age, prednisolone dose, and the use of a beta-blocker were associated with IGT in the multivariate model. Both univariate and multivariate linear regression analysis revealed a significant relationship between the 2-hr serum glucose and prednisolone dose. The risk of developing PTDM was 5% per 0.01 mg/kg/day of increase in prednisolone dose. CONCLUSIONS: Increased prednisolone dose and older age are strongly associated with the development of posttransplant glucose intolerance.

Adult↗
PubMed1997

Detection and in situ identification of representatives of a widely distributed new bacterial phylum.

16S rRNA gene libraries were prepared by polymerase chain reaction amplification and cloning from soil samples taken periodically from a field with genetically modified plants. Sequence analyses of the cloned rDNAs indicated that 140 of them clustered apart from known bacterial phyla. Based on 31 full sequences a new phylum could be defined. It includes Holophaga foetida, 'Geothrix fermentans' and Acidobacterium capsulatum as the only cultured species so far. Therefore, this line of descent was named the Holophagal Acidobacterium phylum. About 50 published partial sequences of cloned rDNAs retrieved from soil, freshwater sediments or activated sludge from different continents indicate the occurrence of further representatives of this phylum. Two specific hybridization probes were constructed for members of one of four subclusters. A careful data analysis revealed the importance and problems of identifying and dealing with artefacts such as chimeric structure when defining new phylogenetic groups based mainly upon cloned amplified rDNAs. For the first time, the presence of bacterial cells representing this group could be shown in soil, sediment, activated sludge and lake snow by in situ hybridization.

Bacteria↗
PubMed1997

A comparative investigation of DNA adducts, DNA strand breaks and gene mutations induced by benzo[a]pyrene and (+/-)-anti-benzo[a]pyrene-7,8-diol 9,10-oxide in cultured human cells.

Genotoxic effects of benzo[a]pyrene (BP) and its reactive metabolites (+/-)-anti-benzo[a]pyrene-7,8-diol 9,10-oxide ((+/-)-anti-BPDE) were comparatively investigated in vitro with the permanent human fibroblast cell line MRC5CV1. Induced DNA adducts were measured by 32P-postlabeling, DNA strand breakage was determined by the comet assay and the HPRT gene mutation test was used to detect cytotoxicity and mutagenicity. Treatment of MRC5CV1 cells with S9 mix-activated BP or with (+/-)-anti-BPDE resulted in a concentration-dependent increase in DNA adducts and strand breaks. Genotoxic effects of BP and (+/-)-anti-BPDE were detected by 32P-postlabeling and the comet assay with similar sensitivity. However, under the same experimental conditions, a clear induction of gene mutations was only found after (+/-)-anti-BPDE treatment. The relationship between the induction of primary DNA alterations like DNA strand breaks and DNA adducts and the induction of gene mutations is discussed.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗