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1.
Sci Rep ; 10(1): 12427, 2020 07 24.
Article in English | MEDLINE | ID: mdl-32709969

ABSTRACT

Based on infrared spectral characteristics, six archeological sample sets of charcoals from German (5) and Brazilian (1) sites, covering the time span from the nineteenth century CE to 3950 BCE, were compared to a chronological (present to the fifteenth century BCE) series of Austrian charcoals. A typical chronological trend of several bands (stretch vibrations: O-C-O of carboxylates at 1,585-1,565 and 1,385-1,375 cm-1, C-O carboxylic acids at 1,260-1,250 cm-1) that indicate oxidation and subsequently increasing hydrophilicity (O-H stretch vibration at about 3,400 cm-1) was also contained in the archive samples. Three sample sets fit in the typical band development according to their age. For three sample sets this conformity was not observed. Despite the age of two sample sets (3950-2820 BCE), most charcoals were assigned to the Modern Period. Apart from the high degree of carbonization, anaerobic depositional conditions over a longer period of time seem to contribute to the surprising conservation. Non-removable mineral components in charcoals, as observed in a third sample set, strongly influence infrared band intensities and positions of organic compounds. The role of inorganic components in terms of charcoal aging, and the information we can obtain from spectral characteristics in an archeological context, are discussed.

2.
Anaesthesist ; 64(12): 911-926, 2015 Dec.
Article in German | MEDLINE | ID: mdl-26636142

ABSTRACT

The concept of patient safety is more of a presence in modern day medicine than ever before. All measures and processes aiming at preempting and preventing critical incidents and accidents in patient care are collectively grouped under this concept. With the Declaration of Helsinki in 2010 modern anesthesiology has undertaken a fundamental role in the clinical implementation and perioperative clinicians are confronted with a multitude of theories, models, methods and tools targeted at improving or facilitating optimized patient safety. One of the biggest challenges lies in their synergistic combination to create a functioning concept for perioperative risk management while also incorporating individual strengths and weaknesses. The aim of the present paper is to provide a structured overview of the various components presently available for increasing perioperative patient safety.

3.
Science ; 341(6144): 372-6, 2013 Jul 26.
Article in English | MEDLINE | ID: mdl-23888035

ABSTRACT

Ultrathin passive films effectively prevent the chemical attack of stainless steel grades in corrosive environments; their stability depends on the interplay between structure and chemistry of the constituents iron, chromium, and molybdenum (Fe-Cr-Mo). Carbon (C), and eventually boron (B), are also important constituents of steels, although in small quantities. In particular, nanoscale inhomogeneities along the surface can have an impact on material failure but are still poorly understood. Addressing a stainless-type glass-forming Fe50Cr15Mo14C15B6 alloy and using a combination of complementary high-resolution analytical techniques, we relate near-atomistic insights into increasingly inhomogeneous nanostructures with time- and element-resolved dissolution behavior. The progressive elemental partitioning on the nanoscale determines the degree of passivation. A detrimental transition from Cr-controlled passivity to Mo-controlled breakdown is dissected atom by atom, demonstrating the importance of nanoscale knowledge for understanding corrosion.

4.
Strahlenther Onkol ; 189(6): 486-94, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23636349

ABSTRACT

PURPOSE: To report on chronic adverse events (CAE) and quality of life (QOL) after radiochemotherapy (RCT) in patients with anal cancer (AC). PATIENTS AND METHODS: Of 83 patients who had received RCT at our department between 1988 and 2011, 51 accepted the invitation to participate in this QOL study. CAE were evaluated using the Common Terminology Criteria for Adverse Events (CTCAE) v. 4.0 and QOL was assessed with the Functional Assessment of Cancer Therapy-Colorectal (FACT-C) questionnaire. RESULTS: CAE could be evaluated in 49 patients. There was a tendency toward a higher rate of grade 3 CAE in female patients, i.e. 18 out of 37 (49 %) vs. 2 out of 12 (17 %) male patients (p = 0.089). The most common grade 3 CAE were dyspareunia and vaginal symptoms (itching, burning and dryness) in 35 and 22 % of female patients, respectively, followed by stool incontinence in 13 % of all patients (6 out of 49). Both FACT-C and CAE information were available for 42 patients, allowing evaluation of the impact of CAE on QOL. The median total FACT-C score was 110 (40-132) out of a possible maximum of 136. The absence of grade 3 CAE (115 vs. 94, p = 0.001); an interval of ≥ 67 months after the end of the treatment (111 vs. 107, p = 0.010), no stool incontinence vs. grade 3 stool incontinence (111 vs. 74, p = 0.009), higher education (114 vs. 107, p = 0.013) and no dyspareunia vs. grade 3 dyspareunia (116 vs. 93, p = 0.012) were significantly associated with a higher median FACT-C score. CONCLUSION: The majority of AC patients treated with RCT have acceptable overall QOL scores, which are comparable to those of the normal population. Patients with grade 3 CAE-particularly dyspareunia and fecal incontinence-have a poorer QOL compared to patients without CAE. In order to improve long-term QOL, future strategies might aim at a reduction in dose to the genitalia and more intensive patient support measures.


Subject(s)
Anus Neoplasms/therapy , Chemoradiotherapy/adverse effects , Quality of Life/psychology , Aged , Aged, 80 and over , Anus Neoplasms/pathology , Chemoradiotherapy/methods , Chemoradiotherapy/psychology , Dyspareunia/etiology , Fecal Incontinence/etiology , Female , Follow-Up Studies , Germany , Humans , Male , Middle Aged , Radiation Injuries/etiology , Rectum/radiation effects , Urogenital System/radiation effects , Vagina/radiation effects
5.
J Perinatol ; 33(5): 341-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23047423

ABSTRACT

OBJECTIVE: To investigate whether single nucleotide polymorphisms (SNPs) in genes encoding the Toll-like receptor (TLR) signaling pathway modulate susceptibility to preterm birth (PTB). STUDY DESIGN: Prospective case-control study examining the contribution of nine TLR SNPs to PTB (<37 weeks) and PTB <32 weeks. Genotyping was done on neonatal blood using a multiplexed single-base extension assay. Chi-square test, Fischer's exact test and classification trees were used for data analysis. RESULT: Preterm infants (n=177) were more likely to be African American (P=0.02), and were more likely to be born to mothers who smoked (P=0.007), had pregnancy-induced hypertension (PIH; P=0.002) and placental abruption (P=0.0004) when compared with term infants (n=146). The TLR2, TLR4, TLR5, TLR9, nuclear factor-kappa B1 (NFκB1), NFκBIA and IRAK1 variants were not associated with PTB whereas the TIR domain receptor-associated protein (TIRAP) variant was more prevalent in term infants when compared with preterm infants born <32 weeks (P=0.004). PTB <32 weeks was more prevalent in infants without the TIRAP variant whose mothers had PIH and did not smoke (P=0.001). Presence of the TIRAP variant protected against PTB <32 weeks (P=0.015) in Caucasian infants. CONCLUSION: In our study, a TLR pathway adapter variant (TIRAP (rs8177374)) protected against PTB<32 weeks, supporting our hypothesis that genetic variation in the innate immune signaling pathway contributes to altered risk of PTB.


Subject(s)
Membrane Glycoproteins/genetics , Premature Birth/genetics , Receptors, Interleukin-1/genetics , Toll-Like Receptors/genetics , Black or African American/genetics , Case-Control Studies , Female , Genotype , Humans , Infant, Newborn , Male , Polymorphism, Single Nucleotide , Pregnancy , Signal Transduction/genetics , White People/genetics
6.
Strahlenther Onkol ; 189(1): 18-25, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23149618

ABSTRACT

PURPOSE: To report the efficacy and toxicity of radio(chemo)therapy (RCT) in the management of squamous cell anal carcinoma (SQ-AC) and to evaluate the prognostic factors influencing the outcomes. PATIENTS AND METHODS: A consecutive cohort of 138 patients with cT1-4, cN0-3, cM0 SQ-AC were treated with RCT between 1988 and 2011 at our department. Median follow-up time for surviving patients from the start of RCT was 98 months (range, 1-236 months). Patients were treated with a median radiation dose of 56 Gy (range, 4-61 Gy). Concurrent chemotherapy was administered to 119 patients (86%). RESULTS: The survival rates at 2, 5, and 10 years were 88 ± 3, 82 ± 4, and 59 ± 6%, respectively, with a median overall survival (OS) of 167 months. The cumulative incidence for local recurrence at 2 and 5 years was 8 ± 2 and 11 ± 3%, respectively. The median disease-free survival (DFS) and colostomy-free survival (CFS) times were 132 and 135 months, respectively. In 19 patients (14%), a distant metastasis was diagnosed after a median time of 19 months. In the multivariate analysis, UICC (International Union Against Cancer) stage I-II, female gender, Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and good/moderate histologic differentiation (G1-2) were significantly associated with a better OS, DFS, and CFS. Conformal radiotherapy planning techniques were significantly associated with a lower cumulative incidence of local recurrence (11 ± 3% vs. 38 ± 19% at 5 years, p = 0.006). A higher radiation dose beyond 54 Gy was not associated with an improvement in outcome, neither for smaller-(T1/T2) nor for larger tumors (T3/T4). CONCLUSION: RCT leads to excellent outcomes-especially in patients with stage I/II and G1/G2 tumors-with acceptable toxicity. The probable advantages of high-dose radiotherapy should be considered carefully against the risk of a higher rate of toxicity. Future studies are needed to investigate the role of a more intensified (systemic) treatment for patients with unfavorable prognostic factors such as T3/T4, N+, and/or poor cell differentiation.


Subject(s)
Anus Neoplasms/drug therapy , Anus Neoplasms/radiotherapy , Adult , Aged , Aged, 80 and over , Anus Neoplasms/mortality , Anus Neoplasms/pathology , Chemotherapy, Adjuvant , Colonoscopy , Combined Modality Therapy , Disease Progression , Disease-Free Survival , Female , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Staging , Prognosis , Radiotherapy/methods , Radiotherapy Dosage , Sex Factors
7.
Strahlenther Onkol ; 188(6): 464-70, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22349634

ABSTRACT

PURPOSE: The goal of this work was to analyze the response rate and outcome of patients with stage I-III follicular lymphoma (FL) treated with radiotherapy (RT) alone. PATIENTS AND METHODS: The records of 50 consecutive patients with stage I-III FL treated with RT alone at our department from 1988-2009 were analyzed. The median age was 60 years (range 32-80 years) with a median follow-up duration of 8 years (range 4-11 years). Clinical staging was performed according to the Ann Arbor system. Stage I: 30 patients (60%), stage II: 15 patients (30%), stage III: 5 patients (10%). Thirty-two patients (64%) presented with nodal disease, 14 patients (28%) presented with disease in extranodal sites, and 4 patients (8%) had nodal and extranodal involvement. The RT field encompassed only the involved Ann Arbor nodal regions (involved-field RT) in 26 patients (52%), mantle and whole abdominopelvic fields in 6 patients (12%), mantle field in 10 patients (20%), whole abdominopelvic fields in 5 patients (10%), and a so-called mini-mantle in 3 patients (6%). The total RT dose ranged from 26-56 Gy (median 40 Gy) in daily fractions of 1.2-2.5 Gy. RESULTS: Complete remission (CR) and partial remission (PR) were observed in 39 (76%) and 9 (20%) patients, respectively. Only 2 of 8 patients (25%) with tumor bulk > 5 cm reached CR, whereas 37 of 42 patients (88%) with a maximum lymphoma diameter < 5 cm achieved CR (p = 0.0001). The median overall survival (OS) and median event-free survival (EFS) were 18 years (CI 95% 10-26 years) and 7 years (6-8 years), respectively. The 2-, 5-, and 10-year OS were 96 ± 3%, 90 ± 5%, and 70 ± 9%, respectively. The 2-, 5-, and 10-year EFS were 90 ± 5%, 70 ± 7%, and 38 ± 9%, respectively. Fifteen patients developed a recurrence outside the radiation field (30%) and 4 patients developed an in-field recurrence (8%). All in-field recurrences were observed in regions without clinical (macroscopic) involvement, which were irradiated with a dose of ≤ 26 Gy. Pretreatment maximum lymphoma diameter < 5 cm (p = 0.039) and complete remission after RT (p = 0.021) were significantly associated with a better OS in the univariate analysis. CONCLUSION: RT is a curative option in the treatment of limited stage FL. If RT of microscopically uninvolved area is necessary, a reduction in the radiation dose should be carefully weighed against the risk of in-field recurrences.


Subject(s)
Lymphoma, Follicular/radiotherapy , Adult , Aged , Aged, 80 and over , Disease-Free Survival , Female , Follow-Up Studies , Germany , Humans , Lymph Nodes/pathology , Lymphoma, Follicular/mortality , Lymphoma, Follicular/pathology , Male , Middle Aged , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Staging , Retrospective Studies
8.
Eur Radiol ; 13(4): 763-70, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12664115

ABSTRACT

Based on a previous report [9] on alterations of membrane phosphorus metabolism in asymptomatic family members of schizophrenic patients, the aim of the present study was to extend and improve the evaluation and data processing of (31)P spectroscopic data obtained from a larger study population by including an analysis of the broad spectral component (BC) of membrane phospholipids (PL). Eighteen children and siblings of patients with schizophrenia and a gender- and age-matched control group of 18 healthy subjects without familial schizophrenia were investigated with phosphorus magnetic resonance spectroscopy ((31)P-MRS) by using image selected in vivo spectroscopy (ISIS) in the dorsolateral prefrontal regions (DLPFR) of the brain. Spectral analysis was performed by using both the full and truncated FID to estimate metabolic peak ratios of different (31)P metabolites and the intensity and linewidth of the broad component. A significantly higher PDE level (p<0.01) and increased linewidth of the PDE components were observed for the high-risk group compared with the control group (p=0.02). No significant differences were observed for PME as well as for other (31)P-metabolites. No differences were observed between the left and right hemispheres for different normalised (31)P-metabolic levels. Decreased intensities (p=0.03) and smaller linewidths (p=0.01) were obtained for the broad component in the high-risk group. Impairments of membrane metabolism that are typical for schizophrenic patients are partially observed in adolescent asymptomatic family members of schizophrenics, including increased levels of low molecular PDE compounds indicating increased membrane degradation processes, no changes for PME, and decreased intensities and linewidths of the BC indicating changes in the composition and fluidity of membrane phospholipids. Despite limitations to completely suppress fast-relaxing components by dismissing initial FID data points, the spectroscopic results indicate additional changes in the membrane metabolism of high-risk subjects beyond changes of synthesis and degradation.


Subject(s)
Brain/metabolism , Magnetic Resonance Spectroscopy , Schizophrenia/genetics , Adolescent , Brain Chemistry , Case-Control Studies , Child , Female , Humans , Male , Phospholipids/metabolism , Phosphorus/metabolism , Schizophrenia/metabolism
9.
Rofo ; 175(1): 75-82, 2003 Jan.
Article in German | MEDLINE | ID: mdl-12525985

ABSTRACT

PURPOSE: To investigate whether 31 P-MR spectroscopy can detect reduced concentrations of high-energy phosphates, like PCr and NTP, caused by decreased metabolic activity in the brain of patients with anorexia nervosa (AN) and, furthermore, whether any impairment of the cerebral membrane metabolism can be derived from the spectra. MATERIAL AND METHODS: 10 female patients, age range 12 - 20 years and mean BMI (body mass index) of 14.8 +/- 1.6 kg/m 2, with clinically diagnosed AN (ICD-10, F50.0) and 10 healthy control subjects, age range 12 - 21 years and mean BMI 19.0 +/- 2.1 kg/m 2, without nutritional disturbances: were investigated. 31P-MR spectroscopy was performed with a 1.5 T MRI unit using single volume selection in the frontal/prefrontal region of brain. Relative metabolic concentrations were quantified by normalizing the peak areas of the metabolites with the total area of the complete phosphorous spectrum, P tot, as well as with the peak area of beta-NTP. RESULTS: Significant differences between the two groups were observed for the metabolic ratios PDE/P tot, PDE/beta-NTP and alpha-NTP/P tot which were lower in the patient group except for alpha-NTP/P tot. These ratios also revealed a statistically significant correlation with the BMI (r PDE/Ptot = 0.747, r PDE/beta-NTP = 0.57, r alpha-NTP/Ptot = -0.56; p

Subject(s)
Anorexia Nervosa/metabolism , Brain/metabolism , Magnetic Resonance Spectroscopy , Phosphates/metabolism , Adolescent , Adult , Anorexia Nervosa/diagnosis , Body Mass Index , Child , Confidence Intervals , Data Interpretation, Statistical , Energy Metabolism , Esters/metabolism , Female , Fourier Analysis , Frontal Lobe/metabolism , Humans , Magnetic Resonance Spectroscopy/methods , Models, Theoretical , Phosphocreatine/metabolism , Polyphosphates/metabolism , Software , Weight Loss
10.
Am J Psychiatry ; 158(6): 958-60, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11384908

ABSTRACT

OBJECTIVE: Most phosphorus-31 magnetic resonance spectroscopy ((31)P-MRS) studies have described measures of lower membrane anabolism or greater catabolism in the frontal lobes of patients with schizophrenia. The purpose of the present study was to evaluate whether these findings can also be detected in young subjects at genetic risk for schizophrenia. METHOD: Fourteen children and siblings of patients with schizophrenia (mean age=16.7 years) and 14 comparison subjects (mean age=16.9 years) were included in a (31)P-MRS study of the frontal lobe. RESULTS: The high-risk subjects had significantly lower mean ratios of phosphomonoesters to phosphodiesters (0.25 versus 0.31) and higher mean phosphodiester values (37.59% versus 34.87%) than comparison subjects. CONCLUSIONS: These findings suggest greater phospholipid breakdown even in young first-degree relatives of patients with schizophrenia. This suggestion is discussed with respect to the membrane phospholipid hypothesis of schizophrenia.


Subject(s)
Brain/metabolism , Family , Phosphates/metabolism , Schizophrenia/diagnosis , Schizophrenia/metabolism , Adolescent , Brain Chemistry/genetics , Female , Genetic Predisposition to Disease , Humans , Magnetic Resonance Spectroscopy/statistics & numerical data , Male , Phosphates/chemistry , Phosphocreatine/metabolism , Phospholipids/metabolism , Phosphorus Isotopes , Schizophrenia/genetics
11.
Z Kinder Jugendpsychiatr Psychother ; 29(1): 50-8, 2001 Feb.
Article in German | MEDLINE | ID: mdl-11234552

ABSTRACT

In recent years neurobiological research on the etiology of schizophrenia has became increasingly important. In terms of a vulnerability-stress model, structural and functional cerebral alterations in schizophrenics and subjects with a genetic risk for schizophrenia are presented together with hypotheses for disturbances of neurodevelopment or neurodegeneration developed from these implications. A detailed description follows of a neurobiochemical paradigm on the disturbance of metabolism of membrane-phospholipids. 31Phosphorous Magnetic Resonance Spectroscopy allows the detection of indicators of this possible endo-phenotype. The possibilities and limitations of this method are explained, as are findings up to the present. Finally, it is discussed that specific pre-, peri- and postnatal influences on the cerebral metabolism of lipids, and thus on cerebral development, may be related to structural and functional cerebral changes in schizophrenia.


Subject(s)
Brain/metabolism , Magnetic Resonance Spectroscopy/methods , Membrane Lipids/metabolism , Phosphorus Isotopes , Schizophrenia/metabolism , Biomarkers , Brain/diagnostic imaging , Humans , Models, Neurological , Phospholipids/metabolism , Radionuclide Imaging , Risk Factors , Schizophrenia/diagnostic imaging , Schizophrenia/physiopathology
12.
Br J Anaesth ; 84(3): 396-8, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10793603

ABSTRACT

Activation of the renin-angiotensin system during cardiopulmonary bypass (CPB) may be involved in early postoperative hypertension after coronary artery bypass grafting (CABG). As hypertensive episodes may be deleterious in the immediate postoperative period, we have assessed the effects of prophylactic treatment with the angiotensin-converting enzyme inhibitor quinaprilat in an open study. During steady state CPB, patients received quinaprilat 0.02 mg kg-1 (group A, n = 10), quinaprilat 0.04 mg kg-1 (group B, n = 10) or saline solution (group C, n = 10) as an i.v. bolus dose. Sodium nitroprusside (SNP) was given after operation when systolic arterial pressure was > 150 mm Hg. Requirements for SNP 1 h after arrival in the ICU were significantly less in groups A (two of 10) and B (two of 10) than in group C (eight of 10). Also, patients in group C had a greater systolic arterial pressure compared with groups A and B. There were no significant differences between groups in diastolic arterial pressure, heart rate, cardiac index or cardiac filling pressures. We conclude that quinaprilat can be used during CABG to reduce the incidence of postoperative hypertension. Further studies of the efficacy and safety of this technique are necessary.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Coronary Artery Bypass , Hypertension/prevention & control , Postoperative Complications/prevention & control , Tetrahydroisoquinolines , Hemodynamics/drug effects , Humans , Intraoperative Care/methods , Isoquinolines/therapeutic use , Prospective Studies
13.
World J Surg ; 20(7): 758-60; discussion 761, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8678947

ABSTRACT

Using the transperitoneal, laparoscopic approach, we performed 67 successful adrenalectomies between June 1993 and July 1995 at Greenslopes Hospital, Brisbane. There were 30 women and 37 men. Syndromes of primary adrenal hormone overproduction--primary aldosteronism (n = 52), pheochromocytoma (n = 6), and hypercortisolism (n = 1)--were present in 59 patients and apparently nonfunctioning adrenal tumors (of which one was malignant) in 8 patients. There was a significant difference in the time of operation between patients weighing < 80 kg and those weighing > 80 kg. Operations on males were slower than those on females, possibly explained by males being significantly heavier. Left-sided tumors outnumbered right-sided tumors; removal of right-sided adrenals took, on average, longer, but this difference was not significant.


Subject(s)
Adrenalectomy , Laparoscopy , Adrenal Gland Neoplasms/surgery , Adrenal Glands/pathology , Adrenalectomy/adverse effects , Adrenalectomy/instrumentation , Adrenalectomy/methods , Adrenocortical Hyperfunction/surgery , Australia , Body Weight , Female , Humans , Hyperaldosteronism/surgery , Laparoscopes , Laparoscopy/adverse effects , Laparoscopy/methods , Male , Pheochromocytoma/surgery , Sex Factors , Time Factors , Treatment Outcome
14.
Clin Exp Pharmacol Physiol ; 23(6-7): 582-3, 1996.
Article in English | MEDLINE | ID: mdl-8800591

ABSTRACT

1. Mutations of the p53 tumour suppressor gene are relatively common in the aetiology of a wide spectrum of tumour types, both sporadic and familial. 2. The majority of mutations of the p53 gene are reported to be in the highly conserved region of exons 5-8. 3. Alterations in exons 4, 5 and 7 of the p53 gene in patients with functional adrenal tumours, including aldosterone-producing adenomas, have recently been described. 4. In the present study PCR-SSCP was used to examine the exons 4-9 of the p53 gene in paired peripheral blood leucocyte and tumour DNA in a variety of adrenal tumours, including aldosterone-producing carcinoma and adenoma (both familial and sporadic), phaeochromocytoma and incidentaloma. 5. No evidence was found for mutations in exons 4-9 of the p53 gene in these varieties of adrenal tumours.


Subject(s)
Adrenal Gland Neoplasms/genetics , Genes, p53/genetics , Aldosterone/biosynthesis , DNA, Neoplasm/analysis , DNA, Neoplasm/isolation & purification , Exons/physiology , Humans , Lymphocytes/chemistry , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational
15.
Clin Exp Pharmacol Physiol ; 23(6-7): 584-6, 1996.
Article in English | MEDLINE | ID: mdl-8800592

ABSTRACT

1. Aldosterone-producing adenomas (APA) of the adrenal gland may be responsive or un-responsive to the renin-angiotensin system. 2. We have described increased expression of renin mRNA in angiotensin-responsive aldosterone-producing adenomas (AII-R-APA) compared with angiotensin-un-responsive aldosterone-producing adenomas (AII-U-APA) and significantly different allelic frequencies of the BglI, TaqI and HinfI restriction fragment length polymorphisms of the renin gene between the two groups. 3. An area including the 5' flanking region -500 bp from exon 1, exon 1 and intron A contained no gross insertions or deletions when studied by a long polymerase chain reaction technique. 4. In the present study, polymerase chain reaction-single strand conformation polymorphism analysis (PCR-SSCP) revealed no single base pair alteration in the proximal promoter region (-600 bp to transcription start) of the renin gene in patients with APA (either AII-U-APA or AII-R-APA) when compared with normal subjects. 5. Therefore, mutations in this regulatory region do not appear to explain the different levels of renin gene expression observed in these two subtypes of APA.


Subject(s)
Adenoma/genetics , Adenoma/metabolism , Adrenal Gland Neoplasms/genetics , Adrenal Gland Neoplasms/metabolism , Aldosterone/biosynthesis , Promoter Regions, Genetic/genetics , Renin/genetics , Adult , Aged , DNA Probes , Female , Humans , Leukocytes/metabolism , Male , Middle Aged , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational
16.
J Hypertens ; 13(12 Pt 2): 1610-3, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8903619

ABSTRACT

AIM: Since detection of familial hyperaldosteronism type I (glucocorticoid-suppressible hyperaldosteronism) allows specific treatment of hypertension with dexamethasone, we compared clinical, biochemical and genetic approaches to detection. PATIENTS AND METHODS: We studied 22 affected patients, 21 from a single, large family and an additional adopted male. Plasma aldosterone, plasma renin activity and urinary 18-oxo-cortisol were measured by radioimmunoassay. The hybrid gene was demonstrated using either Southern blotting or a long polymerase chain reaction technique. RESULTS: Thirteen out of 22 (59%) patients with familial hyperaldosteronism type I, but only four out of 12 (33%) under 20 years of age, were hypertensive. Plasma potassium and aldosterone were each normal in 20 out of 22 (91%), and unhelpful in diagnosis. Plasma renin activity, the aldosterone: plasma renin activity ratio and 18-oxo-cortisol were more sensitive, being abnormal in 20 out of 22 (91%), 19 out of 22 (86%) and 20 out of 20 (100%) patients, respectively. Aldosterone was unresponsive (<50% rise) to 2 h of upright posture following overnight recumbency in 15 out of 15 (100%) patients studied, and to angiotensin II infusion (2 ng/kg per min for 1 h) in 14 out of 14 patients (100%). Whereas all the abovementioned abnormalities are also characteristic of angiotensin II-unresponsive aldosterone-producing adenoma, marked aldosterone suppression following 4 days of dexamethasone (0.5 mg every 6 h) was sensitive and specific for familial hyperaldosteronism type I (n = 11). The hybrid gene was detectable in peripheral blood leucocyte DNA in all 22 affected patients by Southern blotting, and by a faster, long polymerase chain reaction method developed in our laboratory, both methods requiring only a single blood collection. CONCLUSIONS: Should studies in other families confirm its universal applicability, long polymerase chain reaction should prove to be the most practical means of detecting familial hyperaldosteronism type I in laboratories equipped with this technique.


Subject(s)
Aldosterone/blood , DNA/analysis , Hydrocortisone/analogs & derivatives , Hyperaldosteronism/diagnosis , Hypertension/diagnosis , Leukocytes/metabolism , Potassium/blood , Adolescent , Adult , Aged , Base Sequence , Blood Pressure , Blotting, Southern , Child , Female , Humans , Hydrocortisone/urine , Hyperaldosteronism/complications , Hyperaldosteronism/metabolism , Hypertension/complications , Hypertension/metabolism , Male , Middle Aged , Molecular Sequence Data , Polymerase Chain Reaction
17.
Hypertension ; 26(4): 624-7, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7558222

ABSTRACT

We investigated renal and peripheral forearm extraction of atrial natriuretic peptide in patients with primary aldosteronism to determine whether alterations in extraction may contribute to the elevated levels of circulating atrial natriuretic peptide observed in primary aldosteronism. We obtained simultaneous venous blood samples from the left renal vein and a peripheral vein and from the radial artery in 28 patients with primary aldosteronism and 10 patients with essential hypertension. Renal extraction of atrial natriuretic peptide was significantly (P < .001) reduced (40 +/- 2%) in primary aldosteronism compared with essential hypertensive patients (62 +/- 3%). Peripheral forearm extraction was also reduced (P < .01) in primary aldosteronism compared with essential hypertensive patients (24 +/- 3% versus 38 +/- 4%). These findings are consistent with widespread downregulation of atrial natriuretic peptide receptors in primary aldosteronism. Consistent with reports that marked reduction in glomerular filtration rate is required before the renal extraction of atrial natriuretic peptide is reduced, no significant relationship between renal extraction of atrial natriuretic peptide and plasma creatinine was seen in primary aldosteronism or essential hypertension. Although the major regulators of atrial natriuretic peptide secretion in primary aldosteronism are presumably alterations in arterial blood pressure and plasma volume, reduced renal and peripheral extraction of atrial natriuretic peptide in primary aldosteronism may also contribute significantly to the elevated circulating levels observed.


Subject(s)
Atrial Natriuretic Factor/metabolism , Hyperaldosteronism/metabolism , Kidney/metabolism , Arteries , Forearm/blood supply , Humans , Renal Circulation , Veins
18.
Biochem Biophys Res Commun ; 215(1): 172-8, 1995 Oct 04.
Article in English | MEDLINE | ID: mdl-7575587

ABSTRACT

Previous studies have shown a significant association between allelic frequencies at the ANP gene locus and aldosterone responsiveness to angiotensin in aldosterone-producing adenoma (APA). We searched for any gross insertions or deletions in the ANP gene in APA and any associations between allelic frequencies at the Hpa II and Sca I RFLP sites within the ANP gene and angiotensin-responsive and unresponsive APA and normal subjects. We also searched for possible point mutations in the promoter region of the ANP gene (-595 to transcription start site) in peripheral blood and tumor DNA from 59 patients with APA and in peripheral blood DNA from 39 normal subjects by polymerase chain reaction and single strand conformation polymorphism (PCR-SSCP) analysis. No large alterations in the ANP gene were observed, and no difference in allelic frequencies at the RFLP sites were seen between the two tumor subtypes, angiotensin-responsive and angiotensin-unresponsive APA, or between the APA group and normal subjects. SSCP analysis, however, did reveal mutations in the promoter region of the ANP gene (-375 to -595) in both peripheral blood and tumor DNA from 8 of 59 (14%) patients with APA, compared with only one of 39 normal controls (2.6%). This study suggests that alterations in the proximal promoter region of the ANP gene in APA may be important in the regulation of ANP transcription and may be involved in the underlying pathophysiology of aldosterone-producing adenoma in at least some patients.


Subject(s)
Adenoma/metabolism , Adrenal Cortex Neoplasms/metabolism , Aldosterone/biosynthesis , Atrial Natriuretic Factor/genetics , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Promoter Regions, Genetic , Base Sequence , DNA/blood , DNA/chemistry , Deoxyribonucleases, Type II Site-Specific , Humans , Molecular Sequence Data , Mutation , Polymorphism, Restriction Fragment Length
19.
Blood Press ; 4(5): 300-6, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8535552

ABSTRACT

The effects on blood pressure (BP) and heart rate (HR), at rest and during bicycle exercise, of the vascular selective calcium antagonist felodipine, the cardio-selective beta-blocker metoprolol, and of the two drugs in combination, were assessed in a double-blind, three-way cross-over study comprising 23 patients with essential, mild to moderate hypertension. All three treatment regimens were given to each patient in randomised order for 4 weeks after a 4 week placebo run-in period. Felodipine 10-20 mg daily, metoprolol 100-200 mg daily and the combination of felodipine 10-20 mg plus metoprolol 100 mg daily were all effective antihypertensive treatments both at rest and during exercise. The two drugs seemed to have additive effects and the effect on BP of the combination was greater than that of either drug given as monotherapy. The mean sitting BP was 148/103 mmHg at randomisation, after 4 weeks of placebo treatment, and 134/88, 134/94 and 121/84 mmHg, respectively, after 4 weeks' treatment with felodipine, metoprolol and the combination. Maximal exercise capacity was similar irrespective of treatment regimen, and the normal response to exercise BP and HR was maintained during all active treatments. Changes observed in volume regulatory hormones (PRA, aldosterone and ANP) were consistent with a direct tubular natriuretic-diuretic effect of felodipine and of beta-blocker attenuated release of renin. All treatment regimens were well tolerated and adverse events reported were usually mild and transient.


Subject(s)
Blood Pressure/drug effects , Exercise , Felodipine/therapeutic use , Hypertension/physiopathology , Metoprolol/therapeutic use , Adult , Aged , Aldosterone/blood , Atrial Natriuretic Factor/blood , Blood Pressure/physiology , Double-Blind Method , Drug Therapy, Combination , Exercise Test , Felodipine/adverse effects , Female , Humans , Hypertension/drug therapy , Male , Metoprolol/adverse effects , Middle Aged , Renin/blood
20.
Clin Exp Pharmacol Physiol ; 22(6-7): 444-6, 1995.
Article in English | MEDLINE | ID: mdl-8582097

ABSTRACT

1. Early diagnosis of Familial Hyperaldosteronism Type I (FH-I, glucocorticoid-suppressible hyperaldosteronism) in asymptomatic, affected individuals is essential if death from stroke is to be prevented. 2. In 21 patients with FH-I (presence of the causative hybrid 11 beta-hydroxylase/aldosterone synthase gene confirmed by Southern blot testing), various biochemical parameters were compared as possible screening tests. Hypokalaemia and elevated plasma aldosterone each detected only two (10%) of the affected individuals. 3. Plasma renin activity 19 (90%) and aldosterone/renin ratio 18 (86%) were more reliable but not free from false negatives. 4. Levels of the urinary 'hybrid' steroid, 18-oxocortisol, were elevated (P < 0.01) in all 15 patients tested (138.2 +/- 17.4 micrograms/g creatinine, range 41.6 +/- 281.0 micrograms/g) with no overlap when compared with 11 normals (9.7 +/- 1.3 micrograms/g, range 2.8-17.4 micrograms/g). 5. We conclude that measurement of urinary 'hybrid' steroids is probably the most rapid and reliable biochemical screening test currently available for FH-I, with confirmation dependent on demonstration of the hybrid gene by genetic techniques.


Subject(s)
Hyperaldosteronism/genetics , Adult , Aldosterone/blood , Blotting, Southern , Cytochrome P-450 CYP11B2 , Cytochrome P-450 Enzyme System/genetics , Female , Gene Expression Regulation, Enzymologic/genetics , Humans , Hydrocortisone/analogs & derivatives , Hydrocortisone/urine , Hyperaldosteronism/diagnosis , Hyperaldosteronism/metabolism , Male , Middle Aged , Potassium/blood , Radioimmunoassay , Renin/blood , Steroid 11-beta-Hydroxylase/genetics
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