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1.
J Endocrinol Invest ; 36(7): 485-8, 2013.
Article in English | MEDLINE | ID: mdl-23324400

ABSTRACT

BACKGROUND: Studies from every continent have shown that only around 50% of the patients subjected to thyroid hormone replacement have TSH in the normal range. However, to date, there are no consistent data about Brazil. OBJECTIVES: To evaluate levothyroxine (LT4) replacement treatment in patients with primary hypothyroidism followed in referral centers in Brazil. METHODS: Patients with primary hypothyroidism followed in referral centers (University Hospitals from Universidade Federal do Rio de Janeiro - UFRJ, Unicamp, Universidade Federal do Paraná - UFPR and Universidade Federal do Ceará-UFC) answered a questionnaire that inquired about clinical and biochemical conditions, social- economic status, life quality and clinicians' orientations as well as their understanding about the information given. Serum TSH was checked close to the interview. RESULTS: 2292 consecutive patients met the inclusion criteria. Mean age 51.2 yr and TSH values between 0.4 and 4.0 mUI/l were considered to be within the reference range. Among all patients taking thyroid medication, 42.7% had an abnormal serum TSH (28.3% were undertreated and 14.4% were overtreated). Approximately all patients (99%) took LT4 in the morning but less than 30 min before breakfast (85.4%). Regarding the clinicians' orientations: 97.5% of the patients were instructed to take the medication daily, and 92.6% to take 30 min before breakfast (92.6%). However, only 52.1% were told not to take LT4 along with other medication. CONCLUSIONS: Our study found that a significant number of patients taking thyroid hormones were not in the therapeutic range. Clinicians should, therefore, consider monitoring patients on thyroid replacement more frequently and being more precise on giving recommendations about the correct use of LT4.


Subject(s)
Hypothyroidism/drug therapy , Thyrotropin/blood , Thyroxine/therapeutic use , Adult , Aged , Brazil , Cross-Sectional Studies , Female , Hormone Replacement Therapy , Humans , Male , Middle Aged , Thyroxine/administration & dosage
2.
J Neurosurg Sci ; 57(1): 69-74, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23584222

ABSTRACT

AIM: The flexible artificial disc may create a system with a biomimetic structure that has the potential to tolerate dynamic motion in a way similar to a normal intervertebral disc over a long period. The objective was to evaluate the mechanical feasibility and clinical and radiological findings with a mono-unit and flexible artificial disc at intermediate-term follow-up. METHODS: Fifty-six patients with degenerative disc disease were selected to participate in the study. They underwent discectomy with a flexible artificial disc with a mean follow-up period of 24.8 months. Outcomes were evaluated with the visual analogue scale (VAS) and Oswestry Disability Index (ODI). Mechanical endurance was evaluated by a dynamic testing. RESULTS: Fifty one-levels and six bi-levels were included in the study (average age 41.8 years). VAS improved from 6.8 ± 2.2 to 1.5 ± 1.7 (P<0.05) and ODI improved from 43.1 ± 10.4 to 18.2 ± 10.2 (P<0.05). Disc height before mechanical testing was 8.9 mm, and decreased to 8.4 mm after six million cycles with no mechanical failure. CONCLUSION: Our results indicate that flexible and mono-unit cervical disc provides favorable mechanical performance and clinical outcomes for at least a relatively intermediate-term follow up period. It is indicated that the flexible cervical disc maintains mobility at the level of the prosthesis that is comparable with preoperative ranges of motion. Further evaluation will be completed once long-term results have been obtained.


Subject(s)
Arthroplasty/standards , Cervical Vertebrae/surgery , Intervertebral Disc Degeneration/surgery , Prostheses and Implants/standards , Prosthesis Implantation/standards , Adult , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/pathology , Disability Evaluation , Follow-Up Studies , Humans , Intervertebral Disc Degeneration/diagnostic imaging , Male , Middle Aged , Postoperative Period , Radiography , Range of Motion, Articular/physiology , Severity of Illness Index , Time Factors , Treatment Outcome , Young Adult
3.
Int J Oral Maxillofac Surg ; 49(10): 1355-1359, 2020 Oct.
Article in English | MEDLINE | ID: mdl-31371154

ABSTRACT

The purpose of this study was to determine whether tooth extraction for patients with ventricular assist devices (VADs) could be performed without interruption of anticoagulant and/or antiplatelet therapy and whether treatment with von Willebrand factor concentrates and desmopressin is required. The study consisted of three groups of patients undergoing oral surgery. The two experimental groups comprised patients with VADs, while the third group included cardiovascular patients without VADs who served as controls. All patients were treated intraoperatively with topical haemostatic agents (oxidized cellulose or collagen). The first group was additionally treated with fibrin glue. All 75 oral surgical procedures were performed under local anaesthesia without sedation. Three of 40 patients in the experimental groups and two of 20 patients in the control group suffered a haemorrhage, with no significant difference in the incidence of haemorrhage between the groups. The findings suggest that dental extraction can be performed without modification of oral anticoagulation or antiplatelet treatments, providing that INR is less than 3.5 on the day of the operation. It can further be hypothesized that an acquired coagulopathy in VAD patients does not influence the bleeding risk in dental extractions, and so the administration of desmopressin and/or von Willebrand factor concentrates is not required.


Subject(s)
Heart-Assist Devices , Hemorrhage , Hemostasis , Humans , Oral Hemorrhage , Tooth Extraction
4.
Breast ; 50: 11-18, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31958661

ABSTRACT

BACKGROUND: Patients with breast cancer (BC) show strong interest in complementary and alternative medicine (CAM), particularly for adverse effects of adjuvant endocrine treatment - e.g., with letrozole. Letrozole often induces myalgia/limb pain and arthralgia, with potential noncompliance and treatment termination. This analysis investigated whether CAM before aromatase inhibitor (AI) therapy is associated with pain development and the intensity of AI-induced musculoskeletal syndrome (AIMSS) during the first year of treatment. PATIENTS AND METHODS: The multicenter phase IV PreFace study evaluated letrozole therapy in postmenopausal, hormone receptor-positive patients with early BC. Patients were asked about CAM use before, 6 months after, and 12 months after treatment started. They recorded pain every month for 1 year in a diary including questions about pain and numeric pain rating scales. Data were analyzed for patients who provided pain information for all time points. RESULTS: Of 1396 patients included, 901 (64.5%) had used CAM before AI treatment. Throughout the observation period, patients with CAM before AI treatment had higher pain values, for both myalgia/limb pain and arthralgia, than non-users. Pain increased significantly in both groups over time, with the largest increase during the first 6 months. No significant difference of pain increase was noted regarding CAM use. CONCLUSIONS: CAM use does not prevent or improve the development of AIMSS. Pain intensity was generally greater in the CAM group. Therefore, because of the risk of non-compliance and treatment discontinuation due to the development of higher pain levels, special attention must be paid to patient education and aftercare in these patients.


Subject(s)
Aromatase Inhibitors/adverse effects , Breast Neoplasms/drug therapy , Complementary Therapies , Letrozole/adverse effects , Musculoskeletal Pain/chemically induced , Aged , Arthralgia/chemically induced , Female , Germany/epidemiology , Humans , Middle Aged , Myalgia/chemically induced , Postmenopause
5.
Science ; 227(4688): 754-6, 1985 Feb 15.
Article in English | MEDLINE | ID: mdl-3969564

ABSTRACT

Lactic acidosis, a clinical syndrome caused by the accumulation of lactic acid, is characterized by lactate concentration in blood greater than 5 mM. Therapy usually consists of intravenous sodium bicarbonate (NaHCO3), but resultant mortality is greater than 60 percent. The metabolic and systemic effects of NaHCO3 therapy of hypoxic lactic acidosis in dogs were studied and compared to the effects of sodium chloride or no therapy. Sodium bicarbonate elevated blood lactate concentrations to a greater extent than did either sodium chloride or no treatment. Despite the infusion of NaHCO3, both arterial pH and bicarbonate concentration decreased by a similar amount in all three groups of dogs. Additional detrimental effects of NaHCO3 were observed on the cardiovascular system, including decreases in cardiac output and blood pressure that were not observed with either sodium chloride or no treatment. Thus there is evidence for a harmful effect of NaHCO3 in the treatment of hypoxic lactic acidosis.


Subject(s)
Acidosis/drug therapy , Bicarbonates/adverse effects , Lactates/blood , Animals , Disease Models, Animal , Dogs , Hemodynamics , Hydrogen-Ion Concentration , Lactates/biosynthesis
6.
Science ; 167(3918): 558-60, 1970 Jan 30.
Article in English | MEDLINE | ID: mdl-17781496

ABSTRACT

Grain size and etching experiments show that the fine lunar material contains large amounts of trapped solar wind particles. Elemental and isotopic compositions of the noble gases in solar material and in the terrestrial atmosphere are significantly different, except for the Ar(36)/ Ar(38) and the Kr isotope ratios. Exposure ages of two rocks and of the fine material are between 380 and 510 x 10(6) years. Feldspar concentrates give K/Ar ages of 3220 and 3300 x 10(6) years, significantly higher than the unseparated rock.

7.
Int J Clin Pract ; 63(4): 583-90, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18803554

ABSTRACT

CONTEXT: High doses of (131)I are usually needed in the treatment of multinodular goitre (MNG) for effective thyroid volume (TV) reduction. Recombinant human thyroid-stimulating hormone (rhTSH) is an adjuvant to enhance (131)I uptake, allowing a decrease in radiation activity and enhancing (131)I efficacy. OBJECTIVE: To evaluate whether rhTSH increases the efficacy of a fixed activity of (131)I for the treatment of MNG. DESIGN: Two-year, observational, placebo-controlled study. SETTING: Patients received 0.1 mg rhTSH (A), 0.005 mg rhTSH (B) or placebo (C). A fixed activity of 1.11 GBq of (131)I was administered 24 h after rhTSH or placebo. PATIENTS: A total of 28 outpatients (26 females and two males) with MNG. MEASUREMENTS: TSH, free T4, T3, thyroglobulin (Tg) and TV. RESULTS: Basal radioactive iodine uptake and TV values were comparable among all groups. After rhTSH or placebo, peak levels of TSH, free T4, T3 and Tg were higher in A than in B or in C (p < 0.05). Hyperthyroidism was observed in A (n = 2), B (n = 6) and C (n = 4). Thyroid enlargement was reported in A (n = 3) and B (n = 6). After 24 months, 10 patients developed hypothyroidism (four in A, three in B and three in C). TV reduction was similar between A and B (37.2 +/- 25.5% vs. 39.3 +/- 27.9%, p = 0.88), but different from the non-significant reduction in C (15.3 +/- 28.3%, p = 0.08). CONCLUSIONS: Followed by 1.11 GBq, a very low dose of 0.005 mg rhTSH was equally safe and effective as 0.1 mg rhTSH. Both doses increased the efficacy of radioiodine. Adverse events were mild, transient and readily treatable.


Subject(s)
Goiter, Nodular/therapy , Iodine Radioisotopes/therapeutic use , Thyrotropin/therapeutic use , Aged , Combined Modality Therapy , Dose-Response Relationship, Radiation , Female , Humans , Iodine Radioisotopes/adverse effects , Male , Middle Aged , Recombinant Proteins/therapeutic use , Thyrotropin/adverse effects , Treatment Outcome
8.
Eur Surg Res ; 42(4): 209-15, 2009.
Article in English | MEDLINE | ID: mdl-19279385

ABSTRACT

Colonic anastomosis healing in hypothyroidism was evaluated. Twenty Wistar rats were separated into two groups: the study group (n = 10), which underwent total thyroidectomy to induce hypothyroidism, and the control group (n = 10). After 10 weeks, hypothyroid status was confirmed by blood tests (p < 0.0001). Three days later, a colonic anastomosis was performed, and the animals were sacrificed 1 week later. The colon containing the anastomosis was resected for bursting strength tests and histological studies. The slides were stained with hematoxylin-eosin and with Sirius red to quantify and classify the collagen. Reduced values were found for the bursting strength test (p = 0.0006) and for collagen density in the experimental group. There was a prevalence of immature type III collagen (p < 0.0001) and a decrease in mature type I collagen (p < 0.0001) in the hypothyroid group.


Subject(s)
Colon/surgery , Hypothyroidism/physiopathology , Wound Healing , Anastomosis, Surgical , Animals , Colon/pathology , Male , Pressure , Rats , Rats, Wistar
9.
Eur J Clin Invest ; 38(10): 721-7, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18837797

ABSTRACT

BACKGROUND: Although the risk of developing dysglycaemia has been investigated in different communities this incidence is poorly studied in patients on maintenance haemodialysis (MHD). MATERIALS AND METHODS: In a multicentre observational cohort study the occurrence of dysglycaemia was assessed in 239 primary normoglycaemic end stage renal disease (ERSD) patients on MHD. Dysglycaemia (fasting blood glucose > 110 mg dL(-1), > 140 mg dL(-1) 2 h after food intake) or diabetes (fasting blood glucose > 126 mg dL(-1) or > 200 mg dL(-1) at any time) were defined according to WHO criteria and cases were compared with age matched controls within the cohort. RESULTS: Dysglycaemia was found in 82 primary normoglycaemic ESRD patients (34%) within 31 months after initiation of MHD. In 31 of these patients type 2 diabetes was diagnosed. When compared with matched control MHD patients differences in body mass index (BMI), HbA1c and postprandial blood glucose were detectable (P < 0.05). Increments in 0.1% of HbA1c were related with 11% higher odds for dysglycaemia (P = 0.002). In a subgroup of 36 primary normoglycaemic MHD patients who developed dysglycaemia event-free survival was 64%, 53%, 31%, 17% and 11% after 1, 2, 3, 4 and 5 years of haemodialysis treatment. CONCLUSION: Onset of dysglycaemia or diabetes is frequent in ESRD patients after onset of chronic haemodialysis. Routine measurement of blood glucose before and after haemodialysis should be implemented as a standard of care during MHD.


Subject(s)
Diabetes Mellitus/etiology , Kidney Failure, Chronic/complications , Renal Dialysis , Aged , Biomarkers/blood , Diabetes Mellitus/blood , Diabetes Mellitus/mortality , Disease Progression , Disease-Free Survival , Female , Glycated Hemoglobin/analysis , Humans , Hyperglycemia/blood , Hyperglycemia/etiology , Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/therapy , Male , Middle Aged , Postprandial Period , Statistics, Nonparametric
10.
Int J Oral Maxillofac Surg ; 37(7): 634-40, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18343095

ABSTRACT

To improve integration between implants and biological tissues, this study compared bone sialoprotein (BSP) as a surface-coating material against the major organic and inorganic components of bone, collagen type I and hydroxyapatite (TICER). The expression of osteocalcin, osteonectin and transforming growth factor ss was evaluated using immunohistochemical staining procedures. The distribution patterns of osteoblasts on the surface of pure titanium with a smooth machined surface and a rough surface (TICER) were determined by image processing using confocal laser scanning microscopy. The results compared to uncoated control materials showed that, at all times investigated, the number of cells on the surface of the TICER and pure titanium samples differed significantly (P<0.1), demonstrating the superiority of TICER over pure titanium in this respect. For pure titanium implants, collagen-precoated surfaces were not beneficial for the attachment of bone-derived cells with the exception of day 3 in vitro (P<0.01). BSP-precoated implant surfaces displayed non-significantly higher numbers of settled cells. BSP-precoated implant surfaces were beneficial for osteoinduction as revealed by osteocalcin and osteonectin expression. BSP precoating of the rough TICER implant surface enhanced the osteoinductive effect much more than did collagen precoating. These results contribute to the consideration of at least two distinct pathways of osseointegration.


Subject(s)
Coated Materials, Biocompatible/chemistry , Collagen Type I/chemistry , Dental Implants , Dental Materials/chemistry , Durapatite/chemistry , Osteoblasts/pathology , Sialoglycoproteins/chemistry , Titanium/chemistry , Adult , Cell Adhesion , Cell Count , Cells, Cultured , Humans , Image Processing, Computer-Assisted , Integrin-Binding Sialoprotein , Male , Microscopy, Confocal , Middle Aged , Osteocalcin/analysis , Osteonectin/analysis , Surface Properties , Time Factors , Transforming Growth Factor beta/analysis
11.
J Clin Invest ; 76(3): 919-23, 1985 Sep.
Article in English | MEDLINE | ID: mdl-4044835

ABSTRACT

The metabolic and systemic effects of dichloroacetate (DCA) in the treatment of hypoxic lactic acidosis were evaluated in the dog and compared with the infusion of equal quantities of volume and sodium. Hypoxic lactic acidosis was induced by ventilating dogs with an hypoxic gas mixture of 8% oxygen and 92% nitrogen, resulting in arterial PO2 of less than 30 mmHg, pH below 7.20, bicarbonate less than 15 mM, and lactate greater than 7 mM. After, the development of hypoxic lactic acidosis dogs were treated for 60 min with either DCA as sodium salt or NaCl at equal infusions of volume and sodium. Dogs treated with DCA showed a significant increase of arterial blood pH and bicarbonate, and steady levels of lactate, whereas NaCl resulted in further declines of blood pH and bicarbonate, and rising blood lactate levels. Overall lactate production decreased during therapy with either regimen, but hepatic lactate extraction increased significantly with DCA, while it remained unchanged with NaCl. Tissue lactate levels in liver and skeletal muscle decreased significantly with DCA treatment but were unchanged with NaCl. Additionally, an increase in muscle intracellular pH was observed only in DCA treated dogs. A possible mechanism for the observed actions of DCA might be related to a significant increase in oxygen delivery to tissues. Such an effect was found with DCA administration, but was not observed with NaCl therapy. In conclusion, DCA therapy in hypoxic lactic acidosis has beneficial systemic effects compared with therapy with NaCl. DCA administration is accompanied by increases of blood pH and bicarbonate, a decrease in lactate production, and enhanced liver lactate extraction, and a lowering of tissue lactate levels.


Subject(s)
Acetates/administration & dosage , Acidosis/blood , Dichloroacetic Acid/administration & dosage , Lactates/blood , Acid-Base Equilibrium/drug effects , Acidosis/drug therapy , Acidosis/metabolism , Animals , Dogs , Female , Hemodynamics/drug effects , Hydrogen-Ion Concentration , Intracellular Fluid/metabolism , Lactates/biosynthesis , Lactates/metabolism , Liver/metabolism , Male , Muscles/metabolism , Oxygen Consumption/drug effects , Sodium Chloride/administration & dosage
12.
J Clin Invest ; 91(2): 397-401, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8432847

ABSTRACT

Patients with terminal renal insufficiency suffer from an increased incidence of atherosclerotic diseases. Elevated plasma concentrations of lipoprotein(a) [Lp(a)] have been established as a genetically controlled risk factor for these diseases. Variable alleles at the apo(a) gene locus determine to a large extent the Lp(a) concentration in the general population. In addition, other genetic and nongenetic factors also contribute to the plasma concentrations of Lp(a). We therefore investigated Apo(a) phenotypes and Lp(a) plasma concentrations in a large group of patients with end-stage renal disease (ESRD) and in a control group. Lp(a) concentrations were significantly elevated in ESRD patients (20.1 +/- 20.3 mg/dl) as compared with the controls (12.1 +/- 15.5 mg/dl, P < 0.001). However, no difference was found in apo(a) isoform frequency between the ESRD group and the controls. Interestingly, only patients with large size apo(a) isoforms exhibited two- to fourfold elevated levels of Lp(a), whereas the small-size isoforms had similar concentrations in ESRD patients and controls. Beside elevated Lp(a) concentrations, ESRD patients had lower levels of plasma cholesterol and apolipoprotein B. These results show that elevated Lp(a) plasma levels might significantly contribute to the risk for atherosclerotic diseases in ESRD. They further indicate that nongenetic factors related to renal insufficiency or other genes beside the apo(a) structural gene locus must be responsible for the high Lp(a) levels.


Subject(s)
Apolipoproteins/chemistry , Kidney Failure, Chronic/blood , Lipoprotein(a)/blood , Adult , Aged , Apolipoproteins B/blood , Apoprotein(a) , Arteriosclerosis/etiology , Cholesterol/blood , Female , Humans , Lipoprotein(a)/genetics , Male , Middle Aged , Phenotype , Polymorphism, Genetic
13.
J Clin Invest ; 94(5): 2045-50, 1994 Nov.
Article in English | MEDLINE | ID: mdl-7962550

ABSTRACT

To elucidate the metabolism of islet amyloid polypeptide (IAPP) with respect to a possible renal elimination we investigated IAPP levels in 20 lean, nondiabetic patients with renal failure maintained on chronic hemodialysis (HD) and in 20 healthy controls. The basal levels of IAPP were significantly higher in uremic patients than in controls (15.1 +/- 3.2 vs. 3.2 +/- 0.2 pM, P < 0.001) suggesting renal excretion of IAPP. To investigate the impact of chronically elevated levels of endogenous IAPP on insulin secretion and insulin sensitivity, a frequently sampled intravenous glucose tolerance test (FSIGT) was performed in a subset of patients on hemodialysis and in age-matched healthy controls (C) and obese patients with normal (NGT) and with impaired glucose tolerance (IGT). Insulin sensitivity index (SI) was 8.7 +/- 1.5 in C (P < 0.05 vs. NGT, P < 0.01 vs. IGT), 5.4 +/- 0.9 in HD (P < 0.05 vs. IGT), 3.1 +/- 1.0 in NGT, and 2.0 +/- 0.5 in IGT. First phase insulin secretion was increased in patients on HD compared with those of several control groups. The results of this study therefore indicate a renal route of metabolism of IAPP. Increased endogenous circulating IAPP levels over a long period of time do not lead to a decrease in insulin release in patients on HD and do not cause the insulin resistance commonly seen in obesity and diabetes. Increased levels of circulating IAPP therefore are not likely to be a pathogenetic factor in the development of non-insulin-dependent diabetes mellitus (NIDDM).


Subject(s)
Amyloid/blood , Insulin/metabolism , Kidney Failure, Chronic/blood , Adult , Diabetes Mellitus, Type 2/etiology , Glucose Tolerance Test , Humans , Insulin Secretion , Islet Amyloid Polypeptide , Middle Aged
14.
Eur J Med Res ; 12(1): 6-12, 2007 Jan 31.
Article in English | MEDLINE | ID: mdl-17363352

ABSTRACT

The interaction between implant material and surrounding tissues is believed to play a fundamental role in implant success. Although bone sialoprotein (BSP) has been found to be osteoinductive when coated onto femoral implants, collagen and fibronectin are the most used compounds for preparation of pre-coated cell culture slides at present. In this study, the support of BSP-, collagen- and fibronectin-coated and non-coated implant material for the development of adult human maxillar bone in vitro was studied and compared. The expression of bone turnover markers like BSP and osteocalcin as well as osteonectin, transforming growth factor beta (TGF-beta) and CD90 during different time periods of cell cultivation (3, 5, 10, 15, 20 and 25 days) was visualized immunohistochemically. The distribution patterns of the cells were examined on a rough surface of the titanium-hydroxyapatite dental implant material TICER and on a total smooth surface of the technical implant material glimmer. Significantly different values were found for glimmer at the 15. and the 20. Div, exclusively, indicating that a smooth surface was more improved than a rough ceramic surface by pre-coatings. The White-test using rankings of the median values gave evidence for BSP-coatings at position 1 followed by collagen. Our experiments were designed to use very low concentrated BSP coating solution with the aim to reduce the healing time with a minimal effort and minimal risks for the patients.


Subject(s)
Coated Materials, Biocompatible/pharmacology , Collagen/pharmacology , Fibronectins/pharmacology , Maxilla/drug effects , Prostheses and Implants , Sialoglycoproteins/pharmacology , Surface Properties/drug effects , Humans , Immunohistochemistry , Integrin-Binding Sialoprotein , Maxilla/cytology , Maxilla/growth & development , Microscopy, Atomic Force , Osteocalcin/metabolism , Osteonectin/metabolism , Time Factors , Transforming Growth Factor beta/metabolism
15.
Biochim Biophys Acta ; 564(2): 225-34, 1979 Sep 27.
Article in English | MEDLINE | ID: mdl-385055

ABSTRACT

Conditions for the ligation with T4 induced DNA ligase of two DNA molecules via their complementary sticky ends have been established which lead preferentially to the formation of hybrid molecules. This is demonstrated with two combinations of parent molecules varying greatly in their relative molecular weights. In one case the intact hybrid molecule could be directly isolated. In addition a DNA dependent quantitative electrophoretic assay for DNA ligase activity is described which does not need a radioactively labeled substrate. The ligation procedure has been shown to be useful in molecular cloning experiments.


Subject(s)
DNA Ligases/metabolism , DNA , Polynucleotide Ligases/metabolism , DNA Ligases/isolation & purification , DNA Restriction Enzymes , Escherichia coli/enzymology , Kinetics , Nucleic Acid Hybridization , Plasmids , T-Phages/enzymology
16.
Biochim Biophys Acta ; 425(2): 175-84, 1976 Mar 04.
Article in English | MEDLINE | ID: mdl-1252498

ABSTRACT

Salt-washed ribosomes from rabbit reticulocytes stimulate seven partially purified aminoacyl-tRNA synthetases up to threefold: arginyl-, alanyl-, isoleucyl-, lysyl-, methionyl-, phenylalanyl- and valyl-tRNA synthetase. Both isolated subunits but not total ribosomal RNA show the stimulation. The increase in synthetase activity is also found in a highly purified Escherichia coli system employing homogenous (E. coli)phenyl-alanyl-tRNA synthetase and (E. coli)- tRNAPhe. The biological significance of the stimulation is discussed.


Subject(s)
Amino Acyl-tRNA Synthetases/metabolism , Reticulocytes/metabolism , Ribosomes/metabolism , Animals , Binding Sites , Cell Fractionation , Magnesium/pharmacology , Protein Binding , Protein Biosynthesis , RNA, Transfer/metabolism , Rabbits , Reticulocytes/drug effects , Ribosomes/drug effects , Valine
17.
J Clin Endocrinol Metab ; 90(5): 2775-80, 2005 May.
Article in English | MEDLINE | ID: mdl-15713700

ABSTRACT

The use of 131I in the treatment of multinodular goiters (MNG) is well established. We evaluated the effect of 30 microCi 131I (1.11 GBq) in 18 patients with MNG with the aid of two injections of 0.1 mg recombinant human TSH (rhTSH), given on d 1 and 2. A dose of 30 microCi 131I was given on d 3. TSH, T3, free T4, and thyroglobulin were measured on d 1, 2, 3, 5, 10, 30, 60, 90, and 180, and antithyroid antibodies were measured on d 1, 30, 90, and 180. Twenty-four-hour 131I uptake measured 1-3 months before rhTSH increased from 12.3 +/- 6.2 to 53.5 +/- 10.9% (P < 0.0001), free T4 from 1.3 +/- 0.2 to peak 3.2 +/- 1.1 ng/dl levels (P < 0.0001), T3 from 113.9 +/- 35.0 to peak 332.2 +/- 123.0 ng/dl levels (P < 0.0001), TSH from 0.76 +/- 0.71 to peak 18.9 +/- 5. 3 mU/liter levels (P < 0.0001), and thyroglobulin from 280.9 +/- 370.0 to peak 1838.5 +/- 1360.7 ng/dl levels (P = 0.001). Painful thyroiditis (33%) and mild thyrotoxicosis (39%) constituted minor side effects. There were no changes in echocardiographic parameters, done before and after rhTSH administration, on d 3. Hypothyroidism developed in 65%. Mean goiter size, measured by computed tomography, decreased from 97.9 +/- 45.4 to 65.5 +/- 47.3 ml (P < 0.0001; reduction: 39 +/- 19%) after 6 months. We conclude that rhTSH is a safe and efficient therapeutic tool in the treatment of MNG allowing the use of outpatient therapeutic 131I doses.


Subject(s)
Goiter, Nodular/radiotherapy , Iodine Radioisotopes/therapeutic use , Thyrotropin/therapeutic use , Aged , Echocardiography, Doppler , Female , Goiter, Nodular/blood , Goiter, Nodular/diagnostic imaging , Humans , Male , Middle Aged , Recombinant Proteins/therapeutic use , Thyroglobulin/blood , Thyrotropin/blood , Thyroxine/blood
18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(4 Pt 2): 046201, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15903764

ABSTRACT

We present detailed investigations of the experimental signatures of chaos-assisted tunneling in the two-dimensional annular billiard, as already summarized in Phys. Rev. Lett. 84, 867 (2000). We have performed analog experiments with two-dimensional, electromagnetic resonators allowing for a direct simulation of the corresponding quantum system. Spectra from a superconducting cavity with a high-frequency resolution are combined with electromagnetic intensity distributions of high spatial resolution experimentally determined using a normal conducting twin cavity. Thereby all eigenmodes were obtained with properly identified quantum numbers. Besides distributions of quasi-doublet splittings, which serve as fundamental observables for the tunneling between whispering gallery types of modes, we also focus on the distributions of resonance widths of the doublets. These directly reflect the role of lifetime of certain modes in the tunneling process. Here, as theoretically expected, the class of so-called beach modes is found to play a particular role in mediating between regular and chaotic states to enhance the tunneling strength. This behavior is found in the spectrum and also in the structure of the wave functions.

19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(4 Pt 2): 046202, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15903765

ABSTRACT

A new measure for statistical properties of the wave function components of quantum systems, the distribution of the product of two partial widths, is introduced. It is tested with data obtained in analog experiments with microwave billiards, where the product of two partial widths equals the resonance strengths in the microwave spectra. The billiards are from the family of the Limaçons, one with chaotic and two with mixed classical dynamics. For completely chaotic systems the partial widths generically obey a Porter-Thomas distribution. We show that in this case the distribution of their product equals a K0 distribution. While we find deviations of the experimental strength distribution from the K0 distribution for the billiards with mixed dynamics, the distributions agree perfectly for the chaotic billiard, when taking into account the experimental threshold of detection in the theoretical description. Hence, the strength distribution provides another stringent test for the connection between statistical properties of systems with classical chaotic dynamics and random matrix theory.

20.
Rofo ; 177(12): 1625-30, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16333784

ABSTRACT

PURPOSE: The feasibility of high-resolution arterial spin labeling (ASL) perfusion imaging of the kidneys was tested and proven at 3 Tesla using a flow-sensitive alternating inversion recovery (FAIR) true fast imaging in steady precession (TrueFISP) technique. MATERIALS AND METHODS: Kidney perfusion maps of six healthy volunteers and two patients were acquired using a clinical 3-Tesla whole-body scanner. An ASL sequence with FAIR spin preparation and a TrueFISP signal detection strategy was adapted for high-resolution perfusion imaging of the kidneys at 3 Tesla. To avoid banding artifacts in TrueFISP images, which are generally prominent at 3 Tesla, a frequency scout was implemented. Perfusion maps with an in-plane resolution of 1.5 mm were recorded in transverse and coronal orientation. For fast mapping of whole-kidney perfusion, an in-plane resolution of 2 mm was applied. RESULTS: In all volunteers and patients, high-resolution perfusion images with excellent image quality were able to be obtained in a measuring time of approximately 10 minutes. The whole kidney was able to be mapped with good image quality in less than 10 minutes. For all slices, a suitable frequency offset made it possible to reproduce the kidneys without TrueFISP artifacts. Perfusion values of the renal cortex ranged from 250 ml/100 g/min up to 400 ml/100 g/min (mean cortical perfusion right kidney 316 +/- 43, left 336 +/- 40). CONCLUSION: High-resolution ASL perfusion images of the whole kidney were able to be obtained with good image quality by means of a 3 Tesla MR setting within a clinically applicable measuring time, thus providing an alternative to conventional perfusion imaging involving potentially nephrotoxic contrast media.


Subject(s)
Kidney/blood supply , Magnetic Resonance Imaging/methods , Renal Circulation , Adult , Age Factors , Aged , Artifacts , Feasibility Studies , Humans , Image Processing, Computer-Assisted , Kidney Cortex/blood supply , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/physiopathology , Magnetic Resonance Imaging/instrumentation , Models, Theoretical
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