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1.
Nature ; 590(7847): 566-570, 2021 02.
Article in English | MEDLINE | ID: mdl-33627809

ABSTRACT

When a heavy atomic nucleus splits (fission), the resulting fragments are observed to emerge spinning1; this phenomenon has been a mystery in nuclear physics for over 40 years2,3. The internal generation of typically six or seven units of angular momentum in each fragment is particularly puzzling for systems that start with zero, or almost zero, spin. There are currently no experimental observations that enable decisive discrimination between the many competing theories for the mechanism that generates the angular momentum4-12. Nevertheless, the consensus is that excitation of collective vibrational modes generates the intrinsic spin before the nucleus splits (pre-scission). Here we show that there is no significant correlation between the spins of the fragment partners, which leads us to conclude that angular momentum in fission is actually generated after the nucleus splits (post-scission). We present comprehensive data showing that the average spin is strongly mass-dependent, varying in saw-tooth distributions. We observe no notable dependence of fragment spin on the mass or charge of the partner nucleus, confirming the uncorrelated post-scission nature of the spin mechanism. To explain these observations, we propose that the collective motion of nucleons in the ruptured neck of the fissioning system generates two independent torques, analogous to the snapping of an elastic band. A parameterization based on occupation of angular momentum states according to statistical theory describes the full range of experimental data well. This insight into the role of spin in nuclear fission is not only important for the fundamental understanding and theoretical description of fission, but also has consequences for the γ-ray heating problem in nuclear reactors13,14, for the study of the structure of neutron-rich isotopes15,16, and for the synthesis and stability of super-heavy elements17,18.

2.
Hamostaseologie ; 25(3): 272-8; quiz 279-80, 2005 Aug.
Article in German | MEDLINE | ID: mdl-16113751

ABSTRACT

Anticoagulation during renal replacement therapy is recommended to avoid thrombosis of the filter devices and to maintain the blood flow. However, in the case of multiorgan failure and sepsis, an imminent bleeding complication in patients with acute renal failure may cause the need for an extracorporeal circulation without anticoagulation. The most common drug used in renal replacement therapy is the unfractionated heparin (UFH). With low molecular weight heparin (LMWH) good experiences are reported, too. Based on the level of evidence from clinical studies plasma measurement of heparin is indispensable for patients with renal insufficiency. The activated whole blood clotting time (ACT), the activated partial thromboplastin time (aPTT), and the determination of the anti-factor Xa activity (anti Xa) with chromogenic substrates are available as routine as well as as point-of-care tests. To monitor plasma levels of LMWH the anti Xa assay serves exclusively as a suitable monitoring. The anti Xa assay using chromogenic substrates is the most specific and valid one for monitoring heparin therapy. In lack of large controlled studies for the anticoagulation therapy and its monitoring with the anti Xa test in acute renal failure, the current experiences are based on the results of chronic renal replacement therapy.


Subject(s)
Heparin/therapeutic use , Renal Dialysis/methods , Anticoagulants/therapeutic use , Drug Monitoring , Humans , Kidney Failure, Chronic/therapy
3.
Arch Virol ; 148(10): 1957-68, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14551818

ABSTRACT

We have analysed the sequence variability in the putative reverse transcriptase (RT)/ribonuclease H (RNaseH) and the C-terminal coat protein (CP)-coding regions from Taro bacilliform virus (TaBV) isolates collected throughout the Pacific Islands. When the RT/RNaseH-coding region of 22 TaBV isolates from Fiji, French Polynesia, New Caledonia, Papua New Guinea (PNG), Samoa, Solomon Islands and Vanuatu was examined, maximum variability at the nucleotide and amino acid level was 22.9% and 13.6%, respectively. Within the CP-coding region of 13 TaBV isolates from Fiji, New Caledonia, PNG, Samoa and the Solomon Islands, maximum variability at the nucleotide and amino acid level was 30.7% and 19.5%, respectively. Phylogenetic analysis showed that TaBV isolates from the Solomon Islands showed greatest variability while those from New Caledonia and PNG showed least variability. Based on the sequences of the TaBV RT/RNaseH-coding region, we have developed a PCR-based diagnostic test that specifically detects all known TaBV isolates. Preliminary indexing has revealed that TaBV is widespread throughout Pacific Island countries. A sequence showing approximately 50% nucleotide identity to TaBV in the RT/RNaseH-coding region was also detected in all taro samples tested. The possibility that this may represent either an integrated sequence or the genome of an additional badnavirus infecting taro is discussed.


Subject(s)
Badnavirus/isolation & purification , Colocasia/virology , Genetic Variation , Plant Diseases/virology , Polymerase Chain Reaction/methods , Badnavirus/genetics , Capsid Proteins/genetics , Molecular Sequence Data , Pacific Islands , Phylogeny , Plant Leaves/virology , RNA-Directed DNA Polymerase/genetics , Ribonuclease H/genetics , Sequence Analysis, DNA
4.
Plant Cell Rep ; 21(12): 1199-206, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12910370

ABSTRACT

Taro bacilliform virus (TaBV) is a pararetrovirus of the genus Badnavirus which infects the monocotyledonous plant, taro ( Colocasia esculenta). A region of the TaBV genome spanning nucleotides 6,281 to 12 (T1200), including the 3' end of open reading frame 3 (ORF 3) and the intergenic region to the end of the tRNA(met)-binding site, was tested for promoter activity along with four different 5' deletion fragments (T600, T500, T250 and T100). In transient assays, only the T1200, T600, T500 fragments were shown to have promoter activity in taro leaf, banana suspension cells and tobacco callus. When these three promoters were evaluated in stably transformed, in vitro-grown transgenic banana and tobacco plants, all were found to drive near-constitutive expression of either the green fluorescent protein or beta-glucuronidase (GUS) reporter gene in the stem (or pseudostem), leaves and roots, with strongest expression observed in the vascular tissue. In transgenic banana leaves, the T600 promoter directed four-fold greater GUS activity than that of the T1200, T500 and the maize polyubiquitin-1 promoters. In transgenic tobacco leaves, the levels of GUS expression directed by the three promoters was between four- and ten-fold lower than that of the double Cauliflower mosaic virus 35S promoter. These results indicate that the TaBV-derived promoters may be useful for the high-level constitutive expression of transgenes in either monocotyledonous or dicotyledonous species.


Subject(s)
Badnavirus/genetics , Promoter Regions, Genetic , Cloning, Molecular , Colocasia/virology , Culture Techniques , Gene Expression Regulation , Musa/genetics , Nicotiana/genetics , Transgenes
5.
Arch Virol ; 148(5): 937-49, 2003 May.
Article in English | MEDLINE | ID: mdl-12721801

ABSTRACT

Taro bacilliform virus (TaBV) has been classified as a putative badnavirus based on its non-enveloped, bacilliform virion morphology and transmission by mealybugs. The complete nucleotide sequence of a Papua New Guinea isolate of TaBV has now been determined and comprises 7458 bp. The genome contains four open reading frames (ORFs) on the plus-strand that potentially encode proteins of 17, 16, 214 and 13 kDa. The size and organisation of TaBV ORFs 1-3 is similar to that of most other badnaviruses, while the location of ORF 4 is similar to that of ORF 4 and ORF X of the atypical badnaviruses Citrus yellow mosaic virus and Cacao swollen shoot virus, respectively. The putative amino acid sequence of TaBV ORF 3 contained motifs that are conserved amongst badnavirus proteins including aspartic protease, reverse transcriptase (RT) and ribonuclease H (RNase H). The highly conserved putative plant tRNA(met)-binding site was also present in the 935 bp intergenic region of TaBV. Phylogenetic analysis using the amino acid sequence of ORF 3 showed that TaBV branched most closely to Dioscorea bacilliform virus. These results confirm that TaBV is a pararetrovirus of the genus Badnavirus, family Caulimoviridae.


Subject(s)
Badnavirus/genetics , Colocasia/virology , Genome, Viral , Amino Acid Sequence , Animals , Badnavirus/chemistry , Base Sequence , Conserved Sequence , Molecular Sequence Data , Open Reading Frames , Phylogeny , Plant Diseases/virology
6.
Cell Tissue Res ; 311(1): 99-105, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12483289

ABSTRACT

This study examines the expression of the photopigment gene in the developing retina of the freshwater crayfish Procambarus clarkii(Crustacea, Malacostraca, Decapoda). Both sense and anti-sense RNA probes were used for in situ hybridization (ISH) of whole embryos collected at various stages during development. A characteristic of retinal development is the formation of screening pigment in the retinular cells of the retinal ommatidia. This pigmentation is seen as a band that begins at the lateral side of the retinal field and progresses medially. At hatching the retina is approximately 50% pigmented. ISH of whole embryos shows that expression of the photopigment gene by the retinular cells correlates with the extent of the screening pigment band in the retina and with the presence of rhabdoms within the ommatidia. Sections taken through embryos after being hybridized indicate that staining is localized in the cytoplasm of the retinular cells and in the axonal region below the basement membrane. No staining reaction was seen in the rhabdoms of older ommatidia. ISH staining was also seen at the anterior midline of the protocerebrum where extraretinal photoreceptors have been reported. The data presented here show a close correlation of opsin expression within the retinular cells of the ommatidia and the formation of the very early rhabdoms, similar to Drosophila. The results will be discussed in relation to recent studies in Drosophila that suggest rhodopsin plays a role in effecting the organization of the terminal web-like cytoskeleton at the base of the developing rhabdom microvilli.


Subject(s)
Gene Expression Regulation, Developmental , Photoreceptor Cells, Invertebrate/embryology , Photoreceptor Cells, Invertebrate/physiology , Retinal Pigments/genetics , Animals , Astacoidea , Cell Differentiation , In Situ Hybridization , Photoreceptor Cells, Invertebrate/cytology
7.
Unfallchirurg ; 106(12): 1020-8, 2003 Dec.
Article in German | MEDLINE | ID: mdl-14727038

ABSTRACT

Deep vein thrombosis (DVT) is reported in up to 40% of trauma patients. The individual risk is nearly unpredictable. A daily single dose of a low molecular weight heparin (LMWH) was administered as prophylaxis to 518 trauma patients who were examined preoperatively and up to 10 days postoperatively in a prospective study. They were divided into two groups: group I comprised surgery of the hip and femur as well as total knee replacement and group II knee and lower leg surgery. Thrombin-antithrombin complex and D-dimer were analyzed. A second daily dose of LMWH was added if D-dimer exceeded the cutoff. If ultrasound was suspicious for DVT venography was added. Deep vein thrombosis was seen in five cases (group I=4, group II=1), without pulmonary embolism. TAT and D-dimer were significantly higher in group I than in group II ( p<0.005). One hundred patients, 79 of them belonging to group I, were treated with a second dose of LMWH. The daily cutoff had the highest sensitivity and specificity for day 4. Due to individual monitoring of coagulation markers, the risk for thromboembolism compared to actual data in the literature seems to be reduced.


Subject(s)
Anticoagulants/administration & dosage , Fibrin Fibrinogen Degradation Products/metabolism , Fibrinolytic Agents/administration & dosage , Heparin, Low-Molecular-Weight/administration & dosage , Peptide Hydrolases/blood , Postoperative Complications/prevention & control , Thromboembolism/prevention & control , Wounds and Injuries/surgery , Antithrombin III , Humans , Monitoring, Physiologic , Prospective Studies , Risk Factors , Time Factors , Trauma Severity Indices
8.
Z Kardiol ; 91(3): 203-11, 2002 Mar.
Article in German | MEDLINE | ID: mdl-12001536

ABSTRACT

BACKGROUND: Recently, coronary artery bypass grafting (CABG) on the beating heart with avoidance of extracorporeal circulation (off-pump CABG technique) has been gaining increasing importance in modern cardiac surgery. The object of this prospective study was to compare postoperative kinetic and patterns of cardiac troponin I (cTnI), T (cTnT), and creatine kinase MB (CKMB) activities after off-pump CABG versus conventional on-pump CABG. METHODS: We studied 106 patients who underwent first-time elective on-pump (group I, n = 69, 56 male, 13 female, mean age: 64.3 +/- 9.9 years, mean ejection fraction: 56 +/- 15%) or off-pump (group II, n = 37, 24 male, 13 female, mean age: 68.4 +/- 9.1 years, mean ejection fraction: 57 +/- 13%) CABG surgery via median sternotomy. CTn I and cTnT levels, total creatine kinase (CK) and CK-MB activities in the serum were measured before operation, up on arrival at the ICU and 6, 12, 24, 48 and 120 hours later. Serial 12-lead ECGs were recorded preoperatively and on days 1, 2 and 5. RESULTS: Serum concentrations of cardiac troponins in all patients were preoperatively either not detectable or in the normal range and significantly increased after surgery. In group I, one patient developed a Q wave myocardial infarction, one patient a non-Q wave infarction and two patients a new left bundle branch block on the ECG. One patient of group II developed a new Q-wave myocardial infarction and another patient permanent atrial fibrillation associated with a continuous arrhythmia. All patients with a myocardial infarction in the ECG showed significant elevation of concentrations or activities of these biochemical markers. The median postoperative peak values for cTnI were measured at 24 h in both groups (2.7 micrograms/l, 95%-CI: [2.2, 3.2] in group I and 1.1 micrograms/l, 95%-CI: [0.5, 1.3] in group II). CTnT postoperatively presented an earlier median peak of 0.128 microgram/l at 12 h in group II (95%-CI: [0.041, 0.146]) than in group I at 48 h (0.298 microgram/l, 95%-CI: [0.254, 0.335]). CONCLUSIONS: All patients undergoing CABG surgery with or without extracorporeal circulation postoperatively showed an increase of cardiac troponin levels. After uncomplicated coronary revascularization, patients with the off-pump CABG technique continuously presented lower serum cardiac troponin concentrations than those with the on-pump CABG technique. CTnI showed the same patterns of release in both groups with different median postoperative peak values at 24 h. The patterns off cTnT release following CABC surgery with or without extracorporal circulation were different: CTnT reaches its postoperative peak value in patients with the off-pump CABG technique earlier than those with the on-pump CABG technique (12 h postoperatively versus 48 h).


Subject(s)
Biomarkers/blood , Cardiopulmonary Bypass , Creatine Kinase/blood , Isoenzymes/blood , Myocardial Infarction/surgery , Myocardial Ischemia/enzymology , Troponin I/blood , Troponin T/blood , Aged , Creatine Kinase, MB Form , Electrocardiography , Female , Humans , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/enzymology , Myocardial Ischemia/diagnosis , Postoperative Complications/diagnosis , Postoperative Complications/enzymology , Stroke Volume/physiology
9.
Biotechniques ; 31(5): 1122-4, 1126, 1128-9, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11730018

ABSTRACT

Linear dsDNA composed of tandem repeats may be exponentially amplified by the strongly strand-displacing Bst DNA polymerase (large fragment) and two primers specific for opposite strands. When the repetitive DNA is derivedfrom rolling circle replication of a circular template, the reaction is termed cascade rolling circle amplification (CRCA). We have developed a variant of CRCA in which one primer is attached to the surface of a microwell and the other is labeled, thus enabling detection of amplified material using an ELISA-like protocol. The circular template is derived by annealing and ligation of a padlock on target DNA. It was found that there was good correlation between the synthesis of amplified material and signal. The specificity of the reaction with respect to single-nucleotide polymorphisms was investigated, and it was found that Bst DNA polymerase is prone to extension from primers with mismatched 3' ends. Reliable single nucleotide specificity was only obtained when pre-synthesized amplified material was interrogated by competitive primer extension.


Subject(s)
DNA Primers/genetics , DNA-Directed DNA Polymerase/genetics , Nucleic Acid Amplification Techniques , Polymorphism, Single Nucleotide , Sensitivity and Specificity
10.
Circulation ; 104(25): 3125-31, 2001 Dec 18.
Article in English | MEDLINE | ID: mdl-11748112

ABSTRACT

BACKGROUND: Complement activation during reperfusion of ischemic myocardium augments myocardial injury, and complement inhibition with C1-esterase inhibitor (C1-INH) at the time of reperfusion exerts marked cardioprotective effects in experimental studies. Application of C1-INH in newborns, however, was recently reported to have dangerous and even lethal side effects. This study addresses the essential role of dosage in studies using C1-INH. METHODS AND RESULTS: Cardioprotection by C1-INH was examined in a pig model with 60 minutes of coronary occlusion followed by 120 minutes of reperfusion. C1-INH was administered intravenously 5 to 10 minutes before coronary reperfusion without heparin at a dose of 40, 100, and 200 IU/kg body wt. Compared with the NaCl controls, C1-INH 40 IU/kg reduced myocardial injury (44.1+/-13.8% versus 76.7+/-4.6% necrosis of area at risk, P/=100 IU/kg) of C1-INH will provoke detrimental side effects, probably via its procoagulatory action.


Subject(s)
Complement C1 Inactivator Proteins/pharmacology , Myocardial Ischemia/complications , Reperfusion Injury/prevention & control , Anaphylatoxins/metabolism , Animals , Blood Gas Analysis , Cardiac Output/drug effects , Complement C1 Inactivator Proteins/metabolism , Coronary Circulation/drug effects , Creatine Kinase/blood , Creatine Kinase/drug effects , Dose-Response Relationship, Drug , Heart Ventricles/drug effects , Heart Ventricles/pathology , Heart Ventricles/physiopathology , Hemodynamics/drug effects , Lactic Acid/blood , Microscopy, Electron , Myocardial Ischemia/blood , Myocardial Ischemia/physiopathology , Myocardium/metabolism , Myocardium/pathology , Myocardium/ultrastructure , Necrosis , Oxygen/blood , Partial Pressure , Reperfusion Injury/etiology , Swine , Troponin T/blood , Troponin T/drug effects
11.
Clin Appl Thromb Hemost ; 7(4): 330-4, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11697719

ABSTRACT

For the resection of an esophagus carcinoma a mortality rate of 2 to 30% was described. It is still unclear whether an abdominothoracic or transhiatal intervention is superior regarding the outcome. To investigate the prognostic value of fibrinolytic markers, plasmin-alpha2-antiplasmin (PAP) and D-dimer (DD) values were determined daily in the early postoperative period for 11 days. In addition, the course of PAP and DD concentrations was compared with the method of esophagectomy. Of the 28 patients enclosed in the study, 5 died between day 10 and day 34 owing to adult respiratory distress syndrome and septicemia. The PAP and DD concentrations increased in survivors after surgery until day 5 and day 7, respectively. The concentrations were twofold and 10-fold higher than the upper reference level. In contrast, four of five nonsurvivors showed an inadequate increase in PAP concentrations within the reference range, whereas the course of DD was inconspicuous. The sensitivity and specificity of PAP and DD in respect to a fatal outcome was calculated by receiver operating characteristic analysis based on all results: sensitivity 76% (PAP-cut off value 760 microg/L) and 49% (DD 6 mg/L), specificity 77% and 72%, respectively. The biochemical markers showed no significant differences between the abdominothoracic and transhiatal esophagectomy. In the abdominothoracic intervention, lower PAP and higher DD concentrations were observed. The results showed that the PAP concentrations could detect a fatal outcome within the first 5 days after surgery.


Subject(s)
Esophagectomy/mortality , Fibrinolysis , Adult , Aged , Antifibrinolytic Agents/blood , Biomarkers/blood , Esophageal Neoplasms/complications , Esophageal Neoplasms/mortality , Esophageal Neoplasms/surgery , Esophagectomy/adverse effects , Female , Fibrin Fibrinogen Degradation Products/analysis , Fibrinolysin , Humans , Male , Middle Aged , Postoperative Period , Prognosis , ROC Curve , Sensitivity and Specificity , Survival Rate , Time Factors , alpha-2-Antiplasmin
12.
Arterioscler Thromb Vasc Biol ; 21(10): 1668-73, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11597943

ABSTRACT

P-selectin is a cellular adhesion molecule that mediates the interaction of activated endothelial cells or platelets with leukocytes. Increased levels of soluble P-selectin have been reported in various cardiovascular disorders. We measured serum soluble P-selectin levels as well as 3 polymorphisms of the P-selectin gene (C-2123G, A-1969G, and Thr715Pro) in a large cohort of patients with documented coronary artery disease (n=869) and a healthy control group (n=334). The 3 P-selectin polymorphisms were strongly associated with P-selectin levels and altogether explained 7.3% and 18.6% of the P-selectin variability in patients and controls, respectively. Genotype distributions did not significantly differ between patients and controls. P-selectin levels were increased in patients younger than 55 years of age compared with controls (135.2 vs 114.3 ng/mL, P<0.01). On the contrary, patients older than 65 years of age had significantly lower P-selectin levels than did controls (121.5 vs 134.7 ng/mL, P<0.02). In intermediate age groups, P-selectin levels did not significantly differ between the 2 groups. In conclusion, this study revealed a strong association between P-selectin gene polymorphisms and serum P-selectin levels and a complex age-dependent relation between soluble P-selectin levels and coronary artery disease, which suggests that this molecule might have different roles in the atherothrombotic process.


Subject(s)
Coronary Artery Disease/etiology , Coronary Artery Disease/genetics , P-Selectin/blood , P-Selectin/genetics , Polymorphism, Single Nucleotide , Cohort Studies , Coronary Artery Disease/blood , Female , Humans , Male , Middle Aged , Risk Factors , Smoking/adverse effects
13.
Circulation ; 104(12): 1336-42, 2001 Sep 18.
Article in English | MEDLINE | ID: mdl-11560847

ABSTRACT

BACKGROUND: Vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1, and E-selectin mediate adhesion and transmigration of leukocytes to the vascular endothelial wall and may promote plaque growth and instability. In a prospective study, we evaluated the effect of soluble adhesion molecules on the risk of future cardiovascular events among patients with angiographically documented coronary artery disease (CAD). Methods and Results- -We obtained baseline samples from a prospective cohort of 1246 patients with CAD. Besides various markers of inflammation, soluble VCAM-1 (sVCAM-1), sICAM-1, and sE-selectin were determined. Follow-up information on cardiovascular events was obtained (mean, 2.7; maximum, 4.1 years). Independently higher levels of sVCAM-1 (1932 versus 1128 ng/mL; P<0.0001), sICAM-1 (353 versus 287 ng/mL; P=0.015), and sE-selectin (81 versus 63 ng/mL; P=0.003) were observed in patients with future death from cardiovascular causes. In a multivariate model, fatal risk was 2.1-fold (1.1 to 4.0) higher in patients within the top quartile of baseline sVCAM-1 concentrations compared with lower quartiles. This association was present independent of general inflammatory response as reflected by low or high C-reactive protein (hs-CRP) levels. In a model that simultaneously controlled for all inflammatory and soluble adhesion markers determined, only sVCAM-1 remained independently significant for future fatal cardiovascular events, with a 2.8-fold increase in risk (P=0.003). CONCLUSIONS: Soluble adhesion molecules sVCAM-1, sICAM-1, and sE-selectin were significantly related to future death from cardiovascular causes among patients with documented CAD. Especially sVCAM-1 added to the predictive value of classic risk factors and hs-CRP in determining the risk of future cardiovascular death.


Subject(s)
Cell Adhesion Molecules/blood , Coronary Disease/blood , Coronary Disease/mortality , Aged , C-Reactive Protein/analysis , Cohort Studies , E-Selectin/blood , Female , Follow-Up Studies , Germany/epidemiology , Humans , Intercellular Adhesion Molecule-1/blood , Male , Middle Aged , Predictive Value of Tests , Proportional Hazards Models , Prospective Studies , Risk Factors , Sensitivity and Specificity , Survival Rate , Vascular Cell Adhesion Molecule-1/blood
14.
Cell Tissue Res ; 305(1): 147-58, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11512667

ABSTRACT

Pattern formation and ommatidial differentiation were examined in the developing retina of the lobster Homarus americanus using light and electron microscopy. In the lobster the retina differentiates from the surface ectoderm that covers the optic primordia. Initially a single band of proliferation moves across this surface ectoderm. Immediately following this wave of proliferation, rows of ommatidial cell clusters appear. The earliest cell clusters are often seen adjacent to dividing cells of the proliferation band. The changing organization of the first seven rows of ommatidial clusters, visible at the surface of the retina, reveals events in early ommatidial differentiation. A rosette-like cluster of 18 cells forms the first row. Each stage following the rosette clusters occurs in a separate staggered row. Developing ommatidia have a central cluster of retinula cells, whose organization changes at each stage. Four cone cells enclose the retinula cells in each cluster and extend to the surface. In the seventh row, rhabdome formation begins and the retinula cells recede, leaving only cone cells visible at the retinal surface. This change initiates the two-tiered organization of the adult ommatidium. In 70% embryos, asymmetries in the position of the R8 axon around R7 create an equatorial line separating the dorsal and ventral halves of the retina. Possible mechanisms for the formation of these asymmetries are discussed. Postembryonic growth of the retina continues in stage VI juvenile animals along the ventral edge of the retina.


Subject(s)
Nephropidae/growth & development , Photoreceptor Cells, Invertebrate/cytology , Photoreceptor Cells, Invertebrate/growth & development , Age Factors , Animals , Astacoidea , Cell Division , Drosophila melanogaster
15.
Circulation ; 104(1): 25-31, 2001 Jul 03.
Article in English | MEDLINE | ID: mdl-11435333

ABSTRACT

BACKGROUND: The number of infectious pathogens to which an individual has been exposed (infectious burden) may correlate with coronary artery disease (CAD). In a prospective study, we evaluated the effect of 8 pathogens and the aggregate pathogen burden on the risk for future fatal cardiac events among patients with angiographically documented CAD. Methods and Results-In 1018 patients, IgG or IgA antibodies to herpes simplex virus types 1 and 2, cytomegalovirus, Epstein-Barr virus, Haemophilus influenzae, Chlamydia pneumoniae, Mycoplasma pneumoniae, and Helicobacter pylori were determined. Moreover, highly sensitive C-reactive protein was measured. Follow-up information on cardiovascular events was obtained (mean 3.1 years, maximum 4.3 years). Seropositivities to Epstein-Barr virus (P=0.001), H pylori (P=0.002), and herpes simplex virus type 2 (P=0.045) were independently associated with the future risk of cardiovascular death. An increasing number for pathogen burden was significantly predictive of the long-term prognosis (P<0.0001). Infectious burden divided into 0 to 3, 4 or 5, and 6 to 8 seropositivities was associated with an increasing mortality of 3.7%, 7.2%, and 12.6%, respectively. Patients seropositive to >5 pathogens compared with those seropositive to <4 pathogens had a 5.1 (1.4 to 18.3) higher risk of future cardiac death. This result was mainly driven by the pathogen burden of seropositivities to Herpesviridae (P<0.0001). The prognostic impact of total or viral pathogen burden was independent of the C-reactive protein level. CONCLUSIONS: These results support the hypothesis that the number of infectious pathogens to which an individual has been exposed independently contributes to the long-term prognosis in patients with documented CAD.


Subject(s)
Bacterial Infections/diagnosis , Coronary Disease/microbiology , Virus Diseases/diagnosis , Antibodies, Bacterial/blood , Antibodies, Viral/blood , Bacterial Infections/epidemiology , Bacterial Infections/immunology , C-Reactive Protein/metabolism , Chlamydophila pneumoniae/immunology , Comorbidity , Coronary Disease/diagnosis , Coronary Disease/epidemiology , Coronary Disease/immunology , Cytomegalovirus/immunology , Female , Follow-Up Studies , Haemophilus influenzae/immunology , Helicobacter pylori/immunology , Herpesvirus 1, Human/immunology , Herpesvirus 2, Human/immunology , Herpesvirus 4, Human/immunology , Humans , Immunoglobulin G/blood , Male , Middle Aged , Mycoplasma pneumoniae/immunology , Odds Ratio , Prognosis , Risk Assessment , Seroepidemiologic Studies , Virus Diseases/epidemiology , Virus Diseases/immunology
16.
Thorac Cardiovasc Surg ; 49(3): 137-43, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11440002

ABSTRACT

BACKGROUND: Cardiac troponin I (cTnI) has been shown to be a specific marker for myocardial injury in cardiac surgery. The object of this prospective study was to determine the patterns and kinetic and diagnostic value of cTnI, cardiac troponin T (cTnT), and creatine kinase MB (CKMB) activity after minimally invasive coronary revascularization using an octopus device on the beating heart (OPCAB). METHODS: 48 patients (33 male/15 female, mean age 68.3 +/- 8.7 years) underwent their first elective OPCAB surgery with median sternotomy without mortality. The mean number of grafts was 2.0 +/- 0.8 per patient. Preoperative mean ejection fraction was 56.6 % +/- 14.9%. CTnI and T levels, total creatine kinase (CK) and CK-MB activity in the serum were measured before operation, at arrival at the ICU, and 6, 12, 24, 48 and 120 hours afterward. Serial 12-lead ECGs were recorded preoperatively and at days 1, 2 and 5. The relationship between perioperative data and postoperative cTnI and cTnT levels and CKMB were statistically identified for all variables. RESULTS: The best cutoff value for cTnI was 8.35 micrograms/l. The patients were grouped by the ECG findings and maximal slopes of cTnI postoperatively (group I: unchanged ECG and cTnI < 8.35 micrograms/l, n = 38; group II: unchanged ECG and cTnI > 8.35 micrograms/l n = 6; group III: Q-wave in ECG and cTnI > 8.35 micrograms/l, n = 4). Baseline serum concentrations of cTnI were in the normal range, and significantly increased after surgery with a peak 24h after the operation. Maximal slopes of cTnI ranged in group II between 9.1 and 18.0 micrograms/l, and in group III between 35.9 and 88.8 micrograms/l. There was strong concordance between maximum cTnI, cTnT (p < 0.0001) and CK-MB levels (p = 0.003). First cTnI levels immediately post-op correlated with the maximum cTnI levels during the postoperative course (p = 0.009). CONCLUSIONS: CTnI after minimal invasive surgery shows a characteristic pattern with a maximum at 24h after the operation. The measurement of postoperative biochemical marker concentrations, specially cTnI, reflects myocardial injury incurred during the procedure. It is an accurate method for confirming or excluding a perioperative myocardial injury diagnosis after OPCAB surgery.


Subject(s)
Creatine Kinase/metabolism , Isoenzymes/metabolism , Myocardial Revascularization/instrumentation , Troponin I/blood , Troponin T/blood , Aged , Biomarkers , Creatine Kinase, MB Form , Electrocardiography , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/surgery , Prospective Studies , ROC Curve , Radionuclide Imaging , Sensitivity and Specificity , Vascular Patency/physiology
17.
Circulation ; 103(24): 2915-21, 2001 Jun 19.
Article in English | MEDLINE | ID: mdl-11413080

ABSTRACT

BACKGROUND: Prospective data relating previous exposure to cytomegalovirus (CMV) to the risk of cardiac mortality are controversial. We investigated the effect of previous exposure to CMV infection on the risk of future cardiac disease-related death in relation to an underlying inflammatory response. METHODS AND RESULTS: coronary angiography was performed in 1134 subjects, and 989 patients with documented coronary artery disease were studied prospectively. CMV-IgG titers and interleukin (IL)-6 levels were measured before angiography. Increasing titers of CMV correlated with the elevation of IL-6 levels (P<0.001) after adjustment for possible confounders. All patients were followed up for a median of 3.1 years (maximum 4.3 years). During follow-up, 96 patients died, 70 of cardiac disease. Overall, CMV seropositivity was not related to cardiac mortality after adjustment for confounding variables (P=0.19). In contrast, in patients with elevated IL-6 levels (>/=11.9 pg/mL, median level), CMV seropositivity was independently associated with a 3.2-fold (95% CI 1.4 to 7.3, P=0.007) increase in risk of future cardiac death, whereas in individuals without IL-6 elevation, previous CMV infection had no effect on cardiac mortality. CONCLUSIONS: MV seropositivity in patients with an inflammatory response is independently associated with future cardiac mortality, whereas this association is lost in patients who do not demonstrate an inflammatory response. These data support the hypothesis that the atherosclerotic effects of CMV are mediated through an underlying inflammatory response.


Subject(s)
Coronary Disease/blood , Coronary Disease/mortality , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/diagnosis , Interleukin-6/blood , Aged , Antibodies, Viral/blood , C-Reactive Protein/metabolism , Cholesterol, HDL/blood , Coronary Angiography , Coronary Disease/complications , Coronary Disease/diagnosis , Cytomegalovirus Infections/complications , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Germany , Humans , Inflammation/blood , Inflammation/complications , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , Prognosis , Prospective Studies , Regression Analysis , Risk Assessment , Risk Factors , Survival Rate
18.
Scand J Clin Lab Invest ; 61(3): 227-35, 2001 May.
Article in English | MEDLINE | ID: mdl-11386609

ABSTRACT

An analytical and clinical evaluation of cardiac troponin I (cTnI) on the IMMULITE system is presented. The assay results were compared with those of the Stratus II and the Dimension RxL-HM. A between-run imprecision CV < 20% was found at a cTnI concentration of 0.23 microg/L (functional limit of detection). On the basis of a reference study including 215 patients without ischemic heart disease (97.5th percentile: 0.294 microg/L) and 36 patients clinically classified as having stable angina pectoris (<0.22 microg/L) a preliminary cutoff level of 0.3 microg/L was defined. Assay linearity, sample stability, influence of sample material and method comparison studies were performed. In patients with Duchenne's disease, chronic hemodialysis treatment, pulmonary embolism, coronary artery bypass surgery and minimally cardiac surgery the cTnI results of the IMMULITE agreed better with the Dimension RxL-HM than with the Stratus II data. Of 142 samples from patients with unstable angina 67 samples were classified as cTnI positive with the IMMULITE, 76 with the Dimension RxL-HM, and 62 with the Stratus II. In conclusion, the new assay is sensitive for the determination of cTnI and easy to perform within 45 min.


Subject(s)
Immunoassay/instrumentation , Immunoassay/standards , Myocardial Ischemia/diagnosis , Troponin I/analysis , Adult , Aged , Aged, 80 and over , Angina, Unstable/diagnosis , Evaluation Studies as Topic , Female , Humans , Immunoassay/methods , Luminescent Measurements , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
19.
Herz ; 26 Suppl 1: 9-18, 2001 Apr.
Article in German | MEDLINE | ID: mdl-11349630

ABSTRACT

UNLABELLED: INFLAMMATORY PROCESS: Within the vessel wall is considered to be crucial for initiation and progression of atherosclerosis. As response to endothelial injury a focal inflammatory response arises which can lead to plaque vulnerability and rupture and a consecutive acute coronary syndrome. Systemic markers of inflammation like C-reactive protein (CRP) or interleukin (IL) 6 are elevated in stable angina and acute coronary syndrome and are associated with future cardiovascular events even in initially healthy people. Alongside classical risk factors infectious agents like cytomegalovirus or Chlamydia pneumoniae are discussed to be involved in the local and systemic inflammatory response. Seroepidemiological studies revealed disparate results of the association between antibody titers against Chlamydia pneumoniae or cytomegalovirus and prevalence of coronary artery disease or future cardiovascular events. In animal models Chlamydia pneumoniae and cytomegalovirus increase accelerated neointimal response, however, molecular mechanisms are not entirely clear. CONCLUSION: Whereas local and systemic inflammatory processes play a crucial role in atherogenesis and prognosis the causal role of infection in atherogenesis remains controversial.


Subject(s)
Coronary Disease/etiology , Infections/complications , Inflammation/complications , Acute Disease , Angina Pectoris/diagnosis , Angina Pectoris/etiology , Angina Pectoris/pathology , Angina, Unstable/diagnosis , Angina, Unstable/etiology , Angina, Unstable/pathology , Animals , Anti-Bacterial Agents/therapeutic use , C-Reactive Protein/analysis , Chlamydophila Infections/complications , Chlamydophila pneumoniae , Clinical Trials as Topic , Coronary Disease/diagnosis , Coronary Disease/pathology , Cytokines/blood , Cytomegalovirus Infections/complications , Humans , Inflammation/diagnosis , Multivariate Analysis , Myocardial Infarction/diagnosis , Myocardial Infarction/etiology , Myocardial Infarction/pathology , Prognosis , Prospective Studies , Regression Analysis , Risk Factors , Syndrome , Terminology as Topic
20.
Biotechniques ; 30(4): 852-6, 858, 860 passim, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11314268

ABSTRACT

We have demonstrated the isothermal in vitro amplification and multimerization of several different linear DNA targets using only two primers and the strongly strand-displacing exonuclease-negative Bst DNA polymerase. This reaction has been termed linear target isothermal multimerization and amplification (LIMA). LIMA has been compared with cascade rolling-circle amplification and has been found to be less sensitive but to yield similar variable-length multimeric dsDNA molecules. Products from several different LIMA reactions were characterized by restriction analysis and partial sequence determination. They were found to be multimers of subsets of the target sequence and were not purely primer derived. The sensitivities with respect to target concentration of several different LIMA reactions were determined, and they varied from 0.01 amol to 1 fmol. The sensitivity and specificity of LIMA were further tested using E. coli genomic DNA, and the selective amplification of a transposon fragment was demonstrated. A successful strategy for reducing LIMA-dependent background DNA synthesis in rolling-circle amplification embodiments was devised. This entailed the affinity purification of circular DNA templates before amplification.


Subject(s)
DNA Polymerase I/genetics , Geobacillus stearothermophilus/genetics , Nucleic Acid Amplification Techniques/methods , Base Sequence , Cloning, Molecular , DNA Primers , DNA, Bacterial/analysis , DNA, Circular/isolation & purification , Escherichia coli , Geobacillus stearothermophilus/enzymology , Indicators and Reagents , Molecular Sequence Data , Sensitivity and Specificity , Streptavidin
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