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1.
Phys Rev Lett ; 128(14): 149901, 2022 Apr 08.
Article in English | MEDLINE | ID: mdl-35476499

ABSTRACT

This corrects the article DOI: 10.1103/PhysRevLett.125.163001.

2.
Phys Rev Lett ; 125(16): 163001, 2020 Oct 16.
Article in English | MEDLINE | ID: mdl-33124859

ABSTRACT

We report on the first coherent excitation of the highly forbidden ^{2}S_{1/2}→^{2}F_{7/2} electric octupole (E3) transition in a single trapped ^{172}Yb^{+} ion, an isotope without nuclear spin. Using the transition in ^{171}Yb^{+} as a reference, we determine the transition frequency to be 642 116 784 950 887.6(2.4) Hz. We map out the magnetic field environment using the forbidden ^{2}S_{1/2}→^{2}D_{5/2} electric quadrupole (E2) transition and determine its frequency to be 729 476 867 027 206.8(4.4) Hz. Our results are a factor of 1×10^{5} (3×10^{5}) more accurate for the E2 (E3) transition compared to previous measurements. The results open up the way to search for new physics via precise isotope shift measurements and improved tests of local Lorentz invariance using the metastable ^{2}F_{7/2} state of Yb^{+}.

3.
Phys Rev Lett ; 122(25): 253401, 2019 Jun 28.
Article in English | MEDLINE | ID: mdl-31347879

ABSTRACT

We report on the observation of interactions between ultracold Rydberg atoms and ions in a Paul trap. The rate of observed inelastic collisions, which manifest themselves as charge transfer between the Rydberg atoms and ions, exceeds that of Langevin collisions for ground state atoms by about 3 orders of magnitude. This indicates a huge increase in interaction strength. We study the effect of the vacant Paul trap's electric fields on the Rydberg excitation spectra. To quantitatively describe the exhibited shape of the ion loss spectra, we need to include the ion-induced Stark shift on the Rydberg atoms. Furthermore, we demonstrate Rydberg excitation on a dipole-forbidden transition with the aid of the electric field of a single trapped ion. Our results confirm that interactions between ultracold atoms and trapped ions can be controlled by laser coupling to Rydberg states. Adding dynamic Rydberg dressing may allow for the creation of spin-spin interactions between atoms and ions, and the elimination of collisional heating due to ionic micromotion in atom-ion mixtures.

4.
Phys Rev Lett ; 118(26): 263201, 2017 Jun 30.
Article in English | MEDLINE | ID: mdl-28707930

ABSTRACT

We theoretically study trapped ions that are immersed in an ultracold gas of Rydberg-dressed atoms. By off-resonant coupling on a dipole-forbidden transition, the adiabatic atom-ion potential can be made repulsive. We study the energy exchange between the atoms and a single trapped ion and find that Langevin collisions are inhibited in the ultracold regime for these repulsive interactions. Therefore, the proposed system avoids recently observed ion heating in hybrid atom-ion systems caused by coupling to the ion's radio frequency trapping field and retains ultracold temperatures even in the presence of excess micromotion.

5.
MMW Fortschr Med ; 149(4): 29, 31-2, 2007 Jan 25.
Article in German | MEDLINE | ID: mdl-17615713

ABSTRACT

Personal contact with a hospital and patients who have received treatment there offer the best opportunity to assess its quality. A certification merely shows that a quality management system has been implemented, but says nothing about the quality of the actual outcomes achieved. Quality reports aid the family doctor to make an estimate of departments with which he has not so far cooperated. Objective information regarding the quality of outcomes are considerably more difficult to obtain. There appears to be a correlation between large numbers of operations and the quality of the surgery. In this area, the physician is dependent on voluntary publication of performance reports.


Subject(s)
Quality Indicators, Health Care/standards , Surgery Department, Hospital/standards , Thyroidectomy/standards , Cooperative Behavior , Germany , Humans , Information Storage and Retrieval , Internet , Outcome and Process Assessment, Health Care/standards , Patient Care Team/standards , Postoperative Complications/etiology , Quality Assurance, Health Care/standards
6.
Eur J Surg Oncol ; 32(3): 329-34, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16414234

ABSTRACT

AIMS: To analyse the outcome of patients with pT1 NSCLC treated at our institution by antero-lateral thoracotomy, anatomical lung resections and mediastinal lymph node dissection between 1980 and 2001. METHODS: Follow-up data were obtained retrospectively from 1980 to 1990 and prospectively after 1990. Survival was analysed using the Kaplan-Meier method. RESULTS: Histopathological examinations revealed mediastinal lymph node infiltration in 27.6% (pN1 17.8% and pN2 9.8%). pN2 was classified in 14.1% of adenocarcinomas compared to 6.2% of squamous cell carcinomas. Median overall survival of patients with pT1 carcinomas was 89+16 months (median+standard error). Histopathological N-classification indicates differential prognostic and therapeutic implications in pT1 adeno- and squamous cell carcinomas. CONCLUSIONS: Complete lymph node dissection is required for all patients with T1 NSCLC treated by either open surgery or VATS resection. Histopathological N-classification indicates differential prognostic and therapeutic implications in pT1 adeno- and squamous cell carcinomas.


Subject(s)
Carcinoma, Non-Small-Cell Lung/surgery , Lung Neoplasms/surgery , Pneumonectomy/methods , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Female , Follow-Up Studies , Humans , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Prospective Studies , Retrospective Studies , Survival Rate , Time Factors , Treatment Outcome
7.
Chirurg ; 75(8): 794-8, 2004 Aug.
Article in German | MEDLINE | ID: mdl-15007528

ABSTRACT

AIM: In a retrospective study, the sensitivity of parathyroid scintigraphy and ultrasound was investigated in patients with primary hyperparathyroidism (HPT) with prior histories of surgery of the thyroid or parathyroid (unsuccessful or recidive). METHODS: Preoperative ultrasound and parathyroid scintigraphy were performed on 65 patients who had had successful surgery and on 12 who had had unsuccessful surgery. The scintigraphy was carried out using a combined double phase/double nuclide technique with 300-600 MBq 99mTc-sestamibi for parathyroid imaging and 80-100 MBq 99mTc-pertechnetate for thyroid imaging. RESULTS: The sensitivity of parathyroid scintigraphy was 86% in patients with normal thyroid glands, 77% in those with recurrent goiter, and 62% in those with recurrent or persistent HPT. The ultrasound sensitivity was 86%, 50%, and 57% respectively. CONCLUSION: The sensitivity of parathyroid scintigraphy and ultrasound decreases considerably after surgery. That of parathyroid scintigraphy lay significantly below results published to date. However, parathyroid scintigraphy should be performed precisely in these cases, because the number of alternative parathyroid imaging methods aside from ultrasound are limited.


Subject(s)
Hyperparathyroidism/diagnosis , Parathyroid Glands/diagnostic imaging , Adult , Aged , Aged, 80 and over , Female , Goiter/surgery , Humans , Hyperparathyroidism/diagnostic imaging , Hyperparathyroidism/surgery , Male , Middle Aged , Parathyroid Glands/surgery , Postoperative Period , Preoperative Care , Recurrence , Retrospective Studies , Sensitivity and Specificity , Sodium Pertechnetate Tc 99m , Technetium Tc 99m Sestamibi , Thyroid Gland/diagnostic imaging , Thyroid Gland/surgery , Time Factors , Tomography, Emission-Computed, Single-Photon , Ultrasonography
8.
Urologe A ; 42(9): 1230-7, 2003 Sep.
Article in German | MEDLINE | ID: mdl-14504756

ABSTRACT

Based on a large single-center follow-up database, we evaluated the long-term results after curative resection of pulmonary metastases from renal cancer. During a 20-year period, 105 patients underwent a total of 150 resections with curative intention. Hospital mortality was 0.95%, 5- and 10-year survival rates were 40% and 33%, respectively. Significant prognostic relevance was shown for complete pulmonary resection, lymph node involvement upon primary resection as well as size of the resected lung metastasis. Our findings of low perioperative morbidity and mortality rates lead us to propose that in patients without additional metastases curative resection of pulmonary lesions should be considered. Moreover, recurrent pulmonary metastases should also be considered for surgical treatment since resection for cure significantly improves survival in these patients.


Subject(s)
Kidney Neoplasms/epidemiology , Lung Neoplasms/mortality , Lung Neoplasms/surgery , Adult , Aged , Female , Follow-Up Studies , Germany/epidemiology , Humans , Lung Neoplasms/secondary , Lymphatic Metastasis , Male , Middle Aged , Prognosis , Survival , Survival Analysis
9.
Langenbecks Arch Surg ; 387(3-4): 125-9, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12172856

ABSTRACT

AIMS: This study evaluated the techniques and short-term results of surgical treatment for esophageal cancer in Germany by a nationwide representative survey. METHODS: In 2000 a questionnaire including 63 structured items concerning indication, technique, number of procedures, complications, and hospital mortality was sent to 308 randomly selected general, gastrointestinal, and thoracic surgeons and all university hospitals in Germany (20% of all surgeons). The response rate was 76% ( n=234). RESULTS: In 1999 the 56 participating hospitals performed approximately 370,000 procedures, including 1,677 operations for esophageal diseases, including 891 esophagectomies, 706 for esophageal cancer, 285 for cancer of the cardia. Gastric interposition was the most common technique to restore alimentary tract continuity (86%). Interposition of the colon (ascending colon 64%) is a common procedure only in 22 centers, indicating that experience with this means of esophageal reconstruction is limited. There were no significant differences in complication and mortality rates between gastric transposition and colon interposition. The overall complication rate was 61%, with 36% after gastric interposition and 42% after colon interposition. Anastomotic leakages occurred in 12% and 15%, respectively, and the rate of graft necrosis was 3% in both groups. Hospital mortality was 8% with gastric transposition and 11% with colon interposition. Mean postoperative hospital stay was 24 days. CONCLUSIONS: This study indicates that gastric transposition is frequently used for reconstruction after esophageal resection for malignant disease. It appears that the colon is not as accepted as the stomach for reconstruction, although the reported complication rates compare well with those reported after gastric transposition. This study allows a realistic evaluation of the overall risk of these surgical techniques.


Subject(s)
Colon/surgery , Esophageal Neoplasms/surgery , Esophagectomy/methods , Esophagoplasty/methods , Stomach/surgery , Anastomosis, Surgical/adverse effects , Anastomosis, Surgical/methods , Anastomosis, Surgical/statistics & numerical data , Esophageal Neoplasms/mortality , Esophagectomy/adverse effects , Esophagectomy/statistics & numerical data , Esophagoplasty/adverse effects , Esophagoplasty/statistics & numerical data , Germany/epidemiology , Hospital Mortality , Hospitals, University , Humans , Length of Stay/statistics & numerical data , Risk Factors , Surveys and Questionnaires , Treatment Outcome
10.
Eur Respir J ; 20(1): 165-9, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12166565

ABSTRACT

Obliterative bronchiolitis is commonly interpreted as chronic rejection and involves the bronchial and bronchiolar epithelium. Upregulation of major histocompatibility complex (MHC) II on bronchial epithelial cells (BEC) had been hypothesised to be an important trigger of a bronchus directed rejection response. More recently, the additional expression of the costimulatory molecules B7-1 (CD80) and B7-2 (CD86) on antigen presenting cells were found to play an important role in the activation of T-lymphocytes in transplant rejection. The role of the expression of these molecules by BEC is unclear. BEC obtained by bronchial brushing and bronchoalveolar lavage fluid (BALF) cells from lung transplant recipients were studied and evaluated for messenger ribonucleic acid (mRNA) expression of B7-1 and B7-2 by semi-quantitative reverse transcriptase-polymerase chain reaction. Significantly elevated B7-1/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA ratios were found in BEC from patients examined during the first 3 months after lung transplantation. Interestingly, in a small group of patients with bronchiolitis obliterans syndrome the B7-1/GAPDH and B7-2/GAPDH ratios were significantly elevated for BEC, whereas no differences were found for the BALF cells. In summary, B7 messenger ribonucleic acid expression by bronchial epithelial cells may play a role in (chronic) lung allograft rejection.


Subject(s)
Antigens, CD/analysis , Antigens, CD/genetics , B7-1 Antigen/analysis , B7-1 Antigen/genetics , Bronchi/pathology , Bronchiolitis Obliterans/etiology , Bronchiolitis Obliterans/genetics , Bronchoalveolar Lavage Fluid/cytology , Epithelial Cells/pathology , Gene Expression/genetics , Graft Rejection/etiology , Graft Rejection/genetics , Lung Transplantation/adverse effects , Membrane Glycoproteins/analysis , Membrane Glycoproteins/genetics , RNA, Messenger/analysis , RNA, Messenger/genetics , Adult , B7-2 Antigen , Bronchiolitis Obliterans/pathology , Female , Glyceraldehyde-3-Phosphate Dehydrogenases/analysis , Glyceraldehyde-3-Phosphate Dehydrogenases/genetics , Graft Rejection/pathology , Humans , Lung Transplantation/pathology , Male , Middle Aged
12.
Handchir Mikrochir Plast Chir ; 34(1): 65-8, 2002 Jan.
Article in German | MEDLINE | ID: mdl-11898058

ABSTRACT

Free jejunal grafts are the method of choice for one-stage reconstruction of the hypopharynx and the upper esophagus. Prerequisites for a successful free transplantation are a sufficient arterial vascularisation and a corresponding venous drainage. In a 59-year old patient, an esophagectomy was performed because of a proximal esophageal cancer. The passage was primarily reconstructed by a pedicled colon interposition. Necrosis of the cranial graft occurred. After resection of the necrotic bowel, a free jejunal graft was introduced thoraco-cervically. The nutrient vessels of the graft were anastomosed to the upper thyroid artery and the vena thyroid ima. In an operative revision one day postoperatively due to lacking re-capillarisation, the arterial inflow stopped. The superior thyroid artery was cut at its cranial origin at the external carotid artery and microsurgically implanted into the common carotid artery. Hereafter, a venous outflow was re-established. But the critical time of ischaemia was exceeded. In another operative revision, the cephalic vein was exposed at the cranial upper arm, distally cut and anastomosed to the re-implanted superior thyroid artery. After the harvest of a second autogenous jejunal graft, the arterio-venous shunt was cut and the segments were anastomosed to the mesenterial artery and vein. Transpositions of arteries and veins with temporary formation of an arterio-venous shunt may be prerequisites for a sufficient vascularisation and can enable a successful free microsurgical transplantation even in critical vascular situations.


Subject(s)
Esophageal Neoplasms/surgery , Esophagectomy , Jejunum/transplantation , Microsurgery , Postoperative Complications/surgery , Surgical Flaps/blood supply , Anastomosis, Surgical , Arteries/surgery , Colon/transplantation , Humans , Jejunum/blood supply , Male , Middle Aged , Reoperation , Veins/surgery
13.
Eur Surg Res ; 34(1-2): 77-82, 2002.
Article in English | MEDLINE | ID: mdl-11867906

ABSTRACT

BACKGROUND: Reperfusion injury represents a severe early complication following lung transplantation. Among the pathogenetic factors, the high potassium content of Euro-Collins(reg) solution is discussed. MATERIAL AND METHODS: In a pig model of orthotopic left-sided lung transplantation we investigated the effect of Euro-Collins solution (EC: n = 6) versus low potassium dextran (LPD: Perfadex: n = 6). Sham-operated (n = 6) animals served as control. Transplant function, cellular energy metabolism and endothelial morphology served as parameters. In a clinical investigation, 124 patients were evaluated following single (EC: n = 31; LPD n = 37) or double (EC: n = 17; LPD n = 39) lung transplantation, whose organs where preserved with EC (n = 48) or LPD (n = 76). Duration of ischemia, duration of ventilation and stay on ICU were registered. Primary transplant function was evaluated according to AaDO(2) values. Cause of early death (30 days) was declared. RESULTS: Experimental results: After flush with EC and 18 h ischemia, a reduction of tissue ATP content (p < 0.01 vs inital value and LPD) was noted. Endothelial damage after ischemia was severe (p < 0.05 vs control), paO(2) was significantly decreased. CLINICAL RESULTS: In the LPD group, duration of ischemia was longer for the grafts transplanted first (SLTx and DLTx: p = 0.0009) as well as second (2. organ DLTx: p = 0.045). Primary transplant function was improved (day 0: SLTx: p = 0.0015; DLTx: p = 0.0095, both vs EC). Duration of ventilation and stay on ICU were shorter (n.s.). Reperfusion injury-associated death was reduced from 8% (EC) to 0 (LPD). CONCLUSION: In experimental lung preservation, LPD lead to an improved graft function. These results were confirmed in clinical lung transplantation. Clinical lung preservation, therefore, should be carried out by use of LPD.


Subject(s)
Dextrans/therapeutic use , Glucose/therapeutic use , Hypertonic Solutions/therapeutic use , Lung Transplantation/methods , Organ Preservation Solutions/therapeutic use , Reperfusion Injury/drug therapy , Adult , Animals , Female , Humans , Lung/physiology , Lung Diseases/surgery , Male , Middle Aged , Reperfusion Injury/mortality , Reperfusion Injury/prevention & control , Swine
14.
World J Surg ; 25(8): 969-74, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11571977

ABSTRACT

"Silent" cerebral infarction is found in 20% to 30% of patients with significant internal carotid artery (ICA) disease. Our purpose was to determine whether such "silent" cerebral infarction in the operated carotid territory represents a risk factor for stroke during and immediately after carotid endarterectomy. Over 5 years we followed a cohort of 663 patients with symptomatic and asymptomatic ICA stenosis who were consecutively scheduled for surgery. The stenosis was more than 70% in patients with transient ischemic attacks and more than 95% in asymptomatic stenosis patients. All patients underwent preoperative computed tomography to determine the frequency, extent, and location of any "silent" cerebral infarction. Patients were grouped by the absence or presence of infarction in the operated carotid territory. Among the entire cohort, 20 patients had a major perioperative stroke (3.0%). All deaths were stroke-related. No intracranial bleeding occurred. Major stroke occurred in four (0.8%) patients without appropriate "silent" cerebral infarction, compared with 16 (8.8%) with an appropriate "silent" cerebral infarct (p < 0.001). After adjustment for confounding co-variables (e.g., gender, presence of preoperative symptoms, and age), "silent" cerebral infarction was found to be the only independent predictor of perioperative major stroke for symptomatic and asymptomatic stenosis (overall adjusted relative risk 11.5, 95% confidence interval 3.8-34.9, p < 0.0001). Patients with "silent" cerebral infarction seem to be at increased risk of perioperative stroke. Consequently, preoperative cerebral imaging is important for risk classification.


Subject(s)
Cerebral Infarction/complications , Endarterectomy, Carotid/adverse effects , Stroke/etiology , Aged , Female , Humans , Male , Prospective Studies , Risk Factors , Stroke/epidemiology
15.
Dis Esophagus ; 14(2): 131-4, 2001.
Article in English | MEDLINE | ID: mdl-11553223

ABSTRACT

Preliminary results of a questionnaire survey showed that gastric transposition is the technique of choice in Germany to restore alimentary continuity after esophageal resection. Experience with colon interposition grafting is low. Only 13% of all centers perform this technique. Despite this limited experience, there appears to be no difference in the complication rate between gastric pull-through procedures and colon interpositions. A modification of established colon interposition techniques is possible when the right colon is used if it is prepared in such a way that the left colonic artery is the blood supplying vessel. This modified technique may be simpler to perform than previous procedures for creating a colon interposition graft and may also facilitate esophageal replacement using colon interposition grafting.


Subject(s)
Colon/transplantation , Esophageal Neoplasms/surgery , Esophagectomy/methods , Esophagus/surgery , Anastomosis, Surgical , Carcinoma, Squamous Cell/surgery , Colon/blood supply , Germany , Humans , Postoperative Complications , Surveys and Questionnaires , Transplantation, Autologous
16.
Clin Chem Lab Med ; 39(7): 596-605, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11522104

ABSTRACT

The concentration of nucleosomes is elevated in blood of patients with diseases which are associated with enhanced cell death. In order to detect these circulating nucleosomes, we used the Cell Death Detection-ELISAplus (CDDE) from Roche Diagnostics (Mannheim, Germany) (details at http:\\biochem.roche.com). For its application in liquid materials we performed various modifications: we introduced a standard curve with nucleosome-rich material, which enabled direct quantification and improved comparability of the values within (CVintraassay:3.0-4.11%) and between several runs (CVinterassay:8.6-13.5%), and tested the analytical specificity of the ELISA. Because of the fast elimination of nucleosomes from circulation and their limited stability, we compared plasma and serum matrix and investigated in detail the pre-analytical handling of serum samples which can considerably influence the test results. Careless venipuncture producing hemolysis, delayed centrifugation and bacterial contamination of the blood samples led to false-positive results; delayed stabilization with EDTA and insufficient storage conditions resulted in false-negative values. At temperatures of -20 degrees C, serum samples which were treated with 10 mM EDTA were stable for at least 6 months. In order to avoid possible interfering factors, we recommend a schedule for the pre-analytical handling of the samples. As the first stage, the possible clinical application was investigated in the sera of 310 persons. Patients with solid tumors (n=220; mean=361 Arbitrary Units (AU)) had considerably higher values than healthy persons (n=50; mean=30 AU; p=0.0001) and patients with inflammatory diseases (n=40; mean= 296 AU; p=0.096). Within the group of patients with tumors, those in advanced stages (UICC 4) showed significantly higher values than those in early stages (UICC 1-3) (p=0.0004).


Subject(s)
Biomarkers , Cell Death , Enzyme-Linked Immunosorbent Assay/methods , Nucleosomes/metabolism , Anti-Bacterial Agents/pharmacology , Antibodies/metabolism , Chemistry, Clinical/methods , Edetic Acid/pharmacology , Female , Histones/immunology , Humans , Inflammation/blood , Male , Neoplasms/blood , Specimen Handling , Time Factors
20.
Int J Cancer ; 95(2): 114-20, 2001 Mar 20.
Article in English | MEDLINE | ID: mdl-11241322

ABSTRACT

High quantities of mono- and oligonucleosomes circulate in the blood of patients with malignant tumors. For their direct quantification in serum, we modified the Cell Death Detection(plus)-ELISA for its application in liquid materials. We examined sera samples from 590 persons, including 418 patients with malignant tumors, 109 patients with benign diseases and 63 healthy persons. We also observed the kinetics of the concentration of nucleosomes in serum samples from 20 patients undergoing chemotherapy and from 16 patients undergoing radiotherapy. Sera of patients with malignant tumors contained considerably higher concentrations of nucleosomes (mean = 350 arbitrary units [AU], median = 190 AU) compared with those of healthy persons (mean = 36 AU, median = 24 AU; p = 0.0001) and patients with benign diseases (mean = 264 AU, median = 146 AU; p = 0.072). Concerning the follow-up investigations, the concentration of nucleosomes in serum increased 24-72 hr after the first application of chemotherapy and 6-24 hr after the start of radiotherapy. A subsequent decrease was often correlated with regression of the tumor. In patients undergoing chemotherapy, an increase in the baseline values of circulating nucleosomes >50%, which were determined before each new therapeutic cycle, was correlated with progression of disease; all patients with disease regression showed a decrease >50% of the baseline values. In patients undergoing radiotherapy, an early decrease of the nucleosomal concentration (< or = 1 day after the initial peak during therapy) to low minimum levels (< or = 100 AU) correlated with good clinical outcome; a late decrease (>1 day) to higher minimum levels (>100 AU) was associated with a worse clinical outcome. Thus, the concentration of nucleosomes in serum might be a useful tool for monitoring the biochemical response during antitumor therapy, especially for the early estimation of therapeutic efficacy.


Subject(s)
Neoplasms/blood , Nucleosomes/chemistry , Nucleosomes/metabolism , Cell Death , Cell Membrane/metabolism , Enzyme-Linked Immunosorbent Assay , Female , Humans , Kinetics , Male , Neoplasms/drug therapy , Neoplasms/radiotherapy , Time Factors , Treatment Outcome
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