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1.
Nat Commun ; 15(1): 223, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38172154

ABSTRACT

The heavy fermion paramagnet UTe2 exhibits numerous characteristics of spin-triplet superconductivity. Efforts to understand the microscopic details of this exotic superconductivity have been impeded by uncertainty regarding the underlying electronic structure. Here we directly probe the Fermi surface of UTe2 by measuring magnetic quantum oscillations in pristine quality crystals. We find an angular profile of quantum oscillatory frequency and amplitude that is characteristic of a quasi-2D Fermi surface, which we find is well described by two cylindrical Fermi sheets of electron- and hole-type respectively. Additionally, we find that both cylindrical Fermi sheets possess considerable undulation but negligible small-scale corrugation, which may allow for their near-nesting and therefore promote magnetic fluctuations that enhance the triplet pairing mechanism. Importantly, we find no evidence for the presence of any 3D Fermi surface sections. Our results place strong constraints on the possible symmetry of the superconducting order parameter in UTe2.

2.
Nat Commun ; 9(1): 3699, 2018 09 07.
Article in English | MEDLINE | ID: mdl-30194428

ABSTRACT

This article contains errors in Figs. 5 and 6, for which we apologize. In Fig. 5f, the image 'E12.5 tail' was inadvertently replaced with a duplicate of the image 'E12.5 trunk' from the same panel. In Figure 6d, the image 'E9.5/OH-TAM E8.5, embryo' was inadvertently replaced with a duplicate of the image 'E10.5/ OH-TAM E8.5, embryo' from Fig. 6b. The corrected versions of these figures appear in the Author Correction associated with this Article.

3.
J Immunol Methods ; 457: 66-72, 2018 06.
Article in English | MEDLINE | ID: mdl-29630967

ABSTRACT

Allogeneic bone marrow (BM) transplantation enables the in vivo functional assessment of hematopoietic cells. As pre-conditioning, ionizing radiation is commonly applied to induce BM depletion, however, it exerts adverse effects on the animal and can limit experimental outcome. Here, we provide an alternative method that harnesses conditional gene deletion to ablate c-myb and thereby deplete BM cells, hence allowing BM substitution without other pre-conditioning. The protocol results in a high level of blood chimerism after allogeneic BM transplantation, whereas immune cells in peripheral tissues such as resident macrophages are not replaced. Further, mice featuring a low chimerism after initial transplantation can undergo a second induction cycle for efficient deletion of residual BM cells without the necessity to re-apply donor cells. In summary, we present an effective c-myb-dependent genetic technique to generate BM chimeras in the absence of irradiation or other methods for pre-conditioning.


Subject(s)
Bone Marrow Transplantation/methods , Gene Deletion , Genes, myb/genetics , Hematopoietic Stem Cell Transplantation/methods , Transplantation Chimera , Animals , Female , Immune Tolerance , Male , Mice , Mice, Inbred C57BL , Poly I-C/administration & dosage , Radiation, Ionizing , Transplantation Conditioning , Transplantation, Homologous
4.
Nat Commun ; 9(1): 75, 2018 01 08.
Article in English | MEDLINE | ID: mdl-29311541

ABSTRACT

Tissue macrophages in many adult organs originate from yolk sac (YS) progenitors, which invade the developing embryo and persist by means of local self-renewal. However, the route and characteristics of YS macrophage trafficking during embryogenesis are incompletely understood. Here we show the early migration dynamics of YS-derived macrophage progenitors in vivo using fate mapping and intravital microscopy. From embryonic day 8.5 (E8.5) CX3CR1+ pre-macrophages are present in the mouse YS where they rapidly proliferate and gain access to the bloodstream to migrate towards the embryo. Trafficking of pre-macrophages and their progenitors from the YS to tissues peaks around E10.5, dramatically decreases towards E12.5 and is no longer evident from E14.5 onwards. Thus, YS progenitors use the vascular system during a restricted time window of embryogenesis to invade the growing fetus. These findings close an important gap in our understanding of the development of the innate immune system.


Subject(s)
Cell Movement , Embryonic Stem Cells/cytology , Macrophages/cytology , Yolk Sac/cytology , Animals , Blood Circulation , Cell Lineage , Cell Proliferation , Embryo, Mammalian/blood supply , Embryo, Mammalian/cytology , Embryo, Mammalian/embryology , Hematopoietic Stem Cells/cytology , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Microscopy, Confocal , Time Factors , Yolk Sac/embryology
5.
Am J Med ; 109(1): 9-14, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10936472

ABSTRACT

PURPOSE: Herbal medicines are widely used for the treatment of pain, although there is not much information on their effectiveness. This study was designed to evaluate the effectiveness of willow (Salix) bark extract, which is widely used in Europe, for the treatment of low back pain. SUBJECTS AND METHODS: We enrolled 210 patients with an exacerbation of chronic low back pain who reported current pain of 5 or more (out of 10) on a visual analog scale. They were randomly assigned to receive an oral willow bark extract with either 120 mg (low dose) or 240 mg (high dose) of salicin, or placebo, with tramadol as the sole rescue medication, in a 4-week blinded trial. The principal outcome measure was the proportion of patients who were pain-free without tramadol for at least 5 days during the final week of the study. RESULTS: The treatment and placebo groups were similar at baseline in 114 of 120 clinical features. A total of 191 patients completed the study. The numbers of pain-free patients in the last week of treatment were 27 (39%) of 65 in the group receiving high-dose extract, 15 (21%) of 67 in the group receiving low-dose extract, and 4 (6%) of 59 in the placebo group (P <0.001). The response in the high-dose group was evident after only 1 week of treatment. Significantly more patients in the placebo group required tramadol (P <0.001) during each week of the study. One patient suffered a severe allergic reaction, perhaps to the extract. CONCLUSION: Willow bark extract may be a useful and safe treatment for low back pain.


Subject(s)
Benzyl Alcohols/therapeutic use , Low Back Pain/drug therapy , Plant Extracts/therapeutic use , Administration, Oral , Adolescent , Adult , Aged , Analgesics, Opioid/therapeutic use , Chronic Disease , Double-Blind Method , Female , Glucosides , Humans , Low Back Pain/physiopathology , Male , Middle Aged , Pain Measurement , Prospective Studies , Tramadol/therapeutic use
6.
Eur J Orthod ; 22(2): 169-74, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10822890

ABSTRACT

Katz's quantitative modification of Angle's occlusion classification has been found to have a high intra- and inter-examiner agreement among orthodontists. In the present study an attempt was made to introduce a 'combined' system comprising Katz's modification and overjet/overbite millimetric measurements in order to attain a more meaningful and complete classification of malocclusion than is presently available. A group of 32 raters (16 orthodontists and 16 senior-year students) examined 14 study models twice, with an interval of at least 1 month between examinations. In total, 448 x 2 determinations were performed. The percentage agreement of the Angle, the modified and the 'combined' systems, as well as the performance of the orthodontists versus the students were compared using the paired t-test. The percentage agreement obtained by both orthodontists and students was highest for Katz's modification and lowest for Angle's method. The overjet/overbite measurements affected the agreement in Katz's modified technique. The orthodontists surpassed the students with respect to Angle's method (P = 0.025), whereas no statistically significant difference existed between orthodontists and students regarding Katz's modification or the 'combined' system. It is concluded that in view of the relatively low agreement in the 'combined' method, it cannot be recommended for clinical application. The Katz's modified method, on the other hand, may be a helpful supplement to Angle's classification.


Subject(s)
Dental Occlusion , Malocclusion/classification , Cephalometry , Humans , Incisor/pathology , Malocclusion/pathology , Malocclusion, Angle Class II/classification , Malocclusion, Angle Class III/classification , Models, Dental , Observer Variation , Orthodontics/education , Pilot Projects , Statistics as Topic , Students, Dental
7.
Ann Emerg Med ; 35(1): 3-10, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10613934

ABSTRACT

STUDY OBJECTIVE: Advanced cardiac life support (ACLS) guidelines recommend a 3- to 5-minute interval between repeated doses of epinephrine. This recommendation does not take into account the dose of epinephrine used, and only very limited data exist regarding the hemodynamic responses to repeated "high" doses of epinephrine. The objective of this study was to analyze the hemodynamic responses to repeated, equal, high doses of epinephrine administered during cardiopulmonary resuscitation (CPR) in a canine model of ventricular fibrillation (VF). METHODS: This study used a secondary analysis of data collected in a prospective, randomized study, primarily designed to assess the effects of acid buffers in a canine model of cardiac arrest. VF was electrically induced. After 10 minutes, CPR was initiated, including ventilation with FIO(2)=1.0, external chest compressions, administration of epinephrine (0.1 mg/kg repeated every 5 minutes) and defibrillation. Animals were randomized to receive either NaHCO(3), Carbicarb, tromethamine (THAM), or NaCl. The hemodynamic variables were sampled from each experiment's paper chart at 1-minute intervals, and the responses to the first 4 doses of epinephrine were compared. RESULTS: Thirty-six animals (9 in each buffer group) were included in this analysis. Systolic, diastolic, and coronary perfusion pressures increased steeply (by 100%, 130%, and 190%, respectively) only after the first epinephrine dose. These pressures peaked at 2 to 3 minutes and decreased only slightly and insignificantly during the rest of the 5-minute interval, until the next epinephrine dose. No further significant increases in arterial pressures were observed in response to the next 3 doses of epinephrine, administered 5 minutes apart. CONCLUSION: The hemodynamic effects of high-dose epinephrine (0.1 mg/kg) during CPR appear to last longer than 5 minutes. Therefore, longer intervals between doses may be justified with high doses of epinephrine.


Subject(s)
Adrenergic alpha-Agonists/administration & dosage , Blood Pressure/drug effects , Cardiopulmonary Resuscitation/methods , Epinephrine/administration & dosage , Vasoconstrictor Agents/administration & dosage , Ventricular Fibrillation/drug therapy , Ventricular Fibrillation/physiopathology , Adrenergic alpha-Agonists/pharmacology , Animals , Buffers , Carbonates/administration & dosage , Carbonates/pharmacology , Disease Models, Animal , Dogs , Drug Administration Schedule , Drug Combinations , Drug Evaluation, Preclinical , Drug Therapy, Combination , Epinephrine/pharmacology , Practice Guidelines as Topic , Random Allocation , Sodium Bicarbonate/administration & dosage , Sodium Bicarbonate/pharmacology , Sodium Chloride/administration & dosage , Sodium Chloride/pharmacology , Time Factors , Tromethamine/administration & dosage , Tromethamine/pharmacology , Vasoconstrictor Agents/pharmacology
9.
Crit Care Med ; 26(8): 1397-408, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9710100

ABSTRACT

OBJECTIVES: During cardiopulmonary resuscitation (CPR), elimination of CO2 was shown to be limited by low tissue perfusion, especially when very low perfusion pressures were generated. It has therefore been suggested that sodium bicarbonate (NaHCO3), by producing CO2, might aggravate the hypercarbic component of the existing acidosis and thereby worsen CPR outcome. The objectives of this study were to evaluate the effects of CO2 producing and non-CO2 producing buffers in a canine model of prolonged ventricular fibrillation followed by effective CPR. DESIGN: Prospective, randomized, controlled, blinded trial. SETTING: Experimental animal research laboratory in a university research center. SUBJECTS: Thirty-eight adult dogs, weighing 20 to 35 kg. INTERVENTIONS: Animals were prepared for study with thiopental followed by halothane, diazepam, and pancuronium. Ventricular fibrillation was electrically induced, and after 10 mins, CPR was initiated, including ventilation with an FIO2 of 1.0, manual chest compressions, administration of epinephrine (0.1 mg/kg every 5 mins), and defibrillation. A dose of buffer, equivalent to 1 mmol/kg of NaHCO3, was administered every 10 mins from start of CPR. Animals were randomized to receive either NaHCO3, Carbicarb, THAM, or 0.9% sodium chloride (NaCl). CPR was continued for up to 40 mins or until return of spontaneous circulation. MEASUREMENTS AND MAIN RESULTS: Buffer-treated animals had a higher resuscitability rate compared with NaCl controls. Spontaneous circulation returned earlier and at a significantly higher rate after NaHCO3 (in seven of nine dogs), and after Carbicarb (six of ten dogs) compared with NaCl controls (two of ten dogs). Spontaneous circulation was achieved twice as fast after NaHCO3 compared with NaCl (14.6 vs. 28 mins, respectively). Hydrogen ion (H+) concentration and base excess, obtained 2 mins after the first buffer dose, were the best predictors of resuscitability. Arterial and mixed venous Pco2 did not increase after NaHCO3 or Carbicarb compared with NaCl. CONCLUSIONS: Buffer therapy promotes successful resuscitation after prolonged cardiac arrest, regardless of coronary perfusion pressure. NaHCO3, and to a lesser degree, Carbicarb, are beneficial in promoting early return of spontaneous circulation. When epinephrine is used to promote tissue perfusion, there is no evidence for hypercarbic venous acidosis associated with the use of these CO2 generating buffers.


Subject(s)
Carbonates/administration & dosage , Cardiopulmonary Resuscitation , Heart Arrest/therapy , Sodium Bicarbonate/administration & dosage , Tromethamine/administration & dosage , Ventricular Fibrillation/therapy , Animals , Blood Gas Analysis , Buffers , Cardiopulmonary Resuscitation/methods , Disease Models, Animal , Dogs , Drug Combinations , Epinephrine/administration & dosage , Heart Arrest/mortality , Heart Arrest/physiopathology , Hemodynamics/drug effects , Infusions, Intravenous , Prospective Studies , Random Allocation , Treatment Outcome , Ventricular Fibrillation/mortality , Ventricular Fibrillation/physiopathology
11.
J Telemed Telecare ; 4 Suppl 1: 11-4, 1998.
Article in English | MEDLINE | ID: mdl-9640719

ABSTRACT

A primary-care teleconsulting system was established between an academic family medicine centre and a clinic about 50 km away. The videoconferencing units were connected at 384 kbit/s. Seven patients were examined by a physician in the clinic and then examined by a consulting physician using the telemedicine system. Four other patients were examined through the telemedicine system first and by a local physician later. The telemedicine consultation solved five of the patients' medical problems. The waiting period before receiving expert medical consultation was reduced. There was full patient satisfaction regarding this method of consultation, patient 'run around' was avoided and patients felt at ease. The telemedicine consultation process improved the patient-physician bond and the attending physician's level of confidence.


Subject(s)
Primary Health Care/methods , Telemedicine/methods , Adult , Aged , Aged, 80 and over , Female , Heart Diseases/diagnosis , Humans , Israel , Male , Middle Aged , Sensitivity and Specificity , Skin Diseases/diagnosis , Teleradiology
12.
Harefuah ; 134(10): 767-9, 831, 1998 May 15.
Article in Hebrew | MEDLINE | ID: mdl-10909634

ABSTRACT

We report a 48-year-old man admitted for watery diarrhea, high fever, chills and abdominal cramps. Enterohemorrhagic E. coli O157:H7 was isolated. This new, dangerous pathogen causes dysentery and complications such as hemolytic uremic syndrome and thrombotic thrombocytopenic purpura. These complications can cause renal failure, neurological deficit and death. Recognition of E. coli O157:H7 infection is important since it causes a rare and dangerous condition. To the best of our knowledge this is the first case reported in Israel.


Subject(s)
Escherichia coli Infections/diagnosis , Escherichia coli O157 , Gastroenteritis/microbiology , Anti-Bacterial Agents/therapeutic use , Escherichia coli Infections/complications , Escherichia coli Infections/drug therapy , Humans , Male , Middle Aged
14.
Zentralbl Veterinarmed A ; 40(9-10): 757-78, 1993.
Article in German | MEDLINE | ID: mdl-8135083

ABSTRACT

Twenty adult warm blooded horses (body weight 585 +/- 59 kg) were evaluated with pulsed doppler echocardiography. Locations for the transducer and the sample volume were determined to get typical blood flow tracings of the equine heart. Angle of doppler beam was between 37 degrees and 40 degrees in right heart atrioventricular flow tract and between 44 degrees and 47 degrees in left heart atrioventricular flow tract. Peak blood flow velocity (angle corrected) was 0.71 +/- 0.17 m/s in tricuspid valve and 0.92 +/- 0.22 in mitral valve. In right and left atrioventricular flow tracts in all sample volume positions typical double peaked spectral tracings of blood flow were seen. In supravalvular, valvular and subvalvular sample volume locations of the ventriculoatrial flow tracts angles were between 28 degrees and 33 degrees in right heart and between 34 degrees and 37 degrees in left heart. Peak flow velocity (angle corrected) was 0.98 +/- 0.13 m/s in pulmonary valve and 0.92 +/- 0.09 m/s in aortic valve. Paradoxical systolic and diastolic flows were seen. The flow velocity tracings were similar to those found in man. Flow velocity values of clinically normal horses have a wide range like in healthy human beings. Nevertheless flow tracings of healthy horses have a characteristical profile and may be helpful in detecting abnormal blood flow in heart diseased horses.


Subject(s)
Coronary Circulation , Echocardiography, Doppler/veterinary , Horses/physiology , Animals , Blood Flow Velocity , Female , Male , Reference Values
17.
Zentralbl Veterinarmed A ; 39(9): 704-18, 1992 Nov.
Article in German | MEDLINE | ID: mdl-1455938

ABSTRACT

B- and M-mode echocardiography was performed on 38 horses. 34 patients had systolic heart murmur with the point of maximal intensity over mitral valve. Additionally, 17 of these patients were examined with the pulsed wave doppler echocardiography (Vingmed 200). In 26 patients with cardiac murmur and in 4 patients without cardiac murmur a mitral valve insufficiency was diagnosed by echocardiography. In 8 horses with a systolic murmur over mitral valve M- and B-mode evaluation could not reveal a haemodynamic importance of the murmur. The diagnosis of MVI was based on a dilation of left atrium with or without additional dilation of left ventricle on one hand and with a regurgitation of blood into left atrium found by pulsed wave doppler on the other hand. In 6 extremely dilated hearts a "real" ostium of regurgitation was detected as a direct echocardiographic finding in B-mode. Good correlations existed between echocardiographically evaluated changes of heart dimensions and autopsy measurements in 10 cases. The prognosis seems to be poor if systolic murmurs coincide with dilatation of left atrium and left ventricle, regurgitation of blood into left atrium or with a high degree dilation of left atrium without changes of left ventricle chamber size. In hearts with little to medium dilated left atrium without changes of left ventricle dimension and additionally a regurgitation into left atrium the prognosis seems at least to be cautious. Echocardiography is an available diagnostic help in evaluation of the importance of systolic murmur with the point of maximal intensity over the mitral valve especially in completion by pulsed wave doppler.


Subject(s)
Echocardiography, Doppler/veterinary , Echocardiography/veterinary , Heart Murmurs/veterinary , Horse Diseases/diagnostic imaging , Mitral Valve Insufficiency/veterinary , Animals , Heart Murmurs/diagnostic imaging , Heart Murmurs/etiology , Horses , Mitral Valve Insufficiency/complications , Mitral Valve Insufficiency/diagnostic imaging
18.
Can Fam Physician ; 30: 752, 1984 Apr.
Article in English | MEDLINE | ID: mdl-21279028
19.
ASDC J Dent Child ; 49(2): 142-4, 1982.
Article in English | MEDLINE | ID: mdl-6949939
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