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3.
J Intern Med ; 289(3): 325-339, 2021 03.
Article in English | MEDLINE | ID: mdl-32445216

ABSTRACT

BACKGROUND: Lemierre syndrome is characterized by head/neck vein thrombosis and septic embolism usually complicating an acute oropharyngeal bacterial infection in adolescents and young adults. We described the course of Lemierre syndrome in the contemporary era. METHODS: In our individual-level analysis of 712 patients (2000-2017), we included cases described as Lemierre syndrome if these criteria were met: (i) primary site of bacterial infection in the head/neck; (ii) objectively confirmed local thrombotic complications or septic embolism. The study outcomes were new or recurrent venous thromboembolism or peripheral septic lesions, major bleeding, all-cause death and clinical sequelae. RESULTS: The median age was 21 (Q1-Q3: 17-33) years, and 295 (41%) were female. At diagnosis, acute thrombosis of head/neck veins was detected in 597 (84%) patients, septic embolism in 582 (82%) and both in 468 (80%). After diagnosis and during in-hospital follow-up, new venous thromboembolism occurred in 34 (5.2%, 95% CI 3.8-7.2%) patients, new peripheral septic lesions became evident in 76 (11.7%; 9.4-14.3%). The rate of either was lower in patients who received anticoagulation (OR: 0.59; 0.36-0.94), higher in those with initial intracranial involvement (OR: 2.35; 1.45-3.80). Major bleeding occurred in 19 patients (2.9%; 1.9-4.5%), and 26 died (4.0%; 2.7-5.8%). Clinical sequelae were reported in 65 (10.4%, 8.2-13.0%) individuals, often consisting of cranial nerve palsy (n = 24) and orthopaedic limitations (n = 19). CONCLUSIONS: Patients with Lemierre syndrome were characterized by a substantial risk of new thromboembolic complications and death. This risk was higher in the presence of initial intracranial involvement. One-tenth of survivors suffered major clinical sequelae.


Subject(s)
Lemierre Syndrome/complications , Thromboembolism/etiology , Venous Thrombosis/etiology , Adolescent , Adult , Disease Progression , Female , Humans , Lemierre Syndrome/mortality , Male , Thromboembolism/mortality , Venous Thrombosis/mortality
4.
Ultramicroscopy ; 203: 60-67, 2019 08.
Article in English | MEDLINE | ID: mdl-30577954

ABSTRACT

Electron energy loss spectroscopy (EELS) in the electron microscope has progressed remarkably in the last five years. Advances in monochromator and spectrometer design have improved the energy resolution attainable in a scanning transmission electron microscope (STEM) to 4.2 meV, and new applications of ultrahigh energy resolution EELS have not lagged behind. They include vibrational spectroscopy in the electron microscope, a field that did not exist 5 years ago but has now grown very substantially. Notable examples include vibrational mapping with about 1 nm spatial resolution, analyzing the momentum dependence of vibrational states in very small volumes, determining the local temperature of the sample from the ratio of energy gains to energy losses, detecting hydrogen and analyzing its bonding, probing radiation-sensitive materials with minimized damage by aloof spectroscopy and leap-frog scanning, and identifying biological molecules with different isotopic substitutions. We review the instrumentation advances, provide a summary of key applications, and chart likely future directions.

5.
Phys Rev Lett ; 105(5): 051801, 2010 Jul 30.
Article in English | MEDLINE | ID: mdl-20867906

ABSTRACT

Scalar fields with a "chameleon" property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple weakly to the photon, they could be detectable through the afterglow effect of photon-chameleon-photon transitions. The ADMX experiment was used in the first chameleon search with a microwave cavity to set a new limit on scalar chameleon-photon coupling ßγ excluding values between 2×10(9) and 5×10(14) for effective chameleon masses between 1.9510 and 1.9525 µeV.

6.
Phys Rev Lett ; 104(4): 041301, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-20366699

ABSTRACT

Axions in the microeV mass range are a plausible cold dark-matter candidate and may be detected by their conversion into microwave photons in a resonant cavity immersed in a static magnetic field. We report the first result from such an axion search using a superconducting first-stage amplifier (SQUID) replacing a conventional GaAs field-effect transistor amplifier. This experiment excludes KSVZ dark-matter axions with masses between 3.3 microeV and 3.53 microeV and sets the stage for a definitive axion search utilizing near quantum-limited SQUID amplifiers.

7.
Phys Rev Lett ; 105(17): 171801, 2010 Oct 22.
Article in English | MEDLINE | ID: mdl-21231034

ABSTRACT

Hidden U(1) gauge symmetries are common to many extensions of the standard model proposed to explain dark matter. The hidden gauge vector bosons of such extensions may mix kinetically with standard model photons, providing a means for electromagnetic power to pass through conducting barriers. The axion dark matter experiment detector was used to search for hidden vector bosons originating in an emitter cavity driven with microwave power. We exclude hidden vector bosons with kinetic couplings χ>3.48×10⁻8 for masses less than 3 µeV. This limit represents an improvement of more than 2 orders of magnitude in sensitivity relative to previous cavity experiments.

10.
Laryngoscope ; 111(11 Pt 1): 1989-92, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11801984

ABSTRACT

OBJECTIVE: To evaluate the usefulness and accuracy of fine-needle aspiration cytology (FNAC) in the diagnosis of parotid gland masses. STUDY DESIGN: Retrospective chart review of patients undergoing FNAC. METHODS: Between January 1990 and December 1998, 410 parotid glands were resected at the Department of Otorhinolaryngology-Head and Neck Surgery at the University of Berne, Inselpital (Berne, Switzerland). Included in the study were 228 cases with preoperative FNAC. In a retrospective study the results of FNAC were analyzed and compared with the corresponding histopathological diagnosis. RESULTS: Histological evaluation revealed 65 malignant tumors and 163 benign lesions (150 neoplasms and 13 nonneoplastic lesions). The cytological findings were nondiagnostic in 13 (5.7%), true-negative in 146 (64%), true-positive in 39 (17%), false-negative in 22 (9.8%) and false-positive in 8 (4.5%) cases in detecting malignant tumors. Nineteen of 39 (49%) malignant tumors (true-positive) and 123 of 146 (84%) benign lesions (true-negative) were classified accurately. The accuracy, sensitivity, and specificity were 86%, 64%, and 95% respectively. CONCLUSIONS: Fine-needle aspiration cytology is a valuable adjunct to preoperative assessment of parotid masses. Preoperative recognition of malignant tumors may help prepare both the surgeon and patient for an appropriate surgical procedure.


Subject(s)
Parotid Diseases/pathology , Parotid Gland/pathology , Parotid Neoplasms/pathology , Biopsy, Needle , Female , Humans , Male , Middle Aged , Preoperative Care , Retrospective Studies , Sensitivity and Specificity
12.
Schweiz Med Wochenschr Suppl ; 116: 77S-79S, 2000.
Article in German | MEDLINE | ID: mdl-10780079

ABSTRACT

From 1992 to 1998, 105 patients of the Department of Otorhinolaryngology, Head and Neck Surgery in Berne underwent laryngectomy with primary implantation of a Provox prosthesis. These patients were followed up in an open prospective study and evaluated by the HRS scale, based on speaking ability and quality as well as on prosthesis care. 46 patients (44%) attained successful rehabilitation of the voice, defined as 12-15 points according to the HRS scale. Age, tumour stage and postoperative irradiation did not influence the results. Compared to the patient group with less than 12 HRS points, frequent replacements or short in situ lifetime of the prosthesis improve the results of rehabilitation. Patient compliance is an important factor in achieving success with the Provox prosthesis.


Subject(s)
Laryngeal Neoplasms/surgery , Laryngectomy/rehabilitation , Larynx, Artificial , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Prosthesis Design , Speech Production Measurement
13.
Schweiz Med Wochenschr ; Suppl 125: 35S-37S, 2000.
Article in German | MEDLINE | ID: mdl-11141935

ABSTRACT

Epiglottitis, commonly described as a paediatric disease, also occurs in adults. Early diagnosis and immediate treatment are crucial because of the rapid and possibly lethal course of upper airway obstruction due to swelling. Initial treatment consists in securing the upper airway and in antibiotic treatment. Streptococci and, especially in children, Haemophilus influenzae b are the most common bacteria. Our study focused on clinical and epidemiological changes since children started to be vaccinated against Haemophilus influenzae b in Switzerland (1992). We reviewed patient histories of 31 adults and 88 children who were hospitalised with epiglottitis at the University Hospital of Berne between 1989 and 1999. Our findings show that the incidence of epiglottitis in children, a clinically, epidemiologically and bacteriologically homogeneous disease, has dramatically decreased. Epiglottitis in adults presents as a more heterogeneous disease without change since the beginning of the vaccination programme. Due to the variety of germs it is impossible to recommend vaccination for adults against Haemophilus influenzae b.


Subject(s)
Bacterial Infections/complications , Epiglottitis/epidemiology , Adult , Child , Epiglottitis/diagnosis , Epiglottitis/microbiology , Haemophilus Infections/complications , Haemophilus Infections/prevention & control , Haemophilus Vaccines , Haemophilus influenzae , Humans , Incidence , Retrospective Studies , Streptococcal Infections/complications , Switzerland/epidemiology
14.
Schweiz Med Wochenschr ; Suppl 125: 77S-79S, 2000.
Article in German | MEDLINE | ID: mdl-11141947

ABSTRACT

Distortion product otoacoustic emissions (DPOAE) originate from nonlinear mechanical sound processing in the inner ear, mainly due to normal outer hair cell function. Outer hair cell impairment can be detected by means of DPOAE. With a special primary tone level paradigm which optimises the primary tone level difference over a wide stimulus level range (L1 = 0.4 L2 + 39 dB, L2 = 20 to 65 dB SPL, f2 = 0.5 to 8 kHz, f2/f1 = 1.2), DPOAE can be measured at levels close to the psychophysical hearing threshold. From the DPOAE growth functions, which are constructed from measurements at different stimulus levels, a DPOAE threshold can be defined (Boege et al., 1998), which can be interpreted as a threshold of mechanical processing by the outer hair cells. In this study, DPOAE thresholds were examined in 9 patients with reversible cochlear hearing loss, i.e. sudden deafness or noise trauma. With increasing hearing loss, low primary tone level DPOAE in particular decreased, and thus the DPOAE threshold increased. The DPOAE threshold makes it possible to detect mechanical sensitivity losses in a frequency-specific manner. Thus, loss of mechanical amplification may be differentiated from a non-mechanical cause of hearing loss.


Subject(s)
Audiometry , Auditory Threshold/physiology , Deafness/physiopathology , Hair Cells, Auditory, Outer/physiology , Hearing Loss, Noise-Induced/physiopathology , Otoacoustic Emissions, Spontaneous , Deafness/diagnosis , Hair Cells, Auditory, Outer/physiopathology , Hearing Loss, Noise-Induced/diagnosis , Humans
15.
Br J Clin Pharmacol ; 49(1): 72-9, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10606840

ABSTRACT

AIMS: Whereas cortical EEG effects of benzodiazepines are well characterized, information about benzodiazepine effects in other areas of the central nervous system is sparse. This study investigated the action of midazolam and its active metabolite alpha-hydroxy-midazolam on different parts of the auditory pathway in six healthy volunteers in a randomized, double-blind, three-way cross-over study. METHODS: Acoustically evoked short (SLP) and middle (MLP) latency potentials, transitory evoked otoacoustic emissions (TEOAE), and EEG power spectra were analysed after short i. v. injections of placebo, or 0.15 mg kg-1 midazolam, or alpha-hydroxy-midazolam, respectively. RESULTS: All subjects fell asleep during the 4 min infusion of active drug. SLP showed a significant transient increase of Jewett wave V 10 min after injection for midazolam and alpha-hydroxy-midazolam while the latency of wave I was unchanged. Both benzodiazepines induced a marked and long-lasting MLP amplitude decrease for 240 min with slow recovery over the following 360 min. No changes of TEOAE were observed. In agreement with earlier reports, increases in EEG beta activity and decreases in alpha activity were observed after administration of either drug. CONCLUSIONS: Systemically administered benzodiazepines modulate the auditory pathway above the level of the cochlea. While SLP changes were closely associated with sedation and high plasma benzodiazepine concentrations, MLP effects persisted for hours after sedation even at low benzodiazepine plasma levels. Evoked potentials may therefore be more sensitive than EEG as a tool to monitor benzodiazepine effects.


Subject(s)
Anti-Anxiety Agents/pharmacology , Electroencephalography/drug effects , Evoked Potentials, Auditory, Brain Stem/drug effects , Midazolam/analogs & derivatives , Adult , Anti-Anxiety Agents/pharmacokinetics , Audiometry, Pure-Tone , Auditory Pathways/drug effects , Cross-Over Studies , Double-Blind Method , Humans , Male , Midazolam/pharmacokinetics , Midazolam/pharmacology , Respiratory Mechanics/drug effects
16.
Ann Otol Rhinol Laryngol ; 108(5): 495-500, 1999 May.
Article in English | MEDLINE | ID: mdl-10335713

ABSTRACT

Monoclonal extramedullary plasmacytoma (EMP) is a rare, low-grade lymphoma found predominantly in the head and neck region. Only since the introduction of immunophenotyping techniques 2 decades ago has it been possible to differentiate EMP from benign polyclonal plasma cell proliferation. The purpose of this study was to trace the evolutionary profile of the disease under consideration of monoclonality assessment. The records of 24 patients with morphologically diagnosed EMP treated in a single institution underwent clinical and pathological review. Only 14 patients had true monoclonal plasmacytoma. No EMP-related deaths occurred. Two patients had local recurrence, and 2 patients developed multiple myeloma. Review of the literature confirms the low-grade malignancy of EMP. Diagnostic procedures must exclude benign polyclonal plasmacytoma, multiple myeloma, and solitary bone plasmacytoma. The slow natural progression of the disease and the rarity of secondary multiple myeloma favor nonmutilating local surgery whenever possible to avoid the long-term sequelae of radiotherapy.


Subject(s)
Head and Neck Neoplasms/pathology , Plasmacytoma/pathology , Adult , Aged , Aged, 80 and over , Antigens, CD/analysis , Female , Head and Neck Neoplasms/immunology , Head and Neck Neoplasms/therapy , Humans , Immunoglobulins/analysis , Immunophenotyping , Male , Middle Aged , Plasmacytoma/immunology , Plasmacytoma/therapy
17.
J Biomech ; 32(5): 485-91, 1999 May.
Article in English | MEDLINE | ID: mdl-10327002

ABSTRACT

Bone allograft material is treated with sterilization methods to prevent the transmission of diseases from the donor to the recipient. The effect of some of these treatments on the integrity of the bone is unknown. This study was performed to evaluate the effect of several sterilization methods on the mechanical behaviour of human middle ear bones. Due to the size and composition of the bones (approximately 1.5 mm diameter by 4 mm long), mechanical testing options were limited to the traditional platens compression test. Experiments were first performed with synthetic bone to evaluate the precision of this test applied to small specimens. Following this, fresh frozen human ossicles were thawed and sterilized with (i) 1 N NaOH (n = 12); (ii) 0.9% LpH, a phenolic solution (n = 12); or (iii) steam at 134 degrees C (n = 18). A group of 26 control specimens did not receive any sterilization treatment. Material and structural properties were determined from axial compression testing. Results from the synthetic bone showed that the test was reproducible, with standard deviations less than 20% of the means. Significant differences occurred in stiffness and ultimate force values between NaOH-treated and autoclaved bones when compared to normals (p<0.05), but not for LpH-treated bones. LpH is not approved for medical use, so NaOH is the most appropriate of the treatments studied for the sterilization of ossicle allografts.


Subject(s)
Ear Ossicles/physiology , Sterilization , Analysis of Variance , Biomechanical Phenomena , Bone Substitutes/chemistry , Cryopreservation , Disinfectants/pharmacology , Ear Ossicles/drug effects , Elasticity , Femur/drug effects , Femur/physiology , Glass/chemistry , Humans , Incus/drug effects , Incus/physiology , Malleus/drug effects , Malleus/physiology , Phenol/pharmacology , Reproducibility of Results , Sodium Hydroxide/pharmacology , Steam , Stress, Mechanical , Transplantation, Homologous
18.
Arch Otolaryngol Head Neck Surg ; 125(4): 417-22, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10208679

ABSTRACT

BACKGROUND: Apoptotic cell death plays a key role in the pathogenesis, aggressiveness, and therapy responsiveness of cancer. The suicidal machinery of apoptosis is genetically controlled. Proteins of the Bcl-2 family as well as p53 are important regulators of apoptosis. OBJECTIVE: To assess the rate of spontaneous apoptosis and the expression of p53 and Bcl-2 family proteins in locally advanced squamous cell carcinomas of the head and neck. DESIGN: Twenty-six patients with locally advanced squamous cell carcinoma of the head and neck were included in the study. The expression of p53, Bcl-2, Mcl-1, Bax, and Bak was assessed by immunohistochemical analysis. The terminal deoxytransferase-mediated deoxyuridine nick end-labeling assay was used to quantify apoptosis by flow cytometry. RESULTS: Tumor cells containing immunostaining for the antiapoptotic proteins Bcl-2 and Mcl-1 were present in 4 (15%) and 24 (92%) of the cases evaluated, respectively, whereas immunopositivity for the proapoptotic proteins Bax and Bak was found in 9 (35%) and 24 (92%) of the samples. Immunoreactivity to p53 was detected in 20 (77%) of the samples. There was a positive correlation between the expression of Bcl-2 and Bax and between Mcl-1 and Bak. A low fraction of apoptotic cells (<2.5%) in the pretreatment tumor samples was significantly correlated with increased 2-year survival in these patients. CONCLUSIONS: Our results establish the frequent expression of the Bcl-2 family proteins Bcl-2, Mcl-1, Bax, and Bak in locally advanced head and neck cancer. In addition, this study suggests that the apoptotic fraction in pretreatment tumor samples might be of prognostic importance for the outcome in these patients.


Subject(s)
Apoptosis , Carcinoma, Squamous Cell/genetics , Gene Expression , Head and Neck Neoplasms/genetics , Proto-Oncogene Proteins c-bcl-2/metabolism , Tumor Suppressor Protein p53/metabolism , Adult , Aged , Female , Humans , Immunohistochemistry , Laryngeal Neoplasms/genetics , Male , Middle Aged , Pharyngeal Neoplasms/genetics , Prognosis
19.
Br J Cancer ; 79(5-6): 952-8, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10070896

ABSTRACT

Proteins of the Bcl-2 family as well as p53 are important regulators of apoptosis. Alterations in the expression of these proteins can contribute to the formation of cancer, as well as influence tumour response to chemo- and radiotherapy. We used antibodies specific for the human Bcl-2, Mcl-1, Bax, Bak and p53 proteins to examine the expression of these apoptosis-regulating genes in 49 archival specimens of patients with radically resected non-small-cell lung cancer (NSCLC). Tumour cells containing immunostaining for the antiapoptotic proteins Bcl-2 and Mcl-1 were present in 31% and 58% of the cases evaluated, respectively, whereas immunopositivity for the proapoptotic proteins Bax and Bak was found in 47% and 58% of the samples. p53 immunopositivity was detected in 61% of the samples. The expression of Bcl-2 and p53 and the expression of Mcl-1 and Bax showed a positive association (P = 0.02 and P = 0.06 respectively), whereas the expression of Bax was inversely related to p53 (P = 0.008). The expression of Bcl-2 had a negative influence on relapse-free survival in this population of primary resected NSCLC patients (P = 0.02). The expression of p53 and Bcl-2 was significantly associated with metastasis-free survival (P < 0.01). Only patients with p53-positive tumours developed metastases during the follow-up period. Our results establish the frequent expression of the Bcl-2 family proteins Bcl-2, Mcl-1, Bax and Bak in NSCLC. It can be expected that Bcl-2 family members have no straightforward impact on clinical outcome in this disease because their interactions in the regulation of apoptosis are complex.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/surgery , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Proto-Oncogene Proteins c-bcl-2/analysis , Tumor Suppressor Protein p53/analysis , Apoptosis , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/mortality , Disease-Free Survival , Female , Humans , Immunohistochemistry , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Male , Membrane Proteins/analysis , Myeloid Cell Leukemia Sequence 1 Protein , Neoplasm Proteins/analysis , Neoplasm Staging , Proto-Oncogene Proteins/analysis , Retrospective Studies , Survival Rate , bcl-2 Homologous Antagonist-Killer Protein , bcl-2-Associated X Protein
20.
Laryngoscope ; 109(1): 65-9, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9917043

ABSTRACT

OBJECTIVE: This study examined the effects of old and new inactivation (sterilization) techniques on the radiologic and mechanical properties of ossicle homografts. MATERIALS AND METHODS: Ninety normal incuses and malleuses received either treatment with 1) 5% formaldehyde/cialit, 2) 1N NaOH, 3) 0.9% LpH, or 4) autoclaving at 134'C, or no treatment. All ossicles were assessed radiologically by high-resolution computed tomography. After imaging, all ossicles underwent mechanical testing by destructive axial compression in a mechanical testing machine measuring force and displacement. RESULTS: Ossicles treated with cialit, NaOH, or autoclaving showed a significant decrease of ultimate force and stiffness compared with controls. LpH treatment caused no such changes in these structural properties. Material properties of yield strength, ultimate strength, and elastic modulus were also altered by cialit, NaOH, and autoclaving, but were much more difficult to assess because of uncertainty in parameter estimates. There was a significant increase in radiologic density in autoclaved ossicles, a reduction in cialit- and LpH-treated ossicles, and no change in NaOH-treated ossicles. CONCLUSIONS: All tested inactivation procedures changed the biomechanical and/or radiologic properties of ossicle homografts. However, the new procedures used to inactivate infectious agents produced changes similar to the older treatments with formaldehyde/cialit. Human allografts are able to withstand harsh but safe sterilization procedures. The NaOH treatment seems to be the most suitable method for the future. The biologic (osteogenic) potentials of ossicle homografts treated with these new preservation/inactivation methods are still unknown. Further investigations are necessary to re-evaluate the clinical use of ossicle homografts in middle ear reconstructive surgery.


Subject(s)
Ear Ossicles/transplantation , Sterilization , Tissue Preservation , Adult , Aged , Aged, 80 and over , Ear Ossicles/ultrastructure , Humans , Microscopy, Electron, Scanning , Middle Aged , Transplantation, Homologous
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