Macroscopic Quantum Tunneling of a Bose Condensate

We study, by means of a variational method, the stability of a condensate in a magnetically trapped atomic Bose gas with a negative scattering length and find that the condensate is unstable in general. However, for temperatures sufficiently close to the critical temperature the condensate turns out to be metastable. For that case we determine in the usual WKB approximation the decay rate of the condensate due to macroscopic quantum fluctuations. When appropriate, we also calculate the decay rate due to thermal fluctuations. An important feature of our approach is that (nonsingular) phase fluctuations of the condensate are taken into account exactly.Comment: Invited paper for the Journal of Statistical Physic

Clinical Diagnostic Accuracy of Otitis Media with Effusion in Children, and Significance of Myringotomy: Diagnostic or Therapeutic?

The specific aims of this prospective survey were to determine the accuracy of traditional diagnostic tools, such as pneumatic otoscopy, otomicroscopy, and tympanometry, and evaluate the usefulness of myringotomy as a diagnostic method; also to determine the significance of myringotomy in treating otitis media with effusion (OME). The status of middle ear of 51 children (85 ears) from November 2002 to February 2003 was examined using pneumatic otoscopy, otomicroscopy, and tympanometry, and the presence/absence of middle ear effusion was confirmed by myringotomy. The otomicroscopy was the most sensitive and specific one among three diagnostic tools. But, it had some false positive cases. This study failed to show the therapeutic efficacy of myringotomy. Otomicroscopy seems to have the potential to become the standard for diagnosis of OME and for validation of pneumatic otoscopy in children. However, when otoscopic, otomicroscopic findings and tympanogram of suspected ear show poor correlation, myringotomy can be used to confirm the presence of OME, as the diagnostic modality. As the therapeutic modality, we think that it is proper to limit indications of myringotomy to some selected cases

Management for the Children with Otitis Media with Effusion in the Tertiary Hospital

ObjectivesRecently, new evidence-based recommendations have been introduced for diagnosing and managing otitis media with effusion (OME) in children. However, there are some difficulties to follow the general guidelines in the tertiary hospitals. The purpose is to evaluate the efficiency of antibiotics or antihistamines for treatment of children with OME in the tertiary hospital with a randomized prospective clinical study.MethodsEighty-four children with OME who had been diagnosed in the tertiary hospital were randomized to receive 5 different medications for 2 weeks. We prescribed antibiotics (amoxicillin-clavulanate syrup) in Group I (n=16), antibiotics/steroids (prednisolone) in Group II (n=18), antibiotics/antihistamines (ebastine) in Group III (n=15), antibiotics/steroids/antihistamines in Group IV (n=17), and mucolytics (ivy leaf extract) in Group V (n=17) for control. We followed-up children every 2 weeks and evaluated the state of OME at 3 months.ResultsThirty six (42.9%) of 84 children were resolved within average 6.9 weeks after the treatments. Thirty-six (42.9%) were treated with ventilation tube insertion and 12 patients (14.3%) were observed. There was no difference in the resolution rates of OME among the five different protocols (P>0.05). There was no difference in the resolution rates among groups who used steroids, antihistamines, steroids and antihistamines, or other medications to manage 42 children with allergies (P>0.05).ConclusionIn the tertiary hospital, the cure rate of children with OME was not as high as well-known, and antibiotics or anti-allergic medications were not more effective than control. We may, therefore, need any other guidelines which are different from the previous evidence-based recommendations, including early operation in the tertiary hospitals

Endoscopic procedures for removal of foreign bodies of the aerodigestive tract: The Bugando Medical Centre experience

<p>Abstract</p> <p>Background</p> <p>Foreign bodies in the aerodigestive tract continue to be a common problem that contributes significantly to high morbidity and mortality worldwide. This study was conducted to describe our own experience with endoscopic procedures for removal of foreign bodies in the aerodigestive tract, in our local setting and compare with what is described in literature.</p> <p>Methods</p> <p>This was a prospective descriptive study which was conducted at Bugando Medical Centre between January 2008 and December 2009. Data were collected using a structured questionnaire and analyzed using SPSS computer software version 15.</p> <p>Results</p> <p>A total of 98 patients were studied. Males outnumbered females by a ratio of 1.1:1. Patients aged 2 years and below were the majority (75.9%). The commonest type of foreign bodies in airways was groundnuts (72.7%) and in esophagus was coins (72.7%). The trachea (52.2%) was the most common site of foreign body's lodgment in the airways, whereas cricopharyngeal sphincter (68.5%) was the commonest site in the esophagus. Rigid endoscopy with forceps removal under general anesthesia was the main treatment modality performed in 87.8% of patients. The foreign bodies were successfully removed without complications in 90.8% of cases. Complication rate was 7.1% and bronchopneumonia was the most common complication accounting for 42.8% of cases. The mean duration of hospital stay was 3.4 days and mortality rate was 4.1%.</p> <p>Conclusion</p> <p>Aerodigestive tract foreign bodies continue to be a significant cause of childhood morbidity and mortality in our setting. Rigid endoscopic procedures under general anesthesia are the main treatment modalities performed. Prevention is highly recommended whereby parents should be educated to keep a close eye on their children and keep objects which can be foreign bodies away from children's reach.</p

Lysozyme M deficiency leads to an increased susceptibility to Streptococcus pneumoniae-induced otitis media

<p>Abstract</p> <p>Background</p> <p>Lysozyme is an antimicrobial innate immune molecule degrading peptidoglycan of the bacterial cell wall. Lysozyme shows the ubiquitous expression in wide varieties of species and tissues including the tubotympanum of mammals. We aim to investigate the effects of lysozyme depletion on pneumococcal clearance from the middle ear cavity.</p> <p>Methods</p> <p>Immunohistochemistry was performed to localize lysozyme in the Eustachian tube. Lysozyme expression was compared between the wild type and the lysozyme M^-/-mice using real time quantitative RT-PCR and western blotting. Muramidase activity and bactericidal activity of lysozyme was measured using a lysoplate radial diffusion assay and a liquid broth assay, respectively. To determine if depletion of lysozyme M increases a susceptibility to pneumococal otitis media, 50 CFU of <it>S. pneumoniae </it>6B were transtympanically inoculated to the middle ear and viable bacteria were counted at day 3 and 7 with clinical grading of middle ear inflammation.</p> <p>Results</p> <p>Immunolabeling revealed that localization of lysozyme M and lysozyme P is specific to some/particular cell types of the Eustachian tube. Lysozyme P of lysozyme M^-/-mice was mainly expressed in the submucosal gland but not in the tubal epithelium. Although lysozyme M^-/-mice showed compensatory up-regulation of lysozyme P, lysozyme M depletion resulted in a decrease in both muramidase and antimicrobial activities. Deficiency in lysozyme M led to an increased susceptibility to middle ear infection with <it>S. pneumoniae </it>6B and resulted in severe middle ear inflammation, compared to wild type mice.</p> <p>Conclusion</p> <p>The results suggest that lysozyme M plays an important role in protecting the middle ear from invading pathogens, particularly in the early phase. We suggest a possibility of the exogenous lysozyme as an adjuvant therapeutic agent for otitis media, but further studies are necessary.</p

Sh3pxd2b Mice Are a Model for Craniofacial Dysmorphology and Otitis Media

Craniofacial defects that occur through gene mutation during development increase vulnerability to eustachian tube dysfunction. These defects can lead to an increased incidence of otitis media. We examined the effects of a mutation in the Sh3pxd2b gene (Sh3pxd2bnee) on the progression of otitis media and hearing impairment at various developmental stages. We found that all mice that had the Sh3pxd2bnee mutation went on to develop craniofacial dysmorphologies and subsequently otitis media, by as early as 11 days of age. We found noteworthy changes in cilia and goblet cells of the middle ear mucosa in Sh3pxd2bnee mutant mice using scanning electronic microscopy. By measuring craniofacial dimensions, we determined for the first time in an animal model that this mouse has altered eustachian tube morphology consistent with a more horizontal position of the eustachian tube. All mutants were found to have hearing impairment. Expression of TNF-α and TLR2, which correlates with inflammation in otitis media, was up-regulated in the ears of mutant mice when examined by immunohistochemistry and semi-quantitative RT-PCR. The mouse model with a mutation in the Sh3pxd2b gene (Sh3pxd2bnee) mirrors craniofacial dysmorphology and otitis media in humans

Lancet Microbe

BACKGROUND: There has been a global pursuit to improve the diagnosis of tuberculosis in young children by applying diagnostic methods on accessible biospecimens such as stool. We aimed to conduct a systematic review on the accuracy of stool-based molecular tests for tuberculosis diagnosis in children and to assess the impact of the available pre-processing methods and other design characteristics. METHODS: In this systematic review and meta-analysis, we evaluated studies in children younger than 16 years with presumptive tuberculosis that were published in English, Spanish, French, and Portuguese from Jan 1, 2000, to May 3, 2024, in MEDLINE, Embase, and Embase Classic, comparing the molecular detection of Mycobacterium tuberculosis DNA in stool with microbiological tests on other samples or a clinical diagnosis. We did not exclude studies based on geographical location, sample size, or study design if they were reporting primary data. Two independent reviewers (LC-C and SM) screened titles, abstracts, and full-text articles for eligibility and extracted data on study characteristics, study population, and diagnostic performance. If information relevant to the main analysis was not reported in the article, the corresponding authors were contacted. Point estimates and 95% CIs were calculated for sensitivity and specificity for each study and for the different molecular tests (Xpert MTB/RIF, Xpert Ultra MTB/RIF [Cepheid, Sunnyvale, CA, USA], and other tests) versus a reference standard (culture only, any bacteriological confirmation, and tuberculosis case definition). Sensitivity and specificity were stratified by the stool processing method. We also quantified the additionality of stool Xpert Ultra tests for tuberculosis bacteriological confirmation. The protocol was registered with PROSPERO, CRD42022341514. FINDINGS: A total of 4521 records were identified through the database search, one record was identified from an article bibliography, and 67 studies were retained for full-text reading. 39 studies were included in the qualitative synthesis, 35 of which were included in the meta-analyses. When using any bacteriological confirmation from a respiratory sample as the reference standard, stool Xpert sensitivity was 0·60 (95% CI 0·48-0·71), stool Xpert Ultra sensitivity was 0·73 (0·63-0·81), and sensitivity was 0·44 (0·29-0·60) for other in-house molecular methods combined. When using tuberculosis case definition as the reference standard, stool Xpert sensitivity was 0·23 (0·11-0·41), stool Xpert Ultra sensitivity was 0·38 (0·22-0·56), and sensitivity was 0·17 (0·09-0·23) for other in-house molecular methods. The addition of stool Xpert Ultra increased bacteriological confirmation of tuberculosis by 38·6% overall. Further, the utilisation of centrifuge-free simplified methods improved the sensitivity of stool Xpert Ultra when using any bacteriological confirmation as a reference standard (0·77 [0·66-0·85] for centrifuge-free methods vs 0·61 [0·41-0·78] for non-centrifuge-free methods). INTERPRETATION: This systematic review and meta-analysis supports the use of Xpert Ultra in stool samples as a diagnostic tool for paediatric tuberculosis diagnosis. Stool-based Xpert Ultra can contribute to increase the bacteriological confirmation in this population, even when respiratory specimens are also tested. FUNDING: The EDCTP2 programme supported by the EU via Stool4TB Project and the European Society of Pediatric Infectious Diseases