24 resultados para PHARYNGEAL ECTODERM
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
BACKGROUND: Early exposure of infants and long-term immunity suggest that colonization with Moraxella catarrhalis is more frequent than is determined by routine culture. We characterized a reservoir of M. catarrhalis in pharyngeal lymphoid tissue. METHODS: Tissue from 40 patients (median age, 7.1 years) undergoing elective tonsillectomy and/or adenoidectomy was analyzed for the presence of M. catarrhalis by culture, real-time DNA and RNA polymerase chain reaction (PCR), immunohistochemical analysis (IHC), and fluorescent in situ hybridization (FISH). Histologic sections were double stained for M. catarrhalis and immune cell markers, to characterize the tissue distribution of the organism. Intracellular bacteria were identified using confocal laser scanning microscopy (CLSM). RESULTS: Twenty-nine (91%) of 32 adenoids and 17 (85%) of 20 tonsils were colonized with M. catarrhalis. Detection rates for culture, DNA PCR, RNA PCR, IHC, and FISH were 7 (13%) of 52, 10 (19%) of 52, 21 (41%) of 51, 30 (61%) of 49, and 42 (88%) of 48, respectively (P<.001). Histologic analysis identified M. catarrhalis in crypts, intraepithelially, subepithelially, and (using CLSM) intracellularly. M. catarrhalis colocalized with macrophages and B cells in lymphoid follicles. CONCLUSIONS: Colonization by M. catarrhalis is more frequent than is determined by surface culture, because the organism resides both within and beneath the epithelium and invades host cells.
Resumo:
An 11-year-old Warmblood gelding was presented for inspiratory stridor and dysphagia. Based on history and clinical examination, a solitary mass localised in the oropharynx was suspected. Due to its inaccessibility and defensive behaviour of the horse, it was difficult to visualise this mass either by upper airway endoscopy or by oral examination and the conventional imaging methods (radiology and ultrasound) provided only limited information. Fine needle aspiration cytology was suggestive of lymphoma, but the exact localisation and the extent of tissue infiltration of the tumour could only be defined by magnetic resonance imaging (MRI). MRI has proved to be a very useful diagnostic tool in equine lameness investigation and, as this case illustrates, it has considerable diagnostic potential for soft tissue examination of the equine head.
Resumo:
Evolutionary innovations, traits that give species access to previously unoccupied niches, may promote speciation and adaptive radiation. Here, we show that such innovations can also result in competitive inferiority and extinction. We present evidence that the modified pharyngeal jaws of cichlid fishes and several marine fish lineages, a classic example of evolutionary innovation, are not universally beneficial. A large-scale analysis of dietary evolution across marine fish lineages reveals that the innovation compromises access to energy-rich predator niches. We show that this competitive inferiority shaped the adaptive radiation of cichlids in Lake Tanganyika and played a pivotal and previously unrecognized role in the mass extinction of cichlid fishes in Lake Victoria after Nile perch invasion.
Resumo:
Objectives Pharyngeal arches develop in the head and neck regions, and give rise to teeth, oral jaws, the hyoid bone, operculum, gills, and pharyngeal jaws in teleosts. In this study, the expression patterns of genes in the sonic hedgehog (shh), wnt, ectodysplasin A (eda), and bone morphogenetic protein (bmp) pathways were investigated in the pharyngeal arches of Haplochromis piceatus, one of the Lake Victoria cichlids. Furthermore, the role of the shh pathway in pharyngeal arch development in H. piceatus larvae was investigated. Methods The expression patterns of lymphocyte enhancer binding factor 1 (lef1), ectodysplasin A receptor (edar), shh, patched 1 (ptch1), bmp4, sp5 transcription factor (sp5), sclerostin domain containing 1a (sostdc1a), and dickkopf 1 (dkk1) were investigated in H. piceatus larvae by in situ hybridization. The role of the shh pathway was investigated through morphological phenotypic characterization after its inhibition. Results We found that lef1, edar, shh, ptch1, bmp4, dkk1, sostdc1a, and sp5 were expressed not only in the teeth, but also in the operculum and gill filaments of H piceatus larvae. After blocking the shh pathway using cyclopamine, we observed ectopic shh expression and the disappearance of ptch1 expression. After six weeks of cyclopamine treatment, an absence of teeth in the oral upper jaws and a poor outgrowth of premaxilla, operculum, and gill filaments in juvenile H. piceatus were observed. Conclusions These results suggest that the shh pathway is important for the development of pharyngeal arch derivatives such as teeth, premaxilla, operculum, and gill filaments in H. piceatus.
Resumo:
Clinical-forensic examination of strangulation victims is an increasing part of the routine of many forensic pathology institutes. The cases examined between 2004 and 2008 at the Institute of Legal Medicine of the Hanover Medical School were retrospectively analysed. In total, the study material comprised 218 victims (175 females and 43 males). In 80.7 %, the clinical-forensic examination was performed within 24 hours after the incident. In the overwhelming number of cases, the alleged perpetrator was no stranger. 128 victims (58.7 %) had strangulation marks, 32 victims (14.7 %) ligature marks and 65 victims (29.8 %) nail marks. Four victims showed injuries of the laryngeal and pharyngeal structures (reddening, hematomas, swelling and in one case a fracture of the cricoid cartilage on both sides). Extensive petechiae were predominantly seen in the conjunctivae, the buccal mucosa and the skin of the face in cases where the victims suffered a loss of consciousness. 87 cases (39.9% were classified as potentially life-threatening and 30 cases (13.8 %) as acute life-threatening events. This classification is of legal relevance for the penalty. In addition, 60 victims experienced sexual violence. These results suggest that early clinical-forensic examination is crucial for documenting forensic evidence in support of police investigations and may deliver significant details relevant in court.
Differential effects of long and short carbon nanotubes on the gas-exchange region of the mouse lung
Resumo:
Abstract We hypothesise that inflammatory response and morphological characteristics of lung parenchyma differ after exposure to short or long multi-walled carbon nanotubes (MWCNT). Mice were subjected to a single dose of vehicle, short or long MWCNT by pharyngeal aspiration. Bronchoalveolar lavage fluid (BALF) obtained at 24 h was analysed for inflammatory reaction and lung tissue was analysed for morphological alterations using stereology. Short MWCNT had stronger potential to induce polymorphonuclear cells whereas long MWCNT increased interleukin-6 levels in BALF. Alveolar septal fibrosis was only observed with short MWCNT. Type II pneumocyte hypertrophy was only detected with long MWCNT. There was no reduction in total alveolar surface area and no sign of type II cell hyperplasia. We observed mild inflammatory and pathological responses to short and long MWCNT in the lung parenchyma depending on the size of the applied MWCNT.
Resumo:
Background Moraxella catarrhalis, a major nasopharyngeal pathogen of the human respiratory tract, is exposed to rapid downshifts of environmental temperature when humans breathe cold air. It was previously shown that the prevalence of pharyngeal colonization and respiratory tract infections caused by M. catarrhalis are greatest in winter. The aim of this study was to investigate how M. catarrhalis uses the physiologic exposure to cold air to upregulate pivotal survival systems in the pharynx that may contribute to M. catarrhalis virulence. Results A 26°C cold shock induces the expression of genes involved in transferrin and lactoferrin acquisition, and enhances binding of these proteins on the surface of M. catarrhalis. Exposure of M. catarrhalis to 26°C upregulates the expression of UspA2, a major outer membrane protein involved in serum resistance, leading to improved binding of vitronectin which neutralizes the lethal effect of human complement. In contrast, cold shock decreases the expression of Hemagglutinin, a major adhesin, which mediates B cell response, and reduces immunoglobulin D-binding on the surface of M. catarrhalis. Conclusion Cold shock of M. catarrhalis induces the expression of genes involved in iron acquisition, serum resistance and immune evasion. Thus, cold shock at a physiologically relevant temperature of 26°C induces in M. catarrhalis a complex of adaptive mechanisms that enables the bacterium to target their host cellular receptors or soluble effectors and may contribute to enhanced growth, colonization and virulence.
Resumo:
The antiinflammatory agent curcumin (diferuloylmethane) has a potential to mitigate cancer therapy-induced mucositis. We assessed the in vitro extent of its bactericidal activity and determined the kinetics of its antiinflammatory effect on pharyngeal cells. Bactericidal activity was assessed using the LIVE/DEAD® Kit after 4 h of exposure to curcumin (50-200 μM) in 18 oropharyngeal species commonly associated with bacteremia in febrile neutropenia. Moraxella catarrhalis or its outer membrane vesicles were used to determine the inhibitory effect of curcumin on bacteria-induced proinflammatory activity as determined by cytokine release into the supernatant of Detroit 562 pharyngeal cells using the Luminex® xMAP® technology. Curcumin exerted a concentration-dependent bactericidal effect on all 18 species tested. After 4 h at 200 μM, 12 species tested were completely killed. Preincubation of Detroit cells with 200 μM curcumin for 5 to 60 min resulted in complete suppression of the release of tumor necrosis factor-α, interleukin (IL)-6, IL-8, monocyte chemoattractant protein 1, granulocyte macrophage-colony stimulating factor, and vascular endothelial growth factor. Fibroblast growth factor-2 and interferon-γ were not affected. Repetitive exposure to curcumin resulted in repetitive suppression of cytokine/chemokine expression lasting from 4 to 6 h. Through reduction of oral microbial density as well as suppression of inflammation cascades curcumin may prevent cancer therapy-induced oral mucositis, e.g., when applied as multiple daily mouth washes.
Resumo:
A modified uvulopalatopharyngoplasty (UPPP) was carried out between January 1992 and December 2003 at the ENT Department of the Inselspital in Bern in 146 patients with habitual or complicated rhonchopathy. The operation consisted of a classical tonsillectomy or residual tonsil resection and additional shortening of the uvula. The natural mucosal fold between the uvula and the upper pole of the tonsils was carefully preserved. A wide opening to the rhinopharynx was created by asymmetric suturing of the glossopalantine and pharyngopalatine arches. A retrospective questionnaire with regard to rhonchopathy, phases of apnea, daytime drowsiness, obstruction of nasal breathing, long-term complications and patient satisfaction was used to evaluate the short-term and long-term effectiveness of the modified UPPP as well as the incidence of adverse side effects. Complete postoperative courses were evaluated in 116 patients. Surgical complications were restricted to one case with postoperative hemorrhage. A velum insufficiency or postoperative rhinopharyngeal stenosis did not occur. Eighty-three patients (72%) confirmed a persistent suppression or substantial improvement of the rhonchopathy. Disappearance or decrease of sleep apnea was confirmed in 12 (63%) out of 19 postoperative polysomnographic follow-up investigations. Long-term complications occurred in a total of 27 (23%) of 116 patients. They were confined to minor problems such as dryness of the mouth (n = 12), slight difficulty in swallowing (n = 7), discrete speech disturbances (n = 1), and slight pharyngeal dysesthesias (n = 7) with feeling of a lump in the throat and compulsive clearing of the throat. Eighty-five patients (73%) reported that they were satisfied with the postoperative result even several years after the operation. Looking back, 31 patients (27%) would no longer have the operation performed. The inadequate result of the rhonchopathy was specified as the reason by 21 patients. Ten patients had unpleasant memories of the operation because of intensive postoperative pain. Snoring and apneic phases are suppressed or improved by non-traumatic UPPP in the majority of patients. This effect persisted even years after the operation.
Resumo:
Reconstruction of the anterior skull base and fronto-orbital framework following extensive tumor resection is both challenging and controversial. Dural defects are covered with multiple sheets of fascia lata that provide sufficient support and avoid herniation. Plating along the skull base is contraindicated. After resection of orbital walls, grafting is necessary if the periosteum or parts of the periorbital tissue had to be removed, to avoid enophthalmus or strabism. Free bone grafts exposed to the sinonasal or pharyngeal cavity are vulnerable to infection or necrosis: therefore, covering the grafts with vascularized tissue, such as the Bichat fat-pad or pedicled temporalis flaps, should reduce these complications. Alloplastic materials are indispensable in cranial defects, whereas microsurgical free tissue transfer is indicated in cases of orbital exenteration and skin defects. The authors review their experience and follow-up of 122 skull base reconstructions following extensive subcranial tumor resection. Most significant complications were pneumocranium in 4.9%, CSF leaks in 3.2%, and partial bone resorption in 8.1%.
Resumo:
BACKGROUND: Gastroesophageal reflux is implicated in the pathogenesis of asthma and chronic cough. To date most studies have focused on acid reflux measured by pH below the upper esophageal sphincter (UES). The aim of this study was to assess the relationship between cough and reflux through the UES into the pharynx. METHODS: Thirty-seven patients with asthma (19) and chronic cough (18) were recruited from the respiratory clinic. Reflux was monitored using a combined multichannel intraluminal impedance and pH probe by detecting (1) bolus reflux episodes within the esophagus and in the pharynx and (2) acidic reflux episodes within the esophagus and in the pharynx. All acid suppressive therapy was stopped for at least 7 days before the study. Demonstration of cough being linked to reflux was achieved using the symptom association probability (SAP). This was calculated using a 2-minute association window between symptoms and bolus entry into the esophagus. SAP was considered positive if >95%. RESULTS: A positive SAP for cough was noted in 7/26 patients reporting symptoms on the day of monitoring. Compared with SAP-negative patients, SAP-positive patients had both a greater number [median (interquartile range), 5(2 to 8) vs. 2(0 to 4), P<0.05] and a higher proportion of reflux episodes crossing the UES into the pharynx [25%(14% to 28%) vs. 7% (2% to 14%), P<0.02]. There was no difference in the number of reflux episodes or acid exposure time in the distal esophagus between SAP-positive and SAP-negative patients. Only 1% to 2% of episodes were detected by the pharyngeal pH sensor. CONCLUSIONS: Impedance detected pharyngeal reflux episodes are important factors in symptom production in cough patients.
Resumo:
BACKGROUND: Endoderm organ primordia become specified between gastrulation and gut tube folding in Amniotes. Although the requirement for RA signaling for the development of a few individual endoderm organs has been established a systematic assessment of its activity along the entire antero-posterior axis has not been performed in this germ layer. METHODOLOGY/PRINCIPAL FINDINGS: RA is synthesized from gastrulation to somitogenesis in the mesoderm that is close to the developing gut tube. In the branchial arch region specific levels of RA signaling control organ boundaries. The most anterior endoderm forming the thyroid gland is specified in the absence of RA signaling. Increasing RA in anterior branchial arches results in thyroid primordium repression and the induction of more posterior markers such as branchial arch Hox genes. Conversely reducing RA signaling shifts Hox genes posteriorly in endoderm. These results imply that RA acts as a caudalizing factor in a graded manner in pharyngeal endoderm. Posterior foregut and midgut organ primordia also require RA, but exposing endoderm to additional RA is not sufficient to expand these primordia anteriorly. We show that in chick, in contrast to non-Amniotes, RA signaling is not only necessary during gastrulation, but also throughout gut tube folding during somitogenesis. Our results show that the induction of CdxA, a midgut marker, and pancreas induction require direct RA signaling in endoderm. Moreover, communication between CdxA(+) cells is necessary to maintain CdxA expression, therefore synchronizing the cells of the midgut primordium. We further show that the RA pathway acts synergistically with FGF4 in endoderm patterning rather than mediating FGF4 activity. CONCLUSIONS/SIGNIFICANCE: Our work establishes that retinoic acid (RA) signaling coordinates the position of different endoderm organs along the antero-posterior axis in chick embryos and could serve as a basis for the differentiation of specific endodermal organs from ES cells.
Resumo:
Moraxella catarrhalis, a major nasopharyngeal pathogen of the human respiratory tract, is exposed to rapid and prolonged downshifts of environmental temperature when humans breathe cold air. In the present study, we show that a 26 degrees C cold shock up-regulates the expression of UspA1, a major adhesin and putative virulence factor of M. catarrhalis, by prolonging messenger RNA half-life. Cold shock promotes M. catarrhalis adherence to upper respiratory tract cells via enhanced binding to fibronectin, an extracellular matrix component that mediates bacterial attachment. Exposure of M. catarrhalis to 26 degrees C increases the outer membrane protein-mediated release of the proinflammatory cytokine interleukin 8 in pharyngeal epithelial cells. Furthermore, cold shock at 26 degrees C enhances the binding of salivary immunoglobulin A on the surface of M. catarrhalis. These data indicate that cold shock at a physiologically relevant temperature of 26 degrees C affects the nasopharyngeal host-pathogen interaction and may contribute to M. catarrhalis virulence.
Resumo:
The objective of this study was to examine the association of pharyngeal lymphoid hyperplasia (PLH), recurrent laryngeal neuropathy (RLN), mucus accumulation (MA) score and tracheobronchial secretion neutrophil percentage (TBS-N) with rider-assessed performance in sport horses. Airway endoscopy scores, tracheobronchial secretion cytology, rider-assessed general impression and willingness to perform were investigated in 171 top-level sport horses. Increased MA appears to be associated with poor willingness to perform in sport horses. Older horses had decreased PLH scores and increased TBS-N. Mucus accumulation scores > or =3 were associated with increased odds (mean 9.92; upper and lower 95% confidence intervals: 1.5-64.6) of poor rather than excellent willingness to perform. A TBS-N of 20-50% compared with <20% was associated with decreased odds (median 0.11; upper and lower 95% CI: 0.02-0.66) of poor rather than excellent willingness to perform. In addition, horses with an RLN grade > or =2 had significantly higher odds for giving a poorer general impression and willingness to perform. This finding, however, must be interpreted with caution, since only two horses had significant RLN (grade > or =3).
Resumo:
The purpose of the present study was to describe normal magnetic resonance (MR) imaging anatomy of the equine larynx and pharynx and to present the optimal protocol, sequences, and possible limitations of this examination technique. Using a 0.3 T unit, the laryngeal and pharyngeal regions was imaged in two horses. The protocol consisted of sagittal and transverse T2-weighted (T2w) fast spin echo, transverse T1-weighted (T1w) spin echo, and dorsal high-resolution T1w gradient echo (both pre- and postcontrast enhancement) sequences. Euthanasia was performed at the end of the imaging procedure. Macroscopic anatomy of the cadaver sections were compared with the MR images in transverse, midsagittal, and parasagittal planes. There was good differentiation of anatomic structures, including soft tissues. The laryngeal cartilages, hyoid apparatus, and upper airway muscle groups with their attachments could be clearly identified. However, it was not always possible to delineate individual muscles in each plane. Most useful were both T2w and T1w transverse sequences. Intravenous application of contrast medium was helpful to identify blood vessels. The MR images corresponded with the macroscopic anatomy of cadaver sections.