48 research outputs found
Subcutaneous emphysema in a case of infective sinusitis: a case report
<p>Abstract</p> <p>Introduction</p> <p>Subcutaneous emphysema with pneumomediastinum is a rare phenomenon with a high morbidity and may occur spontaneously.</p> <p>Case presentation</p> <p>A 30-year-old Caucasian man presented with sudden onset of a painful, swollen neck and was found, via clinical and radiological examination to have subcutaneous emphysema. A swallow study showed no oesophageal perforation. Computed tomography of his neck and thorax demonstrated pneumomediastinum but no other pathology. Management was conservative with intravenous antibiotics, fluids and no oral intake. He had a history of a productive cough and a flexible nasoendoscopy found purulent sinusitis which was treated with topical nasal washes. The patient was discharged after 72 hours and will be followed up by the otolaryngology-head and neck service.</p> <p>Conclusions</p> <p>Infective sinusitis is a rare cause of subcutaneous emphysema and pneumomediastinum. It may be managed conservatively provided there is early recognition and exclusion of more serious pathology, such as a ruptured trachea or oesophagus.</p
Clinicopathological characteristics of resected adenosquamous cell carcinoma of the lung: Risk of coexistent double cancer
<p>Abstract</p> <p>Background</p> <p>adenosquamous carcinoma (ADSQ) of non-small cell lung cancer (NSCLC) is a rare disease and the biological behavior and clinicopathological characteristics have not yet been thoroughly described.</p> <p>Method</p> <p>This study reviewed the patient charts of 11 (1.6%) ADSQ cases among 779 patients with primary lung cancer who underwent a lung resection. The characteristics and clinicopathological factors were evaluated retrospectively.</p> <p>Results</p> <p>Six of the 11 patients with ADSQ were male and five were female. The mean age was 67.3 years' olds. Three patients had pathological stage IA, one patient each had stage IB and IIA, five patients had stage IIIA, and one patient stage IIIB. Five patients had coexistent double cancer including 2 gastric, 1 rectal, 1 prostate and 1 bladder cancer. ADSQ was found less frequently in males than squamous cell carcinoma (SQ). ADSQ was found more frequently in older patients, with advanced stage, advanced T status, and lymph node metastases than adenocarcinoma (AD). The proportion with coexistent double cancer of AD, SQ, and ADSQ were 21.1, 17.6, and 45.5%, respectively. ADSQ had a significantly correlation with double cancer (ADSQ vs. non- ADSQ p = 0.03). A multivariate analysis showed no significant prognostic difference between the patients with ADSQ and non- ADSQ.</p> <p>Conclusions</p> <p>In this study, cases with ADSQ showed no significantly prognostic difference in comparison to AD and SQ. However, surgeons must be cautious of any coexistent double cancer because approximately half of all patients with ADSQ of the lung have double cancer.</p
Protein Phosphatase 2A Controls Ethylene Biosynthesis by Differentially Regulating the Turnover of ACC Synthase Isoforms
The gaseous hormone ethylene is one of the master regulators of development and physiology throughout the plant life cycle. Ethylene biosynthesis is stringently regulated to permit maintenance of low levels during most phases of vegetative growth but to allow for rapid peaks of high production at developmental transitions and under stress conditions. In most tissues ethylene is a negative regulator of cell expansion, thus low basal levels of ethylene biosynthesis in dark-grown seedlings are critical for optimal cell expansion during early seedling development. The committed steps in ethylene biosynthesis are performed by the enzymes 1-aminocyclopropane 1-carboxylate synthase (ACS) and 1-aminocyclopropane 1-carboxylate oxidase (ACO). The abundance of different ACS enzymes is tightly regulated both by transcriptional control and by post-translational modifications and proteasome-mediated degradation. Here we show that specific ACS isozymes are targets for regulation by protein phosphatase 2A (PP2A) during Arabidopsis thaliana seedling growth and that reduced PP2A function causes increased ACS activity in the roots curl in 1-N-naphthylphthalamic acid 1 (rcn1) mutant. Genetic analysis reveals that ethylene overproduction in PP2A-deficient plants requires ACS2 and ACS6, genes that encode ACS proteins known to be stabilized by phosphorylation, and proteolytic turnover of the ACS6 protein is retarded when PP2A activity is reduced. We find that PP2A and ACS6 proteins associate in seedlings and that RCN1-containing PP2A complexes specifically dephosphorylate a C-terminal ACS6 phosphopeptide. These results suggest that PP2A-dependent destabilization requires RCN1-dependent dephosphorylation of the ACS6 C-terminus. Surprisingly, rcn1 plants exhibit decreased accumulation of the ACS5 protein, suggesting that a regulatory phosphorylation event leads to ACS5 destabilization. Our data provide new insight into the circuitry that ensures dynamic control of ethylene synthesis during plant development, showing that PP2A mediates a finely tuned regulation of overall ethylene production by differentially affecting the stability of specific classes of ACS enzymes
Dual-Level Regulation of ACC Synthase Activity by MPK3/MPK6 Cascade and Its Downstream WRKY Transcription Factor during Ethylene Induction in Arabidopsis
Plants under pathogen attack produce high levels of ethylene, which plays important roles in plant immunity. Previously, we reported the involvement of ACS2 and ACS6, two Type I ACS isoforms, in Botrytis cinerea–induced ethylene biosynthesis and their regulation at the protein stability level by MPK3 and MPK6, two Arabidopsis pathogen-responsive mitogen-activated protein kinases (MAPKs). The residual ethylene induction in the acs2/acs6 double mutant suggests the involvement of additional ACS isoforms. It is also known that a subset of ACS genes, including ACS6, is transcriptionally induced in plants under stress or pathogen attack. However, the importance of ACS gene activation and the regulatory mechanism(s) are not clear. In this report, we demonstrate using genetic analysis that ACS7 and ACS11, two Type III ACS isoforms, and ACS8, a Type II ACS isoform, also contribute to the B. cinerea–induced ethylene production. In addition to post-translational regulation, transcriptional activation of the ACS genes also plays a critical role in sustaining high levels of ethylene induction. Interestingly, MPK3 and MPK6 not only control the stability of ACS2 and ACS6 proteins via direct protein phosphorylation but also regulate the expression of ACS2 and ACS6 genes. WRKY33, another MPK3/MPK6 substrate, is involved in the MPK3/MPK6-induced ACS2/ACS6 gene expression based on genetic analyses. Furthermore, chromatin-immunoprecipitation assay reveals the direct binding of WRKY33 to the W-boxes in the promoters of ACS2 and ACS6 genes in vivo, suggesting that WRKY33 is directly involved in the activation of ACS2 and ACS6 expression downstream of MPK3/MPK6 cascade in response to pathogen invasion. Regulation of ACS activity by MPK3/MPK6 at both transcriptional and protein stability levels plays a key role in determining the kinetics and magnitude of ethylene induction