Selenium alleviates chromium stress and promotes chromium uptake in As-hyperaccumulator Pteris vittata: Cr reduction and cellar distribution.

Arsenic-hyperaccumulator Pteris vittata exhibits remarkable absorption ability for chromium (Cr) while beneficial element selenium (Se) helps to reduce Cr-induced stress in plants. However, the effects of Se on the Cr uptake and the associated mechanisms in P. vittata are unclear, which were investigated in this study. P. vittata plants were grown for 14 days in 0.2-strength Hoagland solution containing 10 (Cr10) or 100 µM (Cr100) chromate (CrVI) and 1 µM selenate (Se1). The plant biomass, malondialdehyde contents, total Cr and Se contents, Cr speciation, expression of genes associated with Cr uptake, and Cr subcellular distribution in P. vittata were determined. P. vittata effectively accumulated Cr by concentrating 96-99% in the roots under Cr100 treatment. Further, Se substantially increased its Cr contents by 98% to 11,596 mg kg-1 in the roots, which may result from Se's role in reducing its oxidative stress as supported by 27-62% reduction in the malondialdehyde contents. Though supplied with CrVI, up to 98% of the Cr in the roots was reduced to insoluble chromite (CrIII), with 83-89% being distributed on root cell walls. Neither Cr nor Se upregulated the expression of sulfate transporters PvSultr1;1-1;2 or phosphate transporter PvPht1;4, indicating their limited role in Cr uptake. P. vittata effectively accumulates Cr in the roots mainly as CrIII on cell walls and Se effectively enhances its Cr uptake by reducing its oxidative stress. Our study suggests that Se can be used to enhance P. vittata Cr uptake and reduce its oxidative stress, which may have application in phytostabilization of Cr-contaminated soils.

Foliar-selenium enhances plant growth and arsenic accumulation in As-hyperaccumulator Pteris vittata: Critical roles of GSH-GSSG cycle and arsenite antiporters PvACR3.

It is known that selenium (Se) enhances plant growth and arsenic (As) accumulation in As-hyperaccumulator Pteris vittata, but the associated mechanisms are unclear. In this study, P. vittata was exposed to 50 µM arsenate (AsV) under hydroponics plus 25 or 50 µM foliar selenate. After 3-weeks of growth, the plant biomass, As and Se contents, As speciation, malondialdehyde (MDA) and glutathione (GSH and GSSG) levels, and important genes related to As-metabolism in P. vittata were determined. Foliar-Se increased plant biomass by 17 - 30 %, possibly due to 9.1 - 19 % reduction in MDA content compared to the As control. Further, foliar-Se enhanced the As contents by 1.9-3.5 folds and increased arsenite (AsIII) contents by 64 - 136 % in the fronds. The increased AsV reduction to AsIII was attributed to 60 - 131 % increase in glutathione peroxidase activity, which mediates GSH oxidation to GSSG (8.8 -29 % increase) in the fronds. Further, foliar-Se increased the expression of AsIII antiporters PvACR3;1-3;3 by 1.6 - 2.1 folds but had no impact on phosphate transporters PvPht1 or arsenate reductases PvHAC1/2. Our results indicate that foliar-Se effectively enhances plant growth and arsenic accumulation by promoting the GSH-GSSG cycle and upregulating gene expression of AsIII antiporters, which are responsible for AsIII translocation from the roots to fronds and AsIII sequestration into the fronds. The data indicate that foliar-Se can effectively improve phytoremediation efficiency of P. vittata in As-contaminated soils.

Insoluble-Phytate Improves Plant Growth and Arsenic Accumulation in As-Hyperaccumulator Pteris vittata: Phytase Activity, Nutrient Uptake, and As-Metabolism.

Phytate, the principal P storage in plant seeds, is also an important organic P in soils, but it is unavailable for plant uptake. However, the As-hyperaccumulator Pteris vittata can effectively utilize soluble Na-phytate, while its ability to utilize insoluble Ca/Fe-phytate is unclear. Here, we investigated phytate uptake and the underlying mechanisms based on the phytase activity, nutrient uptake, and expression of genes involved in As metabolisms. P. vittata plants were cultivated hydroponically in 0.2-strength Hoagland nutrient solution containing 50 µM As and 0.2 mM Na/Ca/Fe-phytate, with 0.2 mM soluble-P as the control. As the sole P source, all three phytates supported P. vittata growth, with its biomass being 3.2-4.1 g plant-1 and Ca/Fe-phytate being 19-29% more effective than Na-phytate. Phytate supplied soluble P to P. vittata probably via phytase hydrolysis, which was supported by 0.4-0.7 nmol P min-1 g-1 root fresh weight day-1 phytase activity in its root exudates, with 29-545 µM phytate-P being released into the growth media. Besides, compared to Na-phytate, Ca/Fe-phytate enhanced the As contents by 102-140% to 657-781 mg kg-1 in P. vittata roots and by 43-86% to 1109-1447 mg kg-1 in the fronds, which was accompanied by 21-108% increase in Ca and Fe uptake. The increased plant As is probably attributed to 1.3-2.6 fold upregulation of P transporters PvPht1;3/4 for root As uptake, and 1.8-4.3 fold upregulation of arsenite antiporters PvACR3/3;1/3;3 for As translocation to and As sequestration into the fronds. This is the first report to show that, besides soluble Na-phytate, P. vittata can also effectively utilize insoluble Ca/Fe-phytate as the sole P source, which sheds light onto improving its application in phytoremediation of As-contaminated sites.

Copper enhanced arsenic-accumulation in As-hyperaccumulator Pteris vittata by upregulating its gene expression for As uptake, translocation, and sequestration.

In contaminated soils, arsenic (As) often co-exists with copper (Cu). However, its effects on As accumulation and the related mechanisms in As-hyperaccumulator Pteris vittata remain unclear. In this study, P. vittata plants were exposed to 50 µM As and/or 50 µM Cu under hydroponics to investigate the effects of Cu on plant growth and As accumulation, as well as gene expression related to arsenic uptake (P transporters), reduction (arsenate reductases), and translocation and sequestration (arsenite antiporters). After 14 d of growth and compared to the As treatment, the As concentration in P. vittata fronds increased by 1.4-times from 793 to 1131 mg·kg-1 and its biomass increased by 1.2-fold from 18.0 to 21.1 g·plant-1 in the As+Cu treatment. Copper-enhanced As accumulation was probably due to upregulated gene expressions related to As-metabolisms including As uptake (1.9-fold in P transporter PvPht1;3), translocation (2.1-2.4 fold in arsenite antiporters PvACR3/3;2) and sequestration (1.5-2.0 fold in arsenite antiporters PvACR3;1/3;3). Our results suggest that moderate amount of Cu can help to increase the As accumulation efficiency in P. vittata, which has implication in its application in phytoremedation in As and Cu co-contaminated soils.

Analysis of a delayed diagnosis of carotid artery aneurysm presenting as a parapharyngeal space infection.

It is very rare for extracranial carotid artery dissection to present as a carotid pseudoaneurysm. A delayed diagnosis and delayed treatment will lead to rupture of carotid pseudoaneurysm and massive hemorrhage and death. In this paper, we reviewed the progress of the disease in one patient and reviewed the relevant literature reports to understand the characteristics of the disease. The patient had two consultations within the otolaryngology department. The patient later showed signs of infection in the parapharyngeal space and then died of an aneurysmal rupture and massive hemorrhage.

[Anti-EGFR monoclonal antibodies in recurrent and/or metastatic head and neck squamous cell carcinoma: a meta-analysis].

OBJECTIVE: To systematically review the literature regarding the effectiveness and adverse reaction of epidermal growth factor receptor-monoclonal antibodies (RGFR-mAbs) in improving the prognosis of R/M HNSCC so as to develop evidence-based recommendations for treatment. METHODS: Comprehensively searches were performed for the databases of CBM, PubMed, Embase and Cochrane to identify the published studies on the effect of RGFR-mAbs in recurrent and/or metastatic head and neck squamous carcinoma (R/M HNSCC) patients. Primary outcomes included overall survival (OS), progression-free survival (PFS) and overall response rate (ORR). And secondary outcomes included such severe adverse events (grade III-IV) as neutropenia, anemia, thrombocytopenia, skin reactions, hypokalemia, vomiting and hypomagnesemia, etc. RESULTS: A meta-analysis was conducted for 5 randomized controlled trials involving a total of 1 615 patients. Pooled data suggested the efficacies of EGFR-mAbs in R/M HNSCC patients. And adding EGFR-mAbs to conventional therapy led to significantly improved efficacies for R/M HNSCC (ORR: RR=1.61, 95% CI: 1.34-1.92, P<0.001; PFS: HR=0.68, 95% CI: 0.61-0.76, P<0.001; OS: HR=0.84, 95% CI: 0.75-0.95, P=0.004). Adverse events were comparable between EGFR-mAbs and control groups, except for increased incidence in skin reactions, hypomagnesemia, anorexia, exsiccosis and thrombogenesis. CONCLUSIONS: Existing randomized controlled trials support the efficacies of EGFR-mAbs for R/M HNSCC. During Mabs therapy, skin reactions and hypomagnesemia should be closely monitored.

[Anti-EGFR monoclonal antibodies in locally advanced head and neck squamous cell carcinoma: a Meta-analysis].

OBJECTIVE: To perform a Meta-analysis of all randomized controlled trials that compared the efficacy and adverse events profile of Mabs for LA HNSCC. METHOD: Several databases were searched, including CBM, PUBMED, EMBASE, and CENTRAL. Primary outcomes included overall response rate (ORR), overall survival (OS), progression-free survival (PFS). Secondary outcomes included serious adverse events, such as grade 3-4 skin reaction, dysphagia, mucositis, and nausea/vomiting. The results were expressed as relative ratio (RR) or hazard rate (HR) with their corresponding 95% CI. RESULT: The final analysis included 10 trials. The primary analyses indicated that Mabs did not improve ORR and PFS, except OS for locoregionally advanced (LA) HNSCC [ORR 1.21, 95% CI (0.97 - 1.49); PFS 0.87, 95% CI (0.75 - 1.01); OS 0.82, 95% CI (0.71 - 0.95)]. Analysis of adverse effects demonstrated that grade 3 - 4 skin reaction ERR 1.87, 95% CI (1.11 - 3.16)] was statistically significantly associated with Mabs except dysphagia ERR 0. 95, 95% CI (0.75 - 1.19)], Mucositis ERR 1.03, 95% CI (0.67 - 1.57)], and nausea/vomiting ERR 1.15, 95% CI (0.71 - 1.86)]. CONCLUSION: Anti-EGFR Mabs may be satisfactory for improving OS of LA HNSCC. During the Mabs therapy, skin reaction should be much more monitored.

[Clinicopathologic features and risk factors of bilateral cervical lymph node metastasis in head and neck squamous cell carcinoma].

OBJECTIVE: To investigate the clinicopathologic features and associated risk factors for bilateral neck node metastasis (BNM) in head and neck squamous cell carcinoma (HNSCC). METHODS: Two hundred eighty-six cases with HNSCC were retrospectively studied, including 83 cases of oral tongue cancers, 101 cases of hypopharyngeal cancers and 102 cases of supraglottic laryngeal cancers. All patients had unilateral or bilateral cervical lymph node metastasis confirmed by postoperative pathologic examinations. The following factors were evaluated to determine the risk for BNM in HNSCC: T staging, size, location, trans-midline condition, growth pattern, pathologic grading and infiltration of primary tumors; N staging; the size, number and extracapsular spread (ECS) of ipsilateral metastatic nodes; the number of involved levels on the ipsilateral neck. Chi-square test and logistic regression test were used for statistical analysis. RESULTS: BNM was found in 86 (30.1%) of 286 patients with HNSCC, including 52 (18.2%) cases of contralateral occult neck node metastasis. The incidence of BNM was 35.6% (36/101) in hypopharyngeal cancer, 31.4% (32/102) in supraglottic laryngeal cancer and 21.7% (18/83) in oral tongue cancer, respectively. N staging, the number and ECS of ipsilateral metastatic nodes, and the number of involved levels on the ipsilateral neck were important factors contributing to BNM. Multiple logistic regression analysis revealed that midline passing of primary tumor was associated with BNM in oral tongue cancer. The midline passing and ECS of ipsilateral metastatic node were key factors for BNM in hypopharyngeal and supraglottic laryngeal cancers. T staging, size and midline passing of primary tumor were closely related to BNM in oral tongue cancer. T staging and midline passing were associated with BNM in hypopharyngeal cancer. Midline passing was an important factor related to BNM in supraglottic laryngeal cancer. CONCLUSION: Midline passing of primary tumor is the most important factor determining BNM in hypopharyngeal, supraglottic laryngeal and oral tongue cancers, whereas ECS of ipsilateral metastatic node is the most important factor impacting BNM in hypopharyngeal and supraglottic laryngeal cancers.

[Preliminary report of laryngeal preservation in the surgical salvage of recurrent laryngeal cancer].

OBJECTIVE: To explore the plausibility of laryngeal preservation in salvage surgery of recurrent laryngeal carcinoma. METHODS: Comprehensive clinical and radiological assessments on a specific group of patients with recurrent laryngeal cancer and their relapsed tumors were carried out to determine the methods and indications of salvage surgery for preservation of laryngeal functions. Salvage surgery with preservation of larynx was performed in a selective of 36 laryngeal cancer patients with relapsed tumors in their larynges after radiotherapy or partial laryngectomies. All patients were regularly followed up after discharge from the hospital. Postoperative survival was calculated by Kaplan-Meier's method. RESULTS: Among various laryngeal preservation regimens given, a second transoral laser surgery was carried out in 4 cases, horizontal hemilaryngectomy in 4 cases, vertical hemilaryngectomy in 13 cases and Majer-Piquet's operation in 15 cases, respectively. Simultaneous neck dissection was conducted in 18 cases. Postoperative complications were encountered in 6 cases, most common of which were local infection and laryngeal fistula with no hospital mortality and other major morbidities. Five cases with immediate postoperative complications were cured with proper management. The remained one case undergone vertical partial laryngectomy for recurrence after tumor resection via laryngeal fissure received postoperative radiation due to positive surgical margin, and complicated laryngeal atresia and obstruction with loss of his laryngeal functions. Local recurrence was observed in 5 cases and simultaneous locoregional recurrence was seen in 1 case, with the resulting local control rate of 83.3% (30/36). The 3-year postoperative survival rate was 80.6%. The cause of death was tumor recurrence in 3 cases, distant metastasis in 3 cases and non-tumor-associated disease (heart attack) in 1 case, respectively. CONCLUSIONS: Salvage surgery with laryngeal preservation can be carried out in the selected cases with early or locally-confined recurrent lesions within the larynx, on the condition that the recurrent tumors be assessed thoroughly and indications for associated surgical techniques be evaluated properly.

[An objective evaluation of nasal airway obstruction by enlarged adenoids in children].

OBJECTIVE: To evaluate the clinical application value of nasal airway obstruction objectively and quantificationally by acoustic rhinometry (AR) in children with adenoid hypertrophy. METHOD: Thirty patients with adenoid hypertrophy were examined with AR and questionnaire at preoperative and eight weeks after surgery. The values of AR were compared with those of 27 normal controls. RESULT: There were significant differences between preoperative and postoperative in NAR and NPV (P < 0.01), no significant difference was observed between preoperative and postoperative in MCSA (P > 0.05); There were significant differences in NAR, NPV, MCSA between the patient group and the control group (P < 0.01); There were significant differences between postoperative and the control group in NPV and MCSA (P < 0.01), no significant difference was observed between postoperative and the control group in TNAR (P > 0.05); There was negative correlation between MCSA and symptom scores (r = -0. 519, P < 0.05). No significant correlation was observed between NAR and NPV and symptom scores (P > 0.05). CONCLUSION: Acoustic rhinometry was an objective and quantitative method for evaluating nasal airway in children with adenoid hypertrophy. In interpretation the relationships of the results of acoustic rhinometry reflection measurements and subjective symptoms, MCSA should be the main reference.

[Phonation assessment of voice restoration after laryngectomy].

OBJECTIVE: To take an objective phonation assessment for the patients who have taken the tracheo-esophageal (TE) shunt procedure after total laryngectomy. METHOD: Twenty-four patients after TE shunt procedure were selected as TE group. Esophageal speakers after total laryngectomy and normal subjects were considered as controls. All the subjects of three groups took part in the voice acoustic assessment and MPT measurement. Twenty TE speakers took part in intra-tracheal pressure measurement. TE speakers and esophageal speakers participated in the electronic laryngoscope examination. RESULT: There were no significant differences between TE group and esophageal group in every acoustic parameters, but there were very remarkable differences between TE group and normal subjects in jitter, shimmer, harmonics to noise ratio and normalized noise energy. The pressure of TE speakers for comfortable /a/ is (2.86 +/- 0.69) kPa. The pharyno-esophageal segment vibrated regularly in most alaryngeal speakers and shapes of neo-glottis of most alaryngeal speakers were circular. CONCLUSION: Acoustic parameters of TE speakers were similar to those of esophageal speakers, but the tone of TE speakers was more similar to the normal controls. Speaking of the patients after the TE shunt procedure is laborsaving.