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It is of critical importance for our understanding of speciation process to determine the forms of reproductive isolation and their relative importance in species divergence. Oryza nivara and O. rufipogon are direct ancestors of Asian cultivated rice and a progenitor-daughter species pair. Investigating the reproductive isolation between them provides insights into plant speciation and helps understanding of the rice domestication. Here, we quantitatively measured the major components of reproductive isolation between the two species based on common garden and crossing experiments for three pairs of sympatric populations in Nepal, Cambodia and Laos. We revealed significant differences in the flowering times between species pairs, with O. nivara flowering much earlier than O. rufipogon. A very weak reduction in seed set but no reduction in F1 viability and fertility were detected for the crosses between species relative to those within species. Moreover, we detected asymmetrical compatibility between species and found that emasculation significantly decreased pollination success in O. nivara but not in O. rufipogon. Our study demonstrates that the divergence between O. nivara and O. rufipogon is maintained almost entirely by the difference in flowering times and suggests that differential flowering times contribute to both habitat preferences and reproductive isolation between species.

Background: Adenoid hypertrophy (AH) is associated with pediatric chronic rhinosinusitis (pCRS), but its role in the inflammatory process of pCRS is unclear. It is thought that innate immunity gene expression is disrupted in the epithelium of patients with chronic rhinosinusitis (CRS), including antimicrobial peptides and pattern recognition receptors (PRRs). The aim of this preliminary study was to detect the expression of innate immunity genes in epithelial cells of hypertrophic adenoids with and without pCRS to better understand their role in pCRS. Methods: Nine pCRS patients and nine simple AH patients undergoing adenoidectomy were recruited for the study. Adenoidal epithelium was isolated, and real-time quantitative polymerase chain reaction (RT-qPCR) was employed to measure relative expression levels of the following messenger RNAs in hypertrophic adenoid epithelial cells of pediatric patients with and without CRS: Human β-defensin (HBD) 2 and 3, surfactant protein (SP)-A and D, toll-like receptors 1-10, nucleotide-binding oligomerization domain (NOD)-like receptors NOD 1, NOD 2, and NACHT, LRR and PYD domains-containing protein 3, retinoic acid-induced gene 1, melanoma differentiation-associated gene 5, and nuclear factor-κB (NF-κB). RT-qPCR data from two groups were analyzed by independent sample t -tests and Mann-Whitney U -tests. Results: The relative expression of SP-D in adenoidal epithelium of pCRS group was significantly lower than that in AH group (pCRS 0.73 ± 0.10 vs. AH 1.21 ± 0.15; P = 0.0173, t = 2.654). The relative expression levels of all tested PRRs and NF-κB, as well as HBD-2, HBD-3, and SP-A, showed no statistically significant differences in isolated adenoidal epithelium between pCRS group and AH group. Conclusions: Down-regulated SP-D levels in adenoidal epithelium may contribute to the development of pCRS. PRRs, however, are unlikely to play a significant role in the inflammatory process of pCRS.

Based on ANSYS, a finite elements method study is conducted on couple fields of fixed tube-sheet heat exchanger. On the basis on the calculating results, the paper tries to analyze and evaluate the reliability and parameter sensitivity of the couple field of fixed tube-sheet heat exchanger, so as to present references for the reliable design on the intensity of mechanical equipments.

C13H17N3OS, monoclinic, P1̅ (no. 2), a = 7.746(6) Å, b = 12.344(9) Å, c = 12.655(9) Å, α = 95.766(7)°, β = 98.007(7)°, γ = 101.595(13)°, V = 1163.4(15) Å3, Z = 2, R gt(F) = 0.0550, wR ref(F 2) = 0.1616, T = 296(2) K.

C16H20N4Ni, monoclinic, P21/n (no. 14), a = 7.6578(10) Å, b = 17.184(2) Å, c = 11.6581(15) Å, β = 100.837(2)°, V = 1506.7(3) Å3, Z = 4, R gt(F) = 0.0356, wR ref(F 2) = 0.0945, T = 296(2) K.

Leukokeratosis of the vocal cords is a clinical descriptive diagnosis, which includes a group of squamous intraepithelial lesions of the vocal cord mucosa. We investigated the clinical classification and treatment efficacy of leukokeratosis of the vocal cords.We conducted a retrospective analysis of the medical history, laryngoscopic examinations, morphological features under a surgical microscope, and pathology results of 360 cases of leukokeratosis of the vocal cords to examine correlations among treatment modalities, therapeutic effects, and clinical features.All cases were divided into four types based on symptoms, examination results, and treatment efficacies as follows: 21 patients had type I inflammatory leukoplakia and their vocal cord morphology and voice quality recovered after conservative therapies; 76 patients had type II frictional polyps and received CO2 laser submucosal cordectomy; 68 patients had type III sulcus vocalis and received mucosal slicing with dredging; and 195 cases had type IV simple leukokeratosis and received partial subligamental cordectomy with CO2 lasers or transmuscular cordectomy. Our treatment achieved a surgical cure rate of 90.9% (308/339), with a recurrence rate of 9.1% (31/339) and malignant transformation rate of 6.5% (22/339). All cancerous transformations occurred in type IV patients.Choosing conservative or CO2 laser surgery based on the morphological characteristics of squamous epithelial lesions of keratinized vocal cord mucosa can maximally protect voice quality, reduce complications, and improve the cure rate.

To discuss the clinical classification of the squamous intraepithelial lesions (SILs) of vocal cord and their outcomes after different therapeutic procedures.Three hundred and forty-three patients with the SILs of vocal cord were enrolled. Based on the history of the diseases, macroscopic appearance by video rhino aryngoscopic, stroboscopic and microlaryngoscopic examination, and pathological findings, the correlation of clinical features, treatment modalities and treatment effect of the vocal cord SILs were discussed.According to the morphological characteristics, 343 patients were divided into four types. TypeI, leukoplakia combined with inflammation (n = 19); type II, leukoplakia combined with polyps by friction (n = 72); type III, leukoplakia combined with sulcus vocalis (n = 64); type IV, keratosis (n = 188). Patients with type I lesions were treated by medications. The vocal cord configuration and the voice of the patients in type I returned to normal after treatment. Patients with type II, III, IV lesions were treated by CO(2) laser. Type II were treated by subepithelial cordectomy, type III by mucosa slicing with dredging, type IV by sub ligament cordectomy or trans muscular cordectomy. The cure rate of patients with type II, III, IV lesions was 90.7% (294/324) after single surgery, the recurrent rate was 9.3% (30/324). Twenty-one patients (11.2%), all in type IV, developed carcinogenesis. Eight cases were diagnosed in the first surgery and 13 cases in the second. Among the 13 cases diagnosed in the second surgery, 2 cases had partial laryngectomy for the third surgery.Since the squamous intraepithelial lesions of vocal cord manifested differently, conservative treatment or CO(2) laser surgery should be used. In this way, a less invasive procedure, better recovery of the voice and less complication could be expected.

Juvenile onset recurrent respiratory papillomatosis (JORRP) is a relatively rare disease. It affects the larynx in most cases. Because reports on JORRP to the lower respiratory tract (LRT) are few, we investigated clinical features of patients with a history of JORRP to analyze the risk factors of this disease.Data from 208 JORRP patients admitted to Beijing Tongren Hospital from January 2008 to December 2010 were reviewed. Gender, age at onset of symptoms, age at first surgery, duration of symptoms before the first surgical procedure, the number of surgical procedures, mean interval between surgical interventions, and the number of tracheotomies in patients with and without LRT spread of JORRP were analyzed. The data from patients with and without tracheotomy were recorded and compared. Two cases of primary tracheal papillomatosis were reviewed.Papillomas extension down to the LRT was observed in 46 children (22.1%). Patients with LRT papillomatosis had a shorter time from the onset of the symptoms until the first surgery, required significantly more surgical procedures, and had a shorter mean surgical interval. Tracheotomy was performed in 13/162 (8.0%) children with laryngeal papillomatosis vs. 36/46 (78.3%) children with LRT papillomatosis. After tracheotomy, 36/49 (73.5%) children developed LRT papillomatosis and 10/157 (6.4%) children who did not have a tracheotomy developed LRT papillomatosis. Patients with tracheotomy required a significantly higher number of surgical procedures. The younger the patient had a tracheotomy, the longer the duration of cannulation was.JORRP patients with LRT spread are prone to develop more aggressive disease. Tracheotomy resulted in a significant increase of LRT involvement.

To investigate the strategy of surgical management of juvenile on-set recurrent respiratory papillomatosis (JORRP) with trachea/bronchia involvement so as to decrease the complications of the surgery.Twenty four JORRP patients undergone surgery in Beijing Tongren Hospital were studied between January 2006 and February 2009. All of them had JORRP with trachea/bronchia involvement. Suspension laryngoscopic surgeries were performed using rigid bronchoscope and micro-debrider. High frequency jet ventilator was used to maintain the ventilation in general anesthesia. Excision of tumors, suction of the blood and ventilation were preformed alternately. A total of 149 times of surgeries were analyzed.The age of the patients was from 3 to 16 years old (median 6 years old). The age at diagnosis was from eight months to 10 years old (median 1.5 years old). Twenty of them had undergone tracheostomy and the age at tracheostomy was from 1 to 4 years old (median 2 years old). Twenty two of them had been graded as two-degree dyspnea preoperatively, one graded as three-degree dyspnea and one four-degree dyspnea. All subjects underwent more than one surgery. Two cases were intubated and sent to intensive care unit because of postoperative hypercapnia. One was sent to intensive care unit postoperatively because of preoperative phypoxemia and hypercapnia. All subjects were discharged without dyspnea. No death and complications occurred.Suspension laryngoscopic surgery using rigid bronchoscope and micro-debrider was a safe and effective strategy for the treatment of JORRP with trachea/bronchia involvement.

To evaluate the access to the frontal recess by identifying the agger nasi cell and uncinate process.Forty-seven patients (85 sides) who underwent endoscopic frontal sinus surgery in our department constituted the study population. Computed tomographic (CT) scans of the sinuses were obtained in coronal and axial views. The frontal ostium was identified by using agger nasi cell approach or identifying the uncinate process.The frontal sinus ostium was identified in 100% of patients (85 sides). After an average follow-up of 9 months, 41 sides of 49 sides (84%) had endoscopically healed sinuses by using agger nasi cell approach. And 21 sides of 36 sides (81%) had endoscopically healed sinuses by identifying the uncinate process.The agger nasi cell approach to the frontal recess gives an access and allows identification of the frontal ostium. In addition, it provides direct visualization with a 0 degree endoscope into the frontal recess.