Cerebellin-2 promotes endothelial-mesenchymal transition in hypoxic pulmonary hypertension rats by activating NF-κB/HIF-1α/Twist1 pathway

AIMS

Endothelial-mesenchymal transition (EndMT) is one of the critical factors leading to vascular remodeling in pulmonary hypertension (PH). Recent studies found that the expression of Cerebellin-2 (CBLN2) is significantly increased in the lung tissue of patients with PH, suggesting that CBLN2 may be closely related to the development of PH. This study aims to investigate the role and potential mechanism of CBLN2 in the hypoxia-induced EndMT of PH rats.

MATERIAL AND METHODS

Hypoxia-induced PH rat model or EndMT cell model was constructed to investigate the role of CBLN2 in the process of endothelial mesenchymal transition during PH. The effects of CBLN2 siRNA, KC7F2 (HIF-1α inhibitor), and PDTC (NF-κB inhibitor) on hypoxia-induced EndMT were observed to evaluate the potential mechanism of CBLN2 in promoting EndMT.

KEY FINDINGS

The right ventricular systolic pressure and pulmonary vascular remodeling index in hypoxia-treated rats were significantly increased. The transformation of endothelial cells (marked by CD31) to mesenchymal cells (marked by α-SMA) can be observed in the pulmonary vessels of PH rats, and the expression of CBLN2 in the intima was also significantly up-regulated. In the hypoxia-induced HPAECs, endothelial cell markers such as VE-cadherin and CD31 expression were significantly down-regulated, while mesenchymal-like cell markers such as α-SMA and vimentin were increased considerably, along with the increased expressions of CBLN2, p-p65, HIF-1α, and Twist1; CBLN2 siRNA, PDTC, and KC7F2 could inhibit those phenomena.

SIGNIFICANCE

CBLN2 can promote EndMT by activating NF-κB/HIF-1α/Twist1 pathway. Therefore, CBLN2 may be a new therapeutic target for PH.

Specific Selective Neck Dissection for Isolated Regional Failure in Nasopharyngeal Carcinoma after Radiation

BACKGROUND

To assess whether specific selective neck dissection (SND) with involved levels is a feasible treatment for isolated regional failure in nasopharyngeal carcinoma (NPC) after radiation.

MATERIAL AND METHODS

Between January 2011 and December 2019, a total of 46 patients were assigned to undergo SND in the Department of Head and Neck Surgery at our center. The dissection extent of specific SND usually only involved levels of lymph node sites for isolated regional failure; in addition, lesions of level II or III involved removing both level II and III lymph nodes. The patients' clinical, MRI and pathological characteristics, overall survival (OS), disease-free survival (DFS) and regional-free survival (RFS) were evaluated and analyzed.

RESULTS

Level II was the most commonly involved cervical nodal region in 28 neck dissection specimens (54.9%), followed by level III with positive nodes in 11 specimens (21.6%). Eleven patients (34.8%) had post-SND locoregional recurrence without distant metastasis. Of the patients, 7 patients (30.4%) had regional recurrence, and only one patient (2.8%) had lymph node recurrence on the side of SND. In addition, 8 patients (17.4%) had post-SND distant metastasis. The OS, DFS, and RFS of the patients were 76.1%, 58.7%, and 69.6%, respectively, at 3 years. The OS, DFS, and RFS values of patients who underwent SND were similar to those of patients who underwent comprehensive neck dissection (CND) and/or SND in published articles.

CONCLUSION

Specific SND was shown to be an effective and feasible treatment for isolated regional failure in NPC.

Effects of acellular dermal matrix on the prevention of complications and esthetic outcome after parotidectomy: A propensity score matched analysis

OBJECTIVE

The present study was designed to investigate whether acellular dermal matrix (ADM) grafts could prevent Frey's syndrome (FS) and improve esthetic scores following parotidectomy.

METHODS

From January 2015 to December 2019, 175 patients underwent parotidectomy. We divided the patients into two groups: the ADM group and the control group. We included in each group 30 patients according to a propensity score matched analysis.

RESULTS

FS was subjective in 1 patient (3%) from the ADM group and 9 patients (30%) from the control group (P=0.015). Patients in the ADM group had a subjective esthetic score of 6.1 + 1.7 compared with 5.2 + 1.7 in the control group. The subjective esthetic score for patients in the ADM group was higher than that for patients in the control group (P =0.040).

CONCLUSION

The present clinical study suggests that ADM grafts are effective in preventing FS and improving esthetic scores after parotidectomy.

Changing trends of deep neck infections in southern China: A review of 127 cases

This study aimed to review our experience with the clinical characteristics and management of deep neck infections (DNIs) and determine the changing trends of their characteristics over time in southern China. Patients diagnosed with a DNI between January 2009 and December 2018 were screened retrospectively for their demographic characteristics, etiology of infection, site of infection, microbiology, treatment, and complications. In total, 127 patients were included: 41 (32.3%) were treated between 2009 and 2013 (group A), and 86 (67.7%) were treated between 2014 and 2018 (group B). The most common site of infection in group A was the parapharyngeal space (15 patients, 36.6%), while that in group B involved multiple spaces (36 patients, 41.9%). The leucocyte count (×109 cells/L) was 13.23 ± 4.19 in group A and 16.04 ± 4.33 in group B (p < 0.001). Streptococcus viridans was the most common bacteria in both groups. The mean hospital stay was 21.46 ± 33.09 days in group A and 10.44 ± 6.19 days in group B. The rate of diabetes mellitus (DM) in group A was lower than that in group B (8/41 and 33/86, respectively; p = 0.034). Airway obstruction was the most common complication in both groups. DNIs are more likely to show multi-space involvement, affect more DM patients, and be associated with higher leucocyte counts over time. We infer that the duration from morbidity to admission and that from admission to operation play roles in the successful management of DNIs, possibly causing fewer complications, lower mortality rates, and shorter hospital stays. DM patients require increased attention.

Comparison of Ultrasonography and CT for Determining the Preoperative Benign or Malignant Nature of Thyroid Nodules: Diagnostic Performance According to Calcification

Background:

The present study was designed to investigate the presence or absence of calcification and whether calcification size affect the diagnostic accuracy of ultrasonography (US) and computed tomography (CT) in predicting the benign or malignant nature of thyroid nodules.

Material and Methods:

From May 2014 to April 2019, 445 patients underwent thyroid US and neck CT before thyroid surgery. In each case, US and CT were retrospectively examined by radiologists. We divided the patients into 3 groups according to the type of calcification: no calcification, microcalcification, and macrocalcification. And macrocalcification group divided into rim calcifications and non-rim calcifications groups. We evaluated the diagnostic accuracy of US and CT for differentiating malignant from benign thyroid nodules using histopathological results as a reference standard.

Results:

In the overall population, adding CT to US resulted in greater sensitivity, lower specificity, and lower accuracy in the prediction of the benign or malignant nature of nodules. In the group with no calcification, US had a significantly greater accuracy than CT and combined US/CT. In the group with macrocalcification, especially in rim calcifications, adding CT to US resulted in greater sensitivity than US, and CT exhibited greater sensitivity and accuracy than US.

Conclusion:

US is superior to CT for the prediction of the benign or malignant nature of nodules in thyroid lesions according to calcification and CT is also currently not recommended as a routine imaging tool for thyroid nodules. However, the superior sensitivity and accuracy of CT in lesions with macrocalcification especially in rim calcifications may enable CT to play a complementary role in identifying benign and malignant nodules.

[Clinical characteristics of patients with cervical vascular pseudoaneurysm after radiotherapy for nasopharyngeal carcinoma]

Objective:The aim of this study is to analyze the clinical features of the pseudoaneurysm of the cervical vascular in patients with nasopharyngeal carcinoma after radiotherapy, and to summarize the clinical signs of patients with cervical vascular aneurysm, and to provide a basis for improving the success rate of treatment. Method:Patients with hemorrhage disease were treated by digital subtraction angiography （DSA） after radiotherapy for nasopharyngeal carcinoma are included. According to the presence or absence of pseudoaneurysm （PSA）, patients are divided to pseudoaneurysm group （PSA group） and non-pseudoaneurysm group（non-PSA group）, analysis of gender, age, presence or absence of tumor recurrence, presence or absence of recurrent radiotherapy, history of nasopharyngeal surgery after radiotherapy, needed to open the airway before the interval therapy, time to the end of radiotherapy. Result:The rate of tumor recurrence was 80% （12/15） in patients with pseudoaneurysm and 60%（9/15） in recurrent radiotherapy, which was significantly higher than that in patients with non-pseudular aneurysms. The average time to the end of radiotherapy is 36.5 months in patients with pseudoaneurysm, significantly shorter than non-pseudoaneurysm patients（106.7 months）. Conclusion:The high-risk clinical features of patients with cervical vascular pseudoaneurysm include: ①recurrence of nasopharyngeal carcinoma; ②history of recurrent radiotherapy; ③interval time is shorter between the hemorrhage and the end of radiotherapy, usually taking place within a few months to two years after recurrent radiotherapy. Patients with the above characteristics need to be screened early, and the DSA should be used as early as possible to confirm the cervical vascular condition and effectively control the hemorrhage.

[The early therapeutic effect of low-dose clarithromycin for chronic nasosinusitis with nasal polyps]

Objective:To observe the early therapeutic effect of low-dose clarithromycin for chronic nasosinusitis with nasal polyps.Method:Clarithromycin was 250mg a day and budesonide nasal apray was once a day.Follow-up time was 12 weeks. The number of postoperative clarithromycin+budesonide nasal apray treatment group and simple budesonide nasal apray treatment group were forty. The early therapeutic effect of patients was assessed by SNOT-20 and EAS score before treatment,2 weeks,4 weeks,8 weeks,and 12 weeks.Result:Before treatment,at 2 weeks and 12 weeks,there was no significant difference between the two groups in the results of the SNOT-20 score. But there were significant differences at 4 weeks and 8 weeks.Before treatment and at 12 weeks, there was no statistically significant difference between the two groups in the results of the EAS score.But there were significant differences at 2 weeks,4 weeks,and 8 weeks.Conclusion:The early use of low-dose clarithromycin has a definite curative effect on patients of chronic rhinosinusitis with nasal polyps.The larger randomized controlled trials were still needed to verify the specific mechanism and optimal dosage.

[A cross-sectional study of the clinical features and physician visit patterns at onset of immunoglobulin G4 related disease]

OBJECTIVE

To comprehend clinical features and patient's physician visit patterns at onset of immunoglobulin G4 related disease (IgG4RD).

METHODS

In the study, 100 patients with IgG4RD who received treatments in the Department of Rheumatology and Immunology of Peking University People's Hospital from Apr. 1st, 2017 to Apr. 1st, 2018 were investigated, including gender, age, height, body weight, age of onset, physician visit history, primary history and how did the disease affected their life, etc. RESULTS: In this 100 IgG4RD cohort (57 males and 43 females), the male/female ratio was 1:0.75, the mean age of onset was (51.51±12.9) years, and the median duration was 49 months (ranging from 4 to 231 months). The onset age of males was significantly older than that of females (P<0.01). The manifestations showed that up to 69% patients had submaxillay glands lesion, 59% patients had lacrimal glands lesion, 28% patients had pancreas involvement and 28% patients had parotid glands involvement. The females had more lacrimal glands involvement (P<0.05). 62% patients were complicated with anaphylactic disease. The primary physician visit departments concentrated upon general surgery department (19/100), oral and maxillofacial surgery department (17/100), rheumatology and immunology department (16/100), ophthalmology department (15/100) and gastroenterology department (10/100). The departments where the confirmed diagnose was made concentrated upon rheumatology department (67/100),oral and maxillofacial surgery department (16/100) and gastroenterology department (7/100). The mean diagnosis duration after 2010 was (16.96±2.163) months, significantly shorter than that before 2010, which was (113.3±11.01) months. Before the definite diagnose was made, 43% patients underwent surgeries and 12% patients had more than one time surgeries. The patients whose first-visit department was a surgery department were more likely to undergo surgeries (P<0.01). 18% patients (18/100) stated that the disease had affected their work.

CONCLUSION

In this cohort of the IgG4RD patients, female is common and has earlier onset age than male. The major manifestations of IgG4RD are salivary glands, lacrimal glands and pancreas involvement. The common chief complains are salivary glands and lacrimal glands enlargement. Accompanied by anaphylactic disease is a marked manifestation of this disease. Delayed diagnoses are not rare, though this situation has been improved since 2010, and more attention still should be paid to the disease.

[Unilateral polyp originated from nasal septum: a case report]

Most polyps were originated from the contact areas of uncinate process, the middle turbinate or the ethmoid infundibulum. Polyp originated from nasal septum is extremely rare. We report a rare case of a 44-year old woman with unilateral polyp of nasal septum.

[Exploration of transoral robotic surgery in the treatment of pediatric obstructive sleep apnea-hypopnea syndrome]

Transoral robotic surgery (TORS) is a relatively new technique in the treatment of pediatric obstructive sleep apnea-hypopnea syndrome, which has been shown to be safe and feasible. TORS provides a minimally invasive, visualization method, which brings an unprecedented breakthrough in the treatment of pediatric obstructive sleep apnea-hypopnea syndrome. In this paper, the application and development prospect of TORS in the treatment of pediatric obstructive sleep apnea-hypopnea syndrome will be reviewed.

[The value of plasma EBV-DNA testing in high-risk group of nasopharyngeal carcinoma in the nasal endoscopy]

Objective:The aim of this study is to evaluate the level of plasma EBV DNA and nasal endoscopy in high risk population of nasopharyngeal carcinoma, and to explore the value of EBV DNA testing in nasal endoscopy. Method:The nasopharyngeal carcinoma was screened in High-incidence Area of Zhongshan City. EBV antibody was detected by ELISA, and 427 patients with high risk of nasopharyngeal carcinoma were identified. In the high risk population the plasma EBV-DNA was measured using Fluorescent quantitative PCR, and all patients were used nasal endoscopy in the first two years. The application value of EBV DNA and nasopharyngeal endoscopic biopsy were analyzed. Result:There were 427 NPC high risk population in first screening. The rates of nasopharyngeal biopsy in EBV DNA positive and EBV DNA negative population were 90.2% (55/61) and 13.9% (51/366), respectively. The rate of NPC nasopharyngeal biopsy in EBV DNA positive population was higher than that in EBV DNA negative population (P<0.01). The rate of NPC detection in EBV DNA positive group (60.7%) was higher than that (3.3%) in EBV DNA negative population (P<0.01). In first year follow up, there were 286 NPC high risk population. The rates of nasopharyngeal biopsy in EBV DNA positive and EBV DNA negative population were 91.2% (31/34) and 11.9% (30/252), respectively. The rate of NPC nasopharyngeal biopsy in EBV DNA positive population was higher than that in EBV DNA negative population (P<0.01). The rate of NPC detection in EBV DNA positive group (17.6%) was higher than that (1.6%) in EBV DNA negative population (P<0.01). The positive predicative value of serological risk assessment was 8.3% (59/713), but for NPC high risk group, adding quantitative analysis of plasma EBV DNA, the positive predicative value was 45.3% (43/95). The early diagnosis rates in EBV DNA positive and EBV DNA negative population were 79.1% (34/43) and 93.8% (15/16), respectively. There was no significant difference in early diagnosis rates in two groups (P>0.05). Conclusion:The positive rate of plasma EBV DNA in high risk group of nasopharyngeal carcinoma may be helpful for nasal endoscopic nasopharyngeal biopsy, which can greatly improve the positive predictive value of high risk population of nasopharyngeal carcinoma. For NPC high risk population, Therefore, EBV DNA positive population are the focus for NPC screening.

Ultrabithorax and abdominal-A specify the abdominal appendage in a dosage-dependent manner in silkworm, Bombyx mori

In insects, there is a considerable diversity in leg distribution on the body, including number, segmental arrangement, morphological identity and consequent function, but the genetic basis for these differences is not well understood. Here by positional cloning, we showed that a ~355 kb region, including Bombyx mori Ultrabithorax (BmUbx) and abdominal-A (Bmabd-A), was responsible for the silkworm mutant Kh-extra-crescents-like (E^Kh-l) that displayed additional thoracic limb-like legs on the first abdominal segment (A1) and occasionally on the second abdominal segment (A2). We found that BmUbx gene was downregulated at both messenger RNA level and protein level in E^Kh-l embryo, while its expression domain in the E^Kh-l embryo was almost the same as that in the wild type. Whereas Bmabd-A was upregulated at both levels and was ectopically overexpressed on the supernumerary leg-bearing segments in E^Kh-l. Compared with the previously reported E^cs-l mutant in which increased expression of both BmUbx and Bmabd-A gave rise to ectopic proleg-like appendages on the same segments, we propose that overexpressed Bmabd-A gene is capable to promote the outgrowth of extra leg appendages on A1 and A2 segments, whereas BmUbx gene is required to specify accurate morphologies of the ectopic legs in a dosage-dependent manner in silkworm. These results provide insights into how these hox genes regulate the leg morphologic diversity on the same segments.

[HER-2 expression and clinical significance in esophagogastric junction adenocarcinoma (Siewert type Ⅱ)]

OBJECTIVE

To investigate the human epidermal growth factor receptor-2 (HER-2) expression in esophagogastirc junction adenocarcinoma(Siewert type Ⅱ)and its clinical significance.

METHODS

A total of 180 patients with esophagogastric junction adenocarcinoma (Siewert type Ⅱ) were included in this study. The HER-2 expression was detected by immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH) analysis was performed to assess the HER-2 gene amplification in the IHC-positive and IHC-weak positive cases.

RESULTS

HER-2 overexpression (3+ ), weak positive (2+ ) and negative (1+ /0) was 11.7%(21/180), 8.9%(16/180), and 79.4%(143/180), respectively. The FISH analysis showed HER-2 gene amplification in 95.2%(20/21) of HER-2(3+ ) cases and 18.8% (3/16) of HER-2(2+ ) cases. The concordance rate between IHC and FISH was 95.2%. Overexpression of HER-2(3+ ) was associated with the tumor differentiation (P<0.05), and irrelevant to age, sex, pT stage, pN stage, pM stage and pTNM stage (P>0.05). The median overall survival time (OS) was 13 months in HER-2(3+ ) patients, significantly shorter than the 21 months in HER-2(2+ ) and HER-2(+ /-) cases (P<0.01).

CONCLUSIONS

Approximately 11.7% of the patients with esophagogastric junction adenocarcinoma (Siewert type Ⅱ) are HER-2-positive on IHC. HER-2 overexpression is associated with the tumor differentiation. IHC can be used as a screening test for the positive expression of HER-2 in the esophagogastirc junction adenocarcinoma (Siewert type Ⅱ). However, FISH detection can be used as a more reliable detection method.

[Phosphatase and tensin homolog deleted on chromosome ten/phosphatidyl Inositol 3-kinase/vascular endothelial growth factor signaling pathway changes in the rabbit Kawasaki disease model]

OBJECTIVE

To observe the changes of phosphatase and tensin homolog deleted on chromosome ten(PTEN)/ phosphatidyl Inositol 3-kinase(PI3K)/ vascular endothelial growth factor(VEGF)signaling pathway in a rabbit Kawasaki disease model.

METHODS

Model of Kawasaki disease was established in weanling Japanese big-eared rabbits with 10% bovine serum venous injection (2.5 ml/kg, 2 times, and 2 week's interval) through the ear. Twenty four rabbits were divided into 4 groups: control group (without injection of 10% bovine serum albumin, six rabbits); 1 day group (sacrificed a the second day after the establishment of Kawasaki disease models, six rabbits); 7 day group (sacrificed at the seventh day after establishment of Kawasaki disease model, six rabbits); 30 day group (sacrificed at the thirtieth day after establishment of Kawasaki disease model, six rabbits). Pathological analysis was performed on coronary artery tissue samples. The express of PTEN and PI3K were detected by immunohistochemistry. The levels of VEGF and CK were also examined with ELISA and white blood cells were counted.

RESULTS

(1) Coronary artery of model groups was thinner, distorted and had enlarged lumen. (2) PTEN expression in 1 d group, 7 d group and 30 d group were 58.5 ± 12.9, 73.2±9.9 and 109.6 ± 24.4, respectively, significantly higher than in the control group (25.5 ± 6.9, P<0.01 or 0.05). (3) The express of PI3K was significantly upregulated in 1 d group(57.2±11.1)and 7 d group(39.9±4.8) compared to control group(19.1±3.5, P<0.01 or 0.05). The expression level of PI3K in 30 d group was 18.8 ± 7.5, which was similar as control group (P>0.05) and significantly lower than 1 d and 7 d group (both P<0.05). (4) Similarly, the level of VEGF in 1 d group, 7 d group ((89.1 ± 15.5) ng/L, (76.9±9.9) ng/L) were significantly higher while it was significantly lower in 30 d group ((19.8 ± 4.4)ng/L) compared with the control group ((33.9 ± 6.7) ng/L, P<0.01 or 0.05). The level of VEGF in 7 d group was significantly lower than in 1 d group (P<0.05) and the level of VEGF was significantly lower in 30 d group than in 7 d group (P<0.01). (5)Creatine kinase levels were significantly higher in 30 d group than in control group (P<0.05) and there were no significantly different between control group, 1 d group and 7 d group(all P>0.05). (6)White blood cell count were significantly higher in 1 d group, 7 d group and 30 d group than in control group (all P<0.01).

CONCLUSION

The level of PTEN/PI3K/VEGF signaling pathway change after establishment of rabbit Kawasaki disease model and the signaling pathway might be involved in this model.

Observation of Kawasaki disease-related indexes and the study of relationship between myocardial enzyme changes and coronary artery lesions

OBJECTIVE

To discuss the significance of Kawasaki disease-related laboratory indicators and relationship between myocardial enzyme changes and myocardial enzyme changes in children with Kawasaki disease.

PATIENTS AND METHODS

Make an observation of C-reactive proteins and immune globulin changes in children with Kawasaki disease, and also a comparison about the myocardial enzyme changes between the children with myocardial enzyme changes and others without lesions.

RESULTS

Compare the study group before treatment with the control group of normal children, there are significant differences in the levels of CRP, IgG, and IgM, and the difference was statistically significant (p < 0.05); make a comparison about the levels of AST, LDH, CK, HB-DH, and CK-MB in the group with or without coronary artery lesions, the difference was not statistically significant (p > 0.05).

CONCLUSIONS

Relevant laboratory indices play an important role in the early diagnosis of Kawasaki disease. Myocardial injury and coronary artery lesions in children with Kawasaki disease have no correlation between each other, and there has an inconsistency characteristic.

[Clinical analysis of low grade myofibroblastic sarcoma in head and neck]

OBJECTIVE

To explore the clinical characteristic, the CT, MRI features, diagnosis and treatment of low grade myofibroblastic sarcoma in head and neck.

METHOD

Six cases of low grade myofibroblastic sarcoma in head and neck were diagnosis and reviewed retrospectively. Routine preoperative CT and MRI examination were performed.

RESULT

All cases were operated one case with radiotherapy before operation was given with a total dose of 60 Gy. The patients were follow-up for 6 months to 5 year and no recurrence was found. No complications occurred in 6 cases.

CONCLUSION

It has been confirmed in this research that LGMS is a low-grade malignangt tumor. It was difficult to make early diagnosis through frozen section. The final diagnosis depend on paraffin section and immunohistochemisty. Extended local excision with tumor-free margin is the treatment of choice.

First Report of the Root-Knot Nematode Meloidogyne arenaria Infecting Noni in China

Noni (Morinda citrifolia) is an important medicinal plant and its fruit and root are of high value. In recent years, noni has been cultivated widely on Hainan Island, China. A survey of eight commercial noni fields in four counties found that most fields had plants with symptoms consistent with damage caused by root-knot nematodes. Above-ground symptoms included reduced vigor, plant stunting, and chlorosis. Affected roots were galled, swollen, cracked, and rotten. Fruit loss associated with diseased plants was quantified as 85%. In each field, three samples were taken consisting of 15 cm wide × 20 cm deep soil (containing roots). The nematode population was extracted and quantified according to Barker (1). Nematodes were found in all soil and root samples with population densities ranging from 450 to 835 eggs and second-stage juveniles (J2s) per 200 g subsample of soil, and 685 to 985 eggs and J2s per 10 g sub-sample of fresh roots. Three single egg masses were respectively hand-picked from one sample of diseased noni roots and inoculated onto tomato plants grown with sterilized soil at 20 to 28°C in the greenhouse. After 8 weeks, nematodes were extracted from the roots of tomato plants and identified by morphology, enzyme analysis, and molecular characterization. Morphology of the female perineal patterns showed a low dorsal arch with large lateral lines separating the striae of the dorsal and ventral sectors, leading to the tail terminus; and wavy, coarse striae with forking at lateral lines and short irregular striae near the lateral lines. Enzyme analysis of the esterase phenotype was also typical of the A1 phenotype in M. arenaria. Based on the perineal pattern and esterase phenotype, the Meloidogyne species was identified as M. arenaria (Est A1) (3). Total genomic DNA was extracted from ca. 10 μl of packed second-stage juveniles (J2s) using the method of Cenis (2). The primers C2F3 (5'-GGTCAATGTTCAGAAATTTGTGG-3') and 1108 (5'-TACCTTTGACCAATCACGCT-3') (4) was used to amplify the intergenic region between COII and LrRNA genes of the mtDNA and an amplification product (1,700 bp) was obtained, similar to M. hispanica, M. incognita, and M. javanica. Root-knot nematodes (Meloidogyne spp.) have been reported to be cause disease on noni in Hawaii. However, to our knowledge, this is the first report of M. arenaria (Est A1) infecting noni in China. References: (1) K. R. Barker. Pp. 19 in: An Advanced Treatise on Meloidogyne. Vol. II, Methodology. K. R. Barker et al. eds. North Carolina State University Graphics, Raleigh, 1985. (2) J. L. Cenis. Phytopathology 83:76,1993. (3) P. E. Esbenshade and A. C. Triantaphyllou. J. Nematol. 17:6,1990. (4) T. O. Power and T. S. Harris J. Nematol. 25:1,1993.

Antennapedia is involved in the development of thoracic legs and segmentation in the silkworm, Bombyx mori

Homeotic genes, which are associated closely with body patterning of various species, specify segment identity. The Wedge eye-spot (Wes) is a new homeotic mutant located on the sixth linkage group. Homozygous Wes/Wes embryos are lethal and display a pair of antenna-like appendages under the mouthparts as well as fused thoracic segments. These mutants also exhibit a narrower eye-spot at the larval stage compared with the wild type. By positional cloning, we identified the candidate gene of the Wes locus, Bombyx mori Antennapedia (BmAntp). Two BmAntp transcripts were identified in the homozygote of the Wes mutant, including a normal form and an abnormal form with a 1570-bp insertion. Our data showed that the insertion element was a long interspersed nuclear element (LINE)-like transposon that destroyed the original open reading frame of BmAntp. Quantitative RT-PCR analysis showed that the expression levels of normal BmAntp transcripts were increased markedly in the Wes heterozygous larvae compared with the wild type. Furthermore, we performed RNAi of BmAntp and observed fused thoracic segments and defective thoracic legs in the developing embryos. Our results indicated that BmAntp is responsible for the Wes mutant and has an important role in determining the proper development of the thoracic segments. Our identification of a homeotic mutation in the silkworm is an important contribution to our understanding of the regulation of Hox genes at different levels of expression.