[Clinical study of 15 cases of primary non-immunodeficient central nervous system lymphoma in children]

Clinical data of 15 primary central nervous system lymphoma (PCNSL) children aged ≤18 years admitted to our hospital between May 2013 to May 2023 were retrospectively analyzed. Our goal was to summarize the clinical features of children and investigate the therapeutic effect of a high-dose methotrexate (HD-MTX) based chemotherapy regimen on this disease. The male-to-female ratio was 2.7∶1, and the median age was 7.2 (2.3-16.4) years at diagnosis. The initial clinical symptoms were primarily cranial hypertension, with imaging findings revealing multiple lesions. Pediatric PCNSL with normal immune function has a favorable prognosis with HD-MTX-based chemotherapy. Patients with a stable disease can be treated with minimal or no maintenance. HD-MTX-based chemotherapy remains effective when the disease progresses or recurs after an initial course of non-HD-MTX-based chemotherapy.

[Clinical study of mature B-cell lymphoma in 11 children with chromosome 11 long-arm abnormalities]

Objective: To explore the clinical, pathological, diagnostic, treatment, and prognostic features of children with mature B-cell lymphoma (MBCL) . Methods: This retrospective study included pediatric patients with MBCL with chromosome 11 long-arm abnormalities who were diagnosed and treated at our hospital from December 2018 to February 2023. Results: Among the 11 pediatric patients with MBCL, nine were male and two were female, with a median age of 9 (2-13) years and a median disease course of 1.8 (0.5-24) months. The clinical manifestations were cervical lymph node enlargement in four patients, nasal congestion and snoring in four patients, abdominal pain in two patients, and difficulty breathing in one patient. There were seven cases of Burkitt's lymphoma, two of follicular lymphoma, and two of advanced B-cell lymphoma according to the pathological morphology examination. No patients had central nervous system or bone marrow involvement, and no extensive metastasis was observed on B-ultrasound or positron emission tomography-computed tomography (PET/CT). One patient had a huge tumor lesion. The Revised International Pediatric Non-Hodgkin Lymphoma Staging System classified four patients as stage Ⅱ, five as stage Ⅲ, and two as stage Ⅳ. 11q probe detection showed five cases of 11q gain, three of 11q loss, and three of both gain and loss. FISH showed positive MYC expression in three patients, including eight with advanced B-cell lymphoma with 11q abnormalities and three with Burkitt's lymphoma with 11q abnormalities. According to the 2019 edition of the National Health Commission's diagnostic and treatment guidelines for invasive MBCL in children, one patient was classified as Group A, two as Group B, and eight as Group C. Early evaluation of the efficacy showed complete remission. After mid-term evaluation, the intensity of chemotherapy was reduced in Group B and Group C. Among two cases of chemotherapy, the remaining nine cases had a median follow-up of 32 (6-45) months, and none had event-related survival. Conclusion: The incidence of MBCL with 11q abnormalities in children is low, clinical symptoms are mild, and progression is slow. The absence of MYC, BCL2, BCL6 rearrangements, C-MYC negative and 11q abnormalities on FISH is an important diagnostic indicator, and reducing the intensity of chemotherapy can improve prognosis.

[Mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 regimen in the treatment of pediatric Burkitt lymphoma]

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ²=4.16, P=0.041) and group C2 (χ²=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ²=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.

[Application of endobronchial ultrasound in children: an analysis of 4 cases]

Objective: To investigate the feasibility, clinical efficacy and safety of endobronchial ultasound (EBUS) in children. Methods: The radiological features, EBUS images, pathological results and intraoperative and postoperative complications of 3 cases who underwent EBUS examination and 1 case who underwent EBUS guided transbronchial needle aspiration (EBUS-TBNA) were retrospectively analyzed. Results: Among the 4 cases, 2 were males and 2 were females, with the onset age of 7.4-9.2 years. The child who underwent successful EBUS-TBNA was presented with fever and diagnosed with mediastinal lymphadenopathy before the operation, and the postoperative pathology indicated histiocytic necrotic lymphadenitis (HNL). The other 3 children diagnosed with primary airway tumors, whose pre-operative CT imaging found no infiltration in extra-bronchial structures, had the masses resected through EBUS. According to postoperative pathological findings, two were diagnosed with mucoepidermoid carcinoma and one with bronchial leiomyoma. The lesions were located at the opening of the right main bronchus in 1 case and at the main airway in 2 cases. EBUS showed abnormal echogenicity of the tracheal wall in the 3 cases, including hyperechoic area in the water capsule and mucous layer, relatively hypoechoic area in the submucosal smooth muscle layer, hyperechoic area in the inner cartilage layer, hypoechoic in the cartilage layer and hyperechoic in the outer cartilage layer. In one case, structural disorder of the submucosal smooth muscle layer and partial disruption of the cartilage layer of the tracheal wall were found at the lesion site, while the other 2 cases had intact tracheal wall structure. There were no postoperative complications such as pneumothorax or hemoptysis in the 4 children. Conclusion: EBUS is a safe and feasible technique for evaluating mediastinal lymph node enlargement and the degree of airway wall infiltration in primary airway tumor.

Veno-venous extracorporeal membrane oxygenation successfully treated a case of severe pulmonary hemorrhage caused by leptospirosis

BACKGROUND

Pulmonary hemorrhage is an important complication of leptospirosis. Once acute respiratory distress syndrome (ARDS) occurs as a secondary condition, treatment is extremely difficult and the mortality rate is very high.

CASE PRESENTATION

The patient was a 49-year-old. He was admitted to the hospital because he had experienced a fever and cough for 4 days. Hemorrhage, respiratory failure, ARDS and other symptoms appeared soon after admission. Due to severe pulmonary hemorrhage secondary to ARDS, mechanical ventilation was performed through tracheal intubation. During intubation, the patient suffered cardiac arrest, and the patient's condition worsened. He was confirmed to have leptospirosis through second-generation sequencing of the alveolar lavage fluid. Finally, we successfully treated the patient with penicillin as an anti-infective medication and venous-venous extracorporeal membrane oxygenation (v-vECMO). To the best of our knowledge, this report is the first to describe the successful application of ECMO in mainland China.

CONCLUSIONS

Leptospirosis can induce serious but transient ARDS with a better prognosis than other causes of ARDS. Our patient was successfully treated with V-vECMO.

[Comparison of long-term efficacy between watch and wait strategy and total mesorectal excision in locally advanced rectal cancer patients with clinical complete response after neoadjuvant therapy]

Objective: To compare long-term efficacy between watch and wait (W&W) strategy and total mesorectal excision (TME) in patients who were diagnosed with locally advanced rectal cancer (LARC) and attained clinical complete response (cCR) after neoadjuvant chemoradiotherapy (nCRT). Methods: A retrospective cohort study was carried out. A total of 238 patients with stage II-III LARC exhibiting cCR after nCRT in Sun Yat-sen University Cancer Center from September 16, 2010 to January 9, 2018 were enrolled. Patients who were diagnosed with other malignant tumor within 5 years, did not receive regular follow-up in our center for more than 1 year and had no complete examination items after nCRT were excluded. Of 238 patients, 151 were male and 87 were female with a median age of 57 (27-83) years old. According to TNM stage, 61 cases were cII, 177 cases were cIII. Concurrent chemoradiotherapy (CCRT) was performed in 20 patients. CCRT plus induction/consolidated chemotherapy was performed in 218 patients. Intensity-modulated radiotherapy (IMRT) was applied to radiotherapy. The median radiation dose was 50 Gy/25 Fr for both the primary tumor and clinical target volumes, and the total dose was 45.0 to 50.6 Gy for 227 patients. In 27 patients, single-agent fluorouracil or capecitabine was used as concurrent chemotherapy. But in the other 211 patients, a combined regimen of oxaliplatin and fluorouracil or capecitabine was used. After nCRT, 59 and 179 patients received W&W (W&W group) and TME 6-12 weeks later (TME group), respectively. After the ending of treatment, patient was interviewed one time every 3 months and after 3 years, one time every six months. Overall survival (OS) rate, distant-metastasis-free survival (DMFS) rate, and local-recurrence-free survival (LRFS) rate were compared between two groups. The salvage treatment and sphincter preservation rate were analyzed. The survival curve was drawn with Kaplan-Meier method and evaluated by log-rank method. Results: In the cases treated with TME, the median interval from nCRT to surgery was 59 days. The postoperative pCR rate was 63.1%(113/179). The median follow-up time of the whole cohort was 41.8 (12.0-99.0) months. The 3-year and 5-year OS rates were 98.4% and 96.5%; the 3-year and 5-year LRFS rates were 96.5% and 96.5%; the 3- and 5-year DMFS rates were 91.0% and 87.9%, respectively. The 3-year OS rates in the W&W group and the TME group were 100% and 97.9%; the 5-year OS rates in W&W group and the TME group were 90.6% and 97.9% (P=0.339); The 3-year local recurrence rate (LRR) in the W&W group was 12.9% (7 cases recurred within 2 years), which was significanthy higher then that in the TME group (0.6%, P=0.003). Salvage surgery was successful in 5/6 cases. After salvage surgery, LRFS rate was not significantly different between the two groups (P=0.137). The 3-year DMFS rate in the W&W group and the TME group were 88.4% and 81.1%, whose difference was not significant (P=0.593). Recurrence with simultaneous metastasis was seen in 3/7 cases of the W&W group. The sphincter was preserved in 89.8% (53/59) of patients in the W&W group, which was significantly higher than 73.7% (132/179) in the TME group (P<0.001). When distance of tumor from the anal verge was ≤ 5 cm, the sphincter preservation rate (SPR) in the W&W group was 88.0% (44/50), which was significantly higher than the 54.4% (56/103) in the TME group (P<0.001). Conclusions: W&W is safe and feasible for patients with LARC and cCR after nCRT. The results should be verified by further clinical trials.

[Effect of silencing FABP3 gene on LPS-induced apoptosis and endoplasmic reticulum stress in alveolar epithelial cells]

Objective: To investigate the effect of silencing fatty acid binding protein 3 (FABP3) gene on lipopolysaccharide (LPS)-induced apoptosis and endoplasmic reticulum stress in alveolar epithelial cells A549. Methods: According to the processing method, A549 cells were divided into control group(A549 cells cultured for 24 h), LPS group (10 mg/L LPS treated A549 cells for 24 h), LPS+si-con group (10 mg/L LPS was used to treat A549 cells transfected with si-con for 24 h) and LPS+si-FABP3 group (10 mg/L LPS was used to treat A549 cells transfected with si-FABP3 for 24 h). Then quantitative real-time PCR was used to detect the level of FABP3, methylthiazoletrazolium was used to detect the cell proliferation, flow cytometry was used to detect the apoptosis, and Western Blot was used to detect the levels of FABP3, CyclinD1, cleaved-caspase-3, GRP78, ATF4, CHOP, cleaved-caspase-12 and p-Akt and PI3Kp110α protein expression. Enzyme-linked immunosorbent assay was used to detect the levels of IL-6, IL-8 and TNF-αlevels. Results: In the LPS group, FABP3 protein level (1.00±0.09) and mRNA (2.15±0.22), apoptosis rate [(26.1±2.6)%], inflammatory factor IL-6 [(554.4±55.4) ng/L], IL-8 [(389.3±38.5) ng/L] and TNF-α [(601.3±60.0) ng/L], cleaved-caspase-3 (1.00±0.11), GRP78 (1.05±0.11), ATF4 (1.20±0.12)), CHOP (1.05±0.10), cleaved-caspase-12 (1.10±0.11), p-Akt (0.88±0.08) and PI3Kp110α (0.75±0.08) protein levels were significantly higher than the control group [(0.53±0.05), (1.00±0.10), (4.5±0.5)%, (75.4±7.5) ng/L, (25.2±2.5) ng/L, (66.5±6.7) ng/L, (0.34±0.05), (0.35±0.05), (0.43±0.05), (0.37±0.04), (0.45±0.05), (0.16±0.04), (0.35±0.05)] (all P<0.05). Cell viability [(50.1±5.4)%] and CyclinD1 protein level (0.40±0.05) in LPS group were significantly lower than those in the control group [(100.1±12.4)%, (1.25±0.12)] (both P<0.05). Cell viability [(89.1±8.5)%] and CyclinD1 protein level (1.15±0.11) in LPS+si-FABP3 group were significantly higher than those in LPS+si-con group [(53.1±5.4)%, (0.42±0.05)] (both P<0.05). Apoptosis rate [(10.5±1.1)%], IL-6[(301.3±30.0) ng/L], IL-8[(189.4±19.0) ng/L], TNF-α [(400.1±40.1) ng/L], cleaved-caspase-3 (0.45±0.05), GRP78 (0.48±0.05), ATF4 (0.60±0.06), CHOP (0.55±0.05), cleaved-caspase-12 (0.60±0.06), p-Akt (0.50±0.05) and PI3Kp110α(0.45±0.05) in LPS+si-FABP3 group were significantly lower than those in LPS+si-con group [(28.1±2.8)%, (536.3±53.6) ng/L, (400.2±40.2) ng/L, (623.1±62.3) ng/L, (0.96±0.10), (1.02±0.10), (1.15±0.12), (1.10±0.11), (1.15±0.12), (0.90±0.09), (0.72±0.07)] (all P<0.05). Conclusion: Silencing FABP3 gene can inhibit LPS-induced alveolar epithelial cell apoptosis and endoplasmic reticulum stress, which may act by inhibiting the PI3K/Akt signaling pathway.

[Clinical characteristics of 46 pediatric diffuse large B-cell lymphoma and treatment outcome]

Objective: To summarize the clinical data of diffuse large B-cell lymphoma (DLBCL) in children and to evaluate the efficacy of Beijing Children's Hospital B cell lymphoma protocol in the treatment of pediatric DLBCL. Methods: The data (clinical, pathology, lab and image data) of 46 pediatric DLBCL admitted to the treatment group of Beijing Children's Hospital from January 2005 to June 2017 were collected and analyzed retrospectively. According to the risk factors of staging, existence of poor prognosis genes and giant tumors, stratified treatment was carried out according to the international standard modified LMB89 regimen with high dose and short course. The Kaplan-Meier method was used to calculate the event free survival (EFS) and the overall survival (OS). Results: (1) Among the 46 cases, there were 33 males and 13 females. The median age was 8.0 years. The time from the initial symptom onset to the diagnosis was more than 15 days in 45 children. Fourteen cases had B group symptoms (fever, night sweat, and weight lost), 25 cases had extranodal disease, 39 cases were stage Ⅲ and Ⅳ, 12 cases had bone marrow involvement, 3 cases had jawbone involvement. Thirty cases were group B and 16 cases were group C in the treatment group. (2) Initial symptoms: 6 cases had cervical mass, 20 cases had abdominal mass, 10 had abdominal pain with acute abdomen, 8 cases had fever, 2 cases had snore or upper respiratory tract obstruction. (3) Pathology result: 40 cases were germinal center B cell DLBCL, 6 cases were non germinal center B cell DLBCL, no case had the MYC gene rupture, double hit lymphoma and triple hit lymphoma. (4) Complication and evaluation: the tumor lysis syndrome was seen in 3 cases initially, severe infection and delayed treatment was seen in 1 case, no treatment related death. The first evaluation showed all cases were sensitive to chemotherapy (shrink>25%), the second evaluation showed 1 case had residual disease, the others were complete remission. (5) Treatment and outcome: the 5 year-EFS was the same with 5 year-OS, both were (97.8±2.2) %. Two cases relapsed after treatment off, early relapse was seen in 1 case, and died because of abandoning treatment. Late relapse was seen in 1 case and got a complete remission after Rituximab+group C protocol treatment. Conclusions: Pediatric DLBCL was common in school aged boys, most cases were at middle and late stage at the time of diagnosis. DLBCL had a good prognosis after the treatment with Beijing Children's Hospital's B cell lymphoma protocol, but late relapse could be seen.

[Clinical analysis of methylmalonic acidemia and hyperhomocysteinemia with diffuse lung disease as an initial or main presentation]

Objective: To improve the awareness of methylmalonic acidemia and hyperhomocysteinemia with diffuse lung disease as an initial or main presentation. Methods: A retrospective analysis of the clinical manifestations, radiological features, laboratory tests, genetic variations, treatments and prognoses was conducted in six children presented with diffuse lung disease and finally diagnosed with methylmalonic acidemia and hyperhomocysteinemia in Ward 2 of Department of Respiratory Diseases, Beijing Children's Hospital, from August 2017 to November 2018. Results: Six children were included in this study. Two children were male and four were female. The average age of onset was 28 months. The mean age at diagnosis was 34 months. The average interval from onset to diagnosis was 6 months. Four children who underwent genetic tests were found to have variants of gene MMACHC and diagnosed with CblC type. All children had respiratory symptoms and signs as initial or main presentation, which were tachypnea (5 cases), exercise intolerance (5 cases), cough (4 cases), cyanosis (4 cases), clubbing (4 cases), dyspnea (3 cases) and retractions (3 cases). Pulmonary arterial hypertension was found in all six children. Pericardial effusion (4 cases), kidney involvement (3 cases), nervous system involvement (3 cases), gastrointestinal system involvement (3 cases) and anemia (2 cases) also coexisted. The high resolution computed tomography (HRCT) features included dilated pulmonary artery (6 cases), ground-glass opacities (4 cases), diffuse poorly defined ground-glass centrilobular nodules (3 cases), pleural effusion (3 cases), thickening of interlobular septum (2 cases), etc. All children had an elevated concentration of methylmalonic acid in urine and homocysteine in plasma. Genetic tests were performed in four patients, and MMACHC genetic mutations were found in all of them. Clinical manifestations, HRCT features and pulmonary arterial hypertension turned better in five children after treatment. One patient who was not regularly followed-up died. Conclusions: Pulmonary involvement including diffuse lung disease and pulmonary arterial hypertension could coexist with methylmalonic acidemia and hyperhomocysteinemia, which may have respiratory symptoms and signs as the initial or main presentation. Characteristic HRCT features were found in some patients. Plasma homocysteine test is a quick method for screening the disease in children with diffuse lung disease and (or) pulmonary arterial hypertension. Both diffuse lung disease and pulmonary arterial hypertension may turn better after treatment.

[Clinical and prognostic analysis of 186 children with Burkitt's lymphoma]

Objective: To analyze the clinical features and prognostic factors of childhood Burkitt's lymphoma and to summarize the therapeutic effect of the mature B-cell lymphoma regimen of Beijing Children's Hospital. Methods: It was a retrospective study. From January 2007 to December 2015, 186 patients below 18 years of age with newly diagnosed, untreated Burkitt's lymphoma were enrolled. Three cases were eliminated because of the abandonment of the treatment and 183 cases were stratified and treated according to the mature B-cell lymphoma regimen of Beijing Children's Hospital, groups were as follows: A, n=1; B, n=59; C, n=123 and 97 patients in group C received combined rituximab therapy during the treatment. The clinical features and therapeutic effects of patients were analyzed, overall survival (OS) and event-free survival (EFS) were estimated by the Kaplan-Meier method. COX regression was used to identify the prognostic factors. Results: The median age at diagnosis was 5 (1-14) years. There were 159 males (85.5%) and 27 females (14.5%) , the male-to-female ratio was 5.9∶1. A total of 174 cases (93.5%) evolved to stage Ⅲ and Ⅳ. Eight cases did not achieve remission and progressed to death, 9 cases relapsed. Only 5 patients (2.7%) died of treatment-related complications. With a median follow-up time of 48.0 (0.5-128.0) months, the 5-year OS rate and EFS rate were (89.1±2.3) % and (87.8±2.5) %. There was significant difference in the 5-year EFS rate between group B and C ( (94.9±2.9) % vs. (84.0±3.4) %, χ(2)=4.258, P=0.039). The 5-year EFS rate was (73.1±8.7) % and (86.7±3.7) % for patients in the group C treated with chemotherapy only and those treated with chemotherapy combined rituximab, but no statistical difference was found between them (χ(2)=3.360, P=0.067) . Central nervous system (CNS) involvement, insensitivity to early phase chemotherapy, residual diseases in mid-term evaluation were independent unfavorable prognostic factors (HR=6.167, 9.102, 3.104, 95%CI: 2.293-16.592, 1.837-45.107, 1.182-8.153) . Conclusions: The large dose, short course treatment of mature B-cell lymphoma regimen of Beijing Children's Hospital is effective for pediatric Burkitt's Lymphoma. Combined treatment with rituximab can improve the efficacy. CNS involvement, insensitivity to early phase chemotherapy, residual diseases in mid-term evaluation are associated with increased risk of poor prognosis.

Endoscopic titanium clip closure of gastric fistula after splenectomy: A case report

This report describes a 52-year-old male patient with blunt abdominal traumatic rupture of the spleen due to injuries sustained in an automobile accident. Following splenectomy, the patient developed a gastric fistula. He underwent a long period of conservative treatment, including antibiotics and total parenteral nutrition, which was ineffective. The fistula could not be closed and titanium clip closure using a gastroscopy was then performed in order to close the fistula. After endoscopic therapy and clipping surgery, the patient’s general condition improved significantly, and he had no post-procedural abdominal complications. On post-clipping day 6, the gastric fistula was completely closed as shown by X-ray examination of the upper digestive tract. The patient was discharged from hospital and no complications were observed during the six-month follow-up period. Our report suggests that titanium clip closure using endoscopy may be the choice of treatment in patients with a gastric fistula.

Supplementation with CTGF, SDF1, NGF, and HGF promotes ovine in vitro oocyte maturation and early embryo development

The strategies for improving the in vitro maturation (IVM) of domestic animal oocytes focus on promoting nuclear and cytoplasmic maturation. The identification of paracrine factors and their supplementation in the culture medium represent effective approaches for oocyte maturation and embryo development. This study investigated the effects of paracrine factor supplementation including connective tissue growth factor (CTGF), nerve growth factor (NGF), hepatocyte growth factor (HGF), and stromal derived factor 1 (SDF1) on ovine oocytes and early parthenogenetic embryos using an in vitro culture system. First, we identified the optimal concentrations of CTGF (30 ng/mL), SDF1 (10 ng/mL), NGF (3 ng/mL), and HGF (100 ng/mL) for promoting oocyte maturation, which combined, induced nuclear maturation in 94.19% of oocytes. This combination also promoted cumulus cell expansion and inhibited oocyte/cumulus apoptosis, while enabling a larger proportion (33.04%) of embryos to develop into blastocysts than in the controls and prevented embryo apoptosis. These novel findings demonstrate that the paracrine factors CTGF, SDF1, NGF, and HGF facilitate ovine oocyte and early parthenogenetic embryo development in vitro. Thus, supplementation with these factors may help optimize the IVM of ovine oocytes and early parthenogenetic embryo development strategies.

[Clinical features and diagnosis of childhood leukoencephalopathy with cerebral calcifications and cysts in four cases]

Objective: To investigate the clinical features and diagnostic bases of childhood leukoencephalopathy with cerebral calcifications and cysts (LCC). Methods: The clinical data involving manifestations and laboratory examinations of 4 children with LCC admitted to Beijing Children's Hospital Affiliated to Capital Medical University from 2012 to 2017 were retrospectively summarized. Each patient had a follow-up visit ranging from 4 months to 5 years and 9 months after initial examination. Results: Patients consisted of 2 males and 2 females, whose age of onset was respectively 2 years and 9 months, 6 years and 2 months, 7 years and 10 months, and 5 years and 1 month. The main clinical symptoms of these cases included headache, dizziness, partial seizure and claudication, and two of these cases had insidious onset. Cerebral calcifications and cysts with leukoencephalopathy were detected by neuroimaging in all patients. In addition, multifocal microhemorrhages and calcifications were observed by magnetic susceptibility-weighted imaging (SWI) series in 3 patients. Brain biopsy performed on 1 case disclosed a neuronal reduction in the cerebral cortex, loosening of focal white matter, multifocal lymphocyte infiltration, fresh hemorrhages, and gliosis, as well as angiomatous changes of blood vessels with hyalinized thicken-wall, stenotic or occlusive lumina and calcification deposits. The compound heterozygous mutations of n.*10G>A and n.82A>G in SNORD118 were identified in 1 case by target-capture next-generation sequencing. Sanger sequencing verified that the variant n.*10G>A was a novel mutation and it was of paternal-origin, while the variant n.82A>G was of maternal-origin, which had already been reported to be pathogenic to LCC. Follow-up study had shown continued partial seizure in 1 case and remissive claudication in another, while the remaining 2 cases had a relatively favorable outcome without obvious neurological symptoms at present time. Conclusions: The clinical manifestations of LCC are nonspecific, and the onset of the disease tends to be insidious. The triad neuroimaging findings of cerebral calcifications, cysts and leukoencephalopathy are essential to the diagnosis of the disease, and the signals of microhemorrhages revealed by SWI series provide another eloquent reference for the diagnosis. As biopsy is invasive and usually unavailable in the early stage, gene assessment, instead of pathological data, should be the gold standard in the diagnosis of LCC.

[Clinical pathologic characteristics and treatment outcomes of 19 relapsed pediatric B-cell lymphoma]

Objective: To review the clinical-pathology characteristics of 19 relapsed pediatric mature B cell lymphoma and to find the risk factors for recurrence and the feasible treatment after relapse. Method: Data of 212 pediatric B cell lymphomas cases in Beijing Children's Hospital from January 2006 to June 2015 were collected retrospectively. All the patients were treated according to the B cell lymphoma regimen of Beijing Children's Hospital. During the study period, 19 of 212 cases were relapsed; the clinio-pathological characteristics of relapsed patients before treatment and after relapse were analyzed retrospectively, the treatment outcomes after relapse were summarized and the patients were followed-up. Result: Nineteen of 212 cases had relapsed disease, for these relapsed patients: the median age at initial diagnosis was 5.5 years old, the median level of uric acid was 384(range, 121-713)μmol/L, the median level of lactate dehydrogenase(LDH) was 1 323(range, 146-6 370)U/L. Among 19 relapsed patients, 10 had local relapse and 9 had multiple relapses; 17 were Burkitt's lymphoma and 2 were diffuse large B cell lymphoma. Staging: 2 cases were stageⅡ, 3 cases were stage Ⅲ and 14 cases were stage Ⅳ. Risk group: 6 cases were group B and 13 cases were group C. Nine cases had bone marrow involvement and 10 cases had central nervous system(CNS) involvement. Acute tumor lysis syndrome was seen in 6 cases during the early treatment and 13 cases had delayed treatment. Treatment after relapse: 10 cases received further treatment after relapse (rituximab + 1-4 courses high intensity second-line chemotherapy), 3 cases received autologous stem cell transplantation. There was no chemotherapy or infection related death, 3 cases achieved complete remission (CR). For all the 212 patients, the median follow-up time was 47 (range, 1-131)months and the 5-year event free survival(EFS)rate was (89.4±0.2)%. For the 19 relapse cases, the 5-year overall survival (OS) rate was (21.1±0.1)%, CR rate after relapse was 30%, patients died of the progression of the primary disease, no treatment related death occurred. Univariate analyses showed that bulky disease, stage Ⅳ, maxillofacial and CNS involvement, LDH>1 000 U/L, delay treatment, day 7 evaluation shrink <25%, residual diseases after 3 months treatment are relapse risk factors (all P<0.01). Conclusion: Patients relapse during the treatment or at the early stage after the end of all chemotherapy have poor prognosis. So far there is no effective method for early relapse patients; the late relapse patients had the possibility of CR if they are sensitive to salvage treatment. In conclusion, to improve the outcome, the key point is to reduce the relapse.

[Abnormality of TOP2A expression and its gene copy number variations in neuroblastic tumors]

Objective: To detect TOP2A protein expression and gene copy number alterations, and to analyze related clinical and pathological implications in pediatric neuroblastic tumors (NT). Methods: Immunohistochemistry was used to detect TOP2A protein expression. Fluorescence in situ hybridization (FISH) was used to detect numerical aberrations of TOP2A. Results: TOP2A protein was expressed in 59.1%(52/88) of cases, which was associated with differentiation (P=0.006), Ki-67 index (P<0.01) and MKI (P=0.001). Twenty-eight cases (35.0%, 28/88) showed TOP2A gene amplification, which was correlated with the age (P<0.01), clinical stage (P=0.028), high risk group (P=0.001), Ki-67 index (P=0.040) and differentiation (P=0.014). Survival analysis showed that TOP2A expression was related to survival rate. Multivariate analyses showed that TOP2A expression was an independent predictor for poor prognosis (P=0.010). Conclusions: More than half of the cases show TOP2A expression, which is more likely associated with NB, high Ki-67 index and high MKI. Cases with TOP2A expression have shorter survivals and poorer prognosis. TOP2A amplification is seen in 35% and likely occurs in patients older than 18 months and at advanced INSS stages (Ⅲ and Ⅳ). As a target of the anthracycline-based adjuvant drugs, TOP2A test can be used to select patient with NT for the therapy.

[The clinical characteristics and outcomes of 16 Burkitt' s lymphoma with testicular involvement]

Objective: To analyze the clinical features and outcomes of Burkitt lymphoma with testicular involvement and study the efficiency of high dose methotrexate (HD-MTX: 5-8g/m2) in those patients without radiation therapy. Method: Retrospective analysis was conducted in 16 Burkitt's lymphoma cases with testicular lymphoma involvement between Jan 2009 and Dec 2014. We followed the BCH-NHL-2009 protocol, modified from FAB LMB 89 combined with rituximab. All patients were enrolled in high-risk group (treated by Group C protocol). Results: Of 137 Burkitt lymphoma, 16 (11.67% ) had testicular involvement. All the patients were in stage Ⅳ, the median age was 6.65 years (ranges: 2.25 to 13.5 years). 8 cases had bone marrow involvement, 9 with central nervous system involvement, 5 with bi-testicular involvement, 1 with EB virus infection (EBV-IgM+). The median follow-up was 31.8 months (ranges: 0.5 to 79 months). During the study period, 2 cases died, 1 due to the disease relapse, the other one due to chemo-related dead. 1 had disease relapse 32 months after off treatment; the other 13 cases were all event free survival. 3-year OS was 87.5%, 3-year EFS was 72.9%. We also found the level of testosterone in ten adolescent were normal before and after chemotherapy. Conclusion: For the Burkitt lymphoma with testicular involvement, we abandon radiotherapy, and administer HD-MTX to lower the toxicity. The short-term survival is better, long-term survival still needs to be clarified.

Multiple sequence alignment based on combining genetic algorithm with chaotic sequences

In bioinformatics, sequence alignment is one of the most common problems. Multiple sequence alignment is an NP (nondeterministic polynomial time) problem, which requires further study and exploration. The chaos optimization algorithm is a type of chaos theory, and a procedure for combining the genetic algorithm (GA), which uses ergodicity, and inherent randomness of chaotic iteration. It is an efficient method to solve the basic premature phenomenon of the GA. Applying the Logistic map to the GA and using chaotic sequences to carry out the chaotic perturbation can improve the convergence of the basic GA. In addition, the random tournament selection and optimal preservation strategy are used in the GA. Experimental evidence indicates good results for this process.

[Clinical analysis of two cases with diffuse pulmonary lymphatic disease]

OBJECTIVE

To analyze the clinical characteristics and diagnosis of 2 cases with diffuse pulmonary lymphatic disease.

METHOD

Clinical manifestations of the children were retrospectively analyzed. Two patients were both from Beijing Children Hospital in 2013 and 2014.Diffuse pulmonary lymphatic disease was diagnosed by pathology of pleura in case 1 and by lymphoscintigraphy in case 2.

RESULT

The first patient was a male aged 10-year-5-month who presented with a history of pleural effusion for 2 years. Examination revealed chylothorax and pericardial effusion. After pleural decortications and ligation of thoracic duct was performed, he still had recurrent chylothorax. Pathology of pleura revealed lymphangioma. Physical examination showed diminished breath sound and heart sounds. A bronchoscope revealed too much white viscous secretions. Thorax ultrasound revealed lymphangioma in bilateral lower thoracic cavity and post inferior mediastinum. Chest computed tomography showed diffuse thickening of the interlobular septa and bronchovascular bundle in both lungs, many punctate calcification in the lower field. Abdomen ultrasound revealed a small quantity seroperitoneum. Lymphoscintigraphy revealed radioactivity enhancement in bilateral thoracic cavity. The second patient was a female aged 6 years and 9 months, who presented with a history of recurrent cough for 2 years and 9 months. Physical examination showed normal result. Pulmonary function showed mixed ventilation function disturbance. A bronchoscopy showed extensive viscous secretions. Mediastinum, heart and abdomen were normal on ultrasound. Chest computed tomography showed diffuse thickening of the interlobular septa and bronchovascular bundle in both lungs and bilateral pleural thickening. Lymphoscintigraphy revealed diffuse lymphangiectasis in both lungs. Both patients received a diagnosis of diffuse pulmonary lymphatic disease. Case 1 who had died was diagnosed with diffuse pulmonary lymphangiomatosis. Case 2 had no exacerbation after 9 months' treatment with prednisone.

CONCLUSION

Diffuse pulmonary lymphatic disease might present with cough and shortness of breath and result in diffuse interstitial disease with thickening of the interlobular septa, refractory chylothorax, multiple lymphangioma in mediastinum, pericardial effusion and seroperitoneum. It could be diagnosed by pleura or lung tissue pathology and lymphoscintigraphy.

Novel polymorphic microsatellite markers for Bellamya and their application in population genetics of three species

Bellamya is a widely distributed freshwater snail genus in China; however, its genetic diversity is completely unknown. Sixty-five novel microsatellite loci were isolated and characterized from a microsatellite-enriched library of Bellamya aeruginosa genomic DNA. Most of the 65 loci were successfully amplified. We found high polymorphic information content values for these loci, ranging from 0.235 to 0.892. There were 3 to 12 alleles per locus, and the HE and HO varied from 0.425 to 0.953 and 0.026 to 1.000, respectively. Fifteen loci deviated significantly from Hardy-Weinberg equilibrium after Bonferroni's correction. All 65 SSR markers were tested in an additional five Bellamya species, and 96.9% of the 325 locus/taxon combinations tested resulted in cross-species amplification. Seven polymorphic microsatellite markers were randomly selected for comparison among nine populations of three species. All populations had moderate to high genetic diversity. In genetic distance-based cluster analysis, the populations of B. aeruginosa and B. dispiralis formed species-based clusters, whereas populations of B. angularia did not. The three examined Bellamya species could be differentiated using SSR markers. These microsatellite loci should be useful for genetic diversity analysis, analysis of phylogenetic relationship, and species delimitation of Bellamya.

Activation of the Wnt/beta-catenin signaling reporter in developing mouse olfactory nerve layer marks a specialized subgroup of olfactory ensheathing cells

Wnt reporter TOPgal mice carry a beta-galactosidase (betagal) gene under the control of the Wnt/beta-catenin signaling responsive elements. We found that the intensely immunolabeled betagal+ cells were co-immunolabeled with Nestin and formed a tangentially oriented single-cell layer in the "connecting or docking zone" where the olfactory sensory axons attached to the brain surface during mid-gestation. During early postnatal development, betagal+ cells were located in the inner olfactory nerve layer (ONLi) and co-labeled with olfactory ensheathing cell (OEC) markers S100beta and NPY but not with lineage-specific markers for neurons, oligodendrocytes, astrocytes, and microglia, demonstrating that the TOPgal marked a subpopulation of OECs. By confocal microscopy, we found that TOPgal activated processes extended along the developing glomerulus and formed multiple tunnel-like structures that ensheathe and bridge olfactory sensory axonal bundles from ONLi to the glomerulus, which may play a key role in glomerulus formation and convergent sorting of the peripheral olfactory axons.

Ocular coloboma and dorsoventral neuroretinal patterning defects in Lrp6 mutant eyes

Coloboma, an ocular birth defect seen in humans and other species, is caused by incomplete closure of the optic fissure. Here, we demonstrate that genetic deletion of Lrp6, a bottleneck coreceptor in the canonical Wnt signaling pathway, results in ocular coloboma and neuroretinal patterning defects in mice. The expression of ventral neuroretinal patterning gene Vax2 was conserved but with dorsally shifted expression domains; however, the dorsal neuroretinal patterning gene Tbx5 was lost in the Lrp6-mutant eyes at embryonic day 10.5. Both Bmp4 and phosphorylated Smad 1/5/8 were also significantly attenuated in the dorsal neuroretina. In addition, the retinoic acid synthesizing enzymes Raldh1 and Raldh3 were significantly changed in the mutant eyes. Our findings suggest that defective retinal patterning causes coloboma in the Lrp6-deficient mice, and that canonical Wnt signaling plays a primary role in dorsal neuroretinal patterning and related morphogenetic movements by regulation of both Bmp and retinoic acid signaling pathways.

Gene profiling involved in immature CD4+ T lymphocyte responsible for systemic lupus erythematosus

We attempted to characterize the genes expression of CD4+ T lymphocytes for the pathogenesis of systemic lupus erythematosus (SLE). Genomewide gene expression profiles of CD4+ T cells, which were isolated from the disease severe activity (T4-1s) and nonactivity (T4-2s) with an SLE patient by using long serial analysis of gene expression (LongSAGE). We picked out 289 genes matching to Unigene cluster with different expression more than four copies between T4-1s and T4-2s libraries and analyzed their roles from the collectedly published articles of PubMed by genes functional clustering. The genes functions were related to a diverse cellular process including: (1) most of these genes were associated with CD4+ T cells functions, particularly related to cellular developments; (2) Ras pathway genes as RANBP10, GMIP, RASGRP2 and ARL5 might be responsible for the abnormal development of CD4+ T cells of SLE; (3) HIG2, TCF7, KHSRP, WWP1, SMAD3, TLK2, AES, CCNI and PIM2 belong to Wnt/beta-catenin way, they could play roles in modulating proliferation and differentiation of T lymphocytes; (4) uncertain viral infections may initiate autoimmunity because high levels expression genes were detected in T4-1s such as TRIM22, IER2, ABCE1, DUT, G1P2, G1P3, HNRPUL1, EVER2, IFNAR1, TNFSF14, TMP21 and PVRL2; and (5) apoptosis relating genes as EIF3S8, SH3BGRL3, GPX4, TOSO, PFDN5, BIN1, XIAPAF1, TEGT and CUGBP2 may contribute to over uploading of selfantigens in SLE cells. Abnormalities findings of multiple genes expression involving with a variety of CD4+ T cells process might be meaningful to understanding the pathogenesis of SLE, and immature CD4+ T cells may be responsible for SLE.

Severe defects in dorsal thalamic development in low-density lipoprotein receptor-related protein-6 mutants

Mice with mutations in the Wnt coreceptor low-density lipoprotein receptor-related protein-6 (LRP6) have a smaller and severely disorganized dorsal thalamus and lack thalamocortical projections. Using molecular markers, we showed that most dorsal thalamic and epithalamic neurons were missing, and most of the major dorsal thalamic nuclei were not identifiable. However, the ventral thalamus was essentially unaffected, although the dorsal thalamic defect leads to rostral displacement of portions of the ventral thalamus. Analysis of younger embryos showed that epithalamic and dorsal thalamic neurons were not produced at early stages of development, whereas ventral thalamic neurons were still produced. These defects were accompanied by improper formation of the boundary between dorsal and ventral thalamus, the zona limitans interthalamica (ZLI). Furthermore, the expression of an early marker of posterior forebrain development that marks the compartment from the midbrain-hindbrain junction to the ZLI (including the future dorsal thalamus, pretectum, and midbrain) was disrupted, supporting the idea that diencephalic development is abnormal from very early in embryogenesis. This study provides compelling in vivo evidence that thalamic development requires normal activity of the LRP6-mediated canonical Wnt signaling pathway.

Wnt signaling mutants have decreased dentate granule cell production and radial glial scaffolding abnormalities

LRP6 mutant mice have generalized defects in the Wnt/beta-catenin signaling pathway because of the crucial function of LRP6 as a Wnt signaling co-receptor (Pinson et al., 2000). We examined the hippocampal phenotype of single LRP6 mutant mice as well as LRP6/Lef1 double mutant mice. LRP6 mutants had reduced production of dentate granule neurons and abnormalities of the radial glial scaffolding in the forming dentate gyrus. These defects were more severe with the addition of a single Lef1 null allele to an LRP6 null background. Pyramidal cell fields were unaffected in the LRP6, Lef1, or double mutants. The dentate defects were accompanied by decreased numbers of mitotic precursors in the migratory pathway to the dentate and in the displaced proliferative zone in the dentate itself. At earlier gestational ages, there was a reduction in the number of dentate granule cell progenitors in the dentate ventricular zone before the emigration of the earliest differentiated granule neurons and precursors to form the dentate anlage.

Genetic analysis, molecular tagging and mapping of the thermo-sensitive genic male-sterile gene (wtms1) in wheat

A thermo-sensitive genic male-sterile (TGMS) wheat line ( Triticum aestivum L.) BNY-S was obtained from the spontaneous mutant of BNY-F. Its fertility was decided by the temperature during the differentiation stage of the spikelets. BNY-S was completely sterile when the temperature was lower than 10 degrees C during the differentiation stage of the spikelets, but fertile when the temperature was higher than 10 degrees C. Genetic analysis indicated that the sterility of BNY-S was controlled by a single recessive gene, which was named as wtms1. An F(2) population, consisting of 3,000 individuals from the cross between BNY-S and Lankao 52-24, was used for genetic analysis and statistical analysis of the TGMS and, out of them, 158 sterile and 93 fertile extremes were present for molecular tagging and mapping of the wtms1 gene. SSR (simple sequence repeat) and AFLP (amplified fragment length polymorphism) techniques combined with BSA (bulked segregant analysis) were used to screen markers linked to the target gene. As a result, wtms1 was preliminarily mapped on chromosome 2B according to SSR analysis. In AFLP analysis, 14 polymorphic AFLP loci were identified with a linkage relation to the wtms1 gene. Then linkage analysis using the F(2) population showed that three of them, E: AAG/M: CTA(163), E: AGG/M: CTC(220) and E: ACA/M: CTA(160), were linked to the wtms1 gene relatively close to a genetic distance of 6.9 cM, 6.9 cM and 13.9 cM, respectively. Finally, the wtms1 gene was mapped between the SSR marker Xgwm 374 and the AFLP marker E: AAG/M: CTA(163) with the distance of 4.8 cM and 6.9 cM, respectively. A partial linkage map was constructed according the SSR and AFLP data.

Temporal and spatial profiles of ABCA2-expressing oligodendrocytes in the developing rat brain

ABCA2 protein belongs to the ABCA subclass of ATP-binding cassette (ABC) transporters proposed to exert critical functions in transmembrane transport of endogenous lipids. In this study, we found by immunoblot analyses that approximately 260 kDa of ABCA2 protein is expressed predominantly in oligodendrocytes, and that the expression of the protein is upregulated in the brain during maturation, especially between postnatal days 6 and 19. Parallel to the changes in expression of ABCA2, immunohistochemical analyses showed rapid spatial spread of ABCA2-immunolabeled oligodendrocytes in the brain during this period. These temporal and spatial changes in ABCA2 expression were in good agreement with findings in myeloarchitectonics reported previously. Further, double immunolabeling with ABCA2 and a major structural protein of myelin, myelin basic protein, demonstrated that onset of ABCA2 expression in oligodendrocytes coincides with the appearance of thick myelin segments immunolabeled with myelin basic protein. Because ABCA2 was abundantly expressed in adult cortex in white matter and gray matter, coexpression of ABCA2 and a marker for the oligodendroglial progenitors NG2 or platelet-derived growth factor alpha receptor was investigated. No cells coexpressing ABCA2 and the marker were observed, suggesting that ABCA2 is expressed predominantly in myelin-forming oligodendrocytes distinct from the adult oligodendroglial progenitors tested. These results suggested a role for ABCA2 in membrane transport of substrates such as the lipids that are closely linked to myelination processes.

ATP-binding cassette transporter ABCA2 (ABC2) expression in the developing spinal cord and PNS during myelination

We examined developmental characteristics of the ATP-binding cassette transporter ABCA2 (or ABC2) -expressing cells in rat spinal cord and peripheral nerves. In adult spinal cord, ABCA2 immunoreactivity was detected in lysosome-like organelles of mature oligodendrocyte cell bodies, and a single specific band was detected by Western blot analysis. In postnatal developing spinal cord, ABCA2 immunolabeling was first detected in a small number of cells restricted to the ventral marginal area and the dorsal funiculus at birth (P0). ABCA2-positive cells were co-immunolabeled by O4, a marker for late progenitor and immature oligodendrocytes. At the same time, myelin basic protein was apparent in the same restricted regions. The number of ABCA2 and O4 co-immunolabeled cells increased quickly in both dorsal and ventral regions from P2 and reached a peak at P8. After transient expression from P0 to P8, O4 labeling in white matter tracts decreased and disappeared. In contrast, ABCA2-positive oligodendrocytes persisted in gray and white matter throughout the spinal cord into adulthood. These data suggest a role for the ABCA2 transporter in maturation of oligodendrocyte lineage cells and the onset of myelination in the central nervous system. In addition, ABCA2 immunoreactivity was detected in the ciliated region of the ependyma in the central canal from early postnatal development. ABCA2 immunoreactivity was also detected in the Schwann cell lineage in developing spinal nerves and in adult trigeminal and sciatic nerves. ABCA2 was also expressed in numerous undetermined cells distributed in para-nerve connective tissues and nerve sheaths throughout early postnatal development. These data indicate multiple levels of involvement for ABCA2 in nervous system development especially with strong evidence for a role in myelination.

PACAP and its receptors exert pleiotropic effects in the nervous system by activating multiple signaling pathways

Pituitary adenylate cyclase-activating polypeptide (PACAP) was originally isolated from the ovine brain in 1989 as a novel hypothalamic hormone that potently activates adenylate cyclase to produce cyclic AMP in pituitary cells. This neuropeptide belongs to the secretin/glucagon/vasoactive intestinal peptide (VIP) superfamily, and exists in two amidated forms as PACAP38 (38-amino acid residues) and PACAP27 derived from the same precursor. The primary structure of PACAP has been remarkably conserved throughout evolution among tunicata, ichthyopsida, amphibia and mammalia, and a PACAP-like neuropeptide has also been determined in Drosophila. Both PACAP and its receptors are mainly distributed in the nervous and endocrine systems showing pleiotropic functions with high potency. There are three types of receptors with high PACAP-binding affinity and with different tissue-distribution patterns. All of them belong to G-protein-coupled receptor superfamily with seven transmembrane domains. PAC(1) is the PACAP-specific receptor and exists in at least eight splice variants which couple to different intracellular signal transduction pathways. VPAC(1) and VPAC(2) are the common receptors for both PACAP and VIP, which are coupled to adenylate cyclase. This review article presents and discusses an update on PACAP research and its pleiotropic physiological functions based on multiple receptor-mediated signaling mechanisms in both the central and peripheral nervous system, including the regulation of hypothalamic neurosecretion, homeostatic control of circadian clock and behavioral actions, involvement in learning and memory processes, neuroprotective effects such as anti-apoptosis and response to injury and inflammation, and neural ontogenetic functions on proliferation/differentiation processes from early stages.

The spatiotemporal relationship among Schwann cells, axons and postsynaptic acetylcholine receptor regions during muscle reinnervation in aged rats

To morphologically define the aging-related features during muscle reinnervation the spatiotemporal relationships among the major components of the neuromuscular junctions (NMJs) were investigated. A total of 64 rats, 30 adults (4 months old) and 34 aged adults (24 months old), were used. Between 1 and 12 weeks after sciatic nerve-crushing injury, cryosections of skeletal muscle were single or double labeled for S100, a marker of Schwann cells (SCs), for protein gene product 9.5, a neuronal marker, and for alpha-bungarotoxin (alpha-BT), a marker of the acetylcholine receptor site (AChR site), and then observed by confocal laser microscopy. The most obvious age changes were noted: (1) the regenerating SCs and axons were delayed in their arrival at the NMJ, (2) the dimensions of terminal SCs and AChR sites displayed a drastic and long-lasting drop (for terminal SCs, during 1-8 weeks; for AChR sites, during 1-12 weeks); (3) the degree of spatial overlap between AChR sites and terminal SCs was markedly low until 8 weeks post-crush; (4) damage and poor formation in the SCs, terminal axons and AChR sites, together with poor process extension from the terminal SC or terminal axon, were pronounced; (5) persistent aberrant changes, such as multiple innervation and terminal axon sprouting, together with poorly formed collateral innervation, nerve bundles, and NMJs, more frequently occurred in the later reinnervation period. Thus, with aging, regeneration is impaired during the period in which regenerating SC strands and axons extend into NMJs and the subsequent establishment of nerve-muscle contact is in progress. A complex set of morphological abnormalities between or among the TSCs, terminal axons, and AChR sites may be important in slowing of regeneration and reinnervation in aged motor endplates.

PACAP activates PKA, PKC and Ca(2+) signaling cascades in rat neuroepithelial cells

Several studies have reported that the PAC(1) receptor (PAC1-R), the specific receptor for PACAP, is expressed at early developmental stages. Here, we describe that the cytosolic Ca(2+) concentration ([Ca(2+)](i)) was increased by PACAP, but not VIP, in a concentration range from 10(-12) to 10(-8) M via the PAC(1)-R in isolated single cells from the rat neural fold. This activation of the cells by PACAP was mimicked by agonists and inhibited by antagonists of the cAMP/PKA and PLC/PKC cascades. These data indicate that PACAP/PAC(1)-R is linked to [Ca(2+)](i) signaling via two G-protein-coupled protein kinase pathways and may thereby play an important role in early neurodevelopment.

Application and modification of in situ RT-PCR for detection and cellular localization of PAC1-R splice variant mRnas in frozen brain sections

Many important biopolymers such as neurotransmitters, modulators, transporters and receptors are expressed in discrete regions of the brain or other tissues, and they often occur at extremely low concentrations; therefore, a sensitive detection system is required to map their distribution. To study the precise distribution patterns of the splice variants of the PAC1 receptor, which specifically binds pituitary adenylate cyclase-activating polypeptide (PACAP) with affinity in the nano- or picomolar range, we have applied an in situ reverse transcription-polymerase chain reaction (RT-PCR) technique in frozen tissue sections. We describe here a modified protocol using a single rTth enzyme, which can synthesize cDNA from RNA, then PCR amplifying it in a single reaction mixture by varying the times and temperatures of a thermal cycler. The primer pairs were the same as those used in the solution phase RT-PCR that had been used to obtain the expected bands of the amplified products previously. A nonradioactive labeling system with digoxigenin conjugated with peroxidase or fluorescence for signal detection was compared. The gene expression of two PAC1-R splice variants in the rat motor nucleus is first reported here.

Effect of prolactin and androgen on the expression of the female-attracting pheromone silefrin in the abdominal gland of the newt, Cynops ensicauda

Silefrin is a sodefrin-like, female-attracting pheromone comprising 10 amino acids that was isolated from the abdominal gland of the sword-tailed newt, Cynops ensicauda. Hormonal effects on the silefrin precursor mRNA expression and silefrin content in the abdominal gland were investigated in the present study by using Northern blot analysis and radioimmunoassay, respectively. In the abdominal gland of newts treated with prolactin (PRL) plus testosterone propionate (TP), silefrin precursor mRNA expression was markedly enhanced as compared with that in the newts injected with saline, PRL, or TP. Values for radioimmunoassayable silefrin content in the abdominal gland paralleled those for the silefrin precursor mRNA levels. Moreover, silefrin precursor mRNA signals, as revealed by in situ hybridization, as well as stainability of immunoreactive silefrin were much more intense in the epithelial cells of the abdominal gland of the PRL-plus-TP-treated animals than in those of controls. We thus conclude that PRL and androgen are important factors for enhancing silefrin synthesis.

Infection by microsporidia disrupts the host cell cycle

Microsporidia of the genus Encephalitozoon infect mammalian cells and have become a source of morbidity and mortality in immunocompromised humans. Encephalitozoon microsporidia develop and mature within parasitophorous vacuoles, enlarging the vacuole over time until it eventually occupies most of the cytoplasm of the host cell. The ability of the host cell to accommodate such a large burden for several days suggests that the parasite subverts normal host cell processes to ensure optimal environmental conditions for its growth and development. Since this environment would be threatened if cell division of the host cell occurred, we have formulated the hypothesis that infection with Encephalitozoon microsporidia induces an arrest in the cell cycle of the host cell. In support of this hypothesis, we have found that mitotic index and DNA duplication are reduced in infected cells as compared to uninfected cells. The number of host cell nuclei in S phase is increased. The levels of cyclin D1 and the percentage of cells in G1 are reduced; however, the levels of cyclin B1 are elevated even though the percentage of cells in G2/M is decreased. These results suggest that host cells infected with Encephalitozoon microsporidia are blocked at multiple points in the cell cycle.

Cloning, characterization and tissue distribution of the rat ATP-binding cassette (ABC) transporter ABC2/ABCA2

The ABC1 (ABCA) subfamily of the ATP-binding cassette (ABC) transporter superfamily has a structural feature that distinguishes it from other ABC transporters. Here we report the cloning, molecular characterization and tissue distribution of ABC2/ABCA2, which belongs to the ABC1 subfamily. Rat ABC2 is a protein of 2434 amino acids that has 44.5%, 40.0% and 40.8% identity with mouse ABC1/ABCA1, human ABC3/ABCA3 and human ABCR/ABCA4 respectively. Immunoblot analysis showed that proteins of 260 and 250 kDa were detected in COS-1 cells transfected with ABC2 having a haemagglutinin tag, while no band was detected in mock-transfected cells. After incubation with N-glycosidase F, the mobilities of the two proteins increased and a single band was detected, suggesting that ABC2 is a glycoprotein. Photoaffinity labelling with 8-azido-[alpha-(32)P]ATP confirmed that ATP binds to the ABC2 protein in the presence of Mg(2+). RNA blot analysis showed that ABC2 mRNA is most abundant in rat brain. Examination of brain by in situ hybridization determined that ABC2 is expressed at high levels in the white matter, indicating that it is expressed in the oligodendrocytes. ABC2, therefore, is a glycosylated ABC transporter protein, and may play an especially important role in the brain. In addition, the N-terminal 60-amino-acid sequence of the human ABC1, which was missing from previous reports, has been determined.

Morphological features of nerve terminal degeneration as part of the remodeling process in the motor endplate in adult muscles

With the exception of signs of retraction and withdrawal, there have been few morphological data concerning degenerated neural profiles in adult motor endplates. Here, investigation into the ultrastructure of the soleus motor endplates of adult rats (4 months old) turned up particular axonal degeneration in approximately 3% of the subjects. These axons occur as synaptic debris in the synaptic matrix of the motor endplate, adjacent to thin processes of the perisynaptic cells occupying the outermost layer of the motor endplate and were devoid of basal lamina. They often possessed dense-cored vesicles (50-80 nm). Axonal debris released from Schwann cell processes occurred during the period of acute sciatic neurectomy, when nerve terminals progressively disrupted within the motor endplate-associated Schwann cells. Finally, immunohistochemical staining for antibodies to label macrophages (ED1 or ED2) has shown that nerve fiber-associated macrophages are located near the motor endplate. The results suggest that during the course of endplate remodeling, a few parts of the terminal branches are disposed of through spontaneous collapse, subsequent release from the Schwann cell investment, and eventual ingestion by macrophages in the perisynaptic space.

Identification of the novel developmentally regulated gene, Bdm2, which is highly expressed in fetal rat brain

Most of the neurogenesis take place during the embryonic stage; the genes expressed predominantly in this stage may play important roles in the control of development of the central nervous system. Using a differential display method, we identified the novel rat gene, brain development-related molecule 2 (Bdm2), that is expressed more abundantly in the embryonic brain than in the adult brain. Full-length Bdm2 cDNA consists of 1842 base pairs (bp) and contains an open reading frame of 1260 bp. Northern blot analysis demonstrated that Bdm2 was strongly expressed in the late embryonic brain and was still detected at lower levels in an early postnatal period; in adults, Bdm2 mRNA was decreased to an undetectable level in brain, though the expression of this mRNA was revealed in other tissues. Level of Bdm2 mRNA was maintained during neuronal differentiation of mouse embryonal carcinoma cell P19, but decreased during the differentiation to glial and unidentified non-neuronal cells. In situ hybridization study demonstrated the wide distribution of Bdm2 mRNA in the embryonic brain; in the adult brain, the hybridization signals became more restricted to the hippocampus, olfactory bulb, cerebellum, and neocortex, almost coinciding with the regions where nascent and immature neurons are present. Thus, it appears likely that Bdm2 encodes a protein that is involved in both the regulation of growth of undifferentiated neural cells and the terminal differentiation of neuronal cells.

Cellular distribution of the splice variants of the receptor for pituitary adenylate cyclase-activating polypeptide (PAC(1)-R) in the rat brain by in situ RT-PCR

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic neuropeptide and its specific receptor (the PAC(1) receptor) is widely distributed in the rat brain. It has been reported that alternative splicing of the region encoding the third intracellular loop of the PAC(1) receptor generates six isoforms which are differentially coupled to signal transduction pathways, but the precise distribution and localization of these splice isoforms in the brain remain to be determined. Using the initial specific primer pairs which correspond to the 'hip' or 'hop' types of receptors for the solution-phase reverse transcription-polymerase chain reaction (RT-PCR), we demonstrated that the major splice variants of the PAC(1) receptor in various regions of the rat brain are the short splice isoform 'PAC(1)-R-s' which does not contain either the 'hip' or 'hop' cassette and the another splice isoform, 'PAC(1)-R-hop', which contains the 'hop' cassette. With an innovative molecular histochemical technique, in situ RT-PCR, we determined that these two splice isoforms are both intensely expressed in the mitral cells of the olfactory bulb, the Purkinje cells of the cerebellum, the pyramidal cells of the hippocampus and neocortex, and many neurons in the nuclei of hypothalamus and thalamus as well as other regions. The initial mapping of the cell type-specific expression of these two splice variants of the PAC(1) receptor provides the basis for a better understanding of the functional significance of the PAC(1)-R and its ligand PACAP in various brain regions.

Pituitary adenylate cyclase-activating polypeptide receptors during development: expression in the rat embryo at primitive streak stage

The distribution and localization of the pituitary adenylate cyclase-activating polypeptide (PACAP) receptor the PAC1 receptor (previously called the type 1 PACAP receptor or PVR1), which binds PACAP, but not vasoactive intestinal peptide, with high affinity] were first investigated in rats with in situ hybridization for its messenger RNA, and with immunohistochemical methods during prenatal and postnatal development. The expression of PACAP receptor messenger RNA was first detected in the rat embryo at the primitive streak stage as early as embryonic day 9, and it was intensely expressed in the neural plate. PACAP receptor messenger RNA was also intensely expressed in the neuroepithelia of the mesencephalon and rhombencephalon at embryonic day 11, and expressed in the basal telencephalon, hippocampal formation neuroepithelium, cortical neuroepithelium and cerebellar neuroepithelium after embryonic day 13. It was also expressed in the olfactory bulb neuroepithelium after embryonic day 16, and in mature regions of the older embryos. In postnatal developing brains, PACAP receptor messenger RNA was intensely expressed in the olfactory bulb, hippocampal formation, cerebellum and other scattered regions. The localization of PACAP receptor-like immunoreactivity coincided well with that of the gene transcripts. We also used reverse transcription-polymerase chain reaction methods to determine the expression of the splice variants of the PACAP receptor gene. At each ontogenetic stage of the rat from embryonic day 9 to postnatal day 60, two major products were detected with reverse transcription-polymerase chain reaction, a thick band (303 base pairs) corresponding to the short splice variant of the receptor that lacks both the "hip" and "hop" cassettes, and a thin band (387 base pairs) corresponding to the splice variant that contains one cassette of "hop" or "hip". There was no evidence for the other larger splice variants. Some of the amplified products were sequenced and found to have the exact sequences of "PACAP receptor" and "PACAP receptor-hopl", which are coupled to different signal transduction pathways. These results indicate that the PACAP receptor is actively expressed in different neuroepithelia from early developmental stages and expressed in various brain regions during prenatal and postnatal development, and that the major splice variants are "PACAP receptor" and "PACAP receptor-hopl". The initial mapping of ontogenetic localization of the PACAP receptor provides the basis for a better understanding of the functions of PACAP and its receptors during the development of the brain.

Changes in the distribution of peanut agglutinin (PNA) binding molecules during muscle reinnervation following nerve crush injury

Peanut agglutinin (PNA) staining during muscle reinnervation following a crushing injury of the sciatic nerve was performed in reference to the neural profiles immunolabeled with the PGP 9.5 antibody. PNA staining in the normal controls exhibited dots, granules, or lines along the length of the nerve fibers in the nerve trunk, but was faint or absent in the motor endplate. At seven days post-crush, PNA staining was detected around the vacuolated neural structures in the disorganized nerve trunk, but was still faint or absent in the motor endplate. At twenty-one days post-crush, when PGP 9.5-positive regenerating axons appeared in most of the motor endplates, PNA staining, either faint or strong, followed the pathway of the nerve fibers delineated by PGP 9.5-like immunoreactivity. During reinnervation to the motor endplates, PNA staining displayed signs of remodeling in the nerve trunk, such as marked variations in density and profile in the nerve fiber-associated dots or patches; it increased in intensity in the connective tissue covering the area of the motor endplate, as well as in the junctional myofiber surface. The structures recognizable by PNA coincided with components of the connective tissue such as collagen fibers and capillaries. Results suggest that: 1) the expression of PNA-binding molecules is dependent on the state of innervation, and 2) the spatiotemporal relationship between neural profiles and PNA staining provides sequences of axonal extension and subsequent nerve terminal maturation during regeneration in the motor endplate.

Delayed neuronal cell death in the rat hippocampus is mediated by the mitogen-activated protein kinase signal transduction pathway

Transient global ischemia caused by 5 min of cardiac arrest induced delayed neuronal cell death (apoptosis) in the CA1 region of the rat hippocampus. To characterize the molecular mechanisms that regulate apoptosis in vivo, the contributions to cell death of mitogen-activated protein kinase family members were examined in the hippocampal region after brain ischemia-reperfusion. Ischemia-reperfusion led to a strong activation of the JNK/SAPK (c-Jun NH2-terminal protein kinase/stress activated protein kinase), ERK (extracellular signal-regulated kinase), and p38 enzymes. These results with other previous studies suggest that the activation of JNK/SAPK in accordance with p38 contributes to the induction of apoptosis in CA1 neurons.

PACAP protects hippocampal neurons against apoptosis: involvement of JNK/SAPK signaling pathway

We have demonstrated that the ischemia-induced apoptosis of neurons in the CA1 region of the rat hippocampus was prevented by either intracerebroventricular or intravenous infusion of pituitary adenylate cyclase-activating polypeptide (PACAP). However, the molecular mechanisms underlying the anti-apoptotic effect of PACAP remain to be determined. Within 3-6 h after ischemia, the activities of members of the mitogen-activated protein (MAP) kinase family, including extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK)/stress-activated protein kinase (SAPK), and p38 were increased in the hippocampus. The ischemic stress had a potent influence on the MAP kinase family, especially on JNK/SAPK. PACAP inhibited the activation of JNK/SAPK after ischemic stress. Secretion of interleukin-6 (IL-6) into the cerebrospinal fluid was intensely stimulated after PACAP infusion. IL-6 inhibited the activation of JNK/SAPK, while it activated ERK. These observations suggest that PACAP and IL-6 act to inhibit the JNK/SAPK signaling pathway, thereby protecting neurons against apoptosis.