Dose- and time-dependent responses for micronucleus induction by X-rays and fast neutrons in gill cells of medaka (Oryzias latipes)

Medaka fish (Oryzias latipes) were exposed to various doses of X-rays or fast neutrons, and the frequency of micronucleated cells (MNCs) was measured in gills sampled at 12- or 24-hr intervals from 12 to 96 hr after exposure. The resulting time course of MNC frequency was biphasic, with a clear peak 24 hr after exposure, irrespective of the kind of radiation applied and the dose used. The half-life of MNCs induced in the gill tissues by the two exposures fluctuated around 28 hr, with no significant dose-dependent trend for either X-ray- or neutron-exposed fish. As assayed 24 hr after exposure, the MNC frequency increased linearly over the control level with increasing doses of both X-rays and fast neutrons. The relative biological effectiveness (RBE) of fast neutrons to X-rays for MNC induction was estimated to be 4.3 +/- 0.6. This value is close to the RBE value of 5.1 +/- 0.3 reported for fast neutron induction of somatic crossing-over mutations in Drosophila melanogaster that arise from recombination repair of DNA double-strand breaks. These results and other data support our conclusion that the medaka gill cell micronucleus assay is a reliable short-term test for detecting potential inducers of DNA double-strand breaks.     

Use of the genomic subtractive hybridization technique to develop a real-time PCR assay for quantitative detection of Prevotella spp. in oral biofilm samples

Genomic subtractive hybridization was used to design Prevotella nigrescens-specific primers and TaqMan probes. Based on this technique, a TaqMan real-time PCR assay was developed for quantifying four oral black-pigmented Prevotella species. The combination of real-time PCR and genomic subtractive hybridization is useful for preparing species-specific primer-probe sets for closely related species.     

Gene therapy for renal anemia in mice with polycystic kidney using an adenovirus vector encoding the human erythropoietin gene

BACKGROUND: Recombinant human erythropoietin (rHuEPO) is primarily used for patients with anemia associated with end-stage renal disease. We evaluated the efficacy of EPO gene therapy using adenovirus vector for chronic renal failure mice expressing severe renal anemia. METHODS: Recombinant HuEPO gene transfer to mesothelial cells was performed in vitro and in vivo. Recombinant replication-deficient adenoviruses containing rHuEPO cDNA (AdCMVEPO), E. coli lacZ gene (AdCMVlacZ), or an nonexogenous gene (AdNull as control vector) driven by the cytomegalovirus promotor/enhancer were constructed. The oligosaccharides associated with the rHuEPO from AdCMVEPO-treated mesothelial cells were analyzed. For in vivo study, the DBA/2FG-pcy mouse, a model for human autosomal recessive polycystic kidney disease resulting in chronic renal failure with progressive anemia, was used. RESULTS: The sialylated oligosaccharides associated with the rHuEPO produced in AdCMVEPO-treated mesothelial cells occupied 78 +/- 0.7% of the total oligosaccharide pool. A single intraperitoneal administration of AdCMVEPO induced rHuEPO synthesis in the peritoneal cells and a marked increase in erythrocyte production. The maximal increase in hematocrit (43 +/- 4%) was observed on day 28, and it remained elevated for 40 days. CONCLUSION: These results indicate that intraperitoneal administration of AdCMVEPO improves renal anemia in mice with chronic renal failure and that the mesothelial cell is an appropriate target cell for gene transfer.     

Contrasts in gait mechanics of individuals with proximal femoral focal deficiency: Syme amputation versus Van Nes rotational osteotomy

Lower-limb kinematics and kinetics during preferred and fast speeds of walking were measured in persons with proximal femoral focal deficiency to compare outcomes after Syme amputation (nine subjects) with those after Van Nes rotational osteotomy (10 subjects). Subjects with a Van Nes rotational osteotomy and full tibial rotation (seven subjects) demonstrated prosthetic knee function during stance as they were able to support a flexed-knee posture at both speeds and produced greater knee-extensor moments at preferred speeds as compared with the Syme group (p < 0.05). Nonprosthetic limb compensatory mechanics were significantly exacerbated in subjects with a Syme amputation compared with the Van Nes group: (a) stance-phase vaulting, resulting in greater inappropriate ankle-power generation at both walking speeds, (b) excessive hip-extensor moments at fast speeds, (c) excessive hip-power absorption and generation at both speeds, and (d) excessive knee-joint power generation at both speeds (p < 0.05). The improved gait after Van Nes rotational osteotomy is one factor that should be considered when making clinical decisions for children with proximal femoral focal deficiency.     

A case of pulmonary type of ovarian small cell carcinoma

Small cell carcinoma is a rare form of ovarian cancer with a poor prognosis. It is divided into two types, the hypercalcemic and the pulmonary type, of which the latter is extremely rare. A 49-year-old woman presented with an acute abdomen and was suspected to have torsion of a left ovarian tumor, which was followed up with an emergency operation. Postoperative pathological examination gave a diagnosis of the pulmonary type of ovarian small cell carcinoma. Six courses of paclitaxel and carboplatin therapy were given as adjuvant chemotherapy. The patient has survived for 36 months without recurrence. Here we present an extremely rare patient with the pulmonary type of ovarian small cell carcinoma.     

Persistent subclinical rejection associated with nodular B-cell infiltrates in a renal transplant recipient

Abstract:  Recently, B-cell infiltrates in acute rejection grafts have attracted interest as an indicator of refractory rejection. Here, we report a case of deceased donor renal transplantation in a Japanese recipient operated overseas in which the recipient suffered from persistent tubulointerstitial rejection episodes associated with B-cell infiltrates. A 59-yr-old man with end-stage renal disease caused by immunoglobulin A nephropathy underwent deceased donor renal transplantation overseas in December 2005. The initial post-operative course was uneventful. The patient was referred to our hospital one month after transplantation. He maintained stable renal function throughout the follow-up period. The maintenance immunosuppressive regimen consisted of tacrolimus, mycophenolate mofetil and methylprednisolone. His serum creatinine concentration remained around 1.0 mg/dL, with no evidence of proteinuria. However, a discrepancy was detected between the renal function and the pathological findings. The pathology showed subclinical tubulointerstitial rejection with nodular B-cell infiltrates refractory to aggressive antirejection therapy. A steroid pulse and 15-deoxyspergualin were ineffective and the patient developed interstitial fibrosis and tubular atrophy by one yr after the transplantation, with persistent tubulitis and B-cell infiltrates. We treated the refractory rejection with B-cell infiltrates with a single 200 mg/body dose of rituximab and obtained an improvement. The pathological findings after administering rituximab consisted of mild tubulitis classified as Banff borderline, and elimination of the nodular B-cell infiltrates. At present, 20 months after renal transplantation, the patient continues to maintain stable renal function, with a good serum creatinine concentration (0.87 mg/dL).     

Holmium laser enucleation of the prostate versus transurethral resection of the prostate: a randomized clinical trial

Objective

To evaluate the efficacy and safety of holmium laser enucleation of the prostate (HoLEP) and transurethral resection of the prostate (TURP), for treatment of benign prostatic hyperplasia (BPH).

Methods

A total of 164 cases of BPH were selected from patients who were hospitalized between January 2010 and December 2011. Patients had received either HoLEP or TURP treatment. Clinical data were collected from the perioperative period, 1 month after surgery, and 12 months after surgery.

Results

There was no significant difference between the two groups in the maximum urinary flow rate (Q _max), postvoid residual volume (PVR), international prostate symptom score (IPSS), or quality-of-life score (QOL score) at 1 month after surgery (p = 0.56, p = 0.346, p = 0.536 and p = 0.145, respectively). However, after 12 months, patients from the HoLEP group demonstrated better scores in Q _max, PVR, IPSS, and QOL than those from the TURP group (p = 0.037, p = 0.003, p < 0.001 and p = 0.019, respectively). The two groups had comparable operation time (p = 0.105), catheterization time (p = 0.173), and length of hospital stay (p = 0.395), but were statistically different in the weight of resected prostate tissue (p < 0.001), bladder irrigation time (p < 0.001), hemoglobin levels (p = 0.011), and blood sodium levels (p = 0.002) after surgery.

Conclusions

Compared to TURP, HoLEP was safer and had better long-term efficacy as assessed by multiple quantitative measures. Therefore, HoLEP may present a better option in the treatment of BPH.     

线上线下混合式教学在医学院校高等数学教学中的实践研究

目的 为解决医学院校学生高等数学学习难度大、学时紧、学生学习兴趣差、接受程度低等困扰高等数学学习的问题,积极开展线上线下混合式教学模式。方法 选取2022级临床医学专业、生物医学工程专业、信息管理与信息系统专业共6个班级243名学生作为研究对象（试验组）,采用自制线上学习资源与中国大学MOOC教学资源结合的线上线下混合式教学模式。课前根据教学内容设置教学目标、上传教学资源,利用超星学习通平台发布课前学习任务,帮助学生课前预习。课中教师面授,并在学习通平台发布课堂提问、随堂测验等,检验课上学习效果,方便教师掌握学生学习情况,及时进行教学调整,帮助学生顺利完成课上学习。课后在超星学习通平台上发布课上授课视频及课后习题讲解等,辅助学生巩固课上学习。并分班建立课程QQ群,方便课后与学生沟通、辅导答疑。采用SPSS 20.0软件进行t检验。结果 线上线下混合式教学有效提高了学生课上的参与度,极大地调动了学生的学习热情,课上平均师生互动由每节6次提高到10次;课上出勤率由原来的93.93%（232/247）提高到97.94%（238/243）;作业按时提交率由原来的92.71%（229/247）提高到96.71%（235/243）。课程教学完成以后,学生的期末综合成绩由（81.27±4.56）分提高到（89.52±3.42）,差异有统计学意义（t=8.25,P<0.001）。结论 线上线下混合式教学的采用,不仅对学生学习成绩有良性作用,而且更大程度地激发了学生学习高等数学的热情。后续期待学生应用数学解决实际问题的能力进一步提高。