Establishment of medaka (Oryzias latipes) transgenic lines with the expression of green fluorescent protein fluorescence exclusively in germ cells: a useful model to monitor germ cells in a live vertebrate

We have generated transgenic medaka (teleost, Oryzias latipes), which allow us to monitor germ cells by green fluorescent protein (GFP) fluorescence in live specimens. Two medaka strains, himedaka (orange-red variety) and inbred QurtE, were used. The transgenic lines were achieved by microinjection of a construct containing the putative promoter region and 3' region of the medaka vasa gene (olvas). The intensity of GFP fluorescence increases dramatically in primordial germ cells (PGCs) located in the ventrolateral region of the posterior intestine around stage 25 (the onset of blood circulation). Whole-mount in situ hybridization and monitoring of ectopically located cells by GFP fluorescence suggested that (i) the increase in zygotic olvas expression occurs after PGC specification and (ii) PGCs can maintain their cell characteristics ectopically after stages 20-25. Around the day of hatching, the QurtE strain clearly exhibits sexual dimorphisms in the number of GFP fluorescent germ cells, a finding consistent with the appearance of leucophores, a sex-specific marker of QurtE. The GFP expression persists throughout the later stages in the mature ovary and testis. Thus, these transgenic medaka represent a live vertebrate model to investigate how germ cells migrate to form sexually dimorphic gonads, as well as a potential assay system for environmental substances that may affect gonad development. The use of a transgenic construct as a selective marker to efficiently isolate germ-line-transmitting founders during embryogenesis is also discussed.     

Prognosis After Brain Metastasis from Differentiated Thyroid Carcinoma

Background

In patients with differentiated thyroid carcinoma (DTC), lung and bone metastasis sometimes occur. However, brain metastasis (BM) is extremely rare. Because most previous reports about BM from DTC included a relatively small number of cases, the clinical characteristics and outcomes of BM are still unclear.

Patients and methods

Between 1965 and 2013, among 961 patients who had died because of DTC, 24 patients were diagnosed with BM from DTC. One patient with BM from DTC is still alive. To identify the prognostic factors for longer survival after BM, the medical records of these 25 patients were retrospectively reviewed.

Results

The median age at BM diagnosis was 66 years. Typical symptoms associated with BM had appeared in 20 patients (80 %). The Karnofsky Performance Status (KPS) was good (≥70) in 10 patients and poor (≤60) in 15 patients. Seven patients had a single intracranial lesion of BM, 6 patients had 2 or 3 lesions, and 9 patients had 4 or more. Eleven patients did not receive any treatment for BM, and 14 patients underwent surgical resection, radiation therapy, or both. One-year and 5-year disease-specific survival rates were 28 and 10.6 %, respectively. Good KPS (≥70), small number of intracranial lesions (≤3), and treatment for BM were prognostic factors for long survival on univariate analysis (p < 0.05). On multivariate analysis, only treatment for BM was significant.

Conclusion

Treatment of BM from DTC is indicated in patients who have a good KPS and fewer intracranial lesions, and some of them may achieve long survival.

     

Recent Insights into Clostridium perfringens Beta-Toxin

Clostridium perfringens beta-toxin is a key mediator of necrotizing enterocolitis and enterotoxemia. It is a pore-forming toxin (PFT) that exerts cytotoxic effect. Experimental investigation using piglet and rabbit intestinal loop models and a mouse infection model apparently showed that beta-toxin is the important pathogenic factor of the organisms. The toxin caused the swelling and disruption of HL-60 cells and formed a functional pore in the lipid raft microdomains of sensitive cells. These findings represent significant progress in the characterization of the toxin with knowledge on its biological features, mechanism of action and structure-function having been accumulated. Our aims here are to review the current progresses in our comprehension of the virulence of C. perfringens type C and the character, biological feature and structure-function of beta-toxin.     

Yohimbine-induced alterations of monoamine metabolism in the spontaneously hypertensive rat. I. The peripheral nervous system

The effects of alpha 2 adrenoreceptor blockade with YOH on blood pressure, plasma catecholamines and norepinephrine (NE) stores in kidney, adrenal and spleen of spontaneously hypertensive rats of the Okamoto strain (SHR) and Wistar-Kyoto (WKY) control animals were examined. YOH administration resulted in a significant (p less than 0.001) reduction in arterial pressure in both SHR and WKY. Plasma NE and EPI were significantly (p less than 0.05) elevated by YOH treatment in both SHR and WKY, but SHR exhibited a significantly (p less than 0.05) greater percent increase in plasma NE than WKY. YOH produced significant decreases in splenic NE content in both SHR and WKY but reduced renal NE content in the SHR only. SHR had significantly higher basal renal NE and DA content and fewer NE uptake (3H-desmethylimipramine binding) sites (p less than 0.05) than WKY. Treatment of SHR or WKY with either the alpha 2-adrenergic antagonist, idazoxan, or the alpha 1-antagonist, prazosin, failed to significantly alter renal NE levels from those found after saline injection. The enhanced YOH-induced renal NE depletion in SHR suggests an alteration in the presynaptic control of NE release in the genetically hypertensive rat, however, the effects of YOH in the SHR may be mediated by mechanisms unrelated to alpha 2-adrenergic receptors.     

基于物体空间序法的CT图像三维重建算法的研究

首先对三维可视化方法进行了分类概述。接着对基本的物体空间序法及其改进算法——抛雪球法做了详细的描述，并且通过对两组CT数据进行三维重建实验，得到高质量的重构图像。最后，本文研究并采用了提取表面体素进行体绘制加速的方法，实现了基于等值面提取表面的加速算法，实验证明加速算法能够满足显示要求并能起到明显的加速作用。     

Risk factors associated with having psoriatic arthritis in patients with cutaneous psoriasis

The aim of this study was to determine if the following characteristics were associated with the presence of psoriatic arthritis in a sample of psoriasis patients: race, family history of psoriasis and psoriatic arthritis, age of onset of psoriasis, smoking, alcohol consumption and the maximum body surface area (BSA) affected by psoriasis. This was a case–control study involving 400 psoriasis patients who attended the Psoriasis and Photo‐medicine clinic in the National Skin Center of Singapore over a 1‐year period. Cases were psoriasis patients with psoriatic arthritis while controls were psoriasis patients without psoriatic arthritis. The diagnosis of psoriatic arthritis was made by rheumatologists and participants completed a self‐administered standardized questionnaire. The maximum BSA involved was determined from the case notes. Psoriatic arthritis was not significantly associated with sex, race, age of onset of psoriasis, a family history of psoriasis, smoking and alcohol consumption but was significantly associated with a family history of psoriatic arthritis (P < 0.001) and the maximum body surface involved (P = 0.05). Using multivariate analysis to control for variables, the presence of psoriatic arthritis was significantly associated with a family history of psoriatic arthritis (odds ratio [OR] = 20.5; 95% confidence interval [CI] = 2.49–169.10) and the maximum BSA involved (OR = 2.52; 95% CI = 1.33–4.75). Indian psoriatic patients were more likely to have psoriatic arthritis compared to the other races. A family history of psoriatic arthritis and a greater maximum body surface involved may be associated with having psoriatic arthritis in this study population of psoriasis patients.     

From the Cover: Arginine ADP-ribosylation mechanism based on structural snapshots of iota-toxin and actin complex

Clostridium perfringens iota-toxin (Ia) mono-ADP ribosylates Arg177 of actin, leading to cytoskeletal disorganization and cell death. To fully understand the reaction mechanism of arginine-specific mono-ADP ribosyl transferase, the structure of the toxin-substrate protein complex must be characterized. Recently, we solved the crystal structure of Ia in complex with actin and the nonhydrolyzable NAD⁺ analog βTAD (thiazole-4-carboxamide adenine dinucleotide); however, the structures of the NAD⁺-bound form (NAD⁺-Ia-actin) and the ADP ribosylated form [Ia-ADP ribosylated (ADPR)-actin] remain unclear. Accidentally, we found that ethylene glycol as cryo-protectant inhibits ADP ribosylation and crystallized the NAD⁺-Ia-actin complex. Here we report high-resolution structures of NAD⁺-Ia-actin and Ia-ADPR-actin obtained by soaking apo-Ia-actin crystal with NAD⁺ under different conditions. The structures of NAD⁺-Ia-actin and Ia-ADPR-actin represent the pre- and postreaction states, respectively. By assigning the βTAD-Ia-actin structure to the transition state, the strain-alleviation model of ADP ribosylation, which we proposed previously, is experimentally confirmed and improved. Moreover, this reaction mechanism appears to be applicable not only to Ia but also to other ADP ribosyltransferases.     

Factors on delayed recovery of otitis media with effusion in children--clinical and bacteriological study

The resolution of middle ear effusions (MEE) of children with otitis media with effusion (OME) who underwent myringotomy for the bacteriological examination was analyzed in terms of the culture results and the clinical features. The present study consisted of 193 children (258 ears), and the MEE from 77 ears (30%) were culture positive and the respiratory pathogens were detected from 44 ears (17%). Each child was then assigned to receive either a more than two-week course of antibiotics, cefaclor (CCL) or not. At one month following entry, 53 (55%) out of 97 ears in CCL-treated group were effusion-free compared with 31 (40%) out of 78 ears in the control group (P less than 0.05). In the control group, the resolution of MEE was significantly poor in the recurrent cases and the cases with pathogen positive-MEE. The presence of accompanying diseases such as adenoid vegetation, chronic sinusitis and allergy, however, was not related to the resolution of MEE. On the other hand, the cure rate of the cases with pathogen positive-MEE and recurrent cases in the CCL-treated group showed significant improvement. Furthermore, the cases accompanying adenoid vegetation and chronic sinusitis tended to become effusion-free after the antibiotic treatment. Therefore, the persistent bacterial infection in the middle ear and/or surrounding organs such as adenoid plays possibly an important role in the delayed recovery of OME. Antibiotics treatment could increase, to some extent, the resolution of MEE in cases with OME.     

Clinical Response to Systemic Combined Chemotherapy with 5-Fluorouracil and Cisplatin (FP Therapy) in Patients with Advanced Pancreatic Cancer

Pancreatic cancer shows high mortality and has a poor prognosis.Although the rate of response to all chemotherapeutic regimensis low, some patients have shown improvement of their symptomsafter chemotherapy and/or radiotherapy without obvious tumorregression. We assessed the clinical benefit of systemic combinedchemotherapy with 5-fluorouracil and cisplatin (FP therapy)in 21 patients with advanced cancer of the pancreas. The clinicalresponse to FP therapy was evaluated using two parameters: pain(intensity of pain and consumption of morphine) and performancestatus. A patient was considered to be a clinical responderif one of two parameters was positive and the other was positiveor stable. Four patients (19%) responded. Two of the respondersachieved partial response according to the objective tumor response,and the remaining two showed no change. The survival periodin responders was significant longer than in the other patients.The clinical response may be one parameter for evaluating theresults of treatment for pancreatic cancer, and the longer survivalperiod of the clinical responders in this study supports thisnotion.