Endoplasmic reticulum stress and the unfolded protein response regulate genomic cystic fibrosis transmembrane conductance regulator expression

The unfolded protein response (UPR) is a cellular recovery mechanism activated by endoplasmic reticulum (ER) stress. The UPR is coordinated with the ER-associated degradation (ERAD) to regulate the protein load at the ER. In the present study, we tested how membrane protein biogenesis is regulated through the UPR in epithelia, using the cystic fibrosis transmembrane conductance regulator (CFTR) as a model. Pharmacological methods such as proteasome inhibition and treatment with brefeldin A and tunicamycin were used to induce ER stress and activate the UPR as monitored by increased levels of spliced XBP1 and BiP mRNA. The results indicate that activation of the UPR is followed by a significant decrease in genomic CFTR mRNA levels without significant changes in the mRNA levels of another membrane protein, the transferrin receptor. We also tested whether overexpression of a wild-type CFTR transgene in epithelia expressing endogenous wild-type CFTR activated the UPR. Although CFTR maturation is inefficient in this setting, the UPR was not activated. However, pharmacological induction of ER stress in these cells also led to decreased endogenous CFTR mRNA levels without affecting recombinant CFTR message levels. These results demonstrate that under ER stress conditions, endogenous CFTR biogenesis is regulated by the UPR through alterations in mRNA levels and posttranslationally by ERAD, whereas recombinant CFTR expression is regulated only by ERAD. endoplasmic reticulum-associated degradation; messenger ribonucleic acid     

Role of Type IV Pilins in Persistence of Vibrio vulnificus in Crassostrea virginica Oysters

Vibrio vulnificus is part of the natural estuarine microflora and accumulates in shellfish through filter feeding. It is responsible for the majority of seafood-associated fatalities in the United States mainly through consumption of raw oysters. Previously we have shown that a V. vulnificus mutant unable to express PilD, the type IV prepilin peptidase, does not express pili on the surface of the bacterium and is defective in adherence to human epithelial cells (R. N. Paranjpye, J. C. Lara, J. C. Pepe, C. M. Pepe, and M. S. Strom, Infect. Immun. 66:5659-5668, 1998). A mutant unable to express one of the type IV pilins, PilA, is also defective in adherence to epithelial cells as well as biofilm formation on abiotic surfaces (R. N. Paranjpye and M. S. Strom, Infect. Immun. 73:1411-1422, 2005). In this study we report that the loss of PilD or PilA significantly reduces the ability of V. vulnificus to persist in Crassostrea virginica over a 66-h interval, strongly suggesting that pili expressed by this bacterium play a role in colonization or persistence in oysters.     

Topical applications of iron chelators in photosensitization.

Generation of the reactive oxygen species (ROS) in skin by exposure to ultraviolet (UV) radiation induces a number of cutaneous pathologies such as skin cancer, photosensitization, and photoaging among others. Skin iron catalyzes UV generation of ROS. Topical application of iron chelators reduces erythema, epidermal and dermal hypertrophy, wrinkle formation, tumour appearance. It has been proposed that iron chelators can be useful agents against damaging effects of both short- and long-term UV exposure. A better understanding of the action mechanisms of iron chelators, might be useful to developing effective anticancer and antiphotoaging cosmetic products. Iron chelators may lead to accumulation of protoporphyrin IX (PpIX), a strong photosensitizer. The action of iron chelators in skin, related to PpIX increase has not yet been thoroughly studied. Therefore, we have investigated the formation of PpIX in normal mouse skin after topical application of creams containing metal chelators. The amount and distribution of porphyrins formed was determined by means of non-invasive fluorescence spectroscopy. Deferoxamine (DF), ethylenediaminetetraacetic acid (EDTA), 1,2-diethyl-3-hydroxypyridin-4-one (CP94), but not meso-2,3-dimercaptosuccinic acid (DMSA), caused increased accumulation of endogenous porphyrins in the skin. Fluorescence excitation and emission spectroscopy confirmed that PpIX was the main fluorescent species. The amount of PpIX accumulated in skin under the present conditions was not large enough to produce any significant erythema after light exposure. Further studies are needed to evaluate the role of PpIX induced by iron chelators used, against photoaging and cancer prevention.     

In vivo effects of adenosine A(2) receptor agonist and antagonist on neuronal and astrocytic intermediary metabolism studied with ex vivo (13)C MR spectroscopy.

The effect of adenosine A(2) receptor agonist 2-[p-(2-carboxyethyl)phenylethylamino]-5'-ethylcarboxamidoadenosine (CGS 21680) and antagonist 3,7-dimethyl-1-propargylxanthine (DMPX) on [1-(13)C]glucose and [1,2-(13)C]acetate metabolism was studied in rats by (13)C magnetic resonance (MR) spectroscopy and HPLC. In the cortex a significant reduction was observed in the amounts of [2-(13)C]GABA and [3-(13)C]aspartate from [1-(13)C]glucose in CGS 21680. In the subcortex the concentration of labelled [4-(13)C]glutamate was increased in both treatment groups. The amounts of [2 + 3-(13)C]succinate and [3-(13)C]lactate were increased in the CGS 21680 group compared to control, and the DMPX group showed an increase in the total amount of [6-(13)C]N-acetyl aspartate compared to control in the subcortex. Astrocyte metabolism was only affected in the cortex as shown by a decrease in the pyruvate carboxylase/pyruvate dehydrogenase ratio in glutamate and glutamine in the treatment groups. Labelling from [1,2-(13)C]acetate was not much affected by CGS 21680 or DMPX. However, the amount of [1,2-(13)C]acetate in cortex and subcortex was reduced in the DMPX group. In the cortex a reduction in the labelling of [3-(13)C]GABA in the DMPX group compared to control and an increase in the total amount of taurine in both treatment groups was detected. The present study shows that A(2) receptor agonist and antagonist have similar effects; however, in cortex GABAergic neurones and astrocytes were affected in contrast to subcortex, where glutamatergic neurones showed the greatest changes.     

Serum Collagen Type II Cleavage Epitope and Serum Hyaluronic Acid as Biomarkers for Treatment Monitoring of Dogs with Hip Osteoarthritis

The aim of this study was to evaluate the use of serum type II collagen cleavage epitope and serum hyaluronic acid as biomarkers for treatment monitoring in osteoarthritic dogs. For this purpose, a treatment model based on mesenchymal stem cells derived from adipose tissue combined with plasma rich in growth factors was used. This clinical study included 10 dogs with hip osteoarthritis. Both analytes were measured in serum at baseline, just before applying the treatment, and 1, 3, and 6 months after treatment. These results were compared with those obtained from force plate analysis using the same animals during the same study period. Levels of type II collagen cleavage epitope decreased and those of hyaluronic acid increased with clinical improvement objectively verified via force plate analysis, suggesting these two biomarkers could be effective as indicators of clinical development of joint disease in dogs.     

步林在青海柴达木盆地的早期工作记录——经典脊椎动物化石地点与现代地层框架的解译(英文)

1931 ～ 1932 年,博格·步林两次率领中瑞考察团( 又名斯文·赫定考察团) 到青海省柴达木盆地东部进行考察,在克鲁克湖与托素湖地区首次发现了丰富的新近纪哺乳动物化石。这批化石成为我国早期青藏高原古生物研究的奠基石。直至今日,双湖地区仍是青藏高原脊椎动物化石最丰富、研究程度最高的地区。柴达木盆地新近纪的堆积巨厚且连续,地层构造相对简单,盆地北缘地层出露好,是研究陆生哺乳动物演化的理想地点。然而,双湖地区地层的时代跨度超过 13 My,厚度接近 4600 m,如果化石层位不明,很容易引起动物群成分的混乱。步林对此似乎缺乏足够的认识,对所有采集的化石未做分层处理,导致后人对"柴达木动物群"年代的解释引起不少异议。步林并非对地层不重视。恰恰相反,他如同在甘肃塔奔布鲁克盆地的工作中那样,在缺乏地形图和地质资料的条件下做了大量的基础地层工作。他利用明显的地物( 山顶)和地质构造( 背斜) 作为参照系统,仔细地记录了化石的出露地点,并编制了一些草图。步林去世后,家属把他的野外记录留给赫定档案馆( Svan Hedin Archives) ,在斯德哥尔摩分几处收藏。遗憾的是,如同塔奔布鲁克盆地的情况,步林未能发表很多十分关键的化石地点资料,而发表的地质记录却被多数人忽略,所出版的游记也鲜为人知,个人档案记录更是深埋于历史的文献中。直到 1999 年,本文第一作者才首次接触到一些步林的野外原始资料。经过近 10 年多次对赫定档案馆的访问和对步林原始记录反复的野外核实,最终才将步林的经典地点结合进现代地层顺序的框架中。本文是继对步林塔奔布鲁克盆地燕丹图动物群经典地点与地层的研究后,进一步对其柴达木盆地化石地点的厘定与复原,是本系列文章之二。目的是将过去混淆于各地点的动物群逐一解译,将不同时代的化石分子置于现代地层与年代框架之中。幸运的是,步林的诸多野外记录都保存完好,结合发表的个人游记及地质记录,他所发表的多数哺乳动物化石都可以恢复到一定地层范围之内,尚能尽量减小经典化石地点的不确定性。本文试图整理步林未发表的珍贵资料,通过综合考证其他已发表的信息,结合作者在 1998 ～2010 年多次野外考察的结果,以期理顺柴达木地区经典化石点与现代地层框架的关系。这里将着重探讨经典化石点的生物地层学问题,并将步林柴达木盆地化石地点的野外记录资料译成英文附入文后,至于我们在柴达木盆地发现的其他化石点暂不涉及。步林主要在三个地区采集了化石: 托素湖北岸、怀头他拉村南及泉水梁火车站附近。尽管步林清楚地意识到其化石来自几千米厚的地层,但他统称其为柴达木动物群,成为以后混乱的主要原因。根据对柴达木新近纪的地层古生物考察,我们至少可以辨认出 4 个动物群: 中中新世欧龙布鲁克动物群、晚中新世早期托素动物群、深沟动物群和早上新世怀头他拉动物群。( 1) 中中新世欧龙布鲁克动物群。化石主要产于剖面底部克鲁克背斜两翼接近轴部的红色泥岩及绿色砂岩中。该动物群的成员发现较少,步林和我们都找到不多,主要来自两个地点: 怀头他拉剖面步林 165 号营地附近及泉水梁火车站东北 800 m 左右处。包括以下几个种类( 括号内为步林的化石编号; 该系列号码在步林的柴达木专著中广泛应用) : Olonbulukia tsaidamensis ( Nr. 356) ,Lagomeryx tsaidamensis ( Nr. 361) ,Stephanocemas( Nr. 368,407) ,? Dicroceros ( Nr. 372,397) ,? Eostyloceros ( Nr. 396,399,401) ,Acero-rhinus tsaidamensis ( Nr. 330,346,374,381) 。( 2) 晚中新世早期托素动物群。该动物群最初发现于托素湖北岸的狭长露头。步林对该点的记录最详细,其中各化石层位都被我们一一找到。托素湖的含哺乳动物化石层位局限在诺令根河( 连接克鲁克湖与托素湖之间的小河) 北岸 100 m 的地层中,是步林所有化石点中能最精确地确定层位的一个点( 即步林托素湖化石点都可以恢复到该段 100m 地层中) 。根据目前古地磁测量结果,该点 100 m 地层可以精确到 0. 3 Ma 范围之内。相当于含托素动物群层位的化石地点在怀头他拉剖面中也少量存在,但多数化石不特征,估计步林在此也找到不多。托素动物群最丰富的化石点在泉水梁车站东南的狭长露头。步林称做"一般条带"( "General Strips") 。在厚度不到250 m,北西-南东方向延伸达8 km的地层中,化石均匀散布、保存完好,是柴达木目前最丰富的化石点。托素动物群包括以下种类( 括号内为步林的化石编号) : "Ictitherium sp. "( Nr. 542) ,Tsaidamotherium hedini( Nr. 447,457) ,Tossunnoria pseudibex ( Nr. 449,481,537) ,Qurliqnoria cheni ( Nr. 441) ,Qurliqnoria sp. ( Nr. 508) ,Olonbulukia tsaidamensis ( Nr. 429) ,Chalicotheriidae indet.( Nr. 317) ,Hipparion sp. ( Nr. 352,444,467,493,498,500,501,523,553) ,Acerorhi-nus tsaidamensis ( Nr. 418,430,438,456,459,488,502-4,511,516,525-7,536,538,555-6) ,? Tetralophodon ( Nr. 458,487,524,530,534) ,Giraffidae indet. ( Nr. 316,320) ,? Eostyloceros ( Nr. 334,349) 。另外我们在泉水梁地点也找到大量化石,研究后可望增加更多的成员。泉水梁是我国少数几个三趾马出现最早的地点之一。该剖面目前还没有古地磁资料,但通过与怀头他拉古地磁剖面的对比,泉水梁三趾马出现的最低层位应大致在 C5r. 1r反向带与 C5r. 1n 正向带之间( 约 11. 12 Ma) 。另外托素动物群所代表的时代,是青藏高原首次出现独特种类的时代。牛羊科中具有高原特色的种类包括 Tsaidamotherium hedini,Tossunnoria pseudibex,Qurliqnoria cheni 和 Olonbulukia tsaidamensis,其中 Qurliqnoria cheni可能是现代藏羚羊( Pantholops) 的祖先类型。( 3) 晚中新世早期深沟动物群。深沟动物群是根据德令哈南部深沟剖面的化石建立的。产该动物群的地层虽然在怀头他拉剖面中段出露,但目前还没找到特征的化石。步林的个别不确定的化石有可能属于深沟动物群。邱铸鼎和李强最近( 2008) 对深沟的小哺乳动物做了详细的描述,认为与陕西蓝田霸河组下部的小哺乳动物组合最接近。( 4) 早上新世怀头他拉动物群。怀头他拉动物群也处于怀头他拉剖面上部化石不丰富的地段。从步林的野外记录中,惟一能够比较确定的化石是一些驼鸟蛋片。我们也仅增加了几种小哺乳动物( 未研) 。     

Association between tumor characteristics and second primary cancers with cutaneous melanoma survival: A nationwide cohort study

The increased survival in malignant cutaneous melanoma (melanoma) is probably due to early diagnosis combined with improved treatment most recently. National health campaigns and screening programs for melanoma detection were started in Sweden several decades ago. We want to assess the influence of tumor characteristics, based on the TNM classification, and of second primary cancers on overall survival in melanoma. We used the Swedish Cancer Registry to assess all‐cause survival in melanoma from 2003 to 2015. Hazard ratios (HRs) were estimated using multivariable Cox regression models. A total of 19,773 melanoma patients were diagnosed with TNM data. Survival showed a strong improving trend over time (p‐trend <.001). T1a was the most common classification (48.0% of all), while higher T class was associated systematically with worse survival (p‐trend <.001). For distant metastases, the HR was 3.17, accounting for 0.9% of the patients. Any types of second primary cancers, other than melanoma, were associated with an HR of 2.00, accounted for 6.7% of all cases. Even if melanoma survival in Sweden ranks among the best national rates, the large percentage of patients with advanced tumors (T3b, T4a, and T4b, 17%) and 21% of deaths with T1a call for improved preventive and follow‐up strategies.     

Migration and isolation during the turbulent Ponto‐Caspian Pleistocene create high diversity in the crustacean Paramysis lacustris

The Ponto‐Caspian brackish‐water fauna inhabits estuaries and rivers of the Black, Azov and Caspian seas and is fragmented by higher salinity waters and a major interbasin watershed. The fauna is known for the high levels of endemism, complex zoogeographic histories, and as a recent source of successful invasive species. It remains debated whether the Black and Azov Sea brackish‐water populations survived unfavourable Pleistocene conditions in multiple separate refugia or whether the two seas were (repeatedly) recolonized from the Caspian. Using microsatellite and mtDNA markers, we demonstrate deep among‐ and within‐basin subdivisions in a widespread Ponto‐Caspian mysid crustacean Paramysis lacustris. Five genetic clusters were identified, but their relationships did not reflect the geography of the region. The Azov cluster was the most distinct (4–5% COI divergence), despite its geographic position in the corridor between Black and Caspian seas, and may represent a new species. In the northern Black Sea area, the Dnieper cluster was closer to the Caspian cluster than to the neighbouring Danube–Dniester–Bug populations, suggesting separate colonizations of the Black Sea. Overall, the data implied a predominant gene flow from the east to the Black Sea and highlight the importance of Caspian Sea transgressions in facilitating dispersal. Yet, the presence of distinct lineages in the Black Sea points to the persistence of isolated refugial populations that have gained diagnostic differences under presumably high mutation rates and large population sizes. The unfavourable Pleistocene periods in the Black Sea therefore appear to have promoted diversification of the brackish‐water lineages, rather than extirpated them.