Cumulus cells secrete a meiosi-inducing substance by stimulation with forskolin and dibutyric cyclic adenosine monophosphate

The role of the cumulus cells in initiating the resumption of meiosis after exposure to forskolin and dbcAMP was studied in the mouse. The resumption of meiosis was monitored by the percentage of germinal vesicle breakdown (GVBD) and polar body formation (PB). The cumulus-enclosed oocytes (CEO) and denuded oocytes (DO) were cultured with and without hypoxanthine (HX) in the culture medium. Three types of experiments were performed: (1) Effect of forskolin on spontaneous resumption of meiosis, i.e. cultures without HX, and two experiments in which HX is present throughout the culture: (2) Effect of transient exposure to forskolin or dibutyric-cyclic adenosinemonophosphate (dbcAMP) on GVBD prior to continued culture without forskolin or dbcAMP (oocyte priming). (3) Priming of CEO with forskolin for 2 hr, separation of cumulus cells and oocytes, followed by coculture of rejoined cumulus cells and oocytes, or coculture of the cumulus cells and new, unprimed DO. (1) Forskolin inhibited a spontaneous resumption of meiosis in a dose-dependent manner during the first 5 hr of culturing. After 22 hr all controls and CEO resumed meiosis, whereas only half of the DO did. (2) At least 1 hr of priming the CEO with forskolin is needed to induce GVBD and PB formation, but forskolin inhibited the resumption of meiosis when present for 24 hr. Similar results were obtained with a high concentration of dbcAMP. (3) A separation and rejoining of oocytes and cumulus cells after priming induced the resumption of meiosis in a significantly greater number of oocytes than in the control oocytes which were not primed. The GVBD of unstimulated DO also increased significantly when cocultured with cumulus cells from primed CEO. The percentage of GVBD in unprimed DO and in DO isolated from primed CEO was the same. We suggest that within 1–2 hr, forskolin and cAMP stimulate cumulus cells to produce a diffusible meiosis-inducing substance which overcomes HX-inhibition and induces oocyte maturation, including both GVBD and PB formation. The CEO must be primed for more than 2 hr before the resumption of meiosis in DO isolated from such CEO is induced. Oocyte-cumulus connections are crucial as far as initiating the production of a meiosis-inducing substance is concerned. Oocyte-cumulus connections are not needed for transferring this substance to the oocyte. © 1994 Wiley-Liss, Inc.     

Nutrient utilization during bioreactor culture,and maturation of somatic embryo cultures ofPicea mariana andPicea glauca-engelmannii

Summary Embryogenic cell cultures ofPicea mariana (black spruce) and the species complexPicea glauca-engelmannii (interior spruce) were maintained either as suspensions in liquid medium in 250 or 500-ml-capacity shake-flasks, 7-liter-capacity airlift or mechanically stirred bioreactors, or on agar-solidified medium. Cultures from each of the maintenance conditions were subsequently transferred to agar-solidified LP medium containing 40μM (±) -abscisic acid for maturation into cotyledonary stage embryos. For both species, the highest maturation frequency resulted from cultures grown in the airlift bioreactor. With black spruce cells grown in the airlift bioreactor containing LP medium with 60 mM sucrose, a maximum of 7.1 g·liter⁻¹ dry weight and 2892 embryos·ml⁻¹ were obtained after 15 days. For interior spruce cells, a maximum dry weight of 5.9 g·liter⁻¹ and 2698 embryos·ml⁻¹ were obtained after 21 to 30 days. During culture over 2 wk, ammonia was almost completely utilized by both species, wherease nitrate was depleted to 40% of the initial concentration. Sucrose was rapidly hydrolyzed to glucose and fructose by both species. Black spruce cultures preferentially metabolized glucose, whereas interior spruce preferentially metabolized fructose. Improved growth of interior spruce cells in mechanically stirred bioreactors occurred when cultured in LP medium with 60 mM fructose as the sole carbon source. NRCC no. 36479     

Microhabitat use by marsh-edge fishes in a Louisiana estuary

Synopsis We used a drop sampler to characterize use of the marsh-edge ecotone by small fishes along two transects running inland from the Gulf of Mexico for ca. 25 km in Louisiana's Barataria-Caminada Bay System. Monthly sampling was stratified among upper, middle, and lower reaches and within reaches to characterize fish responses to salinity, depth, distance from shore, substrate, dissolved oxygen concentration, temperature, turbidity, velocity, and emergent stem density. In 681 quantitative samples, covering 658 m², collected between October 1987 and October 1989, we collected 57 fish species and 16 864 individuals, primarily larvae and juveniles. The 15 most abundant fishes, comprising 97.7% of all individuals, were concentrated near the marsh edge (i.e., 0 to 1.25 m distance). Some significant differences within species for seasonal variables (e.g., temperature and dissolved oxygen concentration) reflected the ephemeral duration of early life history stages. Other differences reflected ontogenetic microhabitat shifts (e.g., depth and distance from shore). Within ecological groups, characterized as demersal residents, nektonic transients, and demersal transients, spatial and temporal segregation reflected the particular habitat requirements of each species. In a principal component analysis of microhabitat use, the first three components were interpreted as seasonal, depth-and-distance, and salinity axes, respectively. The array of species and size classes in principal component space reflected the complex dimensionality of microhabitat use. The high density of fish larvae and juveniles near the marsh edge confirmed the importance of the marsh-edge ecotone as a nursery for many estuarine-dependent fishes.     

浙西早寒武世梅树村期棒状化石

该文记述了浙江省西部江山县新塘坞地区灯影组(梅树村期)中新发现的矿化骨骼化石——浙江棒(新属)Zhejiangorhabdion gen.nov.。该化石的形态与以往化石类群均不相同,为个体微小的棒状,表面具较复杂的纹饰,不同个体间的纹饰都有一定变化,推测是动物体内不同部位的骨棒所具有的特征,代表了一个新的化石类群。新属的发现丰富了梅树村期动物群的内容,对了解具骨骼动物群体在这一时期的演化具有一定的意义。     

Palynological and palaeobotanical investigations in the area of the post-medieval Helsinki Old Town

Pollen, phytolith, and plant macrofossil analyses were carried out on the cultural layers of Helsinki Old Town excavated by the Helsinki City Museum and dated to the 15–17th centuries. Cultural mineral soil layers, a former ditch, a well, one waste pit, one waste heap and three house areas were investigated. The results show that-within certain limits-pollen in the mineral soil reflects the cultural changes of the local settlement from rural to urban. Among the main anthropogenic indicators, the high NAP (non-arboreal pollen) frequencies, the low pollen concentration values, and especially the high frequencies of Cichoriaceae (Liguliflorae) pollen should be emphasized. The macrofossil data were used to determine the species list of the herb pollen and to make a more detailed reconstruction of the local vegetation at Helsinki Old Town.     

鼠兔核质杂交胚胎早期发育的研究

细胞核移植技术已被证明是研究发育中核质相互关系的非常重要的手段之一,电融合技术也是近十年发展起来的新型细胞融合技术。本实验运用这两项技术,进行了鼠、兔目间核质杂交实验,小鼠8-细胞核在激活的兔去核卵母细胞中,发生了染色体超前凝聚及核膨胀,融合卵移植到小鼠输卵管4.5天后,冲洗出,有5.4%的重构卵发育到囊胚期,通过染色体检查,囊胚细胞中均为小鼠染色体,其中一个囊胚为正常小鼠核型(2 n=40,XX)。通过本实验,我们认为:鼠兔远缘核质杂交胚胎的早期发育是可能的。     

针刺运动疗法联合早期康复训练对急性踝关节扭伤患者踝关节功能、血清炎症因子和致痛物质水平的影响

摘要 目的：观察针刺运动疗法联合早期康复训练对急性踝关节扭伤患者踝关节功能、血清炎症因子和致痛物质水平的影响。方法：选取湖南中医药大学第一附属医院2019年5月~2022年1月期间收治的116例急性踝关节扭伤患者。按照随机数字表法分为对照组（早期康复训练,n=58）和研究组（针刺运动疗法联合早期康复训练,n=58）。观察两组治疗前、治疗4周后的疗效、量表评分[视觉模拟评分（VAS）、美国足与踝关节协会（AOFAS）踝-后足功能评分]、踝关节功能、血清炎症因子[白细胞介素（IL）-1β、IL-6和肿瘤坏死因子-α（TNF-α）]和致痛物质[神经肽（NPY）、P物质（SP）]水平。结果：研究组的临床总有效率为96.55%,高于对照组的77.59%,差异有统计学意义（P<0.05）。治疗4周后,研究组的AOFAS评分高于对照组（P<0.05）,VAS评分低于对照组（P<0.05）,血清IL-6、TNF-α、IL-1β水平低于对照组（P<0.05）,踝关节背伸活动度、踝关节跖屈活动度大于对照组（P<0.05）,血清NPY、SP水平低于对照组（P<0.05）。结论：急性踝关节扭伤患者经针刺运动疗法联合早期康复训练干预后,可有效降低其血清致痛物质和炎症因子水平,有利于疼痛症状的缓解及踝关节功能的恢复。     

关节镜下双排缝合桥固定与单排固定治疗肩袖全层撕裂的疗效对比及术后早期再撕裂的危险因素分析

摘要 目的：对比关节镜下双排缝合桥固定和单排固定治疗肩袖全层撕裂的疗效,并分析术后早期再撕裂的危险因素。方法：回顾性分析广州中医药大学附属北碚中医院2018年1月~2021年12月期间收治的200例肩袖全层撕裂患者的临床资料,根据手术方案的不同分为A组（n=97,接受单排固定治疗）和B组（n=103,接受双排缝合桥固定治疗）。对比两组的疼痛、肩关节功能情况、肩关节活动度及术后早期再撕裂发生率。采用单因素和多因素Logistic回归分析肩袖全层撕裂患者术后早期再撕裂的危险因素。结果：术后6个月,B组视觉疼痛模拟评分量表（VAS）评分低于A组,美国加州大学肩关节评分系统（UCLA）评分、美国肩肘外科医师学会（ASES）评分高于A组（P<0.05）。术后6个月,B组前屈、外展、体侧外旋角度大于A组（P<0.05）。B组的术后早期再撕裂总发生率低于A组（P<0.05）。术后早期再撕裂的发生与糖尿病史、撕裂大小、吸烟史、年龄、术前肌肉质量、性别、脂肪浸润、注射皮质类固醇有关（P<0.05）。多因素Logistic回归分析结果显示：年龄≥60岁、性别为男性、吸烟史、糖尿病史、撕裂大小为巨大型再撕裂、脂肪浸润、注射皮质类固醇是术后早期再撕裂发生的危险因素（P<0.05）。结论：关节镜下双排缝合桥固定治疗肩袖全层撕裂,可更好的减轻疼痛症状,改善关节功能和关节活动度。此外,糖尿病史、脂肪浸润、吸烟史、高龄、撕裂大小为巨大型再撕裂、男性、注射皮质类固醇等是肩袖全层撕裂患者术后早期再撕裂的危险因素。     

The Early Silurian brachiopod Eocoelia from the Hudson Bay Basin, Canada

Eocoelia akimiskii sp. nov. from the Lower Silurian (upper Telychian) Attawapiskat Formation of Akimiski Island, James Bay, Nunavut, is the first and oldest Eocoelia to be described from the Hudson Bay Basin, one of three largest inland basins of North America. The new species lacks dental plates, dental cavities, and marginal deflection or lip, which indicates a post-Aeronian form of the well-known Eocoelia lineage. In rib numbers, Eocoelia akimiskii falls between E. curtisi and E. sulcata , being closer to E. sulcata . In rib strength, however, the new species is more closely allied to E. curtisi . Although Eocoelia is currently assigned to the Rhynchonellida because of its lack of spiralia, several features (particularly the lack of a septalium, the presence of a unique notothyrial platform and cardinal process, and dense, free-hanging fibrous growth frills) of the genus and other leptocoeliids are distinctly atypical of the rhynchonellides. The new species occurs in an inter-reef, shelly packstone facies within the Attawapiskat Formation, which is characterized by coral-stromatoporoid reefs with abundant, diverse, reef-dwelling brachiopods and other shelly organisms. The close association of Eocoelia akimiskii with the Attawapiskat reefs supports a shallow subtidal (BA2) setting generally assigned to the Eocoelia Community. The reefs themselves, however, host an extremely abundant brachiopod fauna dominated by Pentameroides , Trimerella , Septatrypa , and Gypidula . Four species of Clorinda are also common elements of the reef-dwelling brachiopods. This demonstrates that the concept of the classic Early Silurian level-bottom brachiopod communities cannot be directly applied to reef-dwelling brachiopod communities.