The mouse Dlx-2 (Tes-1) gene is expressed in spatially restricted domains of the forebrain, face and limbs in midgestation mouse embryos

The pattern of RNA expression of the murine Dlx-2 (Tes-1) homeobox gene is described in embryos ranging in age from E8.5 through E11.5. Dlx-2 is a vertebrate homologue of the Drosophila Distal-less (Dll) gene. Dll expression in the Drosophila embryo is principally limited to the primordia of the brain, head and limbs. Dlx-2 is also expressed principally in the primordia of the forebrain, head and limbs. Within these regions it is expressed in spatially restricted domains. These include two discontinuous regions of the forebrain (basal telencephalon and ventral diencephalon), the branchial arches, facial ectoderm, cranial ganglia and limb ectoderm. Several mouse and human disorders have phenotypes which potentially are the result of mutations in the Dlx genes.     

直接前方入路与后外侧入路全髋关节置换治疗股骨颈骨折的疗效比较及术后髋关节功能的影响因素分析

摘要 目的：比较直接前方入路与后外侧入路全髋关节置换治疗股骨颈骨折的疗效及术后髋关节功能的影响因素分析。方法：选取2019年5月至2021年12月徐州医科大学附属医院收治并行全髋关节置换治疗股骨颈骨折患者96例,按照手术方法的不同分为直接前方入路组（n=48）和后外侧入路组（n=48）。观察两组围术期指标、并发症发生情况,比较两组治疗前后Harris评分、视觉模拟评分法（VAS）。并应用单因素、多因素Logistic回归分析患者术后髋关节功能的影响因素。结果：直接前方入路组下床时间、切口长度、住院时间显著短于后外侧入路组,术中失血量、术后引流量显著低于后外侧入路组,而手术时间显著长于后外侧入路组（P<0.05）。直接前方入路组术后1、3个月Harris评分显著高于后外侧入路组,VAS评分显著低于后外侧入路组（P<0.05）。两组术后并发症发生率比较,无统计学差异（P＞0.05）。两组治疗6个月后髋关节功能优良率比较,差异无统计学意义（P>0.05）。多因素Logistic回归分析结果显示：体质量指数≥24 kg/m²、术后锻炼时间<3 h/d、合并骨质疏松是接受全髋关节置换治疗的股骨颈骨折患者术后髋关节功能不良的危险因素（P＜0.05）。结论：直接前方入路全髋关节置换术较后外侧入路全髋关节置换术短期内优势明显,表现为对患者的创伤更小,术后疼痛程度较轻,有利于患者的髋关节功能恢复。体质量指数≥24 kg/m²、术后锻炼时间<3 h/d、合并骨质疏松是接受全髋关节置换治疗的股骨颈骨折患者术后髋关节功能不良的危险因素。     

丹参素注射液对急性心肌梗死大鼠的心室重构、心室功能及肢体导联与胸导联心电图参数的影响

摘要 目的：探讨丹参素注射液对急性心肌梗死大鼠的心室重构、心室功能及肢体导联与胸导联心电图参数的影响。方法：选择SD大鼠40只,将其鼠随机模型组、假手术组、硝酸甘油组、丹参注射液组。假手术组大鼠给予只在冠状动脉处穿针,不进行结扎,其余步骤同其余3组,其余3组均进行动物模型构建。假手术组、模型组大鼠均腹腔注射氯化钠注射液,硝酸甘油组腹腔注射硝酸甘油,丹参注射液组腹腔注射丹参注射液。对比4组大鼠的肢体导联与胸导联心电图参数,对比4组大鼠的血液流变学指标、左心室功能及左心室重构。结果：模型组的Ⅰ、Ⅱ、Ⅲ、aVL、aVF、V1、V2、V5、血浆粘度、纤维蛋白原、红细胞聚集指数、舒张末期室间隔厚度、左室舒张末期内径、左室收缩末期内径、左室舒张末期容积、左室收缩末期容积明显较假手术组、硝酸甘油组、丹参注射液组高,硝酸甘油、丹参注射液组以上指标明显较假手术组高,模型组的的左室舒张末期厚度、左室射血分数、左室短轴缩短率明显较假手术组、硝酸甘油组、丹参注射液组低,硝酸甘油、丹参注射液组的左室舒张末期厚度、左室射血分数、左室短轴缩短率明显较假手术组低。模型组的左心室重量指数、左心室截面直径明显较假手术组、硝酸甘油组、丹参注射液组高,硝酸甘油、丹参注射液组的左心室重量指数、左心室截面直径、梗死面积明显较假手术组高（P<0.05）,硝酸甘油组与丹参注射液组以上指标对比无差异（P>0.05）。结论：丹参素注射液可改善急性心肌梗死大鼠的心室重构、左心室功能及肢体导联与胸导联心电图参数,可能与其可降低大鼠的血液流变学指标水平有关。     

Planar cell polarity regulators in asymmetric organogenesis during development and disease

The phenomenon of planar cell polarity is critically required for a myriad of morphogenetic processes in metazoan and is accurately controlled by several conserved modules. Six “core” proteins, including Frizzled, Flamingo (Celsr), Van Gogh (Vangl), Dishevelled, Prickle, and Diego (Ankrd6), are major components of the Wnt/planar cell polarity pathway. The Fat/Dchs protocadherins and the Scrib polarity complex also function to instruct cellular polarization. In vertebrates, all these pathways are essential for tissue and organ morphogenesis, such as neural tube closure, left–right symmetry breaking, heart and gut morphogenesis, lung and kidney branching, stereociliary bundle orientation, and proximal–distal limb elongation. Mutations in planar polarity genes are closely linked to various congenital diseases. Striking advances have been made in deciphering their contribution to the establishment of spatially oriented pattern in developing organs and the maintenance of tissue homeostasis. The challenge remains to clarify the complex interplay of different polarity pathways in organogenesis and the link of cell polarity to cell fate specification. Interdisciplinary approaches are also important to understand the roles of mechanical forces in coupling cellular polarization and differentiation. This review outlines current advances on planar polarity regulators in asymmetric organ formation, with the aim to identify questions that deserve further investigation.     

Body weight: its relation to tissue composition, segment distribution, and motor function. I. Interspecific comparisons.

The composition of skin, muscle, and bone and their distribution throughout the body are compared for "advanced" or "specialized" species (Alouatta, Macaca, Canis, Felis, Lepus); smaller, more closely related species (Tupaia and the Lorisidae); and several species within the same ecosystem (Barro Colorado Island, Panama). Among the most significant variables, the skin of sloths, howlers and macaques constitutes more than 12% of body weight, whereas greyhound skin is 5% of weight; sloth and howler muscle are 25% of weight, macaque muscle about 40% of weight, greyhound and agouti muscle over 50% of weight. In tree shrews and galagos muscle is heavier (35%) than in pottos and slow lorises (below 28%), but bone and skin are lighter. All species differ in the segmental distribution of weight. Cats have light tails, light feet and heavy thighs, whereas howlers have heavy tails, heavy feet, and light thighs. The galagos have heavy hindlimbs and tails, the pottos and lorises have reduced tails and approximately equal fore- and hindlimbs. Convergences in segment pattern (sloths with pottos and lorises, marmosets with tree shrews, owl monkeys with galagos, cebus with macaques) as well as divergences are documented. All weight-of tissue and weight-of-segment variables are correlated directly with locomotor adaptation.     

Proximo-distal pattern regulation in deficient avian limb buds

Summary Deficient limb buds composed of prospective stylopod and autopod are able to regulate the missing intercalary zeugopod, the origin of which was investigated by heterospecific quail/chick recombinants. The associations of quail prospective autopod and chick prospective stylopod failed to regulate. The reverse combination of chick prospective autopod grafted onto a quail prospective stylopod gave rise to a three-segmented limb. In 13 out of 16 cases the regulated zeugopod was made up of both chick and quail cells. Chick cells were located predominantly along the postaxial half of the zeugopod, while the quail cells made up most of its preaxial half. In two cases, the intercalary zeugopod consisted exclusively of chick cells originating from the tip and in one case of quail cells originating from the base.These results demonstrate that during the regulative processes, the prospective values of some of the original stylopodial and autopodial cells have been shifted along the proximo-distal axis, towards the expression of more distal as well as of more proximal structures.Heteropolar stylo-autopodial or zeugo-autopodial recombinants, in which the proximo-distal axis of the base was reversed with respect to that of the tip, were unable to regulate the pattern defects and thus revealed the importance of concordant p-d polarity for regulative processes to take place between abutted tissues.     

Freeze fracture immunocytochemistry of light-harvesting pigment complexes in a cryptophyte

Summary Immunocytochemical techniques using colloidal gold as the marker have been used to examine the location of the two light harvesting pigment-protein complexes in cryptophyte chloroplasts. A comparison of post-embedding thin section labelling and freeze fracture labelling has been carried out onRhodomonas salina using polyclonal antibodies to a chlorophylla/c ₂ light-harvesting complex, phycoerythrin and the -subunit of phycoerythrin. The effect of different fixation procedures on the intensity of labelling and ac curacy of antigen location have been examined and the effectiveness of uranyl acetate and tannic acid in improving both the preservation of thylakoid structure and labelling density of phycoerythrin has been demonstrated. Freeze fracture labelling gives better spatial res olution of the different antigens than post-embedding labelling, as well as better definition of thylakoid membranes. It confirms the location of phycoerythrin in the thylakoid lumen and the location of the chlorophylla/c ₂ LHC in both appressed and unappressed thylakoid membranes.Abbreviations PE phycoerythrin - chl chlorophyll - LHC light-har-vesting complex     

Heterogeneity of tight junctions along the collecting duct in the renal medulla

Summary The tight junctions along the medullary collecting duct in the kidneys of the rat and the rabbit were studied with freeze-fracture electron microscopy and quantitated according to the number of strands and the apico-basal depth (nm) of the junctions.The most elaborate tight junctions were found in the inner stripe of the outer medulla; rat: 10.6±0.8 strands and 205±24nm; rabbit: 11.6±2.4 strands and 291±55 nm.The elaboration of the tight junctions decreased continuously towards the papillary tip. Inner zone I; rat: 9.3±2.6 strands and 186±38nm, rabbit: 9.5±2.3 strands and 247±59nm. Inner zone II; rat: 7.1±2.2 strands and 129±32nm, rabbit: 8.5±1.4 strands and 199±26nm. Inner zone III; rat: 6.0±1.6 strands and 111 + 19 nm, rabbit: 7.0±1.5 strands and 183±43 nm. In the inner zone III comprising the papillary tip tight junctions with only 1–3 strands were not infrequently seen. Preliminary findings in the kidney of the golden hamster indicate a similar decline of junctional tightness along the collecting duct.These morphological observations suggest that the permeability of the paracellular pathway of the medullary collecting duct increases towards the tip of the papilla, especially in the rat. The functional implications for the medullary recycling of urea and electrolytes, and for the urinary concentrating mechanism are discussed.In addition, the tight junctions of the papillary epithelium are described.