中国新石器时代居民体质类型及其承继关系

运用数理统计方法把我国新石器时代居民分为华南、华北两大类群,其中华北类群又可分为三个小类群。在人类发展过程中,南、北两群间及华北各类群间都发生过血缘混杂的过程。运用数理统计方法也可把我国旧石器晚期人类——山顶洞人和柳江人在体质特征上与我国新石器时代各组居民明显地区别开来。山顶洞人和柳江人分别代表我国旧石器晚期南北两个不同的地方类型。我国新石器时代居民的所谓澳大利亚—尼格罗人种或南亚人种特点可以追溯到我国旧石器时代晚期人类——柳江人、山顶洞人,这些特点是我国新石器时代组人类固有的特点,只不过在不同的类群中表现有所差异而已。     

北京猿人第一个头盖骨及其遗址堆积层年代的电子自旋共振测年研究

裴文中教授在60年前发现的北京猿人第一个头盖骨埋藏的确切年代至今没有获得。本文通过对北京猿人共生的古脊椎动物牙化石进行电子自旋共振(ESR)测年,分别获得了第11层北京猿人第一个头盖骨埋藏的年代为578千年,第8—9层和第3—4层北京猿人埋藏的年代分别为418千年和282千年。依据ESR、U系,TL,FT和古地磁等测年结果,本文推荐了北京猿人洞的洞穴堆积层(周口店组Q_2)年代表供读者参考。     

辽宁营口金牛山人化石头骨的复原及其主要性状

本文叙述了辽宁营口金牛山人化石头骨的保存情况、复原过程及其主要性状。从头骨壁之薄、脑量之大、以及其他的形态特征,认为它属于早期智人类型而不是猿人,对它的年代为距今28万年的报道,提出了疑问。     

Structure of the phosphopeptidomannans from flocculent and non-flocculent yeast Kluyveromyces lactis

After extraction from whole cells, and purification by gel filtration, the chemical composition and molecular mass estimation of the cell-wall phosphopeptidomannan (PPM) showed no significant difference respectively between flocculent, weakly, very weakly and non-flocculent Kluyveromyces lactis yeast strains. However, when PPMs were tested as ligands of a lectin, extracted from the flocculent strain, the PPM isolated from the flocculent and weakly flocculent strain were recognized to a higher degree than those isolated from the non and very weakly flocculent strains. Acetolysis of PPM extracted from the four strains produced five oligosaccharide fractions corresponding to mono-, di-, tri-, penta-and hexa-saccharides. The flocculent strain was characterised by a high content of di-and penta-saccharides. The ¹H NMR analysis of the oligosaccharides demonstrated that the flocculent strain contained equivalent levels of the two mannobioses: Man( 1 → 2)Man and Man( 1 → 3)Man and of the two mannotrioses Man( 1 → 2)Man( 1 → 2)Man and Man( 1 → 3)Man( 1 → 2)Man. In contrast, the non-flocculent and the very weakly flocculent strains contained a single type of mannobiose Man( 1 → 2)Man and one type of mannotriose Man( 1 → 2)Man( 1 → 2)Man.     

Mannan-degrading enzymes from Cellulomonas fimi.

The genes man26a and man2A from Cellulomonas fimi encode mannanase 26A (Man26A) and beta-mannosidase 2A (Man2A), respectively. Mature Man26A is a secreted, modular protein of 951 amino acids, comprising a catalytic module in family 26 of glycosyl hydrolases, an S-layer homology module, and two modules of unknown function. Exposure of Man26A produced by Escherichia coli to C. fimi protease generates active fragments of the enzyme that correspond to polypeptides with mannanase activity produced by C. fimi during growth on mannans, indicating that it may be the only mannanase produced by the organism. A significant fraction of the Man26A produced by C. fimi remains cell associated. Man2A is an intracellular enzyme comprising a catalytic module in a subfamily of family 2 of the glycosyl hydrolases that at present contains only mammalian beta-mannosidases.     

北京猿人第一头盖骨出土于第10层还是第11层?——与林圣龙先生商榷

北京猿人第一头盖骨的出土层位历来在学者当中存在争议。由于周口店第一地点堆积环境的复杂性以及早年发掘记录方面不可避免的一些缺陷,导致这一问题至今没有得到有效的解决。本文通过对北京猿人遗址发掘历史及堆积状况的综合对比分析,提出:北京猿人第一头盖骨出土层位相当于现今西壁剖面的第10层,即综合剖面的第11层。     

中国与日本旧石器时代晚期人类的关系

按照歧异系数,柳江人与港川人很接近,其程度和港川人二女性之间或山顶洞二女性之间接近的程度相似,柳江人与山顶洞人相去较远,山顶洞人与港川人相去较远,身材的比较也支持这些看法。     

A phylogenetic hot spot for evolutionary novelty in Middle American treefrogs

Among the various types of evolutionary changes in morphology, the origin of novel structures may be the most rare and intriguing. Here we show statistically that the origins of different novel structures may be correlated and phylogenetically clustered into "hot spots" of evolutionary novelty, in a case study involving skull elements in treefrogs. We reconstruct phylogenetic relationships within a clade of Middle American treefrogs based on data from 10 nuclear and four mitochondrial genes and then analyze morphological evolution across this tree. New cranial elements are rare among anurans and tetrapods in general, but three novel elements have evolved within this clade, with a 40% increase in the number of skull roof elements in some species. Two of these elements also evolved in a related clade of treefrogs, and these two novel elements may have each evolved repeatedly within one or both clades. The molecular phylogeny suggests striking homoplasy in cranial morphology and shows that parsimony and Bayesian analyses of the morphological data have produced misleading results with strong statistical support. The origins of the novel elements are associated with an overall increase in the ossification of dermal skull roof elements (suggesting peramorphosis) and with the evolution of a novel adaptive behavior. Our study may be the first to statistically document significant phylogenetic clustering and correlation in the origins of novel structures, and to demonstrate the strongly misleading effects of peramorphosis on phylogenetic analysis.     

中国和欧洲早期智人的比较研究

中国与欧洲的早期智人头骨在颧骨额蝶突前外侧面的朝向、颧颌角、上颌骨颧突、鼻区、上面部高度、额鼻额颌缝形状、眉间区、矢状脊、印加骨和铲形门齿诸特征的形态或出现率等方面有明显差异。那时此两大地区存在相对独立的人类进化线,其间还有一定程度的基因交流。当时此两地区的人类居群分属于不同的人种。这一假说还可从古文化和古环境的资料得到支持。     

Spreading and orientation of epithelial cells on grooved substrata

The spreading and orientation of epithelial (E) cells was studied on titanium-coated grooved substrata by light, transmission (TEM) and scanning electron microscopy (SEM). Vertical-walled grooves and V-shaped grooves, 3-60 microns deep, were produced in silicon wafers by micromachining, a process which was developed for the fabrication of micro-electronic components, and the grooved substrata were replicated in Epon. Photolithography was used to prepare photoresist-based and silicon dioxide-silicon substrata with grooves of approximately 2 and approximately 0.5 micron deep, respectively. Cell clusters were markedly oriented by all the grooved substrata examined, with the orientation index being highest for substrata with grooves of the smallest repeat spacing. Time-lapse cinemicrography showed that the grooves directed the migration of E cells, but the control was not absolute, as some cells crossed over the ridges and descended into the grooves. The 0.5 micron grooves appeared less effective than the deeper grooves in directing cell locomotion. SEM and TEM of E cells spreading on the grooved substrata demonstrated that cell processes, including lamellae and filopodia, were capable of bending around and closely adapting to groove edges. E cells did not flatten as extensively on a substratum with 22 microns deep V-shaped grooves as on a smooth surface, although some cells were markedly elongated. One mechanism proposed to explain contact guidance of fibroblasts is that linear elements of the locomotory system, such as microfilament bundles, are unable to operate when bent. The observed flexibility of epithelial cell processes and the ability of substrata with shallow grooves to orient E cells indicate that contact guidance of E cells on micromachined substrata cannot be explained by the mechanical stiffness of long linear cytoskeletal elements.     

2 trephined skulls from Schleswig-Holstein

In Schleswig-Holstein two trephined skulls are found, one belonging to a man deceased in the first half of adult age, who was buried in a stone grave of Middle Neolithic Age from Nebel on the isle of Amrum (published by Schaefer 1958, 1961). Another well preserved one, but without known site in Schleswig-Holstein, is the calvarium of a young adult presumably male showing a circular trephination without any tendency of healing. There is no symptom of a pathological change at the inner vault of the skull, but for the coronal suture gap . Striking are the grooves at both sides of the frontal bone which are quite unknown in this country. They are sulci arteriosi or nervi as is proved by Spanish skulls from Santa Cruz de Teneriffe and cases presented by Dixon (1904). EPIGENETIC TRAITS: 1. One sutural ossicle. 2. Incisura orbitalis r. 3. Threefold foramen supraorbitale 1. 4. Sulci arteriosi on the frontal bone. 5. Aplasia of left right molar (X-ray). PATHOLOGICAL CHANGES: 1. Hypoplasia of frontal sinuses. 2. Closing alveoli of first right molar. The case of a skull from Bremen (Domsdüne) demonstrates by the applied tool, that there are also trephinations in the Middle Neolithic Age.     

北京猿人第一头盖骨出土时附着于其上的是石灰华,属于第11层(下石灰华层)--答张双权、徐钦琦先生

1·张双全、徐钦琦强调北京猿人第一头盖骨出土于下洞的“红色砂质粘土层”,因此应与主堆积的第10层对比。但是在具体发现此头骨的裴文中以及头骨发现后对其进行研究的步达生的描述中都明确说该头骨埋藏在石灰华中。因此头骨应产于下洞的“下石灰华层”。2·以主堆积第10层作为参照系,下洞堆积的层位在参照系层位之下,因此其层位至少相当于《贾文》主堆积剖面的第11层,甚至可能更低。3·北京猿人遗址中的几处实例说明,在对比洞穴堆积中不同处所的地层单元时,岩性相似并不是对比的“前提条件”。关键是要有一个共有的层位作为参照系,在此基础上层位相当的地层单元才可以进行对比。下洞堆积与主堆积第11层的对比就是这样的例子。     

魏敦瑞对北京猿人化石的研究及其人类演化理论

魏敦瑞对中国猿人（现为直立人北京亚种）,化石作了详尽而深入的描述并指出了直立人的典型特征。他正确地推测, 在从猿到人的演化过程中首先是直立姿势的采用, 跟着是头骨的变化, 脑的扩张是头骨变化的动因。本世纪前半叶, 魏敦瑞第一次用一个图将所有已知的人类化石集合在一起, 作系统排列的尝试, 来表示整个人类的演化过程。他相信所有化石人类属于一个种, 能够互相杂交, 人类不是起源于一个地方, 而是起源于几个地方。他反对南方古猿曾经参与人类进化的说法, 代之以认为人类进化的早先各期是巨人阶段, 但是他的巨人理论迄今没有化石的证据。关于现代人的起源, 多地区起源说和非洲起源说目前正在激烈争论之中。     

Mannan-Degrading Enzymes from Cellulomonas fimi

The genes man26a and man2A from Cellulomonas fimi encode mannanase 26A (Man26A) and β-mannosidase 2A (Man2A), respectively. Mature Man26A is a secreted, modular protein of 951 amino acids, comprising a catalytic module in family 26 of glycosyl hydrolases, an S-layer homology module, and two modules of unknown function. Exposure of Man26A produced by Escherichia coli to C. fimi protease generates active fragments of the enzyme that correspond to polypeptides with mannanase activity produced by C. fimi during growth on mannans, indicating that it may be the only mannanase produced by the organism. A significant fraction of the Man26A produced by C. fimi remains cell associated. Man2A is an intracellular enzyme comprising a catalytic module in a subfamily of family 2 of the glycosyl hydrolases that at present contains only mammalian β-mannosidases.     

Effects of tryptophan to phenylalanine substitutions on the structure, stability, and enzyme activity of the IIAB(Man) subunit of the mannose transporter of Escherichia coli.

The hydrophilic subunit of the mannose transporter (IIAB(Man)) of Escherichia coli is a homodimer that contains four tryptophans per monomer, three in the N-terminal domain (Trp12, Trp33, and Trp69) and one in the C-terminal domain (Trp182). Single and double Trp-Phe mutants of IIABMan and of the IIA domain were produced. Fluorescence emission studies revealed that Trp33 and Trp12 are the major fluorescence emitters, Trp69 is strongly quenched in the native protein and Trp182 strongly blue shifted, indicative of a hydrophobic environment. Stabilities of the Trp mutants of dimeric IIA(Man) and IIAB(Man) were estimated from midpoints of the GdmHCl-induced unfolding transitions and from the amount of dimers that resisted dissociation by SDS (sodium dodecyl sulfate), respectively. W12F exhibited increased stability, but only 6% of the wild-type phosphotransferase activity, whereas W33F was marginally and W69F significantly destabilized, but fully active. Second site mutations W33F and W69F in the background of the W12F mutation reduced protein stability and suppressed the functional defect of W12F. These results suggest that flexibility is required for the adjustments of protein-protein contacts necessary for the phosphoryltransfer between the phosphorylcarrier protein HPr, IIA(Man), IIB(Man), and the incoming mannose bound to the transmembrane IIC(Man)-IID(Man) complex.     

大荔人化石地点第二次发掘简报

对大荔人化石地点进行再次的发掘,不仅发现了新的文化层,而且在含大荔人化石层中找到了384件石器和一些哺乳动物化石,为探讨“大荔人”文化的性质及其时代提供了有意义的资料。     

Characterization of glycosylated variants of beta-lactoglobulin expressed in Pichia pastoris

Glycosylated variants of beta-lactoglobulin (BLG) were produced in the methylotrophic yeast Pichia pastoris to mimic the glycosylation pattern of glycodelin, a homologue of BLG found in humans. Glycodelin has three sites for glycosylation, corresponding to amino acids 63-65 (S1), 85-87 (S2) and 28-30 (S3) of BLG. These three sites were engineered into BLG to produce the variants S2, S12 and S123, which carried one, two and three glycosylation sites, respectively. The oligosaccharides on these BLG variants ranged from (mannose)(9)(N-acetylglucosamine)(2) (Man(9)GN(2)) to Man(15)GN(2) and were of the alpha-linked high mannose type. The variant S123 exhibited highest levels of glycosylation, with the range of glycans being Man(9-14)GN(2). Digestion of S123 with alpha-1,2 linkage specific mannosidase resulted in a single product corresponding to Man(6)GN(2). These results indicated a glycosylation pattern consisting of a Man(5)GN(2) structure extended by 4-9 mannose residues attached mainly by alpha-1,2 linkages. The results also indicated extension of the Man(5)GN(2) structure by a single alpha-1,6-linked mannose. The N-linked glycosylation pathway in P.pastoris is significantly different from that in Saccharomyces cerevisiae, with the addition of shorter outer chains to the core and no alpha-1,3 outer extensions.     

Evaluation of an endo-β-mannanase produced by Streptomyces ipomoea CECT 3341 for the biobleaching of pine kraft pulps

An endo-beta-mannanase (EC 3.2.1.78) from Streptomyces ipomoea CECT 3341 was purified and applied to the biobleaching of pine kraft pulps. The maximum level of endo-beta-mannanase activity (0.6 units ml(-1)) was achieved after 4 days of growth in a medium containing locust bean gum and yeast extract. Zymograms revealed mannanase bands (Man) with high and low electrophoretic mobility on the second and seventh days of incubation (Man1, Man3) and three bands of high, medium and low mobility from the third to sixth days of growth (Man1, Man2, Man3). Although these exhibited different molecular masses, their amino-terminal sequences were identical. The action of proteases detected in the culture supernatant could be responsible for such events, suggesting that only one endo-beta-mannanase is produced by S. ipomoea. The purified Man3 exhibited a molecular mass of 40 kDa, an isoelectric point of 4.0 and an optimal temperature and pH reaction of 55 degrees C and 7.5, respectively. It was strongly inhibited by Ag+, Hg2+, Al3+ and Fe3+, and was strongly activated by Mn2+. The ability of the purified endo-beta-mannanase to improve the bleachability of pine kraft pulp, when applied with alkaline extraction, was demonstrated by an increase in the pulp brightness (1.7%, using the International Standards Organisation's test) and an absence of variations in the viscosity values. A relationship between the increase in pulp brightness and the presence of manganese in the pulps could be established.     

Cell type-dependent variations in the subcellular distribution of alpha- mannosidase I and II

alpha-mannosidases I and II (Man I and II) are resident enzymes of the Golgi complex involved in oligosaccharide processing during N-linked glycoprotein biosynthesis that are widely considered to be markers of the cis- and medial-Golgi compartments, respectively. We have investigated the distribution of these enzymes in several cell types by immunofluorescence and immunoelectron microscopy. Man II was most commonly found in medial- and/or trans- cisternae but showed cell type- dependent variations in intra-Golgi distribution. It was variously localized to either medial (NRK and CHO cells), both medial and trans (pancreatic acinar cells, enterocytes), or trans- (goblet cells) cisternae, or distributed across the entire Golgi stack (hepatocytes and some enterocytes). The distribution of Man I largely coincided with that of Man II in that it was detected primarily in medial- and trans- cisternae. It also showed cell type dependent variations in its intra- Golgi distribution. Man I and Man II were also detected within secretory granules and at the cell surface of some cell types (enterocytes, pancreatic acinar cells, goblet cells). In the case of Man II, cell surface staining was shown not to be due to antibody cross- reactivity with oligosaccharide epitopes. These results indicate that the distribution of Man I and Man II within the Golgi stack of a given cell type overlaps considerably, and their distribution from one cell type to another is more variable and less compartmentalized than previously assumed.     

Fibroblasts on micromachined substrata orient hierarchically to grooves of different dimensions

Contact guidance was studied by light, scanning (SEM) and transmission electron microscopy (TEM) in cultures of human gingival fibroblasts cultured on grooved surfaces. The grooves were originally produced in silicon wafers by micromachining, a process which is based on the methods used to fabricate microelectronic components, and the grooved surfaces were then replicated in Epon. Micromachining enables precise control of groove depth, groove spacing, and groove shape to be obtained. In silicon wafers with appropriate crystal orientation, a second smaller set of grooves, called the minor grooves, is found on the floor of the major grooves. The minor grooves are oriented at a 54 degree angle to the major grooves, so that cells cultured on such surfaces are concurrently exposed to grooves of different dimensions which direct cell migration in different directions. Marked fibroblast alignment with the major grooves was observed both within the grooves and in the intervening flat ridges between the grooves. In addition, shallow and closely spaced grooves in epon or titanium-coated polymer or silicon were also capable of orienting fibroblasts. Although the minor grooves were able to orient fibroblasts in the absence of any other orienting influence, when fibroblasts were concurrently exposed to major and minor grooves the cells aligned themselves with the major grooves. TEM showed that the cellular filamentous cytoskeletal elements reflected the orientation of the cell as a whole. Fibroblasts on grooved substrata appeared to have more filopodia and to round up more frequently than fibroblasts cultured on flat substrata. It is suggested that both the mechanical properties of the cytoskeleton as well as the durability of the cellular attachment to groove edges may play a role in the contact guidance effected by grooved surfaces produced by micromachining.