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ABSTRACT: The auto‐antibody response in infertile men was investigated by means of immunoenzymatic methods, dot‐immunobinding assay (DIBA), and ELISA, using, as antigens, human sperm basic nuclear proteins. Comparison was made, for the same patients, with antibody response to membrane antigens, detected by tray agglutination test (TAT), spermotoxic test (STT), and immunobead binding test (IBT). A very good agreement was observed between the two kinds of antibody responses. Thus, an ELISA or a dot‐immunobinding test with sperm nuclear proteins may be considered as a simple and sensitive method for detection of auto‐antibodies in infertile men. The reactivity in ELISA of various synthetic peptides corresponding to sequences of human protamines HP1 and HP2 was also studied: all the sera containing anti‐nuclear antibodies do not react with synthetic peptides. This observation suggests that antibodies to sperm nuclear proteins recognize conformational epitopes that are not present on small synthetic peptides.

Human complement factor H was prepared in highly purified form from fresh serum by euglobulin precipitation, DEAE-Sephacel chromatography and Sephacryl S-300 gel filtration. This preparation allowed the recovery of 37% of the initial factor H. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis revealed that factor H was homogeneous both in reduced and non-reduced media and exhibited a molecular mass of 150 kDa. Charge-shift experiments clearly showed the presence of hydrophobic sites in the factor H molecule. Charge shifts were observed with two detergent systems (Triton/sodium deoxycholate and Triton/cetyltrimethylammonium bromide). Factor H was able to bind to phenyl-Sepharose. This property allowed us to study two populations of factor H. These two populations exhibited the same physicochemical parameters, but revealed differences in their ability to aggregate in low- and iso-ionic-strength media. The molecular basis and biological significance of this heterogeneity are discussed.

Surface area and micropore size distribution were calculated from measurements of adsorption of water vapor at 25°C on a group of allophane soils from the West Indies and from Japan. The changes in pore‐size distribution on drying were measured. Specific surface area varied between 100 and 400 m2/g, and the dominant pore radius was about 7Å. Cation‐exchange capacity measured with different cations also varied with pore‐size distribution. Water retention properties were interpreted in relation to the proportion of micropores, and the chemical composition of allophane component of the soils. Pore geometry and the chemical nature of surfaces determined water retention of these allophane soils. This is in contrast to soils containing crystalline clays where the magnitude of the surface area primarily determines water retention.

An infrared method has been developed for estimating kaolinite in sediments. Hydroxyl stretching bands of kaolinite in sediments can be recorded by using a differential technique which eliminates the overlapping owing to other mineralic constituents present. By adding known amounts of an appropriate standard to the sample and by measuring intensities of the OH bands before and after the addition it is possible to calculate the proportion of kaolinite in the test sample. The choice of the added standard is made from characteristic features of the hydroxyl stretching bands. Инфракрасный метод был разработан для оценки количества каолинита в осадках. Гидроксильные растянутые полосы каолинита в осадках могут быть обнаружены с дифференциальной техники, которая устраняет влияние других присутствующих минеральных образований. Добавляя к образцу известное количество надлежащего эталона и замеряя интенсивности полос ОН до и после добавления эталона, удается вычислить долю каолинита в изучаемом образце.Выбор добавляемого эталона зависит от характерных черт гидроксильных растянутых полос. Eine Infrarotmethode für die Bestimmung von Kaolinit in Sedimenten ist entwickelt worden. Hydroxylstreckschwingungen von Kaolinit in Sedimenten können, durch den Gebrauch einer Differentialtechnik, angezeigt werden, die das Überlappen durch andere anwesende, mineralische Bestandteile, eliminiert. Indem bekannte Mengen eines angemessenen Standarts zu der Probe gegeben werden und durch Messung der Intensität der Hydroxylschwingung vor und nach der Zugabe des Standarts, ist es möglich, die Menge von Kaolinit in der Testprobe zu errechnen. Die Wahl des zugegebenen Standarts, wird mit Hilfe der charakteristischen Eigenschaften der Hydroxylstreckschwingungen getroffen. Une méthode à l’infra-rouge a été développée pour l’estimation de kaolinite dans des sédiments. Des bandes d’allongement hydroxyles de kaolinite dans des sédiments peuvent être enregistrées par l’emploi d’une technique différentielle qui élimine toute superposition due à d’autres constituents minéraux présents. Par l’addition de quantités connues d’étalon approprié à l’échantillon, et en mesurant les intensités des bandes OH avant et après l’addition, il est possible de calculer la proportion de kaolinite dans l’échantillon expérimental. Le choix de l’étalon ajouté est dicté par les phénomènes caractéristiques des bandes d’allongement hydroxyles.

Adult leg development of Tenebrio molitor: IExperimental analysis of the restoration process during morphogenesis The leg of the last instar larva, and especially the pharate pupa, of Tenebrio molitor (Colebptera) shows considerable restoration ability. Restoration refers to the regeneration of leg structures removed during the last larval instar. This process involves only those tissues adjacent to the cut surface. At each level of the leg, amputation before a characteristic time leads to the restoration of a complete leg, but thereafter the new segments formed are hypomorphic or just lobes. After an amputation close to the pupal ecdysis, fragments are obtained, and these incomplete structures show that the restoration process has ceased. Just before the pupal ecdysis the leg is withdrawn from the cuticle, so a very late amputation does not effect the leg tissue and a complete pupal and adult leg is formed. The whole of the larval leg participates in adult leg morphogenesis, and histological techniques demonstrate a great correspondence between larval and adult leg segments. The larval trochanter, however, forms the adult trochanter and the proximal part of the femur. The larval tibia forms the adult tibia plus tarsus, except for the adult claws which develop from the larval tarsal claw.