Biomedical subjects

C Cataldo

Publications and source records attributed to C Cataldo.

At least 19 recordsLinked to original sources

PubMed2003

Sanitary quality of marine sediments and sands from an Italian beach.

Microbiological surveys were carried out on marine sands and sediments collected at a sandy beach along a coastal area close to Rome, Italy. Low densities of faecal indicator bacteria were recovered, and among them enterococci outnumbered the coliforms. The group of staphylococci was in a fairly constant concentration throughout the period of sampling. Some statistically significant correlations were calculated between yeasts and moulds, Escherichia coli and enterococci and between the latter and Clostridium spores. The data obtained could be a reference point for further studies.

Bacteria↗

PubMed2002

Fate of bacterial indicators, viruses and protozoan parasites in a wastewater multi-component treatment system.

The extent of reduction in selected microrganisms was tested at a multi-component wastewater treatment plant that treats sewage for a potential re-use in agriculture. The aim of the investigation was to evaluate possible reciprocal correlation among the different microrganisms and to compare the removal of two encysted pathogenic protozoa with that of microbial indicators, Clostridium perfringens spores, enteroviruses and bacteriophages. Samples collected included the raw wastewater, the chlorinated effluent and the effluent after an ultraviolet light treatment. All of the raw sewage samples were positive for Cryptosporidium oocysts and Giardia cysts, as well as for the other microorganisms tested but the bacteriophage B40-8. The data obtained confirm the removal efficiency of the entire process for indicator bacteria but also show the low and variable removal efficiency for the other microbial parameters, such as Giardia and Cryptosporidium, enteroviruses and Clostridium perfringens spores. Reciprocal correlation between Cryptosporidium and Giardia (oo)cysts and the other microbial groups was not demonstrated. The results confirm the resistance of Clostridium perfringens spores, enteroviruses and protozoa to chlorination and demonstrate the relative persistence of these organisms in the effluents even during the ultraviolet light treatment. The yields also emphasise the influence of the analytical method for the determination of protozoan parasites.

Animals↗

PubMed1991

Three dimensional reconstruction of human pachytene spermatocyte nuclei of a 17;21 reciprocal translocation carrier: study of XY-autosome relationships.

A study of XY-autosome relationships at the pachytene stage in an infertile 17-21 reciprocal translocation carrier was undertaken by means of three dimensional reconstruction. Synaptonemal complexes and the sex vesicle were analysed on electron microscopic serial sections and the reconstruction was performed on transparent sheets and on a Samba 2000 (Alcatel TITN) image analysis system. All asynapsed segments were entirely included in the sex vesicle, the chromatin fibre of the autosomes and sex chromosomes being tightly intermingled. In one nucleus, the four arms of the quadrivalent were paired, except around the breakpoints where an interstitial asynapsis was observed. In the other nuclei, a terminal asynapsis involving one or two arms of the quadrivalent was found. In the sex vesicle, autosomal asynapsed segments showed the same morphological characteristics as those of X and Y chromosomes. This observation agrees with the hypothesis of the extension of gene inactivation from sex chromosomes to autosomes.

Cell Nucleus↗

PubMed1988

Three-dimensional ultrastructure and quantitative analysis of the human Sertoli cell nucleolus.

The nucleolus of the human Sertoli cell displays a spontaneous segregation of its components and has only one or 2 large fibrillar centers. The 3-dimensional reconstruction and quantitative analysis of its components was undertaken using a Quantimet 900 image analysis system in order to define the spatial relationships between the dense fibrillar component and the fibrillar center and especially to investigate whether threads of dense fibrillar component exist independently, without being linked to a fibrillar center. Our 3D reconstructions demonstrated that the dense fibrillar threads or sheets were never independent of fibrillar centers. These structures belonged to a continuous network that joined the layer of dense fibrils surrounding the fibrillar center. When the nucleolus contained 2 different-sized fibrillar centers, quantitative analysis showed that there was a proportional relationship between the volume of the dense fibrillar component and the volume of the fibrillar center. These data, compared with those previously obtained by means of autoradiographic techniques, suggest that the rDNA-containing chromatin passes through the fibrillar center and unwinds from there into the dense fibrillar component.

Cell Nucleolus↗

PubMed1985

Three-dimensional analysis of fibrillar centers and associated chromatin in the nucleolus of human oocytes in primordial follicles.

The intranucleolar localization of fibrillar centers and their relationships with nucleolus-associated chromatin were determined in stereopairs of human oocyte nucleoli obtained by computer reconstruction of serial sections. This study showed that there was no numerical relationship between the number of fibrillar centers and the number of chromosomal NORs. The three-dimensional reconstruction demonstrated that the majority of fibrillar centers was directly connected with the nucleolus-associated chromatin.

Adult↗

PubMed1980

Development of the thyroid gland in the rat fetus in vivo. An ultrastructural and radioautographic study.

A study of the differentiation of the thyroid follicles was carried out in rat fetuses between day 14 of pregnancy, when cellular polarization begins and day 18, when completely formed follicular lumina are differentiated. After day 18, only the shape and the size of the lumina undergo modifications. The mechanism of folliculogenesis involves the participation of several structures. At 14 days of pregnancy, adherens type contact zones with membrane densification appear between the cells. These junctional zones spread out and form infoldings which deeply penetrate the cytoplasm. Golgi vesicles migrate to these zones and they fuse among themselves and with the contact membranes : follicular cavities result which can be recognized as soon as day 16 of pregnancy. A radioautographic study showed the beginning of iodide organification at 17 days 11 hours of pregnancy. From this time onward silver grains were seen over the follicular cavity, even it is still incompletely formed.

Animals↗

PubMed1979

Frequency and distribution of tubulo-filamentous nuclear inclusions in the celiac ganglion of the cat as revealed by serial sections.

On sections at random of a cat celiac ganglion we counted 68 sections of nuclear inclusions (NI) for 320 sections of neuronal nuclei, i.e. an "apparent' frequency of 0.20. As revealed by serial sections the "actual' frequency is higher since the 5 nuclei entirely explored exhibit 19 NI. Such a study shows that each nucleus may contain at least 3 and up to 5 different tubulo-filamentous NI.

Animals↗

PubMed1979