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I Santino

Publications and source records attributed to I Santino.

5 recordsLinked to original sources

TWAR: a new chlamydial species?

In 1986 Grayston and coworkers termed TWAR (or Taiwan Acute Respiratory) a new strain of Chlamydia which has still not received an exact taxonomic classification. In fact, whereas initially the TWAR strain was classified as C. psittaci because of its oval-shaped, glycogen free, dense inclusions, recent studies on the immunological analysis, DNA analysis and ultrastructural morphology, would seem to indicate that TWAR is a new Chlamydial species, whose proposed name as C. pneumonia. TWAR is mainly responsible for respiratory syndrome varying in gravity from a slight form to pneumonia, and is liable to give rise to epidemic forms; in addition, more recently, certain Authors have postulated its involvement in the pathogenesis of ischemic cardiopathy.

Chlamydia

[Chlamydiae. 1].

Throughout the animal kingdom the Chlamydiae are among the most common and ancient pathogens, but only in the 1966 they were classified by Page in the same genus because of different nosological pictures that they cause, while more recently were identified as bacteria. Chlamydiae have been divided into two species: C. trachomatis and C. psittaci. In 1986 Grayston et al. proved the etiological role of a "new chlamydial strain", named TWAR (Taiwan-Acute Respiratory), in human pneumonia and bronchitis; TWAR is distinguishable from other Chlamydiae and possibly represents a new entity. The Chlamydiae are non-motile, metabolically poor bacteria, completely lacking of any enzimatic system for energy production (ATP) and for this reason are obligate intracellular parasites; they poses group-specific, species-specific and type-specific antigens. Four series of surface proteins were identified as responsible for their pathogenic properties, while many Authors consider a particular lipopolysaccharidical acid, group antigen, as a real LPS. These bacteria poses an unique developmental cycle with production of two type of particles different for metabolic and infecting characters: elementary body and reticulate body. The Chlamydiae have a broad spectrum of host. They cause persistent or chronic infections and their survival is insured by the elementary body. The Chlamydiae stimulate the humoral and the cellular-mediate immunity system and are capable of survival in the monocytes and macrophages.

Adult

[Chlamydiae. 2. Chlamydia trachomatis].

The Chlamydia trachomatis (C.t.) causes trachoma, inclusion conjunctivitis, lymphogranuloma venereum and it is the more frequent responsible of sexually transmitted infections; in fact, only in the United States, 3-4 million of people suffer from these infections each year. Besides, there are many secondary infections that may cause sterility in man and woman. Risk factors, for venereal infections owed to C.t., are related to the number of sexual partners, age, socioeconomics status and sexual preference. More frequently, the C.t. infects persons that begin sexual activity earlier, those who have many sexual partners and an higher level of education. The direct diagnosis for detecting C.t. can be performed with the citologic test, cell culture, direct immunofluorescence and enzyme immuno-assay. Although, the cell culture is the technique of choice, at present the immunofluorescence and enzyme immuno-assay are the methods preferred because of rapidity and esecution. The indirect diagnosis can be achieved by the complement fixation, indirect immunofluorescence and enzyme immuno-assay tests. In this case, excluding the complement fixation test not more reliable, the method of choice depends, above all, upon the kind of infection in progress. Tetracycline, erythromycin, rifampicin and cloramphenicol are considered the treatment of choice.

Adult

[Bacterial anti-Ig activity].

The production of the five classes of immunoglobulins represents the highest grade of the various system of defence the man puts in act against the microbial attack. So bacteria fight in several levels across the different stages of human antibodies synthesis processes and action, trying for cancelling the effect. Therefore, a more exact definition of the mechanisms of bacterial actions against human immunoglobulins would permit us to intervene in a more efficacious way in favour of defence powers of the human organism. In this way we could improve the knowledge of the bacterial damage process, increase the means of human immunization, and our therapy attempts. We analyzed therefore in this study the different defence mechanisms that bacteria use against human immunoglobulins. Bacteria can avoid "a priori" or divert antibodies formation, by synthesis of surface structural identical to components of the host. Bacteria can stop or hinder transmission of antigenic message working against the phagocytosis mechanisms. Bacteria can stop or lessen antibodies synthesis process. Bacteria can avoid specific contact with antibodies, especially, by masking the microbial surface. Bacteria can change their superficial structures to avoid antibodies action. Bacteria can destroy antibodies by synthesis of protease activity capable of hydrolyzing globulins.

Antibodies, Bacterial