Two immunologically active polysaccharides were isolated from Nocardia asteroides (Poly I Na and Poly II Na) and N. brasiliensis (Poly I Nb and Poly II Nb). These polysaccharides were isolated from cell extracts and purified by methanol precipitation, chloroform extraction of extraneous material, and deproteinization with trichloroacetic acid. The crucial step used for separation of Poly I and Poly II from both nocardias was differential solubility. From dried preparations containing both polysaccharides, Poly I was solubilized at pH 10, whereas Poly II remained insoluble and was subsequently solubilized at pH 5. Poly I Na and Poly I Nb are apparently the same. Arabinose and galactose were the monosaccharide constituents of these polysaccharides, and their molar ratios were similar. Furthermore, PolW I Na and Poly I Nb crossreacted in agar diffusion precipitin tests with rabbit antisera prepared against either N. asteroides or N. brasilies. Either polysaccharide absorbed serum antibodies against the other. These polysaccharides can be regarded as groupspecific. Poly II Na and Poly II Nb are different and species-specific. They are composed of arabinose, galactose, and mannose but exhibit different molar ratios of these sugars according to species. They reacted only with homologous antisera.
A precise demonstration of the presence of circulating antibodies in patients with mycetoma due either to Nocardia brasiliensis or Nocardia asteroides is lacking. Laboratory animals immunized with these microorganisms show antibodies in their blood, as revealed by agglutination, precipitation or complement fixation reactions( 1-3) ; however, all of these lacked the requisite specificity.The literature also contains contradictory reports regarding skin hypersensitivity studies carried out with these microorganisms (4-8).The materials* used to elicit responses have been likewise, crude and non-quantitative.This paper is concerned with the immunological response of patients with mycetoma due to N . brasiliensis, using purified Nocardia polysaccharides as antigens for serology, and purified Nocardia proteins to evoke skin reactions.Materials and methods. Serological tests were carried out using Ouchterlony's( 10) double-diff usion precipitin reaction in agar. Sera from 14 patients with mycetoma due to N . brasiliensis were tested and compared with a number of sera from tuberculous patients, healthy individuals, as well as with sera from patients with other infectious and non-infectious diseases.As antigens for the precipitin reactions we used 2 polysaccharides isolated from N . brasiliensis (Poly I Nb and Poly I1 Nb) and 2 others from N . asteroides (Poly I Na and Poly I1 Na). Poly I Na and Poly I Nb are apparently the same and are regarded as group specific. Arabinose and galactose are the monosaccharide constituents of Poly I *Th: term "sensitin" has been suggested(9) for a nonantigenic substance prepared from a microorganism, capable of revealing sensitivity of the delayed type which is evoked by the organism. Tuberculin, histoplasmin and coccidioidin are regarded as examples of "sensitin".Nb and Poly I Na and their molar ratios are similar. They cross-react when tested with rabbit antisera prepared against either Nocardia species. Furthermore, either polysaccharide I absorbed serum antibodies against the other.Poly I1 Nb and Poly I1 Na are species specific; they react with rabbit antisera prepared against the homologous Nocardia species only. They contain mannose in addition to arabinose and galactose, with the molar ratios of the last 2 sugars variable according to species. A full account on the purification and the immunological characterization of these polysaccharides is being reported elsewhere ( 1 1 ) .Sera obtained from the patients had been preserved at 0°C after addition of merthiolate to a final concentration of 1:1O,OOO. Usually, 0.1 ml of serum was deposited in the center well of the agar plates, and 0.1 ml containing 50 pg of each of the purified polysaccharide antigens was placed in the peripheral wells. The plates were incubated at 2 1 "C for up to one week in a moist chamber. All precipitin bands that appeared were visible between 24-72 hours of incubation.Skin tests. For these tests we used purified protein derivatives from N . brasiliensis and from N . asteroides (RS-81). For comparison, a puri...
Millium colloid is a rare cutaneous deposition disorder of unknown aetiology on lightexposed skin. It presents as flesh-coloured or yellow papules. A skin biopsy and light microscopy study is required for diagnosis, with findings of fissured eosinophilic colloid masses in the papillary dermis, with solar elastosis that is separated from the epidermis by a Grenz zone containing normal collagen. There is no single effective treatment. We present a case report of a 42-yearold man with papular lesions on the dorsum of both hands and a history of prolonged sun exposure. © 2015 Sociedad Médica del Hospital General de México. Published by Masson Doyma México S.A. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/). PALABRAS CLAVE Millium coloide; Fotoexposicion Milium Coloide del Adulto. Una entidad subdiagnosticada y de difícil tratamientoResumen El millium coloide es una enfermedad de depósito, presente en áreas fotoexpuesta y de etiología desconocida. Clínicamente se identifica como lesiones de aspecto papular de color rosa o amarillo. Para su diagnóstico es necesario realizar una biopsia de piel para microscopía de luz, donde se observan masas eosinofílicas fisuradas en la dermis papilar en presencia de elastosis solar y una zona de Grenz de fibras elásticas que separa la lesión del resto de la epidermis. Hasta el momento no existe un tratamiento de elección. Se presenta el reporte de un caso de un paciente masculino de 42 años con lesiones de aspecto papular en dorso de manos, con el antecedente de exposición crónica a la luz solar.
of the group-specific polysaccharide of Nocardia brasiliensis. J. Bacteriol. 90:571-574. 1965.-The groupspecific polysaccharide of Nocardia brasiliensis was further purified, yielding an amorphous white material with the following characteristics: [a]D20 = + 48; nitrogen, 0.5%; phosphorus, 0.1%; and ash as sodium, 0.8%. The polymer is made of D-arabinose and D-galactose in a molar ratio of 3:1, and no other sugars were detected. Mild hydrolysis liberates mainly arabinose. The polysaccharide consumes 3.46,umoles of periodate per mg of polymer in 15 days at 4 C (this value remains constant after 4 more days). Oxidation results in destruction of two of the arabinose, with the formation of two glycerols after borohydride reduction and hydrolysis. The polysaccharide oxidized by periodate and reduced under mild acid hydrolysis at 20 C yields glycerol and a polymer formed by galactose and arabinose (in a ratio of 1:1) which is resistant to a second oxidation. Therefore, the polysaccharide is probably formed by a main chain of glactose linked 1,3 and arabinose linked 1,2 or 1,3 or both, and nonreducing side chains of arabofuranose residues. The intact polysaccharide cross-reacts with sera from patients with active tuberculosis, and this, as well as the homologous reaction, is abolished by oxidation with periodate.
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