[Microorganism "Montezuma" of the order Rickettsiales: the potential causative agent of tick-borne disease in the Far East of Russia]. / Mikroorganizm "Montezuma" iz poriadka Rickettsiales: potentsial'nyi vozbuditel' kleshchevogo transmissivnogo zabolevaniia na Dal'nem Vostoke Rossii.

A new microorganism, tentatively named "Montezuma" was detected in ticks and in specimens (blood, bioptic specimens of the primary affect) taken from patients with an acute fever disease, etiologically linked with the bites of Ixodes ticks in the Far East of the Russian Federation. After sequencing the products of the amplification of DNA isolated from ticks with wide-spectrum primers new primers were developed, highly specific to the unusual sequence thus obtained. The study revealed that ticks of the species Ixodes persulcatus (97%) and Haemophysalis concinnae (5%) contained DNA of this microorganism. The same DNA was detected in materials taken from the patients. The phylogenetic analysis of the gene showed that this organism formed an independent and well defined branch within the order Rickettsiales. The nearest homology (89%) was observed with recently detected endosymbiotes Acanthamoeba. The similarity with their relatives from the families Rickettsiaceae and Anaplasmataceae of the order Rickettsiales was within 81-86%, which made it possible to infer the existence of, probably, only a new genus, but also a family. The isolated DNA belonged, supposedly, to the new microoganism which caused a tick-borne disease in humans, transmitted through bites of Ixodes ticks, and was, supposedly, widely spread in the southern area of the Khabarovsk Territory.

[Proliferative processes in the epithelium of colon mucosa in patients with Salmonella infection during first 24 hours after the onset of the disease]. / Proliferativnye protsessy v épitelii slizistoi obolochki tolstoi kishki u bol'nykh sal'monellezom v pervye sutki bolezni.

DNA synthesis in the epithelium of a distal portion of human colon was studied by radioautography with 3H-thymidine in patients during the first 24 hours of gastrointestinal salmonellosis. All 13 patients aged 18-50 years were admitted to hospital during 9-20 hours after the disease onset. Nobody had a background of gastrointestinal pathology. The control group consisted of samples from sigmoid colon epithelium of 30 healthy individuals. The labelled nuclei index (LNI) was 5.16 +/- 0.27%, the intensity of labelling (IL) was 13.65x +/- 0.82. Endoscopic and pathomorphological studies of colonic mucosa in salmonellosis by the end of the first 24 hours of the disease showed superficial inflammation. Increased LNI (11.48 +/- 1.07%, p < 0.05) characterized activation of proliferation and increased IL (22.24 +/- 2.1, p < 0.05) showed intensification of DNA synthesis. Additionally, in one third of cases enlargement of proliferation compartment up to 2/3 crypt was noticed. It is unlikely that in this situation immune mechanisms play the key role, it seems that a direct stimulation of proliferative processes by a bacterial agent takes place.

[Characteristic of proliferative processes in colonic mucosa in acute salmonellosis]. / Kharakteristika protsessov proliferatsii épiteliia slizistoi obolochki tolstoi kishki v ostrom periode sal'monelleza.

DNA synthesis in the epithelium of a distal portion of human colon was studied at radioautography with 3H-thymidine through the first three days of gastrointestinal salmonellesis. Control studies were performed on the mucosa of the sigmoid colon of healthy persons undergoing rectoromanoscopy because of epidemiological reasons. No pathological changes were found in these specimens, the labeled nuclei index (LNI) was 5.16 +/- 0.27%, the label intensity (LI) which characterizes the rate of DNA synthesis was 13.65 +/- 0.82. Group 1 consisted of 18 patients having slight inflammation without erosions, ulcerative and haemorrhagic changes. We found significant activation of proliferation (LNI = 15.09 +/- 0.9%, LI = 22.23 +/- 1.9; p < 0.05) in this group compared to the control one. 15 patients with salmonella-induced hemorrhagic colitis formed group 2 in which LNI and LI were also increased (LNI = 9.89 +/- 1.0%, LI = 19.3 +/- 2.3; p < 0.02) vs. control group, but these changes seemed to be significantly weaker than those in group 1 (p < 0.01). It is inferred that rates of proliferation in colon epithelium in acute salmonellosis are significantly higher than in healthy epithelium but activity of these processes decreases with growing severity of inflammation.