Serum immunoglobulin levels in various forms of meningococcal infection and in meningococcus carriers

The levels of serum IgG, IgA and IgM were examined in 191 adults including 103 patients with various forms of meningococcal infection, 32 meningitis convalescents and 56 carriers, in order to elucidate the causes of different susceptibility to the meningococcal infection. The IgD level was determined in 54 meningitis patients as well as in convalescents and carriers. The amount of immunoglobulins was determined by radial immunodiffusion. The level of IgG at the beginning of the disease in patients with the generalized forms of meningococcal infection (meningitis, meningitis combined with meningococcaemia, meningococcaemia) was found to be considerably lower than in healthy subjects. The levels of all immunoglobulins, particularly of IgA and IgM, increased in the course of the disease. The levels of IgG, IgA and IgM in meningitis convalescents a year after recovery were found to be the same as in the controls. The levels of IgG, IgA and IgM in patients with meningococcal nasopharyngitis were significantly lower than in healthy subjects. The carriers showed a decreasd level of IgA and a considerably increased level of IgG while the levels of IgM and IgD did not differ from the control.     

Localization of ATPase activity, respiration and ultrastructure of wheat root cells with modulated ion conductivity of plasma membrane

Changes in the localization of ATPase activity, respiration and ultrastructure of wheat root cells with modulated ion conductivity of plasma membrane were studied. A 2 h treatment of excised root with valinomycin (20 microM), N,N-dicyclohexylcarbodiimid (100 microM), gramicidin S (20 microM) and chlorpromazine (100 microM) caused an increased loss of potassium by cells, a decreased respiration and changes in the localization of ATPase activity and in cell ultrastructure. Differences in the observed changes may be conditioned by different mechanisms of action of the membrane active compounds used. It is concluded that changes in the localization of ATPase activity and ultrastructure may indicate some early specific responses of root cells, whereas the increase in the ion conductivity and decrease in respiration under disruption of ion homeostasis caused by membrane active compounds indicate unspecific responses of cells.     

Characteristics of the morphofunctional changes in the liver of C3HA mice due to immunization with a homogenate of normal syngeneic liver

Immunization of C3HA mice with homogenate of normal syngeneic liver at a dosage causing elevation of antitumor resistance damages the liver of recipients. The damage involves the formation of foci of necrosis and the alteration in activities of some tissue specific and embryonal enzymes. The damage is reversible; its degree and the rate of reverse depends on a dosage of homogenate injected.     

Induction of arginase activity in the splenocytes of C3HA mice undergoing partial hepatectomy

In splenocytes of C3HA mice after partial hepatectomy the increase in arginase activity is found. It correlates with the increase in cytotoxic splenocyte activity towards tumor cell-target. The suspension without cells capable of adhesion and phagocytosis shows decrease in arginase activity up to 50%. But the enzyme activity is still higher than in splenocytes of intact mice.     

The epidemiology of acute intestinal infections of undetermined etiology in children

Materials obtained in the study of conditions for contacting acute enteric infections of uncertain etiology, based on the analysis of the age structure of patients, the structure of clinical diagnoses and the monthly dynamics of cases registered in one of the districts of Moscow for 3 years (1984-1986), are presented. An important role of the alimentary factor in the spread acute enteric infections of uncertain etiology among the population of different age groups and everyday contacts in the spread of such infections among young children has been shown. The authors put forward a suggestion concerning the formation of natural immunity to infective agents, serving as etiological factors in the development of enteric infections of uncertain etiology, in children of preschool age.     

新生隐球菌嗜中枢性感染机制的研究进展

新生隐球菌是临床上最重要的侵袭性病原真菌之一,可感染免疫抑制和免疫正常人群引发具有致命威胁的隐球菌性脑膜脑炎.近年来,隐球菌嗜中枢神经系统感染的机制研究取得了长足的进展,隐球菌参与侵袭中枢神经系统的相关毒力因子及多条宿主细胞应答信号通路相继被发现.