[Viral respiratory infections]

A brief account of the general features of viruses and their importance in the biological world is followed by a description of the main viruses responsible for respiratory infections in man, with particular reference to matters of morphology, epidemiology, pathology, and (where possible) prophylaxis. Lastly, the modalities for the isolation of such viruses and the main serological reactions employed in diagnosis are explained.

[Hemagglutination inhibition test for rubella virus: control of the removal of complete non-specific inhibitors]

A method showing whether the inhibitory activity of a serum, with a low rubella HAI titer, is due to specific antibodies, or to the incomplete removal of non-specific beta-lipoprotein inhibitors, is described. Serum absorption with Staphylococcus aureus removes over 95% of the IgG, and a smaller amount of the other Ig, beta-lipoproteins and albumin, whereas Staphylococcus epidermidis absorbs about 20% of all Ig, beta-lipoproteins and albumin. This means that a serum with anti-rubella IgG displays the same, or at most a slightly depressed HAI titer after absorption with S. epidermidis, whereas S. aureus leads to at least a 16 fold reduction. By contrast, a serum with no antibodies, in which inhibition is due to non-specific inhibitors, will show an equally reduced HAI titer after absorption with each strain.

Interferon production on mouse fibroblasts induced by various viruses

The interferon (IF) inducing ability of some DNA and RNA viruses on mouse CCL-1 cells was investigated. The F and H strains of Newcastle disease virus (NDV) and Sendai virus proved to be the best inducers. GD-7, Mengo and Vesicular stomatitis virus (VSV) were middle inducers, Herpes simplex 1 (HSV 1) was a weak inducer, and Adenovirus 12 and Semliki forest (SFV) were non-inducers. Moreover antiviral resistance induced by the same viruses and IF production generally followed parallel paths.

Polygenic control of interferon production induced by poly I:C in vivo. Brief report

Poly I:C-induced interferon production shows quantitative differences in various mouse strains depending on multiple interactions among genes located both inside and outside the major histocompatibility complex. Moreover, circulating interferon levels do not appear to be under direct genetic control but, rather, to depend on the gene-coded intensity of specific recognition of the inducer.

Use of formalinized human cord blood erythrocytes in the haemagglutination inhibition test for rubella

The use of formalinized human cord blood erythrocytes in the haemagglutination inhibition test for rubella is proposed. These cells retain their sensitivity to rubella virus haemagglutinin for several months and give serum titres comparable with those obtained with fresh cord blood erythrocytes.

Effect of synthetic polynucleotides on the growth of transplantable tumours in BALB/c mice

The effect of BALB/c mice pretreatment with tumour cells (a mammary adenocarcinoma, ADK-1t and an IgA secreting plasmocytoma, MOPC-315) adsorbed with poly I:C, poly I and poly C is examined. Only mice pretreated with cells of both tumours adsorbed with poly I:C and poly C proved to be extensively protected against challenge by homologous untreated tumour cells, whereas this was not so in the case of poly I. A possible explanation of this phenomenon is discussed.

[Routes of spread of the current rabies epizoonosis in Europe]

The present report describes the spreading paths of the rabic epidemic that is rapidly reaching Italy from Central Europe. The epidemiologic situation of neighbouring countries is examined and the sanitary measures undertaken in Europe against epidemic are compared.

[General considerations on the interferon system]

In this review some interesting aspects of interferon and its present perspectives for a practical utilization in human viral infections and in oncological therapy are described. After an evaluation of general characteristics of IF, some particular problems are considered about this system as that of IF and poly I:C interaction with cellular membranes, genetic control of IF system, IF and its inducers influence on immune reactivity and human tumours cells IF inducing ability and sensitivity. Finally are described some data obtained in various Institutes with IF on human virosis and those obtained on human and animal oncology with IF and interferon inducers.

[Isolation of Salmonella in the Piedmont from 1975 to 1978, with designation of rare strains and evaluation of the frequency of the serotypes]

In the present study the data concerning the isolation of Salmonella strains in Regione Piemonte during the years 1975-1978 are reported. During this period, using serological methods 2934 Salmonella strains have been typed which resulted to belong to 69 different serotypes. We have also compared the frequency of the different serotypes in the years 1975, 1976, 1977-'78.

[Biological effects of distamycin A]

In the present review are examined different biological effects of Distamycin A, an antibiotic produced by Streptomyces distallicus. This drug is moderately active on bacteria but it is strongly active on DNA viruses and on some Oncornaviruses, moreover it possesses antineoplastic and antimitotic activity at high doses at which it can result tossic and cause immunodepression.

Rubella virus hemagglutination with human and animal erythrocytes: effect of age and trypsinization

Sensitivity to rubella virus hemagglutination differs considerably with newborn as opposed to adult erythrocytes (RBC) in several animal species. In humans, cord RBC are 16 times more sensitive to hemagglutination, whereas hemagglutination titers with newborn RBC are 6 to 16 times higher in chickens, mice, and rabbits. This higher sensitivity is, however, short-lived, and adult RBC values are observed 7 days after birth in mice. Trypsinization has no effect on newborn RBC, but increases sensitivity of adult RBC to that of neonatal RBC and tends to diminish differences among individuals. On the other hand, trypsinization does not further enhance the very high sensitivity of pigeon, duck, and goose RBC or the low sensitivity of both newborn and adult guinea pig RBC. Human cord RBC proved suitable for use in hemagglutination-inhibition tests, since they gave titers comparable to those obtained with other types of RBC and offered some advantages: by comparison with animal RBC, they did not require adsorption to remove nonspecific agglutinins; by comparison with adult human RBC, they did not need trypsinization.

[Differences of capacity of human erythrocytes of newborn infants and adults and trypsin-treated erythrocytes to bind rubella virus hemagglutinin]

Rubella virus hemagglutinating (HA) antigen shows different titers against non treated, trypsin-modified and cord blood human erythrocytes. Trypsin-modified erythrocytes give titers eleven fold higher, and cord blood red cells sixteen fold higher than those seen with the non treated cells. These differences in sensitivity agree with a different ability to bind HA antigen: with an excess of antigen cord blood erythrocytes bind two, and trypsin-modified erythrocytes three times as much antigen was bound by non treated cells. The amount of bound antigen shows little or no dependence on 4 degrees or 37 degrees C temperatures.

The effect of pre-treatment of syngeneic mice with tumour cells cultured in vitro on the induction of a transplantable tumour

The pre-treatment with in vitro cultured mammary adenocarcinoma (ADK-1t) cells strongly protects syngeneic Balb/c mice against the challenge with the same non-cultured tumour cells. If the cultured cells were detached with sodium versenate, 50-60% protection was given, whereas if trypsin was used only 20-30% protection was achieved. That in vitro culture considerably reduces the oncogenic potential of ADK-1t cells was shown by the fact that very many more cultured than non-cultured cells were required to induce tumours.

[Effect of the cell dose on the development of 2 transplantable tumors in a syngeneic host]

The effects of different cell dose inoculation of plasmocitoma MOPC-315 and ADK-1t in Balb/c syngeneic mice are discussed in this work. Inoculated cell dose and neoplasia percent incidence have been noticed to be closely related, but unexpectedly two doses exist for each tumour, a comparatively small one and a definitely larger one, which cause nearly the same percent incidence. This paradox phenomenon is discussed also with reference to other researchers remarkers.

Enhancement of tumour growth by pretreatment with tumoral cells adsorbed by poly i:c deae-dextran complex in syngeneic mice

Pretreatment of balb/c mice with ADK-1t cells adsorbed with Poly I:C DEAE- dx complex was found to enhance tumour growth as measured after challenge with non adsorbed ADK-1t cells. This results contrasts strongly with the increased tumour resistance previously observed when Poly I:C alone was used for adsorption. Some reasons are suggested for this striking difference.

[Hemagglutinating activity of various viruses on trypsinized erythrocytes]

Mengo, Vesicular stomatitis and Semliki forest viruses titered with trypsin modified mouse, goose, pigeon and human erythrocytes show HA titers 2-32 fold higher than with the same untreated cells.

[Aspecific inhibitors of rubella virus hemagglutination in normal and thyroidectomized rats]

Thyroidectomized rats show alterations in serum lipoprotein distribution with an high increase of low density lipoproteins (LDL): however inhibitors titre was the same both in control and in treated animals. Also removal of nonspecific inhibitors by precipitation with heparin-MnCl2 or D.S. CaCl2 methods did not show differences between control and treated animals.

[Effects of a synthetic peptide on the cytotoxic activity of the lymphocytes of animals with tumors]

The influence of Peptichemio on cell immunity was studied by examining the in vitro response of lymphocytes from animals bearing a tumour treated with the drug. Two experimental tumours with different features, i.e. an adenocarcinoma (ADK-1t) and a plasmacytoma (MOPC-460) were used. The former was more sensitive to Peptichemio. The colony inhibition test was used for the ADK-1t and 51Cr release for the MOPC-460 owing to the fact that two different methods of culture in vitro were employed. In the case of ADK-1t 4mg/Kg Peptichemio given on alternate days, five times beginning from the 3rd day after challenge, was followed by 40% reduction in lymphocyte toxicity by comparison with the controls. In the case of MOPC-460, on the other hand, no significant lymphocyte toxicity was observed, even in the controls. It was concluded that, in both cases, Peptichemio at this dose does not interfere with the immunity response of the host to any great extent, and is selectively active against neoplastic cells.

[Inhibition of rubella virus hemagglutination by dextran sulfates of high molecular weight]

High molecular weight Destran-sulphates greatly affect rubella virus hemoagglutinin. The inhibition is to be related to the molecular weight. D.S. with p.m. 1,2 X 10(4) show no inhibitory activity, while D.S. 5 X 10(5), and furthermore D.S. p.m. 2 X 10(6) inhibit hemoagglutination. The inhibition appears to be related not to the effect of D.S. on red cells but to the interaction of D.S. with rubella hemoagglutinin. The entity of inhibition is a function of the concentration of D.S. in the test specimen: as much more intense is the former, as much higher is the latter. It is to be noticed however that also relatively little concentrations show to possess a clear inhibitory activity. Concentrations of 0,006 mg/ml and 0 ,05 mg/ml of D.S. (p.m. 2 X 10(6)) cause a lost of hemoagglutinin titre, showing respectively two and four twofold diluition lower titres than controls.

[Action of a synthetic peptide on some syngeneic tumors]

The protective effect of intraperitoneal Peptichemio at different doses in a population of syngeneic mice with four experimental tumours is described. The drug is much used in oncology en account of its low toxicity and is both alkylating and antimetabolic. It was found more effective against plasmacytomas and less so against a spontaneous adenocarcinoma (ADK lt) Activity was noted at the lowest dose employed (4 mg/Kg five times on alternate days), which had no more than a slight immunodepressor effect and was unattended by sideeffects, as well as at the highest dose (10 mg/Kg). Evaluation of mean diameters and survival in the experimental animals and in the controls made it clear that the drug possessed almost general effectiveness, in addition to being most active against plasmacytomas.

[The immune response to cryotherapy of prostatic carcinoma]

The Authors look for the theoric process by which an immunological response can occur after cryosurgery of prostate carcinoma. The theories about the development of this hypothetic response are explained and thoroughly considered also in the light of personal results.