کیوان زندی

Leptospirosis is a globally important zoonotic disease with worldwide prevalence, caused by spirochetes from the genus Leptospira. Diagnosis based on serology requires testing of acute and convalescent sera. PCR techniques have high sensitivity and specificity for early diagnosis of this disease.

Sera of all (49 cases) livestock breeders of the Helleh River area and 200 domestic animals were collected after 7-10 days from the outbreak of haemorrhagic fever in domestic animals of the Helleh River area in 2004, following torrential rains and flooded water occurrence in this area, and were tested by PCR based on 16srRNA gene. PCR method was used for 60 sera of livestock breeders from the surroundings villages as the normal control group. The human sera were tested for anti-Leptospiral antibodies using ELISA methods for Leptospira IgM.

Leptospiral genomes were detected in 16 cases (32.65%) of livestock breeders and 19 cases (9.5 %) of domestic animals by PCR. But, in the normal control group, Leptospiral genomes were not detected. A number of 15 cases of livestock breeders of Helleh River area were positive for IgM-ELISA. Among the PCR positive cases (16 persons), 10 cases were negative and 6 cases were positive for IgM-ELISA.

The haemorrhagic fever in domestic animals of the Helleh River area in Bushehr is recognized to be Leptospirosis. The 16S rRNA-based PCR method can recognize pathogenic Leptospira in clinical samples and provides early decisive diagnosis possibility of active infection.

By considering the daily increase in drug resistance of various viruses, novel antiviral compounds extracted from natural resources – due to their fewer side effects, had always been important to researchers. In the present study, we investigated antiviral activity of the hot water extract of a green seaweed, Caulerpa sertularioides, collected from coastal water of Bushehr in the Persian Gulf, against Herpes Simplex Virus Type 1 (HSV-1).

The hot water extract of a green seaweed, Caulerpa sertularioides was sterilized by autoclave and filtration methods. After determining its cytotoxic concentration 50 (CC50) value, the effect of the extract on the inhibition of HSV-1 replication was examined in Vero cell culture.

The extract showed antiviral activity against HSV-1 in both attachment and entry of virus to the Vero cells and also on post attachment stages of virus replication. Inhibitory concentration 50 (IC50) values of the autoclaved extract were 81µg/ml and 126 µg/ml for attachment and post attachment stages, respectively. IC50 values of the filtered extract were 73 µg/ml and 104 µg/ml for attachment and post attachment stages, respectively. CC50 values for autoclaved and filtered extracts were 3140 µg/ml and 3095 µg/ml, respectively.

The hot water extract of Caulerpa sertularioides of the Persian Gulf had antiviral effect against HSV-1.

Mumps virus is the cause of a contagious disease mostly seen in children and young adults.Immunoglobulin G protects individuals from reinfection. Because of the broad range of incubation time in various individuals, the presence of the virus in saliva before the appearance of clinical symptoms and infection of many individuals without symptoms makes the control of the transmission of the disease difficult. Therefore, vaccination is the best way to control the disease and spread of the viral agent. In addition, laboratory methods with a high sensitivity are needed to determine vaccine efficiency and to identify susceptible groups and infected individuals.

In this research, we used the viral neutralization test (VNT) and ELISA to determine IgG titers. First, the VNT was performed for 400 cord blood samples from which, 91.7% were detected to be positive. A vero cell line was infected with Hushino strain of mumps virus. By the hemadsorption test, the virus propagation in the infected cell line was confirmed. Later, the cultured virus was concentrated by PEG 6000, then purified by sucrose gradient and the amount of the protein was determined. The purified virus was coated on the micotiter plates and an indirect ELISA was performed. We used the VNT as a golden standard to determine the efficiency of our designed ELISA method.

The results demonstrated that the two methods have a good correlation. The sensitivity and specificity of our ELISA system was 100% and 97% respectively. Thus, our ELISA technique is a reliable method to determine mumps virus antibody titer.