Apex Exponents for Polymer--Probe Interactions

We consider self-avoiding polymers attached to the tip of an impenetrable probe. The scaling exponents $\gamma_1$ and $\gamma_2$, characterizing the number of configurations for the attachment of the polymer by one end, or at its midpoint, vary continuously with the tip's angle. These apex exponents are calculated analytically by $\epsilon$-expansion, and numerically by simulations in three dimensions. We find that when the polymer can move through the attachment point, it typically slides to one end; the apex exponents quantify the entropic barrier to threading the eye of the probe

Evaluation of in vitro antiviral activity of a brown alga (Cystoseira myrica) from the Persian Gulf against herpes simplex virus type 1

The hot water extract of a brown marine alga, Cystoseira myrica, from the Persian Gulf was evaluated as an antiviral compound against KOS strain of HSV-1 in cell culture. The extract exhibited antiviralactivity against herpes simplex virus type 1 (HSV-1) not only during absorption of virus to the cells, but also on post attachment stages of virus replication. The water extract of C. myrica was sterilized byfiltration and autoclaving, respectively. The IC50 for filtered extract was 99 ìg/ml and the IC50 for autoclaved extract was 125 ìg/ml. Based on resulted selectivity index (SI) values of the extracts, whichwere 33.4 and 28.2 for filtered and autoclaved extracts, respectively, we found that the antiviral compound(s) in the water extract of C. myrica to be heat stable. Also, the SI values for inhibition of thepost attachment stages of HSV-1 replication were 23.1 and 21.7 for filtered and autoclaved extracts, respectively. The IC50 in this phase of study were 143 and 162 ìg/ml for filtered and autoclaved extracts,respectively. Therefore, C. myrica could be a good candidate as a natural source for anti-HSV-1 compound(s) isolation

Antiviral activity of Aloe vera against herpes simplex virus type 2: An in vitro study

In this study we tested the antiviral activity of a crude hot glycerine extract of Aloe vera gel which was grown in Bushehr (Southwest of Iran) against HSV-2 replication in Vero cell line. The extract showedantiviral activity against HSV-2 not only before attachment and entry of virus to the Vero cells but also on post attachment stages of virus replication. The IC50 before attachment and entry of virus to the cellsis 428 ìg/ml and the CC50 value which is the cytotoxicity of the extract for Vero cells is 3238 ìg/ml, while the calculated selectivity index (SI) is 7.56. Also, IC50 of extract on post attachment stages of replicationis 536 ìg/ml and the SI value for inhibition of the post attachment stages of HSV-2 replication is 6.04. Therefore, compounds of Aloe vera from Bushehr could be a good candidate as a natural source for antiviral drug development against HSV-2

Life cycle information from a Wisconsin poplation of Porcellio spinicoris, the dark-headed isopod

Detailed life cycle information is lacking for Wisconsin terrestrial isopod crustaceans. We measured head-widths of a local population of Porcellio spinicornis and compiled data on size frequencies, sex ratio and gravidity. Females were larger and formed a majority of the population. Gravidity showed a definite seasonal pattern; percentages of gravid females ranged from zero in March and April to near 80% in late May and early June

Implementation and modeling of a femtosecond laser-activated streak camera

8 June 2017) A laser-activated streak camera was built to measure the duration of femtosecond electron pulses. The streak velocity of the device is 1.89 mrad/ps, which corresponds to a sensitivity of 34.9 fs/pixels. The streak camera also measures changes in the relative time of arrival between the laser and electron pulses with a resolution of 70 fs RMS. A full circuit analysis of the structure is presented to describe the streaking field and the general behavior of the device. We have developed a general mathematical model to analyze the streaked images. The model provides an accurate method to extract the pulse duration based on the changes of the electron beam profile when the streaking field is applied

Anticancer activity of Sargassum oligocystum water extract against human cancer cell lines

Background and Objectives: Antitumor drug resistance and side effects of antitumor compounds are the most common problems in medicine. Therefore, finding new antitumor agents with low side effects could be interesting. This study was designed to assay antitumor activity of the extract from brown alga Sargassum oligocystum, gathered from Persian Gulf seashore, against K562 and Daudi human cancer cell lines. Materials and Methods: The research was performed as an in vitro study. The effect of the alga extract on proliferation of cell lines were measured by two methods: MTT assay and trypan blue exclusion test. Results and Conclusion: The most effective antitumor activity has been shown at concentrations 500 μg/ml and 400 μg/ml of the alga extract against Daudi and K562 cell lines, respectively. The results showed that the extracts of brown alga Sargassum oligocystum have remarkable antitumor activity against K562 and Daudi cell lines. It is justified to be suggested for further research such as algal extract fractionation and purification and in vivo studies in order to formulate natural compounds with antitumor activities

Isolation of a 60 kDa protein with in vitro anticancer activity against human cancer cell lines from the purple fluid of the Persian Gulf sea hare, Aplysia dactylomela

Sea hares have greatly attracted the interest of all those investigating chemical defense substances. Most of these substances are low molecular weight compounds derived from algal diets. In vitroanticancer effect of a 60 kDa protein isolated from the purple fluid of Aplysia dactylomela on four human cancer cell lines was investigated in this study. A 60 kDa protein was purified from secreted purple fluid of A. dactylomela, a sea hare from Persian Gulf. The protein purification procedure consisted basically of ammonium sulfate precipitation, ion exchange chromatography using DEAE– Sepharose and ultra-filtration method. In vitro antiproliferative and cytotoxic activity of the protein ofinterest were evaluated on L929, K562, HL60 and NB4 human cancer cell lines. The antiproliferative and cytotxic effects of 60 kDa protein on human cancer cell lines were measured by MTT assay. Resultsshowed that the 60 kDa protein of the purple fluid of A. dactylomela exhibited the antiproliferative effect on human cancer cell lines, especially on NB4 cell line. It was maximally active at 0.5 – 1.5 ìg/ml on NB4 cell line. Interestingly, the protein did not show significant cytotoxic effects

In vitro antitumor activity of Gracilaria corticata (a red alga) against Jurkat and molt-4 human cancer cell lines

Gracilaria corticata is a red alga which can be collected from many sea coasts around the world such as China, India, Persian Gulf, etc. The Persian Gulf is a unique marine habitat infested with diverse seaweeds. The aim of the present study is to explore anticancer potential of the crude extracts from G. corticata which was collected from the Bushehr coast (South west of Iran). Here, different concentration of the aqueous extract from G. corticata was tested for probable antitumoral activity on Jurkat and molt- 4 human lymphoblastic leukemic cell lines. The cells were treated by different concentration of algal extract and the number of viable cells was determined by trypan blue. Also, cytotoxicity of the extract was evaluated by methyl thiazolyl tetrazolium (MTT) assay. The results showed that 9.336 and 9.726 μg/μl of algal extract were the most effective concentrations against Jurkat and molt-4 cells, respectively. The water crude extract of red alga G. corticata had significant anticancer activity and it might be a good candidate for further investigations in order to develop a natural compound as an anticancer agent which can be used for the production of potential anticancer drug and novel pharmaceutical leads.Key words: Gracilaria corticata, anticancer, Jurkat, molt-4

Antiviral activity of Holothuria sp. a sea cucumber against herpes simplex virus type 1 (HSV-1)

BACKGROUND: Finding the new bioactive compounds with antiviral activity from the natural resources are in interest of many drug discovery scientists. Sea cucumber is among the marine organisms a traditional food item in Asia with different applications in traditional medicine. METHODS: In current study, a cold water extract of the Holothuria sp, one type Persian Gulf’s sea cucumber was evaluated for its antiviral effects against KOS strain of Herpes Simplex Virus tyoe 1 (HSV-1) in cell culture. The half maximal inhibitory concentration (IC50) values were calculated for anti-adsorption activity and intracellular antiviral activity of the crude extract separately. RESULTS: The extract exhibited antiviral activity not only against the virus adsorption to the cells, but also on virus intracellular replication.The CC50 for sea cucumber extract was 32.57 mg/ml. The IC50 values for the inhibition of the virus adsorption to the cells and virus intracellular replication were 120.2 and 189.9 μg/ml respectively. Selectivity index (SI) value for anti-adsorption activity was 189 while that value for the extract’s intracellular antiviral activity was 172. CONCLUSIONS: The results showed that Holothuria sp, water extract has remarkable antiviral effect against HSV-1 in cell culture and it is crucial to investigate the mechanism(s) of action of extract. Moreover, identification of the effective compound(s) within the extract would be necessary for future studies towards developing the new natural antiviral agent against HSV-1

Molecular epidemiology of hepatitis C virus genotypes in Bushehr province, Iran

Background and Objectives: Molecular epidemiology of hepatitis C virus (HCV) is very important for the treatment of hepatitis C infection. The aim of this study was to determine the distribution of HCV genotypes in Bushehr province (South West of Iran). Materials and Methods: A total of 100 patients who were detected as positive for HCV antibody (by using ELISA method and RIBA test) referred to Arya Virology Laboratory between 2007-2009 in order to molecular diagnosis and furthermore virus genotyping. After detection of HCV, RNA genotyping of virus was done by using genotype specific primers. Results: Genotype 1a was found in 49% of the patients and genotype 3a was found in 40% of the patients and 1b in 5% of patients, while the genotype of the virus could not be identified in 5% of the patients. Finally, in 1% of patients coinfection due to 1a-3a genotypes was identified. Conclusion: The dominant genotype of HCV in Bushehr province, Iran, was determined as 1a.with acute hepatitis C ultimately develop chronic infection1. Only a minority of cases of acute HCV recover completely, with spontaneous virus eradication. In most cases the acute infection progresses to chronicity. Chronic HCV infection is defined as an infection that persists for more than 6 months, with or without clinical manifestations of hepatic or extrahepatic disease. Chronic type of this infection can cause cirrhosis, liver failure, and liver cancer. HCV infection is a global health problem and it is estimated that 200 million people of the world population are infected5. The global spread of chronic HCV infection coincided with the widespread use of transfused blood and blood products and with the expansion of intravenous drug use but decreased prior to the wide implementation of anti-HCV screening6. There are at least six major genotypes designated by Arabic numerals and more than 50 subtypes of HCV identified by lower case letters. The different genotypes have different geographic distributions1,4. Genotype determination of HCV is one of the most important factors in order to prediction of the viral persistency, pathogenicity and resistancy to antivirals7. The success and the treatment period of interferon and ribavirin seems to be related to the genotype of virus8. Furthermore, HCV genotyping is a useful tool to determine its molecular epidemiology, as they are indicative of transmission route of infection9,10. There is no published data about the distribution of HCV genotypes from Bushehr province (South West of Iran). Prevalence of HCV genotypes in Bushehr is an issue that is not sufficiently investigated and there is a need, therefore, to study this in detail