Bioactivity profile of three types of seaweed as an antioxidant, UV-protection as sunscreen and their correlation activity

Seaweed is one of the marine algae that have antioxidant sources because it contains bioactive compounds such as carotenoids, phenol compounds and their derivatives, polysaccharide sulfate, and vitamins. Algae consist of three major groups namely brown algae (phaeophyta), red algae (rhodophyta), and green algae (chlorophyta). The purpose of this study was to determine the bioactivity profile of seaweed extract Eucheuma cottoni, Sargassum polycystum and Caulerpa racemosa so that it could be developed as a cosmetic raw material. The three types of seaweed were extracted by maceration and bioactivity testing was carried out as an antioxidant using the ABTS radical reduction method and bioactivity testing as UV-protection with the parameters of the percentage transmission of erythema, pigmentation and Sun Protective Factor (SPF). The results showed that C. racemosa extract provided a very strong antioxidant activity and was able to protect the skin from UV exposure with an SPF value that was categorized as ultra-protection. Antioxidant activity of the three types of seaweed is positively correlated to the protective effect based on the SPF value.

COMPARISON OF ELECTRON BEAM TRANSMISSION OF DIFFERENT ENERGIES WITH TWO DIFFERENT BLOCK MATERIALS AT DIFFERENT PLACEMENT POSITIONS WITHIN THE APPLICATOR

INTRODUCTION: Superficial tumors are treated with electron beams. Shielding blocks are used to conform to the shape of the tumor. These shielding blocks are usually kept at lower level of the applicator which is near the skin surface. The scattering property of electron may increase the surface dose which will increase with increasing electron energies. The purpose of this study is to compare electron beam transmission of different energies with two different block materials at different placement positions within the applicator. MATERIAL AND METHODS: Cerrobend alloy (50%bismuth, 26.7%lead, 13.3%tin and 10%cadmium) and 1mm thick lead sheets (94%lead, 6%alloy) in Varian Clinac2300C/D linear accelerator with electron energies 6,9,12,16 and 20MeVs using 10x10 applicator at 3 different holding levels was used. Measurements with RW3 Slab phantom (Water equivalent), PPC05 Parallel Plane Chamber, Dose 1 electrometer was done. The slab phantom 30x30x10 cm3 aligned with PPC05 Parallel Plane Chamber (at R85 of respective energies). Readings measured for open and block fields, for different thickness of shielding material, at different placement positions within the applicator. The percentage transmission calculated manually. RESULTS: Using electron energies 6,9,12,16, and 20MeVs respectively the transmission% were: with lead sheet 1mm thickness-2.48%,8.69%,16.05%, 28.03% and 39.50% at lower placement position, 1.19%,3.76%,7.75%,15% and 23.99% at centre placement and 0.96%,3.02%,6.15% and 20.27% for upper placement; with 2mm thickness-0.89%,1.62%,3.66%, 8.95% and 16.35% at lower level, 0.60%,1.28%,2.54%,5.74% and 10.72% at centre level and 0.57%,0.94%, 2.12%,4.85% and 9.22% at upper level; with 3mm thickness-0.80%,1.53%,2.88%,5.29% and 9.42% at lower position, 0.52%,1.25%,2.06%,4.03% and 7.36% at centre position and 0.51%, 0.90%,1.78%,3.66% and 6.43% at upper position; with 4mm thickness- 0.75%,1.40%, 2.71%,4.81% and 7.76% at lower level, 0.50%,1.18%,1.95%,3.68% and 6.31% at center level and 0.51%,0.80%, 1.70%,3.34% and 5.65% at upper level; with 5mm thickness-0.73%, 1.30%,2.57%,4.56% and 7.20% at lower level, 0.45%,1.06%,1.81%,3.48% and 5.68% at center level and 0.47%,0.79%,1.61%,3.13% and 5.24% at upper level. For Cerrobend material 5mm thickness, the transmission at lower level are 0.79%,1.50%,2.98%,5.58% and 10.39%, at center level are 0.52%,0.99%,2.09%,4.12% and 7.67% and at upper level are 0.49%,0.91%, 1.82%,3.75% and 6.90% for the energies 6,9,12,16 and 20 MeV’s respectively. CONCLUSION: There is not much difference in the transmission values at centre and upper levels so as to keep nearer the skin, the centre position in electron applicator may be optimum. Lead sheets can be used since easy to prepare especially for rectangular or square shapes.

Pathophysiology and Treatment of Hepatitis C Infection

The pathophysiology and treatment of hepatitis C infection, formerly known as non-A, non-B hepatitis, are discussed. The worldwide prevalence is approximately 1%. The majority of patients infected with hepatitis C virus will develop chronic infection, leading to cirrhosis in a significant percentage. Transmission of hepatitis C is primarily through parenteral routes. Those who use intravenous drugs or received blood transfusions prior to 1992 comprise the major risk groups for the infection. The progression of chronic hepatitis C infection is insidious with possible progression to an inflammatory hepatitis developing within 5–10 years, cirrhosis in 10–20 years, and hepatocellular carcinoma in 20–30 years. Combination therapy with interferon alpha-2b and ribavirin is currently the treatment of choice. Therapy for hepatitis C continues to evolve with newer forms of interferon and HCV antivirals under development.

Transmission of the California Tobacco Rattle Virus (CTRV) by Three Species of the Nematode Genus Trichodorus

The California tobacco rattle virus (CTRV), serologically related to the Dutch strains of TRV, was successfully transmitted by three species of the nematode genus Trichodorus Cobb, 1913. Trichodorus christiei Allen, 1957 (Riverside and Shafter isolates) and T. porosus Allen, 1957, were moderately good vectors when California Wonder pepper and Glurk tobacco, respectively, both poor hosts for the nematodes, were used as sources of virus and as bait plants. Trichodorus allius Jensen, 1963 was an excellent vector and was used in all experiments on nematode-virus interrelationships. Ten nematodes were sufficient to transmit CTRV to 100 percent of the bait plants, Nicotiana glutinosa, while one and five nematodes transmitted the virus to 60 and 80 percent of the bait plants, respectively. When Glurk tobacco (Nicotiana tabacum var. Xanthi-nc) was used, all the stages of T. allius transmitted the virus with almost equal efficiency. Ten nematodes of any stage, the three larval stages and the adult females, provided 100-percent transmission; five nematodes of any stage except third-stage larvae produced similar results. When single nematodes were used, percentage transmission was as follows; Adult females, 100, second-stage larvae, 50, fourth-stage larvae, 33.3; and third-stage larvae, 16.7. When 50 nematodes per pot were used, Trichodorus californicus Allen, 1957 did not transmit CTRV. Populations of T. allius became infective after feeding on virus-infected Glurk tobacco for 1 hour. Efficiency increased as the feeding time was increased up to 24 hours. An infective population transmitted CTRV within 1 hour after being added to the roots of a bait-plant, and efficiency of transmission increased up to 48 hours. Evidence for transovarial transmission and transtadial passage of the virus was not conclusive. Populations remamed infective for 20 weeks when kept at 20°C. without a host and 27 weeks when feeding on a virus-immune host. Virus was recovered directly from cut nematodes when their body contents were rubbed on leaves of cowpea, Vigna sinensis (Tomer) Savi.

HOST REACTIONS TO THREE STRAINS OF ASTER YELLOWS VIRUS FROM MANITOBA

One non-celery-infecting strain of aster yellows virus (NAYV) and two celery-infecting strains (CAYV-Z and CAYV) were isolated in Manitoba. Percentage transmission of the three strains of AYV to 13 plant species by single, infective male or female six-spotted leafhoppers (Macrosteles fascifrons (Stål)) given a 2-day inoculation feed varied with the host and virus strain. Head lettuce (Lactuca sativa var. capitata L.), and stinkweed (Thlaspi arvense L.) were superior to China aster (Callistephus chinensis Nees) as indicators of the proportion of infective leafhoppers. Acquisition of virus by vectors fed on the 13 plant species, as indicated by transmission to aster, differed according to strain and host. The differences between hosts in the percentages of plants infected with AYV was attributed to plant host – virus rather than the vector–virus relationships.There was no correlation between the susceptibility of a host and its value as a virus source. Head lettuce was the only one of the 13 plant species tested that was highly susceptible and from which all three strains of AYV could be readily acquired.

Simultaneous Determination of Calcium and Magnesium of Serum by a Single Chelometric Titration

Titration of a trichloracetic acid filtrate of serum with EDTA is carried out at pH 9.8 using an excess of Calmagite indicator. Successive photometric readings of percentage transmission, made with an EEL titrator, are plotted against the volume of EDTA added. There is very little change at first while calcium is being complexed; the reading then decreases rapidly while magnesium is being titrated, followed by a flattening of the curve at completion of the titration. Hence, two sharp "breaks" are obtained in the titration curve, the first corresponding to the amount of calcium and the second to the amount of magnesium.

THE SIX-SPOTTED LEAFHOPPER, MACROSTELES FASCIFRONS (STÅL.) AND ASTER YELLOWS IN MANITOBA

The six-spotted leafhopper overwintered in the egg stage only. Adults migrated into Manitoba in substantial numbers on strong south winds in mid-May. The migrant population reached a peak of about 80 leafhoppers per 100 sweeps in mid-June on cereals. There was a high mortality of migrants in late June and early July. The non-migrant population originated partly from overwintered eggs but mostly from eggs laid by migrants. New generation adults appeared in late June. Distinct broods were not apparent in the field because generations overlapped. The peak of population, about 400 leafhoppers per 100 sweeps, was reached about mid-August. Four generations were reared in a year. In general field collections the percentage of leafhoppers transmitting the aster yellow virus did not exceed 1 per cent. The percentage transmission was highest in the migrant population but dropped in July and August with the increase in local population. The rate of virus transmission was low in June and July but reached a peak in August in conjunction with the peak in population. Some weeds are a source of aster yellows virus. In Manitoba, early maturing crops generally escape severe aster yellows infection but it is often a problem on late crops.