Assessment of perception of medical students in regard to links between tobacco or alcohol use and cancer.

BACKGROUND: The aim of this study was to assess cancer awareness among medical students in Saudi Arabia toward tobacco and alcohol use as risk factors. MATERIALS AND METHODS: A cross-sectional survey from October to December 2014, covering 1200 medical students, was performed. RESULTS: Of the total, 975 (81.25%) responded. The male to female ratio was 1.00:7.125. 96/975 (9.8%) had smoked tobacco in their lifetime, and 51/975 (5.23%) were alcoholic beverage consumers. On asking them whether tobacco smoking and alcohol consumption can cause cancer, only 4/975 (0.4%) and 14/975 (1.43%) answered no for smoking and alcohol, respectively. CONCLUSIONS: The prevalence of smoking and alcohol use is very low among medical students, which might be due to high female contribution besides social stigma. The prevalence of second-hand smoke (SHS) was found to be very high in Hail region.

Disinfection efficacy of sodium dichloroisocyanurate (NADCC) against common food-borne intestinal protozoa.

The present study was conducted to investigate the efficacy of sodium dichloroisocyanurate (NaDCC) on the infective stages of common food-borne intestinal protozoa; Entamoeba histolytica (E. histolytica), Giardia lamblia (G. lamblia), Cryptosporidium, Cyclospora and Microsporidia; beside its effect on raw green vegetables and fruits. Parasites, isolated from stool of patients with diarrhea or dysentery, were exposed to NaDCC solution (1g/l) for one and two hours. Disinfection effect of NaDCC was assessed by in-vitro viability, using trypan blue stain, and infectivity bioassay in laboratory animals as indicated by fecal and intestinal parasitic counts. Raw vegetables and fruits were dipped in NaDCC solution in the same concentration and exposure time as used for treatment of the parasites. Results revealed statistically significant reductions in viability and infectivity of all examined parasites indicating their susceptibility to NaDCC. Relative variations in susceptibility were revealed; E. histolytica and G. lamblia were most susceptible (100% reduction) followed by Microsporidia then Cryptospridium and Cyclospora. NaDCC did not affect the consistency, color, taste or flavor of raw green vegetables and fruits. The proved efficacy of NaDCC, in cheap and convenient dry tablet form, makes it a promising tool in decontaminating raw vegetables and fruits from food-borne protozoan parasites at household and restaurant levels as well as in catering and fresh produce industry. It is also recommended for disinfection of food preparation surfaces and equipment.

Immunization against trichinellosis using microwaved larvae of Trichinela spiralis.

The present study evaluated the effect of microwave irradiation on infective larvae of Trichinella spiralis (T. spiralis) by the ultrastructure changes of the microwaved larvae (ML) using scanning electron microscope (SEM). The ML tested the ability to immunize mice against a challenge infection with T. spiralis. For the optimal dose and the best route of immunization inducing protection against challenge infection, two doses were used; 300 & 600 ML as one or two-dose regimen, each dose was given orally and intraperitoneally (IP). SEM revealed tegumental damage of the ML in the form of distortion, loss of normal fold pattern and depressions or papillae protruded from their outer surface. After administration of the ML (orally or IP) to the non-infected control mice, neither adults nor larvae were detected in the intestines or muscles respectively. This indicated loss of larvae infectivity after exposure to the microwave irradiation. Also, a significant protection against challenge infection with T. spiralis was demonstrated in experimental mice immunized by ML, orally or IP. This was assessed by a statistically significant decrease in adult and muscle larval count, compared with the non-immunized infected control. Complete protection against both adults and larvae (100%) was achieved by IP injection of two doses of 600 ML, two weeks apart. The results suggested the feasible application of the microwave irradiation on meat for its decontamination from T. spiralis larvae. Such a method might be a promising a prophylaxis vaccine against trichinellosis in animals and/or humans.

The efficacy of antihelminthic compound; Clorsulon against experimental Schistosoma mansoni infection.

The efficacy of Clorsulon (CLS) against experimental schistosomiasis mansoni, using Praziquantel (PZQ) as a therapeutic control was evaluated. Swiss Albino mice were divided into infected non-treated control, PZQ-treated group given a single dose of 500 mg/kg four weeks post infection (PI), and infected mice treated with single, double, and triple doses of 5 mg/kg CLS per dose, one week apart starting from the 4th week PI. All animals were perfused for adults count. Parts of livers and intestines were examined for granulomata number and sizes. Pathological changes in hepatic parenchyma by H&E and Masson trichrome stains were also examined. Results revealed that a single treatment with PZQ caused a significant percentage reduction (%R) of worm load (92.68%), mean egg count in liver and intestine (91.20 & 94.01% respectively), and mean size of liver granulomata was reduced (92.06%). Regarding CLS, the worm burden was reduced proportionally with number of doses given; 87.80, 96.34 & 97.56% in single, double and triple exposures successively. Egg count in liver was decreased by 85.90, 97.01 & 96.23% respectively in treated mice. Number of intestinal granulomata was decreased by 85.28, 94.24 & 95.49% in a similar way. Size of hepatic granulomata was decreased by 89.02, 94.51 & 95.05% by 1, 2 & 3 doses consecutively. All parameters reflected non significant difference between 2 & 3 dose of CLS. The results were critically discussed.