A systematic review of clinical applications of polymer gel dosimeters in radiotherapy

Abstract: Radiotherapy has rapidly improved because of the use of new equipment and techniques. Hence, the appeal for a feasible and accurate three-dimensional (3D) dosimetry system has increased. In this regard, gel dosimetry systems are accurate 3D dosimeters with high resolution. This systematic review evaluates the clinical applications of polymer gel dosimeters in radiotherapy. To find the clinical applications of polymer gel dosimeters in radiotherapy, a full systematic literature search was performed on the basis of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines in electronic databases up to January 31, 2017, with use of search-related terms in the titles and abstracts of articles. A total of 765 articles were screened in accordance with our inclusion and exclusion criteria. Eventually, 53 articles were included in the study. The findings show that most clinical applications of polymer gel dosimeters relate to external radiotherapy. Most of the gel dosimeters studied have acceptable dose accuracy as a 3D dosimeter with high resolution. It is difficult to judge which is the best polymer gel dosimeter to use in a clinical setting, because each gel dosimeter has advantages and limitations. For example, methacrylic acid–based gel dosimeters have high dose sensitivity and low toxicity, while their dose response is beam energy dependent; in contrast, N-isopropylacrylamide gel dosimeters have low dose resolution, but their sensitivity is lower and they are relatively toxic. Keywords: Polymer gel dosimetry Clinical application Radiotherapy Brachytherapy Neutron capture therap

Estimating growth parameters for Otolithes ruber in waters of Bushehr, Hormozgan and Sistan and Baluchestan Province, Southern Iran

Using length frequency of the Otolithes ruber collected in waters of three southern province of Iran, we estimated the fish growth parameters and monthly measured fork length of around 1000 fish caught using gill net with a mesh size of 6.5 centimeters in waters of this study area. The length infinity (L∞) in Bushehr, Hormozgan and Sistan and Baluchistan province was estimated as 58.5, 56, 59.5 centimeters, growth coefficient per year (K) as 0.48, 043, 0.32 and age at zero length (to) as -0.006, -0.002, -0.001 respectively. The relationship between length and weight of the fish in the three provinces determined. The parameters q, b and r (correlation coefficient) were 0.173, 2.868, 0.984 for Bushehr, 0.012, 2.962, 0.932 for Hormozgan and 0.056, 2.604, 0.921 for Sistan and Baluchestan province. We also evaluated the average length for the fish caught in different months and landing places. An ANOVA test showed a significant difference (P≤0.05) between the average lengths of the fish caught in different months

Assessing Pb, Ni and Zn accumulation in the tissues of Liza aurata in the south Caspian Sea

The liver, kidney, gill, ovary and muscle tissues of the caught Liza aurata have been sampled in spring 2002 in the southern Caspian Sea to assess their contamination with Pb, Ni and Zn using atomic absorption spectrophotometer method. We found the highest concentration of lead in the liver tissue (17.51 mg/kg), followed by gill (13.95 mg/kg); kidney (5.03 mg/kg) and ovary (4.91 mg/kg). The lowest concentration of lead was seen in muscle tissue (3.01 mg/kg) of Liza aurata. The highest accumulation of Ni and Zn were detected in ovary followed by liver, gill and kidney of the fish with a concentration of 6.23, 6.14, 5.71, and 2.98 mg/kg for Nickel and 647.28, 159.85, 75.71 and 65.42 mg/kg for Zinc. We observed the lowest concentration of Nickel (2.49 mg/kg) and Zinc (20.14 mg/kg) in the muscle tissue and also determined the highest contamination of the fish with these chemicals to be occurring in the southwest followed by south center and southeast Caspian Sea

Comparative study on gonad development in rainbow trout (Oncorhynchus mykiss) reared in fresh and brackish water in the Yazd Province

Rainbow trout (Oncorhylichus mikiss) weidting 200±5 grams were used in this study to compare their gonad development in fresh and brackish water in Yazd Province. The culture period lasted 140 days from October to March 2003 during which time the temperature 03.8+0.6), pH (8.18±0.12) and dissolved oxygen (6.2+0.11) of fresh and brackish water were kept nearly constant. The salinity of fresh and brackish water was 0.4 -0.5 and 14.3-14.7ppt respectively. The fish were fed common commercial trout food (Chineh GFT2) based on temperature and biomass. Histological studies indicated that the gonad development is accelerated in brackish water where the males mature two month eal her than those reared in freshwater. The gonadosomatic index (G51) also affirmed the gonad development (P<0.05)

Effects of hydrogen peroxide on fungal disinfection, hatch rate and larval deformities of rainbow trout (Oncorhynchus mykiss)

The hydrogen peroxide in concentrations of 500, 750 and 1000 mu l/l, malachite green with usual concentration (1.5mg/l) and natural control treatments were examined to evaluate the antifungal effects of the chemicals on Rainbow Trout eggs. Hydrogen peroxide and malachite green treatments were performed after 48 hours after fertilization in every other day, until 4 days before hatch, each time for 15 minutes. During experiments, water parameters were measured which were 8.05±0.55mg/l for dissolved oxygen, 8.8±2.2 ° C for temperature, 7.9±0.05 for pH, 132±20mg/l for total hardness, and E.C was 336±24 mu s/cm. The fungal infection was minimal in malachite green treatment and was significantly different with other treatments (P>0.05). No significant difference in deformities caused by the treatments were observed (P>0.05)

Study on the changes of some physiological factors during osmoregulation of juvenile Persian sturgeons (Acipenser persicus)

Experimental trials of acclimatization of juvenile Persian sturgeon, Acipenser persicus to different salinites of 0,5,10, 15ppt were studied. The juvenile Persian sturgeons in three weight classes (1.5, 3, 5g) have been transfered from freshwater to different concentrations of saline water. Na+, k+, Cl- concentrations of blood serum and the changes in the number and size of chloride cells were measured. Na+ concentration showed an imperceptible trend and K+ concentration had a decreasing one size of changed chloride cells in different salinities were 8.6-13±0.3 μm and their numbers were (25-65±3) in 5 pairs of fillaments. The results revealed that salinity tolerance was increased with the fish size. According to this study, there is a direct relation between the number and size of chloide cells and salinities and time exposure

Anatomical and histological study of ovary development stages of big-eye kilka (Clupeonella grimmi) in Babolsar Area, Iran

Biological and reproduction characteristics of female big-eye kilka (Clupeonella grimmi) including body weight, fork length, age, gonad development stages, gonad weight, ganado somatic ratio (GSR) were studied. We sampled 808 fish specimens from the Southern Caspian Sea, Babolsar Area during December 2002 to May 2003. Gonad development stages were assessed through tissue sectioning. Results revealed spawning peak to occur in early January. We also measured body weight as 8.88±0.08 grams, fork length as 1.03±0.26 mm, age as 3.610.03 years, gonad development stage as 3.67±0.03, gonad weight as 0.5±0.01 grams and ganado somatic ratio (GSR) as 5.39 ±0.1 in the specimens. Totally, five age classes, dominated by the 4+ years were distinguished while no 1+ year's age class was observed. The abundance of gonad developmental stages 2-5 was 18.19%, 14.60%, 48.89% and 18.32% respectively. Macroscopic (visual) and microscopic (tissue section) observations of oocyte revealed the same results for gonad development

Study of behavioral responses of crayfish (Astacus leptodactylus) to free amino acids

For many aquatic animals olfactory has an important role in food searching and intake. Amino acids are the large group of olfactory stimulants in feeding behavior of aquatic organism. The aim of the study was to determine the olfactory preference in crayfish (Astacus leptodactylus). Crayfish juveniles (6 to 8cm L) were exposed to 20 amino acids, and two positive and negative controls, in laboratory condition. Experiments were carried out in 6 replicates. In the qualitative evaluation of crayfishs responses, Aspargine and Sistine stimulated a significant and obvious feeding reaction. The quantitative evaluation confirmed the effect of Asparagine but showed weak response for sistine. Phenylalanine, threonine, tyrosine, methionine, and lysine promoted low positive response. The quantitative evaluation verified this result except for tyrosine and phenylalanine. Other amino acids didn’t show considerable attractive effects on feeding behavior. The quantitative evaluation confirming the results of pervious observation showed the well apparent response for glycine and thriptophan. The responses for aspartic acid, serine, acid glutamic and proline were sufficiently positive. According to the results asparagine could be considered as a suitable appellant for Astacus leptodactylus

Rapid, cost-effective, sensitive and quantitative detection of Acinetobacter baumannii from pneumonia patients

BACKGROUND AND OBJECTIVES: Pneumonia with Acinetobacter baumannii has a major therapeutic problem in health care settings. Decision to initiate correct antibiotic therapy requires rapid identification and quantification of organism. The aim of this study was to develop a rapid and sensitive method for direct detection of A. baumannii from respiratory specimens. MATERIALS AND METHODS: A Taqman real time PCR based on the sequence of bla(oxa-51) was designed and used for direct detection of A. baumannii from 361 respiratory specimens of patients with pneumonia. All specimens were checked by conventional bacteriology in parallel. RESULTS: The new real time PCR could detect less than 200 cfu per ml of bacteria in specimens. There was agreement between the results of real time PCR and culture (Kappa value 1.0, p value<0.001). The sensitivity, specificity and predictive values of real time PCR were 100%. The prevalence of A. baumannii in pneumonia patients was 10.53 % (n=38). Poly-microbial infections were detected in 65.71% of specimens. CONCLUSION: Acinetobacter baumannii is the third causative agent in nosocomial pneumonia after Pseudomonas aeroginosa (16%) and Staphylococcus aureus (13%) at Tehran hospitals. We recommend that 104 CFU be the threshold for definition of infection with A. baumannii using real time PCR

Population dynamics of the Spanish mackerel (Scomberomorus commerson) in coastal waters of Oman Sea

Length composition data of narrow-barred Spanish mackerel, Scomberomorus commerson (Lacepede 1800), landed between April 2002 to March 2004, were monthly used to estimate the growth, mortality and exploitation parameters of the stock. Maximum fork length and weight were 170 cm and 38 kg, respectively. Nonlinear least square fitting provided a complete set of von Bertalanffy growth estimates: L¥=178 cm (FL); K=0.28 and to= -0.36 years. The estimated value of total mortality based on length converted catch curve using these growth parameters is Z=0.95 year-I. Natural mortality based on growth parameters and mean environmental temperature (T=26.5°C) is M=0.36 year-1. Furthermore, the annual instantaneous fishing mortality rate of 0.59 year-1 was by far in excess of the precautionary target (Fopt=0.18 year-1) and limit (Flimit=0.24 year-1) biological reference points, indicating that the resource is heavily over-exploited and the management of this species should be implanted rapidly if they are to remain sustainable