Dissertation > Excellent graduate degree dissertation topics show

Constant Temperature of Morphine Hydrochloride on the Larvae of Lucilia Sericata and Its Forensic Significance

Author: QiLiLi
Tutor: LiZeMin
School: Hebei Medical University
Course: Pathogen Biology
Keywords: forensic entomology Forensic toxicologic entomology Lucilia sericata postmortem interval (PMI) cephalopharyngeal skeleton sclerotized area average optical density
CLC: D919
Type: Master's thesis
Year: 2011
Downloads: 2
Quote: 0
Read: Download Dissertation

Abstract

Objective: To study the growth and development of Lucilia sericata changes in morphine, experimental index to explore the regularity of change with time, so as to infer that the time interval between death and forensic toxicology insects provide a reference.Materials and Methods:Adult Lucilia sericata were collected from the outdoors. The experiment was done with offsprings of the third generation. Four domestic rabbits were prepared. The first one was used as a control and the other four were given morphine via ear vein according to the different dosages. All the rabbits were sacrificed by hitting the head quickly 30 minters later. The muscles from the four rabbits were take down and stored. They were marked with M0、M1、M2 and M3 .They were reared successively in biochemical culture boxes under the temperature of 28℃.The humidity, photoperiod and food supply were kept unchanged during the entire study. Form then on, eggs were placed onto each group of test muscle tissues to initiate the test colonies.When larvae were laid, 20 of them were randomly sampled from each group at 12h intervals until the beginning of the prepuparial stage. The 10 larvae were fixed in boiling water and then preserved in 70% alcohol mixed with glycerine. The other 10 were blotted up by the filter paper and then preserved in 70 degrees below zero.1 Preparation and observation of experimental specimenThe samples were taken out from the preserved solution and the liquid of surface was blotted up by the filter paper. Stick some holes on the abdomens of specimen with a pin, then fill them with 10% KOH to corrod their innards.24 hours later, press the larvae gently until they excreted the corroded tissues. Washed several times in clean water, it was taken apart that the section of scolex subsequent the 2nd section thoracic part under the stereomicroscope with anatomical scissors and scalpel. The specimens were dehydrated with alcohol from 30% to 100% gradually. After being transparent with dimethylbenzene, the specimens were observed and photographed. Finally the indexes including areas of different parts of cephalopharyngeal skeleton had been given by digital image processing equipment.2 Protein detectionRemove larvae specimens, in liquid nitrogen fully respectively after grinding, join 500μl PBS (pH7.4) solution, 12000rpm centrifugal 10min, the supernatant fluid namely for coarse extraction fluid.Take coarse extraction liquid, according to Bradford colorimetric method determined the OD value with 0.5 mg/ml, standard curve/ml bovine serum albumin production, use standard curve equation calculate sample protein content.Use analysis of variance (ANOVA) when made statistical analysis different indexes of cephalopharyngeal skeleton and protein concentration. Finally the data were statistically curved with Excel. Results:1 Morphological characteristics of cephalopharyngeal skeleton1.1 Under the same temperature condition, the color of each part of cephalopharyngeal skeleton becomed deeper than ever during the growth of larvae. The degree and range of chitinazation in cephalopharyngeal skeleton increased in accordance with the development. Lucilia cuprina larvae mouth bone without attached.1.2 In the same temperature, the area of mouth hook increased periodically. In M0, M1 and M2, M3 group, the mouth hook area in phased growth when replacement mouth hook area changing significant, especially in two, three ages when the most significant changes. When 12h, the larvae for minimal, mouth hook area between groups minimum mouth hook area has no obvious difference (P>0.05). M1 and M2, M3 group larvae 48h reaches maximum mouth hook area; M0 group larvae 60h reaches maximum. Each larva after maximum mouth hook area with the extension of time, the basic remain unchanged.The larvae mouth hook average light density ossification area and the changing trends and mouth hook area changing trend similar, but within 1-2 ages the change trend of the change of mouth hook is remarkable. When 12h each group mouth hook ossification area and average light density are the minimum; M0, M1 and M2, M3 reaches maximum time 72h, respectively 60h, 48h, 48h. With the increase of that drug concentration growth rate is increasing fast larva. In the four groups were in no corresponding hook, morphine hydrochloride each index of maximum impact. 1.3 When 12h larva pharynx bone area value is minimal, and minimum value there exist significant differences between (P<0.05), explain in the process of larva initially ingestion of its drug namely the influence; Along with the increase of drug concentrations increasing in swallow bone area.When 48h larva pharynx bone area value is the largest and M0<M1<M2< M3, pharynx bone area between maximum significantly (P<0.05), indicating that morphine hydrochloride the biggest pharynx increased larvae bone area.When 12h pharynx bone ossification area value is minimal, and M0<M1 <M2<M3, pharynx bone ossification area between the minimum value significantly (P<0.05); Larvae pharynx bone ossification area reaches maximum time 120h, respectively 120h, 96h, 84h, explain the development of bone ossification area swallow drug concentration increases with the increasing quickly, the higher the concentration of maximum ossification area shorter periods; Pharynx bone ossification area between maximum there exist significant differences (P<0.05), indicating that morphine hydrochloride increased larvae ossification largest area. The average optical density and the sclerotized area of pharyngeal sclerite grew gradually all the time and almost at the speed to the end of third instar.2 The change of protein contentFlies larvae of the protein content changes in an s-shaped type, is a process of continuous change. The protein content in first and second instars increasing rapidly, date in third instars are not obvious changes after. Four groups of protein content change trend: M0=M1<M2<M3, and maximum there exist significant differences between (P<0.05), indicating that the drug concentration increases with the protein content increased fly larvae, andmorphine hydrochloride larvae increased flies protein content maximum. Conclusions:1 Among the morphology indexes, the indexs of mouth hook kept growing periodically. Morphine hydrochloride not significantly affect the hook index.2 Larvae pharynx bone area and mouth hook area trend is same. The average optical density and the sclerotized area of pharyngeal sclerite grew gradually all the time and almost at the speed to the end of third instars.3 Morphine hydrochloride increases the maximum about pharynx bone area, pharynx bone ossification area, pharynx bones average light density; Under the influence of the drug, ossification area and average light density will be added fast with the increase of fertile drug concentration.4 Protein content of change is a continuous process with time in the early larva ingestion extend a growing trend, when reach maximum changes after not obvious. The drug concentration increases with the protein content increased fly larvae, and morphine hydrochloride larvae increased flies protein content maximum.

Constant Temperature of Morphine Hydrochloride on the Larvae of Lucilia Sericata and Its Forensic Significance

Abstract

Related Dissertations