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1.
The effect of prenatal exposure to nicotine on nicotine-induced analgesia was studied in rats. The analgesic effect of a single dose of nicotine (1 mg/kg SC) was measured by the tail-flick technique, and two subsequent studies were carried out. In the first study, 7-month-old male rats, born to dams chronically treated with nicotine during pregnancy (NIC), exhibited prolonged nicotine-induced analgesia compared to matched controls. The second study was designed to explore whether rats prenatally exposed to nicotine (NIC rats) are born with an increased sensitivity to nicotine and whether there is any sex difference. The analgesic effect of nicotine was tested on control and NIC rats of both sexes once a month from 2 to 7 months of age. At an early age, male but not female NIC rats, exhibited shorter analgesic responses to nicotine than did the matched controls. With increasing age, however, the duration of nicotine analgesia began to be prolonged in NIC rats of both sexes. Significant differences between control and NIC rats were found at the age of 6 and 7 months, in both sexes. Thus, rats prenatally exposed to nicotine are not born with an increased sensitivity to the analgesic effect of a single dose of nicotine. This phenomenon develops later, during the course of life, independently of gender.  相似文献   
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3.

Aim

To describe the contribution of forensic anthropology to the recovery, analysis, and identification of victims from the 1991-1995 war in Croatia recovered in wells.

Methods

From 1996 to the present, human remains of a total of 61 individuals have been recovered from 13 wells. Six wells contained the remains of a single individual, one well contained the remains of 2 individuals, and 6 wells contained the remains 3 or more individuals. The majority of wells, containing 90.2% (55/61) of recovered individuals, were located within a 4 km radius of the Croatian-Serbian border.

Results

Forensic anthropologists re-individualized 26/61 (42.6%) individuals out of skeletonized and commingled remains, provided basic biological data on sex, age-at-death, and stature in all identifications (n = 37), as well as established positive identification by recognizing unique skeletal features (antemortem fractures and skeletal evidence of antemortem surgical interventions) in 3/37 (8.1%) cases. Trauma analyses carried out by forensic anthropologists contributed to the determination of the cause of death in 38/61 (62.3%) individuals and to the probable cause of death in an additional 18/61 (29.5%) individuals. The most frequent (27/38, 71.0%) type of trauma causing death in individuals recovered from wells was a single gunshot wound.

Conclusion

Forensic anthropologists, collaborating closely with forensic pathologists, forensic odontologists, forensic radiologists, criminologists, and molecular biologists contributed significantly to trauma analysis and identification of war victims recovered from wells.To address the need for identification of a large number of war victims in the 1991-1995 war in Croatia (1-8), in 1991 the Croatian Government formed a multidisciplinary team of forensic experts with a purpose of recovering, analyzing, and identifying human remains from individual and mass graves. This report describes the contribution of forensic anthropologists to this endeavor, specifically to the recovery, analysis, and identification of 61 individuals recovered from 13 wells in Croatia after the 1991-1995 war. The recovery and analysis of these individuals was, for a number of reasons, considerably more complicated than the recovery and analysis of individuals from other types of mass graves and individual graves (1).For obvious reasons, the recovery of human remains deposited in wells was more hazardous than the recovery of remains from other types of settings. Standard risks associated with this type of work are difficult access to the grave sites through mine fields, possible explosive devices hidden among the remains, and poorly preserved human remains. Besides this, recovery from wells was complicated by varying depth of the wells, problems pertaining to the draining off the wells, and – in the case of more dilapidated wells – the risk of collapse of the well walls. Trauma analyses and identification of the recovered individuals was hampered by problems such as poor preservation and commingling of the remains which were significantly more present in wells than in other types of settings (1).The multidisciplinary team assembled by the Croatian government to recover and identify missing individuals included forensic pathologists, forensic anthropologists, forensic odontologists, forensic radiologists, criminologists, and molecular biologists. Forensic anthropologists contributed to this team effort by: 1) helping in locating and recovering human remains; 2) separating and re-individualizing commingled remains; 3) interpreting skeletal evidence of trauma – identifying the presence of trauma, differentiating between antemortem, postmortem, and perimortem trauma, as well as establishing the sequence of perimortem traumas, when possible; and 4) adopting an osteo-biographical approach in order to supply not only basic data on the age-at-death, sex, and stature, but also on other biological characteristics potentially useful in the identification process. To facilitate this, a joint US-Croatian forensic anthropology project was developed. In this project, forensic anthropologists from the Croatian Academy of Sciences and Arts and forensic specialists from the Department of Forensic Medicine at the School of Medicine, University of Zagreb, together with forensic anthropologists from the Smithsonian Institution, Washington DC, USA and the University of Tennessee in Knoxville developed a forensic anthropology database. Data on sex, age-at-death, stature, cranial and postcranial metric characteristics, and osteological and dental features were collected, including the evidence on pathology, ante-mortem fractures, disease, and surgical interventions, as well as perimortem trauma and possible cause of death. The purpose of this database was 3-fold: 1) to identify a basic and standard set of measurements, observations, and definitions to ensure that data are comparable; 2) to store the data in a computer so that particular subsets can be quickly accessed, analyzed, and compared; and 3) to provide up-to-date discriminant formulae for determining sex, stature, and other traits useful for comparative research and forensic analysis. The data gathered so far have already been proved useful for calculating discriminant functions for determining sex from fragmentary and complete Croatian femora (3), estimating male stature from the maximum lengths of the humerus, femur, and tibia (9), as well as determining craniometric relationships between Americans (Caucasians), Croatians, and Bosnians (10).  相似文献   
4.
As part of our OPENTOX project, we evaluated the incidence and mass concentrations of multiclass pesticide residues in 23 river/stream water samples collected in urban and agricultural areas of northwest Croatia at various points of the pesticide application season in 2015. The study included 16 compounds of five herbicide classes and seven compounds of three insecticide classes. Pesticide residues were accumulated from water by solid-phase extraction and analysed using high performance liquid chromatography with UV-diode array detection and/or gas chromatography-mass spectrometry. Herbicide residues were more common than the insecticide ones, and, as expected, they peaked in the middle of the application season. Metolachlor showed the highest concentrations and was found in 91 % of all samples, followed by terbuthylazine, found in 70 % of the samples. The highest total mass concentration of detected pesticides was measured in the water samples of the Krapina (3992 ng/L) and Sutla (3455 ng/L) collected in rural areas with intensive agriculture. Our findings strongly speak in favour of continued monitoring of surface waters and possibly extending the list of priority water pollutants.KEY WORDS: degradation products, herbicides, insecticides, pesticide residues, river water, seasonal variations  相似文献   
5.
In this paper we report the autopsy findings of a 57 year old woman who died unexpectedly at home. She had been complaining of shortness of breath, episodes of dry coughing, and nausea. Her past medical and social history was unremarkable. She had no previous history of any viral or bacterial disease and no history of oncological disorders. Autopsy revealed multiple grayish-white nodular lesions in the pleura and epicardial fat and areas resembling fibrosis on the cut surface of the anterior and posterior wall of the left ventricle and interventricular septum. Histological examination of the lungs and heart revealed multiple well-formed noncaseating epithelioid cell granulomas with multinucleated giant cells. Death was attributed to myocardial ischemia due to vasculitis of intramural coronary artery branches associated with sarcoidosis. Sarcoidosis is a multisystemic disease of unknown etiology characterized by the formation of noncaseating epithelioid cell granulomas in the affected organs and tissues. The diagnosis of sarcoidosis in this case was established when other causes of granulomatous disease such as tuberculosis, berylliosis, hypersensitivity pneumonitis, and giant cell myocarditis had been reasonably excluded.  相似文献   
6.
We investigated, whether the effects on paclitaxel, docetaxel or their combinations on T-cell lymphomas in Sprague-Dawley/Cub rats were mainly caused by their different efficiency or combination of different mechanism of action, or limited by metabolic inactivation by P450 enzymes or drug efflux caused by P-glycoprotein (P-gp). Docetaxel most effectively prolonged the survival of rats and the time of lymphoma appearance, inhibited their intravital size and weight after sacrifice. Paclitaxel was poorly effective and combined administration had intermediate effects. Blood levels of both drugs were similar. Repeated administration of paclitaxel, but not docetaxel, decreased its area under concentration, but the effect disappeared 6h after dosing and was not sufficient to explain lower effects of paclitaxel. The faster metabolism of docetaxel than paclitaxel in vitro did not limit its higher efficiency and repeated administration of paclitaxel did not induce its metabolism to decrease its blood levels sufficiently. Likewise, undetectable expression of P-gp protein in tumours could not explain lower effects of paclitaxel, which is a better substrate of P-gp. Docetaxel was three-fold more effective than paclitaxel against P388D1 lymphoma cell line, used as a model of the T-cell lymphoma and combined action was dominated by the effects of docetaxel. Thus, docetaxel was effective against T-cell lymphomas and may be a potential anticancer drug in similar indications.  相似文献   
7.
Sodium butyrate or glucose deprivation induce a more differentiated phenotype in many cancer cells. The aim of this study was to determine whether the induction effect of butyrate and/or glucose deprivation is dependent, in some way, on the differentiation state of individual cell lines. Sodium butyrate enhanced alkaline phosphatase activity and induced formation of an ultrastructurally more differentiated phenotype in both HT29 and HT115 cell lines. Interestingly, the more invasive HT115 cells responded more strongly to butyrate treatment. On the other hand, the differentiation effect of glucose deprivation was much less prominent in the HT115 cell line in comparison with HT29 cells. Our data confirm the influence of the malignant potential of the cells on their response to treatment with differentiation and apoptosis-inducing agents. Butyrate treatment also enhanced the adhesiveness of HT115 cells. Since E-cadherin was not found in these cells, while the level of CEACAM1 was increased, it is obvious that the CEACAM1 molecules are involved in HT115 cell-cell adhesion.  相似文献   
8.
The paper describes the effect of glucocorticoid dexamethasone (DM) given intraperitoneally on the catalytic activity of butyrylcholinesterase (BuChE) measured in plasma, liver and white adipose tissue of rats of both sexes. Effects of DM on the concentration of plasma lipids and lipoproteins were also tested. Rats were given multiple (2 and 4) pharmacological doses (0.4 and 3.0 mg kg(-1) body mass) of DM. All animals were sacrificed 48 hours after the last dose. Administration of DM significantly decreased the catalytic activity of BuChE in plasma and liver of all treated groups regardless of sex. BuChE catalytic activity in white adipose tissue differed depending on the dose and frequency of administration. In contrast to liver where both doses caused significant BuChE inhibition, the lower DM dose did not inhibit BuChE activity in adipose tissue, and the inhibition achieved by the higher dose was not as strong as in liver. This result corroborates an earlier hypothesis that BuChE is also synthesized in the adipose tissue. DM significantly increased plasma concentrations of triglycerides, total cholesterol and high-density lipoprotein (HDL) cholesterol and decreased the low-density lipoprotein (LDL) cholesterol concentration. Neither positive correlation between BuChE and triglycerides nor negative correlation between BuChE and HDL was found. Changes in lipid profile during DM treatment were not sex- and time-dependent.  相似文献   
9.
Protoberberinium salts, i.e. berberine (I), palmatine (II) and jatrorrhizine (III) prepared from Mahonia aquifolium (Pursh) Nutt. belong to isoquinoline alkaloids possessing interesting biological activity (e.g. antibacterial, antimalarial, antitumor). The characteristic UV/Vis absorption band maxima of I-III iodide salts were found in regions 350 and 425 nm in dimethylsulfoxide (DMSO) and ethanol solvents, and were only negligibly influenced by substitution changes on the C-2 and C-3 positions. The fluorescence intensity of protoberberinium salts monitored in ethanol solutions was significantly lowered by iodide counter-ions, and decreased in the order berberine > palmatine > jatrorrhizine. EPR spectroscopy supplied evidence of the formation of super-oxide anion radicals and singlet oxygen upon irradiation of berberine in oxygenated DMSO solvent. The photochemical generation of O(2) (.-) and (1)O(2) in DMSO solutions of palmatine and jatrorrhizine was substantially lower, and probably reflected the replacement of a photolabile methylenedioxy group at C-2 and C-3 positions in the berberine molecule by two methoxy groups in palmatine, and methoxyl (C-2) and hydroxyl (C-3) substitution in jatrorrhizine. Additionally, the powder EPR spectra of protoberberinium iodides I-III measured at 290 K revealed the presence of single-line EPR signals (g(eff) = 2.0044), which were attributed to hydroperoxidic structures produced by the autoxidation process. The photochemical reactions of protoberbenium salts producing reactive oxygen species after UVA excitation should be integrated in biological activity investigations, as well as in their applications in skin disorder treatment.  相似文献   
10.
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