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31.
This study evaluated the concentrations of nine heavy metals in muscle specimens of pike (Esox lucius Linnaeus, 1758) from four sites of southwest of the Caspian Sea: Shijan, Abkenar, Hendakhale and Siakeshim. The potential human health risks due to consumption of pike have been assessed by estimated average daily intake (EDI) and target hazard quotient (THQ) of metals. In particular, Cu, Zn, Cd, Pb, Hg, As, Ni, Co and Mn were quantified in the edible tissue of specimens by AAS determination. The average metal concentrations of Cu, Zn, Cd, Pb, Hg, As, Ni, Co and Mn measured in this study were 1.12?±?0.264, 5.37?±?0.702, 0.058?±?0.023, 0.20?±?0.035, 0.005?±?0.002, 0.17?±?0.047, 0.33?±?0.062, 0.28?±?0.034 and 0.20?±?0.035?μg/g w wt, respectively. Our results demonstrate the consumption of muscle of pike for adult and children as less than 1, hence residents of these regions will not be exposed to significant health risks.  相似文献   
32.
Two 1,3,5-trisubstituted aromatic scaffolds intended to serve as gamma-turn mimetics have been synthesized and incorporated in five pseudopeptide analogues of angiotensin II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe), replacing Val-Tyr-Ile, Val-Tyr, or Tyr-Ile. All the tested compounds exhibited nanomolar affinity for the AT2 receptor with the best compound (3) having a K(i) of 1.85 nM. Four pseudopeptides were AT2 selective, while one (5) also exhibited good affinity for the AT1 receptor (K(i) = 30.3 nM). This pseudopeptide exerted full agonistic activity in an AT2 receptor induced neurite outgrowth assay but displayed no agonistic effect in an AT1 receptor functional assay. Molecular modeling, using the program DISCOtech, showed that the high-affinity ligands could interact similarly with the AT2 receptor as other ligands with high affinity for this receptor. A tentative agonist model is proposed for AT2 receptor activation by angiotensin II analogues. We conclude that the 1,3,5-trisubstituted benzene rings can be conveniently prepared and are suitable as gamma-turn mimics.  相似文献   
33.

Background

Toxoplasmosis is a worldwide spread disease. The present study examined the prevalence of Toxoplasma gondii infection among animals of edible meat (cattle and sheep) in Chaharmahal va Bakhtiari Province (Southwest of Iran) in 2012. Furthermore, we attempted for the first time to identify this parasite from the meat products in the province.

Methods

The tongue, brain, femur muscle and liver of 50 sheep and 70 cattle as well as 50 samples of meat products were selected and collected to perform molecular survey using Nested-PCR method.

Results

Of the studied sheep, 38% were infected. The infection rate in the age groups under 1 year, 1-2 years, and more than 2 years was 25%, 35.29% and 52.94%, respectively. The infection rate in femur muscle, brain, liver and tongue was 28%, 32%, 30% and 16%, respectively. Of the studied cattle, 8.57% were infected. The infection rate in the age groups 1-2 years, 2-4 years, and more than 4 years was 3.7%, 9.09% and 14.28%, respectively. Sheep was infected 6 times more than cattle (OR = 6.53 CI = 2.374-18.005).The infection rate among samples of meat products was 12% (6 samples out of 50 samples).

Conclusion

Due to the high rate of this parasitic infection among the slaughtered animals as well as meat products in this region, the use of infected material can be one of the main risk factors of transmission of the parasite to humans.  相似文献   
34.
Abstract

MicroRNAs (miRs(, as short non-coding RNAs, regulate important biological processes and mainly are associated with regulation of gene expression. The miRs are beneficial targets for diagnosis of various disorders, particularly cancer, since their expression profile undergoes alterations in pathological conditions. The numerous drugs have been designed with the capability of targeting miRs for treating pathological conditions. On the other hand, the application of naturally occurring compounds has been increased due to their minimal side effects and valuable biological and therapeutic activities. Ginsenosides are able to act as anti-tumor agents via either increasing or decreasing the expression level of miRs. Ginsenosides affect the expression profile of miRNAs to induce their protective impacts. Angiogenesis as a key factor in the progression of cancer can be suppressed by ginsenosides which is mediated by miR regulation. The aim of this review is to shed some light on the protective and anti-tumor activities of ginsenosides mediated by miRNAs.  相似文献   
35.
The predominant metabolic pathway of gemcabene in humans is glucuronidation. The principal human UDP-glucuronosyltransferases (UGTs) involved in the glucuronidation of gemcabene were determined in this study. Glucuronidation of gemcabene was catalyzed by recombinant UGT1A3, recombinant UGT2B7, and recombinant UGT2B17, as well as by human liver microsomes (HLM). Gemcabene glucuronidation in recombinant UGTs and HLM followed non-Michaelis-Menten kinetics consistent with homotropic activation, but pharmacokinetics in humans were linear over the dose range tested (total plasma C(max), 0.06-0.88 mM). Gemcabene showed similar affinity (S(50)) for recombinant UGTs (0.92-1.45 mM) and HLM (1.37 mM). S-Flurbiprofen was identified as a more selective inhibitor of recombinant UGT2B7-catalyzed gemcabene glucuronidation (>23-fold lower IC(50)) when compared with recombinant UGT1A3- or recombinant UGT2B17-catalyzed gemcabene glucuronidation. The IC(50) for S-flurbiprofen inhibition of gemcabene glucuronidation was similar in HLM (60.6 microM) compared with recombinant UGT2B7 (27.4 microM), consistent with a major role for UGT2B7 in gemcabene glucuronidation in HLM. In addition, 5,6,7,3',4',5'-hexamethoxyflavone inhibited recombinant UGT1A3 and recombinant UGT2B17-catalyzed gemcabene glucuronidation (with 4-fold greater potency for recombinant UGT1A3) but did not inhibit gemcabene glucuronidation in HLM, suggesting that UGT1A3 and UGT2B17 do not contribute significantly to gemcabene glucuronidation. Reaction rates for gemcabene glucuronidation from a human liver bank correlated well (r(2)=0.722, P<0.0001; n=24) with rates of glucuronidation of the UGT2B7 probe substrate 3'-azido-3'-deoxythymidine. In conclusion, using the three independent experimental approaches typically used for cytochrome P450 reaction phenotyping, UGT2B7 is the major enzyme contributing to gemcabene glucuronidation in human liver microsomes.  相似文献   
36.
Structural and biochemical modifications of the myocardium (remodeling) occur during the development of left ventricular hypertrophy and acute myocardial infarction. An important part of this process of myocardial remodeling occurs in the interstitial compartment. The myocardial interstitium is composed mainly of fibrillar collagen. These changes are associated to modifications in ventricular function that could be deleterious and have clinical manifestations. Some salutory effects of the treatment of both conditions are related to modifications of the process of myocardial interstitial remodeling.  相似文献   
37.
Echinococcus tapeworms are parasites that infect dog species worldwide and occasionally are transmitted to humans. Infection occurs most commonly in persons who raise sheep or cattle, and who have contact with dogs. The tapeworm eggs are typically ingested during play with dogs or through consumption of garden vegetables or water contaminated by dog feces. The most common sites of tapeworm cyst formation within the body are the liver and lungs, although any internal organ or bone can be infected. The tapeworm infection is generally asymptomatic for 10 to 20 years, until the cyst grows large enough to cause problems. Untreated infection can be fatal. The possibility of this uncommon infection is most often considered when cysts are found on imaging studies of affected organs. Serologic testing has variable sensitivity, but it can be helpful. Surgical removal of cysts is the usual treatment, often with perioperative use of anthelmintic medication to prevent recurrence of disease caused by later growth of undetected daughter cysts.  相似文献   
38.
Annals of Biomedical Engineering - Retinal illnesses such as diabetic retinopathy (DR) are the main causes of vision loss. In the early recognition of eye diseases, the segmentation of blood...  相似文献   
39.
Inflammation Research - Among the countless endeavours made at elucidating the pathogenesis of COVID-19, those aimed at the histopathological alterations of type 2 alveolar epithelial cells (AT2)...  相似文献   
40.
Background: Pain is a common complaint among patients referring to the emergency department. This study aimed at comparing the effect of fentanyl and vitamin B12 to decrease the abdominal pain in patients who are addicted to oral opium.

Methods: This study conducted a double-blind randomized clinical trial on patients addicted to oral opium during a one-year period. The effects of fentanyl and vitamin B12 were compared for the relief of abdominal pain in such patients.

Results: The 136 patients studied had a mean age of 47.77 ± 13.6 years (mean ± SD). There was a significant difference in mean pain severity at 10, 15, 30, 45, 60, and 120 min (P < .05). The mean pain severity in the fentanyl group was significant at 30 min compared to the earlier times and showed a decreasing trend in pain severity (P < .05). This decreasing trend was observed up to 120 min for the fentanyl + vitamin B12 group, which showed a significant difference between each time and the time preceding it (P < .05).

Conclusions: The proper and permanent control of abdominal pain experienced by patients addicted to oral opium is essential. The combined use of fentanyl and vitamin B12 is effective in reaching this goal.  相似文献   

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