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31.
J Saki AR Meamar H Oormazdi L Akhlaghi S Maraghi M Mohebali S Khademvatan E Razmjou 《Iranian Journal of Parasitology》2010,5(1):25-34
Background
Leishmaniasis is a protozoan disease cause by Leishmania genus. Anthroponotic and zoonotic cutaneous leishmaniasis are endemic in Iran. The aim of this study was to identify the causative agent of cutaneous leishmaniasis by mini-exon gene in five regions of Khuzestan Province, southwest of Iran.Methods
From 2007 to 2008 in this cross-sectional study, cutaneous samples were collected from patients referred to Health Centers and Hospitals of the Khuzestan Province for cutaneous leishmaniasis diagnosis and cultured in Novy-MacNeal-Nicolle (NNN) and RPMI 1640. The propagated promastigotes were harvested and Leishmania species of cutaneous leishmaniasis were identified by RFLP and DNA sequencing of the PCR generated fragments.Results
L. major and L. tropica were the causative agents of cutaneous leishmaniasis by predominantly of L. major species. The alignment of the mini-exon sequencing isolates with reported sequencing of L. major and L. tropica revealed 92%-99% identity.Conclusion
Our study showed that mini-exon PCR-RFLP was useful method to identify the causative species of cutaneous leishmaniasis. 相似文献32.
R Alexander A Kerby AA Aubdool AR Power S Grover C Gentry AD Grant 《British journal of pharmacology》2013,168(3):761-772
Background and Purpose
The Ca2+-permeable cation channel TRPV4 is activated by mechanical disturbance of the cell membrane and is implicated in mechanical hyperalgesia. Nerve growth factor (NGF) is increased during inflammation and causes mechanical hyperalgesia. 4α-phorbol 12,13-didecanoate (4αPDD) has been described as a selective TRPV4 agonist. We investigated NGF-induced hyperalgesia in TRPV4 wild-type (+/+) and knockout (–/–) mice, and the increases in [Ca2+]i produced by 4αPDD in cultured mouse dorsal root ganglia neurons following exposure to NGF.Experimental Approach
Withdrawal thresholds to heat, von Frey hairs and pressure were measured in mice before and after systemic administration of NGF. Changes in intracellular Ca2+ concentration were measured by ratiometric imaging with Fura-2 in cultured DRG and trigeminal ganglia (TG) neurons during perfusion of TRPV4 agonists.Key Results
Administration of NGF caused a significant sensitization to heat and von Frey stimuli in TRPV4 +/+ and –/– mice, but only TRPV4 +/+ mice showed sensitization to noxious pressure. 4αPDD stimulated a dose-dependent increase in [Ca2+]i in neurons from +/+ and –/– mice, with the proportion of responding neurons and magnitude of increase unaffected by the genotype. In contrast, the selective TRPV4 agonist GSK1016790A failed to stimulate an increase in intracellular Ca2+ in cultured neurons. Responses to 4αPDD were unaffected by pretreatment with NGF.Conclusions and Implications
TRPV4 contributes to mechanosensation in vivo, but there is little evidence for functional TRPV4 in cultured DRG and TG neurons. We conclude that 4αPDD activates these neurons independently of TRPV4, so it is not appropriate to refer to 4αPDD as a selective TRPV4 agonist. 相似文献33.
SMJ Mortazavi MA Mosleh-Shirazi AR Tavassoli M Taheri AR Mehdizadeh SAS Namazi A Jamali R Ghalandari S Bonyadi M Haghani M Shafie 《Dose-response》2013,11(2):281-292
The aim of this study was to investigate the effect of pre-irradiation with microwaves on the induction of radioadaptive response. In the 1st phase of the study, 110 male mice were divided into 8 groups. The animals in these groups were exposed/sham-exposed to microwave, low dose rate gamma or both for 5 days. On day six, the animals were exposed to a lethal dose (LD). In the 2nd phase, 30 male rats were divided into 2 groups of 15 animals. The 1st group received microwave exposure. The 2nd group (controls) received the same LD but there was no treatment before the LD. On day 5, all animals were whole-body irradiated with the LD. Statistically significant differences between the survival rate of the mice only exposed to lethal dose of gamma radiation before irradiation with a lethal dose of gamma radiation with those of the animals pre-exposed to either microwave (p=0.02), low dose rate gamma (p=0.001) or both of these physical adapting doses (p=0.003) were observed. Likewise, a statistically significant difference between survival rates of the rats in control and test groups was observed. Altogether, these experiments showed that exposure to microwave radiation may induce a significant survival adaptive response. 相似文献
34.
LINKED ARTICLES
This is a rebuttal by the authors (Green et al., pp. 1523–1536 of this issue) to a commentary by Parrott, pp. 1518–1520 of this issue. To view the article by Green et al. visit http://dx.doi.org/10.1111/j.1476-5381.2011.01819.x. To view the commentary by Parrott visit http://dx.doi.org/10.1111/j.1476-5381.2012.01941.xWe thank Prof Parrott (Parrott 2012) for his interest in our review (Green et al., 2012). Our main aim was to discuss the problems that arise in interpreting data obtained when administering 3,4-methylenedioxymethamphetamine (MDMA) to experimental animals in terms of possible clinical consequences and vice versa, not to disparage the evidence that Ecstasy is neurotoxic in humans. We presented evidence that the pharmacokinetics of MDMA in rats and primates are fundamentally different from the pharmacokinetics of the drug in humans. Because the plasma half-life of the drug in rats is 10 times shorter than in humans, the acute adverse events in rats may be minimal compared with those in humans, and this includes body temperature and endocrine changes. Conversely, the rapid metabolism of the drug in rats to form neurotoxic metabolites may result in more severe long-term effects in that species than those that may occur in humans.We had no intention of suggesting that there was no evidence for some recreational Ecstasy users presenting with evidence of 5-HT neurotoxicity, albeit it is clear from the literature that some of this evidence remains open to several interpretations. What we did claim was that pure 3,4-methylenedioxymethamphetamine (MDMA) taken alone was unlikely to cause 5-HT neurotoxicity in man. Here we must emphasize the term MDMA, as it is crucial to our discussion. Parrott, in contrast, uses the term ‘Ecstasy/MDMA’ several times when discussing neurotoxicity (Parrott, 2012). This association of Ecstasy with MDMA is one of the major problems of translation that we addressed. The Ecstasy tablet that most recreational users buy and ingest is not necessarily MDMA. Indeed, in many cases, it clearly is not. The tablet is often adulterated with other compounds, and one investigation identified no less than 14 substances other than MDMA in Ecstasy tablets, which users nevertheless presumably believed contained only MDMA (Vogels et al., 2009). Many of the adulterants identified were also psychoactive and included compounds structurally related to MDMA such as 3,4-methylenedioxyethylamphetamine and 2-methylamino-1-(3,4-methylenedioxyphenyl)butane, which have poorly researched pharmacology and toxicology. In addition, most recreational users of Ecstasy also knowingly ingest other psychoactive compounds such as alcohol and cannabis. Alcohol, for example, alters the pharmacokinetics of MDMA (Hamida et al., 2009). While, as Parrott states, clinical studies have attempted to allow for these confounding factors in any examination of the physical and psychological effects of MDMA in humans, such analysis is always limited not only by the other compounds the evaluators are unaware of, but also drugs perhaps not even considered to be relevant by the user and therefore not disclosed. It is unlikely that coffee and ‘energy drinks’ such as Red Bull are always disclosed, but there is now good preclinical evidence that caffeine, which incidentally has also been found as an adulterant in Ecstasy tablets, enhances both the hyperthermia and neurotoxicity induced in rats by MDMA (Camarasa et al., 2006; Vanattou-Saïfoudine et al., 2010). And this brings us to the crux of the problem and weakness of all the clinical data cited by Parrott (2012). A basic tenet of all good clinical pharmacology is accurate knowledge of the doses administered, frequency of administration and any confounding factors such as other drugs being consumed. None of these data are available with any precision in the clinical studies quoted. Of course one has some indication as to dose (although as Vogels et al., (2009) reported, the dose contained in illicitly obtained tablets is highly variable) and frequency of drug ingestion, but this information is generally obtained from the user whose recall is likely to be limited or who decides to obfuscate. Crucially, the information can never take into account the problem of drug tablet adulteration. The fact that hair or urine samples detect MDMA merely shows the user has consumed the drug, not how much or when or what other drugs were taken concurrently.We never suggested that MDMA exposure was not going to be associated with physical or psychological change. However such changes are not necessarily associated with long-term neurotoxic damage. We have shown that long-term behavioural effects can occur in rats both with and without 5-HT neurotoxicity (Fone et al., 2002; Bull et al., 2003; Rodsiri et al., 2011). It is interesting that Parrott approvingly quotes the Verheyden et al. (2003) study in support of his contention that neurotoxic damage has occurred. Because this study noted that the majority of persons reporting chronic psychiatric problems reported ‘improved mental health’ after quitting the drug, this surely allows us to conclude that the drug had produced subacute changes rather than any that could be associated with long-term neurotoxic damage.A further limitation to any clinical study is that one cannot perform prospective studies with the aim of investigating whether long-term neurotoxic events occur, so weaknesses arise with regard to any psychological abnormalities observed. Are persons with high risk of psychiatric problems more likely to misuse the drug, or does the drug induce changes in high-risk individuals? If high risk also happened to be associated with 5-HT abnormalities in the brains, then any conclusion that MDMA has induced neurotoxicity is spurious.We most certainly did not suggest that MDMA acted as a neurotoxin only under conditions of severe hyperthermia as is stated by Parrot in his sixth paragraph (Parrott, 2012). We have been involved in many studies on the effects of MDMA on body temperature in rats (see Docherty and Green, 2010) including one that demonstrated that neurotoxicity can occur in the absence of hyperthermia (O''Shea et al., 1998) and another that showed that hyperthermia worsens neurotoxic damage (Green et al., 2004). In our review, what we did propose was that because of the very different pharmacokinetics of MDMA in rats and humans, it is probable that humans would suffer serious or fatal adverse events at plasma levels below those likely to be required to induce 5-HT neurotoxicity.We emphasize again that we are not denying the clinical observations reviewed by Parrott, but conclude that the effects seen cannot be ascribed solely to the effects of MDMA, as he seems to be proposing. We also repeat our contention that MDMA in combination with other drugs may induce neurotoxicity and this could be said to be supported by the clinical studies quoted by Parrott.Finally, we can but assume that Parrott concurs with our principal conclusion that ‘the doses currently being used to investigate the possible therapeutic benefits of MDMA are unlikely to produce any severe acute or importantly any long-term neurotoxic damage in the human brain’ as he used such a dose (100 mg or approximately 1.4 mg·kg −1) in one of his recent studies in human volunteers (Parrott et al., 2011). 相似文献35.
Neoplastic and preneoplastic lesions induced by melamine in rat urothelium are modulated by dietary polyunsaturated fatty acids 总被引:6,自引:0,他引:6
D.C. Cremonezzi M.P. Daz M.A. Valentich A.R. Eynard 《Food and chemical toxicology》2004,42(12):1999-2007
The modulatory effects of polyunsaturated fatty acids (PUFA) on urinary tract tumorigenesis of 275 Wistar rats were evaluated by treating animals with the tumorigenic agent melamine. Rats were fed with formulae containing 6% of 4 varieties of fats: fish oil enriched in n-3 PUFA (FO), corn oil enriched in n-6 (CO), olein containing mainly n-9 oleic acid (O), and 98% stearic acid (SA), the latter two being essential (EFA)-deficient inducers. Two commercially fed control groups with (CM) and without (C) melamine were used. Animals were autopsied at 22–25 and at 36–40 weeks. Hepatic fatty acids showed that O and SA groups were EFA-deficient. Simple well differentiated hyperplasias were significantly higher in the FO lot, whereas dysplasia was increased in the CO, O and SA lots. Most of the animals fed for 36–40 weeks with the three latter formulae developed the more severe lesions. Increased urothelial proliferation was more frequent in EFA-deficient rats. The apoptosis/mitosis ratio was higher in O, SA and CO fed animals with respect to FO and chow ones. Results show that dietary PUFA modulate differentially both normal and pre-neoplastic urothelial proliferation induced by melamine. FO, rich in n-3 fatty acids, showed a strong protective effect. 相似文献
36.
Muñoz SE Piegari M Guzmán CA Eynard AR 《Nutrition (Burbank, Los Angeles County, Calif.)》1999,15(3):208-212
The modulating effect of dietary enrichment in mistol seed oil (MO) containing 25% of alpha-linolenic acid (ALA), evening primrose oil (EPO) enriched in gamma-linolenic acid (GLA) and corn oil (CO) as sources of omega-6 and omega-9 fatty acids on the growth parameters of one transplantable mammary tumor were compared. Mice fed on different lipid formulae were inoculated with a mammary gland adenocarcinoma and different growth development tumor parameters were recorded. Results showed that corn oil feeding slowed down most of the tumor growth parameters, as did the EPO diet. MO also showed antitumor activity. Olein feeding, which induces an essential fatty acid deficiency (EFAD), increased the incidence and the multiplicity of metastases when compared with the controls. It may be concluded that a diet enriched in omega-6 fatty acids did not behave as a tumor promoter in this mammary gland tumor model. The antitumor activities of EPO and MO are corroborated in present experiments, suggesting that both oils may be of value in nutritional approaches of mammary gland tumor therapies. In addition, present data add further experimental proof about the proposed protumorigenic proneness induced by the EFAD state. 相似文献
37.
自1994年以来,我院采用改良的尿道拖人术治疗外伤性后尿道狭窄22例,取得满意疗效,现报道如下。l临床资料本组病例均为男性,为严重车祸伤或高处跌伤致骨盆骨折所致,年龄则一46岁,平均35岁。临床症状有尿道四溢血、尿摊留、腹胀、肛周青紫肿胀,有休克者2例,合并直肠损伤2例,磅眈破裂6例。术中发现前列腺尖游离者4例。所有病例不能将导尿管插入膀跳,而均行单纯“耻骨上膀胜造疾术”,有膀脱破裂者行“膀脱破裂修补术”,有直肠损伤者,行“乙状结肠造疫术”。患者于术后3-6个月来院行尿道重建术。术前常规尿道造影,显示膜部尿道狭… 相似文献
38.
Background
Linguatula serrata, one of the parasitic zoonoses, inhabits the canine respiratory system (final hosts). The objective of this study was to determine the prevalence rate of L. serrata nymphs in mesenteric lymph nodes (MLNs) of cattle and buffaloes (intermediate hosts) that were processed in the Ahvaz, Iran abattoir.Methods
During November 2010 to March 2011, 223 animals (119 cattle and 104 buffaloes), in different sex and three age groups (<2, 2–< 3 and 3-> 3 years old) were sampled randomly at Ahvaz abattoir. Up to 35 grams of their mesenteric lymph nodes were examined separately for nymphal stages of L. serrata by digesting the samples with acid- pepsin method, collected the nymphs and counted under stereomicroscope.Results
Overall 37(16.6%) of 223 animals were infected with L. serrata nymphs in their mesenteric lymph nodes. Prevalence of the infection in cattle and buffaloes were 16.8% and 16.3% respectively. The number of collected nymphs of MLNs was ranged from 1 to 16. No significant differences were seen in the infection rates between males and females (sexes) and age groups in the cattle and buffaloes (P <0.05).Conclusion
Linguatula serrata has an active life cycle in the studied area and a zoonotic potential for transmission between animal and human. Avoiding use of raw MLNs to dogs can help reduce the infection. 相似文献39.
40.