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91.
92.
Blum K Chen TJ Meshkin B Waite RL Downs BW Blum SH Mengucci JF Arcuri V Braverman ER Palomo T 《Medical hypotheses》2007,69(5):1054-1060
There are common genetic mechanisms responsible for both drug effects and subsequent seeking behavior. In 1996, we coined the term Reward Deficiency Syndrome (RDS). Past and current treatment of substance seeking behavior, a subtype of Reward Deficiency Syndrome (RDS), is considered by most to be inadequate. Recently, we evaluated a complex named Synaptamine [Haveos (SG8839R)]. The main difference with an older studied variant and the latest variant is the inclusion of a proprietary form of Rhodiola rosea, a known catechol-O-methyl-transferase inhibitor (COMT) to potentially enhance the activity of presynaptic released dopamine. In this regard, based on the current literature we hypothesize that manipulation of catechol-O-methyl-transferase (COMT) activity to influence the attenuation of substance seeking behavior, is dependent upon gene polymorphisms. In this regard we hypothesize that carrying the LL genotype with low COMT activity should as theorized, increase the reward induced by substance-induced dopamine release and may indeed increase the propensity to type 1 alcoholism and possibly other drugs that activate the dopaminergic system. Thus when alcohol is present in low COMT LL genotype, increasing COMT activity, not inhibiting it should assist in the reduction of social consumption or abuse. Alternatively, under physiological conditions (no psychoactive substances present (e.g. alcohol) carrying the DRD2 A1 allele with associated low D2 receptors should, as theorized, increase craving behavior because of a low or hypodopaminergic state causing the individual to seek out substances that increase the release of dopamine for subsequent activation of unbound D2 sites in the nucleus accumbens. Thus, in the absence of alcohol or other psychoactive drugs (dopamine releasers), especially during recovery or rehabilitation, decreasing, not increasing COMT activity, should result in enhanced synaptic dopamine as physiologically released, thereby proliferating D2 receptors while reducing stress, increasing well-being, reducing craving behavior and preventing relapse. Based on this hypothesis, we believe that adding the COMT inhibitor R. rosea (as Rhodimin) to our amino-acid and chromium combination in DUI offenders and other illegal drug-related crimes, increases the potential for more targeted neurochemical rebalancing and enhanced relapse prevention. Finally, we hypothesize that these data coupled together provide evidence that the combination of enkephalinase inhibition, neurotransmitter precursor loading, brain tryptophan enhancing and COMT inhibition as well as DNA analysis of the individual's genome, may be useful as an adjunct to therapy when used in outpatient recovery, specifically to assist in reducing craving behavior and preventing relapse. 相似文献
93.
Tomic K Mladinov D Batelja-Vuletic L Spajic B Mijic A Tomas D Belicza M Kruslin B 《Pathology, research and practice》2007,203(9):647-652
The aim of this study was to analyze morphometric parameters of renal arteries (longest diameter and tunica media thickness) in patients with renal cell carcinoma (RCC), to look into their relationship to tumor necrosis and to compare them with morphometric parameters recorded in a control group. We analyzed archival cases of RCC diagnosed in 2003 that also contained routinely sampled specimens of distal segments of renal artery. The control group consisted of specimens from both renal arteries obtained from 16 patients at routine autopsy during 2004-2005. Autopsy, as well as further histological analysis, did not disclose any malignant disease in the control group. Morphometric analysis of diameter and thickness of the renal artery tunica media was performed using Issa 3.1 software (Vamstek 2002, Zagreb, Croatia). The comparison of tunica media thickness showed that renal arteries from RCC cases were significantly thicker compared to distal parts of renal arteries in the control group (p=0.0002). Although renal artery samples from cases with necrotic tumor areas were thicker than those without tumor necrosis, the difference was not statistically significant. It is concluded that significantly thicker tunica media characterizes renal arteries in the group of patients with RCC when compared with the control group. 相似文献
94.
OBJECTIVES: The study objectives were: (a) to evaluate knowledge about osteoporosis and to identify its correlates among women > or =40 years of age attending outpatient centers; (b) to compare the level of knowledge between women already receiving treatment for osteoporosis and first-time attendees. METHODS: A cross-sectional survey was conducted with women recruited from nine outpatient centres in the Czech Republic. The women were divided into two subgroups: patients who have already been diagnosed with osteoporosis (osteopenia) and who are receiving treatment for the disease (OS group); first-time attendees who have been referred for the assessment of osteoporosis (comparison group). The patient's knowledge of osteoporosis was assessed using the Osteoporosis Questionnaire (OPQ) developed by Pande et al. [Pande KC, Takats D, Kanis JA, Edwards V, Slade P, McCloskey EV. Development of a questionnaire (OPQ) to assess patient's knowledge about osteoporosis. Maturitas 2000;37:75-81]. RESULTS: A total of 474 women (median age 63 years) were studied (306 in the OS group, 168 in the comparison group). Knowledge scores based on OPQ (median) were 7 and 6 points in the OS and comparison groups, respectively. When adjusted for age, the statistics showed better knowledge patients in the OS group (P=0.019). In both the OS and comparison groups, knowledge was found to be correlated positively with education (P<0.001) and experience of hormone replacement therapy (HRT) (P<0.001) and negatively with age (P<0.001). Knowledge was higher among women with better health status in the OS group. CONCLUSION: Knowledge about osteoporosis among Czech women aged > or =40 years and attending outpatient centers is relatively poor. To improve it, special attention should be paid to elderly women, those who have not used HRT, poorly educated women and those treated with several drugs. 相似文献
95.
Nichols KJ Tronco GG Tomas MB Kunjummen BD Siripun L Rini JN Palestro CJ 《Medical physics》2007,34(12):4792-4797
This investigation tested the hypothesis that visual analysis of iteratively reconstructed tomograms by ordered subset expectation maximization (OSEM) provides the highest accuracy for localizing parathyroid lesions using 99mTc-sestamibi SPECT data. From an Institutional Review Board approved retrospective review of 531 patients evaluated for parathyroid localization, image characteristics were determined for 85 99mTc-sestamibi SPECT studies originally read as equivocal (EQ). Seventy-two plexiglas phantoms using cylindrical simulated lesions were acquired for a clinically realistic range of counts (mean simulated lesion counts of 75 +/- 50 counts/pixel) and target-to-background (T:B) ratios (range = 2.0 to 8.0) to determine an optimal filter for OSEM. Two experienced nuclear physicians graded simulated lesions, blinded to whether chambers contained radioactivity or plain water, and two observers used the same scale to read all phantom and clinical SPECT studies, blinded to pathology findings and clinical information. For phantom data and all clinical data, T : B analyses were not statistically different for OSEM versus FB, but visual readings were significantly more accurate than T : B (88 +/- 6% versus 68 +/- 6%, p = 0.001) for OSEM processing, and OSEM was significantly more accurate than FB for visual readings (88 +/- 6% versus 58 +/- 6%, p < 0.0001). These data suggest that visual analysis of iteratively reconstructed MIBI tomograms should be incorporated into imaging protocols performed to localize parathyroid lesions. 相似文献
96.
97.
Klawitter V Morales P Bustamante D Gomez-Urquijo S Hökfelt T Herrera-Marschitz M 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,180(1):139-152
The potential neuroprotection of nicotinamide on the consequences of perinatal asphyxia was investigated with triple organotypic
cultures. Perinatal asphyxia was induced in vivo by immersing foetuses-containing uterine horns removed from ready-to-deliver
rats into a water bath for 20 min. Sibling caesarean-delivered pups were used as controls. Three days later tissue from substantia
nigra, neostriatum and neocortex was dissected and placed on a coverslip. After a month, the cultures were processed for immunocytochemistry
and phenotyped with markers against the NMDA receptor subunit NR1, tyrosine hydroxylase (TH), or neuronal nitric oxide synthase
(nNOS). Some cultures were analysed for cell viability. Nicotinamide (0.8 mmol/kg, i.p.) or saline was administered to asphyxia-exposed
and caesarean-delivered control pups 24, 48 and 72 h after birth. Perinatal asphyxia produced a decrease of cell viability
in substantia nigra, but not in neostriatum or neocortex. Immunocytochemistry confirmed the vulnerability of the substantia
nigra, demonstrating that there was a significant decrease in the number of NR1 and TH-positive (+) cells/mm2, as well as a decrease in the length of TH+ processes, suggesting neurite atrophy. In control cultures, many nNOS+ cells were seen, with different features, regional distribution and cell body sizes. Following perinatal asphyxia, there
was an increase in the number of nNOS+ cells/mm2 in substantia nigra, versus a decrease in neostriatum including reduced neurite length, and no apparent changes in neocortex.
The main effect of nicotinamide was seen in the neostriatum, preventing the asphyxia-induced decrease in the number of nNOS+ cells and neurite length. Nicotinamide also prevented the effect of perinatal asphyxia on TH-positive neurite length. The
present results support the idea that nicotinamide can prevent the effects produced by a sustained energy-failure condition,
as occurring during perinatal asphyxia.
The contribution of VK and PM has been equally relevant. 相似文献
98.
99.
Hao Wang Per Sikora Carolin Rutgersson Magnus Lindh Tomas Brodin Berndt Björlenius D.G. Joakim Larsson Heléne Norder 《International journal of hygiene and environmental health》2018,221(3):479-488
Sewage contains a mixed ecosystem of diverse sets of microorganisms, including human pathogenic viruses. Little is known about how conventional as well as advanced treatments of sewage, such as ozonation, reduce the environmental spread of viruses. Analyses for viruses were therefore conducted for three weeks in influent, after conventional treatment, after additional ozonation, and after passing an open dam system at a full-scale treatment plant in Knivsta, Sweden. Viruses were concentrated by adsorption to a positively charged filter, from which they were eluted and pelleted by ultracentrifugation, with a recovery of about 10%. Ion Torrent sequencing was used to analyze influent, leading to the identification of at least 327 viral species, most of which belonged to 25 families with some having unclear classification. Real-time PCR was used to test for 21 human-related viruses in inlet, conventionally treated, and ozone-treated sewage and outlet waters. The viruses identified in influent and further analyzed were adenovirus, norovirus, sapovirus, parechovirus, hepatitis E virus, astrovirus, pecovirus, picobirnavirus, parvovirus, and gokushovirus. Conventional treatment reduced viral concentrations by one to four log10, with the exception of adenovirus and parvovirus, for which the removal was less efficient. Ozone treatment led to a further reduction by one to two log10, but less for adenovirus. This study showed that the amount of all viruses was reduced by conventional sewage treatment. Further ozonation reduced the amounts of several viruses to undetectable levels, indicating that this is a promising technique for reducing the transmission of many pathogenic human viruses. 相似文献
100.
The anti-migraine drug sumatriptan often induces unpleasant somatosensory side effects, including a dislike of being touched. With a double-blind cross-over design, we studied the effects of sumatriptan and saline on perception (visual analogue scale) and cortical processing (functional magnetic resonance imaging) of tactile stimulation in healthy subjects. Soft brush stroking on the calf (n=6) was less pleasant (p<0.04) and evoked less activation of posterior insular cortex in the sumatriptan compared to the saline condition. Soft brushing activated pain processing regions (anterior insular, lateral orbitofrontal, and anterior cingulate cortices, and medial thalamus) only in the sumatriptan condition, whereas activation of somatosensory cortices was similar in both conditions. Soft brush stroking on the palm (n=6) was equally pleasant in both conditions. One possible mechanism for the activation of pain processing regions by brush stroking is sensitization of nociceptors by sumatriptan. Another possibility is inhibition of a recently discovered system of low-threshold unmyelinated tactile (CT) afferents that are present in hairy skin only, project to posterior insular cortex, and serve affective aspects of tactile sensation. An inhibition of impulse transmission in the CT system by sumatriptan could disinhibit nociceptive signalling and make light touch less pleasant. This latter alternative is consistent with the observed reduction in posterior insular cortex activation and the selective effects of stimulation on hairy compared to glabrous skin, which are not explained by the nociceptor sensitization account. 相似文献