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91.
Protective role of melatonin and retinol palmitate in oxidative stress and hyperlipidemic nephropathy induced by adriamycin in rats 总被引:2,自引:0,他引:2
Pedro Lopez Montilla Isaac Fiñana Túnez Carmen Muñoz de Agueda Felix Luna Gascón Juan Vicente López Soria 《Journal of pineal research》1998,25(2):86-93
Abstract: We have studied the effects of melatonin and retinol palmitate (RP) on the nephropathy and oxidative stress induced by a single and high dose of adriamycin (AD) in Wistar male rats. A dose of melatonin (75 μg/ kg/day) and a dose of RP (0.25 g oily solution/kg/day, sc) were injected 3 and 9 days before and after the administration of AD (25 mg/kg, i.p.), respectively. After the decapitation, samples were taken from the neck vascular trunk in order to determine the triglycerides, total cholesterol, phospholipids, HDL-cholesterol, total proteins, urea, lipoperoxides, and reduced glutathione (GSH). We estimated the lipoperoxide and glutathione (GSH) contents in renal homogenates, and the excretion of proteins in urine over a 24 hr period. The administration of AD caused significant increases in proteinuria and in the other parameters studied [lipids (triglycerides, total cholesterol, phospholipids, and HDL-cholesterol), nonprotein nitrogen compounds, and lipoperoxides]. AD increased the lipoperoxide content, but it decreased the GSH content in the kidney. Both melatonin and RP, although melatonin more significantly, decreased the intensity of the changes produced by the administration of AD alone. In fact, melatonin was quite efficient in reducing the formation of lipoperoxides, restoring renal GSH content and decreasing remarkably the severity of proteinuria. These results support the powerful antioxidant action of melatonin at renal level and a lower antioxidant action of retinol. Likewise, these data reinforce the hypothesis which supports the pathogenetic role and the close relation between the oxidative stress and the expression of the nephropathy induced by AD. However, in spite of this obvious antioxidant effect of melatonin in the kidney, additional studies are required to establish accurately the role of this pineal indole in the regulation and dynamics of the antioxidative defense enzyme system, which neutralizes the damaging effect of free radicals, both endogenous and exogenous, in this organ. 相似文献
92.
Rectal endometrial stromal sarcoma arising in endometriosis 总被引:3,自引:0,他引:3
Bosincu L Massarelli G Cossu Rocca P Isaac MA Nogales FF 《Diseases of the colon and rectum》2001,44(6):890-892
PURPOSE: Endometriosis of the rectovaginal septum can harbor different types of secondary tumors that may involve the rectal wall and protrude into its lumen, thus making diagnosis difficult. Extrauterine low-grade endometrial stromal sarcoma may rarely arise in endometriosis. The purpose of this article was to present the third case of this association. METHOD: This was a clinicopathologic study. RESULTS: A 42-year-old female presented with abdominal pain and fever. Laparotomy revealed a large pelvic mass involving the rectovaginal septum and the colonic wall and which protruded into the lumen forming endoluminal polypoid masses. Concomitant peritoneal nodules and a metastatic paracolic lymph node were also found. Histopathologically, primary endometriotic foci were found in close relationship with an endometrial stromal sarcoma which invaded the rectal wall. The female genital tract had no endometriotic lesions. The patient was treated by surgery and subsequent chemotherapy and was alive and well 20 months later. CONCLUSIONS: Endometriosis and its possible malignant changes should be taken into account in the differential endoscopic diagnosis of rectal masses in females. 相似文献
93.
A. R. Mayes C. L. Isaac J. S. Holdstock N. M. Hunkin D. Montaldi J. J. Downes 《Cognitive neuropsychology》2013,30(2):97-123
One kind of between-list and two kinds of within-list temporal order memory were examined in a patient with selective bilateral hippocampal lesions. This damage disrupted memory for all three kinds of temporal order memory, but left item and word pair recognition relatively intact. These findings are inconsistent with claims that (1) hippocampal lesions, like those of the medial temporal lobe (MTL) cortex, disrupt item and word pair recognition, and that (2) hippocampal lesions disrupt temporal order memory and item recognition to the same degree. Not only was word pair recognition intact in the patient, but further evidence indicates that her recognition of other associations between items of the same kind is also spared so retrieval of such associations cannot be sufficient to support within-list temporal order recognition. Rather, as other evidence indicates that the patient is impaired at recognition of associations between different kinds of information, within-list (and possibly between-list) temporal order memory may be impaired by hippocampal lesions because it critically depends on retrieving associations between different kinds of information. 相似文献
94.
Asaf Sol Ofir Ginesin Stella Chaushu Laila Karra Shunit Coppenhagen-Glazer Isaac Ginsburg Gilad Bachrach 《Infection and immunity》2013,81(10):3577-3585
Host defense peptides are immediate responders of the innate immunity that express antimicrobial, immunoregulatory, and wound-healing activities. Neutrophils are a major source for oral host defense peptides, and phagocytosis by neutrophils is a major mechanism for bacterial clearance in the gingival tissue. Dysfunction of or reduction in the numbers of neutrophils or deficiency in the LL-37 host defense peptide was each previously linked with proliferation of oral Aggregatibacter actinomycetemcomitans which resulted in an aggressive periodontal disease. Surprisingly, A. actinomycetemcomitans shows resistance to high concentrations of LL-37. In this study, we demonstrated that submicrocidal concentrations of LL-37 inhibit biofilm formation by A. actinomycetemcomitans and act as opsonins and agglutinins that greatly enhance its clearance by neutrophils and macrophages. Improved uptake of A. actinomycetemcomitans by neutrophils was mediated by their opsonization with LL-37. Enhanced phagocytosis and killing of A. actinomycetemcomitans by murine macrophage-like RAW 264.7 cells were dependent on their preagglutination by LL-37. Although A. actinomycetemcomitans is resistant to the bactericidal effect of LL-37, our results offer a rationale for the epidemiological association between LL-37 deficiency and the expansion of oral A. actinomycetemcomitans and indicate a possible therapeutic use of cationic peptides for host defense. 相似文献
95.
Christoph Hollnagel Heike Vallery Rainer Schädler Isaac Gómez-Lor López Lukas Jaeger Peter Wolf Robert Riener Laura Marchal-Crespo 《Medical & biological engineering & computing》2013,51(7):799-809
Pneumatics is one of the few actuation principles that can be used in an MR environment, since it can produce high forces without affecting imaging quality. However, pneumatic control is challenging, due to the air high compliance and cylinders non-linearities. Furthermore, the system’s properties may change for each subject. Here, we present novel control strategies that adapt to the subject’s individual anatomy and needs while performing accurate periodic gait-like movements with an MRI compatible pneumatically driven robot. In subject-passive mode, an iterative learning controller (ILC) was implemented to reduce the system’s periodic disturbances. To allow the subjects to intend the task by themselves, a zero-force controller minimized the interaction forces between subject and robot. To assist patients who may be too weak, an assist-as-needed controller that adapts the assistance based on online measurement of the subject’s performance was designed. The controllers were experimentally tested. The ILC successfully learned to reduce the variability and tracking errors. The zero-force controller allowed subjects to step in a transparent environment. The assist-as-needed controller adapted the assistance based on individual needs, while still challenged the subjects to perform the task. The presented controllers can provide accurate pneumatic control in MR environments to allow assessments of brain activation. 相似文献
96.
Satoshi Inoue Zhenyue Hao Andrew J. Elia David Cescon Lily Zhou Jennifer Silvester Bryan Snow Isaac S. Harris Masato Sasaki Wanda Y. Li Momoe Itsumi Kazuo Yamamoto Takeshi Ueda Carmen Dominguez-Brauer Chiara Gorrini Iok In Christine Chio Jillian Haight Annick You-Ten Susan McCracken Andrew Wakeham Danny Ghazarian Linda J.Z. Penn Gerry Melino Tak W. Mak 《Genes & development》2013,27(10):1101-1114
97.
Rafel Cirer-Sastre Alejandro Legaz-Arrese Francisco Corbi Isaac López-Laval Keith George Joaquín Reverter-Masia 《Journal of Science and Medicine in Sport》2021,24(2):116-121
ObjectivesTo determine the influence of maturational status on the release of cardiac troponin T (cTnT) induced by a bout of 30 min, high-intensity, continuous exercise.DesignQuasi-experimental, cross-sectional study.MethodsSeventy male, young, well trained swimmers (age range 7–18 years, training experience 1–11 years) were classified by maturational stages: Tanner stage I (n = 14), II (n = 15), III (n = 15), IV (n = 13), and V (n = 13). Participants underwent a distance-trial of 30 min continuous swimming, and cTnT was measured before, immediately after and 3 h after exercise. Changes in cTnT over time were compared among groups, and associated with exercise load.ResultsBasal cTnT was higher in Tanner-V (3.8–8.1 ng/L) compared with I (1.5–5.5 ng/L, p < 0.001), II (1.5–4.5 ng/L, p < 0.001) and III (1.5–6.8 ng/L, p = 0.003), and in IV (1.5–6.3 ng/L) compared with II (p = 0.036). Maximal elevations of cTnT from baseline were notable (p < 0.001) and comparable among maturational stages (p = 0.078). The upper reference limit for myocardial injury was exceeded in 35.7% of the participants, without differences among groups (p = 0.18). Baseline cTnT correlated with participant characteristics, and maximal cTnT elevations from baseline with exercise internal load (%HRpeak, rs = 0.34, p = 0.003; %HRmean, rs = 0.28, p = 0.02).ConclusionsMaturational status influences positively absolute pre- and post-exercise cTnT but not its elevation after a bout of 30 min, high-intensity, continuous exercise. 相似文献
98.
Adedayo O. Oduola Judith B. Olojede Isaac O. Oyewole Olubunmi A. Otubanjo Taiwo S. Awolola 《Parasitology research》2013,112(10):3433-3439
Mosquito samples were collected from rural and urban communities in three selected major towns in Southwestern Nigeria to determine the impact of urbanization on the diversity and abundance of Anopheles species associated with malaria transmission in human habitations. A total of ten Anopheles species were identified in the rural communities, while eight Anopheles species were identified in the urban communities. Out of the ten Anopheles species identified, only four species, Anopheles gambiae (Giles), Anopheles funestus (Giles), Anopheles moucheti (Evans), and Anopheles nili (Theobald), were established to be vectors of malaria occurring in greater than 50 % of the rural communities. Only A. gambiae occurred in all the urban communities, while the other three major vectors occurred in not more than 20 % of the urban communities. Margalef's and Shannon–Wiener indices showed that diversity and species richness were higher in the rural compared to the urban. Comprehensive information on malaria vector abundance and diversity in rapidly changing communities is an important tool in planning and implementing successful vector control programs. 相似文献
99.
Isaac J. Pence Christine M. OBrien Laura E. Masson Anita Mahadevan-Jansen 《Biomedical optics express》2021,12(2):852
In vivo Raman spectroscopy has been utilized for the non-invasive, non-destructive assessment of tissue pathophysiology for a variety of applications largely through the use of fiber optic probes to interface with samples of interest. Fiber optic probes can be designed to optimize the collection of Raman-scattered photons from application-dependent depths, and this critical consideration should be addressed when planning a study. Herein we investigate four distinct probe geometries for sensitivity to superficial and deep signals through a Monte Carlo model that incorporates Raman scattering and fluorescence. Experimental validation using biological tissues was performed to accurately recapitulate in vivo scenarios. Testing in biological tissues agreed with modeled results and revealed that microlens designs had slightly enhanced performance at shallow depths (< 1 mm), whereas all of the beampath-modified designs yielded more signal from deep within tissue. Simulation based on fluence maps generated using ray-tracing in the absence of optical scattering had drastically different results as a function of depth for each probe compared to the biological simulation. The contrast in simulation results between the non-scattering and biological tissue phantoms underscores the importance of considering the optical properties of a given application when designing a fiber optic probe. The model presented here can be easily extended for optimization of entirely novel probe designs prior to fabrication, reducing time and cost while improving data quality. 相似文献
100.
Isaac S. Gomes-Filho Julita Maria F. Coelho Samilly S. Miranda Simone S. Cruz Soraya C. Trindade Eneida M.M. Cerqueira Johelle S. Passos-Soares Maria da Conceição N. Costa Maria Isabel P. Vianna Ana Cláudia M.G. Figueiredo Alexandre Marcelo Hintz Amanda F. Coelho Luiz Carlos S. Passos Maurício L. Barreto Frank Scannapieco 《Journal of periodontology》2020,91(11):1444-1452