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51.
52.

Background

On the basis of results of our previous investigations on 90Y-DTPA-rituximab and in order to fulfil national demands to radioimmunoconjugates for radioscintigraphy and radioimmunotherapy of Non-Hodgkin’s Lymphoma (NHL), preparation and radiolabeling of a lyophilized formulation (kit) of DOTA-rituximab with 111In and 90Y was investigated.

Methods

111In and 90Y with high radiochemical and radionuclide purity were prepared by 112Cd (p,2n)111In nuclear reaction and a locally developed 90Sr/90Y generator, respectively. DOTA-rituximab immunoconjugates were prepared by the reaction of solutions of p-SCN-Bz-DOTA and rituximab in carbonate buffer (pH = 9.5) and the number of DOTA per molecule of conjugates were determined by transchelation reaction between DOTA and arsenaso yttrium(III) complex. DOTA-rituximab immunoconjugates were labeled with 111In and 90Y and radioimmunoconjugates were checked for radiochemical purity by chromatography methods and for immunoreactivity by cell-binding assay using Raji cell line. The stability of radiolabeled conjugate with the approximate number of 7 DOTA molecules per one rituximab molecule which was prepared in moderate yield and showed moderate immunoreactivity, compared to two other prepared radioimmunoconjugates, was determined at different time intervals and against EDTA and human serum by chromatography methods and reducing SDS-polyacrylamide gel electrophoresis, respectively. The biodistribution of the selected radioimmunoconjugate in rats was determined by measurement of the radioactivity of different organs after sacrificing the animals by ether asphyxiation.

Results

The radioimmunoconjugate with approximate DOTA/rituximab molar ratio of 7 showed stability after 24 h at room temperature, after 96 h at 4°C, as the lyophilized formulation after six months storage and against EDTA and human serum. This radioimmunoconjugate had a biodistribution profile similar to that of 90Y-ibritumomab, which is approved by FDA for radioimmunotherapy of NHL, and showed low brain and lung uptakes and low yttrium deposition into bone.

Conclusion

Findings of this study suggest that further investigations may result in a lyophilized (kit) formulation of DOTA-rituximab which could be easily radiolabeled with 90Y and 111In in order to be used for radioimmunotherapy and radioscintigraphy of B-cell lymphoma in Iran.  相似文献   
53.
Oleoylethanolamide (OEA) is an endogenous lipid that contributes in important ways to the peripheral regulation of food intake. When administered intraperitoneally, OEA is a potent satiety-inducing anorexiant in rats and mice [Nature 414 (2001) 209; Neuropsycopharmacology 28 (2003) 1311; Nature 425 (2003) 90]. In the present study, we show that oral administration of OEA in pH-sensitive enteric-coated capsules produces a profound and long-lasting inhibition of food intake in free-feeding rats. This effect is accompanied by a marked elevation in OEA levels in the small intestine, but not in brain or muscle.  相似文献   
54.
The critical role of metal ions and in particular iron in oxidative stress and protein aggregation offers chelation therapy as a sensible pharmaceutical strategy in oxidative stress‐induced neuronal damages. In this research, we conjugated an iron‐chelating agent, deferasirox, to cationized human serum albumin molecules in order to develop a novel brain delivery system for the management of neurodegenerative disorders due to the significant role of oxidative stress‐induced neuronal injury in such diseases. Cationized albumin is known to be able to transport to brain tissue via adsorptive‐mediated transcytosis. The developed structures were molecularly characterized, and their conjugation ratio was determined. PC12 cell line was utilized to evaluate the neuroprotective features of these newly developed molecules in the presence of hydrogen peroxide neuronal damage and to identify the mechanisms behind the observed neuronal protection including apoptotic and autophagic pathways. Furthermore, a rat model of Alzheimer's disease was utilized to evaluate the impact of conjugated structures in vivo. Data analysis revealed that the conjugated species were able to hinder apoptotic cell death while enhancing autophagic process. The developed conjugated species were also able to attenuate amyloid beta‐induced learning deficits when administered peripherally.  相似文献   
55.
Growing evidence sheds light on the use of flavonoids as the promising alternatives for the treatment of chronic conditions, including cancer and neurodegenerative disorders. Accordingly, in the present study, we aimed at evaluating the effects of oral intake of two structurally different flavonoids 5-hydroxy-6,7,4?-trimethoxyflavone (flavone 1) and 5,7,4?-trihydroxyflavone (flavone 2) on recognition memory, hippocampal protein level of immediate early gene cFos and mitochondrial dynamic markers in Amyloid β (Aβ)-injected rats. Recognition aspect of memory and level of proteins were measured using novel object recognition test and Western blot, respectively. Our data indicated that even though flavone 1 was more effective than flavone 2 to prevent memory impairment, feeding with both flavones alleviated memory in Aβ-injected rats. Furthermore, in flavones-administered rats, mitochondrial dynamic balancing returned to the control level by the decline in Dynamin-related protein-1 protein level, a known marker for mitochondrial fission, and elevation in protein level of mitochondrial fusion factors Mitofusins 1 and 2. In parallel with behavior results, flavone 1 was more effectual on mitochondrial dynamic moderating. The more neuroprotective effects of flavone 1 could be attributed to its methylated structure leading to crossing of the blood-brain barrier with ease and metabolic stability and bioactivity.  相似文献   
56.
BACKGROUND: To report a case of a secondary plasmacytoma of the choroid. METHODS: Interventional case report with cytopathologic correlation. RESULTS: A 61-year-old male with a breast nodule and a 2-year history of multiple myeloma developed blurred vision and was found to have three confluent, ill-defined areas of choroidal thickening in the left eye. Cytopathology and immunohistochemistry of a transocular fine-needle aspiration biopsy of the largest lesion revealed atypical plasma cells diagnostic of plasmacytoma. Following external beam radiotherapy the choroidal tumors resolved completely. CONCLUSION: Secondary plasmacytoma, despite its rarity, should be included in the differential diagnosis of amelanotic choroidal tumors, particularly in patients with multiple myeloma. Radiotherapy is an effective treatment.  相似文献   
57.
Myofascial pain syndrome (MPS) is a common musculoskeletal disorder. This study was designed to compare the effects of aerobic exercise plus acupuncture with acupuncture alone in treatment of patients with MPS. Sixty-four patients (55 female and 9 male) with MPS in their neck and shoulders participated in the study with mean age of 33.1 ± 6.4 years. Participants were randomly allocated to aerobic exercise plus acupuncture (n = 32) or acupuncture alone (n = 32) groups. Outcome measurements included visual analog scale, pressure pain threshold, neck disability index, and quality of life that was measured with QoL-SF36 scale. Each group received 10 sessions of acupuncture in combination with aerobic exercise or acupuncture alone. The outcome measures were evaluated at baseline, at the end of the last treatment session, and at 1-month follow-up visit. While participants were waiting for their 1-month follow-up visit, the patients who received combination therapy were asked to continue their aerobic exercise by jogging 40 minutes a day. Although mean visual analog scale, pressure pain threshold, neck disability index, and QoL-SF36 were significantly improved in both groups (p < 0.001), there was no statistically significant difference among the measures between the two groups throughout the evaluated sessions. The interaction effect of time and groups did not show any significant difference among the outcome measures (p > 0.29).  相似文献   
58.
Protein- energy malnutrition, wasting and inflammation are frequent complication among patients with end-stage renal disease (ESRD). Malnutrition is associated with cardiac co-morbidity, inflammation and poor survival in ESRD patients. Serum albumin is a well-known marker of nutrition in ESRD patients. Serum albumin is still the most commonly used nutritional marker in ESRD patients. C-reactive protein (CRP), the major acute phase response (APR) protein is elevated in these patients. High CRP levels are linked to the degree of atherosclerosis in coronary, peripheral, and extracranial brain arteries. The aim of the present study was to investigate nutritional factor (albumin) and CRP levels in ESRD patients. In this cross- sectional study a total of 300 patients who had ESRD and had been on hemodialysis treatment for at least 6 months were selected. The laboratory tests consisted of measurement of CRP and albumin using high sensitive ELISA kits. The study patients included 157 males (52.3%) and 143 females (47.7%) with average age of 41.5 ± 14.3 years. Mean CRP level was 7.96 mg/ dl (±1.52), mean serum albumin was 4.07 g/dl (±0.19).Of 300 patients, 21 died (7%). These were patients with serum albumin <4 g/dl and CRP>9.5 mg/dl. This study showed that low albumin and high CRP levels are the main predictors for death. There was a significant difference between CRP and albumin levels in ESRD patients (P<0.0001). Measuring CRP as a marker of inflammation can be helpful in managing these patients.  相似文献   
59.

Background

Leishmaniasis has been identified as a major public health problem in tropical and sub-tropical countries. The present study was aimed to investigate antileishmanial effects of various extracts of Berberis vulgaris also its active compoenent, berberine against Leishmania tropica and L. infantum species on in vitro experiments.

Methods

In this study in vitro antileishmanial activity of various extracts of B. vulgaris also its active compoenent, berberine against promastigote and amastigote stages of L. tropica and L. infantum was evaluated, using MTT assay and in a macrophage model, respectively. Furthermore, infectivity rate and cytotoxicity effects of B. vulgaris and berberine in murine macrophage cells were investigated.

Results

The findings of optical density (OD) and IC50 indicated that B. vulgaris particulary berberine significantly (P<0.05) inhibited the growth rate of promastigote stage of L.tropica and L.infantum in comparison to meglumine antimoniate (MA). In addition, B. vulgaris and berberine significantly (P<0.05) decreased the mean number of amastigotes in each macrophage as compared with positive control. In the evaluation of cytotoxicity effects, it could be observed that berberine as compared with B. vulgaris exhibited more cytotoxicity against murine macrophages. Results also showed that when parasites were pre-incubated with B. vulgaris their ability to infect murine macrophages was significantly decreased.

Conclusion

B.vulgaris particularly berberine exhibited potent in vitro leishmanicidal effects against L. tropica and L.infantum. Further works are required to evaluate the antileishmanial effects of B.vulgaris on Leishmania species using clinical settings.  相似文献   
60.
Objective: The aim of the present study was to determine the accuracy of commonly used predictive formulas of resting metabolic rate (RMR) compared to measured RMR in normal and overweight young females.

Methods: In this cross-sectional study, 98 female university students aged 18–30 years with body mass index 18 to 30 kg/m2 were recruited. Anthropometric indices and body compositions were measured. RMR was measured by indirect calorimetry (FitMate, Cosmed, Rome, Italy) and estimated by 11 predictive formulas. The accuracy of the RMR formulas and mean percentage differences between estimated and measured values were calculated. Paired t test was used to compare estimated and measured RMRs.

Result: There were no significant differences between measured and estimated RMR by the 4 commonly used formulas (Mifflin, Cunningham, and World Health Organization [WHO]/Food and Agriculture Organization [FAO]). Among all of the equations, the Mifflin formula showed the lowest bias (?2.97 ± 116.43 kcal/day) at the group level and was the most accurate formula (80.23%) in normal and overweight participants. The over- and underestimated values were about 14% and 5.5%, respectively. In normal and overweight females, Mifflin was the most accurate formula, with 75.51% and 84.61% accuracy, respectively.

Conclusion: Given the current lack of a standardized formula that consistently delivers accurate results, the Mifflin formula can be recommended for estimating energy requirements in normal and overweight females in clinical practice.  相似文献   
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