Preparation and radiolabeling of a lyophilized (kit) formulation of DOTA-rituximab with 90Y and 111In for domestic radioimmunotherapy and radioscintigraphy of Non-Hodgkin’s Lymphoma

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.     

In Vitro Inhibitory Effect of Berberis vulgaris (Berberidaceae) and Its Main Component,Berberine against Different Leishmania Species

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.     

Cationic Albumin‐Conjugated Chelating Agent as a Novel Brain Drug Delivery System in Neurodegeneration

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.     

Standardization of Prothrombin Time/International Normalized Ratio (PT/INR)

The prothrombin time (PT) represents the most commonly used coagulation test in clinical laboratories. The PT is mathematically converted to the international normalized ratio (INR) for use in monitoring anticoagulant therapy with vitamin K antagonists such as warfarin in order to provide test results that are adjusted for thromboplastin and instrument used. The INR is created using two major PT ‘correction factors’, namely the mean normal PT (MNPT) and the international sensitivity index (ISI). Manufacturers of reagents and coagulometers have made some efforts to harmonizing INRs, for example, by tailoring reagents to specific coagulometers and provide associated ISI values. Thus, two types of ISIs may be generated, with one being a ‘general’ or ‘generic’ ISI and others being reagent/coagulometer-specific ISI values. Although these play a crucial role in improving INR results between laboratories, these laboratories reported INR values are known to still differ, even when laboratories use the same thromboplastin reagent and coagulometer. Moreover, ISI values for a specific thromboplastin can vary among different models of coagulometers from a manufacturer using the same method for clot identification. All these factors can be sources of error for INR reporting, which in turn can significantly affect patient management. In this narrative review, we provide some guidance to appropriate ISI verification/validation, which may help decrease the variability in cross laboratory reporting of INRs.     

Coffee,caffeine, and risk of completed suicide: Results from three prospective cohorts of American adults

Objective.To evaluate the association between coffee and caffeine consumption and suicide risk in three large-scale cohorts of US men and women. Methods. We accessed data of 43,599 men enrolled in the Health Professionals Follow-up Study (HPFS, 1988–2008), 73,820 women in the Nurses’ Health Study (NHS, 1992–2008), and 91,005 women in the NHS II (1993–2007). Consumption of caffeine, coffee, and decaffeinated coffee, was assessed every 4 years by validated food-frequency questionnaires. Deaths from suicide were determined by physician review of death certificates. Multivariate adjusted relative risks (RRs) were estimated with Cox proportional hazard models. Cohort specific RRs were pooled using random-effect models. Results. We documented 277 deaths from suicide. Compared to those consuming ≤ 1 cup/week of caffeinated coffee (< 8 oz/237 ml), the pooled multivariate RR (95% confidence interval [CI]) of suicide was 0.55 (0.38–0.78) for those consuming 2–3 cups/day and 0.47 (0.27–0.81) for those consuming ≥ 4 cups/day (P trend < 0.001). The pooled multivariate RR (95% CI) for suicide was 0.75 (0.63–0.90) for each increment of 2 cups/day of caffeinated coffee and 0.77 (0.63–0.93) for each increment of 300 mg/day of caffeine. Conclusions. These results from three large cohorts support an association between caffeine consumption and lower risk of suicide.     

Grafted human chorionic stem cells restore motor function and preclude cerebellar neurodegeneration in rat model of cerebellar ataxia

Metabolic Brain Disease - Cerebellar ataxia (CA) is a form of ataxia that adversely affects the cerebellum. Cell replacement therapy (CRT) has been considered as a potential treatment for...     

Prenatal Folate and Choline Levels and Brain and Cognitive Development in Children: A Critical Narrative Review

Women’s nutritional status during pregnancy can have long-term effects on children’s brains and cognitive development. Folate and choline are methyl-donor nutrients and are important for closure of the neural tube during fetal development. They have also been associated with brain and cognitive development in children. Animal studies have observed that prenatal folate and choline supplementation is associated with better cognitive outcomes in offspring and that these nutrients may have interactive effects on brain development. Although some human studies have reported associations between maternal folate and choline levels and child cognitive outcomes, results are not consistent, and no human studies have investigated the potential interactive effects of folate and choline. This lack of consistency could be due to differences in the methods used to assess folate and choline levels, the gestational trimester at which they were measured, and lack of consideration of potential confounding variables. This narrative review discusses and critically reviews current research examining the associations between maternal levels of folate and choline during pregnancy and brain and cognitive development in children. Directions for future research that will increase our understanding of the effects of these nutrients on children’s neurodevelopment are discussed.