Genetic,cytogenetic and morphological diversity in Helicrysum leucocephalum (Asteraceae) populations

Helichrysum (family Asteraceae) is a large, heterogeneous and polyphyletic genus. Most of the Helichrysum species have ornamental and medicinal values. Helicrysum leucocephalum Boiss., has wide geographical distribution in Iran and forms several local populations. The present investigation was performed to study inter populations, genetic, cytogenetic and morphological diversity of this medicinal species. The AMOVA test showed significant genetic difference among the studied populations but the Mantel test did not show correlation between the genetic distance and geographical distance of these populations. STRUCTURE and reticulation analyses showed some degree of genetic admixture and gene exchange among the studied populations. These populations had different chromosome numbers and also differed significantly in the size of their chromosomes.     

T cells expressing VHH-directed oligoclonal chimeric HER2 antigen receptors: Towards tumor-directed oligoclonal T cell therapy

Background

Adoptive cell therapy with engineered T cells expressing chimeric antigen receptors (CARs) originated from antibodies is a promising strategy in cancer immunotherapy. Several unsuccessful trials, however, highlight the need for alternative conventional binding domains and the better combination of costimulatory endodomains for CAR construction to improve the effector functions of the engineered T cells. Camelid single-domain antibodies (VHHs), which are the smallest single domain antibodies, can endow great targeting ability to CAR-engineered T cells.

Methods

We have developed a method to generate genetically engineered Jurkat T cells armed with a CAR comprising the anti-HER2 VHH as targeting moiety. From an immune camel library, five VHH clones were selected as a set of oligoclonal anti-HER2 VHHs that exhibited diverse binding abilities and joined them to CD28-CD3ζ and CD28-OX40-CD3ζ signaling endodomains. Jurkat T cells expression of VHH-CARs and cell functions were evaluated.

Results

The oligoclonal engineered T cells showed higher proliferation, cytokine secretion and cytotoxicity than each individual VHH-CAR-engineered Jurkat T cells.

Conclusions

The combination of superior targeting ability of oligoclonal VHHs with the third generation CAR can substantially improve the function of engineered T cells.

General significance

Antigen-specific directed oligoclonal T cells are alternatively promising, but safer systems, to combat tumor cells.     

Locomotor function shapes the passive mechanical properties and operating lengths of muscle

Locomotor muscles often perform diverse roles, functioning as motors that produce mechanical energy, struts that produce force and brakes that dissipate mechanical energy. In many vertebrate muscles, these functions are not mutually exclusive and a single muscle often performs a range of mechanically diverse tasks. This functional diversity has obscured the relationship between a muscle''s locomotor function and its mechanical properties. I use hopping in toads as a model system for comparing muscles that primarily produce mechanical energy with muscles that primarily dissipate mechanical energy. During hopping, hindlimb muscles undergo active shortening to produce mechanical energy and propel the animal into the air, whereas the forelimb muscles undergo active lengthening to dissipate mechanical energy during landing. Muscles performing distinct mechanical functions operate on different regions of the force–length curve. These findings suggest that a muscle''s operating length may be shaped by potential trade-offs between force production and sarcomere stability. In addition, the passive force–length properties of hindlimb and forelimb muscles vary, suggesting that passive stiffness functions to restrict the muscle''s operating length in vivo. These results inform our understanding of vertebrate muscle variation by providing a clear link between a muscle''s locomotor function and its mechanical properties.     

Evaluation of Alginate/Chitosan nanoparticles as antisense delivery vector: Formulation,optimization and in vitro characterization

Nanoparticles comprising Alginate/Chitosan polymers were prepared by pregel preparation method through drop wise addition of various concentrations of CaCl₂ to a defined concentration of Sodium Alginate. Then, Chitosan/Antisense solution with a certain N/P ratio was added to the pregel to make the nanoparticles. The effect of such parameters as polymer ratio, CaCl₂/Alginate ratio and N/P ratio on the particle size distribution and loading efficacy was studied. The optimum conditions were 1:1 (w/w) Alginate to Chitosan ratio, 0.2% CaCl₂/Alginate ratio and N/P ratio of 5 at pH 5.3. The resulting nanoparticles had a loading efficacy of 95.6% and average size of 194 nm as confirmed by PCS method and SEM images showed spherical and smooth particles. The zeta potential of optimized nanoparticles prepared by this method was about +30 mV which could result in good stability of nanoparticles during manipulation and storage.     

Factors that influence decisions by families to donate brain tissue for medical research

Whilst mainstream transplant literature provides valuable insights into the influences on families to donate organs and tissues for transplant, the relevance of these findings in relation to organ donation for research remain speculative. The present study aims to expand the research donation literature, by exploring factors that influence a family’s decision to donate brain tissue to neuroscience research. The verbal responses of the senior available next-of-kin (NOK), to the question of brain donation for research, are analysed. The donation rate was high (54%) over the 5-year-period. NOK relationship to the deceased, and post mortem interval were the main factors associated with a positive donation. Parents were most likely to donate and this may result from a lifetime of decision-making on behalf of the deceased. Also, the longer the interval between death of the potential donor and the question being asked, the greater the likelihood of donation.     

Reference values for serum nitric oxide metabolites in pediatrics

Serum concentration of nitric oxide metabolites (NO_x) is associated with cardiovascular disease risk factors in pediatrics. The aim of this study was to determine sex- and age-specific reference ranges for serum NO_x concentrations in pediatrics. Serum NO_x levels were measured in 401 subjects (189 boys and 212 girls), aged 4–19 years, using the Griess method. Study subjects selected from participants of Tehran lipid and glucose study, an ongoing cohort study aimed at determining of noncommunicable disease risk factors among Tehranian subjects. The International Federation of Clinical Chemistry guidelines and the robust method were used for determining reference values for sample sizes greater or less than 120 respectively. The 95% reference values for serum NO_x concentrations were 13.6–69.2, 11.4–66.0, and 12.2–69.4 μmol/L in boys, girls, and total population respectively. The upper limit of serum NO_x was 28% lower in otherwise healthy overweight and obese boys while it was 6% higher in overweight and obese girls, for both groups compared to their corresponding normal weight subjects. In conclusion, this study, for the first time, reports reference values for serum NO_x levels in healthy children and adolescents.     

The role of liposome charge on immune response generated in BALB/c mice immunized with recombinant major surface glycoprotein of Leishmania (rgp63)

Liposomes as a lipid-based system have been shown to be an effective adjuvant formulation. In this study, the role of liposome charge in induction of a Th1 type of immune response and protection against leishmaniasis in BALB/c mice was studied. Liposomes containing rgp63 were prepared by Dehydration-Rehydration Vesicle (DRV) method. Neutral liposomes consisted of dipalmitoylphosphatidylcholine and cholesterol. Positively and negatively charged liposomes were prepared by adding dimethyldioctadecylammonium bromide (DDAB) or dicetyl phosphate (DCP) to the neutral liposome formulation, respectively. Female BALB/c mice were immunized subcutaneously with negatively, positively charged or neutral liposomes encapsulated with rgp63, rgp63 in soluble form or PBS, three times in 3 week intervals. The extent of protection and type of immune response generated were studied in different groups of mice. The group of mice immunized with rgp63 encapsulated in neutral liposomes showed a significantly (P < 0.01) smaller footpad swelling upon challenge with Leishmania major compared with positively or negatively charged liposomes. The mice immunized with neutral liposomes also showed a significantly (P < 0.01) the lowest splenic parasite burden, the highest IgG2a/IgG1 ratio and IFN-γ production and the lowest IL-4 level compared to the other groups. The results indicated that a Th1 type of immune response was induced in mice immunized with neutral liposomes more efficiently than positively charged liposomes and conversely negatively charged liposomes induced a Th2 type of immune response.     

Seasonal variation of neonatal transient hyperthyrotropinemia in Tehran province, 1998-2005

Seasonal aggregation and the monthly rate of neonatal transient hyperthyrotropinemia (THT) were assessed. From November 1998 to April 2005, neonates of gestational age ≥37 wks, birth weight 2500-4000?g, birth length 45-55 cm, and 1st min Apgar score >3, who had thyrotropin (TSH) ≥20 mU/L in their cord dried-blood specimen, but without congenital hypothyroidism, were enrolled in the study. The recall rate equals the rate of THT occurrence in this study. Of 47,945 neonates, 555 had THT (recall rate: 1.2%). The aggregated seasonal recall rate (recall for further assessment to rule out congenital hypothyroidism) was significantly higher in winter (January, February, and March) than the other seasons (p < .0001). Winter had higher recall rate in each year as compared to other seasons, but the overall rate of recalls decreased in 2001 and 2002. Excluding the first 6 months (due to erratic variations), the remaining 72 months revealed a relatively sinusoidal pattern in monthly recall rates; indeed, there was an initial 11-month high recall rates (1.7%), followed by a 33-month decrease (0.7%), a 19-month increase (1.9%), and a final 9-month decrease (0.8%). The recall rate of each of these time intervals was significantly different from that of the next time interval (p < .0001). The monthly recall rates were best fitted to cubic curve estimation and then autoregressive integrated moving average (ARIMA) (0, 1, 1) models. THT occurs significantly more in winter than in other seasons, and this suggests a possible role for time-varying factor(s) contributing to its seasonal preponderance.     

Optimization of Enzymatic Hydrolysis Conditions of Caspian kutum (Rutilus frisii kutum)ˮ By-product for Production of Bioactive Peptides with Antioxidative Properties

The enzymatic hydrolysis was performed by Alcalase to recover the fish protein hydrolysate from Caspian kutum by-product (CB). The degree of hydrolysis (DH) was applied for monitoring the hydrolysis reaction of CB. The response surface methodology was applied based on a D-optimal design to perform the optimization process for obtaining the high yield of CB protein hydrolysate. The effect of four independent variables including pH (7.5–8.5), temperature (45–55 °C), time (1–3 h), and enzyme concentration (0.5–1.5% w/w) on DH was studied. The results indicated that the predicted and actual values of the optimum condition had no significant difference. The optimum enzymatic hydrolysis conditions were achieved at pH 8.5, temperature of 55 °C, enzyme concentration of 1.5% w/w, and time of 3 h, which resulted in the maximum value of DH (19.08%). Antioxidant assays including DPPH scavenging and metal chelating activities showed that Caspian kutum protein hydrolysates had antioxidant properties.

     

Prenatal Testosterone Exposure Worsen the Reproductive Performance of Male Rat at Adulthood

The reproductive system is extremely susceptible to environmental insults, for example exogenous steroids during gestational development and differentiation. Experimental induction of androgen excess during prenatal life in female animal models reprograms their reproductive physiology, however the fetal programming of the male reproductive system by androgen excess has not been well studied. We aimed to determine the effect of prenatal exposure of two different doses of testosterone on different gestational days, on the male reproductive system using a rat model. Sixteen pregnant rats were randomly divided into two experimental groups and two control groups. Experimental group І were subcutaneously injected with 3 mg free testosterone on gestational days 16-19 and its controls received solvent for that time; experimental group П were subcutaneously injected with 20 mg free testosterone on day 20 of gestational period and its controls received solvent at the same time. The reproductive system morphology and function of 32 male offspring of these study groups were compared at days 6-30-60 of age and after puberty. The anogenital distance of the male offspring of both experimental groups had no significant differences on the different days of measurement, compared with controls. In the offspring of experimental group І, the testes weight, number of Sertoli, Spermatocyte and Spermatid cells, sperm count and motility and the serum concentration of testosterone after puberty were significantly decreased; except for reduction of sperm motility (p< 0.01), the other effects were not observed in the offspring of experimental group ІІ. In summary, our data show that prenatal exposure of male rat fetuses to excess testosterone disrupted reproductive function, an effect highly dependent on the time, duration and level of exposure. It seems that the reproductive system in individuals exposed to high levels of androgens during fetal life should be evaluated at puberty and likely to be treated.