Behavioral responses to intracerebroventricularly administered neurohypophyseal peptides in mice

Lysine vasopressin (LVP), arginine vasopressin, oxytocin, and arginine vasotocin administered intraventricularly (icv) to mice all provoked a dose-dependent behavioral response in the range 0.1 – 1.0 μg. This response included a pronounced hyperactivity, extensive foraging, increased grooming, and at higher doses, stereotyped scratching, squeaking, and occasional barrel rolling. The four hormones were all approximately equipotent. Desglycinamide lysine vasopressin and [desaminocys₁, D-Arg₈] vasopressin produced some of the characteristic behaviors, but were much less potent. While pretreatment of the animals with reserpine (5 mg/kg ip), haloperidol (0.5 mg/kg ip), or physostigmine (0.5 mg/kg ip) sedated the animals and attenuated the locomotion and grooming, these drugs did not substantially alter the characteristic behavioral responses to LVP. Pretreatment with α-methyl-p-tyrosine (400 mg/kg ip), p-chlorophenylalanine (320 mg/kg ip), 6-hydroxydopamine (100 μg icv), ergotamine (0.5 μg icv), ethoxolamide (52 ng icv), diphenhydramine (20 μg icv), prostaglondin F_2α (2 μg icv), or naloxone (1 mg/kg ip) did not alter the LVP-induced behaviors. None of these drugs or -amphetamine (0.5 to 20 mg/kg ip) or nicotine (0.1 or 1 μg icv) mimicked the behavioral effects of the hormones.     

Relationship of posture and age to urinary protein excretion.

The influence of posture and age on urinary protein excretion was studied in 120 normal men volunteers. The supine excretion rate was less than 140 mug/min in all but two people (median value 38 mug/min) and tended to increase with age. The excretion rate decreased on quiet standing in 80% of people, which corresponded to a fall in creatinine-clearance. In the remaining 20% protein excretion increased on standing but generally remained within normal limits and was dissociated from changes in creatinine clearances. This increase was more prevalent in younger people and may represent a phenomenon analogous to orthostatic proteinuria, differing only quantitatively.     

Optimising Immunogenicity with Viral Vectors: Mixing MVA and HAdV-5 Expressing the Mycobacterial Antigen Ag85A in a Single Injection

The Bacillus Calmette - Guerin (BCG) vaccine provides a critical but limited defense against Mycobacterium tuberculosis (M.tb). More than 60 years after the widespread introduction of BCG, there is an urgent need for a better vaccine. A large body of pre-clinical research continues to support ongoing clinical trials to assess whether viral vectors expressing M.tb antigens that are shared by BCG and M.tb, can be used alongside BCG to enhance protection. A major focus involves using multiple unique viral vectors to limit anti-vector immunity and thereby enhance responses to the insert antigen delivered. The successful introduction of viral vector vaccines to target M.tb and other pathogens will be reliant on reducing the costs when using multiple vectors and inhibiting the development of unwanted anti-vector responses that interfere with the response to insert antigen. This study examines methods to reduce the logistical costs of vaccination by mixing different viral vectors that share the same insert antigen in one vaccine; and whether combining different viral vectors reduces anti-vector immunity to improve immunogenicity to the insert antigen. Here we show that a homologous prime-boost regimen with a mixture of MVA (Modified Vaccinia virus Ankara) and Ad5 (human adenovirus type 5) vectors both expressing Ag85A in a single vaccine preparation is able to reduce anti-vector immunity, compared with a homologous prime-boost regimen with either vector alone. However, the level of immunogenicity induced by the homologous mixture remained comparable to that induced with single viral vectors and was less immunogenic than a heterologous Ad5 prime-MVA-boost regimen. These findings advance the understanding of how anti-vector immunity maybe reduced in viral vector vaccination regimens. Furthermore, an insight is provided to the impact on vaccine immunogenicity from altering vaccination methods to reduce the logistical demands of using separate vaccine preparations in the field.     

Elimination of African Onchocerciasis: Modeling the Impact of Increasing the Frequency of Ivermectin Mass Treatment

The African Programme for Onchocerciasis Control (APOC) is currently shifting its focus from morbidity control to elimination of infection. To enhance the likelihood of elimination and speed up its achievement, programs may consider to increase the frequency of ivermectin mass treatment from annual to 6-monthly or even higher. In a computer simulation study, we examined the potential impact of increasing the mass treatment frequency for different settings. With the ONCHOSIM model, we simulated 92,610 scenarios pertaining to different assumptions about transmission conditions, history of mass treatment, the future mass treatment strategy, and ivermectin efficacy. Simulation results were used to determine the minimum remaining program duration and number of treatment rounds required to achieve 99% probability of elimination. Doubling the frequency of treatment from yearly to 6-monthly or 3-monthly was predicted to reduce remaining program duration by about 40% or 60%, respectively. These reductions come at a cost of additional treatment rounds, especially in case of 3-monthly mass treatment. Also, aforementioned reductions are highly dependent on maintained coverage, and could be completely nullified if coverage of mass treatment were to fall in the future. In low coverage settings, increasing treatment coverage is almost just as effective as increasing treatment frequency. We conclude that 6-monthly mass treatment may only be worth the effort in situations where annual treatment is expected to take a long time to achieve elimination in spite of good treatment coverage, e.g. because of unfavorable transmission conditions or because mass treatment started recently.     

A Novel Piggybac Transposon Inducible Expression System Identifies a Role for Akt Signalling in Primordial Germ Cell Migration

In this work, we describe a single piggyBac transposon system containing both a tet-activator and a doxycycline-inducible expression cassette. We demonstrate that a gene product can be conditionally expressed from the integrated transposon and a second gene can be simultaneously targeted by a short hairpin RNA contained within the transposon, both in vivo and in mammalian and avian cell lines. We applied this system to stably modify chicken primordial germ cell (PGC) lines in vitro and induce a reporter gene at specific developmental stages after injection of the transposon-modified germ cells into chicken embryos. We used this vector to express a constitutively-active AKT molecule during PGC migration to the forming gonad. We found that PGC migration was retarded and cells could not colonise the forming gonad. Correct levels of AKT activation are thus essential for germ cell migration during early embryonic development.     

Phenothiazine–rhodamine‐based colorimetric and fluorogenic ‘turn‐on' sensor for Zn2+ and bioimaging studies in live cells

A phenothiazine–rhodamine (PTRH) fluorescent dyad was synthesized and its ability to selectively sense Zn²⁺ ions in solution and in in vitro cell lines was tested using various techniques. When compared with other competing metal ions, the PTRH probe showed the high selectivity for Zn²⁺ ions that was supported by electronic and emission spectral analyses. The emission band at 528 nm for the PTRH probe indicated the ring closed form of PTRH, as for Zn²⁺ ion binding to PTRH, the λ_em get shift to 608 nm was accompanied by a pale yellow to pink colour (under visible light) and green to pinkish red fluorescence emission (under UV light) due to ring opening of the spirolactam moiety in the PTRH ligand. Spectral overlap of the donor emission band and the absorption band of the ring opened form of the acceptor moiety contributed towards the fluorescence resonance energy transfer ON mechanism for Zn²⁺ ion detection. The PTRH sensor had the lowest detection limit for Zn²⁺, found to be 2.89 × 10^?8 M. The sensor also demonstrated good sensing application with minimum toxicity for in vitro analyses using HeLa cells.