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Nirvani S. Henrique ◽  
Katia L. Maltoni ◽  
Glaucia A. Faria

ABSTRACT Litterfall is an important source of soil nutrients, but its decomposition can be affected by the crop system used. The objective of this study was to evaluate litterfall decomposition and macronutrient stocks in coffee crop systems in shaded (SHCS) environments and those in full sun (FSCS). The experiment was conducted on a rural property in Cacoal, state of Rondônia, Brazil, in a 2 × 6 factorial scheme with two crop systems (SHCS and FSCS), and six litterfall decomposition evaluation times (0, 30, 60, 180, 300, and 360 days after the litterfall was returned to the soil (DAL)), with seven replicates. The constant of decomposition (k), half-life time (t1/2) at 360 DAL, and phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), and nitrogen (N) concentrations of the remaining litterfall were determined at each evaluation time. The litterfall in the SHCS had a greater weight loss and constant of decomposition and a lower half-life time at the last evaluation, and the weight loss increased as a function of decomposition time. The litterfall stocks of macronutrients N, P, K, Ca, and Mg showed a linear decrease throughout the decomposition time, and increases in sulfur stock were found at the last evaluation.

2022 ◽  
Vol 12 (1) ◽  
Fatemeh Yadavar Nikravesh ◽  
Samira Shirkhani ◽  
Elham Bayat ◽  
Yeganeh Talebkhan ◽  
Esmat Mirabzadeh ◽  

AbstractGranulocyte colony stimulating factor (GCSF) can decrease mortality of patients undergo chemotherapy through increasing neutrophil counts. Many strategies have been developed to improve its blood circulating time. Albumin binding domain (ABD) was genetically fused to N-terminal end of GCSF encoding sequence and expressed as cytoplasmic inclusion bodies within Escherichia coli. Biological activity of ABD-GCSF protein was assessed by proliferation assay on NFS-60 cells. Physicochemical properties were analyzed through size exclusion chromatography, circular dichroism, intrinsic fluorescence spectroscopy and dynamic light scattering. Pharmacodynamics and pharmacokinetic properties were also investigated in a neutropenic rat model. CD and IFS spectra revealed that ABD fusion to GCSF did not significantly affect the secondary and tertiary structures of the molecule. DLS and SEC results indicated the absence of aggregation formation. EC50 value of the ABD-GCSF in proliferation of NFS-60 cells was 75.76 pg/ml after 72 h in comparison with control GCSF molecules (Filgrastim: 73.1 pg/ml and PEG-Filgrastim: 44.6 pg/ml). Animal studies of ABD-GCSF represented improved serum half-life (9.3 ± 0.7 h) and consequently reduced renal clearance (16.1 ± 1.4 ml/h.kg) in comparison with Filgrastim (1.7 ± 0.1 h). Enhanced neutrophils count following administration of ABD-GCSF was comparable with Filgrastim and weaker than PEG-Filgrastim treated rats. In vitro and in vivo results suggested the ABD fusion as a potential approach for improving GCSF properties.

2022 ◽  
Christina C. Roggatz ◽  
Daniel R Parsons

Marine biofilms are functional communities that shape habitats by providing a range of structural and functional services integral to coastal ecosystems. Impacts of climate change on biological aspects of such communities are increasingly studied, but impacts on the chemicals that mediate key interactions of biofilm organisms have largely been overlooked. Acyl-homoserine lactones (AHLs), crucial bacterial signals within biofilms, are known to degrade through pH and temperature-dependent hydrolysis. However, the impact of climate change on AHLs and thus on biofilm form and function is presently unknown. This study investigates the impact of changes in pH and temperature on the hydrolysis rate, half-life time and quantitative abundance of different AHLs on daily and seasonal timescales for current conditions and future climate change scenarios. We established the mathematical relationships between pH, hydrolysis rates/half-life times and temperature, which revealed that natural daily pH-driven changes within biofilms cause the greatest fluctuations in AHL concentration (up to 9-fold). Season-dependant temperature enhanced or reduced the observed daily dynamics, leading to higher winter and lower summer concentrations and caused a shift in timing of the highest and lowest AHL concentration by up to two hours. Simulated future conditions based on climate change projections caused an overall reduction of AHL degradation and led to higher AHL concentrations persisting for longer across both the daily and seasonal cycles. This study provides valuable quantitative insights into the theoretical natural dynamics of AHL concentrations. We highlight critical knowledge gaps on the scale of abiotic daily and seasonal fluctuations affecting estuarine and coastal biofilms and on the biofilms' buffering capacity. Detailed experimental studies of daily and seasonal dynamics of AHL concentrations and assessment of the potential implications for a suite of more complex interactions are required. Substantial fluctuations like those we show in this study, particularly with regards to concentration and timing, will likely have far reaching implications for fundamental ecosystem processes and important ecosystem services such as larval settlement and coastal sediment stabilisation.

Sarah M. Ozawa ◽  
David Sanchez-Migallon Guzman ◽  
Michelle G. Hawkins ◽  
Stephanie M. Diao ◽  
Acacia E. Masri ◽  

Abstract OBJECTIVE To determine the pharmacokinetics and potential adverse effects of pimobendan after oral administration in New Zealand White rabbits (Ocytolagus cuniculi). ANIMALS 10 adult sexually intact (5 males and 5 females) rabbits. PROCEDURES 2 pilot studies were performed with a pimobendan suspension or oral tablets. Eight rabbits received 7.5 mg of pimobendan (mean 2.08 mg/kg) suspended in a critical care feeding formula. Plasma concentrations of pimobendan and O-demethylpimobendan (ODMP) were measured, and pharmacokinetic parameters were calculated for pimobendan by noncompartmental analysis. Body weight, food and water consumption, mentation, urine, and fecal output were monitored. RESULTS Mean ± SD maximum concentration following pimobendan administration was 15.7 ± 7.54 ng/mL and was detected at 2.79 ± 1.25 hours. The half-life was 3.54 ± 1.32 hours. Plasma concentrations of pimobendan were detectable for up to 24 hours. The active metabolite, ODMP, was detected in rabbits for 24 to 36 hours. An adverse event occurred following administration of pimobendan in tablet form in 1 pilot study, resulting in death secondary to aspiration. No other adverse events occurred. CLINICAL RELEVANCE Plasma concentrations of pimobendan were lower than previously reported for dogs and cats, despite administration of higher doses, and had longer time to maximum concentration and half-life. Based on this study, 2 mg/kg of pimobendan in a critical care feeding formulation should maintain above a target plasma concentration for 12 to 24 hours. However, further studies evaluating multiple-dose administration as well as pharmacodynamic studies and clinical trials in rabbits with congestive heart failure are needed to determine accurate dose and frequency recommendations.

2022 ◽  
Vol 2022 ◽  
pp. 1-7
Yandri Yandri ◽  
Ezra Rheinsky Tiarsa ◽  
Tati Suhartati ◽  
Heri Satria ◽  
Bambang Irawan ◽  

The stability of the α-amylase enzyme has been improved from Aspergillus fumigatus using the immobilization method on a bentonite matrix. Therefore, this study aims to obtain the higher stability of α-amylase enzyme from A. fumigatus; hence, it is used repeatedly to reduce industrial costs. The procedures involved enzyme production, isolation, partial purification, immobilization, and characterization. Furthermore, the soluble enzyme was immobilized using 0.1 M phosphate buffer of pH 7.5 on a bentonite matrix, after which it was characterized with the following parameters such as optimum temperature, Michaelis constant (KM), maximum velocity V max , thermal inactivation rate constant (ki), half-life (t1/2), and the change of energy due to denaturation (ΔGi). The results showed that the soluble enzyme has an optimum temperature of 55°C, KM of 3.04 mg mL−1 substrate, V max of 10.90 μmole mL−1 min−1, ki of 0.0171 min−1, t1/2 of 40.53 min, and ΔGi of 104.47 kJ mole−1, while the immobilized enzyme has an optimum temperature of 70°C, KM of 8.31 mg mL−1 substrate, V max of 1.44 μmole mL−1 min−1, ki of 0.0060 min−1, t1/2 of 115.50 min, and ΔGi of 107.37 kJ mole−1. Considering the results, the immobilized enzyme retained 42% of its residual activity after six reuse cycles. Additionally, the stability improvement of the α-amylase enzyme by immobilization on a bentonite matrix, based on the increase in half-life, was three times greater than the soluble enzyme.

Xin Yuan ◽  
Yingzhou Qin ◽  
Qingmei Tian ◽  
Cuijuan Liu ◽  
Xiangzhou Meng ◽  

Abstract In the past decade, multifunctional peptides have attracted increasing attention in the biomedical field. Peptides possess many impressive advantages, such as high penetration ability, low cost, and etc. However, the short half-life and instability of peptides limit their application. In this study, a poly-peptide drug loading system (called HKMA composite) was designed based on the different functionalities of four peptides. The peptide compositions of HKMA composite from N-terminal to C-terminal were HCBP1, KLA, MMP-2-cleavable peptide and ABD. The targeting and lethality of HKMA to NSCLC cell line H460 sphere cells and the half-life of the system were measured in vivo. The results showed that the HKMA composite had a long half-life and specific killing effect on H460 sphere cells in vitro and in vivo. Our result proposed smart peptide drug loading system and provided a potential methodology for effective cancer treatment.


The current treatment approaches for allergic rhinitis are practiced over decades, but the patient quality of life has not yet changed so much. The reasons are research gaps in pathophysiology of the disease, proper management of the disease. Fexofenadine HCl is a second-generation antihistamine drug which has a half-life of about 14.4 h. It is useful in the management of common symptoms like sneezing, itchy throat, and red eyes in individuals suffering from allergic rhinitis. Fexofenadine immediate release or sustained release formulations are available in the market as suspension, tablet and capsule. In this research paper, we have discussed the symptoms associated with allergic rhinitis and treatment approaches. Fexofenadine HCl is being used for the treatment of this disease. But as it has a long half-life, we have discussed the importance of the introduction of sustained-release microsphere formulation of Fexofenadine HCl in the market.

Richard Wayne Leggett ◽  
Caleigh Samuels

Abstract The ICRP recently updated its biokinetic models for workers in a series of reports called the OIR (Occupational Intakes of Radionuclides) series. A new biokinetic model for astatine, the heaviest member of the halogen family, was adopted in OIR Part 5 (ICRP Publication 151, in press). This paper provides an overview of available biokinetic data for astatine; describes the basis for the ICRP’s updated model for astatine; and tabulates dose coefficients for intravenous injection of each of the two longest lived and most important astatine isotopes, 211At and 210At. Astatine-211 (T1/2 = 7.214 h) is a promising radionuclide for use in targeted α-particle therapy due to several favorable properties including its half-life and the absence of progeny that could deliver significant radiation doses outside the region of α-particle therapy. Astatine-210 (T1/2 = 8.1 h) is an impurity generated in the production of 211At in a cyclotron and represents a potential radiation hazard via its long-lived progeny 210Po (T1/2 = 138 d). Tissue dose coefficients for injected 210At and 211At based on the updated model are shown to differ considerably from values based on the ICRP’s previous model for astatine, particularly for the thyroid, stomach wall, salivary glands, lungs, spleen, and kidneys.

2022 ◽  
Erin Kuang ◽  
Robert W. Cross ◽  
Maria McCavitt-Malvido ◽  
Dafna M Abelson ◽  
Viktoriya Borisevich ◽  

Intravenous administration (IV) of antiviral monoclonal antibodies (mAbs) is challenging due to limited resources for performing infusions during an ongoing epidemic. An ebolavirus therapeutic administered via intramuscular (IM) injection would reduce these burdens and allow rapid treatment of exposed individuals during an outbreak. Here, we demonstrate how MBP134, a two mAb pan-ebolavirus cocktail, reverses the course of Sudan ebolavirus (SUDV/Gulu) disease with a single IV or IM dose in non-human primates (NHPs) as far as five days post-exposure. Furthermore, we investigated the utility of adding half-life extension mutations to the MBP134 mAbs, ultimately creating a half-life extended cocktail designated MBP431. MBP431 demonstrated an extended serum half-life in vivo and offered complete or significant protection with a single IM dose delivered as a post-exposure prophylactic (PEP) or therapeutic in NHPs challenged with EBOV. These results support the use of MBP431 as a rapidly deployable IM medical countermeasure against every known ebolavirus.

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