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101.
A green type composite biosorbent composed of pine, oak, hornbeam, and fir sawdust biomasses modified with cetyltrimethylammonium bromide (CTAB) was first used for biosorption of an unsafe synthetic food dye, Food Green 3 from liquid medium in this study. Batch studies were carried by observing the effects of pH, dye concentration, biosorbent amount, and contact time. The equilibrium data were analyzed using Freundlich, Langmuir, and Dubinin–Radushkevich equations. Freundlich model gave a better conformity than other equations. The maximum dye removal potential of biosorbent was found to be 36.6 mg/g based on Langmuir isotherm. The pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion models were applied to clarify the process kinetics of biosorption. The mechanism studies suggested the biosorption process obeying Elovich kinetics and involving pore diffusion. The estimated values of biosorption free energy from Dubinin–Radushkevich isotherm (E value <8 kJ/mol) and thermodynamic studies (0 < ΔG° < ?20 kJ/mol) implied a spontaneous, feasible, and physical process. Hence, this investigation suggested that the CTAB modified mix sawdust biomass could be a promising biosorbent for biosorption of such problematic dyes from impacted media. 相似文献
102.
103.
Zihan Li Luca Leustean Fatih Inci Min Zheng Utkan Demirci Shuqi Wang 《Biotechnology advances》2019,37(8):107440
Infectious diseases such as HIV-1/AIDS, tuberculosis (TB), hepatitis B (HBV), and malaria still exert a tremendous health burden on the developing world, requiring rapid, simple and inexpensive diagnostics for on-site diagnosis and treatment monitoring. However, traditional diagnostic methods such as nucleic acid tests (NATs) and enzyme linked immunosorbent assays (ELISA) cannot be readily implemented in point-of-care (POC) settings. Recently, plasmonic-based biosensors have emerged, offering an attractive solution to manage infectious diseases in the developing world since they can achieve rapid, real-time and label-free detection of various pathogenic biomarkers. Via the principle of plasmonic-based optical detection, a variety of biosensing technologies such as surface plasmon resonance (SPR), localized surface plasmon resonance (LSPR), colorimetric plasmonic assays, and surface enhanced Raman spectroscopy (SERS) have emerged for early diagnosis of HIV-1, TB, HBV and malaria. Similarly, plasmonic-based colorimetric assays have also been developed with the capability of multiplexing and cellphone integration, which is well suited for POC testing in the developing world. Herein, we present a comprehensive review on recent advances in surface chemistry, substrate fabrication, and microfluidic integration for the development of plasmonic-based biosensors, aiming at rapid management of infectious diseases at the POC, and thus improving global health. 相似文献
104.
105.
An efficient and modular one-pot synthesis of polysubstituted aromatic amines by a mild reductive amination procedure is described and the biological potential of these nitrogen-centered compounds is demonstrated by growth inhibition of murine connective tissue cells and microscopy-based morphological studies. 相似文献
106.
A Murat Aytekin Bulent Alten Selim S Caglar Yusuf Ozbel Sinan Kaynas Fatih M Simsek Ozge Erisoz Kasap Asli Belen 《Journal of vector ecology》2007,32(2):226-234
The wing-shape morphology of local populations of the medically important phlebotomine sand flies, Phlebotomus sergenti, P. papatasi, P. tobbi, and P. similis, were examined in both sexes by using geometric morphometrics. There are three major mountain ranges that may serve as geographical barriers for species distribution in the study area and four main gaps were recognized among these barriers. We found no statistically important differences in wing morphology in all examined species in both sexes for all local populations. These results show that the barriers are not sufficient to stop gene flow among local populations of sand flies. The graphical depiction of PCA, CVA, and F-test confirmed our morphometric study suggesting that the difference in wing morphology between P. similis and P. sergenti indicates that these are clearly different species. These two show sympatric distribution in the Konya Plain of Anatolia. 相似文献
107.
Differential expression of proliferative, cytoskeletal, and adhesive proteins during postnatal development of the hamster submandibular gland 总被引:1,自引:1,他引:0
Fernandes RP Cotanche DA Lennon-Hopkins K Erkan F Menko AS Kukuruzinska MA 《Histochemistry and cell biology》1999,111(2):153-162
Although the submandibular gland (SMG) plays important exocrine and endocrine roles, little is known about the molecular
details underlying its development. Previously, we reported that in the postnatally developing hamster SMG, GPT, the protein
product of the first N-glycosylation gene, ALG7, was an in vivo marker for salivary cell proliferation. Here we investigated the proliferative,
cytoskeletal, and adhesive changes during SMG postnatal development. The cellular localization and abundance of GPT, filamentous
actin, and β1 integrin receptor were examined using confocal microscopy and immunoblotting. In neonatal glands, high GPT levels
marked extensive cell proliferation throughout the tissue. The apical regions of immature salivary cells displayed intense
actin staining, while most of the β1 integrin was diffusely distributed throughout the tissue. As development proceeded, discrete
regions of the gland expressed attenuated levels of GPT, an increased organization of actin to the cell cortex, and β1 integrin
to the basal lamina. In the adult SMG, differentiated salivary cells displayed low levels of GPT and actin. While the abundance
of β1 integrin remained unchanged throughout development, in the adult, it was found exclusively in regions where cells contact
the basal lamina. These data indicate that SMG development entails regionalized cell proliferation and polarization, and that
these processes are temporally and spatially coordinated with the establishment of stable cell-substratum interactions.
Accepted: 26 October 1998 相似文献
108.
The purpose of the study was to synthesize and evaluate the antimicrobial effects of two monophosphazenes, N-diphenylphosphoryl-P-triphenylmonophosphazene-II and N-di(o-tolyl)phosphoryl-P-tri(o-tolyl)monophosphazene-III on bacterial and yeast strains. The biological effects of these molecules were compared with a potential antioxidant vitamin E. According to results, the triphenyl monophosphazene-II has antimicrobial effect on all the bacterial and yeast cells, but tri(o-tolyl)monophosphazene-III has only antimicrobial effect on some bacterial cells. When the concentration of triphenyl monophosphazene-II was raised, it was observed that inhibition zone increased on the bacterial growth media. The biological effects of these molecules were compared to vitamin E in the Saccharomyces cerevisiae culture media. In 200 microg administered culture media, the cell density decreased in vitamin E, triphenyl monophosphazene-II and tri(o-tolyl)monophosphazene-III groups at the end of 24 and 48 h incubation times (p<0.001,p<0.05). While the cell densities in vitamin E and tri(o-tolyl)monophosphazene-II groups decreased partly at the end of 72 h incubation time (p<0.05), its level in triphenyl monophosphazene-II group increased (p<0.01) at the same incubation time. In 1,000 microg administered culture media, cell density was not found to differ between vitamin E and control groups at the end of 24h incubation time, but it was found that the cell densities in triphenyl monophosphazene and tri(o-tolyl)monophosphazene-III groups decreased at the same incubation time (p<0.001). The cell densities in tri(o-tolyl)monophosphazene-III group and triphenyl monophosphazene-II decreased at the end of 48 h incubation time (respectively, p<0.05,p<0.001). In 200 microg administered cell pellets, while the lipid level was not found to differ between control and vitamin E, the lipid level decreased in triphenyl monophosphazene-II and tri(o-tolyl)monophospazene-III groups (respectively, p<0.001,p<0.01). In 1,000 microg administered cell pellets, it was found that the lipid level decreased in vitamin E, triphenyl monophosphazene-II and tri(o-tolyl)monophosphazene-III groups (p<0.001,p<0.01). 相似文献
109.
Quanzhi Li Wendy Hudson Duo Wang Erica Berven Fatih M. Uckun John H. Kersey 《Cancer immunology, immunotherapy : CII》1998,47(3):121-130
The comparative advantages and disadvantages of intact antibodies and single-chain Fv as immunotoxins and radioimmunoconjugates
have been widely discussed but not directly compared. In this study, the in vivo properties of anti-CD19 B43 monoclonal antibody
and its derived single-chain Fv (FVS191) were studied in athymic nude mice bearing CD19-positive human lymphomas. B43 mab
and FVS191 were labeled with iodine-125 using iodine-beads, and immunoreactivities were determined to be 57% and 72%, respectively.
Scatchard analysis showed a similar high affinity for both. The results of pharmacokinetic studies revealed that FVS191 had
a rapid biphasic clearance from the circulation (T1/2α = 2.5 min, T1/2β = 3.7 h); The T1/2α and T1/2β phases of B43 mab were
determined to be 0.72 h and 57 h respectively. Biodistribution studies compared the uptake of labeled antibodies by CD19-positive
and by CD19-negative tumors. The peak percentages of injected dose were 5.7% at 12 h for B43 and 2.45% at 1 h for FVS191.
Radiolocalization indices (RI) demonstrated tumor-specific uptake for both, but higher uptake for B43. The optimal RI was
seen at 15 min for FVS191 and 6 h for B43. FVS191 was unstable in vivo, approximately 50% of the injected dose being degraded
in blood in 100 min. Radioactivity detected in the urine was present mainly as the deiodinized form of FVS191. The results
suggest that B43 mab is favored over FVS191 in biodistribution properties and in vivo stability. Because B43 Mab showed early
tumor-specific uptake, high RI values, and favorable tissue-to-blood ratios, it is a potential candidate for radioimmunotherapy
and immunotoxin therapy of B-cell leukemia and lymphoma.
Received: 17 June 1997 / Accepted: 17 June 1998 相似文献
110.
Fatih Karadagli Andrew Marcus Bruce E. Rittmann 《Biotechnology and bioengineering》2023,120(7):1844-1856
Hydrogen (H2) concentrations that were associated with microbiological respiratory processes (RPs) such as sulfate reduction and methanogenesis were quantified in continuous-flow systems (CFSs) (e.g., bioreactors, sediments). Gibbs free energy yield (ΔǴ ~ 0) of the relevant RP has been proposed to control the observed H2 concentrations, but most of the reported values do not align with the proposed energetic trends. Alternatively, we postulate that system characteristics of each experimental design influence all system components including H2 concentrations. To analyze this proposal, a Monod-based mathematical model was developed and used to design a gas–liquid bioreactor for hydrogenotrophic methanogenesis with Methanobacterium bryantii M.o.H. Gas-to-liquid H2 mass transfer, microbiological H2 consumption, biomass growth, methane formation, and Gibbs free energy yields were evaluated systematically. Combining model predictions and experimental results revealed that an initially large biomass concentration created transients during which biomass consumed [H2]L rapidly to the thermodynamic H2-threshold (≤1 nM) that triggerred the microorganisms to stop H2 oxidation. With no H2 oxidation, continuous gas-to-liquid H2 transfer increased [H2]L to a level that signaled the methanogens to resume H2 oxidation. Thus, an oscillatory H2-concentration profile developed between the thermodynamic H2-threshold (≤1 nM) and a low [H2]L (~10 nM) that relied on the rate of gas-to-liquid H2-transfer. The transient [H2]L values were too low to support biomass synthesis that could balance biomass losses through endogenous oxidation and advection; thus, biomass declined continuously and disappeared. A stable [H2]L (1807 nM) emerged as a result of abiotic H2-balance between gas-to-liquid H2 transfer and H2 removal via advection of liquid-phase. 相似文献