Magnetically Guided Nanoworms for Precise Delivery to Enhance In Situ Production of Nitric Oxide to Combat Focal Bacterial Infection In Vivo

Author(s):  
Bitao Lu ◽  
Enling Hu ◽  
Ruiqi Xie ◽  
Kun Yu ◽  
Fei Lu ◽  
...  
1992 ◽  
Vol 175 (6) ◽  
pp. 1793-1797 ◽  
Author(s):  
H U Beuscher ◽  
U P Rausch ◽  
I G Otterness ◽  
M Röllinghoff

In situ production of interleukin 1 alpha (IL-1 alpha) and IL-1 beta was investigated in Peyer's patches (PP) of mice undergoing an acute bacterial infection with Yersinia enterocolitica O8. Synthesis of IL-1 beta, as determined by immunohistochemistry, was found primarily in monocytes migrating into the inflamed PP. In comparison, synthesis of IL-1 alpha was temporarily delayed by at least 24 h and was only found in mature macrophages, which did not produce detectable levels of IL-1 beta. This indicates a transition from IL-1 beta to IL-1 alpha production during maturation of monocytes into inflammatory macrophages, and further emphasizes a dichotomy between IL-1 alpha and IL-1 beta.


2009 ◽  
Vol 297 (4) ◽  
pp. H1319-H1328 ◽  
Author(s):  
H. Glenn Bohlen ◽  
Wei Wang ◽  
Anatoliy Gashev ◽  
Olga Gasheva ◽  
Dave Zawieja

Multiple investigators have shown interdependence of lymphatic contractions on nitric oxide (NO) activity by pharmacological and traumatic suppression of endothelial NO synthase (eNOS). We demonstrated that lymphatic diastolic relaxation is particularly sensitive to NO from the lymphatic endothelium. The predicted mechanism is shear forces produced by the lymph flow during phasic pumping, activating eNOS in the lymphatic endothelium to produce NO. We measured [NO] during phasic contractions using microelectrodes on in situ mesenteric lymphatics in anesthetized rats under basal conditions and with an intravenous saline bolus (0.5 ml/100 g) or infusion (0.5 ml·100 g−1·h−1). Under basal conditions, [NO] measured on the tubular portions of the lymphatics was ∼200–250 nM, slightly higher than in the adjacent adipocyte microvasculature, whereas [NO] measured on the lymphatic bulb surface was ∼400 nM. Immunohistochemistry of eNOS in isolated lympathics indicated a much greater expression in the lymph valves and surrounding bulb area than in the tubular regions. During phasic lymphatic contractions, the valve and tubular [NO] increased with each contraction, and during intravenous saline infusion, [NO] increased in proportion to the contraction frequency and, presumably, lymph flow. The partial blockade of eNOS over ∼1 cm length with Nω-nitro-l-arginine methyl ester lowered the [NO]. These in vivo data document for the first time that both valvular and tubular lymphatic segments increase NO generation during each phasic contraction and that [NO] summated with increased contraction frequency. The combined data predict regional variations in eNOS and [NO] in the tubular and valve areas, plus the summated NO responses dependent on contraction frequency provide for a complex relaxation mechanism involving NO.


Nanoscale ◽  
2018 ◽  
Vol 10 (37) ◽  
pp. 17656-17662 ◽  
Author(s):  
Zhengqing Yan ◽  
Wei Bing ◽  
Chao Ding ◽  
Kai Dong ◽  
Jinsong Ren ◽  
...  

H2O2-free depots (CaO2/H-G@alginate) can produce hROS in situ through localized cascade reactions, damaging the main components of biofilms.


2019 ◽  
Vol 55 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Yufu Tang ◽  
Yuanyuan Li ◽  
Zhen Wang ◽  
Feng Pei ◽  
Xiaoming Hu ◽  
...  

A nitric-oxide-activatable organic semiconducting nanoprobe was developed forin vivo,in situ, real-time and non-invasive NIR-II fluorescence monitoring of drug-dose-dependent hepatotoxicity.


1998 ◽  
Vol 84 (1) ◽  
pp. 169-176 ◽  
Author(s):  
Xiao-Pei Gao ◽  
Syed R. Akhter ◽  
Israel Rubinstein

Gao, Xiao-Pei, Syed R. Akhter, and Israel Rubinstein.Ovalbumin increases macromolecular efflux from the in situ nasal mucosa of allergic hamsters. J. Appl. Physiol. 84(1): 169–176, 1998.—The purpose of this study was to determine whether bradykinin mediates ovalbumin-induced increase in macromolecular efflux from the nasal mucosa of ovalbumin-sensitized hamsters in vivo and, if so, whether thel-arginine/nitric oxide biosynthetic pathway transduces, in part, this response. We found that suffusion of ovalbumin onto the in situ nasal mucosa of ovalbumin-sensitized hamsters, but not of controls, elicited a significant time- and concentration-dependent increase in clearance of fluorescein isothiocyanate-labeled dextran (mol mass, 70 kDa; P < 0.05). HOE-140, but not des-Arg9,[Leu8]-bradykinin, and N G-l-arginine methyl ester (l-NAME), but not N G-d-arginine methyl ester, significantly attenuated ovalbumin-induced responses.l-Arginine, but notd-arginine, abolished the effects ofl-NAME.l-NAME also significantly attenuated bradykinin-, but not adenosine- induced increase in macromolecular efflux from the in situ nasal mucosa. Overall, these data suggest that ovalbumin increases macromolecular efflux from the in situ nasal mucosa of ovalbumin-sensitized hamsters, in part, by producing bradykinin with subsequent activation of thel-arginine/nitric oxide biosynthetic pathway.


1994 ◽  
Vol 267 (3) ◽  
pp. G416-G422 ◽  
Author(s):  
M. K. Mittal ◽  
T. K. Gupta ◽  
F. Y. Lee ◽  
C. C. Sieber ◽  
R. J. Groszmann

This study investigated whether nitric oxide (NO) plays a role in the intrahepatic portal circulation in normal rat livers perfused in situ. N omega-nitro-L-arginine (NNA), a specific NO biosynthesis inhibitor, significantly increased baseline portal pressure compared with controls (P < 0.05). Concentration-effect curves to norepinephrine (NE) were performed. Perfusate flow was maintained as constant, and perfusion pressure was continuously measured. NNA markedly enhanced the responsiveness to NE. This effect was abolished by the addition of L-arginine, a specific NO substrate. Presence of indomethacin did not alter the response to NE. The response to NE in the presence of indomethacin and NNA was significantly more than the response to NE in the presence of NNA alone. In vivo, intraportal infusion of NNA significantly enhanced the portal pressure compared with vehicle. This study demonstrates that NO contributes to the basal vascular tone and attenuates the response to NE in intrahepatic portal vascular bed of normal rats. These results support a functional role of NO in the regulation of the intrahepatic portal circulation in normal rats. This study also suggests a synergistic, albeit limited, role of prostacyclin in the intrahepatic circulation.


2003 ◽  
pp. 227-238
Author(s):  
Pei Tsai ◽  
Supatra Porasuphatana ◽  
Howard J. Halpern ◽  
Eugene D. Barth ◽  
Gerald M. Rosen

2000 ◽  
Vol 68 (8) ◽  
pp. 4653-4657 ◽  
Author(s):  
Alain P. Gobert ◽  
Sylvie Daulouede ◽  
Michel Lepoivre ◽  
Jean Luc Boucher ◽  
Bernard Bouteille ◽  
...  

ABSTRACT Nitric oxide (NO) is an important effector molecule of the immune system in eliminating numerous pathogens. Peritoneal macrophages fromTrypanosoma brucei brucei-infected mice express type II NO synthase (NOS-II), produce NO, and kill parasites in the presence ofl-arginine in vitro. Nevertheless, parasites proliferate in the vicinity of these macrophages in vivo. The present study shows thatl-arginine availability modulates NO production. Trypanosomes use l-arginine for polyamine synthesis, required for DNA and trypanothione synthesis. Moreover, arginase activity is up-regulated in macrophages from infected mice from the first days of infection. Arginase competes with NOS-II for their common substrate, l-arginine. In vitro, arginase inhibitors decreased urea production, increased macrophage nitrite production, and restored trypanosome killing. In vivo, a dramatic decrease inl-arginine concentration was observed in plasma from infected mice. In situ restoration of NO production and trypanosome killing were observed when excess l-arginine, but notd-arginine or l-arginine plusN ω-nitro-l-arginine (a NOS inhibitor), was injected into the peritoneum of infected mice. These data indicate the role of l-arginine depletion, induced by arginase and parasites, in modulating the l-arginine–NO pathway under pathophysiological conditions.


2015 ◽  
Vol 112 (17) ◽  
pp. 5539-5544 ◽  
Author(s):  
Deserah D. Strand ◽  
Aaron K. Livingston ◽  
Mio Satoh-Cruz ◽  
John E. Froehlich ◽  
Veronica G. Maurino ◽  
...  

Cyclic electron flow (CEF) around photosystem I is thought to balance the ATP/NADPH energy budget of photosynthesis, requiring that its rate be finely regulated. The mechanisms of this regulation are not well understood. We observed that mutants that exhibited constitutively high rates of CEF also showed elevated production of H2O2. We thus tested the hypothesis that CEF can be activated by H2O2 in vivo. CEF was strongly increased by H2O2 both by infiltration or in situ production by chloroplast-localized glycolate oxidase, implying that H2O2 can activate CEF either directly by redox modulation of key enzymes, or indirectly by affecting other photosynthetic processes. CEF appeared with a half time of about 20 min after exposure to H2O2, suggesting activation of previously expressed CEF-related machinery. H2O2-dependent CEF was not sensitive to antimycin A or loss of PGR5, indicating that increased CEF probably does not involve the PGR5-PGRL1 associated pathway. In contrast, the rise in CEF was not observed in a mutant deficient in the chloroplast NADPH:PQ reductase (NDH), supporting the involvement of this complex in CEF activated by H2O2. We propose that H2O2 is a missing link between environmental stress, metabolism, and redox regulation of CEF in higher plants.


Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.


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