Therapy of Virus-Infected Plants by Heat Treatment I. Some Properties of Tomato Aspermy Virus and Its Inactivation at 36°C

1974 ◽  
Vol 22 (3) ◽  
pp. 437 ◽  
Author(s):  
GR Johnstone ◽  
GC Wade

An isolate of tomato aspermy virus (TAV) was inactivated both in vivo and in vitro at 36°C. Inactivation took the form of a second or higher order reaction, which indicated that loss of infectivity was not due solely to a direct effect of high temperature on the virus. The concentration of polyphenoloxidases increased greatly in tobacco plants grown at 36°C, and evidence was obtained to indicate that this enzyme class, either directly or indirectly, enhanced the inactivation of TAV during heat treatment. The concentration of ribonucleases also increased in heat-treated tissues and these may have aided the inactivation, as the infectivity of TAV was shown to be destroyed by RNase in tests in vitro. The pH and ionic strength of the sap decreased in heated plants and these changes may have been significant as TAV had critical requirements of buffer pH and molarity for optimum infectivity. The alterations in cellular metabolism responsible for these changes result from heat-induced stress. Therefore, the optimum temperature for therapy of many viruses by heat treatment is likely to vary with the host in which it is treated, depending upon the host's heat tolerance.

2007 ◽  
Vol 342-343 ◽  
pp. 545-548
Author(s):  
Li Ping Wang ◽  
Bang Cheng Yang ◽  
Ji Yong Chen ◽  
Xing Dong Zhang

The bioactivities of titanium oxide film on titanium surface received from different chemical treatment methods were studied in SBF in vitro and mechanically and histologically investigated in vivo. Three groups of titanium specimens were prepared: untreated titanium(S), acid-alkali treated titanium (H), and acid-alkali and heat-treated titanium(X). The oxide film of X surface resulted in more apatite formation and significantly higher strength of the interface between the samples and bone than those of the other titanium groups. The surface of the acid-alkali treated titanium and that further treated by heat treatment had higher bioactivity and stronger bone-bonding ability.


1995 ◽  
Vol 74 (03) ◽  
pp. 868-873 ◽  
Author(s):  
Silvana Arrighi ◽  
Roberta Rossi ◽  
Maria Giuseppina Borri ◽  
Vladimir Lesnikov ◽  
Marina Lesnikov ◽  
...  

SummaryTo improve the safety of plasma derived factor VIII (FVIII) concentrate, we introduced a final super heat treatment (100° C for 30 min) as additional virus inactivation step applied to a lyophilized, highly purified FVIII concentrate (100 IU/mg of proteins) already virus inactivated using the solvent/detergent (SID) method during the manufacturing process.The efficiency of the super heat treatment was demonstrated in inactivating two non-lipid enveloped viruses (Hepatitis A virus and Poliovirus 1). The loss of FVIII procoagulant activity during the super heat treatment was of about 15%, estimated both by clotting and chromogenic assays. No substantial changes were observed in physical, biochemical and immunological characteristics of the heat treated FVIII concentrate in comparison with those of the FVIII before heat treatment.


Author(s):  
Fatima Aerts-Kaya

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.


Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1424
Author(s):  
Seyeon Oh ◽  
Myeongjoo Son ◽  
Joonhong Park ◽  
Donghwan Kang ◽  
Kyunghee Byun

Rosacea is a skin inflammatory condition that is accompanied by not only redness and flushing but also unseen symptoms, such as burning, stinging, and itching. TRPV1 expression in UVB-exposed skin can lead to a painful burning sensation. Upregulated TRPV1 expression helps release neuropeptides, including calcitonin gene-related peptide, pituitary adenylate cyclase-activating polypeptide, and vasoactive intestinal peptide, which can activate macrophage and inflammatory molecules. In this study, we found that radiofrequency (RF) irradiation reduced TRPV1 activation and neuropeptide expression in a UVB-exposed in vivo model and UVB- or heat-treated in an in vitro model. RF irradiation attenuated neuropeptide-induced macrophage activation and inflammatory molecule expression. Interestingly, the burning sensation in the skin of UVB-exposed mice and patients with rosacea was significantly decreased by RF irradiation. These results can provide experimental and molecular evidence on the effective use of RF irradiation for the burning sensation in patients with rosacea.


Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 963
Author(s):  
Maria C. Holeva ◽  
Athanasios Sklavounos ◽  
Rajendran Rajeswaran ◽  
Mikhail M. Pooggin ◽  
Andreas E. Voloudakis

Cucumber mosaic virus (CMV) is a destructive plant virus with worldwide distribution and the broadest host range of any known plant virus, as well as a model plant virus for understanding plant–virus interactions. Since the discovery of RNA interference (RNAi) as a major antiviral defense, RNAi-based technologies have been developed for plant protection against viral diseases. In plants and animals, a key trigger of RNAi is double-stranded RNA (dsRNA) processed by Dicer and Dicer-like (DCL) family proteins in small interfering RNAs (siRNAs). In the present study, dsRNAs for coat protein (CP) and 2b genes of CMV were produced in vitro and in vivo and applied onto tobacco plants representing a systemic solanaceous host as well as on a local host plant Chenopodium quinoa. Both dsRNA treatments protected plants from local and systemic infection with CMV, but not against infection with unrelated viruses, confirming sequence specificity of antiviral RNAi. Antiviral RNAi was effective when dsRNAs were applied simultaneously with or four days prior to CMV inoculation, but not four days post inoculation. In vivo-produced dsRNAs were more effective than the in vitro-produced; in treatments with in vivo dsRNAs, dsRNA-CP was more effective than dsRNA-2b, while the effects were opposite with in vitro dsRNAs. Illumina sequencing of small RNAs from in vivo dsRNA-CP treated and non-treated tobacco plants revealed that interference with CMV infection in systemic leaves coincides with strongly reduced accumulation of virus-derived 21- and 22-nucleotide (nt) siRNAs, likely generated by tobacco DCL4 and DCL2, respectively. While the 21-nt class of viral siRNAs was predominant in non-treated plants, 21-nt and 22-nt classes accumulated at almost equal (but low) levels in dsRNA treated plants, suggesting that dsRNA treatment may boost DCL2 activity. Taken together, our findings confirm the efficacy of topical application of dsRNA for plant protection against viruses and shed more light on the mechanism of antiviral RNAi.


2006 ◽  
pp. 48-57
Author(s):  
R. C. Ray

The study was conducted to determine the production in vitro and in vivo of cellulases by Botrydiplodia theobromae and Rhizopus oryzae. Isolates of these organisms were obtained from the postharvest decay of sweetpotato tubers. Results revealed that B. theobrornae and R. oryzae which were isolated from postharvest spoilage of sweetpotato tubers produced endo-13-1,4-glucanase and exo-V-1 ,4-glucanase in culture and in fungi-infected tissues of sweetpotato tubers. The optimum temperature and pH for cellulose synthesis and activity were 30°C and pH 6.5, respectively.


2011 ◽  
Vol 76 (3) ◽  
pp. C454-C461 ◽  
Author(s):  
Melissa G. Robbins ◽  
Gaby Andersen ◽  
Veronika Somoza ◽  
Bruce D. Eshelman ◽  
David M. Barnes ◽  
...  

2019 ◽  
Vol 140 (2) ◽  
pp. 469-471
Author(s):  
Yuping Xiong ◽  
Hanzhi Liang ◽  
Haifeng Yan ◽  
Beiyi Guo ◽  
Meiyun Niu ◽  
...  

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Akiko Obata ◽  
Eri Miura-Fujiwara ◽  
Akimitsu Shimizu ◽  
Hirotaka Maeda ◽  
Masaaki Nakai ◽  
...  

Ti-29Nb-13Ta-4.6Zr (TNTZ) alloy has excellent mechanical properties and bone conductivity. For dental application, TNTZ surfaces were converted to white oxidized layer by a simple heat treatment in air to achieve the formation of aesthetic surfaces. The oxidized layer formed by the heat treatment at 1000°C for 0.5 or 1 hr was whiter and joined to TNTZ substrate more strongly than that formed by the treatment at 900°C. The layer consisted of TiO2(rutile), TiNb2O7, and TiTa2O7and possessed ~30 μm in thickness for the sample heat-treated at 1000°C and ~10 μm for that heat-treated at 900°C. The surface average roughness and the wettability increased after the heat treatment. The spreading and proliferation level of mouse osteoblast-like cell (MC3T3-E1 cell) on the heat-treated sample were almost the same as those on as-prepared one. The cell spreading on TNTZ was better than those on pure titanium (CP Ti) regardless of the heat treatment for the samples. There was no deterioration in thein vitrocell compatibility of TNTZ after the oxidized layer coating by the heat treatment.


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