scholarly journals Killing efficacy of a new hypothermic corneal storage medium against the micro-organisms frequently found in human donor cornea intended for transplantation

2021 ◽  
Vol 6 (1) ◽  
pp. e000833
Author(s):  
Laura Giurgola ◽  
Claudio Gatto ◽  
Claudia Honisch ◽  
Orietta Rossi ◽  
Eugenio Ragazzi ◽  
...  

ObjectiveTo study the in vitro killing efficacy of Kerasave (AL.CHI.MI.A Srl), a medium provided with amphotericin B tablet for hypothermic storage of human donor corneas, against relevant contaminants associated with postkeratoplasty infections.Methods and AnalysisThe antimicrobial activity of Kerasave was determined after 0, 3 and 14 days of incubation at 2°C–8°C, inoculating Kerasave and the control medium with 105–106 colony forming units (CFU) of Candida albicans (CA), Fusarium solani (FS), Aspergillus brasiliensis (AB), Staphylococcus aureus (SA), Enterococcus faecalis (EF), Bacillus subtilis spizizenii (BS), Pseudomonas aeruginosa (PA), Enterobacter cloacae (EC) and Klebsiella pneumoniae (KP). Log10 reductions at different time intervals were determined by assessing the number of viable CFU using the serial dilution plating technique.ResultsAfter 3 days, Kerasave induced the highest log10 decrease in the concentrations of KP, PA, CA and EC (5.37, 4.15, 2.97 and 2.67, respectively; all p<0.001). The log10 decreases of SA and EF were 2.27 and 2.11, respectively (all p<0.001). The lowest log10 decrease was observed in BS, AB and FS concentrations (0.25, 0.30 and 0.67, respectively; p<0.001 for BS and AB and p=0.004 for FS). After 14 days, the microbial count of CA, FS, SA, EF, PA and EC further decreased (p=0.006 for FS; p<0.001 for the others).ConclusionKerasave effectively reduced or kept unchanged the microbial concentration of almost all tested strains after 3 days. Thus, this novel medium represents a valuable tool to control the microbial contamination of human donor corneas during hypothermic storage for up to 14 days before transplantation.

Author(s):  
Michel Haagdorens ◽  
Elle Edin ◽  
Per Fagerholm ◽  
Marc Groleau ◽  
Zvi Shtein ◽  
...  

Abstract Purpose To determine feasibility of plant-derived recombinant human collagen type I (RHCI) for use in corneal regenerative implants Methods RHCI was crosslinked with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) to form hydrogels. Application of shear force to liquid crystalline RHCI aligned the collagen fibrils. Both aligned and random hydrogels were evaluated for mechanical and optical properties, as well as in vitro biocompatibility. Further evaluation was performed in vivo by subcutaneous implantation in rats and corneal implantation in Göttingen minipigs. Results Spontaneous crosslinking of randomly aligned RHCI (rRHCI) formed robust, transparent hydrogels that were sufficient for implantation. Aligning the RHCI (aRHCI) resulted in thicker collagen fibrils forming an opaque hydrogel with insufficient transverse mechanical strength for surgical manipulation. rRHCI showed minimal inflammation when implanted subcutaneously in rats. The corneal implants in minipigs showed that rRHCI hydrogels promoted regeneration of corneal epithelium, stroma, and nerves; some myofibroblasts were seen in the regenerated neo-corneas. Conclusion Plant-derived RHCI was used to fabricate a hydrogel that is transparent, mechanically stable, and biocompatible when grafted as corneal implants in minipigs. Plant-derived collagen is determined to be a safe alternative to allografts, animal collagens, or yeast-derived recombinant human collagen for tissue engineering applications. The main advantage is that unlike donor corneas or yeast-produced collagen, the RHCI supply is potentially unlimited due to the high yields of this production method. Lay Summary A severe shortage of human-donor corneas for transplantation has led scientists to develop synthetic alternatives. Here, recombinant human collagen type I made of tobacco plants through genetic engineering was tested for use in making corneal implants. We made strong, transparent hydrogels that were tested by implanting subcutaneously in rats and in the corneas of minipigs. We showed that the plant collagen was biocompatible and was able to stably regenerate the corneas of minipigs comparable to yeast-produced recombinant collagen that we previously tested in clinical trials. The advantage of the plant collagen is that the supply is potentially limitless.


2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
D. Camposampiero ◽  
S. Grandesso ◽  
E. Zanetti ◽  
S. Mazzucato ◽  
M. Solinas ◽  
...  

Aims. To compare HB&L and BACTEC systems for detecting the microorganisms contaminating the corneal storage liquid preserved at 31°C.Methods. Human donor corneas were stored at 4°C followed by preservation at 31°C. Samples of the storage medium were inoculated in BACTEC Peds Plus/F (aerobic microorganisms), BACTEC Plus Anaerobic/F (anaerobic microorganisms), and HB&L bottles. The tests were performed (a) after six days of storage, (b) end of storage, and (c) after 24 hours of preservation in deturgescent liquid sequentially. 10,655 storage and deturgescent media samples were subjected to microbiological control using BACTEC (6-day incubation) and HB&L (24-hour incubation) systems simultaneously. BACTEC positive/negative refers to both/either aerobic and anaerobic positives/negatives, whereas HB&L can only detect the aerobic microbes, and therefore the positives/negatives depend on the presence/absence of aerobic microorganisms.Results. 147 (1.38%) samples were identified positive with at least one of the two methods. 127 samples (134 identified microorganisms) were positive with both HB&L and BACTEC. 14 HB&L+/BACTEC− and 6 BACTEC+/HB&L− were identified. Sensitivity (95.5%), specificity (99.8%), and positive (90.1%) and negative predictive values (99.9%) were high with HB&L considering a 3.5% annual contamination rate.Conclusion. HB&L is a rapid system for detecting microorganisms in corneal storage medium in addition to the existing methods.


2005 ◽  
Vol 60 (2) ◽  
pp. 305-308 ◽  
Author(s):  
Stephan Reichl ◽  
Stefanie Döhring ◽  
Jürgen Bednarz ◽  
Christel C. Müller-Goymann

1971 ◽  
Vol 68 (1_Suppl) ◽  
pp. S27-S40 ◽  
Author(s):  
T. Kobayashi ◽  
T. Kigawa ◽  
M. Mizuno ◽  
T. Watanabe

ABSTRACT There are several in vitro methods to analyse the function of the adenohypophysis or the mechanisms of its regulation. The present paper deals with single cell culture, organ culture and short term incubation techniques by which the morphology and gonadotrophin-secreting function of the adenohypophysis were studied. In trypsin-dispersed cell culture, the adenohypophysial cells showed extensive propagation to form numerous cell colonies and finally develop into a confluent monolayer cell sheet covering completely the surface of culture vessels. Almost all of the cultured cells, however, became chromophobic, at least at the end of the first week of cultivation, when gonadotrophin was detectable neither in the culture medium nor in the cells themselves. After the addition of the hypothalamic extract, gonadotrophin became detectable again, and basophilic or PAS-positive granules also reappeared within the cells, suggesting that the gonadotrophs were stimulated by the extract to produce gonadotrophin. In organ culture and short term incubation, the incorporation of [3H] leucine into the adenohypophysial cells in relation to the addition of hypothalamic extract was examined. It was obvious that the ability to incorporate [3H] leucine into the gonadotrophs in vitro was highly dependent upon the presence of the hypothalamic extract.


2020 ◽  
Vol 13 (11) ◽  
pp. 1
Author(s):  
A. R. B. Zanco ◽  
A. Ferreira ◽  
G. C. M. Berber ◽  
E. N. Gonzaga ◽  
D. C. C. Sabino

The different integrated production systems can directly interfere with its bacterial community. The present study aimed to assess density, bacterial diversity and the influence of dry and rainy season in different integrated and an exclusive production system. The fallow and a native forest area was assessed to. Samples were collected in 2012 March and September. The isolation were carried out into Petri dishes containing DYGS medium. The number of colony forming units (CFU) was counted after 48 hours and. The bacterial density ranged between 106 and 107 CFU g-1 soil. The crop system affected the dynamics of the bacterial community only in the rainy season. The rainy season showed greater density of total bacteria when compared to the dry period regardless of the cropping system. The dendrograms with 80 % similarity showed thirteen and fourteen groups in the rainy and dry seasons. Isolates with the capacity to solubilize phosphate in vitro were obtained from all areas in the two seasons, but this feature has been prevalent in bacteria isolated during the rainy season


Author(s):  
Sudarshan Singh ◽  
Ayaz Ahmad ◽  
Sunil Bothara B

The present study was taken to formulate and evaluate mucilage obtained from Buchanania lanzan spreng seeds (BL) belonging to family anacardiacea for oral mucoadhesive drug delivery system containing losartan potassium. Physiochemical characteristics of mucilage, such as swelling index, microbial count, viscosity, hydration capacity, flow property, and pH were studied. The mucilage was evaluated for its mucoadhesive properties in compressed tablet, containing losartan potassium. Granules were prepared by wet granulation process using polyvinylpyrrolidone as binding agent. Mucilage was used in four different concentrations i.e., 21, 42 and 55% w/w. The tablet were prepared and evaluated for its physical property. Further, in vitro dissolution and swelling index was determined. The property of bioadhesive strength of isolated mucilage was compared with Guar gum and HPMC E5LV, which was used as standard mucoadhesive agent concentration. Bioadhesive strength of the tablet was measured on the modified physical balance. Result revealed that tablets had good physiochemical properties, and drug release was retarded as concentration of mucilage was increased. The force of adhesion was obtained 0.1238N, 0.2822N, 0.5175N, 0.8679N and 0.3983N respectively for F1, F2, F3, F4 and F5. Formulations were subjected for study the effect of agitation at different rpm. Formulation showed relative effect on release of drug from formulation. All the formulations were subjected to stability studies for three months, all formulations showed stability with respect to release pattern. In conclusions, these results indicate that the seed mucilage of BL can be a suitable excipient for oral mucoadhesive drug delivery systems.  


2020 ◽  
Vol 27 (29) ◽  
pp. 4840-4854 ◽  
Author(s):  
Chrysoula-Evangelia Karachaliou ◽  
Hubert Kalbacher ◽  
Wolfgang Voelter ◽  
Ourania E. Tsitsilonis ◽  
Evangelia Livaniou

Prothymosin alpha (ProT&#945;) is a highly acidic polypeptide, ubiquitously expressed in almost all mammalian cells and tissues and consisting of 109 amino acids in humans. ProT&#945; is known to act both, intracellularly, as an anti-apoptotic and proliferation mediator, and extracellularly, as a biologic response modifier mediating immune responses similar to molecules termed as “alarmins”. Antibodies and immunochemical techniques for ProT&#945; have played a leading role in the investigation of the biological role of ProT&#945;, several aspects of which still remain unknown and contributed to unraveling the diagnostic and therapeutic potential of the polypeptide. This review deals with the so far reported antibodies along with the related immunodetection methodology for ProT&#945; (immunoassays as well as immunohistochemical, immunocytological, immunoblotting, and immunoprecipitation techniques) and its application to biological samples of interest (tissue extracts and sections, cells, cell lysates and cell culture supernatants, body fluids), in health and disease states. In this context, literature information is critically discussed, and some concluding remarks are presented.


Blood ◽  
1978 ◽  
Vol 51 (3) ◽  
pp. 539-547 ◽  
Author(s):  
DH Chui ◽  
SK Liao ◽  
K Walker

Abstract Erythroid progenitor cells in +/+ and Sl/Sld fetal livers manifested as burst-forming units-erythroid (BFU-E) and colony-forming units- erythroid (CFU-E) were assayed in vitro during early development. The proportion of BFU-E was higher as mutant than in normal fetal livers. On the other hand, the proportion of CFU-E was less in the mutant than in the normal. These results suggest that the defect in Sl/Sld fetal hepatic erythropoiesis is expressed at the steps of differentiation that effect the transition from BFU-E to CFU-E.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2574
Author(s):  
Lahcen Hssaini ◽  
Francisca Hernandez ◽  
Manuel Viuda-Martos ◽  
Jamal Charafi ◽  
Rachid Razouk ◽  
...  

In the present study, chromatic coordinates, phenolic acids, flavonoids and antioxidant capacity assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS) and lipid peroxidation inhibition capacity (LPIC) essays and their relative IC50 were investigated in 25 fig cultivars growing in Morocco. The aims of this study were to determine (i) the variation in these compounds among light and dark-colored cultivars, (ii) their partitioning between fruit peel and pulp and (iii) to display network connections among these variables. Twelve phenolic compounds (PCs) were isolated in peel extract versus eight in pulp samples. Anthocyanins, mainly cyanidin-3,5-diglucoside and cyanidin-3-O-rutinoside, were the predominant compounds in peels, where the mean concentrations were 75.90 ± 18.76 and 77.97 ± 18.95 µg/g dw, respectively. On the other hand, (−)-epicatechin and cyanidin-3-O-rutinoside were the major compounds in the pulp extracts, where the mean values were 5.23 ± 4.03 and 9.01 ± 5.67 µg/g dw, respectively. A two-dimensional hierarchically clustered heatmap was applied to the dataset to explore correlations in the dataset and similarities between cultivars, without dimensionality reduction. Results showed that anthocyanins, particularly pelargonidin-3-O-rutinoside, cyanidin-3,5-diglucoside and cyanidin-3-O-rutinoside, were the main contributors to the peels’ free radical scavenging capacity. This capacity was particularly higher in the peel of dark-colored figs compared to the fruit pulp. The local cultivar “INRA 1301” showed the most promising phenolic profile due to its very high levels of almost all detected PCs, especially (−)-epicatechin, quercetin-3-O-rutinoside, quercetin-3-O-glucoside, cyanidine-3,5-diglucoside, cyanidine-3-O-rutinoside and pelargonidin-3-O-rutinoside (54.66, 141.08, 35.48, 494.08, 478.66, 12.56 µg/g dw, respectively). Having the darkest figs in the collection (L* = 25.72, c* = 22.09 and h° = 20.99), this cultivar has also combined promising IC50 values, which were of 19.85, 40.58 and 124.78 µg/mL for DPPH, ABTS and LPIC essays, respectively.


Diversity ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 197
Author(s):  
Tao Wang ◽  
Miao Chi ◽  
Ling Guo ◽  
Donghuan Liu ◽  
Yu Yang ◽  
...  

Root-associated endophytic fungi (RAF) are found asymptomatically in almost all plant groups. However, little is known about the compositions and potential functions of RAF communities associated with most Orchidaceae species. In this study, the diversity of RAF was examined in four wild epiphytic orchids, Acampe rigida, Doritis pulcherrima, Renanthera coccinea, and Robiquetia succisa, that occur in southern China. A culture-independent method involving Illumina amplicon sequencing, and an in vitro culture method, were used to identify culturable fungi. The RAF community diversity differed among the orchid roots, and some fungal taxa were clearly concentrated in a certain orchid species, with more OTUs being detected. By investigating mycorrhizal associations, the results showed that 28 (about 0.8%) of the 3527 operational taxonomic units (OTUs) could be assigned as OMF, while the OTUs of non-mycorrhizal fungal were about 99.2%. Among the OMFs, Ceratobasidiaceae OTUs were the most abundant with different richness, followed by Thelephoraceae. In addition, five Ceratobasidium sp. strains were isolated from D. pulcherrima, R. succisa, and R. coccinea roots with high separation rates. These culturable Ceratobasidium strains will provide materials for host orchid conservation and for studying the mechanisms underlying mycorrhizal symbiosis.


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