1.Effect of sodium bisulphate on the stability of octreotide acetate: compatibility study with dexamethasone injection
Kouichi Tanabe ; Jun Ohkubo ; Tomoaki Ikezaki ; Shohei Kitayama ; Yuki Tsuneda ; Atsumi Nitta ; Lisa Imamura ; Hideto To ; Masanari Shimada ; Nozomu Murakami ; Hidenori Kitazawa
Palliative Care Research 2013;8(2):177-183
Background: Although several dexamethasone phosphate preparations are commercially available and frequently administered with octreotide acetate, their compatibility remains unknown. Aim: We investigated the effect of pH and sodium bisulphate on the stability of octreotide acetate. Measurement design: Octreotide acetate percentage was measured 3 and 10 days after it was mixed with 2 dexamethasone phosphate preparations containing different concentrations of sodium bisulphate as an additive, and in one that did not contain sodium bisulphate. Solutions were also analysed after they were prepared using phosphate buffer to achieve pH values of 4.0, 7.0, and 9.0. The initial octreotide acetate concentration was 41.7 g/mL. High-performance liquid chromatography was used for measurement. Results: The octreotide acetate percentage in the mixture with dexamethasone phosphate without sodium bisulphate was maintained at 95% for up to 10 days. However, mixing octreotide acetate with the other 2 agents resulted in a significant decrease to 85%. The octreotide acetate percentage was <90% after sodium bisulphate-containing solution was stored at room temperature under light-protected conditions for 3 days. The percentage of octreotide acetate in the pH 7.0 solution was <90% three days after preparation; however, in the pH 4.0 solution, it was maintained at 95% for up to 10 days. Conclusions: Our results suggest that octreotide acetate is hydrolysed in the presence of sodium bisulphate, leading to a decrease in the percentage of octreotide acetate in the solution, which can be avoided using sodium bisulphate-free dexamethasone phosphate preparations.
2.Implantation of Bone Marrow Stromal Cell Sheets Derived from Old Donors Supports Bone Tissue Formation
Manabu AKAHANE ; Takamasa SHIMIZU ; Yusuke INAGAKI ; Tsutomu KIRA ; Takuya EGAWA ; Akinori OKUDA ; Tadanobu ONISHI ; Tomoaki IMAMURA ; Yasuhito TANAKA
Tissue Engineering and Regenerative Medicine 2018;15(1):89-100
The purpose of this study was to evaluate the osteogenesis ability of osteogenic matrix cell sheets (OMCS) derived from old donor cells. Bone marrow stromal cells (BMSC) were obtained from young (7-week-old) and old (1-year-old) Fischer344 rats donors and cultured with modified Eagle's medium (MEM group) alone or containing dexamethasone (Dex; 10 nM) and ascorbic acid phosphate (AscP; 0.28 mM) (Dex/AscP group). We prepared four in vitro experimental groups: (1) young MEM, (2) young Dex/AscP, (3) old MEM and (4) old Dex/AscP. Cell proliferation and osteogenic marker mRNA expression levels were evaluated in vitro. To assess bone formation in vivo, the cells of each group were combined with beta tricalcium phosphate (TCP) disks followed by implantation in recipient rats. The in vitro study showed significant differences in the mRNA expression of osteocalcin, ALP, and BMP2 between MEM and Dex/AscP groups. Bone formation following implantation was observed upon histological analyses of all groups. TCP combined with OMCS (OMCS/TCP group) resulted in enhanced bone formation compared to that following combination with BMSC (BMSC/TCP). The osteocalcin content of the OMCS/TCP group 4 weeks after implantation was significantly higher than that in the BMSC/TCP construct for both young and old donors. The present study clearly indicated that OMCS could be generated from BMSCs of old as well as young donors using a mechanical retrieval method. Thus, through its usage of OMCS, this method may represent a potentially effective therapeutic option for cell-based therapy in elderly patients.
Aged
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Animals
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Ascorbic Acid
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Bone and Bones
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Bone Marrow
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Cell Proliferation
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Dexamethasone
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Humans
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In Vitro Techniques
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Mesenchymal Stromal Cells
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Methods
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Osteocalcin
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Osteogenesis
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Rats
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RNA, Messenger
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Tissue Donors
3.Impact of Temperature in Summer on Emergency Transportation for Heat-Related Diseases in Japan.
Yukie ITO ; Manabu AKAHANE ; Tomoaki IMAMURA
Chinese Medical Journal 2018;131(5):574-582
BackgroundIn Japan, the demand for emergency transportation for people with heat-related illness has recently increased. The purpose of this study was to investigate the relationship between incidents of heat-related illness and the daily maximum temperature.
MethodsThe daily maximum temperatures in Japan's 11 districts over the past 10 years were classified into four categories, with cutoff points at the 50, 75, 95, and higher than 95percentiles. We then conducted a logistic regression analysis of emergency transportation demand in each temperature category by age group, using the 50percentile as the reference category for each area.
ResultsThere were 42,931 cases of emergency transportation due to heat-related diseases during the study period. Classified by age, 12.5%, 43.4%, and 44.1% of cases involved children, adults, and elderly people, respectively. The analysis showed that the number of cases of emergency transportation for people with heat-related diseases (per 100,000 people; corresponding to a 1.0°C increase in the daily maximum temperature) was 0.016-0.106 among children (24.9-169.9 children required emergency transportation for heat-related diseases), from 0.013 to 0.059 among adults (19.8-98.2 adults required emergency transportation), and from 0.045 to 0.159 among elderly persons (30.0-145.4 elderly people required emergency transportation). The risk was highest for elderly persons, followed by children and finally adults. Cases of emergency transportation due to heat-related illness increased by 2.4-8.9 times when the daily maximum temperature was approximately 1.5°C above the mean daily maximum temperature. In fact, the daily maximum temperature had a larger effect than the daily relative humidity level on emergency transportation for people with heat-related diseases.
ConclusionPublic health organizations and health-care services should support elderly people and children, two high-risk groups for heat-related diseases.