A safety and feasibility study of the use of 670 nm red light in premature neonates

OBJECTIVE

Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the retina affecting extremely preterm or low birth weight infants The aim of this study was to assess the feasibility and safety of 670 nm red light use in a neonatal intensive care unit.

STUDY DESIGN

Neonates <30 weeks gestation and <1150 g were enrolled within 48 h of birth. Data collected included cause of preterm delivery, Apgar scores and birthweight. 670 nm red light was administered for 15 min per day from a distance of 25 cm, delivering 9 J cm(-)(2), from the time of inclusion in the study until 34 weeks postmenstrual age. Infants were assessed daily for the presence of any skin burns or other adverse signs.

RESULT

Twenty-eight neonates were enrolled, seven 24 to 26 weeks and twenty-one 27 to 29 weeks gestation. The most common cause for preterm delivery was preterm labor (14/28) with five of these having evidence of chorioamnionitis. There were no skin burns or other documented adverse events. Entry into the study was readily achieved and treatment was well accepted by parents and nursing staff.

CONCLUSION

670 nm red light appears to be a safe and feasible treatment for further research in respect to ROP.

Modifications to a commercially available linear mass spectrometer for mass-resolved microscopy with the pixel imaging mass spectrometry (PImMS) camera

RATIONALE

Imaging mass spectrometry is a powerful analytical technique capable of accessing a large volume of spatially resolved, chemical data from two-dimensional samples. Probing the entire surface of a sample simultaneously requires a detector with high spatial and temporal resolutions, and the ability to observe events relating to different mass-to-charge ratios.

METHODS

A commercially available time-of-flight mass spectrometer, designed for matrix-assisted laser desorption/ionization (MALDI) analysis, was combined with the novel pixel imaging mass spectrometry (PImMS) camera in order to perform multi-mass, microscope-mode imaging experiments. A number of minor modifications were made to the spectrometer hardware and ion optics so that spatial imaging was achieved for a number of small molecules.

RESULTS

It was shown that a peak width of Δm50 %  <  1  m/z unit across the range 200 ≤ m/z  ≤  800 can be obtained while also achieving an optimum spatial resolution of 25 µm. It was further shown that these data were obtained simultaneously for all analytes present without the need to scan the experimental parameters.

CONCLUSIONS

This work demonstrates the capability of multi-mass, microscope-mode imaging to reduce the acquisition time of spatially distributed analytes such as multi-arrays or biological tissue sections. It also shows that such an instrument can be commissioned by effecting relatively minor modifications to a conventional commercial machine.