when was the first blood culture - neonate microbiology test done for patient 72107 until 01/2104?
select microbiologyevents.charttime from microbiologyevents where microbiologyevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 72107 ) and microbiologyevents.spec_type_desc = 'blood culture - neonate' and strftime('%y-%m',microbiologyevents.charttime) <= '2104-01' order by microbiologyevents.charttime asc limit 1