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Objectives: The lesion topography of medullary infarction (MI) is heterogeneous and its correlation with stroke etiology remains elusive. We aim to clarify the lesion pattern of MI and to assess its correlation with stroke etiology.Material and Methods: Of 1129 subjects with available DWI in SMART study (a multi-center trial concerning secondary stroke prevention in China) between April 2008 and December 2010, 43 patients with DWI confirmed MI (3.8%) were retrospectively evaluated. Lesions were categorized as lateral and medial medullary infarction (LMI and MMI, 33 and 10 subjects respectively) at 3 levels rostro-caudally and correlated with the stroke etiology. Clinical profiles and long-term prognosis were analyzed.Results: Large artery atherosclerosis, small vessel occlusion, cardiogenic embolism and artery dissection accounted for 29, 11, 1, and 2 infarcts, respectively. Large artery disease was the most common cause in LMI (24 of 33, 72.7%) whereas small vessel occlusion was not uncommon in MMI (5 of 10, 50.0%). Though the difference of infarct pattern between large artery atherosclerosis and small vessel occlusion was insignificant, two distinct lesion patterns were considered to be relevant: (1) Rostral MMI with continuous medial pontine infarctions were more likely attributed to small vessel occlusion than large artery atherosclerosis. Kameda et al. (2) MMI with ventral to dorsal extension were more often caused by large artery disease than small vessel occlusion. Median NIHSS at admission was 4. During a median follow-up of 17 months, 2 patients died and 2 experienced recurrent ischemic events, 39 of 41 subjects (95.1%) were functional independent (mRS 0–2).Conclusions: This multi-center study demonstrates that MI has distinct lesion pattern depending on various stroke etiologies and mechanisms. Future investigations with larger sample size should establish the lesion pattern of MI and validate its correlation with the stroke etiology and mechanisms, which might improve stroke management.

Petroleum pollution is a severe environmental issue. Comprehensively revealing the genetic backgrounds of hydrocarbon-degrading microorganisms contributes to developing effective methods for bioremediation of crude oil-polluted environments. Marine bacterium Achromobacter sp. HZ01 is capable of degrading hydrocarbons and producing biosurfactants. In this study, the draft genome (5.5 Mbp) of strain HZ01 has been obtained by Illumina sequencing, containing 5,162 predicted genes. Genome annotation shows that “amino acid metabolism” is the most abundant metabolic pathway. Strain HZ01 is not capable of using some common carbohydrates as the sole carbon sources, which is due to that it contains few genes associated with carbohydrate transport and lacks some important enzymes related to glycometabolism. It contains abundant proteins directly related to petroleum hydrocarbon degradation. AlkB hydroxylase and its homologs were not identified. It harbors a complete enzyme system of terminal oxidation pathway for n-alkane degradation, which may be initiated by cytochrome P450. The enzymes involved in the catechol pathway are relatively complete for the degradation of aromatic compounds. This bacterium lacks several essential enzymes for methane oxidation, and Baeyer-Villiger monooxygenase involved in the subterminal oxidation pathway and cycloalkane degradation was not identified. These results suggest that strain HZ01 degrades n-alkanes via the terminal oxidation pathway, degrades aromatic compounds primarily via the catechol pathway and cannot perform methane oxidation or cycloalkane degradation. Additionally, strain HZ01 possesses abundant genes related to the metabolism of secondary metabolites, including some genes involved in biosurfactant (such as glycolipids and lipopeptides) synthesis. The genome analysis also reveals its genetic basis for nitrogen metabolism, antibiotic resistance, regulatory responses to environmental changes, cell motility, and material transport. The obtained genome data provide us with a better understanding of hydrocarbon-degrading bacteria, which may contribute to the future design of rational strategies for bioremediation of petroleum-polluted marine environments.