Novel antilisterial bacteriocin licheniocin 50.2 from Bacillus licheniformis VPS50.2 isolated from soil sample.

AIM: To isolate and characterize bacteriocin, licheniocin 50.2, from soil bacteria identified as Bacillus licheniformis. METHODS AND RESULTS: The strain B. licheniformis VPS50.2 was identified as bacteriocin producer, effective against Gram-positive bacteria, including Listeria monocytogenes, methicillin-resistant Staphylococcus aureus (MRSA) and ß-haemolytic streptococci. The start of bacteriocin production coincides with the beginning of sporulation. Ammonium sulfate precipitation, chloroform extraction and ultrafiltration were used for bacteriocin purification. MALDI TOF/TOF mass spectrometry of purified sample detected the protein with molecular mass of 3253·209 Da. N-terminal sequencing recognized first 15 amino acids with the sequence: W E E Y N I I X Q L G N K G Q. We named the newly characterized bacteriocin as subclass II.3 bacteriocin, licheniocin 50·2. The bacteriocin activity was insensitive to lysozyme and proteinase K, heat stable after incubation at 100°C for 30 min and over wide range of pH (2-12). MICs of crude bacteriocin extract were determined for L. monocytogenes and MRSA. Time-kill study showed that licheniocin had bactericidal effect to L. monocytogenes. CONCLUSION: A novel, thermostable, pH-tolerant bacteriocin active against Gram-positive bacteria was isolated. SIGNIFICANCE AND IMPACT OF THE STUDY: Attributes of new, stable licheniocin 50.2 make it a promising agent for application as biopreservative in food industry.

Oculomotor, trochlear, and abducens nerves penetrated by cerebral vessels. Microanatomy and possible clinical significance.

Twenty formaldehyde-fixed brains were examined under the stereoscopic microscope. In 12 brains (60%), the oculomotor nerves were penetrated by the circumflex mesencephalic artery or by a branch of the perforating vessels of the posterior cerebral artery, either on one side (40%) or on both (20%). In one brain (5%), a particular relationship was noticed between the trochlear nerve and the superior cerebellar artery. The abducens nerves were penetrated by the corresponding pontine veins in three brains (15%). These anatomical findings might have important clinical implications.

[The posterior inferior cerebellar artery]. / Sur l'artère cérébelleuse inférieure postérieure.

The posterior inferior cerebellar artery has a curved course in the region of the medulla oblongata. Besides its frequent individual variations, this vessel exhibits three morphological types: in type 1 (the commonest type, i.e. more than 50% of the cases) it curves with its vertex turned upwards; in type 2, the posterior inferior cerebellar artery turns in a gentle arch on to the posterior surface of the medulla oblongata, so there is no real curve; in type 3, the posterior inferior cerebellar artery curves but its vertex turns downwards. In all of these cases, the artery is in close relationship with the last four cranial nerves. This relationship is most characteristic in the 1st and 3rd types. The morphological types could be recognised on the angiograms.

[Characteristics of the human lateral geniculate nucleus vascular network]. / Karakteristike vaskularne mreze humanog lateralnog genikulatnog jedra.

The blood supply of the lateral geniculate nucleus (LGN) was studied on ten human brains obtained at autopsy from patients of both sexes with no indication of either psychiatric and neurological disorders or trauma of CNS. The age range was form 30 to 50 years. The brain blood vessels-the basilar artery and the internal carotid artery were injected with a mixture of gelatin and Indian ink. Microdissection revealed that the arterial branches for the LGN arise from anterior choroidal artery and posterior cerebral artery through one of its central branches-lateral posterior choroidal artery. The morphology of arterial network was examined by the analysis of cleared paraffine sections. The arterial branches run in a dorsal to ventral direction of the nucleus, parallely with lines of projection and perpendicularly to the plane of the LGN laminae. Free anastomoses occur between these branches.

Anastomoses in the territory of the posterior cerebral arteries.

Anastomoses in the region of the posterior cerebral arteries were found in all of 40 brains examined. Anastomoses were channel-like, plexiform or combined. The former measured from 0.07 mm to 1.1 mm in diameter. They were most often found among the interpeduncular perforating vessels (71.2%), and between the branches of the posterior and anterior cerebral arteries (75.7%). The functional significance of the anastomoses is discussed.

Distribution of the occipital branches of the posterior cerebral artery. Correlation with occipital lobe infarcts.

The occipital branches of the posterior cerebral artery were examined in 31 human brains. The authors determined the origin, course, and region of supply of each occipital branch: the parieto-occipital, calcarine, posterior temporal, and common temporal arteries, as well as the lingual gyrus artery. These vessels were found in all the brains examined except the lingual gyrus artery, which was present in only 8.3%. The occipital branches were noted to supply variable cortical regions. In addition, they sometimes took part in irrigation of deep forebrain structures. It was concluded that occlusion of a certain occipital artery may cause varying clinical signs and symptoms in different patients. The neurologic deficits that may occur following the isolated occlusion of individual occipital branches of the posterior cerebral artery are discussed.