Membrane interactions and antimicrobial effects of layered double hydroxide nanoparticles

Membrane interactions are critical for the successful use of inorganic nanoparticles as antimicrobial agents and as carriers of, or co-actives with, antimicrobial peptides (AMPs). In order to contribute to an increased understanding of these, we here investigate effects of particle size (42-208 nm) on layered double hydroxide (LDH) interactions with both bacteria-mimicking and mammalian-mimicking lipid membranes. LDH binding to bacteria-mimicking membranes, extraction of anionic lipids, as well as resulting membrane destabilization, was found to increase with decreasing particle size, also translating into size-dependent synergistic effects with the antimicrobial peptide LL-37. Due to strong interactions with anionic lipopolysaccharide and peptidoglycan layers, direct membrane disruption of both Gram-negative and Gram-positive bacteria is suppressed. However, LDH nanoparticles cause size-dependent charge reversal and resulting flocculation of both liposomes and bacteria, which may provide a mechanism for bacterial confinement or clearance. Taken together, these findings demonstrate a set of previously unknown behaviors, including synergistic membrane destabilization and dual confinement/killing of bacteria through combined LDH/AMP exposure, of potential therapeutic interest.

Craniofacial morphology in twins with cleft lip and palate

The craniofacial morphology of 11 pairs of monozygotic (MZ) and 28 pairs of dizygotic (DZ) Finnish twins, discordant or concordant for cleft of the lip (CL), unilateral cleft lip and palate (UCLP), or cleft palate only (CP) were investigated by means of lateral cephalometric radiographs. The results were compared to those of age-, sex-, and cleft-type matched single-birth cleft subjects, and also with normative data from the Nordic population. The co-twins with no cleft lip or palate (NONC) showed only slightly more obtuse gonial and steeper mandibular angles compared to normative data. Twins with CL, UCLP or CP had a more retrusive mandible, a wider cranial base and mandibular angle, and a wider angle between the maxilla and mandible than did the single-birth cleft subjects. Comparison of the noncleft twin group with the CL, UCLP, and CP twin groups for the CL twins showed no significant differences. For the UCLP twins, a more retrusive and down- and backward rotation of both jaws, a wider gonial angle, and a wider cranial base angle was seen. The CP twins had their maxillae slightly retrusive, the down- and backward rotation of both jaws was apparent, and the gonial angle was more obtuse. A comparison between the noncleft MZ and noncleft CDZ twins showed no significant differences. The MZ CP twins had a more retrusive mandible and more down- and backward rotation of both jaws than did DZ CP twins. It thus can be suggested that twinning itself does not seem to have an effect on maxillofacial morphology, but the features of the mandibular structure, the cranial base angulation, and the inclination of the jaws are at least partly genetically induced.

Tissue expansion and flaps for surgical correction of male pattern baldness

The author describes how to use a long, non-delayed temporo-parieto-occipital (TPO) flap across the total frontal hairline, and tissue expansion for coverage of the bald area behind the flap. This concept can be used successfully in extensively bald patients where two TPO flaps would not be sufficient to cover the total bald area. An even growth of hair is achieved. When the hair "reserve" is good, quite dense hair can be reconstructed. The flap described is performed under local anaesthesia without delays and does not have the risk of postauricular necrosis sometimes seen with certain designs of TPO flaps.

Primary hereditary systemic amyloidosis (Meretoja's syndrome): clinical features and treatment by plastic surgery

The characteristic, bloodhound-like appearance, which degenerates gradually, of patients with primary hereditary systemic amyloidosis, also called Meretoja's syndrome (MS), is attributable to amyloid degeneration of the craniofacial skin and peripheral facial nerves, but apparently also to amyloid deposits in the muscles; a finding not previously described. A material of five patients treated with plastic surgery is presented, and the peculiarities and differences of this rare disease in comparison with other peripheral neuropathies is discussed from a reconstructive viewpoint.

Victims of assault attending casualty departments

Victims of assault make up about 8% of all adult injury cases. The purpose of this study was to analyse the personal characteristics and injuries of 518 victims of assault (=case material) and 496 accidentally injured (=controls), selected at random in a large casualty department. The proportion of males was higher among the assault cases than among controls (76 vs. 61%). Assault victims were more concentrated in the age range 15 to 44 years (81 vs. 64%). Fifty per cent of the cases and 8% of the controls were intoxicated, while the rates of chronic misuse of alcohol were 37 and 18%, respectively. Forty seven per cent of the cases and 18% of the controls arrived at night. Assault cases had sustained mostly minor head injuries. However, injuries needing referral to the ENT department or Dept. of jaw surgery were also common. Casualty departments are well suited to victim studies. Additional information as to social background, criminality and psychiatric morbidity of victims is needed.