Alloplastic injectable biomaterials for soft tissue augmentation: a report on two cases with complications associated with a new material (DermaLive) and a review of the literature

A wide variety of biological and alloplastic injectable biomaterials are available for soft tissue augmentation, but the ideal material has not yet been discovered. Biological materials such as collagen and hyaluronan yield temporary results, while injectable alloplasts are apt to cause varying degrees of foreign body reactions that may result in lumps and chronic inflammation.We present two cases (one is the first filed case in the world) of migratory subcutaneous inflammatory masses secondary to injection of acrylic hydrogel (DermaLive), which is an alloplastic biomaterial recently introduced into the market in Europe. Histology revealed foreign body reaction to acrylic hydrogel with granuloma formation containing multinucleated giant cells. Following this, further reports on complications have been reported elsewhere in Europe. The use and development of injectable materials, as well as alternative methods and future directions are reviewed.     

Endogenous tumor necrosis factor exerts its protective function intracellularly against the cytotoxicity of exogenous tumor necrosis factor.

Based on the findings that expression of endogenous tumor necrosis factor (enTNF), which is not present in TNF-susceptible cells, was generally observed in TNF-resistant cells and that TNF gene transfection gives rise to TNF resistance, the assumption was made that enTNF may be a protective protein against the cytotoxicity of exogenous TNF. However, it remains unknown whether the protection by enTNF is exerted in an intracellular or extracellular (autocrine) manner. We therefore transfected a nonsecretory human TNF gene (pTNF delta pro) into highly TNF-sensitive mouse tumorigenic fibroblasts (L-M cells) and investigated their TNF susceptibility. The transfectants expressed enTNF which was not secreted into the medium and acquired an appreciable degree of resistance to exogenous TNF. A significant increase in the manganous superoxide dismutase level was also noted in the transfectants. These findings suggest that enTNF exerts its protective function intracellularly by inducing manganous superoxide dismutase production.     

Human papillomaviruses and small cell carcinoma of the uterine cervix.

The in vitro DNA amplification technique of polymerase chain reaction was used to evaluate the possible presence of human papillomavirus (HPV) in small cell carcinoma of the uterine cervix. None of the 12 cases examined contain detectable amounts of either HPV type 16, 18, 31, or 33 DNA. On the other hand, HPV types 16 and 18 DNA were found in 14 (93.3%) and 9 (60.0%) of 25 invasive cervical squamous carcinoma tissues. The results seem to suggest that these types of HPV are not present or are present in extremely small quantities in cervical small cell carcinoma. Such an absence of HPV DNA makes it unlikely that these types of HPV play any etiological role in the pathogenesis of cervical small cell carcinoma.     

Kinetics of bactericidal and sporicidal effects of a disinfectant against bacteria isolated from hospital units]

The bactericidal and sporicidal activities of a peracetic acid disinfectant commonly used in hospitals (Acetoper 200) was studied using three bacterial species recovered in water from hemodialysis machines and humidifiers, i.e., Pseudomonas aeruginosa, Serratia liquefaciens, and Bacillus subtilis (spores). The method used was derived from AFNOR norms NF T 72-151 and NF T 72-231. For each strain, three concentrations of disinfectant were tested. Counts were performed every five minutes for one hour to evaluate killing kinetics. For both Gram-negative organisms, survival curves were biphasic, whereas B. subtilis counts decreased logarithmically. Both concentration and time influenced the 5 log10 decrease in counts. With S. liquefaciens and B. subtilis (spores), the 5 log10 decrease was not reached with low levels of disinfectant. In every case, the D value decreased substantially with increasing levels of disinfectant.     

Corticofugal modulation of the information processing in the auditory thalamus of the cat

Summary Single unit activity of 355 cells was recorded in the auditory thalamus of anesthetized cats before, during, and after the inactivation by cooling of the ipsilateral primary auditory cortex (AI). Most of the units (n = 288) showed similar functional characteristics of firing before and after the cryogenic blockade of AI. The spontaneous firing rate remained unchanged by cooling in 20% of the units and decreased in the majority of them (60%). In some regions, i.e. dorsal division of the medial geniculate body (MGB), lateral part of the posterior group of the thalamus, and auditory sector of the reticular nucleus of the thalamus, the maximum firing rate evoked by white noise bursts was generally affected by cooling in the same direction and to the same extent as the spontaneous activity. Units in the ventral division of MGB showed a characteristic increase of signal-to-noise ratio during cortical cooling. The corticofugal modulation led to the appearance or disappearance of the best frequency of tuning in 51 units and changed it by more than 0.5 octave in 34 units. The bandwidths of different response patterns to pure tones stimulation were used to define a set of functional properties. During cryogenic blockade of AI, two cortically modulated sub-populations of units were usually distinguished that exhibited changes for a given functional property. The complexity and diversity of the effects of cortical inactivation suggest that the corticothalamic projection may be the support for selective operations such as an adaptive filtering of the incoming acoustic signal at the thalamic level adjusted as a function of cortical activity.     

Glucocorticoids Decrease Hippocampal and Prefrontal Activation during Declarative Memory Retrieval in Young Men

Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval. Therefore, we tested memory retrieval in 21 young healthy males in a randomized placebo-controlled crossover design. Participants encoded word lists containing neutral and emotional words 1 h prior to ingestion of 20 mg hydrocortisone. Memory retrieval was tested using an old/new recognition paradigm in a rapid event-related design. It was found that hydrocortisone decreased brain activity in both the hippocampus and PFC during successful retrieval of neutral words. These observations are consistent with previous animal and human studies suggesting that glucocorticoids modulate both hippocampal and prefrontal brain regions that are crucially involved in memory processing. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Central and peripheral control of postprandial pyloric motility by endogenous opiates and cholecystokinin in dogs

The role of endogenous opiates and cholecystokinin (CCK) in the control of postprandial pyloric myoelectric activity was investigated in conscious dogs with chronically implanted intraparietal electrodes at the gastroduodenal junction. Meals consisted of either 20 g/kg of canned food (standard meal) or the same food supplemented with 0.5 mL/kg of arachis oil (fat meal). During the 6 hours after standard and fat meals, the number of pyloric spike bursts, 2-4 seconds in duration, was 61.8 +/- 15.8 and 49.9 +/- 12.7/15 minutes, respectively. Administered 15 minutes before a fat meal, naloxone (50 micrograms/kg IV) decreased the number of spike bursts by 31.4%, whereas methyl-levallorphan, a peripheral opiate antagonist, increased postprandial spike activity by 22.2% when administered IV (0.5 mg/kg) and decreased it when administered intracerobroventricularly at a dose of 10 micrograms/kg. These two antagonists administered in the same conditions before a standard meal had no effect on the postprandial spike activity. A 1-hour infusion of cholecystokinin octapeptide (CCK-8), 500 ng.kg-1.h-1 IV and 50 ng.kg-1.h-1 intracerebroventricularly, performed 1 hour after a standard meal induced a 19.6% and 15.8% decrease in the number of pyloric spike bursts, respectively. Both naloxone IV (50 micrograms/kg) and methyl-levallorphan intracerebroventricularly (10 micrograms/kg) administered before the infusion of CCK-8 reinforced this pyloric inhibition, which was antagonized by methyl-levallorphan IV (0.5 mg/kg). The CCK antagonist asperlicin, 200 micrograms/kg IV and 20 micrograms/kg intracerebroventricularly, administered before a fat meal increased pyloric spike bursts by 22.0% and 31.5%, respectively. These results indicate that after a fat meal, endogenous opiates exert a peripheral inhibitory and central stimulatory control of pyloric motility; they suggest the involvement of both peripheral and central release of CCK.