The cocaine user: the potential problem patient for rhinoplasty

The current popularity of cocaine use poses special hazards for the patient and the plastic surgeon during rhinoplasty. It is incumbent upon the surgeon to inquire preoperatively about possible recreational use of cocaine. As the preferred site of cocaine administration, the nasal septal mucosa is exposed to both the intense vasoconstrictive action of cocaine and the irritative effects of numerous contaminating additives. Pathologic changes in the septal mucosa should be recognized by preoperative rhinoscopy and evaluated by biopsy. In this series of 13 patients, fewer than half were properly identified as cocaine users during the preoperative consultation. Preoperative rhinoscopic findings varied from grossly unremarkable septal mucosa to visible perforation and microscopic evidence of granulomas, inflammation, and necrosis. Surgical complications consisted of localized septal collapse, delayed mucosal healing, and inadequate correction of septal deflection. Submucous resection and septoplasty should be avoided in patients with a known history of intranasal cocaine application. Although rhinoplasty can be safely performed in selected patients with a history of cocaine use, it may be extremely limited, unfeasible, or hazardous in those with significant mucosal and cartilaginous impairment as well as in those patients who refuse or are unable to relinquish the drug.     

Localization of sequences regulating ancestral and acquired sites of esterase6 activity in Drosophila melanogaster

We have broadly defined the DNA regions regulating esterase6 activity in several life stages and tissue types of D. melanogaster using P- element-mediated transformation of constructs that contain the esterase6 coding region and deletions or substitutions in 5' or 3' flanking DNA. Hemolymph is a conserved ancestral site of EST6 activity in Drosophila and the primary sequences regulating its activity lie between -171 and -25 bp relative to the translation initiation site: deletion of these sequences decrease activity approximately 20-fold. Hemolymph activity is also modulated by four other DNA regions, three of which lie 5' and one of which lies 3' of the coding region. Of these, two have positive and two have negative effects, each of approximately twofold. Esterase6 activity is present also in two male reproductive tract tissues; the ejaculatory bulb, which is another ancestral activity site, and the ejaculatory duct, which is a recently acquired site within the melanogaster species subgroup. Activities in these tissues are at least in part independently regulated: activity in the ejaculatory bulb is conferred by sequences between -273 and -172 bp (threefold decrease when deleted), while activity in the ejaculatory duct is conferred by more distal sequences between -844 and -614 bp (fourfold decrease when deleted). The reproductive tract activity is further modulated by two additional DNA regions, one in 5' DNA (-613 to -284 bp; threefold decrease when deleted) and the other in 3' DNA (+1860 to +2731 bp; threefold decrease when deleted) that probably overlaps the adjacent esteraseP gene. Collating these data with previous studies suggests that expression of EST6 in the ancestral sites is mainly regulated by conserved proximal sequences while more variable distal sequences regulate expression in the acquired ejaculatory duct site.      

Phylogenetic diversification of immunoglobulin genes and the antibody repertoire

Immunoglobulins are encoded by a large multigene system that undergoes somatic rearrangement and additional genetic change during the development of immunoglobulin-producing cells. Inducible antibody and antibody-like responses are found in all vertebrates. However, immunoglobulin possessing disulfide-bonded heavy and light chains and domain-type organization has been described only in representatives of the jawed vertebrates. High degrees of nucleotide and predicted amino acid sequence identity are evident when the segmental elements that constitute the immunoglobulin gene loci in phylogenetically divergent vertebrates are compared. However, the organization of gene loci and the manner in which the independent elements recombine (and diversify) vary markedly among different taxa. One striking pattern of gene organization is the "cluster type" that appears to be restricted to the chondrichthyes (cartilaginous fishes) and limits segmental rearrangement to closely linked elements. This type of gene organization is associated with both heavy- and light-chain gene loci. In some cases, the clusters are "joined" or "partially joined" in the germ line, in effect predetermining or partially predetermining, respectively, the encoded specificities (the assumption being that these are expressed) of the individual loci. By relating the sequences of transcribed gene products to their respective germ-line genes, it is evident that, in some cases, joined-type genes are expressed. This raises a question about the existence and/or nature of allelic exclusion in these species. The extensive variation in gene organization found throughout the vertebrate species may relate directly to the role of intersegmental (V<==>D<==>J) distances in the commitment of the individual antibody-producing cell to a particular genetic specificity. Thus, the evolution of this locus, perhaps more so than that of others, may reflect the interrelationships between genetic organization and function.      

Clinical trials of amniotic membranes in burn wound care

Four test conditions of increasing complexity were used to evaluate the clinical efficacy of amniotic membranes as biologic dressings on donor sites and burn wounds in children. These were the clean-skin donor-site wound, the uncontaminated shallow partial-thickness burn wound, the bed of freshly excised full-thickness wounds, and the granulating surface of colonized burn wounds. The rate of epithelialization under amniotic membranes was the same as that under 5% scarlet red ointment or 0.5% silver nitrate solution dressings. Preservation of a healthy excised wound bed and maintenance of a low bacterial count in contaminated wounds paralleled the experience with human allograft dressings despite technical difficulties and the absence of vascularization of amniotic membrane and its fragile structure. Tentative conclusions are drawn as to the mechanisms by which biologic dressings exert their beneficial effects.     

Characterization of the spontaneous murine B cell leukemia (BCL1). III. Evidence for monoclonality by using an anti-idiotype antibody.

We have raised an anti-idiotypic antibody against the cell surface IgM of the murine BCL1 tumor cells. This antiserum reacts exclusively with the IgM expressed on the tumor cells and detects a unique population of cells in the spleen and blood of the tumor-bearing mice. When these cells are stimulated in vitro with LPS, they secrete an IgM bearing the same idiotype as the cell surface Ig. These results are discussed in terms of a model for the immunotherapy of a chronic lymphocytic leukemia-like syndrome in mice.     

Induction of allograft tolerance after total lymphoid irradiation (TLI): development of suppressor cells of the mixed leukocyte reaction (MLR).

We searched for the presence of suppressor cells of the MLR in C57BL/Ka leads to BALB/c chimeras. The chimeras were made with total lymphoid irradiation (TLI) and marrow transplantation. Spleen cells from the old chimeras inhibited the MLR of BALB/c responder cells against C57BL/Ka stimulator cells. Inhibition was specific for the stimulator cells, since no effect on the MLR was observed with C3H or BALB.C3H stimulator cells. Maximal inhibition was achieved when the responder cells in the MLR shared the H-2 haplotype of the chimeric recipient. Spleen cells obtained from chimeras young 30 to 40 days after BM transplantation inhibited the MLR nonspecifically, since similar marked inhibition was observed regardless of the H-2 haplotype of the responder or stimulator cells. The finding of antigen-specific and nonspecific suppressor cells is similar to that observed in mice rendered tolerant to bovine serum albumin after treatment with TLI.     

Determination of phenylalanine in serum using reversed-phase liquid chromatography and fluorescence detection

A liquid chromatography procedure is reported for determining phenylalanine in small volumes of serum. A 10-μl volume of serum was deproteinized with ethanol and an aliquot was derivatized with dansyl chloride reagent. The dansylated phenylalanine and the norleucine internal standard were separated using reversed-phase chromatography and measured with a fluorescence detector. Linearity was excellent over the range 50–800 mg/l. Within-run precision was better than 4%. Total analysis time including chromatography was approximately 40 min. As little as 300 pg of dansylated phenylalanine was detected.     

Pseudocyst formation after rectus flap breast reconstruction: diagnosis and treatment

Pseudocyst is an unusual complication occurring after rectus flap breast reconstruction. Of four patients in whom a preoperative diagnosis of pseudocyst was made, three had epigastric masses and a fourth presented with a mass of the chest wall. The three patients with epigastric masses were identified by physical examination and evaluated by aspiration of cyst contents. Imaging with computed tomography delineated cyst anatomy and assisted in confirmation of the diagnosis. Most likely, the pathogenesis of these lesions is related to undrained or clinically undetected serous collections which ultimately form firm walls of fibrin. Although all the patients had ipsilateral rectus flap reconstructions, flap transposition does not appear to be causally related to any fluid accumulation. In one patient, a squamous carcinoma, probably arising from the original intraductal breast pathology, created physical and computed tomographic findings suggestive of pseudocyst. Therefore, confirmation of the diagnosis by biopsy, combined with excision, or, at least, biopsy of the anterior cyst wall is recommended in patients with this condition. All three patients with epigastric pseudocysts were explored. There have been no recurrences after an average of 28 months.     

The role of snail aestivation in transmission of schistosomiasis in changing climatic conditions

Schistosomiasis vector snails are subjected to extreme seasonal changes, particularly in ephemeral rivers and lentic waterbodies. In the tropics, aestivation is one of the adaptive strategies for survival and is used by snails in times of extremely high temperatures and desiccation. Aestivation therefore plays an important role in maintaining the transmission of schistosomiasis. This review assesses the possible impacts of climate change on the temporal and spatial distribution of schistosomiasis-transmitting snails with special emphasis on aestivation, and discusses the effect of schistosome infection on aestivation ability. The impacts of parasite development on snails, as well as physiological changes, are discussed with reference to schistosomiasis transmission. This review shows that schistosome-infected snails have lower survival rates during aestivation, and that those that survive manage to get rid of the infection. In general, snail aestivation ability is poor and survival chances diminish with time. Longer dry periods result in fewer, as well as uninfected, snails. However, the ability of the surviving snails to repopulate the habitats is high.     

Attenuation of pattern recognition receptor signaling is mediated by a MAP kinase kinase kinase

Pattern recognition receptors (PRRs) play a key role in plant and animal innate immunity. PRR binding of their cognate ligand triggers a signaling network and activates an immune response. Activation of PRR signaling must be controlled prior to ligand binding to prevent spurious signaling and immune activation. Flagellin perception in Arabidopsis through FLAGELLIN‐SENSITIVE 2 (FLS2) induces the activation of mitogen‐activated protein kinases (MAPKs) and immunity. However, the precise molecular mechanism that connects activated FLS2 to downstream MAPK cascades remains unknown. Here, we report the identification of a differentially phosphorylated MAP kinase kinase kinase that also interacts with FLS2. Using targeted proteomics and functional analysis, we show that MKKK7 negatively regulates flagellin‐triggered signaling and basal immunity and this requires phosphorylation of MKKK7 on specific serine residues. MKKK7 attenuates MPK6 activity and defense gene expression. Moreover, MKKK7 suppresses the reactive oxygen species burst downstream of FLS2, suggesting that MKKK7‐mediated attenuation of FLS2 signaling occurs through direct modulation of the FLS2 complex.