Bovine Colostrum miR-30a-5p Targets the NF-κB Signaling Pathway to Alleviate Inflammation in Intestinal Epithelial Cells

Inflammatory bowel disease (IBD) is a common disease of the digestive system, and an excessive immune response mediated by the nuclear factor κ-B (NF-κB) signaling pathway is an essential etiology. Recent studies have found that bovine milk exosomes can improve intestinal mucosal health by delivering microRNA (miRNA), but the mechanism of action is so far unknown. In the present study, we analyzed the differential expression profiles of miRNA in colostrum and mature milk exosomes using high-throughput sequencing, based on the demonstration that colostrum exosomes inhibit the lipopolysaccharide (LPS)-induced intestinal epithelial NF-κB inflammatory pathway better than mature milk exosomes. The bta-miR-30a-5p, which is specifically highly expressed in colostrum, was screened, and its predicted target gene TRAM was found to be closely related to the NF-κB signaling pathway by functional enrichment analysis. Further, we used gene overexpression and silencing techniques and found that the bta-miR-30a-5p transfection treatment was confirmed to inhibit LPS-induced NF-κB signaling pathway activation and downstream pro-inflammatory factor expression, while the expression of its potential target gene, TRAM, was also suppressed. It is hypothesized that the high expression of bta-miR-30a-5p in colostrum, which targets TRAM to inhibit the downstream NF-κB inflammatory pathway, may be one of the molecular mechanisms responsible for its superior effect on resisting inflammatory attack compared to mature milk.

TRAM deletion attenuates monocyte exhaustion and alleviates sepsis severity

Monocyte exhaustion characterized by immune-suppressive features can develop during sepsis and contribute to adverse patient outcomes. However, molecular mechanisms responsible for the establishment of immune-suppressive monocytes with reduced expression of immune-enhancing mediators such as CD86 during sepsis are not well understood. In this study, we identified that the TLR4 intracellular adaptor TRAM plays a key role in mediating the sustained reduction of CD86 expression on exhausted monocytes and generating an immune-suppressive monocyte state. TRAM contributes to the prolonged suppression of CD86 through inducing TAX1BP1 as well as SARM1, collectively inhibiting Akt and NFκB. TRAM deficient mice are protected from cecal slurry-induced experimental sepsis and retain immune-competent monocytes with CD86 expression. Our data reveal a key molecular circuitry responsible for monocyte exhaustion and provide a viable target for rejuvenating functional monocytes and treating sepsis.

Resolving neutrophils due to TRAM deletion renders protection against experimental sepsis

OBJECTIVE

Proper inflammation resolution is crucial to prevent runaway inflammation during sepsis and reduce sepsis-related mortality/morbidity. Previous studies suggest that deleting TRAM, a key TLR4 signaling adaptor, can reprogram the first inflammatory responder cell-neutrophil from an inflammatory state to a resolving state. In this study, we aim to examine the therapeutic potential of TRAM-deficient neutrophils in vivo with recipient mice undergoing experimental sepsis.

MATERIAL AND METHODS

Wild-type or Tram-/- mice were intraperitoneally injected with cecal slurry to induce either severe or mild sepsis. Phenotypic examinations of sepsis and neutrophil characteristics were examined in vivo and ex vivo. The propagations of resolution from donor neutrophils to recipient cells such as monocytes, T cells, and endothelial cells were examined through co-culture assays in vitro. The efficacies of Tram-/- neutrophils in reducing inflammation were studied by transfusing either wild-type or Tram-/- neutrophils into septic recipient mice.

RESULTS

Tram-/- septic mice had improved survival and attenuated injuries within the lung and kidney tissues as compared to wild-type septic mice. Wild-type septic mice transfused with Tram-/- resolving neutrophils exhibited reduced multi-organ damages and improved cellular homeostasis. In vitro co-culture studies revealed that donor Tram-/- neutrophils can effectively propagate cellular homeostasis to co-cultured neighboring monocytes, neutrophils, T cells as well as endothelial cells.

CONCLUSIONS

Neutrophils with TRAM deletion render effective reprogramming into a resolving state beneficial for ameliorating experimental sepsis, with therapeutic potential in propagating cellular and tissue homeostasis as well as treating sepsis.

Analysis of online materials regarding DIEP and TRAM flap autologous breast reconstruction

Online resources have become a mainstay for health information, and it is vital that such resources maintain accessible literacy levels to empower informed decision making. Previous studies have shown that the online resources regarding post-mastectomy breast reconstruction are of low readability; however, none have evaluated specific online resources regarding the most common procedures within autologous breast reconstruction, limiting analysis to the results of generic searches. This study sought to discover the readability of online, patient-directed resources regarding the Deep Inferior Epigastric Perforator (DIEP) and Transverse Rectus Abdominis Muscle (TRAM) flaps, the most utilized autologous flaps in breast reconstruction, using health literacy analysis. We hypothesized that the online materials regarding DIEP and TRAM flaps would yield literacy scores above the 6th-grade reading level, as recommended by the American Medical Association, despite previous literature and readability recommendations. Google searches for "DIEP breast reconstruction" and "TRAM breast reconstruction" were conducted. All patient-directed, non-sponsored websites found within the first three pages of the search underwent analysis using a variety of readability formulae. Both DIEP and TRAM resources were well above the 6th-grade reading level according to every metric used, and there was no significant difference in the reading level between the two procedures. Based on these results, significant work was needed to simplify the online resources to be more understandable for patients; these authors propose one method for such. In addition, the low readability of online resources suggests added emphasis on the need for surgeons to ensure that patients understand the medical information discussed during the presurgical consultations.

An AP-3-dependent pathway directs phagosome fusion with Rab8 and Rab11 vesicles involved in TLR2 signaling

Intracellular compartmentalization of ligands, receptors and signaling molecules has been recognized as an important regulator of inflammation. The toll-like receptor (TLR) 2 pathway utilizes the trafficking molecule adaptor protein 3 (AP-3) to activate interleukin (IL)-6 signaling from within phagosomal compartments. To better understand the vesicular pathways that may contribute to intracellular signaling and cooperate with AP-3, we performed a vesicular siRNA screen. We identified Rab8 and Rab11 GTPases as important in IL-6 induction upon stimulation with the TLR2 ligand Pam3 CSK4 or the pathogen, Borrelia burgdorferi (Bb), the causative agent of Lyme disease. These Rabs were recruited to late and lysosomal stage phagosomes and co-transported with TLR2 signaling adaptors and effectors, such as MyD88, TRAM and TAK1, in an AP-3-dependent manner. Our data support a model where AP-3 mediates the recruitment of recycling and secretory vesicles and the assembly of signaling complexes at the phagosome.

A genome-wide search of Toll/Interleukin-1 receptor (TIR) domain-containing adapter molecule (TICAM) and their evolutionary divergence from other TIR domain containing proteins

Toll/Interleukin-1 receptor (TIR) domains are cytoplasmic domain that mediates receptor signalling. These domains are present in proteins like Toll-like receptors (TLR), its signaling adaptors and Interleukins, that form a major part of the immune system. These TIR domain containing signaling adaptors binds to the TLRs and interacts with their TIR domains for downstream signaling. We have examined the evolutionary divergence across the tree of life of two of these TIR domain containing adaptor molecules (TICAM) i.e., TIR domain-containing adapter-inducing interferon-β (TRIF/TICAM1) and TIR domain containing adaptor molecule2 (TRAM/TICAM2), by using computational approaches. We studied their orthologs, domain architecture, conserved motifs, and amino acid variations. Our study also adds a timeframe to infer the duplication of TICAM protein from Leptocardii and later divergence into TICAM1/TRIF and TICAM2/TRAM. More evidence of TRIF proteins was seen, but the absence of conserved co-existing domains such as TRIF-NTD, TIR, and RHIM domains in distant relatives hints on diversification and adaptation to different biological functions. TRAM was lost in Actinopteri and has conserved domain architecture of TIR across species except in Aves. An additional isoform of TRAM, TAG (TRAM adaptor with the GOLD domain), could be identified in species in the Mesozoic era. Finally, the Hypothesis based Likelihood ratio test was applied to look for selection pressure amongst orthologues of TRIF and TRAM to search for positively selected sites. These residues were mostly seen in the non-structural region of the proteins. Overall, this study unravels evolutionary information on the adaptors TRAM and TRIF and how well they had duplicated to perform diverse functions by changes in their domain architecture across lineages.

Is Pregnancy Following a TRAM or DIEP Flap Safe? A Critical Systematic Review and Meta-analysis

BACKGROUND

Previous data were not conclusive on the safety of gestation in patients whose abdominal flaps were earlier harvested. We performed a meta-analysis to evaluate the abdominal wall complications and birth mode of pregnancy in post-TRAM or post-DIEP harvested individuals.

METHODS

A literature search was performed using the PubMed, Embase, Scopus, and Google scholar database. Heterogeneity was statistically analyzed, and random effect models were applied. Publication bias was assessed by funnel plot.

RESULTS

We included 25 papers that captured 56 patients giving birth to 69 healthy babies after elevation of abdominally based flaps, with a pooled abdominal complication rate of 0.00-0.09. The complication incidence in TRAM group was 0.01 (95% CI = [0.00-0.14%]) while 0.00 in the DIEP group (95% CI = [0.00-0.26%]). Discrepancies in incidence following unilaterally or bilaterally based TRAM flaps, following free or pedicled TRAM flaps, following primary sutured or mesh strengthened fascia, following MS free TRAM or conventional free TRAM could not be calculated as statistically significant. TRAM group and DIEP group patients had identical birth modes.

CONCLUSIONS

The present meta-analysis did not detect evidence that abdominal walls with the prior harvest of abdominal flaps could affect the process of pregnancy or contraindicate vaginal delivery. No abdominal hernia or bulge occurred with post-DIEP pregnancies. However, such conclusions need to be substantiated by larger sample studies.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .

Heterologous Expression and Assembly of Human TLR Signaling Components in Saccharomyces cerevisiae

Toll-like receptor (TLR) signaling is key to detect pathogens and initiating inflammation. Ligand recognition triggers the assembly of supramolecular organizing centers (SMOCs) consisting of large complexes composed of multiple subunits. Building such signaling hubs relies on Toll Interleukin-1 Receptor (TIR) and Death Domain (DD) protein-protein interaction domains. We have expressed TIR domain-containing components of the human myddosome (TIRAP and MyD88) and triffosome (TRAM and TRIF) SMOCs in Saccharomyces cerevisiae, as a platform for their study. Interactions between the TLR4 TIR domain, TIRAP, and MyD88 were recapitulated in yeast. Human TIRAP decorated the yeast plasma membrane (PM), except for the bud neck, whereas MyD88 was found at cytoplasmic spots, which were consistent with endoplasmic reticulum (ER)-mitochondria junctions, as evidenced by co-localization with Mmm1 and Mdm34, components of the ER and Mitochondria Encounter Structures (ERMES). The formation of MyD88-TIRAP foci at the yeast PM was reinforced by co-expression of a membrane-bound TLR4 TIR domain. Mutations in essential residues of their TIR domains aborted MyD88 recruitment by TIRAP, but their respective subcellular localizations were unaltered. TRAM and TRIF, however, did not co-localize in yeast. TRAM assembled long PM-bound filaments that were disrupted by co-expression of the TLR4 TIR domain. Our results evidence that the yeast model can be exploited to study the interactions and subcellular localization of human SMOC components in vivo.

Development of Exhausted Memory Monocytes and Underlying Mechanisms

Pathogenic inflammation and immuno-suppression are cardinal features of exhausted monocytes increasingly recognized in septic patients and murine models of sepsis. However, underlying mechanisms responsible for the generation of exhausted monocytes have not been addressed. In this report, we examined the generation of exhausted primary murine monocytes through prolonged and repetitive challenges with high dose bacterial endotoxin lipopolysaccharide (LPS). We demonstrated that repetitive LPS challenges skew monocytes into the classically exhausted Ly6Chi population, and deplete the homeostatic non-classical Ly6Clo population, reminiscent of monocyte exhaustion in septic patients. scRNAseq analyses confirmed the expansion of Ly6Chi monocyte cluster, with elevation of pathogenic inflammatory genes previously observed in human septic patients. Furthermore, we identified CD38 as an inflammatory mediator of exhausted monocytes, associated with a drastic depletion of cellular NAD+; elevation of ROS; and compromise of mitochondria respiration, representative of septic monocytes. Mechanistically, we revealed that STAT1 is robustly elevated and sustained in LPS-exhausted monocytes, dependent upon the TRAM adaptor of the TLR4 pathway. TRAM deficient monocytes are largely resistant to LPS-mediated exhaustion, and retain the non-classical homeostatic features. Together, our current study addresses an important yet less-examined area of monocyte exhaustion, by providing phenotypic and mechanistic insights regarding the generation of exhausted monocytes.

The evolution of autologous breast reconstruction

With breast cancer (BC) becoming more treatable, breast reconstruction has become an integral part of BC treatment. Nowadays, implant-based breast reconstruction is more common. However, there is a growing interest in autologous breast reconstruction due to the increasing awareness of implant-related complications. This work provides a comprehensive overview of the evolution of autologous reconstruction techniques of the breast and the nipple-areolar complex (NAC).

Polarization of Low-Grade Inflammatory Monocytes Through TRAM-Mediated Up-Regulation of Keap1 by Super-Low Dose Endotoxin

Subclinical endotoxemia [low levels of bacterial endotoxin (LPS) in the blood stream] has been correlated with chronic inflammatory diseases, with less-understood mechanisms. We have previously shown that chronic exposure to super low doses of LPS polarizes monocytes/macrophages to a pro-inflammatory state characterized by up-regulation of pro-inflammatory regulators such as p62 and simultaneous down-regulation of anti-inflammatory/resolving regulators such as Nrf2. Building upon this observation, here we show that chronic exposure to super-low doses of LPS leads to accumulation of the Nrf2-inhibitory protein Keap1 in murine monocytes. This is accompanied by increases of p62 and MLKL, consistent with a disruption of autolysosome function in polarized monocytes challenged by super-low dose LPS. Monocytes subjected to persistent super-low dose LPS challenge also accumulate higher levels of IKKβ. As a consequence, SLD-LPS challenge leads to an inflammatory monocyte state represented by higher expression of the inflammatory marker Ly6C as well as lower expression of the anti-inflammatory marker CD200R. Further analysis revealed that Keap1 levels are significantly enriched in the Ly6C^hi pro-inflammatory monocyte population. Finally, we show that the TLR4 signaling adaptor TRAM is essential for these effects. Together our study provides novel insight into signaling mechanisms behind low-grade inflammatory monocyte polarization unique to chronic super-low dose LPS exposure.

Assessment of the risk of bulge/hernia formation after abdomen-based microsurgical breast reconstruction with the aid of preoperative computed tomographic angiography-derived morphometric measurements

BACKGROUND

No preoperative risk assessment tool is available to predict postoperative bulge formation after abdomen-based breast reconstruction. The authors evaluated the association between clinical variables and morphometric measurements on preoperative computed tomographic (CT) angiography and postoperative abdominal wall morbidity.

METHODS

The authors evaluated all cases of postoperative bulge/hernia and normal controls in patients who underwent preoperative CT angiography and abdomen-based microsurgical breast reconstruction between July 2009 and January 2018. CT-based abdominal wall profiles, including abdominal wall protrusion, abdominopelvic cavity cross-sectional area (CSA), and abdominopelvic cavity-to-total body CSA ratio, were obtained and analyzed. A novel risk stratification scoring system to stratify the risk of bulge/hernia was developed.

RESULTS

Among 463 patients who underwent abdomen-based breast reconstruction, 23 were diagnosed as having a bulge/hernia. Age (OR 2.912; 95% CI 1.157-7.333), lateral row perforator (OR 5.065; 95% CI 1.834-13.986), and abdominal wall protrusion (OR 3.687; 95% CI 1.494-9.100) were significant risk factors associated with postoperative bulge/hernia in the multivariate analysis. Using the risk stratification scoring system, the incidence rates of postoperative bulge/hernia were 1.7%, 4.8%, and 19.0% for low-, intermediate-, and high-risk patients, respectively (p<0.001).

CONCLUSIONS

Age, lateral row perforator, and abdominal wall protrusion were significantly associated with postoperative bulge/hernia formation after abdomen-based microsurgical breast reconstruction. The authors' risk score based on the three variables may help predict and minimize donor-site morbidity.

[Ectopic expression of archaeal TRAM-encoding genes in rice improves its drought-tolerance]

Drought stress affects the growth and development of rice, resulting in severe loss in yield and quality. Ectopic expression of the bacterial RNA chaperone, cold shock protein (Csp), can improve rice drought tolerance. Archaeal TRAM (TRM2 and MiaB) proteins have similar structure and biochemical functions as bacterial Csp. Moreover, DNA replication, transcription and translation of archaea are more similar to those in eukaryotes. To test if archaeal RNA chaperones could confer plant drought tolerance, we selected two TRAM proteins, Mpsy_3066 and Mpsy_0643, from a cold-adaptive methanogenic archaea Methanolobus psychrophilus R15 to study. We overexpressed the TRAM proteins in rice and performed drought treatment at seedling and adult stage. The results showed that overexpression both TRAM proteins could significantly improve the tolerance of rice to drought stress. We further demonstrated in rice protoplasts that the TRAMs could abolish misfolded RNA secondary structure and improve translation efficiency, which might explain how TRAMs improve drought tolerance transgenic rice. Our work supports that ectopic expression of archaeal TRAMs effectively improve drought tolerance in rice.

[Breast reconstruction by TRAM]

The Transverse Rectus Abominis Musculocutaneous flap or TRAM was first described by Hartrampf in 1982. It consists in raising a abdominal musculocutaneous flap whose perforators vessels come from the superior epigastric vessels. We describe the surgical technique step by step with photos commented on different times.

Donor-site morbidities in 615 patients after breast reconstruction using a free muscle-sparing type I transverse rectus abdominis myocutaneous flap: a single surgeon experience

Transverse rectus abdominis myocutaneous flap is one of the most commonly used reconstruction tools after oncological mastectomy. However, post-operative donor-site morbidities remain an issue to be addressed. In this study, we retrospectively reviewed patients with either immediate or delayed breast reconstruction using a free muscle-sparing type I transverse rectus abdominis myocutaneous flap only, performed by a single surgeon, regarding the donor-site morbidity. From January 2012 to July 2017, the study subjects summed up to 615 patients, in a single institution. Preoperative planning and actual surgical techniques were outlined including the evaluation of the location of the perforators using a three-dimensional abdominal computed tomography angiography scan, minimal fascia sacrifice, beveled dissection and minimization of the tension on the central abdomen during closure. During a 1-year follow-up, a total of 33 patients (5.4%) were complicated with any donor-site morbidity. Those in need of secondary revision on their donor-sites accounted for 23 patients (69.7%). No factor was found statistically significant to increase the risk of donor-site morbidity. Many surgical techniques have been devised for closure of the donor-site in transverse rectus abdominis myocutaneous flap patients. And, several factors have been proposed as increasing the risk of donor-site morbidity. Although all the suggested predictive factors failed to prove its significance on increasing the risk, a set of preoperative planning and surgical techniques employed in our study has proven to be both safe and efficient in lowering the postoperative donor-site morbidities.

Identifying the inhibition of TIR proteins involved in TLR signalling as an anti-inflammatory strategy

Toll/IL1 receptor (TIR) adaptor proteins continue to be an integral part of Toll-like receptors' (TLR) signalling involved in inflammation. Signalling is likely to be initiated by these TIR adaptors when they are recruited to a TIR-TIR interface formed by TLR dimerization. Among these, myeloid differentiation factor-88 (MyD88), MyD88 adapter-like protein (Mal), TIR domain-containing adaptor protein inducing interferon-β (TRIF) and TRIF-related adaptor molecule (TRAM) play pivotal roles at many steps in the signalling events leading to inflammation. The presence of the conserved BB loop residues in the TIR domain of all these important adaptor proteins make them possible targets for inhibition by synthetic compounds. We have designed compounds based on an already known MyD88 TIR dimerization inhibitor, T6167923, which binds well not only to the original target but also to the TIR domains of Mal, TRIF and TRAM. The designed inhibitors are based on modifications of the bromophenyl-sulphonyl-thiophenyl-piperazine-carboxamide series of compounds. We have further suggested modifications in these high-affinity compounds for efficient absorption inside the body. Further, a pharmacophore model highlighting important structural interaction features has been developed. The screened compounds are better in binding to the TIR proteins then the parent compound and hence are good starting points for multi-TIR inhibition.

Conserved TRAM Domain Functions as an Archaeal Cold Shock Protein via RNA Chaperone Activity

Cold shock proteins (Csps) enable organisms to acclimate to and survive in cold environments and the bacterial CspA family exerts the cold protection via its RNA chaperone activity. However, most Archaea do not contain orthologs to the bacterial csp. TRAM, a conserved domain among RNA modification proteins ubiquitously distributed in organisms, occurs as an individual protein in most archaeal phyla and has a structural similarity to Csp proteins, yet its biological functions remain unknown. Through physiological and biochemical studies on four TRAM proteins from a cold adaptive archaeon Methanolobus psychrophilus R15, this work demonstrated that TRAM is an archaeal Csp and exhibits RNA chaperone activity. Three TRAM encoding genes (Mpsy_0643, Mpsy_3043, and Mpsy_3066) exhibited remarkable cold-shock induced transcription and were preferentially translated at lower temperature (18°C), while the fourth (Mpsy_2002) was constitutively expressed. They were all able to complement the cspABGE mutant of Escherichia coli BX04 that does not grow in cold temperatures and showed transcriptional antitermination. TRAM3066 (gene product of Mpsy_3066) and TRAM2002 (gene product of Mpsy_2002) displayed sequence-non-specific RNA but not DNA binding activity, and TRAM3066 assisted RNases in degradation of structured RNA, thus validating the RNA chaperone activity of TRAMs. Given the chaperone activity, TRAM is predicted to function beyond a Csp.

Comparative Perfusion Analysis of Free Muscle-Sparing Versus Pedicle Transverse Rectus Abdominis Myocutaneous (TRAM) Flaps in Vivo in the Peri-Operative and Late Post-Operative Periods

BACKGROUND

Current teaching suggests increased perfusion in free transverse rectus abdominis myocutaneous (TRAM) flaps over pedicled TRAM flaps, broadening indications for its use in high risk patients. This study compared perfusion analysis of free muscle-sparing versus pedicle TRAM flaps in vivo in the peri-operative and late post-operative periods.

METHODS

The SPY-Elite system using indocyanine green dye was used to analyze flap perfusion intra-operatively and at 1 week and 3 months post-operatively. Image analysis was completed by evaluating the perfusion maps from the SPY- Elite system with Image J software calculate maximum, minimum, and average luminescence over the surface area of the flaps. Student's T-test was used for statistical analysis.

RESULTS

Intra-operatively, we found a 73.4% greater perfusion in the free muscle-sparing as compared to the pedicled TRAM. This increase in free muscle-sparing TRAM perfusion was not evident 1 week post-operatively, due to a relative increase in pedicle flap perfusion that coincided with a revision of the pedicled flap due to distal flap necrosis. At 3 months, the free muscle-sparing TRAM flap once again showed superior perfusion with a 15.7% increase over the pedicled flap.

CONCLUSION

We showed superior free muscle-sparing TRAM perfusion in the early peri-operative period which coincided with the time framein which flap loss was most common. Local swelling, pedicle rotation, tunneling, and dominance of the deep inferior epigastric circulation were potential causes of initial decreased pedicled TRAM perfusion. This analysis adds more objective data to the question of indications and relative strengths between free and pedicled TRAM flaps.

Enhancement of vascular endothelial growth factor's angiogenic capacity by the therapeutic modulation of notch signalling improves tram flap survival in rats submitted to nicotine

BACKGROUND

Smoke of cigarettes, and specifically nicotine, has been shown to diminish pedicled transverse rectus abdominis musculocutaneous (TRAM) flap survival. Considering that Notch signalling through its ligand Delta-like 4 (Dll4) functions as anti-angiogenic factor by inhibiting the pro-angiogenic effects of vascular endothelial growth factor (VEGF), it is hypothesised that inhibition of the Notch would promote angiogenesis and increase TRAM flap survival in rats submitted to nicotine.

METHODS

Twenty rats were treated with nicotine for 28 days preoperatively. Thereafter, a pedicled TRAM flap was created in all animals. The Notch inhibitor N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine-t-butyl-ester was administered in animals of the treatment group. Animals in the control group were given the same amount of solvent. Five days after the surgery, viable flap areas were determined. Skin samples were evaluated for VEGF and Dll4 mRNA levels. Immunohistochemical analysis was used for the assessment of endothelial Dll4 expression. Vascular density was determined histologically. Plasma levels of VEGF and Dll4 were measured.

RESULTS

A significant improvement in TRAM flap surviving area was observed in the treatment group (53.50 ± 14.25%) compared with the controls (32.20 ± 9.15%). Immunohistochemical analysis revealed a significant increase in the number of Dll4 stained vessels in animals of the treatment group (9.2 ± 1.6) in comparison with the controls (5.7 ± 1.9). VEGF mRNA levels (0.22 ± 0.08) in the treatment group were significantly lower than those in the control group (0.36 ± 0.09).

CONCLUSION

Notch inhibition significantly improved TRAM flap survival in animals exposed to nicotine by promoting VEGF-induced angiogenesis.

Heme Oxygenase 2 Binds Myristate to Regulate Retrovirus Assembly and TLR4 Signaling

N-myristoylation is the covalent attachment of myristic acid to the N terminus of proteins in eukaryotic cells. The matrix domain (MA) of HIV-1 Gag protein is N-myristoylated and plays an important role in virus budding. In screening for host factors that interact with HIV-1 MA, we found that heme oxygenase (HO-2) specifically binds the myristate moiety of Gag. HO-2 was also found to bind TRAM, an adaptor protein for Toll-like receptor 4 (TLR4), and thereby impact both virus replication and cellular inflammatory responses. A crystal structure revealed that HO-2 binds myristate via a hydrophobic channel adjacent to the heme-binding pocket. Inhibiting HO-2 expression, or blocking myristate binding with a heme analog, led to marked increases in virus production. HO-2 deficiency caused hyperresponsive TRAM-dependent TLR4 signaling and hypersensitivity to the TLR4 ligand lipopolysaccharide. Thus, HO-2 is a cellular myristate-binding protein that negatively regulates both virus replication and host inflammatory responses.

Creating the Perfect Umbilicus: A Systematic Review of Recent Literature

BACKGROUND

The aim of this study was to perform an updated systematic review of the literature over the last 10 years, analyzing and comparing the many published techniques with the hope of providing plastic surgeons with a new standard in creating the perfect umbilicus in the setting of both abdominoplasty and abdominally based free-flap breast reconstruction.

METHODS

An initial search using the PubMed online database with the keyword "umbilicoplasty" was performed. These results were filtered to only include articles published within the last 10 years. The remaining articles were thoroughly reviewed by the authors and only those pertaining to techniques for umbilicoplasty in the setting of abdominoplasty and abdominally based free flap were included.

RESULTS

Of the 10 unique techniques yielded by our search, 9/10 (90 %) initially incised the native umbilicus with a round, oval, or vertical ellipse pattern. Of the 9 techniques that initially perform a round incision, 4 of them (44.4 %) later modify the round umbilicus with either an inferior or superior excision to create either a "U"- or "inverted U"-shaped umbilicus. In terms of the shape of the incision made in the abdominal flap for umbilical reinsertion, the most common were either a round incision or an inverted "V" or "U," both of which accounted for 4/10 (40 %) and 3/10 (30 %), respectively. Almost all of the studies (8/10; 80 %) describe "defatting" or trimming of the subcutaneous adipose tissue around the incision to create a periumbilical concavity following inset of the umbilicus. 4/10 (40 %) of the techniques describe suturing the dermis of the umbilical skin to rectus fascia. Furthermore, 3/10 (30 %) advise that stalk plication is a necessary step to their technique. 7/9 techniques (77.8 %) preferred nondissolvable sutures for skin closure, with nylon being the most common suture material used. Only 2/9 (22.2 %) used dissolvable sutures.

CONCLUSION

Although future studies are necessary, it is our hope that this systematic review better elucidates the techniques and provides some guidance to both aesthetic and reconstructive plastic surgeons in the pursuit of creating the perfect umbilicus following abdominoplasty and TRAM/DIEP breast reconstruction.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Selective salvage of zones 2 and 4 in the pedicled TRAM flap: a focus on reducing fat necrosis and improving aesthetic outcomes

The introduction of microsurgery has decreased the frequency of using the pedicled transverse rectus abdominis musculocutaneous (TRAM) flap, owing to its higher incidence of fat necrosis and limitations in flap insetting (vs. the free TRAM flap). We devised an efficient method of using zones 2 and 4, based on the pedicled flap’s vascular anatomy, to reduce fat necrosis and achieve superior aesthetic outcomes during immediate breast reconstruction using the pedicled TRAM flap. Between April 2011 and February 2015, we performed immediate breast reconstruction using the contralateral unipedicled TRAM flap for 136 breast cancer patients. The conventional method (insetting by removing zone 4 and part of zone 2) was used for 83 patients (Group A), and selective salvage of zones 2 and 4 (our proposed method) was used for 53 patients (Group B). Fat necrosis was observed in 17 patients (20.48 %) and 4 patients (7.55 %) from Groups A and B, respectively (p = 0.033). The average patient satisfaction scores at 6 months (comparing the reconstructed and contralateral breasts) were 7.01 and 8.02 in Groups A and B, respectively (p < 0.001). Liposuction to improve the upper-pole contour was performed at 6 months for 13 patients in Group A, although no patients in Group B required a secondary procedure (p = 0.002). Fat necrosis can be reduced via selective salvage of zones 2 and 4, based on the pedicled TRAM flap’s vascular anatomy. Furthermore, superior aesthetic outcomes can be achieved via flap insetting using the three-dimensional concept. Level of evidence Procedure comparison, Level II.

Flap Failure and Wound Complications in Autologous Breast Reconstruction: A National Perspective

PURPOSE

There are many options for breast reconstruction following a mastectomy, and data on outcomes are greatly needed for both the patient and the care provider. This study aims to identify the prevalence and predictors of adverse outcomes in autologous breast reconstruction in order to better inform patients and surgeons when choosing a surgical technique.

METHODS

This study retrospectively reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and identified each autologous breast reconstruction performed between 2005 and 2012. Of the 6855 autologous breast reconstructions, there were 2085 latissimus dorsi (LD) flap procedures, 2464 pedicled transverse rectus abdominis myocutaneous (TRAM) flap procedures, and 2306 free flap procedures that met the inclusion criteria. The prevalence of complications in each of the three procedures was calculated and compared using χ(2) analysis for binomial categorical variables. Univariate and multivariate logistic regression analyses identified independent risk factors for adverse outcomes in autologous reconstruction as a whole.

RESULTS

The prevalence of general complications was 10.8% in LD flaps, 20.6% in TRAM flaps, and 26.1% in free flaps for autologous breast reconstruction (p < 0.001). The prevalence of wound complications was 4.3% in LD flaps, 8.1% in TRAM flaps, and 6.2% in free flaps for autologous breast reconstruction (p < 0.001). The prevalence of flap failure was 1.1 % in LD flaps, 2.7% in TRAM flaps, and 2.4% in free flaps for autologous breast reconstruction (p < 0.001). Multivariate regression analysis showed that obesity [odds ratio (OR) 1.495, p = 0.024], hypertension (OR 1.633, p = 0.008), recent surgery (OR 3.431, p < 0.001), and prolonged operative times (OR 1.944, p < 0.001) were independently associated with flap failure in autologous breast reconstruction procedures. When controlling for confounding variables, TRAM flaps were twice as likely (OR 2.279, p = 0.001) and free flaps were three times as likely (OR 3.172, p < 0.001) to experience flap failure when compared to LD flaps.

CONCLUSIONS

Latissimus dorsi flaps are associated with the fewest short-term general complications and free flaps are associated with the most short-term general complications in autologous breast reconstruction. Free flaps are the most likely to experience flap failure, though there is no significant difference when compared to pedicled TRAM flaps. Free and TRAM flaps remain as the widely acceptable forms of breast reconstruction in the patient without many risk factors for flap failure or wound complications. The identified risk factors will aid in surgical planning and risk adjustment for both the patient and the care provider. Though many other factors will be taken into consideration with surgical planning of autologous breast reconstruction, the presence of these identified risk factors may encourage the use of a surgical technique associated with fewer adverse outcomes, like the LD flap.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Is Unilateral Implant or Autologous Breast Reconstruction Better in Obtaining Breast Symmetry?

Unilateral breast reconstruction poses a special set of challenges to the reconstructive breast surgeon compared to bilateral reconstructions. No studies to date provide an objective comparison between autologous and implant based reconstructions in matching the contralateral breast. This study compares the quantitative postoperative results between unilateral implant and autologous flap reconstructions in matching the native breast in shape, size, and projection using three-dimensional (3D) imaging. Sixty-four patients who underwent unilateral mastectomy with tissue expander (TE)-implant (n = 34) or autologous microvascular free transverse rectus abdominus myocutaneous (TRAM; n = 18) or deep inferior epigastric artery perforator (DIEP; n = 12) flap (n = 30) reconstruction from 2007 to 2010 were analyzed. Key patient demographics and risk factors were collected. Using 3D scans of patients obtained during pre and postoperative visits including over 1 year follow-ups for both groups, 3D models were constructed and analyzed for total breast volume, anterior-posterior projection from the chest wall, and 3D comparison. No significant differences in mean age, body mass index, or total number of reconstructive surgeries were observed between the two groups (TE-implant: 52.2 ± 10, 23.9 ± 3.7, 3 ± 0.9; autologous: 50.7 ± 9.4, 25.4 ± 3.9, 2.9 ± 1.3; p > 0.05). The total volume difference between the reconstructed and contralateral breasts in the TE-implant group was insignificant: 27.1 ± 22.2 cc, similar to the autologous group: 29.5 ± 24.7 cc, as was the variance of breast volume from the mean. In both groups, the reconstructed breast had a larger volume. A-P projections were similar between the contralateral and the reconstructed breasts in the TE-implant group: 72.5 ± 3.21 mm versus 71.7 ± 3.5 mm (p > 0.05). The autologous reconstructed breast had statistically insignificant but less A-P projection compared to the contralateral breast (81.9 ± 16.1 mm versus 61.5 ± 9.5 mm; p > 0.05). Variance of A-P projection from the mean was additionally insignificant between the contralateral and reconstructed breasts. Both groups produced similar asymmetry scores based on global 3D comparison (TE-implant: 2.24 ± 0.3 mm; autologous: 1.96 ± 0.2 mm; p > 0.05). Lastly, when the autologous group was further subdivided into TRAM and DIEP cohorts, no significant differences in breast volume, A-P projection or symmetry existed. Using 3D imaging, we demonstrate that both TE-implant and autologous reconstruction can achieve symmetrical surgical results with the same number of operations. This study demonstrates that breast symmetry, while an important consideration in the breast reconstruction algorithm, should not be the sole consideration in a patient' decision to proceed with autologous versus TE-implant reconstruction.

An in silico approach towards the identification of novel inhibitors of the TLR-4 signaling pathway

Precise functioning and fine-tuning of Toll-like receptor 4 (TLR4) signaling is a critical requirement for the smooth functioning of the innate immune system, since aberrant TLR4 activation causes excessive production of pro-inflammatory cytokines and interferons. This can result in life threatening conditions such as septic shock and other inflammatory disorders. The TRIF-related adaptor molecule (TRAM) adaptor protein is unique to the TLR4 signaling pathway and abrogation of TRAM-mediated TLR4 signaling is a promising strategy for developing therapeutics aimed at disrupting TRAM interactions with other components of the TLR4 signaling complex. The VIPER motif from the vaccinia virus-producing protein, A46 has been reported to disrupt TRAM-TLR4 interactions. We have exploited this information, in combination with homology modeling and docking approaches, to identify a potential binding site on TRAM lined by the BB loop and αC helix. Virtual screening of commercially available small molecules targeting the binding site enabled to short-list 12 small molecules to abrogate TRAM-mediated TLR4 signaling. Molecular dynamics and molecular mechanics calculations have been performed for the analysis of these receptor-ligand interactions.

CD14, TLR4 and TRAM Show Different Trafficking Dynamics During LPS Stimulation

Toll-like receptor 4 (TLR4) is responsible for the immediate response to Gram-negative bacteria and signals via two main pathways by recruitment of distinct pairs of adaptor proteins. Mal-MyD88 [Mal (MyD88-adaptor-like) - MYD88 (Myeloid differentiation primary response gene (88))] is recruited to the plasma membrane to initiate the signaling cascade leading to production of pro-inflammatory cytokines while TRAM-TRIF [TRAM (TRIF-related adaptor molecule)-TRIF (TIR-domain-containing adapter-inducing interferon-β)] is recruited to early endosomes to initiate the subsequent production of type I interferons. We have investigated the dynamics of TLR4 and TRAM during lipopolysaccharide (LPS) stimulation. We found that LPS induced a CD14-dependent immobile fraction of TLR4 in the plasma membrane. Total internal reflection fluorescence microscopy (TIRF) revealed that LPS stimulation induced clustering of TLR4 into small punctate structures in the plasma membrane containing CD14/LPS and clathrin, both in HEK293 cells and the macrophage model cell line U373-CD14. These results suggest that laterally immobilized TLR4 receptor complexes are being formed and prepared for endocytosis. RAB11A was found to be involved in localizing TRAM to the endocytic recycling compartment (ERC) and to early sorting endosomes. Moreover, CD14/LPS but not TRAM was immobilized on RAB11A-positive endosomes, which indicates that TRAM and CD14/LPS can independently be recruited to endosomes.

Tachycardia in breast reconstructive microsurgery: Affirmation of the IMA tachycardia syndrome

INTRODUCTION

The internal mammary vessels are frequently chosen as recipient vessels for breast free flap reconstruction. We have noticed that when using the internal mammary recipients that these patients have a propensity for tachycardia that was not previously observed. Our aim was to investigate the factors related to perioperative tachycardia in the microsurgical breast reconstruction population and to address whether use of the internal mammary system is a causative factor in tachycardia.

METHODS

A retrospective chart review was conducted to identify patients who underwent abdominal-based microvascular breast reconstruction at the Washington University School of Medicine between 2002 and 2012 to identify the presence of tachycardia. After application of exclusion criteria, 76 microvascular abdominal-based free flap reconstructions were identified. The internal mammary (IM) TRAM group (n = 24) and the thoracodorsal (TD) TRAM group (n = 52) were compared. A binomial logistic regression was performed with the presence of tachycardia as the dependent variable.

RESULTS

There was a higher incidence of tachycardia in the IM TRAM group when compared to the TD TRAM group (p = 0.004). The variables predictive of tachycardia in our logistic regression model were IMA recipient (p = 0.04), need for transfusion (p = 0.03), and presence of fever (p = 0.01).

CONCLUSION

Our study reaffirms that there are several factors that are predictive of tachycardia in the setting of microvascular breast reconstruction. The IMA syndrome should be a recognized cause of tachycardia as using these recipient vessels are shown to be predictive of postoperative tachycardia as shown in our study.

Preoperative anemia impacts early postoperative recovery following autologous breast reconstruction

INTRODUCTION

Preoperative anemia impacts a significant portion of breast reconstruction patients, though this does not appear to affect surgical outcomes. The impact of anemia on postoperative physical and mental health, however, is unknown. This study aimed to prospectively evaluate the role of preoperative anemia in recovery after autologous reconstruction.

METHODS

From 2005 to 2010, we prospectively assessed autologous breast reconstruction patients with satisfaction surveys, strength and functional tests, and the short form 36 (SF36). Data was collected preoperatively and at early (<90d), intermediate (90-365d), and late (>365d) follow-up. We stratified patients by presence or lack of preoperative anemia (hemoglobin<12 g/dL).

RESULTS

Of 399 patients undergoing reconstruction, 179 enrolled in the study. Anemic patients (n = 31, 17%) had higher rates of preoperative chemotherapy (p = 0.02) and lower rates of radiation (p = 0.001). Preoperatively, anemic patients reported worse physical (p < 0.001), mental (p = 0.003) and overall health (p = 0.0003). These scores worsened postoperatively for anemic and nonanemic patients, though anemic patients had lower average scores in all SF36 categories. This was significant only for early follow-up physical health (p = 0.02). Change in SF36 scores and objective physical exam assessments did not differ between the two cohorts.

CONCLUSIONS

Though preoperative anemia may not impact surgical outcomes, it adversely impacts the recovery of breast reconstruction patients. Subjective physical health differences were significant in early follow-up, though this did not translate to differences in mental health or satisfaction. We advocate for preoperative optimization of hemoglobin to enhance the early recovery potential of breast reconstruction patients.

A case report on radiation-induced angiosarcoma of breast post skin-sparing mastectomy and reconstruction with transverse rectus abdominal muscle

Radiation-induced angiosarcomas (RIA) are rare tumours that can affect breast cancer patients following treatment with breast conservative surgery and radiotherapy. Their diagnosis is often delayed because of their benign appearance and the difficulty in differentiation from radiation-induced skin changes. We report here a case of RIA which occurred seven years after radiotherapy to highlight awareness of the disease and the role of careful histological evaluation of these tumours.

Peroxiredoxin V selectively regulates IL-6 production by modulating the Jak2-Stat5 pathway

Mammalian peroxiredoxin V (PrdxV) is a multifunctional protein that protects cells from DNA damage and inhibits stress-induced apoptosis. However, PrdxV is also known to be involved in modulating lipopolysaccharide (LPS)-induced host cell signaling, but its precise role is not fully understood. In this study, we used stably transfected RAW264.7 cells and transiently transfected 293-mTLR4-MD2-CD14 cells expressing wild-type (WT) or mutant (C48S) PrdxV to characterize the function and mechanism of action of PrdxV in LPS-induced immune responses. We found that PrdxV selectively reduces production of interleukin 6 (IL-6) by inhibiting activation of signal transducer and activator of transcription 5 (Stat5) through interaction with Jak2. Notably, this activity of PrdxV was dependent on its catalytic Cys48 residue, but not its peroxidase activity. The binding of to Jak2 effectively inhibited Jak2 phosphorylation, but PrdxV did not act as efficiently as SOCS1 (suppressor of cytokine signaling 1). Our results suggest that PrdxV is a key mediator contributing to the regulation of LPS/TLR4-induced immune responses.

Structures and interface mapping of the TIR domain-containing adaptor molecules involved in interferon signaling

Homotypic and heterotypic interactions between Toll/interleukin-1 receptor (TIR) domains in Toll-like receptors (TLRs) and downstream adaptors are essential to evoke innate immune responses. However, such oligomerization properties present intrinsic difficulties in structural studies of TIR domains. Here, using BB-loop mutations that disrupt homotypic interactions, we determined the structures of the monomeric TIR domain-containing adaptor molecule (TICAM)-1 and TICAM-2 TIR domains. Docking of the monomeric structures, together with yeast two hybrid-based mutagenesis assays, reveals that the homotypic interaction between TICAM-2 TIR is indispensable to present a scaffold for recruiting the monomeric moiety of the TICAM-1 TIR dimer. This result proposes a unique idea that oligomerization of upstream TIR domains is crucial for binding of downstream TIR domains. Furthermore, the bivalent nature of each TIR domain dimer can generate a large signaling complex under the activated TLRs, which would recruit downstream signaling molecules efficiently. This model is consistent with previous reports that BB-loop mutants completely abrogate downstream signaling.

Risk reducing mastectomy, breast reconstruction and patient satisfaction in Norwegian BRCA1/2 mutation carriers

The aim of this study was to evaluate the outcome of risk-reducing mastectomy in BRCA1/2 mutation carriers with and without breast cancer. Uptake, methods of operation and reconstruction, complications, patient satisfaction and histopathological findings were registered at all five departments of genetics in Norway. Data from 267 affected and unaffected BRCA1/2 mutation carriers were analyzed, including a study-specific questionnaire returned by 178 mutation carriers. There was a steady increase in the uptake of risk-reducing mastectomies during the study period. Complications were observed in 106/266 (39.7%) women. Patient satisfaction was high. The majority of women expressed great relief after risk-reducing mastectomy and would have chosen the same option again.

Unique features of chicken Toll-like receptors

Toll-like receptors (TLRs) are a major class of innate immune pattern recognition receptors that have a key role in immune homeostasis and the defense against infections. The research explosion that followed the discovery of TLRs more than a decade ago has boosted fundamental knowledge on the function of the immune system and the resistance against disease, providing a rational for clinical modulation of the immune response. In addition, the conserved nature of the ancient TLR system throughout the animal kingdom has enabled a comparative biology approach to understand the evolution, structural architecture, and function of TLRs. In the present review we focus on TLR biology in the avian species, and, especially, on the unique functional properties of the chicken TLR repertoire.

A high ratio of dietary n-3/n-6 polyunsaturated fatty acids improves obesity-linked inflammation and insulin resistance through suppressing activation of TLR4 in SD rats

Dietary ratios of n-3/n-6 polyunsaturated fatty acids (PUFAs) have been implicated in controlling markers of metabolic disorders, including obesity, insulin resistance (IR), inflammation, and lipid profiles, which are also presumed to be partly related to type 2 diabetes mellitus (T2DM). However, molecular mechanisms of the different PUFAs related to metabolic disorders have not been systematically addressed. The present study aimed to investigate the impact of dietary n-3/n-6 PUFA ratios on obesity and IR and, further, to determine the underlying mechanisms. For 16 weeks, 32 SD male rats, randomly divided into four groups (n = 8 per group), received one of the following diets: normal chow, high saturated fatty acid (SFA), high n-3/n-6 PUFA ratio (1∶1, PUFA¹:¹), or low n-3/n-6 PUFA ratio (1∶4, PUFA¹:⁴). Following the experimental diet period, metabolic parameters related to obesity and IR were measured. Compared to SFA diet-fed rats, PUFA¹:¹ diet-fed rats exhibited decreased body and visceral fat weight, lowered blood lipids, and improved glucose tolerance and insulin sensitivity. Interestingly, these changes were accompanied with decreased expression levels of circulating pro-inflammatory cytokines, including tumor necrosis factor α, interleukin-6, and C-reactive protein. Moreover, the TLR4 protein and mRNA levels were markedly down-regulated by PUFA¹:¹ compared with SFA; however, PUFA¹:⁴ diet-fed rats failed to exhibit these changes. Cumulatively, our data highlight a role for a PUFA¹:¹ diet in the prevention of obesity and related metabolic disorders by suppressing the activation of TLR4, a critical modulator of pro-inflammatory cytokines.

The differential effect of BMI on prosthetic versus autogenous breast reconstruction: a multivariate analysis of 12,986 patients

BACKGROUND

The comparative safety of breast reconstruction in obese patients remains to be clearly defined. This study utilized multi-institutional data to characterize the effect of body mass index (BMI) on breast reconstruction outcomes.

METHODS

Utilizing Current Procedural Terminology (CPT) codes, patients undergoing tissue expander, pedicled transverse rectus abdominis myocutaneous (TRAM) flap, latissimus dorsi flap, and free flap breast reconstruction were identified in the National Surgical Quality Improvement Program (NSQIP) database. Patients were stratified as obese (BMI ≥ 30) and non-obese (BMI < 30). Overall postoperative morbidity, flap complications, non-flap complications, and reoperation rates were compared among the groups.

RESULTS

Of 12,986 patients who underwent breast reconstruction, 3636 (28.0%) were obese. Overall morbidity was significantly elevated in obese patients across all forms of reconstruction (p < 0.05). BMI was correlated with increased surgical complications for tissue expander, pedicled TRAM, and free flap reconstructions (OR = 1.09, OR = 1.05, OR = 1.10, respectively; p < 0.05). Medical complications were higher in obese patients undergoing tissue expander and pedicled TRAM reconstructions (p = 0.001 and p < 0.001), but no significant difference was observed in latissimus and free flap reconstruction patients. Compared with obese tissue expander recipients, obese patients reconstructed using autologous tissue had higher rates of reoperations (12.8% versus 9.1%), overall morbidity (18.0% versus 9.5%), surgical (12.7% versus 8.3%), and medical complications (9.0% versus 2.2%).

CONCLUSIONS

The NSQIP database allows for evaluation and comparison of reconstructive outcomes in the obese population. Increased BMI was associated with higher morbidity in autologous reconstruction than tissue expander reconstruction. Among autologous procedures, latissimus flaps experienced the lowest captured 30 day morbidity.

The structural network of inflammation and cancer: merits and challenges

Inflammation, the first line of defense against pathogens can contribute to all phases of tumorigenesis, including tumor initiation, promotion and metastasis. Within this framework, the Toll-like receptor (TLR) pathway plays a central role in inflammation and cancer. Although extremely useful, the classical representation of this, and other pathways in the cellular network in terms of nodes (proteins) and edges (interactions) is incomplete. Structural pathways can help complete missing parts of such diagrams: they demonstrate in detail how signals coming from different upstream pathways merge and propagate downstream, how parallel pathways compensate each other in drug resistant mutants, how multi-subunit signaling complexes form and in particular why they are needed and how they work, how allosteric events can control these proteins and their pathways, and intricate details of feedback loops and how kick in. They can also explain the mechanisms of some oncogenic SNP mutations. Constructing structural pathways is a challenging task. Here, our goal is to provide an overview of inflammation and cancer from the structural standpoint, focusing on the TLR pathway. We use the powerful PRISM (PRotein Interactions by Structural Matching) tool to reveal important structural information of interactions in and within key orchestrators of the TLR pathway, such as MyD88.

Breast reconstruction practices in north america: current trends and future priorities

The Women's Health and Cancer Rights Act (WHCRA) became federal law on January 1, 1999, mandating health care payer coverage for postmastectomy breast reconstruction. Despite passage of this legislation, breast reconstruction rates in the United States remain low. The Surveillance, Epidemiology and End Results (SEER) database for mastectomy patients in 11 regions across the United States show overall rates for immediate and early delayed reconstruction (performed within 4 months of mastectomy) of 15.4% for 1998 and 18.0% for 2000. Reconstruction rates vary significantly by region as well as by patient age, race, and income. The paper examines potential etiologies for low utilization of breast reconstruction and outlines possible remedies.

Update on Breast Reconstruction Using Free TRAM, DIEP, and SIEA Flaps

Breast reconstruction using autologous tissue is commonly accomplished using the transverse rectus abdominis myocutaneous (TRAM) flap. The establishment of microvascular surgery led to the development of the free TRAM flap because of its increased vascularity and decreased rectus abdominis sacrifice. The muscle-sparing free TRAM, DIEP, and SIEA flap techniques followed in an effort to decrease abdominal donor site morbidity by decreasing injury to the rectus abdominis muscle and fascia. Data have accumulated over the past decade that show that muscle- and fascia-sparing techniques, such as the use of DIEP flaps, result in measurably better postoperative abdominal strength. However, muscle-sparing techniques do not appear to decrease the risk of abdominal bulging or hernia, and there are no significant differences in patient-reported abdominal weakness or functional impairments. The SIEA flap is presented as a reemerging method that can virtually eliminate abdominal donor site morbidity. Sensory nerve coaptation to improve reconstructed breast sensation is also reviewed.