Long-term outcomes of latissimus dorsi flap breast reconstructions: A single-centre observational cohort study with up to 12 years of follow up.

INTRODUCTION: The Latissimus Dorsi Myocutaneous Flap (LDMF) is used in post-mastectomy reconstruction. This study has evaluated long-term (up to 12 years) surgical- and patient-reported outcomes from LDMF procedures. METHOD: A retrospective analysis of consecutive LDMF procedures in two UK hospitals, performed between 2006 and 2016. Case notes were reviewed for indications and outcomes. Patients were sent the BREAST-QⓇ survey by post. Outcomes, including surgical adverse events, revision, and implant loss rates, were correlated with patient risk factors. RESULTS: A BREAST-Q was posted to 199/248 LDMF patients in 2018, (excluding 49 patients due to death, reduced cognitive function and incorrect coding) of whom 77 patients responded (38.7%). In 188 cases (representing 208 LDMFs), surgical outcomes were assessable. Median time since LDMF surgery was 7 years (range 2-12). Rates of acute implant loss were 9/139 (6.4%), flap necrosis 7/208 (3.4%), shoulder stiffness 4/208 (1.9%), chronic pain 24/208 (11.5%) and unplanned revision surgery 13/208 (7%). Median satisfaction levels were high with 78% of patients satisfied with treatment outcomes, 65% of patients satisfied with their breasts, 71% of patients satisfied psychosocially and 75% of patients satisfied with their chest. Receipt of radiotherapy was not associated with a higher risk of flap necrosis or capsule formation. CONCLUSION: Long-term follow-up of a large cohort of LDMF reconstruction patients show relatively low levels of adverse events and unplanned revision surgery and high patient satisfaction, which demonstrates how temporally robust the technique is. With the rise in popularity of acellular dermal matrix reconstructions, the LDMF has relatively fallen out of favour but its potential in primary and delayed reconstruction is demonstrated.

In vitro invasion capacity of Salmonella Typhimurium DT9 isolates sourced from humans and layer hen environments.

In Australia, Salmonella Typhimurium definitive type 9 is frequently isolated during foodborne outbreaks of salmonellosis. Multiple-locus variable number tandem repeat analysis (MLVA) trace back investigations frequently identify isolate distribution patterns that may be epidemiologically linked to disease outbreaks. In this study, the in vitro virulence potential of S. Typhimurium DT9 isolates possessing different MLVA patterns (03 15 07 11 550, 03 24 11 10 523, 03 15 08 11 550 and 03 14 08 11 550) isolated from either humans or layer hens was assessed using a human colon carcinoma cell line. Four strains per MLVA from each host for a total of 32 isolates were included in these experiments. Bacteria were grown to stationary phase and added to cells at a multiplicity of infection of 100. Across all isolates, mean percent recovery ranged from 7.1 ± 1.1 to 33.3 ± 7.1%. The layer hen isolate, KC900 (MLVA profile 03 15 08 11 550), exhibited the greatest invasion with a mean percent recovery of 33.3 ± 7.1%. Overall, layer hen isolates of S. Typhimurium DT9 had significantly higher invasion into Caco2 cells than human isolates (p = .0021). RAPD and enterobacterial repetitive intergenic consensus genomic fingerprinting was also performed. Irrespective of source, the SalmonellaDT9 isolates included in this study exhibited similar fingerprint patterns.

Bayesian Source Attribution of Salmonellosis in South Australia.

Salmonellosis is a significant cause of foodborne gastroenteritis in Australia, and rates of illness have increased over recent years. We adopt a Bayesian source attribution model to estimate the contribution of different animal reservoirs to illness due to Salmonella spp. in South Australia between 2000 and 2010, together with 95% credible intervals (CrI). We excluded known travel associated cases and those of rare subtypes (fewer than 20 human cases or fewer than 10 isolates from included sources over the 11-year period), and the remaining 76% of cases were classified as sporadic or outbreak associated. Source-related parameters were included to allow for different handling and consumption practices. We attributed 35% (95% CrI: 20-49) of sporadic cases to chicken meat and 37% (95% CrI: 23-53) of sporadic cases to eggs. Of outbreak-related cases, 33% (95% CrI: 20-62) were attributed to chicken meat and 59% (95% CrI: 29-75) to eggs. A comparison of alternative model assumptions indicated that biases due to possible clustering of samples from sources had relatively minor effects on these estimates. Analysis of source-related parameters showed higher risk of illness from contaminated eggs than from contaminated chicken meat, suggesting that consumption and handling practices potentially play a bigger role in illness due to eggs, considering low Salmonella prevalence on eggs. Our results strengthen the evidence that eggs and chicken meat are important vehicles for salmonellosis in South Australia.

Identification, structural and pharmacological characterization of τ-CnVA, a conopeptide that selectively interacts with somatostatin sst3 receptor.

Conopeptides are a diverse array of small linear and reticulated peptides that interact with high potency and selectivity with a large diversity of receptors and ion channels. They are used by cone snails for prey capture or defense. Recent advances in venom gland transcriptomic and venom peptidomic/proteomic technologies combined with bioactivity screening approaches lead to the identification of new toxins with original pharmacological profiles. Here, from transcriptomic/proteomic analyses of the Conus consors cone snail, we identified a new conopeptide called τ-CnVA, which displays the typical cysteine framework V of the T1-conotoxin superfamily. This peptide was chemically synthesized and its three-dimensional structure was solved by NMR analysis and compared to that of TxVA belonging to the same family, revealing very few common structural features apart a common orientation of the intercysteine loop. Because of the lack of a clear biological function associated with the T-conotoxin family, τ-CnVA was screened against more than fifty different ion channels and receptors, highlighting its capacity to interact selectively with the somatostatine sst3 receptor. Pharmacological and functional studies show that τ-CnVA displays a micromolar (Ki of 1.5µM) antagonist property for the sst3 receptor, being currently the only known toxin to interact with this GPCR subfamily.

Translational mini-review series on complement factor H: structural and functional correlations for factor H.

The 155-kDa glycoprotein, complement factor H (CFH), is a regulator of complement activation that is abundant in human plasma. Three-dimensional structures of over half the 20 complement control protein (CCP) modules in CFH have been solved in the context of single-, double- and triple-module segments. Proven binding sites for C3b occupy the N and C termini of this elongated molecule and may be brought together by a bend in CFH mediated by its central CCP modules. The C-terminal CCP 20 is key to the ability of the molecule to adhere to polyanionic markers on self-surfaces where CFH acts to regulate amplification of the alternative pathway of complement. The surface patch on CCP 20 that binds to model glycosaminoglycans has been mapped using nuclear magnetic resonance (NMR), as has a second glycosaminoglycan-binding patch on CCP 7. These patches include many of the residue positions at which sequence variations have been linked to three complement-mediated disorders: dense deposit disease, age-related macular degeneration and atypical haemolytic uraemic syndrome. In one plausible model, CCP 20 anchors CFH to self-surfaces via a C3b/polyanion composite binding site, CCP 7 acts as a 'proof-reader' to help discriminate self- from non-self patterns of sulphation, and CCPs 1-4 disrupt C3/C5 convertase formation and stability.

Replication of dengue virus type 2 in human monocyte-derived macrophages: comparisons of isolates and recombinant viruses with substitutions at amino acid 390 in the envelope glycoprotein.

The severity of dengue virus infection ranges from mild fever to dengue hemorrhagic fever and shock syndrome. The association of disease severity with virus replication in monocyte-derived macrophages (MDMs) was examined for dengue virus type 2 (DEN-2) isolates from Asia or America. Additionally, we constructed DEN-2 recombinant viruses with substitutions at residue 390 in the envelope glycoprotein (E390) because this residue is linked with the region of virus origin. Comparisons of virus yields of 3 isolates failed to show a correlation with clinical disease. However, the American strain did not replicate as well as the 2 Asian strains. For the recombinant viruses, substitution of Asn (Asian) at E390 with Asp (American) resulted in decreased ability to replicate in MDMs. These results are consistent with the proposal that the lack of association of native American DEN-2 strains with severe disease is linked to reduced ability to replicate in MDMs, and that Asp at E390 may contribute to this reduction.

Specific inhibition of human immunodeficiency virus type 1 (HIV-1) integration in cell culture: putative inhibitors of HIV-1 integrase.

To study the effect of potential human immunodeficiency virus type 1 (HIV-1) integrase inhibitors during virus replication in cell culture, we used a modified nested Alu-PCR assay to quantify integrated HIV DNA in combination with the quantitative analysis of extrachromosomal HIV DNA. The two diketo acid integrase inhibitors (L-708,906 and L-731,988) blocked the accumulation of integrated HIV-1 DNA in T cells following infection but did not alter levels of newly synthesized extrachromosomal HIV DNA. In contrast, we demonstrated that L17 (a member of the bisaroyl hydrazine family of integrase inhibitors) and AR177 (an oligonucleotide inhibitor) blocked the HIV replication cycle at, or prior to, reverse transcription, although both drugs inhibited integrase activity in cell-free assays. Quercetin dihydrate (a flavone) was shown to not have any antiviral activity in our system despite reported anti-integration properties in cell-free assays. This refined Alu-PCR assay for HIV provirus is a useful tool for screening anti-integration compounds identified in biochemical assays for their ability to inhibit the accumulation of integrated HIV DNA in cell culture, and it may be useful for studying the effects of these inhibitors in clinical trials.

Rapid and efficient cell-to-cell transmission of human immunodeficiency virus infection from monocyte-derived macrophages to peripheral blood lymphocytes.

Macrophages are considered of central importance in cell-to-cell transmission of human immunodeficiency virus (HIV) infection in vivo. In this report, we describe a novel cell-to-cell transmission model using HIV-infected monocyte-derived macrophages (MDMs) as donor cells and peripheral blood lymphocytes (PBLs) as recipients. Virus was transmitted during a 2-h coincubation period from intracellular or tightly cell-associated viral stores in adherent infected MDMs to nonadherent CD3(+) PBLs. Transmission required cell contact, but syncytia formation was not observed. HIV cell-to-cell transmission occurred in both allogeneic and autologous systems, and replication was higher in phytohemagglutinin (PHA)-stimulated than unstimulated recipient PBLs. In contrast, transmission of infection by cell-free virus was barely detectable without PHA stimulation of recipients, suggesting the cell-cell interaction may have provided stimuli to recipient cells in the cell-to-cell system. Viral DNA levels increased 5-24 h postmixing, and this increase was inhibited by pretreatment of cells with the reverse transcription inhibitor azidothymidine, indicating de novo reverse transcription was involved. Cell-to-cell transmission was more efficient than infection with cell-free virus released from donor MDMs, or 0.1 TCID(50)/cell cell-free viral challenge. This model provides a system to further investigate the mechanisms and characteristics of HIV cell-to-cell transmission between relevant primary cells that may be analogous to this important mode of virus spread in vivo.