Adjunctive technologies in postoperative free-flap monitoring: a systematic review.

Patent microvascular anastomoses are essential for successful free tissue transfer. Early accurate detection of microvascular compromise is required for flap salvage. Adjunctive monitoring techniques, in addition to clinical examination, are increasingly used to detect flap compromise. This systematic review synthesized and appraised the literature to determine the efficacy of different postoperative monitoring technologies. Rates of flap takeback, salvage, failure, and mean time to detection of microvascular compromise were extracted, synthesized, and reviewed. Twenty-two studies were included, comprising 6370 flaps. One thousand three hundred and ninety-five flaps were monitored with Cook Swartz Doppler (21.83%), 1417 flaps with tissue oximetry (22.24%), 291 with laser Doppler (4.56%), 175 with duplex echography (2.74%), 210 with indocyanine green (ICG) fluorescence (3.30%), 196 with Synovis flow coupler (3.07%), and 81 (1.27%) with light spectroscopy. The overall true positive rate for microvascular compromise in taken back flaps was 70.18%. Cook Swartz Doppler (n = 1391) had a true positive rate of 80.17% and 83.63% salvage rate and was associated with an overall 2.60% rate of flap failure. Tissue oximetry (n = 1417) had a true positive rate of 74.76% and a salvage rate of 88.62%. Laser Doppler, duplex echography, light spectroscopy, and Synovis flow coupler demonstrated true positive rates between 69.4% and 100% with salvage rates between 64% and 100%. Cook Swartz Doppler and tissue oximetry are associated with prompt identification of microvascular compromise and return to theatre. Alternative modalities, including near-infrared spectroscopy, laser Doppler, and duplex echography, show promise. Further well-designed randomised controlled trials (RCTs) appraising head-to-head efficacy are required to comparatively assess adjunctive technologies.

Assessing the validity and sensitivity of microbial processes within a hydrodynamic model.

Eutrophication due to excess anthropogenic nutrients in waterways is a significant issue worldwide. The pressure-stressor-response of a waterway to excessive nutrient loading is reliant on numerous physical and biological factors, including hydrodynamics and microbial processing. While substantial progress has been made towards simulating these mechanisms there are limited multi-disciplinary studies that relate the physical hydrodynamics of a site with the ecological response from linked laboratory and field studies. This paper presents the development of a coupled hydrodynamic and aquatic ecosystem response model, expanded to include an integrated microbial loop, that allows the explicit representation of heterotrophic bacteria growth and dissolved organic nutrient mineralisation. A unique long-term water quality dataset at an estuary in south-eastern Australia was used to validate and assess the model's sensitivity to complex biophysical processes driving the observed water quality variability. Results indicate that explicit time-varying bacterial mineralisation rates provide a substantially improved understanding of the broader aquatic ecosystem response than assigned fixed bulk rate parameter values, which are typically derived from non-local literature. Implementation of a microbial loop at the study site indicated that the model is sensitive to the boundary conditions, in particular catchment loads, with both net transport rates and the net growth rates of heterotrophic bacteria demonstrating different responses. Under average flow conditions, a smaller net transport and reduced nutrient availability has a pronounced effect of lowering net growth rates through the applied limitation factors. During high flow conditions, freshwater inflows increased net transport and nutrient loads, which resulted in higher net growth rates. Further, temporal variability in water temperature had a compounding effect on the model's response sensitivity. This approach has broader application in other riverine systems subject to eutrophication, and in interrogating linkages in hydrodynamic and microbial mediated processes (e.g., productivity). Future studies are recommended to better understand the sensitivity of aquatic ecosystem response models to microbial net growth rate kinetics at different temperatures and from top-down predation (e.g., zooplankton grazing).

Implications of bacterial mineralisation in aquatic ecosystem response models.

Widespread wastewater pollution is a major barrier to the sustainable management of freshwater and coastal marine ecosystems worldwide. Integrated multi-disciplinary studies are necessary to improve waterway management and protect ecosystem integrity. This study used the Generalised Likelihood Uncertainty Estimation (GLUE) methodology to link microbial community ecotoxicology laboratory data to a mechanistic aquatic ecosystem response model. The generic model provided good predictive skill for major water quality constituents, including heterotrophic bacteria dynamics (r2 = 0.91). The model was validated against observed data across a gradient of effluent concentrations from community whole effluent toxicity (WET) laboratory tests. GLUE analysis revealed that a combined likelihood measure increased confidence in the predictive capability of the model. This study highlights the importance of calibrating aquatic ecosystem response models with net growth rates (i.e., sum of the growth minus loss rate parameter terms) of biological functional groups. The final calibrated net growth rate value of heterotrophic bacteria determined using the GLUE analysis was selected to be 0.58, which was significantly greater than the average literature value of -0.15. This finding demonstrated that use of literature parameter values without a good understanding of the represented processes could create misleading outputs and result in unsatisfactory conclusions. Further, fixed bulk mineralisation rate literature values are typically higher than realistically required in aquatic ecosystem response models. This indicates that explicitly including bacterial mineralisation is crucial to represent microbial ecosystem functioning more accurately. Our study suggests that improved data collection and modelling efforts in real-world management applications are needed to better address nutrients released into the natural environment. Future studies should aim to better understand the sensitivity of aquatic ecosystem response models to bacterial mineralisation rates.

Intestinal helminth infection impacts the systemic distribution and function of the naive lymphocyte pool.

Homeostasis is a fundamental principle of biological systems. A paradigm of immune homeostasis is the remarkably constant number of naive T and B lymphocytes in the body that continuously circulate through the secondary lymphoid organs to maximize immune surveillance. Whether the dynamics and distribution of the systemic naive lymphocyte pool is affected following organ-specific infection is not known. Here we show that, following infection of mice with an enteric helminth, naive T and B lymphocytes accumulate in the T helper type 2-reactive mesenteric lymph node while they are concurrently depleted from non-draining peripheral lymph nodes. This systemic redistribution of naive lymphocytes is sustained into the chronic phase of the infection, requires lymphotoxin beta receptor-dependent signals and is associated with a reduced ability of parasitized animals to mount antigen-specific cellular and humoral immune responses to heterologous immunization or infection at peripheral sites. Our data suggest that the function of the homeostatic naive lymphocyte pool can be modulated by its systemic distribution following infection and may provide a novel concept underlying compromised immune responsiveness at peripheral sites in helminth-infected individuals.

Managing parrot bite injuries to the hand: not just another animal bite.

UNLABELLED: Bites and scratches are common injuries, frequently sustained from humans, dogs and cats. Exotic pet-related harm however is an important and increasingly emerging class of injury. Whilst the principles of prompt and thorough medical assessment, antibiotics and potential surgical washout and debridement apply, exotic pet wounds require further consideration. Standard antibiotic prophylaxis with amoxicillin/clavulanic acid (also known as co-amoxiclav) is not sufficient for the pathogens transmitted by parrot bites. We illustrate the importance of adequate consideration of microbiological pathogens with a case report of an open finger fracture resulting from a parrot bite. We intend this to be a valuable resource for healthcare professionals in their effective management of such injuries. LEVEL OF EVIDENCE: V.

One-stage breast reconstruction using the inferior dermal flap, implant, and free nipple graft.

BACKGROUND: An inferior dermal flap with implant is a useful option for women hoping for immediate breast reconstruction. This one-stage procedure uses autologous tissue as an inferolateral local sling, avoiding the costs and potential morbidity of prosthetic mesh and reducing valuable operating time. Patient comorbidity or choice may restrict autologous reconstruction options available. Many patients will still require a second procedure for subsequent nipple reconstruction and further appointments and costs for tattooing. METHOD: A prospective database was kept of a single surgeon's experience with 16 patients (19 breasts) from 2010 to 2012. Reconstruction was performed following a Wise pattern skin incision. An inferior, deepithelialized dermal sling was sutured to the pectoralis major to form a pocket for a silicone implant or tissue expander. A free nipple graft was sited at the time of reconstruction, with biopsies taken from retroareolar tissue. RESULTS: Patient average age was 54 years (range 36-66). Six mastectomies were for ductal carcinoma in situ, 6 for invasive carcinoma, 2 for lobular carcinoma, and 5 of 19 mastectomies were prophylactic. Average operative time was 165 min. There were no immediate complications requiring reoperation. All retroareolar biopsies were benign and no locoregional recurrences have occurred. Two nipples had partial necrosis of the lower pole but healed with conservative treatment. No patients required any subsequent procedures to their reconstructed breast. CONCLUSION: The inferior dermal flap with implant and free nipple graft is an excellent single-stage reconstruction option. This method offers a potentially safe, reliable, and aesthetically acceptable outcome for women with larger, ptotic breasts. LEVEL OF EVIDENCE V: 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 .

Vitamin D in youth with Type 1 diabetes: prevalence of insufficiency and association with insulin resistance in the SEARCH Nutrition Ancillary Study.

AIMS: To determine the prevalence of plasma vitamin D (25-dihydroxyvitamin D) insufficiency in individuals with Type 1 diabetes and to determine the cross-sectional and longitudinal associations of plasma vitamin D with insulin resistance. METHODS: Participants from the SEARCH for Diabetes in Youth Study [n = 1426; mean age 11.2 years (sd 3.9)] had physician-diagnosed Type 1 diabetes [diabetes duration mean 10.2 months (sd 6.5)] with data available at baseline and follow-up (approximately 12 and 24 months after baseline). Insulin resistance was estimated using a validated equation. Cross-sectional and longitudinal multivariate logistic regression models were used to determine the association of plasma vitamin D with insulin resistance, adjusting for potential confounders. RESULTS: Forty-nine per cent of individuals had plasma vitamin D < 50 nmol/l and 26% were insulin resistant. In cross-sectional multivariate analyses, participants who had higher plasma vitamin D (65 nmol/l) had lower odds of prevalent insulin resistance than participants with lower plasma vitamin D (25 nmol/l) (odds ratio 0.70, 95% CI 0.57-0.85). This association was attenuated after additional adjustment for BMI z-score, which could be a confounder or a mediator (odds ratio 0.81, 95% CI 0.64-1.03). In longitudinal multivariate analyses, individuals with higher plasma vitamin D at baseline had lower odds of incident insulin resistance, but this was not significant (odds ratio 0.85, 95% CI 0.63-1.14). CONCLUSIONS: Vitamin D insufficiency is common in individuals with Type 1 diabetes and may increase risk for insulin resistance. Additional prospective studies are needed to determine the association between plasma vitamin D and insulin resistance, and to further examine the role of adiposity on this association.

An age difference of two billion years between a metal-rich and a metal-poor globular cluster.

Globular clusters trace the formation history of the spheroidal components of our Galaxy and other galaxies, which represent the bulk of star formation over the history of the Universe. The clusters exhibit a range of metallicities (abundances of elements heavier than helium), with metal-poor clusters dominating the stellar halo of the Galaxy, and higher-metallicity clusters found within the inner Galaxy, associated with the stellar bulge, or the thick disk. Age differences between these clusters can indicate the sequence in which the components of the Galaxy formed, and in particular which clusters were formed outside the Galaxy and were later engulfed along with their original host galaxies, and which were formed within it. Here we report an absolute age of 9.9 ± 0.7 billion years (at 95 per cent confidence) for the metal-rich globular cluster 47 Tucanae, determined by modelling the properties of the cluster's white-dwarf cooling sequence. This is about two billion years younger than has been inferred for the metal-poor cluster NGC 6397 from the same models, and provides quantitative evidence that metal-rich clusters like 47 Tucanae formed later than metal-poor halo clusters like NGC 6397.

Exploitation of interspecific diversity for monocot crop improvement.

In many cultivated crop species there is limited genetic variation available for the development of new higher yielding varieties adapted to climate change and sustainable farming practises. The distant relatives of crop species provide a vast and largely untapped reservoir of genetic variation for a wide range of agronomically important traits that can be exploited by breeders for crop improvement. In this paper, in what we believe to be the largest introgression programme undertaken in the monocots, we describe the transfer of the entire genome of Festuca pratensis into Lolium perenne in overlapping chromosome segments. The L. perenne/F. pratensis introgressions were identified and characterised via 131 simple sequence repeats and 1612 SNPs anchored to the rice genome. Comparative analyses were undertaken to determine the syntenic relationship between L. perenne/F. pratensis and rice, wheat, barley, sorghum and Brachypodium distachyon. Analyses comparing recombination frequency and gene distribution indicated that a large proportion of the genes within the genome are located in the proximal regions of chromosomes which undergo low/very low frequencies of recombination. Thus, it is proposed that past breeding efforts to produce improved varieties have centred on the subset of genes located in the distal regions of chromosomes where recombination is highest. The use of alien introgression for crop improvement is important for meeting the challenges of global food supply and the monocots such as the forage grasses and cereals, together with recent technological advances in molecular biology, can help meet these challenges.

Buried penis: evaluation of outcomes in children and adults, modification of a unified treatment algorithm, and review of the literature.

Introduction. Buried penis is a difficult condition to manage in children and adults and conveys significant physical and psychological morbidity. Surgery is often declined due to morbid obesity, forcing patients to live in disharmony for years until the desired weight reduction is achieved. No single operative technique fits all. We present our experience and surgical approach resulting in an improved algorithm unifying the treatment of adults and children. Methods. We conducted a retrospective analysis of patients treated for buried penis between 2011 and 2012. All patients underwent penile degloving and basal anchoring. Penile shaft coverage was achieved with skin grafts. Suprapubic lipectomies were performed on adult patients. Results. Nine patients were identified: four children and five obese adults. Average postoperative stay was three days for children and five for adults. Three adults were readmitted with superficial wound problems. One child had minor skin breakdown. All patients were pleased with their outcomes. Conclusion. Buried penis is a complex condition, and treatment should be offered by services able to deal with all aspects of reconstruction. Obesity in itself should not delay surgical intervention. Local and regional awareness is essential to manage expectations in these challenging patients aspiring to both aesthetic and functional outcomes.

Congenital heart disease-associated pulmonary arterial hypertension: preliminary results from a novel registry.

BACKGROUND/AIMS: Pulmonary arterial hypertension (PAH) frequently accompanies childhood congenital heart disease (CHD) and may persist into adult life. The advent of specific PAH therapies for PAH prompted formation of a national Australian and New Zealand registry in 2010 to document the incidence, demographics, presentation and outcomes for these patients. METHODS: This multicentre, prospective, web-based registry enrols patients with CHD-associated PAH being followed in a tertiary centre. The inclusion criteria stipulated patient age ≥16 years, a measured mean pulmonary arterial pressure >25 mmHg at rest or echocardiographical evidence of PAH or a diagnosis of Eisenmenger syndrome, and followed since 1 January 2000. A single observer collected standardised data during a series of site visits. RESULTS: Of the first 50 patients enrolled, 30 (60%) were female. The mean age (standard deviation (SD)) at the time of PAH diagnosis or confirmation in an adult centre was 27.23 (10.07) years, and 32 (64%) patients are currently aged >30 years. Fourteen (28%) patients were in World Health Organization Functional Class II and 36 (72%) in Class III at the time of diagnosis. Forty-seven of 50 (94%) had congenital systemic-pulmonary shunts, and 36 (72%) never underwent intervention. Thirteen (26%) had Down syndrome. Confirmation of PAH by recent cardiac catheterisation was available in 30 (60%) subjects. During follow up, a total of 32 (64%) patients received a PAH-specific therapy. CONCLUSIONS: CHD associated with PAH in adult life has resulted in a new population with unique needs. This registry will allow documentation of clinical course and long-term outcomes for these patients.