Radiomic models for lymph node metastasis prediction in cervical cancer: can we think beyond sentinel lymph node?

Liu and colleagues performed a retrospective study to validate a computed tomography (CT) scan-based radiomic model to detect lymph node metastasis in cervical cancer. The proposed model incorporating the arterial and venous phase CT-scan features represented a non-invasive method exhibiting high sensitivity in the prediction of lymph node metastasis. It is well established that lymph node metastasis is one of the most significant prognostic factors in cervical cancer. For this reason, management of cervical cancer is strictly related to lymph node status, with international guidelines recommending definitive chemo-radiation in case of metastatic lymph node. More and more evidence supports the use of sentinel lymph node in early-stage cervical cancer but its frozen section analysis may result in false negative results; in locally-advanced stages staging para-aortic lymphadenectomy is proposed by many Authors to tailor chemoradiotherapy treatment, with potential intra-and post-operative related complications. The use of a validated radiomic model able to predict lymph node metastases in radiologically normal lymph nodes may represent an essential tool to possibly spare lympadenectomy related morbidity.     

Is Zooplankton Body Size an Indicator of Water Quality in (Sub)tropical Reservoirs in China?

Ecosystems - Large zooplankton can efficiently graze on algae and thereby improve water quality. However, zooplankton body size is considered to decrease with decreasing latitude because of the...     

Is sodium current present in human sinoatrial node cells?

Pacemaker activity of the sinoatrial node has been studied extensively in various animal species, but is virtually unexplored in man. As such, it is unknown whether the fast sodium current (I_Na) plays a role in the pacemaker activity of the human sinoatrial node. Recently, we had the unique opportunity to perform patch-clamp experiments on single pacemaker cells isolated from a human sinoatrial node. In 2 out of the 3 cells measured, we observed large inward currents with characteristics of I_Na. Although we were unable to analyze the current in detail, our findings provide strong evidence that I_Na is present in human sinoatrial node pacemaker cells, and that this I_Na is functionally available at potentials negative to -60 mV.     

Laparoscopic radical prostatectomy in obese patients: feasible or foolhardy?

More than 70% of men who are candidates for radical prostatectomy can be classified as either overweight or obese by body mass index. The role for laparoscopic radical prostatectomy (LRP) in treating these patients remains to be defined. A wealth of experience from bariatric surgery confirms that laparoscopic procedures can be performed successfully, even in the setting of morbid obesity, despite well-defined derangements in respiratory dynamics. Using the technical modifications outlined here, LRP can be performed safely and effectively in obese patients. Obesity raises the degree of difficulty for LRP, however, resulting in longer operative times and possibly a higher rate of open conversion. For this reason, surgeons early in their LRP experience are advised to avoid obese patients until they have become facile in the performance of LRP in normal-weight individuals.     

Is bioaugmentation a feasible strategy for pollutant removal and site remediation?

Microorganisms can degrade numerous organic pollutants owing to their metabolic machinery and to their capacity to adapt to inhospitable environments. Thus, microorganisms are major players in site remediation. However, their efficiency depends on many factors, including the chemical nature and the concentration of pollutants, their availability to microorganisms, and the physicochemical characteristics of the environment. The capacity of a microbial population to degrade pollutants within an environmental matrix (e.g. soil, sediment, sludge or wastewater) can be enhanced either by stimulation of the indigenous microorganisms by addition of nutrients or electron acceptors (biostimulation) or by the introduction of specific microorganisms to the local population (bioaugmentation). Although it has been practiced in agriculture and in wastewater treatment for years, bioaugmentation is still experimental. Many factors (e.g. predation, competition or sorption) conspire against it. However, several strategies are currently being explored to make bioaugmentation a successful technology in sites that lack significant populations of biodegrading microorganisms. Under optimal local conditions, the rate of pollutant degradation might increase upon addition of an inoculant to remediate a chemical spill; however, the most successful cases of bioaugmentation occur in confined systems, such as bioreactors in which the conditions can be controlled to favour survival and prolonged activity of the exogenous microbial population.     

Is WIC effective in improving pregnancy-related outcomes? An empirical reassessment

This study provides new evidence on how prenatal WIC participation influences pregnancy-related outcomes, using a large dataset of Medicaid mothers with two or more singleton births. Our analysis suggests there is negative selection by maternal unobserved factors even with a relatively homogenous sample and a rich set of observed characteristics. The conservative estimates from multiple regression which doesn’t address maternal unobserved heterogeneity already demonstrate beneficial effects on a range of outcomes. The concern of mis-specification or extrapolation in the linear model is also ruled out. Controlling for the mother fixed effects, we find more statistically significant estimates which are usually larger in size. The within-mother estimates are robust in a series of sensitivity checks especially multiple inference adjustments. Overall, we find WIC does work to improve infant health and maternal health behaviors as well as reduce usage of costly maternity care.     

Is Body Mass Index a Measure of Adiposity in Elderly Women?

Objective: To evaluate the accuracy of body mass index (BMI) as a predictor of body fat in elderly women. Research Methods and Procedures: A total of 1423 women aged 67 ± 5 (mean ± SD, range: 60 to 88) years were consecutively enrolled into the study. Fat mass (FM) was measured using DXA. Results: BMI explained 72.9% of FM variance (p < 0.0001), with a root mean square error of estimate (RMSE) of 3.5 kg. After standardization of RMSE on the dependent variable as RMSE%, the prediction error equaled 15%. BMI explained 54.8% of FM% variance (p < 0.0001), with an RMSE of 4.1%, corresponding to an RMSE% of 11%. Discussion: The relatively high RMSE% of the FM and FM%‐BMI associations caution against the use of BMI as an adiposity index in individual elderly women. However, an error corresponding to 11% of FM% may be accepted for population studies of body fat in elderly women.     

Is the dichogamy ofSalvia verbenaca (Lamiaceae) an effective barrier to self-fertilization?

Though dichogamy is generally interpreted as a means of preventing self-fertilization, the efficiency of this mechanism has been questioned. Little attention has been paid to functional aspects of male/female timing, such as variation over time in pollen germinability and in stigma receptivity. In the present study these aspects of male/female timing were investigated in the protandrous speciesSalvia verbenaca. To evaluate the effects of selfing, fruit set, total seed weight produced and seed/ovule ratio were also determined, (a) following artificial crossing, (b) following selfing (i.e. bagging) and (c) under natural conditions. Both pollen germinability and stigma receptivity peaked on the last day (day 3) of the flower's life, which presumably favours selfing. Neither fruit set nor seed/ovule ratio were significantly affected by pollination regime, but the total seed weight produced by artificially crossed plants was significantly higher than that produced by bagged or untreated plants. Neither fruit set, seed/ovule ratio nor total seed weight differed significantly between the two years of study. Thus, if aS. verbenaca flower receives outcrossing pollen it will produce a greater weight of seeds (with consequent advantages in terms of female reproductive success). However, the peaking of both pollen germinability and stigma receptivity on day 3 of the flower's life means that selfing is likely to occur if outcrossing pollen has not been received over the early part of the flower's life.     

Is screening and intervention for microalbuminuria worthwhile in patients with insulin dependent diabetes?

OBJECTIVE--To analyse the cost-benefit of screening for and antihypertensive treatment of early renal disease indicated by microalbuminuria in patients with insulin dependent diabetes mellitus. DESIGN--Previously published data were used to estimate transition probabilities for each step from normoalbuminuria until death. The effect of intervention on urinary albumin excretion rate by antihypertensive treatment was arbitrarily set at three different levels. All direct costs (screening, antihypertensive treatment, treatment of end stage renal failure) were included in the cost-benefit analysis by using real discount rates of 2.5% and 6%. SETTING--Computer simulation. SUBJECTS--Simulated cohort of 8000 patients. MAIN OUTCOME MEASURES--Mortality, incidence of diabetic nephropathy, incidence of end stage renal failure, and costs versus savings. RESULTS--Assuming treatment effects of 33% and 67% median life expectancy increased by four to 14 years, respectively, and the need for dialysis or transplantation decreased by 21% to 63%. Costs and savings would balance if the annual rate of increase of albuminuria was decreased from 20% to 18% a year. CONCLUSIONS--Screening and intervention programmes are likely to have life saving effects and lead to considerable economic savings.     

Interspecific comparisons of lymph volume and lymphatic fluxes: do lymph reserves and lymph mobilization capacities vary in anurans from different environments?

The femoral lymph sac volumes and lymph mobilization capacity were compared in three anuran species that span a range of environments, dehydration tolerance, ability to maintain blood volume with dehydration, and degrees of development of skeletal muscles putatively involved in moving lymph vertically to the posterior lymph hearts. The femoral lymph sac volume determined by Evans blue injection and dilution in the femoral lymph sac varied interspecifically. The semiaquatic species, Lithobates catesbeianus, had the greatest apparent lymph volume expressed either as 18.7 mL kg body mass?1 or 94 mL kg thigh mass?1, compared with both the terrestrial and aquatic species, Rhinella marina (7.3 mL kg body mass?1 and 57 mL kg thigh mass?1) and Xenopus laevis (6.5 mL kg body mass?1 and 40 mL kg thigh mass?1, respectively. Injections of Evans blue into the subvertebral lymph sac, which communicates with both pairs of lymph hearts, yielded the highest rates of lymph return to the circulation in all three species. The most terrestrial species had a greater rate of lymphatic return from the subvertebral lymph sac, compared with the other two species. The rate of lymph flux from the femoral sac varied interspecifically and was correlated with the number and development of skeletal muscles involved in lymph movement. The results indicated that the three species differ in both the volume of lymph present and the capacity to return lymph. Lymph flux was correlated with habitat and the ability to maintain blood volume when challenged by dehydration or hemorrhage, whereas femoral lymph volume was not correlated with these factors.     

Is fatter fitter? Body storage and reproduction in ten populations of the freshwater amphipod Gammarus minus

Relationships between body storage (estimated as fat content and residuals of body mass regressed against body length) and offspring investment [brood mass, brood size (number of embryos per brood) and embryo mass] were examined within and among populations of the amphipod Gammarus minus in ten cold springs in central Pennsylvania, USA. Two major hypotheses and six corollary hypotheses were tested. Total reproductive investment (brood mass and brood size) was usually strongly positively correlated with maternal body length and body storage both within and among populations. These positive associations between reproductive and somatic investments are expected if individual variation in resource acquisition exceeds that of resource allocation. That is, individuals or populations that are able to acquire more resources should also be able to allocate more resources to both reproduction and somatic reserves than those acquiring fewer resources. This hypothesis is consistent with evidence showing that individual differences in body storage in G. minus and other amphipods are related to differences in resource acquisition. Positive associations between reproductive and somatic investments do not mean that energy costs of reproduction do not exist in G. minus. Evidence for reproductive energy costs included the lower body-fat contents of brooding versus nonbrooding females and the relatively low body mass per length of females who had just deposited eggs in their brood pouch. Unlike brood mass and brood size, individual embryo mass was usually unrelated to maternal body length and body storage. This pattern is largely consistent with optimal offspring investment theory, which predicts that offspring size should be insensitive to variation in parental resource status. However, in contrast to theory, embryo mass increased in winter when brooding females were significantly ”fatter”, presumably due to the availability of autumn-shed leaf food. This seasonal change in offspring size may be a maternally mediated effect of increased resource availability, though other explanations are possible. Overall, this study suggests that ”fatter” female amphipods are fitter than ”thinner” ones, though both the costs and benefits of increased body storage and brood size require investigation to substantiate this claim. This study also suggests that effects of individual variation in resource acquisition on life-history patterns deserve more theoretical and empirical attention by ecologists than they have received. It should be recognized that positive and/or nonsignificant correlations between life-history traits are just as interesting and important as are the negative correlations predicted by many theoretical models. Received: 20 January 1999 / Accepted: 26 September 1999     

Is mitral valve repair safe procedure in elderly patients?

The aim of this randomized, prospective, study was to evaluate postoperative hospital mortality and morbidity after mitral valve repair by comparing two surgical techniques for resolving mitral valve insufficiency in elderly patients. In comparison were: mitral valve repair vs. mitral valve replacement in patients older than 70 years. In period from January 1st 2006 until August 30th 2009. Eighty patients with mitral valve disease, isolated or associated with other comorbidities, were scheduled for mitral valve repair or mitral valve replacement in our institution. Patients were randomized in two groups, one scheduled for mitral valve repair and another one for mitral valve replacement using the envelope method with random numbers. Results show no difference in hospital mortality and morbidity postoperatively in both groups. In group undergoing valve replacement we had one significant complication of ventricle rupture in emphatically calcified posterior part of mitral valve annulus. In conclusion we found no distinction in postoperative hospital mortality and morbidity after using one of two surgical techniques.