Phosphate Control in Peritoneal Dialysis Patients: Issues, Solutions, and Open Questions.

Hyperphosphatemia is a common complication in advanced chronic kidney disease and contributes to cardiovascular morbidity and mortality. The present narrative review focuses on the management of phosphatemia in uremic patients receiving peritoneal dialysis. These patients frequently develop hyperphosphatemia since phosphate anion behaves as a middle-size molecule despite its low molecular weight. Accordingly, patient transporter characteristics and peritoneal dialysis modalities and prescriptions remarkably influence serum phosphate control. Given that phosphate peritoneal removal is often insufficient, especially in lower transporters, patients are often prescribed phosphate binders whose use in peritoneal dialysis is primarily based on clinical trials conducted in hemodialysis because very few studies have been performed solely in peritoneal dialysis populations. A crucial role in phosphate control among peritoneal dialysis patients is played by diet, which must help in reducing phosphorous intake while preventing malnutrition. Moreover, residual renal function, which is preserved in most peritoneal dialysis patients, significantly contributes to maintaining phosphate balance. The inadequate serum phosphate control observed in many patients on peritoneal dialysis highlights the need for large and well-designed clinical trials including exclusively peritoneal dialysis patients to evaluate the effects of a multiple therapeutic approach on serum phosphate control and on hard clinical outcomes in this high-risk population.

Immune Checkpoint Inhibitors and the Kidney: A Focus on Diagnosis and Management for Personalised Medicine.

Immunity plays a crucial role in fighting cancer, but tumours can evade the immune system and proliferate and metastasize. Enhancing immune responses is a new challenge in anticancer therapies. In this context, efficacy data are accumulating on immune checkpoint inhibitors and adjuvant therapies for various types of advanced-stage solid tumours. Unfortunately, immune-related adverse events are common. Although infrequent, renal toxicity may occur via several mechanisms and may require temporary or permanent drug suspension, renal biopsy, and/or immunosuppressive treatment. This short review aims to provide a practical approach to the multidisciplinary management of cancer patients with renal toxicity during treatment with immune checkpoint inhibitors.

From a circle to a sphere: the ultrasound imaging of ovarian follicle with 2D and 3D technology.

Ultrasound follicular count (antral follicle count, AFC) is a necessary tool for measuring ovarian reserve, whereby the estimated number of follicles responsive to FSH can predict the number of oocytes retrieved in IVF cycles and may be the basis for individualized ovarian stimulation therapy. Advances in the ultrasound technology have recently lead to the improvement in resolution and quality of the image. Moreover the automatic measurements of follicular diameter by using some specific 3D software seems associated to several advantages when compared to the 2D technique. Examination time is reduced because the ultrasound scan data are stored and can be analyzed in detail at a later time. These data can be reconstructed in any plane, regardless of the original scan plane facilitating the detailed analysis. Another advantage is that this new technique reduces the operator's influence on scan interpretation and objectivity; therefore, interobserver variability is reduced. Using follicular volume obtained with sono AVC as the measure of follicular growth combined with volume-based criteria for the hCG triggering may in the future improve the treatment outcome compared to that achieved with conventional monitoring with follicular diameter. Better knowledge in this area could be helpful to optimize IVF outcome, by refining ovarian stimulation protocols and obtain high quality oocytes.

High prevalence of physical inactivity among patients from the Swiss HIV Cohort Study.

Physical activity (PA) can improve cardiorespiratory status, strength, body composition and quality of life for patients infected with HIV. Evidence from HIV-uninfected populations also shows that PA is associated with a lower risk of mortality, primarily death due to cardiovascular causes. There is, however, a lack of data on how physically active HIV-infected patients are. In this study, we assessed levels of self-reported PA over time in patients enrolled in the Swiss HIV Cohort Study, a large multicentre prospective observational cohort study. We included a total of 10,540 patients who completed at least one report of PA between December 2009 and November 2014 during routine clinical follow-up (scheduled every 6 months). In the first year after December 2009 there was a higher rate of non-response so these data are of a lesser reliability. Over the next four years, the percentage of patients reporting no free-time PA at all declined from 49% to 44%. In contrast, in two "Sport Switzerland" surveys of the general population in 2008 and 2014, the percentage of individuals reporting no sports activities at all was considerably lower and relatively stable over time (27% in 2008; 26% in 2014). In our analysis, the percentage of patients reporting sedentary activity at work increased from 23% to 26% over the four years. Subgroup findings suggest differences between women and men and between patients classified by their age, stage of infection and CD4 cell count. Integrating PA counselling into the routine care of HIV-infected patients and promoting PA among this population has the potential to improve the general state of health and quality of life for HIV-infected patients and reduce their risk of cardiovascular disease.

Contribution of Genetic Background and Clinical Risk Factors to Low-Trauma Fractures in Human Immunodeficiency Virus (HIV)-Positive Persons: The Swiss HIV Cohort Study.

Background. The impact of human genetic background on low-trauma fracture (LTF) risk has not been evaluated in the context of human immunodeficiency virus (HIV) and clinical LTF risk factors. Methods. In the general population, 6 common single-nucleotide polymorphisms (SNPs) associate with LTF through genome-wide association study. Using genome-wide SNP arrays and imputation, we genotyped these SNPs in HIV-positive, white Swiss HIV Cohort Study participants. We included 103 individuals with a first, physician-validated LTF and 206 controls matched on gender, whose duration of observation and whose antiretroviral therapy start dates were similar using incidence density sampling. Analyses of nongenetic LTF risk factors were based on 158 cases and 788 controls. Results. A genetic risk score built from the 6 LTF-associated SNPs did not associate with LTF risk, in both models including and not including parental hip fracture history. The contribution of clinical LTF risk factors was limited in our dataset. Conclusions. Genetic LTF markers with a modest effect size in the general population do not improve fracture prediction in persons with HIV, in whom clinical LTF risk factors are prevalent in both cases and controls.

Identification of thyroid tumor cell vulnerabilities through a siRNA-based functional screening.

The incidence of thyroid carcinoma is rapidly increasing. Although generally associated with good prognosis, a fraction of thyroid tumors are not cured by standard therapy and progress to aggressive forms for which no effective treatments are currently available. In order to identify novel therapeutic targets for thyroid carcinoma, we focused on the discovery of genes essential for sustaining the oncogenic phenotype of thyroid tumor cells, but not required to the same degree for the viability of normal cells (non-oncogene addiction paradigm). We screened a siRNA oligonucleotide library targeting the human druggable genome in thyroid cancer BCPAP cell line in comparison with immortalized normal human thyrocytes (Nthy-ori 3-1). We identified a panel of hit genes whose silencing interferes with the growth of tumor cells, while sparing that of normal ones. Further analysis of three selected hit genes, namely Cyclin D1, MASTL and COPZ1, showed that they represent common vulnerabilities for thyroid tumor cells, as their inhibition reduced the viability of several thyroid tumor cell lines, regardless the histotype or oncogenic lesion. This work identified non-oncogenes essential for sustaining the phenotype of thyroid tumor cells, but not of normal cells, thus suggesting that they might represent promising targets for new therapeutic strategies.

Live birth rates in the different combinations of the Bologna criteria poor ovarian responders: a validation study.

PURPOSE: to compare the baseline characteristics and chance of live birth in the different categories of poor responders identified by the combinations of the Bologna criteria and establish whether these groups comprise a homogenous population. METHODS: database containing clinical and laboratory information on IVF treatment cycles carried out at the Mother-Infant Department of the University Hospital of Modena between year 2007 and 2011 was analysed. This data was collected prospectively and recorded in the registered database of the fertility centre. Eight hundred and thirty women fulfilled the inclusion/ exclusion criteria of the study and 210 women fulfilled the Bologna criteria definition for poor ovarian response (POR). Five categories of poor responders were identified by different combinations of the Bologna criteria. RESULTS: There were no significant differences in female age, AFC, AMH, cycle cancellation rate and number of retrieved oocytes between the five groups. The live birth rate ranged between 5.5 and 7.4 % and was not statistically different in the five different categories of women defined as poor responders according to the Bologna criteria. CONCLUSION: The study demonstrates that the different groups of poor responders based on the Bologna criteria have similar IVF outcomes. This information validates the Bologna criteria definition as women having a uniform poor prognosis and also demonstrates that the Bologna criteria poor responders in the various subgroups represent a homogenous population with similar pre-clinical and clinical outcomes.

Fetal thymus volume estimation by virtual organ computer-aided analysis in normal pregnancies.

OBJECTIVES: The thymus has a pyramidal shape, which is best shown in coronal planes. The aim of this study was to evaluate the potential of virtual organ computer-aided analysis to estimate fetal thymus volume in normal pregnancies. METHODS: Three-dimensional volume data sets from the axial upper mediastinal section were acquired from 37 normal pregnancies between 12 and 35 weeks' gestation. Thymus volume was calculated by virtual organ computer-aided analysis by 2 separate examiners. In 12 cases, volumes were also acquired with 4-dimensional sonography and spatiotemporal image correlation software to assess the variability in thymus size between the systolic and diastolic periods of fetal heart motion. Linear regression analysis was used to assess the relationship between the fetal thymus volume and gestational age. Paired Student t tests were used to evaluate both the level of agreement for interobserver and intraobserver variability and the difference between diastolic and systolic thymus volumes. RESULTS: Identification of the borders of the thymus and calculation of its volume were successful in 28 patients (77.7%). Statistically significant linear growth of the thymus during pregnancy, from 12 to 35 weeks, was found. The growth coefficient for each gestational age was 0.43 (95% confidence interval, 0.355 to 0.504; P < .001). The difference in thymus size between systole and diastole was minor (0.0798 cm(3); 95% confidence interval, -0.044 to 0.203 cm(3)). Interobserver and intraobserver variability was not statistically significant. CONCLUSIONS: Although the thymus has a complex shape, it was possible to determine its borders and to calculate its volume by virtual organ computer-aided analysis in 77.7% of cases. Linear growth during pregnancy was found, and the minor changes during systole and diastole could be explained by condensation of the soft tissue of the thymus secondary to cardiac activity.

Early visualization and measurement of the pericallosal artery: an indirect sign of corpus callosum development.

OBJECTIVES: The purpose of this study was to evaluate the feasibility of visualization and measurement of the pericallosal artery during early stages of gestation. METHODS: The study group comprised 80 pregnant women between 12 and 21 weeks' gestation who attended our ultrasound unit. Transabdominal or transvaginal sonography was performed to obtain the optimal angle of a midsagittal section. High-definition flow power Doppler imaging was used to visualize the pericallosal artery. In a sagittal plane, the lengths of the pericallosal artery were measured using a straight line to connect the most anterior and posterior points. All patients were reexamined at a later stage of pregnancy to verify the existence of the corpus callosum and pericallosal artery. RESULTS: Visualization of the pericallosal artery was evident in 71 fetuses, in all of whom the biparietal diameter was greater than 20 mm. We were able to verify normal anatomy and the existence of the pericallosal artery in these fetuses between 30 and 32 weeks' gestation. A positive linear association was found between the length of the pericallosal artery and the gestational age (R(2) = 0.95) and the biparietal diameter at each gestational age (R(2) = 0.99). CONCLUSIONS: Our data show that it is feasible to visualize and measure the pericallosal artery from an early stage of gestation, and this measurement could be an indirect indication of normal corpus callosum development.

Vermian biometric parameters in the normal and abnormal fetal posterior fossa: three-dimensional sonographic study.

OBJECTIVES: The purposes of this study were to describe a 3-dimensional sonographic technique for evaluation of the fetal vermis and to compare vermian biometric parameters in fetuses with a normal and an abnormal posterior fossa. METHODS: A prospective study was conducted from 2006 through 2008 on 12 fetuses with an abnormal posterior fossa and 73 healthy control fetuses from 18 to 35 weeks' gestation. Three-dimensional scans of the fetal head were performed in the axial plane, using static volume contrast imaging in the C-plane. The vermian perimeter, cross-sectional area, and superoinferior diameter were measured and compared between abnormal and normal fetuses using the Wilcoxon nonparametric test. Linear regression analysis was used to describe trends of the vermis during gestation. The z scores for perimeter, cross-sectional area, and superoinferior diameter measurements in the abnormal posterior fossa group in each 2-week interval were calculated. RESULTS: Twelve fetuses with an abnormal posterior fossa were recruited: 3 with a Blake pouch cyst, 1 vermian cyst, 1 enlarged cisterna magna, 2 Dandy-Walker malformation, 4 partial vermian agenesis, and 1 hemicerebellar hypoplasia. The vermian cross-sectional area was reduced significantly in the fetuses with an abnormal posterior fossa compared with the control fetuses starting at 18 to 19 weeks' gestation (P = .01); the mean vermian superoinferior diameter was lower only from 22 to 23 weeks (P = .01); and the mean vermian perimeter was decreased from 28-29 weeks' gestation (P = .03). Linear regression analysis of the parameters showed that fetuses with an abnormal posterior fossa had a statistically significantly lower growth rate than control fetuses during gestation (P < .001). CONCLUSIONS: Measurements of the cross-sectional area were more useful than those of the perimeter and superoinferior diameter in distinguishing between fetuses with a normal and an abnormal posterior fossa during the early stages of gestation.

Miniaturizing bromodeoxyuridine incorporation enables the usage of flow cytometry for cell cycle analysis of adherent tissue culture cells for high throughput screening.

Analysis of cell cycle progression by 5-bromo-2'-deoxyuridine (BrdU) incorporation is commonly used for evaluating the mode of action of anticancer drugs, but usually requires a high number of cells and large amounts of monoclonal antibodies. In addition, manual sample handling is not suitable for high throughput. To circumvent these limitations, we have developed a miniaturized method to measure BrdU incorporation into DNA directly in 96-wells plates. Adherent cells were grown in 96-well plates in the absence or presence of compounds of interest. After BrdU pulse labeling or pulse chase, cells were harvested, transferred to polymerase chain reaction (PCR) V-bottom plates, and fixed by adding methanol. DNA denaturation was performed directly in the plates by heat using a PCR thermocycler. BrdU incorporation was detected by indirect immunocytochemical staining, and cellular DNA was counterstained using propidium iodide. Samples were acquired by a BD FACSCalibur with BD Multiwells Auto sampler or BD HTS. We defined a dynamic range of the optimal cell number, for which cells maintained exponential growth up to 72 h. The assay was robust up to 30,000 cells per well. BrdU dot plots of cell cycle phases showed an excellent separation of cell populations, and DNA histograms showed a low coefficient of variation. Thermal denaturation was suitable for 96-well plates to detect BrdU incorporation with a good signal-to-noise ratio, and cluster analysis allowed fingerprint readouts for drug sensitivity and mechanism of action as exemplified for paclitaxel and doxorubicin. This method provided rapid high-throughput BrdU/DNA content analysis with high accuracy and reproducibility, accompanied by a reduction in reagent consumption. A critical step was identified as the standardization of DNA denaturation using a PCR thermocycler. Here,we show some applications of this method for cell cycle studies in drug discovery.

A model-based approach to the in vitro evaluation of anticancer activity.

PURPOSE: The use of in vitro screening tests for characterizing the activity of anticancer agents is a standard practice in oncology research and development. In these studies, human A2780 ovarian carcinoma cells cultured in plates are exposed to different concentrations of the compounds for different periods of time. Their anticancer activity is then quantified in terms of EC(50) comparing the number of metabolically active cells present in the treated and the control arms at specified time points. The major concern of this methodology is the observed dependency of the EC(50) on the experimental design in terms of duration of exposure. This dependency could affect the efficacy ranking of the compounds, causing possible biases especially in the screening phase, when compound selection is the primary purpose of the in vitro analysis. To overcome this problem, the applicability of a modeling approach to these in vitro studies was evaluated. METHODS: The model, consisting of a system of ordinary differential equations, represents the growth of tumor cells using a few identifiable and biologically relevant parameters related to cell proliferation dynamics and drug action. In particular, the potency of the compounds can be measured by a unique and drug-specific parameter that is essentially independent of drug concentration and exposure time. Parameter values were estimated using weighted nonlinear least squares. RESULTS: The model was able to adequately describe the growth of tumor cells at different experimental conditions. The approach was validated both on commercial drugs and discovery candidate compounds. In addition, from this model the relationship between EC(50) and the exposure time was derived in an analytic form. CONCLUSIONS: The proposed approach provides a new tool for predicting and/or simulating cell responses to different treatments with useful indications for optimizing in vitro experimental designs. The estimated potency parameter values obtained from different compounds can be used for an immediate ranking of anticancer activity.

Age-specific risk of fetal loss post second trimester amniocentesis: analysis of 5043 cases.

OBJECTIVES: To assess the risk of fetal loss attributable to second trimester amniocentesis in singleton pregnancies through a cross-sectional study. METHODS: Records of 5043 consecutive second trimester amniocentesis, performed by a single operator between 1997 and 2003, were analyzed. Fetal loss post amniocentesis was calculated by grouping pregnant women in age classes and assessing observed/expected (O/E) rate. RESULTS: Total fetal losses were 40 (0.81%): 33 cases (0.67%) occurred before the 24th week, 37 cases (0.76%) before the 28th gestational week, and 3 cases (0.06%) after the 28th week of pregnancy. An age-dependent increase of the rate of fetal loss, not statistically significant (Chi-Square = 0.349, p = 0.505) was observed. The total O/E ratio values did not show any statistically significant risk (O/E ratio = 1.25, CI = 0.86-1.64). The analysis of the single age classes did not detect any statistical significance. The excess fetal loss rate associated with amniocentesis was 0.16%. CONCLUSIONS: No effect of the 2nd trimester amniocentesis was noted on fetal loss.