Fetal and Infant Growth Patterns and Kidney Function at School Age

Low birth weight is associated with ESRD. To identify specific growth patterns in early life that may be related to kidney function in later life, we examined the associations of longitudinally measured fetal and infant growth with kidney function in school-aged children. This study was embedded in a population-based prospective cohort study among 6482 children followed from fetal life onward. Fetal and childhood growth was measured during second and third trimesters of pregnancy, at birth, and at 6, 12, 24, 36, and 48 months postnatally. At the age of 6 years, we measured kidney volume by ultrasound. GFR was estimated using blood creatinine levels. Higher gestational age-adjusted birth weight was associated with higher combined kidney volume and higher eGFR (per 1 SD score increase in birth weight; 1.27 cm³ [95% confidence interval, 0.61 to 1.93] and 0.78 ml/min per 1.73 m² [95% CI, 0.16 to 1.39], respectively). Fetal weight, birth weight, and weight at 6 months were positively associated with childhood kidney volume, whereas higher second trimester fetal weight was positively associated with higher GFR (all P values<0.05). Fetal and childhood lengths were not consistently associated with kidney function. In this cohort, lower fetal and early infant weight growth is associated with smaller kidney volume in childhood, whereas only lower fetal weight growth is associated with lower kidney function in childhood, independent of childhood growth. Whether these associations lead to an increased risk of kidney disease needs to be studied further.Low birth weight is associated with higher risks of ESRD and hypertension in later life.^1–3 Clearly, low birth weight is not the causal factor per se leading to kidney diseases in later life. Birth weight is the result of various exposures and growth patterns in fetal life and the starting point of childhood growth. It has been hypothesized that especially third trimester fetal growth restriction leads to persistently smaller kidneys with a reduced number of nephrons, which may predispose the individual to kidney disease in adulthood.^4–6 This hypothesis is supported by both animal and human studies, showing that kidney volume and nephron number are reduced in fetal growth-restricted subjects and hypertensive subjects.^7–9 Although nephrogenesis is known to continue until 36 weeks of gestation and cease thereafter, not much is known about the specific critical periods and early growth patterns related to kidney function in later life.¹⁰ Also, whether and to what extent the associations of low birth weight with CKD are explained by preterm birth are not known.¹ Longitudinal studies suggested that the associations of low birth weight with hypertension were stronger in subjects with rapid weight gain in childhood, but results are inconclusive.^11,12 A similar growth pattern has not been identified as a risk factor for kidney diseases yet.Prospective studies linking fetal and early childhood growth patterns to kidney outcomes in later life might help to identify early critical periods for developing impaired kidney function in later life.Therefore, we examined, in a population-based prospective cohort study among 6482 children followed from early fetal life onward (Figure 1), the associations of birth weight, gestational age, birth weight for gestational age, and longitudinally measured fetal and early childhood growth patterns with kidney size and function at school age. We used subclinical variations of kidney function in childhood as outcomes, because they relate to kidney disease in later life.¹³Open in a separate windowFigure 1.Flow chart: exclusion criteria and numbers of participants are given. Total numbers of available outcome measurements are given.     

Supero-inferior ventricles and hearts with crossed circulation. Apropos of 2 cases. Review of the literature

Two cases of supero-inferior heart are reported. Segmental analysis of the first case showed: situs solitus, atrioventricular (left sided loop) and ventriculoarterial discordance, resulting in a corrected transposition with the aorta in L malposition. The second malformation arose on a situs inversus, atrioventricular concordance (left sided loop) and double outlet right ventricle. The right ventricle was on the right and above the left ventricle giving an appearance of paradoxal discordance. The atrioventricular connections determined a plane of cleavage between right and left circulations in the supero-inferior ventricles and an appearance of crossed circulations in the second case. Hypoplasia of the inflow tract, of the right ventricular sinus is almost constant in this type of spatial orientation of the ventricles. The embryological hypoplasias are suggestive of an abnormality in the rotation of the cardiac tube in a frontal plane for the superimposed ventricles and abnormal rotation secondary to ventricular septation in the hearts with crossed circulations. The different classifications proposed in the literature are discussed with respect to these cases.     

Hormonal requirements for growth and differentiation of ob17 preadipocyte cells in vitro

The ob17 cell line is a clonal line established from epididymal fat pads of C57 BL/6J ob/ob mice. After conversion into adipose-like cells, ob17 presents both the morphological and biochemical properties of mature rodent fat cells. The adipose conversion process is best represented by a stochastic model in which a pool of stem cells (adipoblasts) gives rise to clusters of adipose cells and to additional stem cells that remain in the population. The role of the different factors involved in the adipose conversion process of ob17 cells is discussed, i.e. 1) mitogenic factors, that enhance the number of committed cells (ACF or adipose conversion factor(s)) 2) lipogenic factors, that enhance the expression of adipocyte enzyme markers (insulin) and 3) adipogenic factors, that are obligatory requirements for adipose conversion (triiodothyronine, growth hormone and other pituitary factors).     

Studies of the factors modulating antidiuretic hormone excretion in man in response to the osmolar stimulus: effects of oestrogen and angiotensin II

The aim of this study was to assess the influence of hormones known to regulate fluid and electrolyte balance on the release of antidiuretic hormone induced by raising serum osmolality. The stimulus provoked by the infusion of a 2.5% NaCl solution induces an increase of urinary [arginine-8]-vasopressin from 1.12 to 2.64 ng/h in men and from 1.65 to 7.27 ng/h in women as has been previously reported. These results were compared to those obtained in males infused with angiotensin II (AII) before and during a hypertonic sodium load and in males infused with hypertonic saline on the fourth day of administration of ethinyl-oestradiol. During the combined infusion of AII and then hypertonic saline, the mean hourly urinary excretion of AVP increased from 2.8 to 5.67 ng/h. Within each group the increase of urinary AVP was highly significant. The rise of urinary AVP during AII infusion was significantly different from the rise observed both in untreated males and untreated females, lying in between. The mean hourly excretion rate of AVP increased before and after hypertonic saline loading from 2.65 to 5.3 ng/h in males pre-treated with ethinyl-oestradiol. The significant difference observed between males and females is reduced when males treated with oestrogen were compared to female subjects. In each group plasma renin activity decreased to low values during the salt-loading test. During oestrogen treatment PRA and plasma renin substrate rose, while urinary aldosterone remained almost unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)     

Antiinflammatory Effects of Murine Malignant Cells

Development of teratocarcinoma does not impair immunization of mice against Listeria monocytogenes. Endotoxin injection a short time before tumor cell inoculation allows the growth of teratocarcinoma in non syngenic mice despite immune stimulation. In contrast with this absence of impaired systematic immunity, teratocarcinoma cells were found to repulse macrophages in vitro. This effect on macrophages was also found with three other malignant cells and with trophoblast cells. In vivo, teratocarcinoma cells were found to impair local inflammation. These cells and other malignant cells are able to produce a compound(s) of molecular weight between 10(3) and 10(4), which prevents inflammatory reaction. These results suggest that mouse teratocarcinomas and other tumors by-pass the host immunological system of surveillance by at least two mechanisms: a direct toxic effect on macrophages and the release of an inhibitor of inflammation. The possible relations between these properties of malignant cells and physiological functions of trophoblast are discussed.     

Multiplexed barcoded CRISPR-Cas9 screening enabled by CombiGEM

The orchestrated action of genes controls complex biological phenotypes, yet the systematic discovery of gene and drug combinations that modulate these phenotypes in human cells is labor intensive and challenging to scale. Here, we created a platform for the massively parallel screening of barcoded combinatorial gene perturbations in human cells and translated these hits into effective drug combinations. This technology leverages the simplicity of the CRISPR-Cas9 system for multiplexed targeting of specific genomic loci and the versatility of combinatorial genetics en masse (CombiGEM) to rapidly assemble barcoded combinatorial genetic libraries that can be tracked with high-throughput sequencing. We applied CombiGEM-CRISPR to create a library of 23,409 barcoded dual guide-RNA (gRNA) combinations and then perform a high-throughput pooled screen to identify gene pairs that inhibited ovarian cancer cell growth when they were targeted. We validated the growth-inhibiting effects of specific gene sets, including epigenetic regulators KDM4C/BRD4 and KDM6B/BRD4, via individual assays with CRISPR-Cas–based knockouts and RNA-interference–based knockdowns. We also tested small-molecule drug pairs directed against our pairwise hits and showed that they exerted synergistic antiproliferative effects against ovarian cancer cells. We envision that the CombiGEM-CRISPR platform will be applicable to a broad range of biological settings and will accelerate the systematic identification of genetic combinations and their translation into novel drug combinations that modulate complex human disease phenotypes.New therapeutic strategies are needed to treat complex human diseases. Because disease phenotypes are often regulated by interwoven genetic networks, exploiting combination therapy to target multiple pathways, as opposed to only single ones, can enhance treatment efficacy (1). However, discovering effective combination therapies for human diseases is challenging with existing methods, due to the cost, effort, and labor required to construct and analyze each combination (2). For example, the National Cancer Institute tested ∼5,000 pairwise combinations of 100 cancer drugs against the NCI-60 panel in a study that took 2 y and cost about USD $4 million (3). Thus, there is a need for technological advances to accelerate the identification of effective combinatorial therapies. Here, we used our combinatorial genetics en masse (CombiGEM)-CRISPR platform to perform rapid pooled screening of pairwise genetic knockouts against genes coding for epigenetic regulators and then translated our screen hits into drug combinations against human ovarian cancer cells.CRISPR-Cas9 technology has been used for large-scale genetic perturbation screens with single-guide RNA (sgRNA) libraries for gene knockouts (4–7), repression, and activation (8, 9). Despite its simplicity for multiplexed genetic perturbations (10–12), new methods are needed to enable high-throughput CRISPR-Cas9–based screening with combinatorial sets of guide RNAs (gRNAs), which would be broadly useful for studying combinatorial gene functions in multigenic phenotypes and diseases. By using CombiGEM-based DNA assembly (13, 14), we developed a strategy for the simple and efficient assembly of barcoded combinatorial gRNA libraries. These libraries can be delivered into human cells by lentiviruses to create genetically ultradiverse cell populations harboring unique gRNA combinations that can be tracked via barcode sequencing in pooled assays. This strategy, termed CombiGEM-CRISPR, uses one-pot cloning steps to enable the assembly of combinatorial gRNA libraries, thus simplifying and accelerating the workflow toward systematic analysis of combinatorial gene functions.     

Acellular pertussis vaccine based on outer membrane vesicles capable of conferring both long-lasting immunity and protection against different strain genotypes

Despite high vaccination coverage rates, pertussis continues to be a global concern, with increased incidence widely noted. The current pertussis epidemiologic situation has been mainly attributed to waning immunity and pathogen adaptation. To improve the disease control, a new generation of vaccines capable to overcome those weaknesses associated to the current vaccines need to be developed. Previously we have demonstrated that the outer membrane vesicles obtained from the recombinant Bordetella pertussis strain expressing PagL enzyme (OMVs_BpPagL) are good vaccine candidates to protect against pertussis. In this work the OMVs_BpPagL formulated with diphtheria and tetanus toxoids (Tdap_OMVsBpPagL) was used to evaluate its capacity to offer protection against Argentinean clinical isolates and to induce long-term immunity. To these aims BALB/c mice were immunized with Tdap_OMVsBpPagL and challenged with sublethal doses of the clinical isolate Bp106 selected as a representative circulating isolate. Comparisons with a current commercial Tdap vaccine used at a dose in which pertussis toxin level was equivalent to that of Tdap_OMVsBpPagL were performed. With the normalized doses of both vaccines we observed that Tdap_OMVsBpPagL protected against the clinical isolate infection, whereas current commercial Tdap vaccine showed little protection against such pathogen. Regarding long-term immunity we observed that the Tdap_OMVsBpPagL protective capacity against the recommended WHO reference strain persisted at least 9 months. In agreement with these results Tdap_OMVsBpPagL induced Th1 and Th2 immune response. In contrast, commercial Tdap induced Th2 but weak Th1 responses. All results presented here showed that Tdap_OMVsBpPagL is an interesting formulation to be considered for the development of novel acellular multi-antigen vaccine.