Appearance Of Phenotype Research Articles

Conflict between morphological and molecular data: A case study of Ficus krishnae (Moraceae)

Ficus krishnae, considered as highly sacred plant species in India, is well known for its peculiar nature of cup-shaped leaves. The species distinctly differs from its allied species F. benghalensis not only in the cup formation in leaves but also in the height of plants, aerial roots, stipules, petiole and its leafy appendages, ostiolar bracts of the receptacle and pollinator wasps, in addition to slight differences in the karyotype, DNA contents, stomatal and parenchymatous cells and nodal anatomy. In spite of having several morphological differences, F. krishnae is considered by some authors as a synonym of F. benghalensis, which does not seem to be convincing. Contrary to the morphological differences, the sequence analysis of nuclear and plastid regions of both the species conducted in the present study does not reveal any significant variations and thus infers no differentiation between the species at molecular level. This may be due to mutations at one or few coding loci or differences in gene expression associated with morphogenesis with significant phenotypic appearance.

21-Hydroxylase deficiency-induced congenital adrenal hyperplasia in 230 Chinese patients: Genotype–phenotype correlation and identification of nine novel mutations

Steroid 21-hydroxylase deficiency (21-OHD) caused by the CYP21A2 gene mutations accounts for more than 90% of congenital adrenal hyperplasia (CAH) cases. In this study, molecular defects of 230 patients with 21-OHD were investigated. Point mutations of CYP21A2 gene were analyzed by Sanger sequencing, and large gene deletions were detected by multiplex ligation-dependent probe amplification (MLPA). Nine micro-conversions and 18 spontaneous mutations accounted for 74.6% of alleles, while large gene deletions and large gene conversions accounted for 25.4% of alleles. The most frequent micro-conversion was c.292-13A/C>G (I2G) (35%), followed by p.I173N (14.3%), p.R357W (5.9%) and p.Q319∗ (4.6%). Nine novel mutations were identified in these patients, which were predicted to hamper the 21-hydroxylase protein function in varying degrees. Genotype and phenotype correlated well in 89.6% of our patients, but disparity in phenotypic appearance also appeared in a small portion of the patients. 16.1% of the patients carried homozygous genotypes while 83.9% of patients carried compound heterozygous mutations. We concluded that the frequency of CYP21A2 mutations in our study was slightly different from those reported for other ethnic groups. Micro-conversions were the main category of the mutation spectrum, while large deletions and large gene conversions could also cause 21-OHD. A large portion of different types of the compound heterozygous genotypes may partially contribute to the discordance in genotype–phenotype comparison. This study expanded the CYP21A2 mutation spectrum of Chinese patients and could be helpful in prenatal diagnosis and genetic counseling for 21-OHD patients.

Abstract A10: High-fat diet enhances MYC-driven prostate cancer through epigenomic and metabolomic rewiring

Abstract Diet is hypothesized to be a critical environmental risk factor for prostate cancer (PCa) development, and progression; however, the mechanisms underlying these associations remain elusive. In a MYC-driven PCa mouse model we find that a high fat diet significantly alters the transcription of genes implicated in chromatin function and remodeling in prostatic tumor tissues but not in the normal prostate. Importantly, this chromatin associated gene expression signature was observed well before the appearance of a high fat diet-driven phenotype that was characterized by greater cell proliferation and increased tumor burden. Consistent with this finding, high-throughput targeted quantitative histone mass spectrometry revealed a robust MYC-driven signature affecting more than half of the 68 histone marks profiled. Surprisingly, high fat diet further enhanced the MYC-induced epigenetic signature while it was unable to affect the normal murine prostate. Epigenetic remodeling relies on substrates and cofactors that are obtained from the diet. Untargeted metabolomic analyses revealed that MYC overexpression, as expected, impacted glutamine uptake. In addition, high fat diet leads to additional carbohydrates, amino acids, lipids and nucleotides necessary to sustain an increased cellular proliferation in MYC-driven cancers while it had little influence on the normal prostate. Moreover, the pool of metabolites altered by high fat diet in the context of MYC overexpression is highly suggestive of a global methylation defect. Finally, using the genome-wide mRNA profiles of tumor (N=402) and adjacent normal (N=200) prostate tissues from the Health Professionals Follow-up Study and the Physicians' Health Study cohorts, we have discovered an enrichment in genes implicated in chromatin function and remodeling in tumor tissues from overweight/obese men, but not in normal adjacent tissues, consistent with the high fat diet signature observed in mice. Strikingly, men whose tumors had high expression of this chromatin signature had worse clinical characteristics and were more likely to die from prostate cancer (OR = 5.01; 95% CI = 2.31, 11.38 comparing extreme score quartiles). Taken together, these results demonstrate that a high fat diet does not drive significant epigenomic and metabolomic alterations in the normal prostate while it leads to important alterations in MYC-driven PCa that results in increased aggressiveness. Our results suggest that the impact of diet on PCa risk may be to augment the growth of already established subclinical disease. In addition, as MYC is one of the most commonly amplified genes in PCa, the ability of a high fat diet to augment MYC-driven cancers in this pre-clinical model suggest that a healthy diet may slow the progression of the disease. Citation Format: David P. Labbé, Giorgia Zadra, Ericka M. Ebot, Charles Y. Lin, Jaime M. Reyes, Stefano Cacciatore, Maura Cotter, Amanda L. Creech, Jacob D. Jaffe, Philip W. Kantoff, James E. Bradner, Lorelei A. Mucci, Massimo Loda, Myles Brown. High-fat diet enhances MYC-driven prostate cancer through epigenomic and metabolomic rewiring. [abstract]. In: Proceedings of the AACR Special Conference on Chromatin and Epigenetics in Cancer; Sep 24-27, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2016;76(2 Suppl):Abstract nr A10.

Antibacterial Activity of Medicinal Plant (Centauraea Calcitrapa) against Multi-Drug Resistant Bacteria (MDRB)

The present study was conducted to evaluate the antibacterial activity of Centauraea calcitrapa against multidrug resistant bacteria (Staphylococcus aureus, Enterococcus faecium, klebsiella pneumoniae, Acinetobacter baumanni, Enterobacter cloacae and Pseudomonas aeruginosa) , purify and identify the active compounds. A sensitivity test was performed using disc diffusion method that resulted in the appearance of multiple drug resistance phenotypes of tested bacteria. Antibacterial activity of Centauraea calcitrapa showed that inhibition zone diameter against Staphylococcus aureus (23mm), Enterococcus faecium (17mm) , Klebsiella pneumoniae (15mm), Acinetobacter baumanni (22mm), Enterobacter cloacae (20mm) and Pseudomonas aeruginosa (18mm) . Highest activity was exhibited against Staphylococcus aureus and can be considered to be more effective than the most commercial antibiotics. The active compound was purified using column chromatography and visualized using thin layer chromatography (TLC). The Minimum inhibitory concentration (MIC) values of active purified compound ranged from 15.6 to 62.5μg/ml. Minimum bactericidal concentrations (MBC) values were two-fold higher than the corresponding MIC values ranged from 31.25 to 125μg/ml. The active purified compound was partial identified using UV, IR, 1HNMR and mass spectroscopy. The analysis of data obtained indicated that; the purified active compound belongs to janerin group of chemical compounds. (Centauraea calcitrapa) is a new source for discovery of bio-active compound against (MDRB).

The correlation between PLC-β2 and miR-146a in breast ductal carcinoma in situ (DCIS) defines its malignant potential

Ductal carcinoma in situ (DCIS), which represents the most frequently diagnosed tumor in women in industrialized countries, may be a crucial step in the progression of breast lesions to invasive ductal carcinoma (IDC) (1). Among the signaling molecules deregulated in breast tumors, the beta2 isoform of the phosphoinositide-dependent phospholipase C (PLC-b2) strongly correlates with malignancy of invasive tumors and breast tumor-derived cells (2, 3). In breast tumor-derived cell lines cultured under hypoxia, PLC-b2 regulates the levels of cancer stem cell and epithelial-to-mesenchymal transition (EMT) markers (4), suggesting its involvement in breast cancer progression. By using archival FFPE breast tumor samples, we demonstrated that PLC-β2 is up-regulated in DCIS, in which it inversely correlates to the levels of miR-146a, known to act as a tumor suppressor in breast cancer (5). By using the MCF10DCIS cell line, a well-established model of DCIS-derived cells, we demonstrated that the de-regulation of miR-146a is sufficient to modulate the expression of PLC-β2, in turn able to affect the epithelial-to-mesenchymal shift as well as the number of cells expressing CD133. These data indicate that miR-146a and PLC-β2 are members of an intracellular network able to ensure the maintenance of the non-invasive phenotype of DCIS and suggest that alterations in their levels can determine the appearance of an invasive phenotype. The potential prognostic relevance of PLC-β2/miR-146a relationship was investigated in primary DCIS from patients who developed an invasive ductal carcinoma in the contralateral breast. The PLC-β2/miR-146a correlation was found negative in primary DCIS from patients who did not recur and strongly positive in DCIS from patients who developed a contralateral IDC. We propose that the assessment of the correlation between the levels of PLC-β2 and miR-146a in primary DCIS at diagnosis could be beneficial to identify patients with either low or high propensity to develop invasive recurrence. Since a major problem in the management of patients with DCIS is the lack of reliable prognostic markers, our results might be of value in selecting the most appropriate therapies for individual women with non-invasive breast neoplasia.

Mechanisms involved in extracellular matrix remodeling and arterial stiffness induced by hyaluronan accumulation

Background and aimsHyperglycemia induces hyaluronan (HA) accumulation in the vasculature. Excessive accumulation of HA around the vascular smooth muscle cells (VSMC) results in increased aortic stiffness and strength and accelerated atherosclerosis in ApoE−/− mice. We hypothesized that HA accumulation primes the vasculature for atherosclerosis by crosslinking and reorganizing the extracellular matrix (ECM) and by pushing VSMC differentiation towards a less mature phenotype. MethodsAortas from HAS-2 transgenic (Tg) mice and wild type mice were used for all experiments. Biomechanics and cross-sectional area measurements were performed before and after HA digestion. The vessel and ECM composition was examined by immunoblotting and electron microscopy. Primary VSMC cultures were examined by qPCR and thymidine incorporation. ResultsTg mice aorta cross-sectional area was increased before (14%, p = 0.0148), but not after HA digestion (p = 0.3437). The increase in vessel stiffness (32%, p = 0.0217) and strength (31%, p = 0.0043) in the Tg aorta persisted after HA digestion. Crosslinking of HA by heavy chains from Inter-α-Inhibitor was increased (175%, p = 0.0006). The Tg VSMCs have the appearance of a synthetic phenotype supported by a 40% decrease in α-smooth muscle actin isoform X1 (p = 0.0296) and an increase in proliferation (63%, p = 0.0048) and osteoprotegerin production (133%, p = 0.0010) in cultured Tg VSMCs. ConclusionsOur results show that induced HA accumulation is followed by increased HA crosslinking and create a shift in VSMC phenotype and proliferation. These findings may provide a mechanism for how hyperglycemia through HA accumulation prime the vascular wall for cholesterol and leucocyte accumulation and development of atherosclerosis.

An emerging interplay between altered human lipid metabolism, lipodystrophy and aging

LMNA -Lipodystrophies are a group of heterogeneous syndromes, with either genetic or acquired origin, characterized by the accumulation of prelamin A, an inmature form of the protein lamin A, one of the major components of the nuclear lamina. Several molecular studies suggest lamin A is involved in adipocyte development, the disruption of which leads to compromised regulation of adipogenesis, adipocyte lipid droplet formation and maintenance, and subsequent secondary dysfunctions in fat metabolism. Moreover, these diseases clinically present with generalized or partial fat atrophy connected with metabolic complications, such as insulin-resistant diabetes and dyslipidemia, in addition to age associated manifestations. There is a real need to increase our understanding regarding these syndromes because of their import in human health and the lack of knowledge of their etiopathology. To gain deeper insights into these metabolic diseases, we have taken advantage of a previously generated “disease in a dish” model of human LMNA -lipodystrophy based on the pathological accumulation of the precursor prelamin A in stem cell derived adipocytes. This experimental model recapitulates phenotypes observed in lipodystrophic patient’s samples and animal models, and it has been critical in elucidating new insights into the molecular mechanisms governing this set of disorders. Recently, we have identified alterations in fundamental processes of lipid homeostasis such as lipolysis, as well as mitochondrial and endoplasmic reticulum functions, similar to what can be observed in some metabolic and aging phenotypes. Additionally, the lipidomic profile of this lipodystrophic experimental model displayed a lipid metabolic signature similar to aging systems, providing new information concerning metabolic pathways affected during the aging process. By clarifying the fundamental mechanisms governing these aging associated diseases, future novel interventions could be developed that will at least delay the appearance of aging phenotypes and thereby increase the healthspan or disease-free time of an individual.

Re-description of Apistogramma payaminonis KULLANDER, 1986, with descriptions of two new cichlid species of the genus Apistogramma (Teleostei, Perciformes, Geophaginae) from northern Peru

Apistogramma payaminonis Kullander, 1986 is redescribed based on the only two type specimens available, and two new, closely-related Apistogramma species are described from Peru. Data from the original description of A. payaminonis are supplemented with information on phenotypic appearance, which is important for differentiating the taxon from several other species discovered in the last few years. Apistogramma feconat sp. n. is described from four specimens from the catchment of the Río Tigre, Loreto; information on its ecology, biology, and current conservation status is summarised. Apistogramma wolli sp. n. is described from six specimens from the catchment of the Napo river, Loreto, close to the Peru-Ecuador border; information on its ecology and biology is sparse. Both newly described species are representatives of the Apistogramma nijsseni complex that live in small forest streams influenced by blackwater. Information on differentiating females of some members of this group of related species is presented. At present no clear information based on voucher specimens is available regarding the possible distribution of the two species in Ecuador. Man-made environmental hazards potentially endangering the aquatic fauna in the western catchment of the Río Marañón and the Rio Amazonas, between their tributaries the Rio Pastaza and the Rio Napo, are discussed.

Molecular basis of D-negative phenotype (literature review and case reports)

The molecular basis of the D-negative phenotype formation in humans is presented in this article. Causes of true and false D-negative phenotype appearance are described. The basis of true D-negative phenotype are changes in the genome, that lead to complete lack of RhD antigen expression on the red blood cells surface, or defective expression of RhD antigen, not detectable by serological methods. The reason for the false D-negative phenotype is the insufficient sensitivity of routine serological methods. Cases of true and false D-negative phenotype identified during the examination of the Russia residents are described. We were able to identify one case of true (RHDψ) and five cases of false D-negative phenotype (RHD weak type 2 – two cases, RHD weak type 15 – one case and RHD weak type 20 – two cases) by molecular method.

Human papillomavirus genotypes and clinical management of genital warts in women attending a colposcopy clinic in Cape Town, South Africa.

Genital human papillomavirus (HPV) infection is the most common sexually transmitted viral disease in the world. HPV infection of the genital epithelium is associated with genital warts and malignancies of the lower genital tract. To describe the distribution, phenotypic appearance and HPV type associated with genital warts in women. This was a prospective observational study of all women with genital warts who attended the Colposcopy Clinic, Groote Schuur Hospital, Cape Town, South Africa, during 2010 and fulfilled the inclusion and exclusion criteria. One hundred and thirteen women were tested for HPV using the Roche Linear Array HPV genotyping kit to determine the HPV genotypes causing genital warts. The median age of the women was 27 years (range 15 - 53); 90 (79.6%) were HIV-positive, and two-thirds were on antiretroviral treatment. Treatment involved ablation with topical agents, cauterisation or carbon dioxide laser. At 3 months' follow-up after treatment, 56.6% of the women, the majority of whom were HIV-positive, had recurrent/persistent disease. In both HIV-positive and HIV-negative women, HPV was detected in over 90% of cases. However, over half the HIV-positive women as opposed to 2/18 of the HIV-negative women were infected with multiple HPV genotypes. The commonest HPV genotypes in HIV-positive and HIV-negative women were types 11, 6, 89, 61, 55 and 62 and types 11 and 6, respectively. The majority of the patients were HIV-positive and had multiple HPV infections. While this did not alter the phenotypic appearance of the warts, recurrence/persistence after treatment was more common.

NO is involved in spermidine-induced drought tolerance in white clover via activation of antioxidant enzymes and genes.

Nitric oxide (NO), a key signaling molecule, can be induced by polyamines (PAs), which play an important role in improving drought tolerance in plants. This study was to further investigate the role of NO in spermidine (Spd)-induced drought tolerance associated with antioxidant defense in leaves of white clover (Trifolium repens) under drought stress induced by -0.3MPa polyethylene glycol (PEG-6000) solution. A hydroponic growth method was used for cultivating plants in a controlled growth chamber for 30-33days until the second leaves were fully expanded. Two relative independent experiments were carried out in our study. One is that exogenous application of Spd or an NO donor (sodium nitroprusside (SNP)) significantly improved drought tolerance in whole plants, as demonstrated by better phenotypic appearance, increased relative water content (RWC), and decreased electrolyte leakage (EL) and malondialdehyde (MDA) content in leaves as compared to untreated plants. For another detached leaf experiment, PEG induced an increase in the generation of NO in cells and significantly improved activities of nitrate reductase (NR) and nitric oxide synthase (NOS). These responses could be blocked by pre-treatment with a Spd biosynthetic inhibitor, dicyclohexyl amine (DCHA), and then reversed by application of exogenous Spd. Meanwhile, PEG induced up-regulation of activities and gene transcript levels of corresponding antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) to varying degrees, while these effects were partially blocked by pre-treatment with DCHA, the scavenger of NO, the inhibitors of NR or NOS. In addition, Spd-induced antioxidant enzyme activities and gene expression also could be effectively inhibited by an NO scavenger as well as inhibitors of NR and NOS. These findings suggest that both Spd and NO can enhance drought tolerance. Spd was involved in drought stress-activated NR and NOS pathways associated with NO release, which mediated antioxidant defense and thus contributed to drought tolerance in white clover.

Asian American phenotypicality and experiences of psychological distress: More than meets the eyes.

Research on Asian Americans’ experiences of racism has examined the impact of generation status and ethnicity. This study investigates how phenotypic and physical appearance characteristics are implicated in self-reports of racialization and social anxiety in Asian American college students (n 170) who completed measures of psychological distress, well-being, and racialization (e.g., Subtle and Blatant Racism Scale; Yoo, Steger, & Lee, 2010). Participants’ digital photographs were analyzed to test whether specific physical characteristics correlated with self-reported distress. Results suggest eyeglasses and darker skin tone are strongly associated with greater reports of racialization and psychological distress in Asian American college students.

Phytochrome B Mediates the Regulation of Chlorophyll Biosynthesis through Transcriptional Regulation of ChlH and GUN4 in Rice Seedlings.

Accurate regulation of chlorophyll synthesis is crucial for chloroplast formation during the greening process in angiosperms. In this study, we examined the role of phytochrome B (phyB) in the regulation of chlorophyll synthesis in rice seedlings (Oryza sativa L.) through the characterization of a pale-green phenotype observed in the phyB mutant grown under continuous red light (Rc) irradiation. Our results show that the Rc-induced chlorophyll accumulation can be divided into two components—a phyB-dependent and a phyB-independent component, and that the pale-green phenotype is caused by the absence of the phyB-dependent component. To elucidate the role of the missing component we established an Rc-induced greening experiment, the results of which revealed that several genes encoding proteins on the chlorophyll branch were repressed in the phyB mutant. Notable among them were ChlH and GUN4 genes, which encode subunit H and an activating factor of magnesium chelatase (Mg-chelatase), respectively, that were largely repressed in the mutant. Moreover, the kinetic profiles of chlorophyll precursors suggested that Mg-chelatase activity simultaneously decreased with the reduction in the transcript levels of ChlH and GUN4. These results suggest that phyB mediates the regulation of chlorophyll synthesis through transcriptional regulation of these two genes, whose products exert their action at the branching point of the chlorophyll biosynthesis pathway. Reduction of 5-aminolevulinic acid (5-ALA) synthesis could be detected in the mutant, but the kinetic profiles of chlorophyll precursors indicated that it was an event posterior to the reduction of the Mg-chelatase activity. It means that the repression of 5-ALA synthesis should not be a triggering event for the appearance of the pale-green phenotype. Instead, the repression of 5-ALA synthesis might be important for the subsequent stabilization of the pale-green phenotype for preventing excessive accumulation of hazardous chlorophyll precursors, which is an inevitable consequence of the reduction of Mg-chelatase activity.

Genetic underpinnings of left superior temporal gyrus thickness in patients with schizophrenia

Objectives. Schizophrenia is a highly disabling psychiatric disorder with a heterogeneous phenotypic appearance. We aimed to further the understanding of some of the underlying genetics of schizophrenia, using left superior temporal gyrus (STG) grey matter thickness reduction as an endophenoptype in a genome-wide association (GWA) study. Methods. Structural magnetic resonance imaging (MRI) and genetic data of the Mind Clinical Imaging Consortium (MCIC) study of schizophrenia were used to analyse the interaction effects between 1,067,955 single nucleotide polymorphisms (SNPs) and disease status on left STG thickness in 126 healthy controls and 113 patients with schizophrenia. We next used a pathway approach to detect underlying pathophysiological pathways that may be related to schizophrenia. Results. No SNP by diagnosis interaction effect reached genome-wide significance (5 × 10–8) in our GWA study, but 10 SNPs reached P-values less than 10–6. The most prominent pathways included those involved in insulin, calcium, PI3K-Akt and MAPK signalling. Conclusions. Our strongest findings in the GWA study and pathway analysis point towards an involvement of glucose metabolism in left STG thickness reduction in patients with schizophrenia only. These results are in line with recently published studies, which showed an increased prevalence of psychosis among patients with metabolic syndrome-related illnesses including diabetes.

Miller-Dieker syndrome: A report of a new case and review of the literature

Miller-Dieker syndrome (MDS) is a gene deletion syndrome. It includes severe lissencephaly and a characteristic phenotypic appearance. Children with MDS also suffer from severe mental retardation, growth delay, epilepsy and occasionally hypsarrythmia on electroencephalogram. This disorder is invariably fatal in early childhood. Here, we report a new case of MDS associated with refractory atypical infantile spasms and severe mental retardation in a 3-year-old Tunisian boy. We emphasise the importance of prenatal diagnosis to avoid the recurrence of this severe handicap, particularly in the case of a familial reciprocal

Emergence of cooperation in phenotypically heterogeneous populations: a replicator dynamics analysis

The emergence of cooperation is analyzed in heterogeneous populations where two kinds of individuals exist according to their phenotypic appearance. Phenotype recognition is assumed for all individuals: individuals are able to identify the type of every other individual, but fail to recognize their own type. Individuals thus behave under partial information conditions. The interactions between individuals are described by the snowdrift game, where individuals can either cooperate or defect. The evolution of such populations is studied in the framework of evolutionary game theory by means of the replicator dynamics. Overlapping generations are considered, so the replicator equations are formulated in discrete-time form. The stability analysis of the dynamical system is carried out and a detailed description of the behavior of trajectories starting from the interior of the state-space is given. We find that the four monomorphic states are unstable and that a polymorphic state exists which is a global attractor for non-degenerate initial states of the population. The result for the discrete-time replicator coincides with the one of the continuous case.

OC-022 Addressing the interplay between apoptosis and glucose metabolism in liver cirrhosis and HCC

Introduction Pro-inflammatory signalling in the liver promotes the appearance of a metabolic phenotype that involves the transition from mitochondrial respiration to aerobic glycolysis. It was demonstrated that this metabolic shift occurs during the transition from healthy and early stage of liver injury (NAFLD/NASH, ALD to late stage of disease (i.e. cirrhosis), and further escalates during HCC development.1,2This metabolic signature enables dividing cells to satisfy anabolic and energetic needs for biomass production and to suppress apoptotic signalling, which is consistent with increased compensatory hepatic cell proliferation typical of cirrhotic and HCC livers. However other studies in contrast have suggested that hepatocytes are unable to sustain glycolysis during late stage of chronic liver disease.3 Method We used unbiased gene expression analyses of microarray datasets to investigate the expression of glycolytic genes in cirrhotic and HCC livers and correlated their expression with patient outcome. Furthermore, by using a combination of in vitroand in vivoanalyses we have characterised the abilities of a novel anti-apoptotic gene to regulate aerobic glycolysis in liver cirrhosis and HCC. Results mRNA profiling showed significantly higher expression of glycolytic transcripts in cirrhotic and HCC livers compared to normal quiescent livers (P Conclusion In summary, our findings delineate a putative link between aerobic glycolysis and suppression of apoptosis that is an important part of the progression of cirrhosis to HCC. The identification of the mechanism regulating this link may lead to design new therapeutic strategies for human liver disease. This abstract is funded by Foundation for Liver Research Disclosure of interest None Declared. References Beyoglu D, Idle JR. J Hepatol. 2013;59:842–858 Kakazu E, Kondo Y, Kogure T, et al. Plasma amino acids imbalance in cirrhotic patients disturbs the tricarboxylic acid cycle of dendritic cell. Sci. Rep. 2013;3:3459 Nishikawa T, et al. J Hepatol. 2014;60:1203–1211

The Bacterium Frischella perrara Causes Scab Formation in the Gut of its Honeybee Host.

ABSTRACTHoneybees harbor well-defined bacterial communities in their guts. The major members of these communities appear to benefit the host, but little is known about how they interact with the host and specifically how they interface with the host immune system. In the pylorus, a short region between the midgut and hindgut, honeybees frequently exhibit scab-like structures on the epithelial gut surface. These structures are reminiscent of a melanization response of the insect immune system. Despite the wide distribution of this phenotype in honeybee populations, its cause has remained elusive. Here, we show that the presence of a common member of the bee gut microbiota, the gammaproteobacterium Frischella perrara, correlates with the appearance of the scab phenotype. Bacterial colonization precedes scab formation, and F. perrara specifically localizes to the melanized regions of the host epithelium. Under controlled laboratory conditions, we demonstrate that exposure of microbiota-free bees to F. perrara but not to other bacteria results in scab formation. This shows that F. perrara can become established in a spatially restricted niche in the gut and triggers a morphological change of the epithelial surface, potentially due to a host immune response. As an intermittent colonizer, this bacterium holds promise for addressing questions of community invasion in a simple yet relevant model system. Moreover, our results show that gut symbionts of bees engage in differential host interactions that are likely to affect gut homeostasis. Future studies should focus on how these different gut bacteria impact honeybee health.

Cytotoxicity and infiltration of human NK cells in in vivo-like tumor spheroids.

BackgroundThe complex cellular networks within tumors, the cytokine milieu, and tumor immune escape mechanisms affecting infiltration and anti-tumor activity of immune cells are of great interest to understand tumor formation and to decipher novel access points for cancer therapy. However, cellular in vitro assays, which rely on monolayer cultures of mammalian cell lines, neglect the three-dimensional architecture of a tumor, thus limiting their validity for the in vivo situation.MethodsThree-dimensional in vivo-like tumor spheroid were established from human cervical carcinoma cell lines as proof of concept to investigate infiltration and cytotoxicity of NK cells in a 96-well plate format, which is applicable for high-throughput screening. Tumor spheroids were monitored for NK cell infiltration and cytotoxicity by flow cytometry. Infiltrated NK cells, could be recovered by magnetic cell separation.ResultsThe tumor spheroids were stable over several days with minor alterations in phenotypic appearance. The tumor spheroids expressed high levels of cellular ligands for the natural killer (NK) group 2D receptor (NKG2D), mediating spheroid destruction by primary human NK cells. Interestingly, destruction of a three-dimensional tumor spheroid took much longer when compared to the parental monolayer cultures. Moreover, destruction of tumor spheroids was accompanied by infiltration of a fraction of NK cells, which could be recovered at high purity.ConclusionTumor spheroids represent a versatile in vivo-like model system to study cytotoxicity and infiltration of immune cells in high-throughput screening. This system might proof useful for the investigation of the modulatory potential of soluble factors and cells of the tumor microenvironment on immune cell activity as well as profiling of patient-/donor-derived immune cells to personalize cellular immunotherapy.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1321-y) contains supplementary material, which is available to authorized users.

Pseudohypoparathyroidism: phenotypic spectrum in kindred

Pseudohypoparathyroidism (PHP) encompasses a heterogeneous group of disorders due to an inactivating mutation in the GNAS gene which encodes the α subunit of Gs proteins (Gsα). Gsα plays a crucial role in intracellular signal transduction of peptides, hormones and neurotransmitter receptors in multiple tissues. Key features of PHP include Albright Hereditary Osteodystrophy (AHO) and biochemical evidence of multiple hormone resistances. There are several conflicting mechanisms for its heterogeneity; a possible explanation is a tissue-specific differential imprinting of Gsα protein. PHP type1a has AHO with multiple hormone resistance and is inherited as maternal imprinting defect. PHP type 1b presents with hormone resistance but no AHO features and is probably due to epigenetic methylation defects. Peudopseudohypoparathyroidism is another subtype with AHO but absence of hormone resistance and is inherited as paternal inactivating mutation. We describe a family with female members having PHP with variable clinical and biochemical features. Two female siblings from non-consanguineous parents, patient A (15 year) & patient B (13 year) presented at birth with raised TSH levels and were diagnosed to have congenital hypothyroidism and treated with thyroxine replacement. Patient A was noted to have infantile obesity with short stature and evolving phenotypic features consistent with AHO. Further history revealed that her sister patient B has similar phenotypic appearance and was confirmed on clinical exam. Biochemical evaluation for Patient A showed a borderline low calcium and normal phosphate level with elevated PTH while Patient B had normal calcium and phosphate levels with high PTH. Both patients entered puberty at 11 years and patient A progressed to breast tanner 4 but has no menarche at 15 years despite pubertal gonadotropin levels (Table ​(Table1),1), advanced bone age (18 years) & mature uterus. Patient B is currently 12.5 years old and has progressed to tanner 3 breasts with no menarche. Mother exhibits features of AHO without hormone resistance. The father and younger brother do not have any features of AHO. Table 1 The two patients with PHP described above had an interesting presentation as congenital hypothyroidism with features of AHO evolving later in life. They exhibit clinical evidence of maternal transmission with end-organ resistance. This family illustrates heterogeneity of presentation of GNAS mutation. Written informed consent was obtained from the patients for publication of this abstract. A copy of the written consent is available for review by the Editor of this journal.