19 research outputs found
Ten-year experience of more than 35,000 orofacial clefts in Africa
Abstract
Background
Surgical correction of orofacial clefts greatly mitigates negative outcomes. However, access to reconstructive surgery is limited in developing countries. The present study reviews epidemiological data from a single charitable organization, Smile Train, with a database of surgical cases from 33 African countries from 2001–2011.
Methods
Demographic and clinical patient data were collected from questionnaires completed by the participating surgeons. These data were recorded in Excel, analyzed using SPSS and compared with previously reported data.
Results
Questionnaires were completed for 36,384 patients by 389 African surgeons. The distribution of clefts was: 34.44% clefts of the lip (CL), 58.87% clefts of the lip and palate (CLP), and 6.69% clefts of the palate only (CP). The male to female ratio was 1.46:1, and the unilateral: bilateral ratio 2.93:1, with left-sided predominance 1.69:1. Associated anomalies were found in 4.18% of patients. The most frequent surgeries included primary lip/nose repairs, unilateral (68.36%) and bilateral (11.84%). There was seasonal variation in the frequency of oral cleft births with the highest in January and lowest by December. The average age at surgery was 9.34 years and increased in countries with lower gross domestic products. The average hospital stay was 4.5 days. The reported complication rate was 1.92%.
Conclusions
With the exception of cleft palates, results follow trends of worldwide epidemiologic reports of 25% CL, 50% CLP, and 25% CP, 2:1 unilateral:bilateral and left:right ratios, and male predominance. Fewer than expected patients, especially females, presented with isolated cleft palates, suggesting that limitations in economic resources and cultural aesthetics of the obvious lip deformity may outweigh functional concerns and access to treatment for females. A fewer than expected associated anomalies suggests either true ethnic variation, or that more severely-affected patients are not presenting for treatment. The epidemiology of orofacial clefting in Africa has been difficult to assess due to the diversity of the continent and the considerable variation among study designs. The large sample size of the data collected provides a basis for further study of the epidemiology of orofacial clefting in Africa.http://deepblue.lib.umich.edu/bitstream/2027.42/110688/1/12887_2015_Article_328.pd
Single-cell analysis of patient-derived PDAC organoids reveals cell state heterogeneity and a conserved developmental hierarchy
Pancreatic tumors are frequently divided into basal and classical subtypes. Here, the authors use single cell sequencing to investigate organoids derived from pancreatic cancer tissue and find a hierarchy of distinct cell states, and classical and basal cells existing within the same tumor. Pancreatic ductal adenocarcinoma (PDAC) is projected to be the second leading cause of cancer mortality by 2030. Bulk transcriptomic analyses have distinguished 'classical' from 'basal-like' tumors with more aggressive clinical behavior. We derive PDAC organoids from 18 primary tumors and two matched liver metastases, and show that 'classical' and 'basal-like' cells coexist in individual organoids. By single-cell transcriptome analysis of PDAC organoids and primary PDAC, we identify distinct tumor cell states shared across patients, including a cycling progenitor cell state and a differentiated secretory state. Cell states are connected by a differentiation hierarchy, with 'classical' cells concentrated at the endpoint. In an imaging-based drug screen, expression of 'classical' subtype genes correlates with better drug response. Our results thus uncover a functional hierarchy of PDAC cell states linked to transcriptional tumor subtypes, and support the use of PDAC organoids as a clinically relevant model for in vitro studies of tumor heterogeneity
Anisotropic Panglial Coupling Reflects Tonotopic Organization in the Inferior Colliculus
Astrocytes and oligodendrocytes in different brain regions form panglial networks and the topography of such networks can correlate with neuronal topography and function. Astrocyte-oligodendrocyte networks in the lateral superior olive (LSO)—an auditory brainstem nucleus—were found to be anisotropic with a preferred orientation orthogonally to the tonotopic axis. We hypothesized that such a specialization might be present in other tonotopically organized brainstem nuclei, too. Thus, we analyzed gap junctional coupling in the center of the inferior colliculus (IC)—another nucleus of the auditory brainstem that exhibits tonotopic organization. In acute brainstem slices obtained from mice, IC networks were traced employing whole-cell patch-clamp recordings of single sulforhodamine (SR) 101-identified astrocytes and concomitant intracellular loading of the gap junction-permeable tracer neurobiotin. The majority of dye-coupled networks exhibited an oval topography, which was preferentially oriented orthogonal to the tonotopic axis. Astrocyte processes showed preferentially the same orientation indicating a correlation between astrocyte and network topography. In addition to SR101-positive astrocytes, IC networks contained oligodendrocytes. Using Na+ imaging, we analyzed the capability of IC networks to redistribute small ions. Na+ bi-directionally diffused between SR101-positive astrocytes and SR101-negative cells—presumably oligodendrocytes—showing the functionality of IC networks. Taken together, our results demonstrate that IC astrocytes and IC oligodendrocytes form functional anisotropic panglial networks that are preferentially oriented orthogonal to the tonotopic axis. Thus, our data indicate that the topographic specialization of glial networks seen in IC and LSO might be a general feature of tonotopically organized auditory brainstem nuclei
"It's a balance of just getting things right"
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. This study was funded by NHS Grampian. FD, LC, JC, and GMcN receive personal support from the RESAS programme of the Scottish Government Nutrition and Health. We would also like to thank Caroline Comerford of NHS Grampian and other members of the research steering group for their advice during the study; the parents for their time and input; the nursery school staff for distributing study packs for parents; Andrea Gilmartin for organising the focus groups and Dr Sandra Carlisle for the helpful comments on earlier drafts of the manuscript.Peer reviewedPublisher PD
Representations of a Common Culture
The following volume is a compilation of student-produced texts written over the course of a semester-long Q-Team research-based learning class at the Humboldt University of Berlin. The aim of this course was to explore the various understandings and definitions of Yugoslav culture through the prism of its representations found primarily in the archives of the German Foreign Service, compelling the students to design and carry out original research projects in line with their personal academic interests. This exercise has resulted in a series of five co-authored papers treating a multitude of topics addressing the concept of culture in the Yugoslav context, as seen through the eyes of diplomatic staff, based in majoritarily on research conducted in the political archives of the German Foreign Service
Gray matter NG2 cells display multiple Ca2+-signaling pathways and highly motile processes.
NG2 cells, the fourth type of glia in the mammalian CNS, receive synaptic input from neurons. The function of this innervation is unknown yet. Postsynaptic changes in intracellular Ca(2+)-concentration ([Ca(2+)](i)) might be a possible consequence. We employed transgenic mice with fluorescently labeled NG2 cells to address this issue. To identify Ca(2+)-signaling pathways we combined patch-clamp recordings, Ca(2+)-imaging, mRNA-transcript analysis and focal pressure-application of various substances to identified NG2-cells in acute hippocampal slices. We show that activation of voltage-gated Ca(2+)-channels, Ca(2+)-permeable AMPA-receptors, and group I metabotropic glutamate-receptors provoke [Ca(2+)](i)-elevations in NG2 cells. The Ca(2+)-influx is amplified by Ca(2+)-induced Ca(2+)-release. Minimal electrical stimulation of presynaptic neurons caused postsynaptic currents but no somatic [Ca(2+)](i) elevations, suggesting that [Ca(2+)](i) elevations in NG2 cells might be restricted to their processes. Local Ca(2+)-signaling might provoke transmitter release or changes in cell motility. To identify structural prerequisites for such a scenario, we used electron microscopy, immunostaining, mRNA-transcript analysis, and time lapse imaging. We found that NG2 cells form symmetric and asymmetric synapses with presynaptic neurons and show immunoreactivity for vesicular glutamate transporter 1. The processes are actin-based, contain ezrin but not glial filaments, microtubules or endoplasmic reticulum. Furthermore, we demonstrate that NG2 cell processes in situ are highly motile. Our findings demonstrate that gray matter NG2 cells are endowed with the cellular machinery for two-way communication with neighboring cells
Induction of Defense-Related Responses in Cf9 Tomato Cells by the AVR9 Elicitor Peptide of Cladosporium fulvum Is Developmentally Regulated
The AVR9 elicitor from the fungal pathogen Cladosporium fulvum induces defense-related responses, including cell death, specifically in tomato (Lycopersicon esculentum Mill.) plants that carry the Cf-9 resistance gene. To study biochemical mechanisms of resistance in detail, suspension cultures of tomato cells that carry the Cf-9 resistance gene were initiated. Treatment of cells with various elicitors, except AVR9, induced an oxidative burst, ion fluxes, and expression of defense-related genes. Agrobacterium tumefaciens-mediated transformation of Cf9 tomato leaf discs with Avr9-containing constructs resulted efficiently in transgenic callus formation. Although transgenic callus tissue showed normal regeneration capacity, transgenic plants expressing both the Cf-9 and the Avr9 genes were never obtained. Transgenic F(1) seedlings that were generated from crosses between tomato plants expressing the Avr9 gene and wild-type Cf9 plants died within a few weeks. However, callus cultures that were initiated on cotyledons from these seedlings could be maintained for at least 3 months and developed similarly to callus cultures that contained only the Cf-9 or the Avr9 gene. It is concluded, therefore, that induction of defense responses in Cf9 tomato cells by the AVR9 elicitor is developmentally regulated and is absent in callus tissue and cell-suspension cultures, which consists of undifferentiated cells. These results are significant for the use of suspension-cultured cells to investigate signal transduction cascades
Ciliopathy patient variants reveal organelle-specific functions for TUBB4B in axonemal microtubules
Tubulin, one of the most abundant cytoskeletal building blocks, has numerous isotypes in metazoans encoded by different conserved genes. Whether these distinct isotypes form cell type- and context-specific microtubule structures is poorly understood. Based on a cohort of 12 patients with primary ciliary dyskinesia as well as mouse mutants, we identified and characterized variants in the TUBB4B isotype that specifically perturbed centriole and cilium biogenesis. Distinct TUBB4B variants differentially affected microtubule dynamics and cilia formation in a dominant-negative manner. Structure-function studies revealed that different TUBB4B variants disrupted distinct tubulin interfaces, thereby enabling stratification of patients into three classes of ciliopathic diseases. These findings show that specific tubulin isotypes have distinct and nonredundant subcellular functions and establish a link between tubulinopathies and ciliopathies