Phenotypical Evidence Research Articles

Morpho-Anatomical Degeneration of Dopaminergic Neurons in Adult Zebrafish Brain after Exposure to Nickel

Chronic exposure to heavy metals has been widely demonstrated to induce pathological features in different tissues and, in particular, in the central nervous system. Specific neurons, including dopaminergic neurons, were observed to be more susceptible to toxic agents. Several previous studies performed on zebrafish (Danio rerio) models observed that exposure to nickel (one of the most abundant heavy metals) induces impairment of memory and anxious-like behaviors. Nevertheless, this phenotypical evidence has not been associated with dopaminergic system damage, and no reports showing the effects of nickel on dopaminergic neurons are available. In this study, we aim to analyze the precise distribution and variation in dopaminergic neurons in adult zebrafish after chronic (96 h) exposure to nickel ions dissolved in water at different sub-lethal doses (0.4 mg L−1; 2 mg L−1 and 4 mg L−1). The effects of treatment on dopaminergic neurons were evaluated by measuring transcript and protein levels of tyrosine hydroxylase (TH), described as a dopaminergic neuron marker. As shown, the expression of the th1 and th2 genes was reduced in the entire brain of zebrafish treated with nickel. Immunostaining analysis allowed us to localize TH-expressing neurons mainly in the posterior tuberculum, where they were observed to be reduced after nickel treatment in a dose-dependent fashion. Consistently, the TUNEL assay revealed a significant increase in apoptosis of TH-expressing cells after treatment with 2 mg L−1 and 4 mg L−1 of nickel. Our findings represent the first evidence of the effect of nickel on the dopaminergic system.

Approach strategies and application of metabolomics to biotechnology in plants.

Metabolomics refers to the technology for the comprehensive analysis of metabolites and low-molecular-weight compounds in a biological system, such as cells or tissues. Metabolites play an important role in biological phenomena through their direct involvement in the regulation of physiological mechanisms, such as maintaining cell homeostasis or signal transmission through protein-protein interactions. The current review aims provide a framework for how the integrated analysis of metabolites, their functional actions and inherent biological information can be used to understand biological phenomena related to the regulation of metabolites and how this information can be applied to safety assessments of crops created using biotechnology. Advancement in technology and analytical instrumentation have led new ways to examine the convergence between biology and chemistry, which has yielded a deeper understanding of complex biological phenomena. Metabolomics can be utilized and applied to safety assessments of biotechnology products through a systematic approach using metabolite-level data processing algorithms, statistical techniques, and database development. The integration of metabolomics data with sequencing data is a key step towards improving additional phenotypical evidence to elucidate the degree of environmental affects for variants found in genome associated with metabolic processes. Moreover, information analysis technology such as big data, machine learning, and IT investment must be introduced to establish a system for data extraction, selection, and metabolomic data analysis for the interpretation of biological implications of biotechnology innovations. This review outlines the integrity of metabolomics assessments in determining the consequences of genetic engineering and biotechnology in plants.

Evidence of mitochondria origin of SARS-CoV-2 double-membrane vesicles: a review.

Coronavirus Disease-19 (COVID-19) pandemic is caused by SARS-CoV-2 that has infected more than 600 million people and killed more than 6 million people worldwide. This infection affects mainly certain groups of people that have high susceptibility to present severe COVID-19 due to comorbidities. Moreover, the long-COVID-19 comprises a series of symptoms that may remain in some patients for months after infection that further compromises their health. Thus, since this pandemic is profoundly affecting health, economy, and social life of societies, a deeper understanding of viral replication cycle could help to envisage novel therapeutic alternatives that limit or stop COVID-19. Several findings have unexpectedly discovered that mitochondria play a critical role in SARS-CoV-2 cell infection. Indeed, it has been suggested that this organelle could be the origin of its replication niches, the double membrane vesicles (DMV). In this regard, mitochondria derived vesicles (MDV), involved in mitochondria quality control, discovered almost 15 years ago, comprise a subpopulation characterized by a double membrane. MDV shedding is induced by mitochondrial stress, and it has a fast assembly dynamic, reason that perhaps has precluded their identification in electron microscopy or tomography studies. These and other features of MDV together with recent SARS-CoV-2 protein interactome and other findings link SARS-CoV-2 to mitochondria and support that these vesicles are the precursors of SARS-CoV-2 induced DMV. In this work, the morphological, biochemical, molecular, and cellular evidence that supports this hypothesis is reviewed and integrated into the current model of SARS-CoV-2 cell infection. In this scheme, some relevant questions are raised as pending topics for research that would help in the near future to test this hypothesis. The intention of this work is to provide a novel framework that could open new possibilities to tackle SARS-CoV-2 pandemic through mitochondria and DMV targeted therapies.

Genome-based Reclassification of Paraburkholderia insulsa as a Later Heterotypic Synonym of Paraburkholderia fungorum and Proposal of Paraburkholderia terrae subsp. terrae subsp. nov. and Paraburkholderia terrae subsp. steynii subsp. nov.

Based on the 16S rRNA gene sequences similarity of > 99.8%, the phylogeny of 88 Paraburkholderia strains was reconstructed. Further, they were subjected to overall genome-related indices (OGRI), which resulted in the identification of distinct pairs of species that were closely related. A pair consist of the type strains of Paraburkholderia insulsa and Paraburkholderia fungorum possessed a dDDH value of 87.9%, correspondingly, and the average nucleotide identity (ANI) value was 98.5%. Based on the phylogenetic analysis, OGRI and phenotypical evidence, P. insulsa was proposed as a later heterotypic synonym of P. fungorum. Furthermore, a pair comprising type strains of Paraburkholderia terrae and Paraburkholderia steynii possessed dDDH and ANI values of 71.2% and 96.6%, respectively, and difference in phenotypic traits, which supports a subspecies proposal within these taxa. Thus, the recently described Paraburkholderia steynii wasproposed into two subspecies namely Paraburkholderia terrae subsp terrae subsp. nov and as Paraburkholderiaterraesubsp. steynii subsp. nov.

Review of Applications of Near-Infrared Spectroscopy in Two Rare Disorders with Executive and Neurological Dysfunction: UCD and PKU.

Studying rare diseases, particularly those with neurological dysfunction, is a challenge to researchers and healthcare professionals due to their complexity and small population with geographical dispersion. Universal and standardized biomarkers generated by tools such as functional neuroimaging have been forged to collect baseline data as well as treatment effects. However, the cost and heavily infrastructural requirement of those technologies have substantially limited their availability. Thus, developing non-invasive, portable, and inexpensive modalities has become a major focus for both researchers and clinicians. When considering neurological disorders and diseases with executive dysfunction, EEG is the most convenient tool to obtain biomarkers which can correlate the objective severity and clinical observation of these conditions. However, studies have also shown that EEG biomarkers and clinical observations alone are not sensitive enough since not all the patients present classical phenotypical features or EEG evidence of dysfunction. This article reviews disorders, including two rare disorders with neurological dysfunction and the usefulness of functional near-infrared spectroscopy (fNIRS) as a non-invasive optical modality to obtain hemodynamic biomarkers of diseases and for screening and monitoring the disease.

Risk of Metachronous Colorectal Cancer in Lynch Syndrome: Who Needs an Extended Resection?

Lynch syndrome (LS) is the most common genetic condition associated with early-onset colorectal cancer. It is inherited in an autosomal dominant fashion. The increased cancer risk is due to a germline mutation in one of the mismatch repair (MMR) genes (MLH1, MSH2, MSH6, and PMS2) or the EPCAM gene. This leads to a deficient DNA mismatch repair mechanism, resulting in the accumulation of nucleotide changes and microsatellite instability, providing phenotypical evidence that MMR is not functioning normally. LS is associated with a high risk of early-onset colorectal cancer and recurrence. Thus, when undergoing surgery for primary colorectal cancer, extended resection should be discussed with the patient. This review provides an overview of current surgical risk-reducing strategies in LS-associated colorectal cancer. Surgical treatment for LS carriers with colorectal cancer needs to be highly individualized, based on patient and disease characteristics. Strategies are presented to guide decision making in pathologic MMR gene mutation carriers undergoing surgery for colorectal cancer.

Integration of metabolomics with genomics: Metabolic gene prioritization using metabolomics data and genomic variant (CADD) scores.

The integration of metabolomics data with sequencing data is a key step towards improving the diagnostic process for finding the disease-causing genetic variant(s) in patients suspected of having an inborn error of metabolism (IEM). The measured metabolite levels could provide additional phenotypical evidence to elucidate the degree of pathogenicity for variants found in genes associated with metabolic processes. We present a computational approach, called Reafect, that calculates for each reaction in a metabolic pathway a score indicating whether that reaction is deficient or not. When calculating this score, Reafect takes multiple factors into account: the magnitude and sign of alterations in the metabolite levels, the reaction distances between metabolites and reactions in the pathway, and the biochemical directionality of the reactions. We applied Reafect to untargeted metabolomics data of 72 patient samples with a known IEM and found that in 81% of the cases the correct deficient enzyme was ranked within the top 5% of all considered enzyme deficiencies. Next, we integrated Reafect with Combined Annotation Dependent Depletion (CADD) scores (a measure for gene variant deleteriousness) and ranked the metabolic genes of 27 IEM patients. We observed that this integrated approach significantly improved the prioritization of the genes containing the disease-causing variant when compared with the two approaches individually. For 15/27 IEM patients the correct affected gene was ranked within the top 0.25% of the set of potentially affected genes. Together, our findings suggest that metabolomics data improves the identification of affected genes in patients suffering from IEM.

First reproductive signs of inbreeding depression in Southern California male mountain lions (Puma concolor)

Long-term studies of mountain lions (Puma concolor) in Southern California have documented persistent small population sizes and the lowest genetic variation of any mountain lion population, except for the Federally endangered mountain lion subspecies, the Florida panther (Puma concolor coryi). There is overwhelming molecular evidence supporting inbreeding and low genetic diversity in these Southern California populations but there is a lack of phenotypical evidence of inbreeding depression. The primary goal of this study was to assess male mountain lions, in Southern California, for teratospermia (>60% abnormal sperm production), one of the first signs of inbreeding depression in mountain lions that are associated with decreased reproduction and population decline. From December 2019 to December 2020, we surveyed mountain lions during live captures, after mortality events, and in images collected from camera traps in the following populations: Santa Monica Mountains, Santa Susana Mountains, Santa Ana Mountains, and the Eastern Peninsular Range. Mountain lions were sampled for known physical abnormalities associated with inbreeding depression such as teratospermia, cryptorchidism, and distal tail kinks. For teratospermia, we extracted testes from five males post-mortem to assess sperm morphology. Epididymal sperm evaluations revealed all males were teratospermic. Across all samples, on average, 93% of observed spermatozoa were abnormal. We physically examined 32 mountain lions (males and females) for distal tail kinks, and we observed one individual affected. We examined 15 male mountain lions for cryptorchidism, and we observed one unilaterally cryptorchid male and one male with testes that differed significantly in size, likely reflecting asynchronous migration of the testes during puberty. Further, we identified three other animals in camera-trap images that had distal tail kinks, for a total of four. In conclusion, from December 2019 to December 2020, we identified nine individuals exhibiting physical signs of inbreeding depression. These reproductive and physical signs of inbreeding depression in Southern California mountain lions increase the urgency of conservation efforts in the region.

Evidence of mitochondria origin of SARS-CoV-2 double-membrane vesicles: a review.

Coronavirus Disease-19 (COVID-19) pandemic is caused by the coronavirus SARS-CoV-2 that has infected in a year more than 200 million people and has killed almost 4.5 million people worldwide. This infection affects mainly certain groups of people that have high susceptibility to present severe COVID-19 due to comorbidities. Moreover, the long-COVID-19 comprises a series of symptoms that may remain in some patients for months after infection that further compromises health of individuals. Therefore, this pandemic poses a serious emergency worldwide. Thus, since this pandemic is profoundly affecting economic and social life of societies, a deeper understanding of SARS-CoV-2 infection cycle could help to envisage novel therapeutic alternatives that limit or stop COVID-19. Several recent findings have unexpectedly found that mitochondria play a critical role in SARS-CoV-2 cell infection. Indeed, it has been suggested that this organelle could be the origin of its replication niches, the double membrane vesicles (DMV), as its been observed with another virus. In this regard, mitochondria derived vesicles (MDV), involved in mitochondria quality control, were discovered more than 10 years ago and interestingly there is a population characterized by a double membrane. MDV shedding is induced by mitochondrial stress and it has a fast assembly dynamic, reason that perhaps has precluded their identification in electron microscopy or tomography studies. These and other features of MDV together with recent SARS-CoV-2 protein interactome with the host and other findings linking SARS-CoV-2 to mitochondria, support that these vesicles are the precursors of SARS-CoV-2 induced DMV. In this work, the celular, molecular, phenotypical and biochemical evidence that supports this hypothesis is reviewed and integrated into the current model of SARS-CoV-2 cell infection. In this scheme, some relevant questions are raised as pending topics for research that would help in the near future to test this hypothesis. The intention (abstract truncated).

Phenotypical evidence of effective amelioration of ammonium-inhibited plant (root) growth by exogenous low urea

Ammonium and nitrate are major soil inorganic-nitrogen sources for plant growth, but many species cultivated with even low millimolar NH4+ as a sole N form display a growth retardation. To date, critical biological components and applicable approaches involved in the effective enhancement of NH4+ tolerance remain to be thoroughly explored. Here, we report phenotypical traits of urea-dependent improvement of NH4+-suppressed plant/root growth. Urea at 0.1 mM was sufficient to remarkably stimulate NH4+ (3 mM)-fed cotton growth, showing a 2.5∼4-fold increase in shoot- and root-biomass and total root-length, 20 % higher GS activity, 18 % less NH4+-accumulation in roots, and a comparable plant total-N content compared to the control, implying a novel role for urea in cotton NH4+detoxification. A similar phenomenon was observed in tobacco and rice. Moreover, comparisons between twelve NH4+-grown Arabidopsis accessions revealed a great degree of natural variation in their root-growth response to low urea, with WAR and Blh-1 exhibiting the most significant increase in primary- and lateral-root length and numbers, and Sav-0 and Edi-0 being the most insensitive. Such phenotypical evidence suggests a common ability of plants to accommodate NH4+-stress by responding to exogenous urea, providing a novel aspect for further understanding the process of urea-dependent plant NH4+ tolerance.

UBC-Nepal expedition: phenotypical evidence for evolutionary adaptation in the control of cerebral blood flow and oxygen delivery at high altitude.

Sherpa have lived in the Nepal Himalaya for 25-40 thousand years and display positive physiological adaptations to hypoxia. Sherpa have previously been demonstrated to suffer less negative cerebral side effects of ascent to extreme altitude, yet little is known as to whether or not they display differential regulation of oxygen delivery to the brain compared to lowland natives. We demonstrate that Sherpa have lower brain blood flow during ascent to and acclimatization at high altitude compared to lowlanders and that this difference in flow is not attributable to factors such as mean arterial pressure, blood viscosity and pH. The observed lower cerebral oxygen delivery in Sherpa likely represents a positive adaptation that may indicate a cerebral hypometabolic conservation of energy at altitude and/or decreased risk of other cerebral consequences such as vasogenic oedema. Debilitating side effects of hypoxia manifest within the central nervous system; however, high-altitude natives of the Tibetan plateau, the Sherpa, experience negligible cerebral effects compared to lowland natives at extreme altitude. Phenotypical optimization of the oxygen cascade has been demonstrated in the systemic circulation of Tibetans and Sherpa, likely underscoring their adapted capacity to thrive at altitude. Yet, little is known as to how the cerebral circulation of Sherpa may be adapted. To examine potential differences in cerebral oxygen delivery in Sherpa compared to lowlanders we measured arterial blood gases and global cerebral blood flow (duplex ultrasound) during a 9day ascent to 5050m. Although cerebral oxygen delivery was maintained during ascent in lowlanders, it was significantly reduced in the Sherpa at 3400m (-30.3±21.6%; P<0.01) and 4371m (-14.2±10.7%; P=0.03). Furthermore, linear mixed effects modelling indicated that independent of differences in mean arterial pressure, pH and blood viscosity, race accounts for an approximately 100mLmin-1 (∼17-34%) lower cerebral blood flow in Sherpa compared to lowlanders across ascent to altitude (P=0.046). To ascertain the role of chronic hypoxia independent of the ascent, Sherpa who had not recently descended were also examined at 5050m. In these Sherpa, cerebral oxygen delivery was also lower compared to lowlanders (∼22% lower; P<0.01). We highlight new information about the influence of race and genetic adaptation in the regulation of cerebral oxygen delivery. The lower cerebral oxygen delivery in the Sherpa potentially represents a positive adaptation considering Sherpa endure less deleterious cerebral consequences than lowlanders at altitude.

Recognising Selves in Others: Situating Dougla Manoeuvrability as Shared Mixed-Race Ontology

ABSTRACTIn this paper, which is part of a larger qualitative study, we contemplate how mixed race selves are recognised and recognise others. Through our interrogation of the dougla, a distinct Caribbean mixed race identity, the product of contact between peoples brought to the Caribbean to build plantation economies in colonial societies, particularly former freed African slave labour and newly imported Indian indentured labour, we assert that mixedness is a shared ontology, made recognisable by not only genotypical and phenotypical evidence, but by the distinct experience of occupying spaces of ambiguity, ambivalence and/or inbetweeness. We argue the ontological experience of inbetweeness and the act of recognising selves in others rests in the active management of selves invoked by this state of being, what we conceptualise as manoeuvrability. Manoeuvrability, which takes the consideration of shared experiences of mixedness beyond static states to the dynamic engagement with self and other, facilitates in its dynamism the plausible mutual recognition that we suggest allows for speaking across differences.

Euphorbia Section Hainanensis (Euphorbiaceae), a New Section Endemic to the Hainan Island of China From Biogeographical, Karyological, and Phenotypical Evidence.

Euphorbia hainanensis is an endangered species endemic to the tropical Hainan Island in southern China and of historical importance for Chinese medicine. It is currently the only unplaced species of the genus Euphorbia (Euphorbiaceae) due to its isolated island distribution and debated placement by a previous molecular phylogenetic study. We sequenced nuclear ITS and chloroplast rbcL and ndhF for newly collected accessions of E. hainanensis and additional Euphorbia species found in Hainan, and analyzed the sequences in the context of the entire genus together with published data. All gene regions highly supported that E. hainanensis occupied an isolated phylogenetic position, showing no close affinity with any known Euphorbia sections suggesting it was a new section. ITS placed E. hainanensis sister to sect. Crossadenia (subgenus Chamaesyce) from Brazil with an estimated divergence time of 9.3-30.6 Mya while the chloroplast markers placed E. hainanensis at a position sister to the entire New World clade of Euphorbia subgenus Chamaesyce. In addition, our karyological results suggested a close affinity between E. hainanensis and the New World species of Euphorbia subg. Chamaesyce, with which shared the same chromosome number 2n = 28 and basic chromosome number x = 7. Phenotypically, E. hainanensis is unique with no close resemblance to other species in Euphorbia subg. Chamaesyce. Based on its isolated biogeographical, karyological, and phenotypical position, we propose a new section E. subgenus Chamaesyce section Hainanensis that might origin from long distance dispersal events because collective evidences showed a close affinity between the species from the Old World with those from the New World.

A new pelvic-less species of Melanorivulus Costa (Cyprinodontiformes: Cynolebiidae), with a discussion on the pelvic-fin absence in killifishes

Melanorivulus nelsoni, new species, is described from a stream draining into the upper rio Paraguai basin, in the municipality of Juscimeira, State of Mato Grosso, Brazil. It is distinguished from all other congeners, except M. pictus (Costa) and M. planaltinus (Costa &amp; Brasil), by the lack of the pelvic fin and girdle (although only in M. nelsoni they are invariably absent). Furthermore, M. nelsoni is distinguished from all other congeners, except M. pindorama, M. pinima and M. rutilicaudus, by having 10 transverse series of scales. Additional characters are provided to distinguish M. nelsoni from these and other congeners. The analysis of a large number of M. pictus specimens showed that this species occasionally exhibits a single or no pelvic fins. We found phenotypical evidence that the absence of pelvic fins in Melanorivulus species is likely genetically controlled by an allele that, when in heterozygosity, may result in unpredictable phenotypes. Data gathered from literature, along with our own results, suggest that the Cyprinodontiformes, especially the Cynolebiidae and the Cyprinodontidae, have a particularly high probability of evolving absence of pelvic fins, which is usually associated with body elongation. We suggest that in the case of Cyprinodontiformes this evolutionary trend might be related to the shape and position of the vertical fins.

Comparative genomics and genome biology of invasive Campylobacter jejuni.

Campylobacter jejuni is a major pathogen in bacterial gastroenteritis worldwide and can cause bacteremia in severe cases. C. jejuni is highly structured into clonal lineages of which the ST677CC lineage has been overrepresented among C. jejuni isolates derived from blood. In this study, we characterized the genomes of 31 C. jejuni blood isolates and 24 faecal isolates belonging to ST677CC in order to study the genome biology related to C. jejuni invasiveness. We combined the genome analyses with phenotypical evidence on serum resistance which was associated with phase variation of wcbK; a GDP-mannose 4,6-dehydratase involved in capsular biosynthesis. We also describe the finding of a Type III restriction-modification system unique to the ST-794 sublineage. However, features previously considered to be related to pathogenesis of C. jejuni were either absent or disrupted among our strains. Our results refine the role of capsule features associated with invasive disease and accentuate the possibility of methylation and restriction enzymes in the potential of C. jejuni to establish invasive infections. Our findings underline the importance of studying clinically relevant well-characterized bacterial strains in order to understand pathogenesis mechanisms important in human infections.

Development of a Murine Model for CMV‐Induced Hearing Loss

Objective: 1) Illustrate phenotypical evidence of sensorineural hearing loss by showing elevation of auditory evoked brainstem response (ABR) thresholds and diminished distortion product otoacoustic emission (DPOAE) in newborn mice inoculated with murine cytomegalovirus (mCMV). 2) Demonstrate evidence of mCMV-mediated pathology based on microscopic examination of infected cochleas. Method: BALB/c mice were injected at postnatal day 3 with 100 pfu of mCMV; controls received saline. Hearing thresholds were assessed using DPOAE and ABR at 4 weeks of age and onward. Histologic changes in temporal bones were compared between infected and control mice. Results: More than 50% of infected mice had significantly higher DPOAE and ABR thresholds at 4 weeks of age as compared to age-matched controls ( P &lt; .008). Five mice (45%) had profound hearing loss (≥80 dB) at 4 weeks of age; 7 mice (50%) progressed to profound hearing loss at 6 weeks. 40% of mice had asymmetric hearing loss. Temporal bone histology showed diffuse loss of outer hair cells in profoundly deaf mice as compared to controls. Conclusion: Intracerebral injection of mCMV to newborn mice can cause hearing loss with high to low frequency ABR progression, and diminished DPOAE. This hearing loss is asymmetric and progressive, similar to human infection. Histologic examination shows loss of outer hair cells in mCMV infected mice, suggesting that CMV infection may target the outer hair cells. Further studies using this model should shed light on the mechanism underlying CMV-mediated hearing loss and provide foundation for better managing and treatment of the condition.

Small sets of interacting proteins suggest functional linkage mechanisms via Bayesian analogical reasoning.

Motivation: Proteins and protein complexes coordinate their activity to execute cellular functions. In a number of experimental settings, including synthetic genetic arrays, genetic perturbations and RNAi screens, scientists identify a small set of protein interactions of interest. A working hypothesis is often that these interactions are the observable phenotypes of some functional process, which is not directly observable. Confirmatory analysis requires finding other pairs of proteins whose interaction may be additional phenotypical evidence about the same functional process. Extant methods for finding additional protein interactions rely heavily on the information in the newly identified set of interactions. For instance, these methods leverage the attributes of the individual proteins directly, in a supervised setting, in order to find relevant protein pairs. A small set of protein interactions provides a small sample to train parameters of prediction methods, thus leading to low confidence.Results: We develop RBSets, a computational approach to ranking protein interactions rooted in analogical reasoning; that is, the ability to learn and generalize relations between objects. Our approach is tailored to situations where the training set of protein interactions is small, and leverages the attributes of the individual proteins indirectly, in a Bayesian ranking setting that is perhaps closest to propensity scoring in mathematical psychology. We find that RBSets leads to good performance in identifying additional interactions starting from a small evidence set of interacting proteins, for which an underlying biological logic in terms of functional processes and signaling pathways can be established with some confidence. Our approach is scalable and can be applied to large databases with minimal computational overhead. Our results suggest that analogical reasoning within a Bayesian ranking problem is a promising new approach for real-time biological discovery.Availability: Java code is available at: www.gatsby.ucl.ac.uk/~rbas.Contact: airoldi@fas.harvard.edu; kheller@mit.edu; ricardo@stats.ucl.ac.uk

Structural and Functional Peculiarities of Mast Cells in Undifferentiated Connective Tissue Dysplasia

We performed an immunomorphological study of mast cells from undamaged skin in women with phenotypical evidence of undifferentiated connective tissue dysplasia syndrome, patients of cosmetological clinics. It was found that the numerical density of mast cells containing chymase granules in this condition 1.7-fold surpassed the corresponding parameter in patients without signs of connective tissue dysplasia syndrome, which probably was a result of compensatory and adaptive reaction aimed at activation of the synthesis of the connective tissue extracellular matrix components. It was hypothesized that increased content of chymase-positive mast cells in the skin of patients with connective tissue dysplasia syndrome contributed to the formation of associated arterial hypertension.

Potential role of the steroid receptor pattern in the response of inoperable intra-abdominal desmoid to toremifene after failure of tamoxifen therapy

Dear Editor: Desmoid tumors are rare, non-metastatic soft tissue tumors caused by an abnormal clonal proliferation of fibroblastlike cells with a huge amount of extracellular matrix. Although they can occur sporadically, particularly in the extremities, they typically develop in about 20% of patients with a family history of adenomatous polyposis, in this case, Gardner's syndrome. Desmoid tumors are, in fact, the first cause of death in patients submitted to total proctocolectomy for familial adenomatous polyposis because despite their benign nature, their uncontrolled intra-abdominal growth with mesenteric infiltration usually makes surgical removal impossible. Multiorgan transplantation is usually the final lifesaving option, although the high peri-operative mortality and the risk of further recurrence of the desmoids are grave drawbacks. If feasible, surgical removal is still the most common approach, although the high reported rate of recurrence, up to 30–40%, should discourage this option in favor of other, more conservative treatments. However, this type of tumor usually responds poorly to traditional adjuvant therapy, including radiotherapy and chemotherapy, probably because of the low cellular density. Several other treatments based on non-steroidal antiinflammatory drugs, interferon, imatinib, radio-, and chemotherapy have all been tried with variable success. Recently, increasing attention has been paid to the effect of different anti-estrogen therapies on desmoids, even if the estrogen receptors (ERα and Erβ) issue is controversial. A 32-year-old Caucasian woman underwent total colectomy and ileorectal anastomosis for diffuse colonic polyposis in 1998. The rectum was spared because the polyps, although large, were few and endoscopically removed and in view of the young age of the patient and her desire for future maternity. Histology of the resected specimen revealed multiple adenomatous polyps, some with early cancer foci invading the submucosa. Her family history included several cases with phenotypical evidence of familiar adenomatous polyposis (FAP). Her father died of cancer of the sigmoid colon; one of her sisters died of cerebellar cancer at the age of 8 years (Turcot's syndrome), and another sister was diagnosed with a Gardner's variant of FAP, featuring non-resectable intraabdominal desmoids, at the age of 38 years, and treated with bowel transplantation in 1999. The outcome was very poor, featuring several other operations for desmoids recurrence and death 1 year later. Two other members of the same family (paternal uncles) also died of colonic cancer. Genetic testing revealed a deletion of 5 bp in position 3183 in the APC gene in most of the members of this family, including our patient. One year after the endoscopic removal of the polyps, an abdominal computerized tomography (CT) scan revealed a solid mass in her right iliac fossa measuring 8.5 cm in diameter. Another smaller mass, measuring 6.5 cm, was evident medially, with the same characteristics. Three months There are no sources of support for this article.

The role of complement in the adherence of microbubbles to dysfunctional arterial endothelium and atherosclerotic plaque

To determine whether serum complement C3 mediates adherence of albumin-encapsulated microbubbles to vascular endothelium in the development of atherosclerotic plaques. Adherence of microbubbles to aortic endothelium was examined with scanning electron microscopy following intravenous injection of 20% intralipid in wild-type mice, genetic complement-deficient mice (C3-/-), and in pharmacologic C3-depleted wild-type mice. In a second experimental model, atherosclerostic plaque was induced in apolipoprotein E-deficient mice (apoE-/-), and adherence of microbubbles to atherosclerotic plaques was evaluated using fluorescent microscopy of fluorescein isothiocynate-conjugated microbubbles. Finally, imaging of aortas was performed in eight rats (four JCR:LA-cp atherosclerosis-prone rats on high cholesterol diets; four controls) following intravenous albumin microbubble injections (PESDA) to determine whether microbubble adherence to the endothelium could be detected with low mechanical index pulse sequence schemes. Scanning electron microscopy confirmed the adherence of microbubbles to the endothelial cells of the aorta in wild-type mice following induction of hypertriglyceridemia but not in C3-depleted mice. Microbubble adherence to the endothelial surface of atherosclerotic plaque was confirmed in all apoE-/- mice (median 172 microbubbles/field; compared to a median of 3 microbubbles/field in cobra venom factor-treated apoE-/- mice; p < 0.001). Low mechanical index ultrasound imaging detected microbubble adherence in all JCR atherosclerosis prone rats even in the absence of vasomotor or phenotypical evidence of endothelial dysfunction. The numbers of adherent microbubbles correlated with serum triglyceride levels, and were seen in conjunction with increased endothelial nitric oxide synthase activity. Complement C3 binds to albumin-encapsulated microbubbles and mediates microbubble adherence to vascular endothelium both early and late in the atherosclerotic process.