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Karina Canziani

and 12 more

Background: Manifestations of food allergies vary among patients, being the most common gastrointestinal, skin and respiratory symptoms. This study aimed to identify and characterize polyp Th2 cells as a critical component of the allergic reaction. We previously characterized colorectal polyps in patients sensitized to food allergens as inflammatory, with a Type 2-dominated stroma, with elevated IL-13, IL-4 and locally synthesized IgE. Methods: We isolated milk-specific T cells from tissue and blood of food-sensitized patients (n=10) and obtained cell lines and cell clones. Proliferation, specificity, cytokine secretion, gut homing markers and TCR nature were analyzed after antigen recall; CCL25 was assessed in polyps and surrounding tissue. Results: Lamina propria and peripheral T cells responded similarly to cow´s milk proteins, showing similar cell proliferation index and Th2 cytokine release in vitro. All CD4 + T cells expressed the membrane T αβ receptor and secreted higher IL-13 amounts than unstimulated cells, whereas IFN-γ secretion remained unchanged. Remarkably, the gut homing chemokine receptor CCR9 was augmented in cow’s milk-specific peripheral and lamina propria T cells, and CCL25 was found to be expressed in the inflammatory polyp tissue and not in the adjacent mucosa. Conclusion: We isolated and characterized cow´s milk-specific lamina propria CD4 + TCRαβ + Th2 cells from colonic inflammatory polyps. The CCR9 expression on polyp cells and the increased production of tissue CCL25 might facilitate T cells’ recruitment, which are key players in the allergic reaction to promote local IgE synthesis. Our findings may be critical to proposing rational and novel T cell-targeted immunotherapies.

Norio Yasui-Furukori

and 14 more

The severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), etiological agent of the novel coronavirus disease 2019 (COVID-19), has spread since December 2019, resulting in massive health and economic crisis worldwide. While efforts to stop the pandemic are crucial, collecting epidemiological data to help manage current and future pandemics will be important. In addition to humans, serological and molecular based studies have demonstrated SARS CoV-2 exposure in several wild, domestic and farmed animals. For examples Shriner and the team showed serologically an exposure of 40% to the white deer living in close proximity to urban centers. Additional reports have also emerged of susceptibility of animal’s species like cats, ferrets, raccoon dogs, cynomolgus macaques, rhesus macaques, white-tailed deer, rabbits, Egyptian fruit bats, and Syrian hamsters to SARS-CoV-2 infection.. It’s worth emphasizing that these reports are based on experimental data mostly derived from Europe, USA, South America and parts of Asia. In limited instances natural infections of SARS-CoV-2 have been reported in pet dogs, cats, tigers, lions, snow leopards, pumas, gorillas at zoos and farmed mink and ferrets. The presence of the virus in animal species and an understanding of whether these are natural or recent human to animal transmissions is important. It’s possible that such transmission could passage the virus or subject the virus to a different immunological pressure thereby helping with the development of viral variants in addition to being a host for future reservoirs of the virus. In Kenya SARS-CoV-2 was first detected on March 12 th 2020 from imported human cases of persons who had travelled from the United States. This was followed by detection of imported cases majorly from China, Sweden and United Kingdom. Later infections were confirmed in Nairobi and Mombasa suggesting further cases of disease importations through the major ports of entry. However, no comparable data on animal exposure have hitherto been generated in Kenya. To address this key concern, we focused on three objectives; 1) development of a robust antibody ELISA based on crude SARS-CoV-2 lysate. 2) SARS-CoV-2 serology of domestic animals in Kenya. 3) Corroboration of the crude lysate based seroprevalence data and a commercial ELISA kit based on the Spike receptor binding domain (RBD) antigen. Our sample set included camel sera (both pre- & post outbreak sera), as well as sera from cats and dogs collected at the peak of the pandemic. Our results using the ELISA based on crude SARS-CoV-2 lysate indicated SARS-CoV-2 antibodies in camels (71%, N=145), cats 11% (N=16) and dogs (81%, N=36) with varying titer levels.

Xingjie Tan

and 3 more

Background and purpose: Mutations in the CFTR chloride channel result in intestinal o-structive episodes in cystic fibrosis (CF) patients and in CF animal models. This study explores the possibility of reducing the frequency of obstructive episodes in the Cftr-/- mice by the oral application of a gut selective NHE3 inhibitor tenapanor and searches for the underlying mechanisms involved. Experimental approach: Sex and age-matched Cftr+/+ and Cftr-/- mice were orally gavaged twice daily with 30mgkg-1 tenapanor or vehicle for a period of 21 days. Body weight and stool water content was assessed daily and gastrointestinal transit time (GTT) once weekly. The mice were sacrificed when an intestinal obstruction was suspected or after 21 days, and stool and tissues were collected for further analysis. Key results: 21 day tenapanor application resulted in a significant increase in stool water content, stool alkalinity, and a significant decrease in GTT in Cftr+/+ and Cftr-/- mice. Tenapanor significantly reduced obstructive episodes to 8% compared to 46% in vehicle treated Cftr-/- mice and prevented mucosal inflammation. A decrease in cryptal hyperproliferation, mucus accumulation and mucosal mast cell number was also observed in tenapanor compared to vehicle treated unobstructed Cftr-/- mice. Conclusion and implications: Oral tenapanor application prevented obstructive episodes in CFTR deficient mice and was safe in Cftr+/+ and Cftr-/- mice. These results suggest that tenapanor may be a safe and affordable adjunctive therapy in cystic fibrosis patients to alleviate constipation and prevent recurrent DIOS.

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Yuval Shafir

and 8 more

INTRODUCTION: Transvenous Lead Extraction (TLE) is usually performed via a superior approach. Predictors and outcomes of TLE requiring femoral vein bailout are poorly defined. We aimed to analyze predictors and consequences of TLE requiring femoral bailout. METHODS: A single tertiary center cohort of 421 consecutive patients who underwent TLE between May 2010 and February 2020 were analyzed. Venography was routinely performed before system upgrade to identify occluded veins. Patients were divided into 2 groups according to their need for femoral bailout extraction. RESULTS: A total of 928 leads were extracted with femoral bailout approach was needed in 71 leads(7.7%) among 49 patients(11.6%). A higher proportion of right ventricular(RV) leads required femoral bailout approach compared with right atrial(RA) leads[51/499(10.2%) vs 18/326(5.5%);p=0.02]. Femoral bailout was more common among younger patients, longer lead dwell time, more pocket entries, higher number of extracted leads, presence of abandoned leads and among patients with vascular occlusion. Following multivariate analysis, presence of abandoned leads, vascular occlusion and younger age remained a significant predictor for femoral bailout. Femoral bailout resulted in higher rates of major complications [5/49(10.2%) vs 12/372(3.2%);p=0.05] without intra-procedural mortality and no additional 30-day mortality[2/49(4.1%) vs 33/377(8.8%);p=0.39]. CONCLUSION: TLE of abandoned leads, occluded veins and younger age were found to be predictors of femoral bailout requirement. Despite higher rates of major complications in femoral TLE bailout, mortality was not increased. Venography prior to TLE should be considered for procedure planning.

Manuel E. Izquierdo

and 21 more

Background:  Heterozygote carriers of potentially pathogenic variants in the cystic fibrosis transmembrane conductance regulator ( CFTR) gene have increased asthma risk. However, the frequency and impact of CFTR variation among individuals with asthma is unknown. Objective: To determine whether potentially pathogenic  CFTR variants associate with disease severity and whether individuals with two potentially pathogenic variants exist in a severe asthma-enriched cohort . Methods: We analyzed sequencing data spanning a 190.5Kb region of  CFTR in participants from the Severe Asthma Research Program (SARP1-3). Potentially pathogenic, rare  CFTR variants (frequency<0.05) were classified as CF-causing or of varying clinical consequences (VVCC) ( Regression-based models tested for association between  CFTR genotypes (0-2 potentially pathogenic variants) and severity outcomes. Results: Of 1401 participants, 9.5% (134) had one potentially pathogenic variant, occurring more frequently in non-Hispanic white (NHW, 10.1% [84 of 831]) compared to African American individuals (AA, 5.2% [22 of 426]). We found ≥2 potentially pathogenic  CFTR variants in 1.4% (19); 0.5% (4) of NHW and 2.8% (12) of AA. Potentially pathogenic  CFTR variant genotypes (≥1 or ≥2 variants) were not cumulatively associated with lung function or exacerbations. In NHW, we found three F508del compound heterozygotes with F508del and a VVCC (two 5T;TG12[c.1210-11T>G] and one Arg1070Trp) and a homozygote for the VVCC, 5T;TG12. Conclusions: We found potentially pathogenic  CFTR variants within a severe asthma-enriched cohort , including three compound heterozygote genotypes variably associated with CF in NHW individuals. These findings provide the rationale for  CFTR sequencing and phenotyping of CF-related traits in individuals with severe asthma.

Hanan Al-Abboh

and 2 more

A Novel MECOM Variant Associated with Congenital Amegakaryocytic Thrombocytopenia and Radioulnar Synostosis Hanan Al-Abboh1, Akmal Zahra1 and Adekunle Adekile1,2Pediatric Hematology Unit, Mubarak Hospital1 and Department of Pediatrics, Faculty of Medicine, Kuwait University2, Kuwait Address Correspondence to: Professor Adekunle Adekile Department of Pediatrics Faculty of Medicine Kuwait University PO Box 24923 Safat 13110 Kuwait Email: Tel: +96525319486To the EditorCongenital radioulnar synostosis (RUS) is a rare developmental anomaly of proximal fusion of the radius and ulna, resulting in limited pronation and supination of the forearm. It may accompany other abnormalities in the skeleton, kidney, heart and aneuploidy syndromes1,2. A subset of patients with RUS present with bone marrow failure (BMF) syndromes, characterized by amegakaryocytic thrombocytopenia (RUSAT), progressing to myelodysplasia and pancytopenia2,3. The hematological manifestations are quite variable, with some presenting with severe BMF in childhood, while others are mild and may not present until adulthood.Heterozygous germline variants in the homeobox A11 (HOXA11) gene were the first to be associated with RUS and designated RUSAT14, but lately, several families have been described with variants in the MDS1 and EVI1 complex (MECOM) locus, and referred to as RUSAT22,5,6. Many of these variants appear de novo , while others follow an autosomal dominant inheritance. We, hereby, report the case of a Kuwaiti patient who presented with congenital amegakaryocytic thrombocytopenia (CAMT) in the neonatal period and later noticed to have RUS. Whole exome sequencing revealed a novel MECOM variant.A.A. is a male Kuwaiti, the first child of consanguineous parents and was first seen at the age of 36 days, following antenatal ultrasound diagnosis of bilateral hydronephrosis and right renal cyst. He was a product of induced vaginal delivery with a birth weight of 2.3 kg. After delivery, he was kept under observation in the neonatal intensive care unit. His CBC showed isolated thrombocytopenia (Plt 34 x109/L). He received several platelet transfusions, as well as IVIG twice. Postnatal abdominal ultrasound showed multicystic right kidney, in addition to bilateral hydronephrosis. The mother had no history of thrombocytopenia during pregnancy and there was no other pertinent family history.Physical examination at presentation showed 2 café-au-lait spots, one on the back, measuring 1x2 cm and another over the left leg, that was less than 0.6 cm. There were no obvious dysmorphic features and other systems were unremarkable. CBC showed WBC 11.2 x109/L Hb 10.4 g/dL, MCV 83fl, Plt 49 x109/L, ANC 1.8 x109/L. Renal function tests were normal. Blood film showed no abnormal cells; there was true thrombocytopenia with giant forms. Antiplatelet antibody was negative. Abdominal ultrasound at age 1 month showed complete replacement of the right kidney by cystic changes with left moderate hydronephrosis. Skeletal survey was reportedly normal.Bone marrow biopsy showed normal distribution of granulocytic and erythroid precursors, with severe suppression of megakaryocytosis, consistent with a bone marrow failure syndrome. Chromosomal breakage study was normal. The patient was diagnosed with right undescended testis, as well as right inguinal hernia that were operated at age 1 year and 10 months. At the age 2 and a half years, A.A. was noticed to have limited bilateral arm movement supination and pronation. The mother volunteered that she has a similar defect. X-rays confirmed that the child had bilateral radioulnar synostosis. Whole exome sequencing showed that the patient is heterozygous for a previously-unreported MECOM gene, c.2282A>G mutation. Unfortunately, the parents have not been screened for these mutations.The patient has been under follow up for 4 years, his platelet count has been stable, ranging between 40-50 x109/L, with no bleeding tendency. In spite of his limited arm rotation, he currently functions normally in his daily activities, however, his hand writing skills and ability to engage in sports are yet to be observed since he is still pre-school age. Platelet transfusion is reserved only for severe bleeding, which he has not had. Bone marrow transplant may be considered in future if his bone marrow failure worsens and/or his marrow shows dysplastic changes.Dokal et al3 were the first to report an association between RUS and late-onset BMF, while Thompson et al described its association with CAMT and linked it to the c.872delA ,p.Asn291Thrfs3 variant of the HOXA11gene4,7. More recently, several germline mutations in the MECOM locus have been reported and appear to be the more common cause of RUSAT. Indeed, no other cases of HOXA11 mutations linked to RUSAT have been described since the initial report. Niihori et al8 reported the first 3 heterozygous MECOMmutations in 3 sporadic patients. These variants and those subsequently reported by Walne et al2 are in a highly conserved cluster within 10 amino acids (aa750-760) and impact on either the highly conserved Cys2His2 zinc finger motif (zinc finger 8, aa733-755) or the adjacent linker motif (aa756-760). It has been shown that removal of the 8th zinc finger causes granulopoiesis arrest while mutations and deletions in other parts of the complex, outside the 8th and 9th fingers, are associated with hematological disorders without RUS9.MECOM codes for a zinc finger transcription factor with important roles in normal development and oncogenesis and is involved in the regulation of embryonic development and hematopoietic stem-cell renewal. Hence the phenotype in individuals with these mutations is very variable ranging from BMF to different skeletal, cardiac, renal malformations, B cell deficiency and sensorineural deafness.Our patient showed a previously unreported variant in the region of the 8th zinc finger of the MECOM locus. This c.2282A>G missense variant results in the tyrosine to cysteine substitution at codon 761 (p.Tyr761Cys). The amino acid is in the Zinc finger, C2H2 and Zinc finger, C2H2-like protein domains and is highly evolutionarily conserved. Unfortunately, the parents were not screened for the mutation, however, the mother shows RUS, with normal blood counts. This is consistent with the marked variability in the clinical phenotype. The father is also physically and hematologically normal.Apart from thrombocytopenia, our patient also had renal abnormalities – hydronephrosis and multicystic kidney disease. The natural history of his condition is that he may develop pancytopenia and/or myelodysplasia in the future. He is under close follow up and will be considered for bone marrow transplantation if his condition worsens. In the meantime, he remains hypomegakaryocytic with a platelet count at 30 – 50 x 109/l while other blood cellular elements are normal. His renal function and hearing are being monitored, but still remain normal.AcknowledgementsWe thank the patient’s family for allowing us to report this case. The whole exome sequencing was done at the Laboratory of Genetics and Genomics, Cincinnati Children’s Hospital, Cincinnati, Ohio.References1. Rizzo R, Pavone V, Corsello G, Sorge G, Neri G, Opitz JM. Autosomal dominant and sporadic radio-ulnar synostosis. Am J Med Genet.1997;68(2):127-134.2. Walne A, Tummala H, Ellison A, et al. Expanding the phenotypic and genetic spectrum of radioulnar synostosis associated hematological disease. Haematologica. 2018;103(7):e284-e287.3. Dokal I, Ganly P, Riebero I, et al. Late onset bone marrow failure associated with proximal fusion of radius and ulna: a new syndrome.Br J Haematol. 1989;71(2):277-280.4. Thompson AA, Nguyen LT. Amegakaryocytic thrombocytopenia and radio-ulnar synostosis are associated with HOXA11 mutation. Nat Genet. 2000;26(4):397-398.5. Germeshausen M, Ancliff P, Estrada J, et al. MECOM-associated syndrome: a heterogeneous inherited bone marrow failure syndrome with amegakaryocytic thrombocytopenia. Blood Adv. 2018;2(6):586-596.6. Ripperger T, Hofmann W, Koch JC, et al. MDS1 and EVI1 complex locus (MECOM): a novel candidate gene for hereditary hematological malignancies. Haematologica. 2018;103(2):e55-e58.7. Thompson AA, Woodruff K, Feig SA, Nguyen LT, Schanen NC. Congenital thrombocytopenia and radio-ulnar synostosis: a new familial syndrome.Br J Haematol. 2001;113(4):866-870.8. Niihori T, Ouchi-Uchiyama M, Sasahara Y, et al. Mutations in MECOM, Encoding Oncoprotein EVI1, Cause Radioulnar Synostosis with Amegakaryocytic Thrombocytopenia. Am J Hum Genet.2015;97(6):848-854.9. Nielsen M, Vermont CL, Aten E, et al. Deletion of the 3q26 region including the EVI1 and MDS1 genes in a neonate with congenital thrombocytopenia and subsequent aplastic anaemia. J Med Genet.2012;49(9):598-600.

Hoda Abdelgawad

and 2 more

57-years old man presented with exertional dyspnea. An early systolic murmur was heard over the aortic areas 2D and 3D Echocardiography revealed unicuspid , unicommissural aortic valve (UAV) with a characteristic “teardrop” lateral orifice (Figure A) and moderate valve stenosis (3D planimetered aortic valve area (AVA) is 1.1cm2) (Figure B) Continuous wave Doppler across aortic valve (AV) showed high peak and mean systolic gradients of 85 and 60mmHg respectively.(Figure C). 2D /3D Transesophageal Echocardiography (TOE) revealed a subaortic ridge attached to the posterior annulus (Arrow) (Figure D) Further En-face viewing of the aortic valve from the left ventricular outflow tract (LVOT) perspective showed a shelf-like ridge extending from the commissure to the cusp (Arrow) (Figure E) Zoomed mode of the aortic- LVOT junction confirmed the presence of the subaortic ridge seen attached to the posterior aortic annulus near the commissural opening (Figure F) The patient was referred for surgical consultation .. Unicupid aortic valve (UAV) is a rare congenital anomaly that has.2 subtypes ; unicomissural and acommissural subtypes. Both can present with variable degrees of the aortic stenosis (AS) and/or aortic valve regurgitation (AR).UAV has more early, accelerated and severe valvular degeneration in addition to smaller orifice in comparison with bicuspid and tricuspid aortic valve. Echocardiography is the gold standard for diagnosis and evaluation of the AV morphology and function and the associated disorders such as ventricular septal defect , aortopathy and subaortic obstruction.. Surgical aortic valve replacement (AVR) and repair of the associated anomalies are the most common treatment modality .

Esin Isik

and 7 more

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