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1.
Development ; 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32747434

RESUMO

Central nervous system (CNS) blood vessels contain a functional blood-brain barrier (BBB) that is necessary for neuronal survival and activity. Although Wnt/ß-catenin signaling is essential for BBB development, its downstream targets within the neurovasculature remain poorly understood. To identify targets of Wnt/ß-catenin signaling underlying BBB maturation, we performed a microarray analysis that identified Fgfbp1 as a novel Wnt/ß-catenin-regulated gene in mouse brain endothelial cells (mBECs). Fgfbp1 is expressed in the CNS endothelium and secreted into the vascular basement membrane during BBB formation. Endothelial genetic ablation of Fgfbp1 results in transient hypervascularization but delays BBB maturation in specific CNS regions as evidenced by both upregulation of Plvap and increased tracer leakage across the neurovasculature due to reduced Wnt/ß-catenin activity. In addition, collagen IV deposition in the vascular basement membrane is reduced in mutant mice, leading to defective endothelial cell-pericyte interactions. Fgfbp1 is required cell-autonomously in mBECs to concentrate Wnt ligands near cell junctions and promote maturation of their barrier properties in vitro Thus, Fgfbp1 is a critical extracellular matrix protein during BBB maturation that regulates cell-cell interactions and Wnt/ß-catenin activity.

2.
Development ; 147(9)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358096

RESUMO

Neurovascular pathologies of the central nervous system (CNS), which are associated with barrier dysfunction, are leading causes of death and disability. The roles that neuronal and glial progenitors and mature cells play in CNS angiogenesis and neurovascular barrier maturation have been elucidated in recent years. Yet how neuronal activity influences these processes remains largely unexplored. Here, we discuss our current understanding of how neuronal and glial development affects CNS angiogenesis and barriergenesis, and outline future directions to elucidate how neuronal activity might influence these processes. An understanding of these mechanisms is crucial for developing new interventions to treat neurovascular pathologies.

3.
Cureus ; 11(9): e5655, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31700756

RESUMO

 Visceral artery aneurysms (VAAs) and visceral artery pseudoaneurysms (VAPAs) are often found incidentally through imaging of a patient presenting with vague symptoms of abdominal pain, hematochezia, hematemesis, and melena. Due to the asymptomatic nature, the etiology is often unknown. However, suspicion for VAA and VAPA should remain high for those presenting with symptoms listed above after trauma or pancreatitis. Here we discuss a case of traumatic ileocolic pseudoaneurysm that has only been discussed a handful of times in the literature.

4.
Microb Pathog ; 137: 103714, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31493502

RESUMO

Leprosy, once considered as poor man's disease may cause severe neurological complications and physical disabilities. Classification of leprosy depends upon the cell mediated and humoral immune responses of the host, from tuberculoid to lepromatous stage. Current therapy to prevent the disease is not only very lengthy but also consists of expensive multiple antibiotics in combination. Treatment and the duration depend on the bacillary loads, from six months in paucibacillary to a year in multibacillary leprosy. Although as per WHO recommendations, these antibiotics are freely available but still out of reach to patients of many rural areas of the world. In this review, we have focused on the nutritional aspect during the multi-drug therapy of leprosy along with the role of nutrition, particularly malnutrition, on susceptibility of Mycobacterium leprae and development of clinical symptoms. We further discussed the diet plan for the patients and how diet plans can affect the immune responses during the disease.


Assuntos
Dieta , Hanseníase/tratamento farmacológico , Hanseníase/imunologia , Desnutrição , Antígenos de Bactérias/farmacologia , Citocinas/metabolismo , Alimentos , Predisposição Genética para Doença , Humanos , Imunidade , Imunidade Humoral , Hanseníase/diagnóstico , Hanseníase/metabolismo , Masculino , Mycobacterium leprae/imunologia , Estado Nutricional , Fatores de Risco , Selênio , Vitaminas , Zinco
5.
Dalton Trans ; 48(34): 13057-13063, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31407762

RESUMO

Studtite, [UO2(η2-O2)(H2O)2]·2H2O, and metastudtite, [UO2(η2-O2)(H2O)2], are important phase alterations of UO2 in a spent nuclear fuel repository and have previously been shown to react with Np(v). In this work we extend the study to Am(v) on a tracer scale and show spectroscopic evidence that the Am is incorporated into the structure of studtite as Am(iii). A computational study on the possible mechanisms for the incorporation of Np and Am shows that protonation of the -yl oxygen is the favoured route and the calculated incorporation energies are large and positive. The results suggest that Am is less favoured compared to Np but energetically more favoured to incorporate both actinide ions into metastudtite rather than studtite. Finally, we have shown that once incorporated, Am readily leaches into water but spectroscopic measurements suggest subtle changes in the structure of studtite.

6.
Bull Emerg Trauma ; 7(2): 183-186, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31198809

RESUMO

Identification of any variant anatomy prior to surgery is as essential as having knowledge of normal anatomy. These surprises bring on many challenges along with as they can be fatal. We encountered a case of patient who succumbed down to an unrecognized rare mesenteric vasculature variant known as "Arc of Buhler" (AOB) which is a persistent embryonic ventral anastomosis between the Celiac trunk and the Superior mesenteric artery. It is usually asymptomatic and found incidentally after evaluation for other pathologies. We herein report a pseudoaneurysm of Arc of Buhler being surgically managed after massive retroperitoneal hemorrhage. Unfortunately, the patient did not survive the procedure and passed away. AOB aneurysms present formidable risks to patients and diagnostic and therapeutic challenges to physicians. They are rare and require high index of suspicion on radiographic imaging. Present case reports underscore the importance of identifying it and treating it regardless of the size.

7.
Bull Emerg Trauma ; 7(2): 187-191, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31198810

RESUMO

Bilateral inferior shoulder dislocations also known as luxatio erecta is an extremely rare injury that is commonly complicated with injuries to the humeral head, glenoid, clavicle, scapula, rotator cuff, capsule, ligaments, brachial plexus, axillary artery and vein.  Our patient is a 66-year-old man who presented with both upper extremities above his head in a fixed abducted position after sliding down a ladder approximately 6-meters. Initial radiographs revealed both humeral heads to be located below the glenoid fossa with each humeral shaft parallel to the scapular spines.  Computed tomography (CT) revealed a right Hill-Sachs compression fracture (posterolateral humeral head) with a bony Bankart fracture (anteroinferior glenoid) and an avulsion fracture of the left acromion. Successful closed reduction was obtained.  Upon follow up, bilateral rotator cuff tears were suspected and confirmed with magnetic resonance imaging (MRI).  Early recognition, treatment and follow-up is essential to minimize complications.

8.
Cardiol Res ; 10(2): 114-119, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31019641

RESUMO

Penetrating cardiac injuries are highly lethal and carry high mortality rate. Both blunt and penetrating cardiac injuries in patients who survive are known to present with well-known sequelae that often appear days to weeks after the initial insult. In the literature there have been documented cases of cardiac injury induced myocardial infarction, ventricular aneurysms, valvular dysfunction and even fistulous tracts between the coronary vessels and chamber. Although the most commonly injured vessel is the left anterior descending (LAD) coronary artery, traumatic injuries to the left coronary artery result in early death in the majority of cases. We present a unique case of LAD pseudo aneurysm and stenosis presenting as acute coronary syndrome (ACS) months after the initial penetrating cardiac injury successfully managed by stenting. There are only few isolated case reports of coronary artery pseudoaneurysm following penetrating chest trauma published in English literature.

9.
FASEB J ; : fj201800232R, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29874128

RESUMO

Proper arteriovenous morphogenesis is crucial for maintaining normal tissue perfusion. However, our understanding of how arterial morphogenesis is regulated in the CNS is incomplete. In this study, we asked whether vascular basement membrane (BM) laminins, specifically the γ3-containing isoforms, regulate retinal arterial morphogenesis. We provide evidence that Laminin-γ3 is deposited at both arterial and venous BMs during arteriogenesis. Vascular BM Laminin-γ3 bound dystroglycan (DG), a laminin receptor preferentially expressed by arterial endothelial cells (ECs) during arteriogenesis. Blockade of laminin-DG binding in vitro led to decreased Delta-like ligand (DLL)-4 expression in ECs. Moreover, genetic deletion of the Laminin-γ3- and EC-specific deletion of DG led to similar defects in retinal arteriogenesis, including reduced Dll4 expression, hyperbranching and reduced smooth muscle coverage. These results implicate a newly identified Laminin-γ3-DG signaling cascade that regulates arterial Dll4/Notch signaling to specify and stabilize retinal arteries.-Biswas, S., Watters, J., Bachay, G., Varshney, S., Hunter, D. D., Hu, H., Brunken, W. J. Laminin-dystroglycan signaling regulates retinal arteriogenesis.

10.
Inorg Chem ; 57(4): 1735-1743, 2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400951

RESUMO

The minerals studtite, [UO2(η2-O2)(H2O)2]·2H2O, and metastudtite, [UO2(η2-O2)(H2O)2], are uranyl peroxide minerals that are major oxidative alteration phases of UO2 under conditions of geological storage. The dehydration of studtite has been studied using X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy. XPS of the U 4f region shows small but significant differences between studtite and metastudtite, with the 4f binding energy of studtite being the highest reported for a uranyl mineral studied by this technique. Further information about the changes in the electronic structure was elucidated using U M4-edge high-energy resolution X-ray absorption near-edge structure (HR-XANES) spectroscopy, which directly probes f orbital states. The transition from the 3d to 5fσ* orbital is sensitive to variations in the U═Oaxial bond length and to changes in the bond covalency. We report evidence that the covalence in the uranyl fragment decreases upon dehydration. Photoluminescence spectroscopy at near-liquid helium temperatures reveals significant spectral differences between the two materials, correlating with the X-ray spectroscopy results. A theoretical investigation has been conducted on the structures of both studtite and metastudtite and benchmarked to the HR-XANES spectra. These illustrate the sensitivity of the 3d to 5f σ* transition toward U═Oaxial bond variation. Small structural changes upon dehydration have been shown to have an important electronic effect on the uranyl fragment.

11.
Inorg Chem ; 56(23): 14426-14437, 2017 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-29144747

RESUMO

A series of complexes [Et4N][Ln(NCS)4(H2O)4] (Ln = Pr, Tb, Dy, Ho, Yb) have been structurally characterized, all showing the same structure, namely a distorted square antiprismatic coordination geometry, and the Ln-O and Ln-N bond lengths following the expected lanthanide contraction. When the counterion is Cs+, a different structural motif is observed and the eight-coordinate complex Cs5[Nd(NCS)8] isolated. The thorium compounds [Me4N]4[Th(NCS)7(NO3)] and [Me4N]4[Th(NCS)6(NO3)2] have been characterized, and high coordination numbers are also observed. Finally, attempts to synthesize a U(III) thiocyanate compound has been unsuccessful; from the reaction mixture, a heterocycle formed by condensation of five MeCN solvent molecules, possibly promoted by U(III), was isolated and structurally characterized. To rationalize the inability to isolate U(III) thiocyanate compounds, thin-layer cyclic voltammetry and IR spectroelectrochemistry have been utilized to explore the cathodic behavior of [Et4N]4[U(NCS)8] and [Et4N][U(NCS)5(bipy)2] along with a related uranyl compound [Et4N]3[UO2(NCS)5]. In all examples, the reduction triggers a rapid dissociation of [NCS]- ions and decomposition. Interestingly, the oxidation chemistry of [Et4N]3[UO2(NCS)5] in the presence of bipy gives the U(IV) compound [Et4N]4[U(NCS)8], an unusual example of a ligand-based oxidation triggering a metal-based reduction. The experimental results have been augmented by a computational investigation, concluding that the U(III)-NCS bond is more ionic than the U(IV)-NCS bond.

12.
Bull Emerg Trauma ; 5(4): 303-306, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29177179

RESUMO

Traumatic iliac vessels injuries secondary to gunshot wound can often be fatal at the scene. One of the intriguing complications of vascular injuries is arteriovenous fistula. If the patient survives, these lesions may often not be diagnosed on first evaluation and patients may present with clinical signs and symptoms years later. Open surgical repair can have prohibitive morbidity and mortality and endovascular techniques, an effective treatment alternative, can interrupt the abnormal vascular communication and preserve artery vein patency. We describe a unique case of iliac arteriovenous fistula (AVF), secondary to a bullet injury, identified by imaging studies and subsequently treated with endovascular surgery. In conclusion, traumatic AVF are rare. Traditional teaching mandates that zone III pelvic retroperitoneal hematomas secondary to penetrating trauma be explored.

13.
Case Rep Surg ; 2017: 8412927, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29130015

RESUMO

Type IV paraesophageal hernia (PEH) is very rare and is characterized by the intrathoracic herniation of the abdominal viscera other than the stomach into the chest. We describe a case of a 90-year-old male patient who presented at our emergency department complaining of epigastric pain that he had experienced over the past few hours and getting progressively worse. On the day after admission, his pain became severe. Chest radiography revealed an intrathoracic intestinal gas bubble; emergency exploratory laparotomy identified a type IV PEH with herniation of only the jejunum with perforated diverticula on mesenteric side through a hiatal defect into mediastinum. There are a few published cases of small bowel herniation into the thoracic cavity in the literature. Our patient represents a rare case of an individual diagnosed with type IV PEH with herniation of jejunum with perforated diverticula.

14.
Gastroenterology Res ; 10(5): 318-321, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29118875

RESUMO

Peliosis hepatis (PH) is a rare vascular condition of the liver characterized by the presence of cystic blood filled cavities distributed randomly throughout the liver parenchyma. We describe a case of a 42-year-old previously healthy male patient, airlifted to us in a state of hemorrhagic shock after undergoing percutaneous diagnostic liver biopsy for lesions seen on CT scan. Repeat CT scan with IV contrast on presentation in our hospital showed intraperitoneal bleeding. Hepatic angiography failed to identify any specific bleeding source. A diagnostic laparoscopy was performed and approximate 9 L of hemoperitoneum was evacuated. The postoperative course was complicated with rapid hemodynamic deterioration, associated with acute hepatic failure progressively leading to multiorgan failure and death in spite of aggressive intensive care support. We suggest that PH should be considered as differential diagnosis of hypervascular hepatic lesions. It potentially can cause fatal acute non-traumatic liver hemorrhage.

15.
Am J Pathol ; 187(9): 2112-2127, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28697326

RESUMO

Retinal vascular diseases are among the leading causes of acquired blindness. In recent years, retinal microglia have been shown to influence vascular branching density and endothelial cell proliferation. However, how microglial recruitment and activation are regulated during development remains unclear. We hypothesized that microglial recruitment, activation, and down-stream signaling are modulated by components of the mural basement membrane. We used a reverse genetic approach to disrupt laminin expression in the vascular basement membrane and demonstrate that microglia respond to the mural basement membrane in an isoform-specific manner. Microglial density is significantly increased in the laminin γ3-null (Lamc3-/-) retinal superficial vascular plexus and consequently the vascular branching density is increased. Microglia also respond to astrocyte-derived matrices and become hyperactivated in the Lamc3-/- retina or when tested in vitro with cell-derived matrix. Pharmacological activation of microglia in the wild-type retina produced an Lamc3-/--like vascular phenotype, whereas pharmacological blocking of microglial activation in the Lamc3-/- retina rescued the wild-type vascular phenotype. On the molecular level, microglial transforming growth factor-ß1 expression is down-regulated in the Lamc3-/- retina, and SMAD signaling decreased in endothelial cells with a consequent increase in endothelial proliferation. The reverse effects were seen in the Lamb2-/- retina. Together, our results demonstrate a novel mechanism by which laminins modulate vascular branching and endothelial cell proliferation during retinal angiogenesis.


Assuntos
Astrócitos/metabolismo , Laminina/metabolismo , Microglia/metabolismo , Neovascularização Retiniana/metabolismo , Animais , Astrócitos/patologia , Membrana Basal/metabolismo , Membrana Basal/patologia , Células Endoteliais/metabolismo , Laminina/genética , Camundongos , Microglia/patologia , Retina/metabolismo , Retina/patologia , Neovascularização Retiniana/patologia , Fator de Crescimento Transformador beta1/metabolismo
16.
Case Rep Emerg Med ; 2017: 8079674, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28246563

RESUMO

Profunda femoris artery (PFA) pseudoaneurysm after blunt trauma without associated femur fracture is a rare occurrence. Most of the reported cases of PFA pseudoaneurysm in the English literature developed after penetrating trauma, surgical procedures, and femur fractures. We present two such cases following blunt trauma and without any associated long bone injury. After initial imaging failed to show any long bone fracture, CT angiography confirmed pseudoaneurysm of the branch of the PFA. Both patients were then treated with emergent coil embolization of the bleeding vessel. Pseudoaneurysms typically present late and signs of persistent hip pain, thigh swelling, presence of a pulsatile mass, and even unexplained anemia all may suggest the diagnosis. Recognition of PFA pseudoaneurysm requires high index of suspicion and is often difficult to diagnose clinically because of its location.

17.
Eplasty ; 16: ic19, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27298708
18.
Eplasty ; 16: ic21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27298710
19.
Dalton Trans ; 45(15): 6383-93, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27028717

RESUMO

The reaction of a number of uranyl minerals of the (oxy)hydroxide, phosphate and carbonate types with Eu(iii), as a surrogate for Am(iii), have been investigated. A photoluminescence study shows that Eu(iii) can interact with the uranyl minerals Ca[(UO2)6(O)4(OH)6]·8H2O (becquerelite) and A[UO2(CO3)3]·xH2O (A/x = K3Na/1, grimselite; CaNa2/6, andersonite; and Ca2/11, liebigite). For the minerals [(UO2)8(O)2(OH)12]·12H2O (schoepite), K2[(UO2)6(O)4(OH)6]·7H2O (compreignacite), A[(UO2)2(PO4)2]·8H2O (A = Ca, meta-autunite; Cu, meta-torbernite) and Cu[(UO2)2(SiO3OH)2]·6H2O (cuprosklodowskite) no Eu(iii) emission was observed, indicating no incorporation into, or sorption onto the structure. In the examples with Eu(3+) incorporation, sensitized emission is seen and the lifetimes, hydration numbers and quantum yields have been determined. Time Resolved Laser Induced Fluroescence Spectroscpoy (TRLFS) at 10 K have also been measured and the resolution enhancements at these temperatures allow further information to be derived on the sites of Eu(iii) incorporation. Infrared and Raman spectra are recorded, and SEM analysis show significant morphology changes and the substitution of particularly Ca(2+) by Eu(3+) ions. Therefore, Eu(3+) can substitute Ca(2+) in the interlayers of becquerelite and liebigite and in the structure of andersonite, whilst in grimselite only sodium is exchanged. These results have guided an investigation into the reactions with (241)Am on a tracer scale and results from gamma-spectrometry show that becquerelite, andersonite, grimselite, liebigite and compreignacite can include americium in the structure. Shifts in the U[double bond, length as m-dash]O and C-O Raman active bands are similar to that observed in the Eu(iii) analogues and Am(iii) photoluminescence measurements are also reported on these phases; the Am(3+) ion quenches the emission from the uranyl ion.

20.
World J Oncol ; 7(2-3): 34-39, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28983361

RESUMO

Non-melanoma skin cancer is the most common malignancy amongst Caucasians worldwide with basal cell and squamous cell cancer being the most common. Giant skin cancers are a relatively rare type of skin cancer that are, by definition, greater than 5 cm. This subtype by itself is associated with a significantly increased risk of complications and mortality. Myiasis is defined as infestation of body tissues of humans by dipterous larvae. Myiasis is often associated with malignant skin conditions. We describe a rare case of cutaneous myiasis located on a giant squamous cell carcinoma of the scalp in an elderly female. Myiasis coupled with malignant skin conditions provides a unique surgical challenge. This is especially true if the malignancy is invasive, as in our case, often requiring a multidisciplinary multimodality treatment plan.

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