Microbial exposure during early human development primes fetal immune cells

The human fetal immune system begins to develop early during gestation; however, factors responsible for fetal immune-priming remain elusive. We explored potential exposure to microbial agents in utero and their contribution toward activation of memory T cells in fetal tissues. We profiled microbes across fetal organs using 16S rRNA gene sequencing and detected low but consistent microbial signal in fetal gut, skin, placenta, and lungs in the 2^nd trimester of gestation. We identified several live bacterial strains including Staphylococcus and Lactobacillus in fetal tissues, which induced in vitro activation of memory T cells in fetal mesenteric lymph node, supporting the role of microbial exposure in fetal immune-priming. Finally, using SEM and RNA-ISH, we visualized discrete localization of bacteria-like structures and eubacterial-RNA within 14^th weeks fetal gut lumen. These findings indicate selective presence of live microbes in fetal organs during the 2^nd trimester of gestation and have broader implications toward the establishment of immune competency and priming before birth.

Experimental evolution of a fungal pathogen into a gut symbiont

Gut microbes live in symbiosis with their hosts, but how mutualistic animal-microbe interactions emerge is not understood. By adaptively evolving the opportunistic fungal pathogenCandida albicansin the mouse gastrointestinal tract, we selected strains that not only had lost their main virulence program but also protected their new hosts against a variety of systemic infections. This protection was independent of adaptive immunity, arose as early as a single day postpriming, was dependent on increased innate cytokine responses, and was thus reminiscent of “trained immunity.” Because both the microbe and its new host gain some advantages from their interaction, this experimental system might allow direct study of the evolutionary forces that govern the emergence of mutualism between a mammal and a fungus.

Central Variant of Posterior Reversible Encephalopathy Syndrome - A Rare Case Report

Posterior Reversible Encephalopathy Syndrome (PRES) is a clinicoradiological condition associated with headache, altered mental status, dizziness and white matter vasogenic oedema in parieto-occipital region. It is often associated with hypertension but can also occur in diverse clinical settings like immunosuppression, eclampsia, etc. It is due to failure of autoregulatory mechanism of posterior circulation in response to change in blood pressure. We hereby report a rare case of central variant of PRES secondary to severe hypertension diagnosed with 3T MRI. Objective of reporting this case was to describe the imaging findings of typical and rare atypical patterns of PRES. A 71-year-old male hypertensive patient was referred for brain imaging with history of short period of loss of consciousness, headache and dizziness. MRI brain showed central variant pattern of PRES with preferential involvement of brainstem, thalami and periventricular white matter with sparing of frontal, parietal and occipital lobes. The patient was treated with anti-hypertensive after which patient's symptoms subsided. The patient was followed up conservatively. Atypical variants of PRES should be borne in mind when pontine hyperintensity is encountered in hypertensive patient.

Radiation-induced mineralizing microangiopathy in a case of recurrent craniopharyngioma. A case report

Mineralizing microangiopathy is a late complication of radiation-induced brain injury that occurs during the treatment of CNS malignancies in children and adults. Early diagnosis of the radiation-induced brain injury helps to tailor the radiation dose and prevent further complications. Here we describe an operated oatient with craniopharyngioma who underwent external beam radiotherapy. The patient developed gradual loss of vision after two years and a review CT scan revealed the local recurrence of tumour with dystrophic calcification of the basal ganglia, frontal and temporal subcortical regions representing recurrent craniopharyngioma with radiation-induced mineralizing microangiopathy.

Characteristic MR Imaging Findings of Neurocutaneous Melanosis. A Case Report

Neurocutaneous melanosis is a type of phakomatosis characterised by dermal, leptomeningeal and parenchymal melanocytic naevi. Here we describe a case of a 13-year-old boy with dermal and brain parenchymal melanosis without any leptomeningeal melanosis.

Chronic Pituitary Failure Resembling Sheehan's Syndrome Following a Bite of Russell's Viper. A Case Report

Hypopituitarism can be the sequela of a variety of causes like postpartum pituitary necrosis or Sheehan's syndrome, lymphocytic hypophysitis, trauma and encephalitis. A very rare cause is envenomation by a bite of a Russell's viper. Very few cases with documented imaging findings of chronic pituitary failure resulting from snake bite have been reported. We describe a case of hypopituitarism with clinical, endocrine and magnetic resonance (MR) imaging studies occurring as a delayed complication of snake bite.

Typical neuroradiological diagnosis of maple syrup urine disease as a precursor to clinical diagnosis. A case report

Maple syrup urine disease (MSUD) is a rare inherited metabolic disorder. It is due to decreased de-carboxylation of branched-chain amino acids (leucine, valine, and isoleucine) so their accumulation gives a characteristic maple syrup odour in urine and leads to severe neurological deterioration. Early diagnosis and dietary intervention prevent complications and may allow for normal intellectual development. Various types of MSUD exist, classical MSUD being the most common and severe form of this disease. We describe a case of classical MSUD in a four- month-old infant where the MR imaging suggested the diagnosis of MSUD prior to the clinical diagnosis which was further confirmed by laboratory techniques.

Case report: Ocular malformation with a 'double globe' appearance

Colobomatous cyst of the orbit is a rare congenital cystic malformation associated with ocular maldevelopment. Usually, the cyst is associated with a microphthalmic globe. We present a rare case of a unilateral large colobomatous cyst associated with a normal-sized globe, giving the appearance of a double globe on imaging.

Wilson's disease--a rare psychiatric presentation

The development of extrapyramidal syndrome characterised by rigidity, bradykinesia, dysphagia and dysarthria in a male individual with four distinct episodes of (mania like) behavioural disturbances with fairly good remission in a time frame of five years, in a male individual, was suspected to develop the neurological manifestations of Wilson's disease and was investigated. In the absence of Kayser-Fleischer ring by slit-lamp examination and with normal copper and ceruloplasmin serum levels, the diagnosis was possible because of the positive findings of the magnetic resonance imaging (MRI) studies and increased 24 hours urinary copper levels with the penicillamine challenge test. The findings and its implications are highlighted and discussed.

Congenital coronary artery anomalies: diagnosis with 64 slice multidetector row computed tomography coronary angiography: a single-centre study

Retrospective review of the congenital coronary artery (CA) anomalies detected by a 64-slice multidetector row computed tomographic (MDCT) angiography. The type of the anomaly, imaging characteristics, clinical relevance and the superiority of the MDCT over conventional coronary angiography are discussed. Multidetector row computed tomographic coronary angiography was carried out by the usual technique with 70 cc of non-ionic contrast agent and retrospective electrocardiogram gating. The volume data obtained were reconstructed in axial plane, along with volume-rendered three-dimensional reconstruction and virtual angioscopy in selected patients. The images were analysed by a radiologist, experienced in cardiac CT, and an experienced cardiologist. A retrospective review of the records was carried out, and subjects with congenital coronary anomalies were included in the study. Between 15 November 2005 and 27 February 2007, 1495 MDCT coronary angiograms were carried out. Eleven of them were found to have coronary anomalies. Five had absent left main CA. Two had interarterial course of the left main CA artery passing in between the right ventricular outflow tract and the root of aorta. In one patient, there was aberrant origin of right CA from the left aortic sinus with subsequent interarterial course and another one had aberrant origin of circumflex artery from the right aortic sinus. One patient each of congenitally absent circumflex artery and atresia of the right CA were found. Sixty-four slice MDCT coronary angiography provided accurate depiction of anomalous vessel origin and course along with the complex anatomical relation with the adjacent structures. CT can be considered as a first-line imaging method for delineating coronary arterial anomalies.

Polyostotic Paget's Disease with Sarcomatous Change in a Skull Lesion. A Case Report of Imaging Findings

The most serious complication of Paget's disease is sarcomatous degeneration of pagetic bone. Multifocal sarcomatous degeneration occurs mainly in polyostotic Paget's disease. Paget sarcomas are the most threatening sarcomas of bone irrespective of the histopathology, their prognosis being far more negative than primary sarcomas. Paget's disease is a common entity but osteosarcoma arising in Paget's disease is an infrequent complication. The skull involvement is even rarer. We report a case of malignant transformation of a skull lesion in a patient of polyostotic Paget's disease. Skull radiographs, computed tomography and magnetic resonance imaging scans of the tumour area show interesting results.

Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project

We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structure has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function.

Determination of complete nucleotide sequence of Hibiscus latent Singapore virus: evidence for the presence of an internal poly(A) tract

We have sequenced the complete genome of a hibiscus-infecting tobamovirus, Hibiscus latent Singapore virus (HLSV). The experimental host range of HLSV is similar to that of another distinct species of hibiscus infecting tobamovirus, Hibiscus latent Fort Pierce virus (HLFPV). The genomic structure of HLSV is similar to other tobamoviruses in general. It consists of a 5' untranslated region (UTR), followed by ORFs encoding for a 128 kDa protein and a 186 kDa readthrough protein, a 30 kDa movement protein (MP), 18 kDa coat protein (CP) and a 3' UTR. The unique feature of HLSV is the presence of a poly(A) tract within its 3' UTR. In our previous work, we have reported MP and CP sequences of HLSV and its phylogenetic analysis. Here we report the complete nucleotide sequence of HLSV, phylogenetic analysis of the nucleotide and amino acid sequences of 128/186 kDa ORFs and the presence of a uniquely located poly(A) tract within the 3' UTR.

Hibiscus virus S is a new subgroup II tobamovirus: evidence from its unique coat protein and movement protein sequences

The coat protein (CP) and movement protein (MP) sequences of a new tobamovirus infecting Hibiscus rosa-sinensis L were determined. The CP gene encodes 163 amino acid (aa) residues and with a theoretical molecular weight of 18.19 kDa. The MP gene encodes 282 amino acids and its theoretical molecular weight is 30.36 kDa. The nucleotide (nt) and aa sequences of the CP were 46.88 % to 51.63 % and 45.34 % to 57.06 % identical to other tobamoviruses, respectively. The nt and aa sequence identities of MP ranged from 38.81 % to 43.90 % and 30.85 % to 37.88 %, respectively. The predicted virion origin of assembly (OAS) was located in the CP gene. Phylogenetic trees generated based on the nt and aa sequences of both CP and MP genes indicate that this new virus clusters with members of subgroup II of tobamoviruses. Although this hibiscus virus shared a high nt and aa sequence identity with Sunn-hemp mosaic virus (SHMV), Western analysis showed that it is serologically unrelated to SHMV. We propose the name Hibiscus virus S (HVS) for this Singapore isolate. This is the first report on partial nt sequence of a tobamovirus that infects hibiscus.