Correlation between the radiological observation of isolated tertiary waves on an esophagram and findings on high-resolution esophageal manometry

Barium esophagrams are a frequently performed test, and radiological observations about potential abnormal esophageal motility, such as tertiary contractions, are commonly reported. We sought to assess the correlation between tertiary waves, and in particular isolated tertiary waves, on esophagrams and findings on non-synchronous high-resolution esophageal manometry. We retrospectively reviewed reports of esophagrams performed at a tertiary referral center and identified patients in whom tertiary waves were observed and a high-resolution esophageal manometry had been performed. We defined two groups; group 1 was defined as patients with isolated tertiary waves, whereas group 2 had tertiary waves and evidence of achalasia or an obstructing structural abnormality on the esophagram. We collected data on demographics, dysphagia score, associated findings on esophagram, and need for intervention. We reviewed the reports of 2100 esophagrams of which tertiary waves were noted as an isolated abnormality in 92, and in association with achalasia or a structural obstruction in 61. High-resolution manometry was performed in 17 patients in group 1, and five had evidence of a significant esophageal motility disorder and 4 required any intervention. Twenty-one patients in group 2 underwent manometry, and 18 had a significant esophageal motility disorder. An isolated finding of tertiary waves on an esophagram is rarely associated with a significant esophageal motility disorder that requires intervention. All patients with isolated tertiary waves who required intervention had a dysphagia to liquids. Tertiary contractions, in the absence of dysphagia to liquids, indicate no significant esophageal motility disorder.

FTO association and interaction with time spent sitting

Background/Objectives

Multiple studies have revealed an interaction between a variant in the FTO gene and self-reported physical activity on body-mass index (BMI). Physical inactivity, such as time spent sitting (TSS) has recently gained attention as an important risk factor for obesity and related diseases. It is possible that FTO interacts with TSS to affect BMI, and/or that FTO's putative effect on BMI is mediated through TSS.

Subjects/Methods

We tested these hypotheses in two cohorts of the Framingham Heart Study (FHS) (Offspring: n=3,430, and 3^rd Generation: n=3,888), and attempted to replicate our results in the Women's Health Initiative (WHI) (n= 4,756). Specifically, we examined whether an association exists between FTO and self-reported TSS, and whether an interaction exists between FTO and TSS on BMI, while adjusting for several important covariates such as physical activity.

Results

In FHS, we find a significant positive association between the BMI-increasing FTO allele and TSS. We find a similar trend in WHI. Mediation analyses suggest that the effect of FTO on BMI is mediated through TSS. In FHS, we find a significant interaction of FTO and TSS on BMI, whereby the association of TSS with BMI is greatest among those with more FTO risk alleles. In WHI, we also find a significant interaction, although the direction is opposite to that in FHS. In a meta-analysis of the two datasets, there is no net interaction of FTO with TSS on BMI.

Conclusions

Our study suggests that FTO exerts its effect on BMI, at least partly, through energy expenditure mechanisms such as TSS. Further research into the intersection of genetics, sedentary behavior, and obesity-related outcomes is warranted.

Single photon emitters in exfoliated WSe2 structures

Crystal structure imperfections in solids often act as efficient carrier trapping centres, which, when suitably isolated, act as sources of single photon emission. The best known examples of such attractive imperfections are well-width or composition fluctuations in semiconductor heterostructures (resulting in the formation of quantum dots) and coloured centres in wide-bandgap materials such as diamond. In the recently investigated thin films of layered compounds, the crystal imperfections may logically be expected to appear at the edges of commonly investigated few-layer flakes of these materials exfoliated on alien substrates. Here, we report comprehensive optical micro-spectroscopy studies of thin layers of tungsten diselenide (WSe2), a representative semiconducting dichalcogenide with a bandgap in the visible spectral range. At the edges of WSe2 flakes (transferred onto Si/SiO2 substrates) we discover centres that, at low temperatures, give rise to sharp emission lines (100 μeV linewidth). These narrow emission lines reveal the effect of photon antibunching, the unambiguous attribute of single photon emitters. The optical response of these emitters is inherently linked to the two-dimensional properties of the WSe2 monolayer, as they both give rise to luminescence in the same energy range, have nearly identical excitation spectra and have very similar, characteristically large Zeeman effects. With advances in the structural control of edge imperfections, thin films of WSe2 may provide added functionalities that are relevant for the domain of quantum optoelectronics.

Multimodality imaging of primary extrahepatic portal vein obstruction (EHPVO): what every radiologist should know

Portal vein thrombosis (PVT) is a frequent complication of liver cirrhosis, but it can also occur as a primary vascular disorder amid absent liver disease. Extrahepatic portal vein obstruction (EHPVO) refers to the obstruction of the extrahepatic portal vein with or without involvement of the intrahepatic portal vein branches, splenic and/or superior mesenteric vein. It is a distinct disorder that excludes PVT occurring in concurrence with liver cirrhosis or hepatocellular carcinoma. The term "EHPVO" implies chronicity and is principally reserved for a long-standing condition characterized by cavernous transformation of the portal vein. The most characteristic imaging manifestation is the formation of portoportal collaterals (via the venous plexi of Petren and Saint) that allow hepatopetal flow. However, this collateral circulation is insufficient resulting in clinically significant pre-hepatic portal hypertension, wherein the liver function and structure remain preserved until late. Although the long-term (more than 10 years) survival with controlled variceal bleeding is up to 100%, affected individuals have an impaired quality of life owing to portal cavernoma cholangiopathy, hypersplenism, neurocognitive dysfunction and growth retardation. Imaging diagnosis is not always straightforward as the collaterals can also present as a tumour-like solid mass that can be inadvertently biopsied. Moreover, EHPVO has its implications for the biliary tree, arterial circulation, liver/splenic volumes and stiffness, which merit proper understanding but have not been so well described in literature. In this review, we present the complete spectrum of the vascular, biliary and visceral changes with a particular emphasis on what our medical/surgical hepatology colleagues need to know from us in the pre-operative and post-operative settings.

Review article: portal vein obstruction--epidemiology, pathogenesis, natural history, prognosis and treatment

BACKGROUND

Portal vein obstruction may be due to portal vein thrombosis (PVT) or its sequale, the portal cavernoma. PVT is a common complication in liver cirrhosis, however, it may also occur as a primary vascular disorder, in absence of any liver disease.

AIM

To review the current knowledge on nomenclature, etiology, pathophysiology, clinical presentation, diagnostic workup and management of adult patients with obstruction in the portal vein, either as a primary vascular disease in adults, or as a complication of liver cirrhosis.

METHODS

A structured search in PubMed was performed using defined keywords (portal vein obstruction, extra-hepatic portal vein obstruction, PVT and portal cavernoma), including full text articles and abstracts in English language.

RESULTS

Several causes, operating both at local and systemic level, might play an important role in the pathogenesis of PVT. Frequently, more than one risk factor could be identified; however, occasionally no single factor is discernible. Diagnosis of portal vein obstruction depends on clinical presentation, imaging and laboratory investigations. Prompt treatment greatly affects the patient's outcome.

CONCLUSIONS

Portal vein obstruction occurring either due to thrombosis in the portal vein or due to the portal cavernoma, can contribute to significant morbidity and mortality in patients with or without cirrhosis. In recent years our understanding of etio-pathogenesis of portal vein obstruction has evolved tremendously, which has led to significant improvement in treatment outcomes. There are still areas where more studies are needed to better clarify the management issues of portal vein obstruction.

Multimodality imaging of obliterative portal venopathy: what every radiologist should know

Obliterative portal venopathy (OPV) is an important cause of non-cirrhotic portal hypertension, which is often erroneously misdiagnosed as cryptogenic cirrhosis. It has a worldwide distribution with majority of cases hailing from the Asian subcontinent. However, recently the disease has gained global attention particularly because of its association with human immunodeficiency virus infection and use of antiretroviral drug therapy (didanosine). As the name suggests, the disorder is characterized by sclerosis and obliteration of the intrahepatic portal vein branches (with attendant periportal fibrosis) leading to portal hypertension amid intriguingly little liver dysfunction. It primarily affects young adults who present with clinically significant portal hypertension in the form of episodes of variceal bleed; however, contrasting liver cirrhosis, the liver function and liver structure remain normal or near normal until late in the disease process. Radiological findings during advanced disease are often indistinguishable from cirrhosis often warranting a liver biopsy. Nevertheless, recent studies have suggested that certain imaging manifestations, if present, can help us to prospectively suggest the possibility of OPV. At imaging, OPV is characterized by a wide range of intrahepatic and/or extrahepatic portal venous abnormalities with attendant changes in liver and splenic volume and stiffness. We shall, through this pictorial review, appraise the literature and illustrate the germane radiological manifestations of OPV that can be seen using different imaging modalities including ultrasonography, CT, MRI, elastography and hepatic haemodynamic studies.

Knowledge, attitude and practices on needle-stick and sharps injuries in tertiary care cardiac hospital: a survey

AIMS

One of the potential hazards for health care workers (HCWs) is needle-stick and sharp injuries (NSSIs). The objective of the study was to assess the knowledge and attitude of health care workers about the NSSIs.

SETTINGS AND DESIGN

This was a cross-sectional survey conducted in the tertiary care cardiac center. The participants were health care workers including doctors, nurses, technicians, and housekeeping staff from the different areas of the hospital.

METHODS AND MATERIALS

This cross-sectional survey was conducted in the institute using a self-administered validated questionnaire. The participants consisted of a total of 190 HCWs namely doctors, nurses, technicians, and housekeeping staff.

STATISTICAL ANALYSIS USED

Nil.

RESULTS

Results showed maximum participant were in the age group of 20-30 years. 94.7% were aware about standard precautions. 91.5% knew about the procedure for reporting of NSSIs. Only 50.2% HCWs gave correct answers regarding disease transmission through needle stick and sharp injury. The prevalence of NSSIs was highest among nurses (38.4%), and needle on the disposable syringe (76.9%) was the most common source of NSSIs.

CONCLUSIONS

The survey revealed few gaps in the knowledge amongst HCWs about NSSIs like risks associated with needle-stick injuries and use of preventive measures, disassembling of needles prior to disposal. These gaps can be addressed by extensive education. As nurses were the most affected victim for the NSSIs, more emphasis should be given towards them for reducing the NSSIs.

Synthesis, in vitro Anticancer and Antimicrobial Evaluation of Novel Substituted Dihydropyrimidines

A series of 1,4-dihydropyrimidine derivatives 3(a-t) were prepared from Biginelli reactions by using ethyl acetoacetate, substituted benzaldehyde and thiourea in the presence of piperidine and ethanol. The compounds 3(a-t) were reacted with dimethylsulphate, diethylsulphate, butyl bromide and benzyl chloride to give the new series of compounds 4(a-t). The structures of the newly synthesized compounds 4(a-t) were established by IR, (1)H NMR, Mass spectra and elemental analysis. The synthesized compounds were evaluated for their in vitro anticancer activity by using Sulforhodamine B assay method against the growth of four humans cancer cell lines, antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and for antifungal activity against Candida albicans and Aspergillus niger. The compounds exhibited good anticancer activity and moderate antibacterial and antifungal activities. Compounds 4b, 4c, 4d, 4g, 4i, 4n, 4o, 4q and 4s showed significant anticancer activity when compared with the doxorubicin as a standard reference drug.

Paraduodenal pancreatitis

Paraduodenal pancreatitis is a distinct clinicopathological entity involving the duodenum and the pancreatic tissue in the vicinity of the minor papilla. Most afflicted patients are young alcoholic males who present clinically with upper abdominal pain, weight loss, nausea, and vomiting. Pancreatic tissue elements in the duodenal wall and impedance to exocrine pancreatic secretions at the minor papilla are key factors in the pathogenesis of this condition. On imaging, the condition may manifest as a solid fibrotic mass around the minor papilla or as cysts in the duodenum and the pancreaticoduodenal groove. Duodenal stenosis, biliary strictures, chronic calcifying pancreatitis, and pancreatic ductal dilatation are also often observed.