From the Cover: Microstructured barbs on the North American porcupine quill enable easy tissue penetration and difficult removal

North American porcupines are well known for their specialized hairs, or quills that feature microscopic backward-facing deployable barbs that are used in self-defense. Herein we show that the natural quill’s geometry enables easy penetration and high tissue adhesion where the barbs specifically contribute to adhesion and unexpectedly, dramatically reduce the force required to penetrate tissue. Reduced penetration force is achieved by topography that appears to create stress concentrations along regions of the quill where the cross sectional diameter grows rapidly, facilitating cutting of the tissue. Barbs located near the first geometrical transition zone exhibit the most substantial impact on minimizing the force required for penetration. Barbs at the tip of the quill independently exhibit the greatest impact on tissue adhesion force and the cooperation between barbs in the 0–2 mm and 2–4 mm regions appears critical to enhance tissue adhesion force. The dual functions of barbs were reproduced with replica molded synthetic polyurethane quills. These findings should serve as the basis for the development of bio-inspired devices such as tissue adhesives or needles, trocars, and vascular tunnelers where minimizing the penetration force is important to prevent collateral damage.     

Assessing Documentation of Critical Imaging Result Follow-up Recommendations in Emergency Department Discharge Instructions

To facilitate follow-up of critical test results across transitions in patient care settings, we implemented an electronic discharge module that enabled care providers to include follow-up recommendations in the discharge instructions. We assessed the impact of this module on documentation of follow-up recommendations for critical imaging findings in Emergency Department (ED) discharge instructions. We studied 240 patients with critical imaging findings discharged from the ED before (n?=?80) and after (n?=?160) implementation of the module. We manually reviewed hand-written forms and electronic discharge instructions to determine if follow-up recommendations were documented. Follow-up recommendations in ED discharge instructions increased from 60.0% (48/80) to 73.8% (118/160) post-module implementation (p?=?0.03), a relative increase of 23%. There was no significant change in the rate of documented critical imaging findings in the discharge instructions (77.5% [62/80] before the intervention and 76.9% [123/160] after the intervention; p?=?0.91). Implementation of a discharge module was associated with increased documentation of critical imaging finding follow-up recommendations in ED discharge instructions. However, one in four patients still did not receive adequate follow-up recommendations, suggesting further opportunities for performance improvement exist.     

Repeat Pulmonary Valve Replacement: Similar Intermediate-Term Outcomes With Surgical and Transcatheter Procedures

Objectives

This study compares 30-day, 1-year, and 3-year echocardiographic findings and clinical outcomes of transcatheter pulmonary valve-in-valve replacement (TPVR) and repeat surgical pulmonary valve replacement (SPVR).

Endoscopic ultrasound in the evaluation of pancreatic neoplasms-solid and cystic: A review

Pancreatic neoplasms have a wide range of pathology, from pancreatic adenocarcinoma to cystic mucinous neoplasms. Endoscopic ultrasound(EUS) with or without fine needle aspiration(FNA) is a helpful diagnostic tool in the work-up of pancreatic neoplasms. Its utility in pancreatic malignancy is well known. Over the last two decades EUS-FNA has become a procedure of choice for diagnosis of pancreatic adenocarcinoma. EUS-FNA is highly sensitive and specific for solid lesions, with sensitivities as high as 80%-95% for pancreatic masses and specificity as high as 75%-100%. Multiple aspects of the procedure have been studied to optimize the rate of diagnosis with EUS-FNA including cytopathologist involvement, needle size, suctioning and experience of endoscopist. Onsite pathology is one of the most important elements in increasing diagnostic yield rate in EUS-FNA. EUS-FNA is valuable in diagnosing rare and atypical pancreatic neoplasms including neuroendocrine, lymphoma and metastatic disease. As more and more patients undergo cross sectional imaging, cystic lesions of the pancreas are becoming a more common occurrence and EUS-FNA of these lesions can be helpful for differentiation. This review covers the technical aspects of optimizing pancreatic neoplasm diagnosis rate, highlight rare pancreatic neoplasms and role of EUS-FNA, and also outline the important factors in diagnosis of cystic lesions by EUS-FNA.     

Basis of Rise in Intracellular Sodium in Airway Hyperresponsiveness and Asthma

The aim of this study was to investigate the basis of disturbances in sodium transport in asthma and in airway hyperresponsiveness without symptoms of asthma (asymptomatic AHR). We measured the intracellular sodium (Na_i); activity of Na⁺/K⁺-ATPase in unstimulated cells (resting activity) and in cell homogenate under optimal conditions (maximal activity); and sodium influx, in mixed leukocytes of 15 normal subjects, 12 subjects with asymptomatic AHR, and 26 asthmatics with or without active symptoms. Resting Na⁺/K⁺-ATPase activity was the same as sodium influx, consistent with homeostasis. Compared with normal subjects, those with asymptomatic AHR or asthma with controlled symptoms had a twofold increase in sodium influx and Na_i. Symptomatic asthmatics also had a twofold increase in sodium influx but a fourfold elevation of Na_i. Maximal Na⁺/K⁺-ATPase activity was reduced by half in symptomatic asthmatics compared with normal subjects. The reduction of maximal Na⁺/K⁺-ATPase activity was associated with a significant decrease in ATP turnover per Na⁺/K⁺-ATPase molecule but not number of Na⁺/K⁺-ATPase molecules per cell. In summary, airway hyperresponsiveness with or without asthma is associated with increased sodium influx and Na in leukocytes. Resting activity of Na⁺/K⁺-ATPase is also increased as a compensatory response to the increased sodium influx, but it is achieved at the expense of higher Na_i. Symptomatic asthma is additionally associated with reduction in maximal activity of Na⁺/K⁺-ATPase, resulting in reduced capacity to handle the increase in sodium influx and consequent severe elevations in Na_i.     

Unilateral massive hemothorax in Dengue hemorrhagic fever: a unique presentation

Dengue hemorrhagic fever is a more serious form of disease characterised by plasma leakage syndrome, thrombocytopenia and disseminated intravascular coagulation. We present a 51 year old male who presented with fever, petechiae and acute onset of breathlessness. Emergency chest rhoentogram showed a massive right sided pleural effusion. On insertion of intercostal drain, there was a sudden gush of blood tinged fluid suggestive of hemothorax. There was no history of trauma or bleeding tendencies. Laboratory investigations revealed a raised hematocrit and severe thrombocytopenia. Dengue IgM was surprisingly positive. After aggressive supportive management the patient gradually improved and was discharged. While bilateral pleural effusion is a known occurrence in dengue hemorrhagic fever, massive hemothorax is unheard of. We report the first case in literature of dengue hemorrhagic fever presenting as unilateral massive hemothorax. A suspicion of dengue must also be borne in mind in cases of non-traumatic hemothorax especially in endemic areas.     

Hyperphagic short stature: A case report and review of literature

A 5?-year-old adopted girl was referred to us in view of short stature. After ruling out systemic illness, she was evaluated for growth hormone deficiency (GHD) by stimulation tests. The peak value was 3.47 ng/ml. She was then started on growth hormone (GH). At the end of 6 months of GH therapy, her height velocity was only 3 cm/year. There was a lack of attachment between the mother and the child. She had history of hyperphagia, stealing, and hoarding food. Psychiatry consultation confirmed that the child had appetite disorder, and hence was diagnosed as hyperphagic short stature (HSS). The girl and her parents are undergoing psychiatric therapy for the same. Psychosocial dwarfism seems to originate from serious disturbances in the mother-child relationship. These children mimic patients with GHD, but have poor response to GH therapy. This case underscores the importance of social environment in the growth of the individual.     

Bilateral,multicenteric metanephric adenoma associated with Wilms' tumor in a child: A rare presentation with important diagnostic and therapeutic implications

Metanephric adenoma is an uncommon benign renal tumor that occurs predominantly in adult females and rarely in children. On histomorphology it shows a resemblance to Wilms' tumor, nephrogenic rests and papillary renal cell carcinoma. Multifocality along with multicentricity has not been documented in English literature till date. From a diagnostic and therapeutic viewpoint, recognition of this entity is of the utmost importance, because it shows a favorable clinical outcome. We describe a rare case of bilateral, multicentric metanephric adenoma associated with triphasic Wilms' tumor (stage II) of the left kidney in a male child.     

Cadmium Induced Lipid Peroxidation and Effects on Glutathione Dependent Enzymes in Tissues of Labeo rohita

The present study is aimed to assess the oxidative stress biomarker in kidney and liver of Labeo rohita exposed to the sub-lethal concentrations of cadmium chloride. The fishes were exposed to 33.6, 67.1 and 100.6 mg L^?1 concentrations of cadmium chloride up to 96 h duration and the oxidative stress was monitored through the levels of lipid peroxidation (LPO), reduced glutathione and activities of antioxidant enzymes, viz. glutathione peroxidase (GPx) and glutathione-S-transferase (GST). The malondialdehyde content, level of reduced glutathione and activities of antioxidant enzymes were significantly (p < 0.05) elevated in treated groups with the increasing concentration and exposure duration. Regression analysis showed a significant positive correlation between elevated levels of LPO and reduced glutathione (r ² = 0.999 and 0.991 in liver and kidney, respectively) as well as glutathione and its dependent enzymes (r ² = 0.999 and 0.996 with GPx and GST, respectively) at 96 h post-exposure in both the tissues of L. rohita. Further, the increased level of reduced glutathione and activity of glutathione dependent enzymes were not effective in reducing the cadmium induced oxidative stress in the fish. These assays may be employed to monitor oxidative stress mediated macro-molecular damage in aquatic organisms due to heavy metal exposure.