Cyclophilin A associates with and regulates the activity of ZAP70 in TCR/CD3-stimulated T cells

The ZAP70 protein tyrosine kinase (PTK) couples stimulated T cell antigen receptors (TCRs) to their downstream signal transduction pathways and is sine qua non for T cell activation and differentiation. TCR engagement leads to activation-induced post-translational modifications of ZAP70, predominantly by kinases, which modulate its conformation, leading to activation of its catalytic domain. Here, we demonstrate that ZAP70 in TCR/CD3-activated mouse spleen and thymus cells, as well as human Jurkat T cells, is regulated by the peptidyl-prolyl cis-trans isomerase (PPIase), cyclophilin A (CypA) and that this regulation is abrogated by cyclosporin A (CsA), a CypA inhibitor. We found that TCR crosslinking promoted a rapid and transient, Lck-dependent association of CypA with the interdomain B region, at the ZAP70 regulatory domain. CsA inhibited CypA binding to ZAP70 and prevented the colocalization of CypA and ZAP70 at the cell membrane. In addition, imaging analyses of antigen-specific T cells stimulated by MHC-restricted antigen-fed antigen-presenting cells revealed the recruitment of ZAP70-bound CypA to the immunological synapse. Enzymatically active CypA downregulated the catalytic activity of ZAP70 in vitro, an effect that was reversed by CsA in TCR/CD3-activated normal T cells but not in CypA-deficient T cells, and further confirmed in vivo by FRET-based studies. We suggest that CypA plays a role in determining the activity of ZAP70 in TCR-engaged T cells and impact on T cell activation by intervening with the activity of multiple downstream effector molecules.

Deep Learning Approach for Analyzing the COVID-19 Chest X-Rays

Purpose

The purpose of this study is to analyze the utility of Convolutional Neural Network (CNN) in medical image analysis. In this study, deep learning (DL) models were used to classify the X-ray into COVID, viral pneumonia, and normal categories.

Materials and Methods

In this study, we have compared the results 9 layers CNN model (9 LC) developed by us with 2 transfer learning models (Visual Geometry Group) 16 and VGG19. Two different datasets used in this study were obtained from the Kaggle database and the Radiodiagnosis department of our institution.

Results

In our study, VGG16 yields the highest accuracy among all three models for different datasets as the Kaggle dataset-94.96% and the department of Radiodiagnosis dataset 85.71%. Although, the precision was found better while using 9 LC and VGG19 for both datasets.

Conclusions

DL can help the radiologists in the speedy prediction of diseases and detecting minor features of the disease which may be missed by the human eye. In the present study, we have used three models, i.e.,, CNN with 9 LCs, VGG16, and VGG19 transfer learning models for the classification of X-ray images with good accuracy and precision. DL may play a key role in analyzing the medical image dataset.

Dysregulated mitogen-activated protein kinase pathway mediated cell cycle disruption in sporadic parathyroid tumors

OBJECTIVES

The study was designed to evaluate expression profiling of mitogen-activated protein kinase (MAPK) signalling pathway genes in sporadic parathyroid adenoma.

METHODS

Expression of MAPK signalling pathway genes including activated transcription factors and cell cycle regulatory genes was analysed by real-time PCR- based array in parathyroid adenoma (N = 20) and normal parathyroid tissue (N = 4).

RESULTS

MAPK signalling pathway as studied by PCR array revealed that a total of 22 genes were differentially expressed (≥ twofold change, p ≤ 0.05) in parathyroid adenoma. Up-regulated genes were ARAF, MAPK12, CREBBP, MYC, HSPB1, HRAS, CDK4, CCND1, and E2F1, and down-regulated genes were MAP4K1, DLK1, MAP3K4, MAPK10, MAPK8, ATF2, SMAD4, MEF2C, LAMTOR3, FOS, CDKN2A CDKN2B, and RB1. The present study revealed that ERK1/2 signalling pathway with up-regulation of HRAS, ARAF, and MEK1 genes and up-regulation of positive regulators of cell cycle (CCND1, CDK4, and E2F1) and down-regulation negative regulators of cell cycle (CDKN2A, CDKN2B, and RB1) made highly dysregulated MAPK signalling pathway in parathyroid adenoma. Expression of CDK4 was positively associated with plasma PTH level (r = 0.60, p = 0.04) and tumor weight (r = 0.80, p = 0.02) of the adenoma patients, respectively. Expression of CDKN2A was correlated negatively with PTH level (r = - 0.52, p = 0.04) of the adenoma patients.

CONCLUSION

The current study revealed that ERK pathway and associated cell cycle regulator genes are dysregulated in sporadic parathyroid adenoma.

Quantitative proteomics analysis of sporadic parathyroid adenoma tissue samples

OBJECTIVE

Molecular pathogenesis of parathyroid tumors is incompletely understood. Identification of novel molecules and understanding their role in parathyroid tumorigenesis by proteomics approach would be informative with potential clinical implications.

METHOD

Adenomatous (n = 5) and normal (n = 2) parathyroid tissue lysates were analyzed for protein profile by LC-MS/MS method and the proteins were classified using bioinformatics tools such as PANTHER and toppfun functional enrichment tool. Identified proteins were further validated by western blotting and qRT-PCR (n = 20).

RESULT

Comparative proteomics analysis revealed that a total of 206 proteins (74 upregulated and 132 downregulated) were differentially expressed (≥ twofold change) in adenomas. Bioinformatics analysis revealed that 48 proteins were associated with plasma membrane, 49 with macromolecular complex, 39 were cytoplasm, 38 were organelle related, 21 were cell junction and 10 were extracellular proteins. These proteins belonged to a diverse protein family such as enzymes, transcription factors, cell signalling, cell adhesion, cytoskeleton proteins, receptors, and calcium-binding proteins. The major biological processes predicted for the proteins were a cellular, metabolic and developmental process, cellular localization, and biological regulation. The differentially expressed proteins were found to be associated with MAPK, phospholipase C (PLC) and phosphatidylinositol (PI) signalling pathways, and with chromatin organization. Western blot and qRT-PCR analysis of three proteins (DNAJC2, ACO2, and PRDX2) validated the LC-MS/MS findings.

CONCLUSION

This exploratory study demonstrates the feasibility of proteomics approach in finding the dysregulated proteins in benign parathyroid adenomas, and our preliminary results suggest that MAPK, PLC and PI signalling pathways and chromatin organization are involved in parathyroid tumorigenesis.

Screening of Hyperglycemic Patients Admitted in Intensive Care Unit

Background & objectives: It is a prospective, randomized, controlled study involving adults admitted to medical Intensive care unit (ICU) who were receiving mechanical ventilation. Methods: On admission, patients were randomly assigned to receive intensive insulin therapy (maintenance of blood sugar at a level between 80 and 110 mg/dl) and were found to have hyperglycemic. We study the clinical profile of critically ill hyperglycemic patients and associated metabolic profiles of all such patients were analyzed in relation to final outcome. Results: The benefit of intensive insulin care was from 8.0 percent with conventional treatment to 4.6 percent (P<0.04, with adjustment for sequential analyses). Intensive insulin therapy to maintain blood glucose at or below 110mg per deciliter reduced the morbidity and motility among critically ill patients in the surgical intensive care unit. Hyperglycemia was present in 38% of patient admitted to the hospital, of whom 26% had a known history of diabetes, and 12% had no history of diabetes before admission. Interpretation & conclusions: New hyperglycemic patients had a longer length of hospital stay, a higher admission rate to an intensive care unit, and were less likely to be discharged to home, frequently requiring transfer to an intermediate care unit. DOI: http://dx.doi.org/10.3126/ajms.v5i1.8507   Asian Journal of Medical Science Vol.5(1) 2014 pp.63-69

Correlation of insulin resistance, beta cell function and insulin sensitivity with serum sFas and sFasL in newly diagnosed type 2 diabetes

Pancreatic beta cell dysfunction and reduced insulin sensitivity are fundamental factors associated with glucotoxicity, lipotoxicity and oxidative stress in type 2 diabetic patients (T2DM). Diabetic milieu can induce apoptosis in several types of cells. The aim of present study was to compare circulating soluble apoptotic markers (sFas and sFas-L) with HOMA-IR, HOMA-%S, HOMA-%B in the serum of newly diagnosed T2DM and healthy subjects. For this study, 94 T2DM and 60 healthy subjects were enroled and evaluated for various parameters. Biochemical quantifications were performed with Syncron CX5 auto-analyzer. The levels of serum sFas-L, TNF-α and IL-6 were estimated by flowcytometry. The fasting serum insulin and sFas quantified by ELISA. HOMA-IR, HOMA-%S and HOMA-%B were calculated with HOMA calculator v2.2.2. The levels of TC, TG, LDL-C, VLDL-C were augmented and HDL declined significantly (P < 0.001) in diabetics. The levels of serum insulin, TNF-α, IL-6, sFas, HOMA-IR were raised (P < 0.001) and sFas-L, HOMA-%S and HOMA-%B were decreased significantly (P < 0.001) in T2DM subjects than healthy. In diabetics, serum sFas was positively correlated with HOMA-IR (r = 0.720, P < 0.001) and negatively with HOMA-%B (r = -0.642, P < 0.001) significantly while serum sFasL was negatively correlated with HOMA-IR (r = -0.483, P < 0.001) and positively with HOMA-%B (r = 0.466, P < 0.001) significantly. Further, the multivariate stepwise regression analysis shows that HOMA-IR contributes significantly to the variance of sFas and sFasL. Our findings suggest that the pancreatic beta cell dysfunction along with increased insulin resistance appears to be associated with apoptotic markers.

Pseudomyxoma peritonei: An uncommon tumor

Pseudomyxoma peritonei is a poorly understood and uncommon tumor that is known for its production of mucin in the abdominal cavity and mucinous implants, diffusely involving the peritoneal surfaces. A 60-year-old female presented to us with post-op complaints of diffuse abdominal pain and distension. On work-up, she was diagnosed as a case of Pseudomyxoma peritonei (with residual disease). She received chemotherapy in the form of oral capecitabine for residual disease. She was totally asymptomatic till the last follow-up. This case is being reported on account of its rarity and to emphasize a simple alternative treatment option as compared to the standard one.

Nutlin-3, the small-molecule inhibitor of MDM2, promotes senescence and radiosensitises laryngeal carcinoma cells harbouring wild-type p53

BACKGROUND

Primary radiotherapy (RT) is a mainstay of treatment for laryngeal squamous cell carcinoma (LSCC). Although the cure rates for early (T1) vocal cord tumours are high, RT proves ineffective in up to a third of T3 carcinomas. Moreover, RT is associated with debilitating early- and late-treatment-related toxicity, thus finding means to de-escalate therapy, while retaining/augmenting therapeutic effectiveness, is highly desirable. p53 is a key mediator of radiation responses; we therefore investigated whether Nutlin-3, a small-molecule inhibitor of MDM2 (mouse double minute 2; an essential negative regulator of p53), might radiosensitise LSCC cells.

METHODS

We performed clonogenic assays to measure radiosensitivity in a panel of LSCC cell lines (for which we determined p53 mutational status) in the presence and absence of Nutlin-3.

RESULTS

LSCC cells harbouring wild-type p53 were significantly radiosensitised by Nutlin-3 (P<0.0001; log-rank scale), and displayed increased cell cycle arrest and significantly increased senescence (P<0.001) in the absence of increased apoptosis; thus, our data suggest that senescence may mediate this increased radiosensitivity.

CONCLUSION

This is the first study showing Nutlin-3 as an effective radiosensitiser in LSCC cells that retain wild-type p53. The clinical application of Nutlin-3 might improve local recurrence rates or allow treatment de-escalation in these patients.

What proportion of patients referred to an otolaryngology vertigo clinic have an otological cause for their symptoms?

Background:

Dizziness is a common and often complex complaint. Between nine and 13 per cent of patients seen in general practice are referred to a variety of specialist clinics. The diagnoses and outcomes of these referrals are seldom reported.

Aims:

To determine the proportion of patients referred to an otology led vertigo clinic in whom an otological cause for vertigo could be identified.

Design of study:

Prospective cohort study of consecutive new clinic attendees over one year.

Setting and methods:

Otology led vertigo clinic in an urban teaching hospital in England. Patients' details including age, sex, referring clinician, investigations, diagnoses, treatment and final outcome were recorded in an anonymised database.

Results:

91 new patients, 31 men and 60 women with a mean age of 52.6 years (range 16–81) were seen. General practitioners referred 87 per cent of the patients. Twenty-seven patients underwent further investigations including imaging, electronystagmography and other audiological tests. A labyrinthine disorder accounted for 50 per cent of the diagnoses. Ménière's disease or a variant was diagnosed in 20 patients (21 per cent). Fifty-six patients (61 per cent) reported resolution of or improvement in their symptoms. Thirty-one patients (34 per cent) were asymptomatic and free of abnormal findings on initial attendance and were discharged from hospital care.

Conclusions:

Forty-six patients (50.6 per cent, 95 per cent confidence interval, 40.4–60.6 per cent) had vertigo due to an otological disorder. The selection of an otolaryngology based vertigo clinic by the general practitioner for initial referral seems appropriate.

Techniques used for assessing the sense of smell

Assessment of the sense of smell is a challenging clinical investigation. Although a wide range of tests are available, many are modifications of tests designed more than 20 years ago. This article describes the smell tests that are available, and consider smell assessment after nasal surgery.

‘Complementary ENT’: a systematic review of commonly used supplements

Objective:

To assess the evidence surrounding the use of certain complementary supplements in otolaryngology. We specifically focussed on four commonly used supplements: spirulina, Ginkgo biloba, Vertigoheel® and nutritional supplements (cod liver oil, multivitamins and pineapple enzyme).

Materials and methods:

A systematic review of the English and foreign language literature. Inclusion criteria: in vivo human studies. Exclusion criteria: animal trials, in vitro studies and case reports. We also excluded other forms of ‘alternative medicine’ such as reflexology, acupuncture and other homeopathic remedies.

Results:

Lack of common outcome measures prevented a formal meta-analysis. Three studies on the effects of spirulina in allergy, rhinitis and immunomodulation were found. One was a double-blind, placebo, randomised, controlled trial (RCT) of patients with allergic rhinitis, demonstrating positive effects in patients fed spirulina for 12 weeks. The other two studies, although non-randomised, also reported a positive role for spirulina in mucosal immunity. Regarding the use of Ginkgo biloba in tinnitus, a Cochrane review published in 2004 showed no evidence for this. The one double-blind, placebo-controlled trial that followed confirmed this finding. Regarding the use of Vertigoheel in vertigo, two double-blind RCTs and a meta-analysis were identified. The first RCT suggested that Vertigoheel was equally effective in reducing the severity, duration and frequency of vertigo compared with betahistine. The second RCT suggested that Vertigoheel was a suitable alternative to G biloba in the treatment of atherosclerosis-related vertigo. A meta-analysis of only four clinical trials confirms that Vertigoheel was equally effective compared with betahistine, G biloba and dimenhydrinate. Regarding multivitamins and sinusitis, two small paediatric pilot studies reported a positive response for chronic sinusitis and otitis media following a course of multivitamins and cod liver oil. Regarding bromelain (pineapple enzyme) and sinusitis, one randomised, multicentre trial including 116 children compared bromelain monotherapy to bromelain with standard therapy and standard therapy alone, for the treatment of acute sinusitis. The bromelain monotherapy group showed a faster recovery compared with the other groups.

Conclusion:

The positive effects of spirulina in allergic rhinitis and of Vertigoheel in vertigo are based on good levels of evidence, but larger trials are required. There is overwhelming evidence that G biloba may play no role in tinnitus. There is limited evidence for the use of multivitamins in sinus symptoms, and larger randomised trials are required.

An innovative method of nasal chemical cautery in active anterior epistaxis

We present a method to cauterize an actively bleeding source in anterior epistaxis. In our experience, this method is efficient, provides full control of the bleeding, and ensures precise cautery of the bleeding source with minimal usage of chemical cautery sticks.

Double-blind randomized controlled study of coblation tonsillotomy versus coblation tonsillectomy on postoperative pain in children

OBJECTIVES

The purpose of this study was to establish if children experienced any difference in pain, between coblation tonsillectomy and coblation tonsillotomy.

DESIGN

A double-blind randomized controlled trial was performed.

SETTING

District general hospital department of Otolaryngology.

PARTICIPANTS

Eighteen children listed for tonsillectomy were recruited into the study. Each was randomly assigned either tonsillotomy or tonsillectomy in the right tonsil. The contralateral tonsil was removed by the other method. In the first 24-h period (while in hospital) the children were interviewed at 2, 5, 10 and 24 h to quantify the pain they perceived in right and left sides. There was a four point visual analogue scoring system for monitoring pain. The power of the study was 80%. In this study the patients were their own controls.

MAIN OUTCOME MEASURES

Visual analogue pain scores were plotted against time and the area under the curves was calculated (AUC).

RESULTS

The AUC mean difference was 0.47. A t-test for the difference gives a P-value of 0.85 and a 95% confidence interval for difference is -0.79 to 5.73, which clearly contains zero. Using AUC as a combined pain score there is no statistically significant difference between tonsillotomy and tonsillectomy (power value of 80%).

CONCLUSIONS

There is no demonstrable statistical difference between techniques when measuring pain experienced by children in the 24-h postoperative period.

The use of perioperative SofradexR eardrops in preventing tympanostomy tube blockage: a prospective double-blinded randomized-controlled trial

Around 11-12% of tympanostomy tubes are reported to become blocked by middle ear secretions or blood immediately following surgery, and so no longer function. Many otologists routinely instil an antibiotic and steroid-containing solution at the time of surgery in the belief that this may reduce this complication. The aim of the study was to investigate the efficacy of instilling the antibiotic and steroid-containing solution Sofradex at the time of grommet insertion in preventing grommet blockage. Double-blind randomized-controlled trial, comparing rates of grommet blockage in ears treated with Sofradex drops against control (no drops) in patients undergoing bilateral grommet insertion. Sixty-one pairs of results were obtained. There was a significant difference between the rates of grommet blockage in the two groups. Grommets with Sofradex drops instilled perioperatively were nine times less likely to be blocked than controls [1.6%versus 13.1%, odds ratio (Sofradex/control) = 9.06, 95% confidence interval (CI): 1.04-78.82, P = 0.05]. There was no association between grommet blockage and perioperative bleeding or the nature and presence of middle ear secretions. Sofradex eardrops are effective in reducing the rate of grommet blockage when instilled perioperatively.