A rare diagnosis of Langerhans cell histiocytosis made on thyroid histology with coexisting papillary thyroid cancer and AVP deficiency

Summary

A 48-year-old Asian male, presented to the hospital for an elective total thyroidectomy in the context of 6.3 cm thyroid nodule. The fine needle aspiration cytology of the nodule confirmed papillary thyroid cancer (PTC) with some atypical histiocytes. He has a history of idiopathic arginine vasopressin deficiency (AVP-D) and has been taking oral DDAVP 100 µg daily, self-adjusting the dose based on thirst and polyuria. Additionally, he also has a history of recurrent spontaneous pneumothorax. His total thyroidectomy was aborted due to significant intraoperative bleeding, and his admission was further complicated by post-operative hyponatraemic seizure. Thyroid histology revealed the diagnosis of Langerhans cell histiocytosis (LCH), and further investigation with contrast CT demonstrated multi-organ involvement of the thyroid, lungs, and bones.

Learning points

Langerhans cell histiocytosis (LCH) is a condition that can affect one or more organ systems, including the pituitary, where it can present as AVP deficiency. Strict monitoring of fluid balance, as well as serial monitoring of serum sodium, is essential in all patients with AVP-D in the perioperative setting. Iatrogenic hyponatraemic seizure is an uncommon but serious complication of DDAVP treatment in hospitalised patients with AVP-D. DDAVP dosing must be carefully monitored. LCH with multisystem involvement is an important mimic for metastatic conditions, and histological diagnosis is essential to guide treatment and prognosis. Although LCH without bone marrow involvement is unlikely to increase the risk of bleeding, its effect on tissue integrity may make surgery more challenging. BRAF-V600E mutation is an important driver mutation and a potential therapeutic target in the treatment of LCH.

Temperature dependent structural properties of Mn1.90M0.10O3(M = Cr and Fe)

The polycrystalline samples of Mn1.90Cr0.10O3(MCO) and Mn1.90Fe0.10O3(MFO) have been investigated for their temperature dependent magnetic and structural properties. The Cr and Fe substitutions have significant effect on the magnetic and structural properties of Mn2O3. Like pristine Mn2O3, the Cr and Fe substituted samples MCO and MFO also exhibit two antiferromagnetic transitions; one at ∼77 K, ∼80 K, respectively and another at ∼40 K. Our room temperature synchrotron x-ray powder diffraction (SXRD) results confirm that both the MCO and MFO samples crystallize in cubic symmetry. The temperature dependent SXRD results demonstrate the cubic to orthorhombic structural transition for the studied samples. The pristine Mn2O3shows cubic to orthorhombic transition around 310 K, whereas this structural transition shifted towards lower temperature side with these substitutions i.e. around 240 K for MCO and 260 K for MFO. Interestingly, the centrosymmetricPcabto non-centrosymmetricPca21change in symmetry is also resolved at the ferroelectric ordering temperature for MCO.

Enhanced external counter pulsation therapy in patients with symptomatic and severe intracranial steno-occlusive disease: a randomized clinical trial protocol

Intracranial stenosis is prevalent among Asians and constitutes a common cause of cerebral ischemia. While the best medical therapy carries stroke recurrence rates in excess of 10% per year, trials with intracranial stenting have been associated with unacceptable peri-procedural ischemic events. Cerebral ischemic events are strongly related to the severity of intracranial stenosis, which is high in patients with severe intracranial stenosis with poor vasodilatory reserve. Enhanced External Counter Pulsation (EECP) therapy is known to improve myocardial perfusion by facilitating the development of collateral blood vessels in the heart. In this randomized clinical trial, we evaluate whether EECP therapy may be useful in patients with severe stenosis of intracranial internal carotid (ICA) or middle cerebral artery (MCA). The review of literature, methods of evaluation, status of currently used therapeutic approaches, and trial protocol have been presented.

Clinical trial registration

ClinicalTrials.gov, Identifier: NCT03921827.

Comparative study of the short-range structure of α-V2O5, α-TeO2 and xV2O5-(100 - x)TeO2 glasses using X-ray diffraction, Rietveld analysis and reverse Monte Carlo simulations

Vanadium-tellurite glasses, tetragonal TeO₂ and orthorhombic V₂O₅ crystalline samples were characterized for their atomic structure properties by synchrotron X-ray diffraction, pair distribution function analysis, reverse Monte Carlo simulations (RMC) and Rietveld analysis. The pair correlation function, G(r), of V₂O₅ shows the first peak at 1.61 Å. G(r) of TeO₂ shows three peaks at 1.57, 2.13 and 2.88 Å due to Te-O linkages of three different lengths, whereas the Te-Te atomic pair correlation shows a peak at 3.85 Å. The average coordination number of V with O in crystalline V₂O₅ is 4.39 while that of Te with O in crystalline TeO₂ is 3.71. G(r) of the vanadium tellurite glass shows the first peak at 1.90 Å due to overlapping Te-O and V-O atomic pair correlations. The RMC analysis on diffraction data of glasses found that the V-O coordination number is in the range 5.27-5.59 and the Te-O coordination number is 5.39-5.67. However, it is found that these coordination numbers cannot be clearly defined due to short-range disorder.

Perceived stigma among diabetic patients and their caregivers: a review

AIMS

Considerable number of studies in the existing literature indicate the existence of stigma related to many diseases, disabilities, and disorders, but less attention has been given to diabetes-related stigma. This narrative review of literature aims to explore the existence of stigma surrounding type 1 diabetes mellitus (T1DM).

METHODS

Literature were searched using search engines, Google Scholar, PubMed, and Scopus electronic databases published from year 2000 to 2020. Both qualitative and quantitative studies focusing on the stigma associated with T1DM were included. A total of 21 articles met the inclusion criteria. Thematic analysis of collected research material was done.

RESULTS

Results provided substantial evidence that stigma associated with T1DM was experienced by T1DM patients and their caregivers at some point in their lives and it had affected their lives in different domains such as difficulty finding a spouse, discrimination at employment opportunities, educational institutions, management of disease, being misjudged as a druggie, poor quality of life of the patient and caregiver, depressive symptoms among parents of patients, constant worrying of their child's disease management, and so on.

CONCLUSION

Stigma related to T1DM is experienced by individuals suffering from it, and it is widespread. It not only affects the sufferers but their loved ones also. To reduce and cope-up with stigma, there is a need to increase public education and awareness at a mass level. Further research and awareness will serve to build our understanding of the experience of diabetes-related stigma.

Angiomatoid Fibrous Histiocytoma with EWSR1 Rearrangement in an Unusual Location

Introduction/Objective

Angiomatoid fibrous histiocytoma (AFH) is a rare mesenchymal neoplasm most often arising in the superficial extremities of children and young adults. AFH can mimic clinical, histologic, and radiologic presentation of several different tumors, therefore diagnosis can be quite challenging.

Methods/Case Report

We report the case of a 32-year-old woman with no significant medical history who presented with three days of right upper quadrant pain. Radiologic studies showed a 2.3 centimeter right lower lobe soft tissue nodule abutting the right lower lobe bronchus.

Results (if a Case Study enter NA)

Subsequent lobectomy with mediastinal lymph node dissection was performed. Histopathologic examination of the right middle and lower lobes revealed a fibrohistiocytic appearing neoplasm with bland nuclear features and brisk associated lymphoplasmacytic and histiocytic infiltrate. Given the suspicion for AFH, fluorescent in situ hybridization for EWSR1 and FUS were performed at an outside facility with detection of EWSR1 gene rearrangement supporting the diagnosis of AFH.

Conclusion

AFH is a rare soft tissue neoplasm that is often indolent but intermediate in potential given the rare possibility of metastasis. While most common in superficial extremities, increasing unusual anatomic sites are being reported. Histologically, the tumor can show a spectrum of morphologic patterns including nodules to sheets of often monomorphic bland, spindle or ovoid cells in an inflammatory background and with associated fibrous pseudocapsule. Three characteristic chromosomal translocations have been identified: EWSR1-CREB1, EWSR1-ATF1 and FUS- ATF1. Treatment is wide surgical excision or radiotherapy if unresectable. The differential diagnosis can be broad with a spectrum from reactive, benign lesions to malignant neoplasms, including a variety of sarcomas.

Structural correlations in the enhancement of ferroelectric property of Sr doped BaTiO3

The effect of Sr doping in BaTiO3(BTO) with nominal compositions Ba0.80Sr0.20TiO3(BSTO) have been explored on its structural, lattice vibration, dielectric, ferroelectric and electrocaloric properties. The temperature dependent dielectric results elucidate the enhancement in dielectric constant and exhibit three frequency independent transitions around 335, 250 and 185 K, which are related to different structural transitions. All these transitions occur at lower temperature as compared with pristine BTO, however; remnant electric polarization (Pr) of BSTO is much higher than in BTO. The value ofPris ∼5μC cm-2at room temperature and the maximumPr∼ 8μC cm-2is observed at tetragonal to orthorhombic and orthorhombic to rhombohedral transitions. The electro-caloric effect shows the maximum adiabatic change in temperature ΔT∼ 0.24 K at cubic to tetragonal transition. The temperature dependent synchrotron x-ray diffraction and Raman results show correlations betweenPr, crystal structure and lattice vibrations. Our results demonstrate the enhancement in ferroelectric properties of BTO with Sr doping. The origin of the enhancement in ferroelectric property is also discussed in correlations with the appearance of superlattice peak around room temperature due to TiO6octahedral distortion. These enhanced properties would be useful to design lead free high quality ferroelectric and piezoelectric materials.

Direct hybridization gap from intersite and onsite electronic interactions in CeAg2Ge2

Electronic and crystal structure studies are presented to describe the role of intersite and onsite interactions for antiferromagnetic ordering in CeAg2Ge2. The crystal structure showed a prominent magnetovolume effect with anomalous negative thermal expansion at low temperature as a consequence of itinerant electron magnetism. The direct hybridization gap with a V-shaped band observed in the angle resolved photoemission data at room temperature, indicates that spin polarized quasiparticle states exist in the gapped region. Valence band broadening and enhanced localization effects at low temperature indicate strong hybridization of the valence orbitals of Ce atoms with the near neighbor Ge atoms. We find that the intersite interaction between the Ce atoms at high temperature stabilizes the onsite interaction at low temperature that leads to the spin density wave type antiferromagnetism in CeAg2Ge2.

Combined pathologic-genomic algorithm for early-stage breast cancer improves cost-effective use of the 21-gene recurrence score assay

Background

The 21-gene recurrence score (RS) (Oncotype DX®; Genomic Health, Redwood City, CA) partitions hormone receptor positive, node negative breast cancers into three risk groups for recurrence. The Anne Arundel Medical Center (AAMC) model has previously been shown to accurately predict RS risk categories using standard pathology data. A pathologic-genomic (P-G) algorithm then is presented using the AAMC model and reserving the RS assay only for AAMC intermediate-risk patients.

Patients and methods

A survival analysis was done using a prospectively collected institutional database of newly diagnosed invasive breast cancers that underwent RS assay testing from February 2005 to May 2015. Patients were assigned to risk categories based on the AAMC model. Using Kaplan-Meier methods, 5-year distant recurrence rates (DRR) were evaluated within each risk group and compared between AAMC and RS-defined risk groups. Five-year DRR were calculated for the P-G algorithm and compared with DRR for RS risk groups and the AAMC model's risk groups.

Results

A total of 1268 cases were included. Five-year DRR were similar between the AAMC low-risk group (2.7%, n = 322) and the RS < 18 low-risk group (3.4%, n = 703), as well as between the AAMC high-risk group (22.8%, n = 230) and the RS > 30 high-risk group (23.0%, n = 141). Using the P-G algorithm, more patients were categorized as either low or high risk and the distant metastasis rate was 3.3% for the low-risk group (n = 739) and 24.2% for the high-risk group (n = 272). Using the P-G algorithm, 44% (552/1268) of patients would have avoided RS testing.

Conclusions

AAMC model is capable of predicting 5-year recurrences in high- and low-risk groups similar to RS. Further, using the P-G algorithm, reserving RS for AAMC intermediate cases, results in larger low- and high-risk groups with similar prognostic accuracy. Thus, the P-G algorithm reliably identifies a significant portion of patients unlikely to benefit from RS assay and with improved ability to categorize risk.

Reversal of the reversed 'Robin Hood syndrome' after superficial temporal-Middle cerebral artery bypass for severe intracranial stenosis

Background: Intracranial arterial stenosis is a common cause of ischemic stroke. Recent attempts with intracranial stenting and superficial temporal-middle cerebral artery (STA-MCA) bypass failed to show benefit. Perhaps, better strategies are needed for selecting suitable patients. Acetazolamide-challenged single photon emission computed tomography (SPECT) can demonstrate reversed Robin Hood syndrome (RRHS) due to intracranial steal phenomenon and identify high-risk patients.Methods: We describe the clinical and SPECT findings of RRHS.Results: In our patient with severe and symptomatic severe stenosis of the right MCA, STA-MCA bypass resulted in complete resolution of RRHS.Conclusion: STA-MCA bypass surgery should be considered a possible option in patients with severe stenosis of intracranial internal carotid artery or MCA in carefully selected patients.

Application of XANES in gamma dosimetry

The thermoluminescence material, CaSO₄:Dy, is widely used for the dosimetry of ionizing radiation due to its high sensitivity, low fading and wide dose range from μGy to few tens of gray. However, its application is limited at high doses due to non-linear and saturation effects. In this paper, X-ray Absorption Near Edge Structure (XANES) studies at the Dy L₃-edge have been carried out on CaSO₄:Dy discs exposed to gamma doses in the range 0-1000 Gy. The results show an increase in white line in XANES spectra with gamma dose. Structural change in CaSO₄:Dy also has been studied using X-Ray Diffraction (XRD) and has found no structural change up to 1000 Gy. The study indicates that XANES can be used as an alternative dosimetry technique and is useful in the evaluation of absorbed dose in the case of accidental exposure to high radiation in a radiation facility or during a radiological accident.

Experimental setup to measure thermal waves generated by X-ray absorption using pyroelectric sensor

Pyroelectric detectors are widely used for infrared radiation detection, whereas these can also be used in the X-ray region. They have multiple advantages when used at synchrotron radiation sources, such as (a) can be used with a white beam (high flux), (b) have a flat spectral response, and (c) can be used both as a detector and as a sample. However, when used in the hard X-ray region, absorption in the detector plays an important role depending upon the thickness of the detector. Hence, the estimation of the responsivity of the detector is important. In this paper, we report an improved experimental setup for the measurement of a pyroelectric signal in the hard X-ray region. The responsivity (V/W) of a pyroelectric detector for absorbed radiation in the hard x-ray region is measured. Measurements of the K-edge x-ray absorption fine structure of 10-μm copper and nickel foils are carried out using a LiTaO₃ pyroelectric detector and compared with the measurements carried out using an ionization chamber as a sensor for the same foils. Absorption spectra near the Ta L_III and L_II edges in LiTaO₃, measured using a LiTaO₃ crystal both as a sample and as a sensor, are also reported in this paper.

Abstract WP72: Recurrent Cerebral Ischemic Events in Symptomatic Carotid Stenosis are Related to Plaque Inflammation

Background and Aims: Severity of symptomatic carotid stenosis often determines the treatment approach. However, severity explains only the regional hypoperfusion as the mechanism of cerebral ischemia. Artery-to-artery embolisation remains an important pathogenic mechanism in patients with high-risk carotid plaques. Inflammation is considered as the initiating event for plaque rupture and cerebral embolism. Using 18F-fluorodeoxyglucose positron-emission tomography (FDG-PET)/computed tomography (CT) and high-resolution magnetic resonance imaging (HR-MRI), we investigated the role of plaque imaging in stroke recurrence in our patients with recently symptomatic carotid stenosis.

Methods: This prospective study included consecutive patients within 30-days of recent stroke and ipsilateral carotid stenosis (≥50%). FDG uptake was quantified as mean standardized uptake values (SUV, g/ml). The ratio of T1 hyperintensity of carotid plaque to the ipsilateral sternocleidomastoid muscle (SCM) was recorded on T1-weighted fat suppressed HR-MRI. Patients were followed-up for stroke recurrence within 90-days.

Results: Of the 115 patients included in the study, 17 (15%) suffered from recurrent cerebral ischemic event in the stenosed carotid territory within 90-days. Compared to patients who remained asymptomatic, patients with recurrent cerebral ischemia showed higher mean T1 carotid-SCM ratio (2.19 versus 1.38; p<0.0001) and higher mean SUV value in the carotid plaque (3.04g/ml versus 1.25g/ml; p<0.0001). Higher T1 carotid-SCM ratio on HR-MRI (OR 3.215, 95%CI 1.304-5.927; p<0.0001) and higher mean SUV on FDG-PET (OR 3.601, 95%CI 2.924-7.628; p=0.005) were independent predictors of recurrent cerebral ischemia.

Conclusions: FDG-PET/CT and HR-MRI of carotid stenosis are useful tools for risk stratification and may aid in better therapeutic decision-making.

Rationale and design of a randomized trial of early intensive blood pressure lowering on cerebral perfusion parameters in thrombolysed acute ischemic stroke patients

BACKGROUND AND RATIONALE

Uncertainty persists over the optimal management of blood pressure (BP) in the early phase of acute ischemic stroke (AIS). This study aims to determine the safety and effects of intensive BP lowering on cerebral blood flow (CBF) and functional in AIS patients treated with intravenous thrombolysis.

METHODS

In a randomized controlled trial, 54 thrombolysed AIS patients with a systolic BP of 160 to 180 mm Hg will be randomized to early intensive BP lowering (systolic target range 140-160 mm Hg) or guideline-based BP management (systolic range 160-180 mm Hg) during first 72-hours using primarily intravenous labetalol. We hypothesize that early intensive BP lowering will not reduce CBF by 20% and/or increase the volume of hypoperfused tissue by >20% on computed tomographic perfusion. Clinical outcome will be assessed using a dichotomized modified Rankin scale (scores 0-1 as excellent outcome vs scores 2-6 as dead or dependent) at 90 days. Other outcome would be symptomatic intracerebral hemorrhage. The trial is registered at ClinicalTrials.gov, NCT03443596.

CONCLUSION

This randomized study will provide important information about the physiological effects of BP reduction on cerebral perfusion after intravenous thrombolysis in AIS.

Free radical scavenging potential of sericin obtained from various ecoraces of tasar cocoons and its cosmeceuticals implication

Tropical tasar silkworm Antheraea mylitta is a wild sericigenous insect which is distributed in different geographical regions and named as different ecoraces. In the present study, we investigated the molecular characterisation and cosmeceutical properties of sericin extracted from different ecoraces of tasar cocoons. The surface morphology and molecular weight of cocoons were determined by scanning electron microscope (SEM) and SDS-PAGE, respectively. Characterisation of sericin was performed by various methods such as FTIR, CHNS, TGA and amino acid analyzer. The anti-tyrosinase, anti-elastase, glutathione-S-transferase inhibition, free radical scavenging potential and inhibition of oxidative damages were measured in tasar ecoraces sericin. SEM images have revealed the removal of sericin from the surface of cocoons. SDS-PAGE of sericin depicted the presence of diverse molecular weight of proteins. Structural determination by FTIR revealed the presence of both α-helical and β-sheet structures. Thermal properties of sericin were studied by TGA which showed a 50% weight loss at temperature 410 °C-430 °C. Additionally, ecoraces sericin contains 17 amino acids in which serine, aspartic acid and glycine are predominantly present (55.68-59.61%). Further, anti-tyrosinase, anti-elastase, inhibition of glutathione-S-transferase activity, free radical scavenging potential and inhibition of lipid peroxidation were also observed in ecoraces sericin. Our findings suggest that the present study appear to be helpful in exploiting sericin as potential biomaterial in cosmeceutical and allied field.

Tasar silk fiber waste sericin: New source for anti-elastase, anti-tyrosinase and anti-oxidant compounds

The present study investigates the properties of sericin extracted from tasar silk fiber waste (TSFW). The surface morphology of TSFW was observed by scanning electron microscope (SEM). SEM images revealed the removal of residual sericin over the surface of TSFW. The molecular weight distribution of sericin was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results suggested that TSFW sericin represented a family of proteins with wide-ranging molecular weight distribution (11-245 kDa). Structural determination by FTIR revealed the presence of both α-helical and β-sheet structures. The colour was studied by colorimeter indicating less brightness, more red and yellow colour intensities. The carbon: nitrogen ratio (C:N) was studied by CHNS element analyzer and the ratio is 5.15-7.85. Thermal properties of TSFW sericin have been studied by thermogravimetric analysis (TGA) method. TGA curve showed higher thermal stability and variable degradation profiles. Furthermore, TSFW sericin contains 17 amino acids where serine, aspartic acid and glycine are the more significant compounds (54.34-60.49%). In addition, sericin was found to inhibit tyrosinase, elastase and glutathione-S-transferase activity, and had apparent radical scavenging impacts on 2.2‑diphenyl‑1‑picryl‑hydrazil (DPPH), hydrogen peroxide and inhibition of lipid peroxidation. Result suggested that TSFW sericins might be a valuable ingredient for cosmoceutical products.

Abstract 147: Plaque Inflammation is Associated With Early Cerebral Ischemic Events in Symptomatic Carotid Stenosis

Background and aims: Currently, the severity of the symptomatic carotid stenosis determines the treatment approach. However, it explains only the regional hypoperfusion as the mechanism of cerebral ischemia. Artery-to-artery embolisation remains an important pathogenic mechanism in patients with high-risk carotid plaques. Recently, inflammation has been proposed as the initiating event for plaque rupture and cerebral embolism. Using 18F-fluorodeoxyglucose positron-emission tomography (FDG-PET)/computed tomography (CT) and high resolution magnetic resonance imaging (HR-MRI), we investigated the role of plaque imaging and stroke recurrence in our cohort of patients with recently symptomatic carotid stenosis.

Methods: This ongoing prospective study included consecutive patients within 30-days of recent stroke and ipsilateral carotid stenosis (≥50%). FDG uptake was quantified as mean standardized uptake values (SUV, g/ml). The ratio of T1 hyperintensity of carotid plaque to the ipsilateral sternocleidomastoid muscle (SCM) was recorded on T1-weighted fat suppressed HR-MRI. Patients were followed prospectively for stroke recurrence within 90-days.

Results: Of the 70 patients included in the study, 11 (16%) suffered from recurrent cerebral ischemic event in the same vascular territory within 90-days. Compared to patients without subsequent cerebral ischemic events, patients with recurrent cerebral ischemia showed higher mean T1 carotid-SCM ratio (2.24 versus 1.46; p<0.0001) and higher mean SUV value in the carotid plaque (3.26g/ml versus 1.28g/ml; p<0.0001). Higher T1 carotid-SCM ratio on HR-MRI (OR 3.374, 95%CI 1.561-6.253; p<0.0001), higher mean SUV on FDG-PET (OR 3.646, 95%CI 3.172-11.524; p=0.005) were independent predictors of recurrent cerebral ischemia.

Conclusions: FDG-PET/CT and HR-MRI of carotid stenosis helps in identification of patients at higher risk of subsequent cerebral ischemic events and may aid in better therapeutic decision-making.

Long-term survival outcomes of triple-receptor negative breast cancer survivors who are disease free at 5 years and relationship with low hormone receptor positivity

Background:

We counsel our triple-negative breast cancer (TNBC) patients that the risk of recurrence is highest in the first 5 years after diagnosis. However, there are limited data with extended follow-up on the frequency, characteristics, and predictors of late events.

Methods:

We queried the MD Anderson Breast Cancer Management System database to identify patients with stage I–III TNBC who were disease free at 5 years from diagnosis. The Kaplan–Meier method was used to estimate yearly recurrence-free interval (RFI), recurrence-free survival (RFS), and distant relapse-free survival (DRFS), as defined by the STEEP criteria. Cox proportional hazards model was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs).

Results:

We identified 873 patients who were disease free at least 5 years from diagnosis with median follow-up of 8.3 years. The 10-year RFI was 97%, RFS 91%, and DRFS 92% the 15-year RFI was 95%, RFS 83%, and DRFS 84%. On a subset of patients with oestrogen receptor and progesterone receptor percentage recorded, low hormone receptor positivity conferred higher risk of late events on multivariable analysis for RFS only (RFI: HR=1.98, 95% CI=0.70–5.62, P-value=0.200; RFS: HR=1.94, 95% CI=1.05–3.56, P-value=0.034; DRFS: HR=1.72, 95% CI=0.92–3.24, P-value=0.091).

Conclusions:

The TNBC survivors who have been disease free for 5 years have a low probability of experiencing recurrence over the subsequent 10 years. Patients with low hormone receptor-positive cancers may have a higher risk of late events as measured by RFS but not by RFI or DRFS.

Giant Rashba effect at the topological surface of PrGe revealing antiferromagnetic spintronics

Rashba spin-orbit splitting in the magnetic materials opens up a new perspective in the field of spintronics. Here, we report a giant Rashba spin-orbit splitting on the PrGe [010] surface in the paramagnetic phase with Rashba coefficient α R  = 5 eVÅ. We find that α R can be tuned in this system as a function of temperature at different magnetic phases. Rashba type spin polarized surface states originates due to the strong hybridization between Pr 4f states with the conduction electrons. Significant changes observed in the spin polarized surface states across the magnetic transitions are due to the competition between Dzyaloshinsky-Moriya interaction and exchange interaction present in this system. Presence of Dzyaloshinsky-Moriya interaction on the topological surface give rise to Saddle point singularity which leads to electron-like and hole-like Rashba spin split bands in the [Formula: see text] and [Formula: see text] directions, respectively. Supporting evidences of Dzyaloshinsky-Moriya interaction have been obtained as anisotropic magnetoresistance with respect to field direction and first-order type hysteresis in the X-ray diffraction measurements. A giant negative magnetoresistance of 43% in the antiferromagnetic phase and tunable Rashba parameter with temperature makes this material a suitable candidate for application in the antiferromagnetic spintronic devices.

Grading, staging and Nottingham prognostic index scoring of breast carcinoma

Background: Breast carcinoma is the most frequent malignant tumor in women accounting for approximately 15% of female cancer deaths. It is the second most common malignancy among women in Nepal. Our objectives were to study the extent and spread of different histological types breast carcinoma in the eastern region of Nepal, to grade and stage the tumors, score the prognosis.Materials and Methods: A cross-sectional descriptive study of mastectomy specimens with axillary lymph node sampling was done for a period of two years. Diagnosis was done using WHO classification. Modified Bloom Richardson score and TNM system was used to grade and stage the tumors. Nottingham Prognostic index was applied to score the prognosis.Results: Out of 31 total cases, the most common histologic type was Invasive Carcinoma of No Special Type (67.74%). The largest tumor size was of 12cm which had poor NPI score. Most tumors were of grade II and T2. Out of 30 cases with lymph nodes, 13 were negative for metastasis pN0, 10 were pN1 and 7 were pN2. Extranodal spread was observed in 6 out of 17 cases with lymph node metastasis and was associated with higher grades and poor prognosis.Conclusion: Higher grade tumors, lymph node metastasis and extranodal extension are associated with higher Nottingham Prognostic Index score. 

Abstract TMP119: Early Cerebral Ischemic Events in Symptomatic Carotid Stenosis are Related to Plaque Inflammation

Background and aims: Symptomatic carotid stenosis is associated with an increased risk of early stroke recurrence. Severity of the stenosis, current basis of revascularization, explains only the cerebral ischemic mechanism of regional hypoperfusion. Plaque inflammation, the initiating event for plaque rupture and thromboembolism (artery-to-artery embolism), is not evaluated routinely. Using 18F-fluorodeoxyglucose positron-emission tomography (FDG-PET)/computed tomography (CT) and high resolution magnetic resonance imaging (HR-MRI), we investigated the role of plaque imaging and stroke recurrence in our cohort of stroke patients with recently symptomatic carotid stenosis.

Methods: This ongoing prospective study included consecutive patients within 30-days of recent stroke and ipsilateral carotid stenosis (≥50%). FDG uptake was quantified as mean standardized uptake values (SUV, g/ml). The ratio of T1 hyperintensity of carotid plaque to the ipsilateral sternocleidomastoid muscle (SCM) was recorded on T1-weighted fat suppressed images. Patients were followed prospectively for stroke recurrence within 90-days. Embolic potential of carotid plaque is estimated by presence of spontaneous microembolic signals (MES) on extended transcranial Doppler monitoring of ipsilateral middle cerebral artery.

Results: Of the 33 patients included in the study, 6 (18%) suffered from recurrent cerebral ischemic event in the same vascular territory within 90-days. Compared to patients without subsequent cerebral ischemic events, patients with recurrent cerebral ischemia showed higher mean T1 carotid-SCM ratio (2.49 versus 1.53; p<0.0001) and higher mean SUV value in the carotid plaque (3.52g/ml versus 1.51g/ml; p<0.0001). Higher T1 carotid-SCM ratio on HR-MRI (OR 4.249, 95%CI 1.818-5.18; p<0.0001), higher mean SUV on FDG-PET (OR 3.050, 95%CI 5.586-28.571; p=0.005) and MES on TCD (OR 2.186, 95%CI 1.652-47.619;p=0.037) were independent predictors of recurrent cerebral ischemia.

Conclusions: FDG-PET/CT and HR-MRI imaging of carotid stenosis helps in identification of patients at higher risk of subsequent cerebral ischemic events and may aid in better therapeutic decision-making.

Abstract TP443: Early Cognitive Decline in Patients with Symptomatic Carotid Stenosis is Related to Plaque Inflammation and Concomitant Intracranial Stenosis

Background and aims: Symptomatic carotid stenosis is associated with an increased risk of early stroke recurrence. Post-stroke vascular cognitive impairment is highly prevalent with significant functional consequences. However, reliable biomarkers for early prediction of cognitive decline are not well established. We postulated that regional hypoperfusion due to carotid stenosis would impair cognitive performance. Hence, we evaluated the cognitive parameters at baseline and their natural course during 90-days of follow up.

Methods: This ongoing prospective study included consecutive patients within 30-days of recent stroke and ipsilateral carotid stenosis (≥50%). Data regarding demographics and vascular risk factors were recorded. Cognitive parameters were assessed with the 30-point mini-mental scale (MMSE) and Montreal Cognitive Assessment (MoCA). All patients underwent carotid duplex sonography and 18-fluorodeoxyglucose (FDG) Positron Emission Tomography (PET) of carotid arteries. Embolic potential of the carotid plaque is estimated by presence of spontaneous microembolic signals (MES) on extended transcranial Doppler monitoring of the middle cerebral arteries. Patients are followed prospectively for change in cognitive parameters.

Results: Of the 33 patients included in this study, 7 (21%) demonstrated deterioration of their cognitive parameters (MMSE in 4, MOCA in 5 and both in 6) during 90-day follow up. Only high Standard Uptake Value (SUV) on PET (3.62g/ml in cognitive-deterioration group versus 1.72g/ml in the unaffected group; p=0.01) and presence of concomitant intracranial stenosis (p=0.01) were associated with cognitive deterioration. Of the 7 cases who underwent carotid revascularization, 5 (71%) demonstrated improved cognitive performance at day-90.

Conclusions: Early cognitive decline is common among patients with symptomatic stenosis of the extracranial carotid artery, especially when associated with concomitant intracranial stenosis and plaque inflammation.

Comparison of semen analysis by manual and automated method

Background: Semen analysis is used to evaluate male fertility. The aim of this study was to compare the results of semen analysis using manual method and automated sperm analyzer.Materials and Methods: This was a comparative study of 50 cases of semen analysis done in the Department of Pathology at the B.P. Koirala Institute of Health Sciences from March 2009 to March 2010. The automated sperm analyzer did not show the WHO parameters of patients who had functional sperm count (FSC) less than five hundred thousand (500,000). Semen analysis of each of the case included in the study was done by manual and automated method (using SQAII-P analyzer).Results: Out of 31 patients, the mean age of the patients was 28.56 years with youngest patient of 20 years and eldest of 45 year. Sensitivity and specificity was 100% in analysis of sperm concentration by both the methods. Sperm motility analysis showed 100% sensitivity and 81.81% specificity. Sperm morphology analysis showed 100% sensitivity and 34.48% specificity.Conclusion: It was observed that the automated method is much quicker and precise than the conventional, manual method for semen analysis.

Externally limited defect generation in multiwalled carbon nanotubes upon thermal annealing, and possible mechanism

Structural defects in multiwalled carbon nanotubes (MWCNTs) are found to increase upon moderate thermal annealing below 1400 K in an argon atmosphere. The defects are estimated using the ID/IG ratio in Raman spectroscopy of MWCNTs and confirmed by a direct observation using high-resolution transmission electron microscopy (HRTEM). HRTEM shows that the structural defects are created due to large damage to the outer walls of the nanotubes, while inner walls do not sustain any damage. The generation of defects on MWCNTs is attibuted to mechanical abrasion between the MWCNTs in contact, augmented by the momentum transfer from the flow of hot gas. A possible mechanism is proposed and experimentally validated by means of modulating the chemical environment of annealing from argon to hydrogen.

Structural analysis of lead magnesium niobate using synchrotron powder X-ray diffraction and the Rietveld method

The room-temperature synchrotron powder X-ray diffraction pattern of the single phase perovskite lead magnesium niobate (PMN) has shown significant broadening in the q range ∼ 5-7 Å(-1) compared with standard LaB6 synchrotron powder X-ray diffraction data, taken under similar conditions. This broadening/asymmetry lies mainly towards the lower 2θ side of the Bragg peaks. Attempts to fit this data with the paraelectric cubic phase (Pm\bar 3m) and the local rhombohedral phase (R3m) corresponding to polar nanoregions (PNRs) are made using the Rietveld method. Rietveld refinements show that neither cubic (Pm\bar 3m) nor rhombohedral (R3m) symmetry can fit this XRD pattern satisfactorily. The two-phase refinement fits the experimental data satisfactorily and suggests that the weight percentage of the PNRs is approximately 12-16% at room temperature. The unit-cell volume of these rhombohedral PNRs is approximately 0.15% larger than that of the unit cell volume of the paraelectric cubic phase.

Mask-less deposition of Au-SnO2 nanocomposites on CMOS MEMS platform for ethanol detection

Here we report on the mask-less deposition of Au-SnO2 nanocomposites with a silicon-on-insulator (SOI) complementary metal oxide semiconductor (CMOS) micro electro mechanical system (MEMS) platform through the use of dip pen nanolithography (DPN) to create a low-cost ethanol sensor. MEMS technology is used in order to achieve low power consumption, by the employment of a membrane structure formed using deep reactive ion etching technique. The device consists of an embedded tungsten micro-heater with gold interdigitated electrodes on top of the SOI membrane. The tungsten micro-heater is used to raise the membrane temperature up to its operating temperature and the electrodes are used to measure the resistance of the nanocomposite sensing layer. The CMOS MEMS devices have high electro-thermal efficiency, with 8.2 °C temperature increase per mW power of consumption. The sensing material (Au-SnO2 nanocomposite) was synthesised starting from SnO nanoplates, then Au nanoparticles were attached chemically to the surface of SnO nanoplates, finally the mixture was heated at 700 °C in an oven in air for 4 h. This composite material was sonicated for 2 h in terpineol to make a viscous homogeneous slurry and then 'written' directly across the electrode area using the DPN technique without any mask. The devices were characterised by exposure to ethanol vapour in humid air in the concentration range of 100-1000 ppm. The sensitivity varied from 1.2 to 0.27 ppm(-1) for 100-1000 ppm of ethanol at 10% relative humid air. Selectivity measurements showed that the sensors were selective towards ethanol when they were exposed to acetone and toluene.

A clinico-histopathological study on skin appendageal tumors

Background: Skin Appendageal tumors are a large and diverse group of tumors that are commonly classified according to their state of appendageal differentiation: follicular, sebaceous, eccrine and apocrine. Objectives of this study were to study the clinic-epidemiological profile of skin appendageal tumors and to correlate the clinico-histopathological diagnosis.Materials and Methods: This was a retrospective and prospective study which included all cases of skin adnexal tumours diagnosed histologically during the period of f

Microvessel density in Prostatic Lesions : Relevance to prognosis

Background:  Angiogenesis is required for growth and metastasis of tumor tissue. Quantization of angiogenesis by calculating the microvessel density can be done in histopathology specimens with the help of immunochemistry. In this study we used anti CD 34 antibody to highlight the endothelial cells and thus calculate microvessel density. Most studies have shown a positive correlation of microvessel density with increasing pathological grade and have also shown microvessel density as an independent predictor of cancer progression and survival. The present study was to find out the microvessel density in benign and malignant lesions of prostate and also to correlate the vascularity with increasing grade of cancer.Materials and methods:  Sixty five prostatic biopsies were evaluated for microvessel density using CD34 monoclonal antibody. Comparison was done between BPH and Carcinoma Prostate. MVD was correlated with Gleason’s score, weight of specimen and increasing age of patient. Effect of prostatitis on Microvessel density was studied.Results: Microvessel density was significantly higher in carcinoma prostate than in Benign Prostatic Hyperplasia. There was positive correlation of Microvessel density with increasing Gleason’s score. Microvessel was significantly increased in patients having symptoms for more than a year and also with biopsies revealing prostatitis. However, there was no significant correlation between Microvessel density and weight of specimen or increasing age.Conclusion: Since Microvessel density was found to be significantly higher in Prostatic Carcinoma and it showed positive correlation with Gleason’s score it can be added as one of the indicators for predicting the disease outcome. 

Abstract WP125: Plaque Inflammation Imaging in Carotid Stenosis and Recurrent Cerebral Ischemia

Background and aims: Symptomatic carotid stenosis is associated with an increased risk of early stroke recurrence. Currently, therapeutic decisions are largely based on the luminal narrowing, which mainly explain the cerebral ischemia related to regional hypoperfusion. Plaque inflammation, the initiating event for plaque rupture and thromboembolism (artery-to-artery embolism), is not evaluated routinely in patients with carotid stenosis. Using combined 18F-fluorodeoxyglucose positron-emission tomography (FDG-PET)/computed tomography (CT), we investigated the role of plaque inflammation and stroke recurrence in our cohort of stroke patients with recently symptomatic carotid stenosis.

Methods: This ongoing prospective study aims to include consecutive patients within 30-days of recent stroke and ipsilateral carotid stenosis (≥50%). FDG uptake is quantified as mean standardized uptake values (SUV, g/ml). Patients are followed prospectively for stroke recurrence. Embolic potential of the carotid plaque is estimated by presence of spontaneous microembolic signals (MES) on continuous transcranial Doppler monitoring of the middle cerebral arteries (MCA) for 40 minutes.

Results: Of the 22 patients included in the study, 5 suffered from recurrent cerebral ischemic event in the same vascular territory within 90 days. In patients with recurrent cerebral ischemia, the mean SUV value in the carotid plaque on the side of symptomatic carotid stenosis was higher (3.46g/ml) as compared to the patients without stroke recurrence (1.72g/ml; p=0.03). MES were noted in 3/5 cases with recurrent cerebral ischemia as compared to 2/17 cases (p=0.001)

Conclusions: FDG-PET/CT aids in the imaging of plaque inflammation and identification of patients with higher risk of subsequent cerebral ischemic events. This ongoing study intends to develop a robust prediction model for risk stratification based on luminal stenosis and plaque characteristics for better therapeutic decision-making.

Abstract WMP110: Improvement in Cortical Versus Subcortical Perfusion After Superficial Temporal Artery- Middle Cerebral Artery (MCA) Bypass in Patients With Severe Stenosis of Intracranial Carotid and MCA

Background and Objective: The role of superficial temporal artery-middle cerebral artery (STA-MCA) bypass in patients with symptomatic intracranial steno-occlusive disease has been evaluated scarcely. We have recently reported the improvement in clinical and various cerebral hemodynamic parameters after STA-MCA bypass surgery for severe steno-occlusive disease of intracranial internal carotid (ICA) or middle cerebral artery (MCA) and impaired cerebral vasodilatory reserve (CVR). Using acetazolamide challenged hexamethylpropyleneamine-oxime single-photon emission computed tomography (HMPAO-SPECT), we evaluated the differential improvement in metabolic perfusion in cortical and subcortical structures after STA-MCA bypass surgery.

Methods: Patients with severe steno-occlusive disease of intracranial ICA or MCA underwent transcranial Doppler (TCD) for CVR assessment using breath-holding index (BHI). Patients with impaired BHI (<0.69) were further evaluated with acetazolamide-challenged SPECT and STA-MCA bypass surgery was offered to patients with impaired CVR on SPECT. All patients underwent SPECT at 4±1 months. Using automated image analyzer, we evaluated differences in metabolic perfusion in cortical and subcortical regions.

Results: Of the 126 patients (80 male, mean age 56yrs; range 23-78yrs) that fulfilled our inclusion criteria, 84 (67%) showed impaired CVR on SPECT. Fifty (60%) of them underwent STA-MCA bypass surgery. HMPAO-SPECT repeated 4±1 months after surgery showed significant improvement in all cases. Significantly better improvement (14.5%) in cerebral perfusion was noted in the cortical regions as compared to the subcortical regions (4.5%, p<0.005).

Conclusion: STA-MCA bypass surgery in carefully selected patients with symptomatic severe intracranial steno-occlusive disease results in significant improvement in cerebral perfusion, especially in the cortical regions.

Study of the microstructure information of GaAs epilayers grown on silicon substrate using synchrotron radiation

Williamson-Hall (WH) analysis is a well established method for studying the microstructural properties of epilayers grown on foreign substrates. However, the method becomes inapplicable in specific cases where the structure factor considerations and the presence of anti-phase domains forbid the data acquisition for certain reflections in conventional high-resolution X-ray diffraction (HRXRD) measurements. Here, this limitation is overcome by exploiting the large intensity (25 µW mm(-2)) and high photon energy (15.5 keV) of the X-ray beam obtained from a synchrotron radiation source. The lateral coherence length, vertical coherence length, tilt and micro-strain of GaAs epilayers grown on Si substrate have been successfully measured using the conventional WH analysis. The microstructure information obtained from the conventional WH analysis based on the data acquired at the synchrotron radiation source is in reasonable agreement with the results obtained from atomic force microscope and surface profiler measurements. Such information cannot be obtained on a laboratory-based HRXRD system where modification of the WH method by involving a set of parallel asymmetric crystallographic planes is found to be essential. However, the information obtained from the modified WH method is along a different crystallographic orientation.

Impact of Image Reconstruction Settings on Texture Features in 18F-FDG PET

Evaluation of tumor heterogeneity based on texture parameters has recently attracted much interest in the PET imaging community. However, the impact of reconstruction settings on texture parameters is unclear, especially relating to time-of-flight and point-spread function modeling. Their effects on 55 texture features (TFs) and 6 features based on first-order statistics (FOS) were investigated. Standardized uptake value (SUV) measures were also evaluated as peak SUV (SUVpeak), maximum SUV, and mean SUV (SUVmean).

METHODS

This study retrospectively recruited 20 patients with lesions in the lung who underwent whole-body (18)F-FDG PET/CT. The coefficient of variation (COV) of each feature across different reconstructions was calculated.

RESULTS

SUVpeak, SUVmean, 18 TFs, and 1 FOS were the most robust (COV ≤ 5%) whereas skewness, cluster shade, and zone percentage were the least robust (COV > 20%) with respect to reconstruction algorithms using default settings. Heterogeneity parameters had different sensitivities to iteration number. Twenty-four parameters including SUVpeak and SUVmean exhibited variation with a COV less than 5%; 28 parameters, including maximum SUV, showed variation with a COV in the range of 5%-10%. In addition, skewness, cluster shade, and zone percentage were the most sensitive to iteration number. In terms of sensitivity to full width at half maximum (FWHM), 15 TFs and 1 FOS had the best performance with a COV less than 5%, whereas SUVpeak and SUVmean had a COV between 5% and 10%. Grid size had the largest impact on image features, which was demonstrated by only 11 features, including SUVpeak and SUVmean, having a COV less than 10%.

CONCLUSION

Different image features have different sensitivities to reconstruction settings. Iteration number and FWHM of the gaussian filter have a similar impact on the image features. Grid size has a larger impact on the features than iteration number and FWHM. The features that exhibited large variations such as skewness in FOS, cluster shade, and zone percentage should be used with caution. The entropy in FOS, difference entropy, inverse difference normalized, inverse difference moment normalized, low gray-level run emphasis, high gray-level run emphasis, and low gray-level zone emphasis are the most robust features.

Improvement in cerebral hemodynamic parameters and outcomes after superficial temporal artery-middle cerebral artery bypass in patients with severe stenoocclusive disease of the intracranial internal carotid or middle cerebral arteries

OBJECT

Both the older and the recent extracranial-intracranial (EC-IC) bypass trials for symptomatic carotid occlusion failed to demonstrate a reduction in stroke recurrence. However, the role of superficial temporal artery (STA)-middle cerebral artery (MCA) bypass in patients with symptomatic intracranial stenoocclusive disease has been rarely evaluated. The authors evaluated serial changes in various cerebral hemodynamic parameters in patients with severe stenoocclusive disease of the intracranial internal carotid artery (ICA) or middle cerebral artery (MCA) and impaired cerebral vasodilatory reserve (CVR), treated by STA-MCA bypass surgery or medical treatment.

METHODS

Patients with severe stenoocclusive disease of the intracranial ICA or MCA underwent transcranial Doppler (TCD) ultrasonography and CVR assessment using the breath-holding index (BHI). Patients with impaired BHI (< 0.69) were further evaluated with acetazolamide-challenge technitium-99m hexamethylpropyleneamine oxime ((99m)Tc HMPAO) SPECT. STA-MCA bypass surgery was offered to patients with impaired CVR on SPECT. All patients underwent TCD and SPECT at 4 ± 1 months and were followed up for cerebral ischemic events.

RESULTS

A total of 112 patients were included. This total included 73 men, and the mean age of the entire study population was 56 years (range 23-78 years). (99m)Tc HMPAO SPECT demonstrated impaired CVR in 77 patients (69%). Of these 77 patients, 46 underwent STA-MCA bypass while 31 received best medical treatment. TCD and acetazolamide-challenge (99m)Tc HMPAO SPECT repeated at 4 ± 1 months showed significant improvement in the STA-MCA bypass group. During a mean follow-up of 34 months (range 18-39 months), only 6 (13%) of 46 patients in the bypass group developed cerebral ischemic events, as compared with 14 (45%) of 31 patients receiving medical therapy (absolute risk reduction 32%, p = 0.008).

CONCLUSIONS

STA-MCA bypass surgery in carefully selected patients with symptomatic severe intracranial stenoocclusive disease of the intracranial ICA or MCA results in significant improvement in hemodynamic parameters and reduction in stroke recurrence.

Anesthetic management of Wolff-Parkinson-White syndrome in a pregnant patient posted for emergency caesarean section

The most common arrhythmia seen during pregnancy is paroxysmal supraventricular tachycardia and Wolff-Parkinson-White syndrome accounts for majority of this in such population. The presence of pre-disposing factors may facilitate the onset of tachyarrhythmias in previously asymptomatic parturients with the WPW syndrome such as increased hemodynamic, hormonal, autonomic, and emotional changes. Therefore, meticulous monitoring is essential perioperatively. Epidural anesthesia providing added advantage of hemodynamic stability and post-operative analgesia is preferred in such pregnant patients undergoing emergency cesarean section.

Incidental Enterobius Vermicularis infestation in surgically removed appendices with a clinical diagnosis of acute appendicitis: A retrospective analysis

Background: Appendiceal parasites can cause symptoms of appendicitis. Although the symptomatology imitates acute appendicitis clinically, the true nature of disease is diagnosed through histological examination. The aim of this study is to therefore determine the prevalence of E. Vermicularis in appendicectomy specimens to relate this to acute inflammation histologically.Materials & Methods: Histological data on all appendectomy specimens with a clinical diagnosis of acute appendicitis were retrieved from the archives of department of pathology, B.P.K.I.H.S, over the period of  five years (January 2004- December 2008) and was analyzed retrospectively.Results: There were a total of 1528 patients. M:F ratio being 1.2:1.Inflamed appendix constituted for 94.24% of all cases. There were a total of six (0.39%) appendicectomy specimens  which showed presence of oxyuriasis appendix. Though all patients with oxyuriasis presented with appendicial colic only one (1) out of the six cases of oxyuriasis showed histologic evidence of inflammation. Conclusion: We conclude that enterobius does not frequently cause inflammation of appendix though it may clinically mimic acute appendicitis. Since it represents a disease curable without necessitating surgery, symptomatology awareness is stressed upon.Journal of Pathology of Nepal (2015) Vol. 5, 720-722

Transverse wobbling in ^{135}pr

A pair of transverse wobbling bands is observed in the nucleus ^{135}Pr. The wobbling is characterized by ΔI=1, E2 transitions between the bands, and a decrease in the wobbling energy confirms its transverse nature. Additionally, a transition from transverse wobbling to a three-quasiparticle band comprised of strong magnetic dipole transitions is observed. These observations conform well to results from calculations with the tilted axis cranking model and the quasiparticle rotor model.

Comparative study of glycated hemoglobin by ion exchange chromatography and affinity binding nycocard reader in type 2 diabetes mellitus

The aim of this study was to compare the level of glycated hemoglobin (HbA1c) in type 2 Diabetes Mellitus (DM) patients by two different methods namely Ion Exchange Chromatography and Affinity Binding Nycocard Reader. This is a cross-sectional study conducted on confirmed type 2 diabetes mellitus patients (n = 100) who visited Out Patients Department of the Universal College of Medical Sciences Teaching hospital, Bhairahawa, Nepal from November 2012 to March 2013. The diagnosis of diabetes mellitus was done on the basis of their fasting (164.46 ± 45.33 mg/dl) and random (187.93 ± 78.02 mg/dl) serum glucose level along with clinical history highly suggestive of type 2 DM. The HbA1c values of (7.8 ± 1.9%) and (8.0 ± 2.2%) were found in DM patients as estimated by those two different methods respectively. The highest frequency was observed in HbA1c > 8.0% indicating maximum cases were under very poor glycemic control. However, there were no significant differences observed in HbA1c value showing both methods are comparable in nature and can be used in lab for ease of estimation. The significant raised in HbA1c indicates complications associated with DM and monitoring of therapy become hard for those patients. Despite having standard reference method for HbA1c determination, the availability of report at the time of the patient visit can be made easy by using Nycocard Reader and Ion Exchange Chromatography techniques without any delay in communicating glycemic control, clinical decision-making and changes in treatment regimen.

Structural, magnetic, and dielectric studies on Gd0.7Y0.3MnO3

Structural, magnetic, specific heat, and dielectric studies were carried out on Y substituted (30 at. %) GdMnO(3) compound as a function of temperature. Anomalies occur at ~41 and 18 K, in the specific heat measurements and are ascribed to paramagnetic, to sinusoidal incommensurate antiferromagnetic transition (ICAFM) and ICAFM to commensurate antiferromagnetic transitions, respectively. Changes in the lattice parameters across these temperatures indicate magneto-elastic coupling present in the compound. However, in the dielectric measurements, an anomaly at 18 K alone is observed and is ascribed to a ferroelectric transition, giving rise to spontaneous ferroelectric ordering at low temperatures. This observation is supported by an anomaly in lattice parameters, across the transition temperature. From the frequency dependent dielectric studies, a strong coupling between Gd(3+) and Mn(3+) magnetic sublattices is inferred and Y substitution results in substantial changes in the relaxation process compared to that of GdMnO(3).

Dermcidin isoform-2 induced nullification of the effect of acetyl salicylic acid in platelet aggregation in acute myocardial infarction

The aggregation of platelets on the plaque rupture site on the coronary artery is reported to cause both acute coronary syndromes (ACS) and acute myocardial infarction (AMI). While the inhibition of platelet aggregation by acetyl salicylic acid was reported to produce beneficial effects in ACS, it failed to do in AMI. The concentration of a stress induced protein (dermcidin isoform-2) was much higher in AMI than that in ACS. Incubation of normal platelet rich plasma (PRP) with dermcidin showed one high affinity (K_d = 40 nM) and one low affinity binding sites (K_d = 333 nM). When normal PRP was incubated with 0.4 μM dermcidin, the platelets became resistant to the inhibitory effect of aspirin similar to that in the case of AMI. Incubation of PRP from AMI with dermcidin antibody restored the sensitivity of the platelets to the aspirin effect. Incubation of AMI PRP pretreated with 15 μM aspirin, a stimulator of the NO synthesis, resulted in the increased production of NO in the platelets that removed the bound dermcidin by 40% from the high affinity binding sites of AMI platelets. When the same AMI PRP was retreated with 10 μM aspirin, the aggregation of platelets was completely inhibited by NO synthesis.

Utility of prospective step sections in diagnostic skin histopathology for small biopsies

Background: Small skin biopsies have a cosmetic advantage and prospective step sections could potentially improve turnaround time without compromising diagnostic information. The study aimed to examine the use of prospective step sections of small skin biopsies and its effect on histopathological diagnosis and turnaround time. Materials and Methods: This was a hospital based cross-sectional study at Department of Pathology and Department of Dermatology, BPKIHS from June 2011- June 2012. Diagnoses /comment on three levels of prospectively taken 3mm biopsies were compared with those of 5mm biopsies taken from the same/similar lesion from 100 patients. Additional sections from 5mm biopsies were taken retrospectively. Percentage, proportion, mean, standard deviation, diagnostic sensitivity, kappa statistics and paired sample t- test were used as statistical tools. Results: Of 100 cases, 80 were diagnosed using 5mm biopsies while 73 were diagnosed using 3mm biopsies. On additional step sections of 3mm biopsies, 3 more cases were diagnosed. When compared with 5mm biopsies, the sensitivity of the 3mm biopsy rose from 90% to 93.8% after additional sections while the measure of agreement rose from 0.751 to 0.826.Mean turnaround time for prospectively sectioned 3mm biopsies was 2.56 days and that of retrospectively sectioned 5 mm biopsies was 4.64 days with their difference being statistically significant. Conclusion: A statistically significant decrease in turnaround time and an increase in sensitivity and agreement after step sections elucidates the utility of prospective step sectioned 3 mm biopsies in diagnostic skin histopathology. DOI: http://dx.doi.org/10.3126/jpn.v4i7.10298 Journal of Pathology of Nepal (2014) Vol. 4, 552-559  

Abstract T MP29: Impaired Vasodilatory Reserve on Acetazolamide-Challenged 99tc-hmpao-Spect is a Strong Predictor of Stroke Recurrence in Patients With Severe Steno-Occlusive Disease of Intracranial Carotid or Middle Cerebral Artery

Background: Intracranial stenosis carries an increased risk for cerebrovascular ischemia. In severe stenosis, cerebral autoregulation may be impaired due to inadequate cerebral vasodilatory reserve (CVR) & intracranial steal phenomenon (reversed-Robin Hood syndrome-RRHS). Identification of patients with inadequate CVR and RRHS may help in identifying high-risk patients.

Methods: In this prospective study, we included patients with symptomatic and severe stenosis of intracranial carotid (ICA) & middle cerebral artery (MCA). CVR was evaluated with transcranial Doppler (TCD) and breath-holding index (BHI) <0.69 determined inadequate CVR. RRHS was detected as transient velocity reduction in affected artery when flow increased in the reference artery. Patients with RRHS were further evaluated with acetazolamide-challenged 99Tc-HMPAO-SPECT.

Results: 126 patients (80 male, mean age 56yrs; range 23-78yrs) fulfilled our TCD criteria for inadequate CVR. HMPAO-SPECT showed impaired CVR in 84 (67%) patients. RRHS noted on TCD in 38 (45%) patients (median steal magnitude 14%; inter-quartile range, IQR 10) was confirmed by acetazolamide-challenged HMPAO-SPECT (median perfusion deficit 8%; IQR 13%) in 35 (92%) cases (sensitivity 82%, specificity 96% with positive predictive value 96%). A strong relationship between RRHS on TCD and SPECT was noted on ROC curve analysis (area under curve 0.93; 95% confidence interval 0.87-0.98;p<0.00001). Linear relationship was observed between impaired vasodilatory reserve and stroke recurrence during follow up (mean 35months; range 8 to 49months)- 56% in patients with RRHS versus 20% in patients with moderately impaired CVR versus 4% in patients with mildly impaired CVR (chi-square 18.42; df=2; p<0.001 for trend). RRHS on HMPAO-SPECT was an independent predictor of recurrent cerebral ischemic events (RR 1.9, 95%CI 1.2-4.2; p=0.03).

Conclusions: Among patients with severe intracranial stenosis, intracranial steal phenomenon is associated with high risk of cerebral ischemic events. Acetazolamide-challenged HMPAO-SPECT is reliable in the quantification of vasodilatory reserve for selecting a target group of patients for possible revascularization.

Abstract T MP26: Role of 99tc-hmpao Spect in the Assessment of Cerebral Hemodynamic Parameters After Superficial Temporal Artery- Middle Cerebral Artery Bypass in Patients With Severe Steno-Occlusive Disease of Intracranial Carotid and Middle Cerebral Artery

Background and Objective: Although superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery in patients with symptomatic carotid occlusion failed to demonstrate any benefit, its role in symptomatic intracranial steno-occlusive disease has been evaluated scarcely. We evaluated changes in hemodynamic parameters in patients with severe steno-occlusive disease of intracranial internal carotid (ICA) or middle cerebral artery (MCA) who underwent STA-MCA bypass for impaired cerebral vasodilatory reserve (CVR).

Methods: Patients with severe steno-occlusive disease of intracranial ICA or MCA underwent transcranial Doppler (TCD) evaluation and CVR assessment using breath-holding index (BHI). Patients with impaired BHI (<0.69) were further evaluated with acetazolamide-challenged 99Tc-HMPAO-SPECT. STA-MCA bypass surgery was offered to patients with impaired CVR on SPECT. TCD and SPECT were repeated in all patients at 4±1 months and they were followed-up for cerebral ischemic events.

Results: Of the 126 patients (80 male, mean age 56yrs; range 23-78yrs) that fulfilled our inclusion criteria, 84 (67%) showed impaired CVR HMPAO-SPECT. Fifty (60%) of them underwent STA-MCA bypass while 34(40%) received best medical treatment. TCD and acetazolamide-challenged HMPAO-SPECT repeated 4±1 months after surgery showed significant improvement in STA-MCA bypass group. TCD BHI improved from a median (IQR) of -0.05 to 1.1 (p<0.001). Compared to 98% patients with impaired CVR on pre-operative SPECT, only 20% showed abnormal results on post-operative imaging (p<0.001). During follow-up (mean 35 months; range 8 to 49months), only 6/50 (12%) patients in bypass group developed cerebral ischemic events as compared to15/34 (44%) cases on medical therapy (absolute risk reduction 32%, p=0.006).

Conclusion: 99Tc-HMPAO SPECT with acetazolamide challenge is a reliable tool for the assessment of cerebral vasodilatory reserve in patients with severe steno-occlusive disease of intracranial ICA or MCA. STA-MCA bypass surgery in carefully selected patients results in significant improvement in hemodynamic parameters and reduction in stroke recurrence.