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Objective Literature regarding utility of 68 Ga-DOTATATE PET/CT in insulinoma localization across various subgroups [benign/malignant/multiple endocrine neoplasia-1 (MEN-1) syndrome associated] remains scarce. In this study, the performance of 68 Ga-DOTATATE PET/CT was compared with contrast-enhanced computed tomography (CECT) and 68 Ga-NODAGA-Exendin-4 PET/CT (whenever available) in an endogenous hyperinsulinemic hypoglycemia (EHH) cohort. Design Retrospective audit. Patients EHH patients [N = 36, lesions (n) = 49, final diagnosis: benign sporadic insulinoma (BSI) (N = 20), malignant insulinoma (N = 4, n = 14), MEN-1 syndrome associated insulinoma (N = 9, n = 15), Munchausen syndrome (N = 2) and drug-induced hypoglycemia (N = 1)] having both preoperative imaging modalities (CECT and 68 Ga-DOTATATE PET/CT). Measurements Per-lesion sensitivity (Sn) and positive predictive value (PPV) for histopathological diagnosis of insulinoma. Results Sn and PPV of 68 Ga-DOTATATE PET/CT were 67.3% and 89.2%; 55% and 100%; 85.7% and 100%; and 66.7% and 77% for overall EHH, BSI, malignant, and MEN-1 syndrome associated insulinoma cohorts respectively. Despite having comparatively lower sensitivity in BSI cohort, 68 Ga-DOTATATE PET/CT localized a pancreatic tail lesion missed by other modalities. 68 Ga-DOTATATE PET/CT had comparatively higher sensitivity in malignant insulinoma than BSI cohort. 68 Ga-DOTATATE PET/CT also paved the way for successful response to 177 Lu-based peptide receptor radionuclide therapy (PRRT). In MEN-1 cases, lower PPV as compared with BSI was due to uptake in non-insulinoma pancreatic neuroendocrine tumours (Pan-NET). Conclusions 68 Ga-DOTATATE PET/CT has supplemental role in selected cases of BSI with negative and/or discordant results with CECT and 68 Ga-NODAGA-Exendin-4 PET/CT. In malignant insulinoma, 68 Ga-DOTATATE-PET/CT has an additional theranostic potential. Interference due to uptake in non-insulinoma Pan-NET in MEN-1 syndrome may hinder insulinoma localization with 68 Ga-DOTATATE-PET/CT.

The evolution of mm-wave phased array receivers (RX) to MIMO RX promises multi-beamforming and improved capacity. Although digital beamforming (DBF) provides the highest flexibility, digitization in the beam space as opposed to element space enables ADC digitization scalability with number of beams ( $\le $ 4) and spatial filtering prior to the ADC. mm-Wave MIMO arrays must also address the challenge of increased IO routing while supporting dense fill-factors with $\lambda /2$ antenna spacing. In this work, an MIMO beam-space RX array architecture with simultaneous spatial filtering and single wire frequency-domain multiplexing (FDM) is presented. The reconfigurable weighted multi-phase mixing based beam-space RX scheme achieves both: 1) multi-beam formation/spatial filtering and 2) FDM of multiple beam-space outputs, preserving full MIMO field-of-view while ensuring a single IF interface. A 28-GHz four-element RX prototype demonstrates the proposed architecture in 65-nm CMOS. The IC occupies only 3.4 mm $\times $ 3.1 mm for a four-element MIMO 28-GHz array and can form four independent beams with >400-MHz 3-dB BW and FDM on to a single IF interface. The array consumes 450 mW and achieves >27-dB beam-to-beam isolation over 150-MHz BW, while consuming 28.1 mW/stream/beam for 28 GHz. Concurrent MIMO measurements with two wireless 28-GHz beams are shown at 400 Mb/s (100 Msps, 16QAM) data rate demonstrating mm-wave MIMO operation.

Recently, mm-wave multi-in multi-out (MIMO) arrays are garnering significant attention because of their ability to form multiple spatial beams, achieving significantly higher data rates compared to traditional phased array-based approaches. Furthermore, scalable MIMO arrays can provide many other functionalities, such as full digital beamforming and per-power amplifier (PA) digital pre-distortion. In this work, an MIMO four-element TX array architecture is presented with a frequency-domain multiplexing-based single-wire interface (SWI), breaking the tradeoff between channel-to-channel isolation and single wire (SW) bandwidth (BW). The concept of harmonic-rejection mixing (HRM) is used to de-multiplex the four modulated signals simultaneously from the SW using a single passive mixer driven by a multi-phase local oscillator (LO). The two-stage harmonic recombination circuits are implemented in baseband and, hence, achieve high channel-to-channel isolation with a low power overhead. A 60-GHz four-element TX prototype demonstrates the proposed architecture in 45-nm RF silicon-on-insulator (RFSOI) CMOS. The frequency-division-multiplexed (FDM)-based SWI can support 8-GHz total intermediate frequency (IF) BW across the four channels with 30–40-dB channel-to-channel isolation. Each TX element in the array achieves 20–35-dB conversion gain and +8.8–10.9-dBm OP1dB while consuming 225 mW/element.

Background and context Glucagon-like peptide-1 receptor (GLP-1 R) based imaging has shown higher sensitivity for insulinoma localization as compared to other anatomic/functional imaging. Methodology We reviewed the published English literature for GLP-1 R targeted imaging in insulinoma in PubMed until August 2020 in accordance with PRISMA guidelines using the MeSH terms "((Exendin-4 PET/CT) OR (Exendin-4 SPECT/CT) OR (GLP-1 R imaging)) AND (Insulinoma)". An individual patient data-metanalysis (IPD-MA) was performed, and performance parameters were calculated for the histopathological diagnosis of insulinoma. Main outcome measures True-positive (TP), false-positive (FP), false-negative (FN), true-negative (TN), sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) for insulinoma localization. Results A total of 179 cases (316 lesions) from 16 publications were included for IPD-MA. For insulinoma localization, exendin-4-PET/CT (Sn & PPV: 94%) performed better than exendin-4-SPECT/CT (Sn: 63%, PPV: 94%). The Sn was lower in malignant insulinoma cases whereas the Sp was higher in cases with MEN-1 syndrome. With exendin-4-based imaging, FP uptakes in Brunner's gland, normal pancreas, and other β-cell pathologies and FN results in pancreatic tail lesions and malignancy were seen in a few patients. TN results suggested the correct diagnosis of other endogenous hyperinsulinemic hypoglycaemia (EHH) subtypes. Conclusion For insulinoma localization, exendin-4 PET/CT should be preferred over exendin-4 SPECT/CT because of higher sensitivity and specificity. FP uptakes in Brunner's gland, normal pancreas, and other β-cell pathologies and FN results in tail lesions, and malignant insulinomas are limitations. Higher specificity for insulinoma localization is particularly useful in patients with MEN-1 syndrome.

Fragmented spectrum allocations at RF and mm-Wave, increased use of carrier aggregation/MIMO and dense spectrum-reuse in wireless links has led to interest in the design of integrated wideband, high-linearity MIMO RX that provide low noise, blocker tolerance and reconfigurability across signal domains. In this paper, receive architectures for wide operating range and blocker tolerance are presented with a focus on recent developments in reconfigurable N-path receivers. Generalized sequence-mixing architectures that support reconfigurable frequency/spatial/code-domain rejection and filtering are described along with directions of research extending operation to wider bandwidths and higher frequencies.

Introduction: 177Lu-DOTATATE-based peptide receptor radionuclide therapy (PRRT) is a promising therapy for metastatic and/or inoperable pheochromocytoma and paraganglioma (PPGL). We aim to evaluate the efficacy and safety of and identify predictors of response to 177Lu-DOTATATE therapy in metastatic and/or inoperable PPGL. Methods: This retrospective study involved 15 patients of metastatic or unresectable PPGL, who received 177Lu-DOTATATE PRRT therapy. Clinical, biochemical (plasma-free normetanephrine), and radiological (anatomical and functional) responses were compared before and after the last therapy. Results: A total of 15 patients (4 PCC, 4 sPGL, 5 HNPGL, 1 PCC + sPGL, 1 HNPGL + sPGL) were included. The median duration of follow up was 27 (range: 11–62) months from the start of PRRT. Based on the RECIST (1.1) criteria, progressive disease was seen in three (20%), stable disease in eight (53%), partial response in one (7%), and minor response in three (20%) and controlled disease in 12 (80%). On linear regression analysis the presence of PGL (P= 0.044) and baseline SUVmax >21 (P < 0.0001) were significant positive predictors of early response to PRRT. Encouraging safety profiles were noted with no long term nephrotoxicity and hematotoxicity. Conclusion: 177Lu-DOTATATE therapy is an effective and safe modality of treatment for patients with metastatic/inoperable PPGL. Although it is not prudent to withhold PRRT in metastatic PPGL with baseline SUVmax < 21, baseline SUVmax >21 can be used to predict early response to PRRT.

Context Insulinoma needs accurate preoperative localization for minimally invasive surgery. Exendin-4-based imaging has shown promising results. Objective To evaluate performance parameters of exendin-4-based imaging in insulinoma localization and compare with other imaging modalities. Design Retrospective cross-sectional study. Patients We report 14 patients with endogenous hyperinsulinemic hypoglycaemia (EHH) managed at our centre; in whom, the final diagnosis was insulinoma (n = 11), Munchausen syndrome (MS) (n = 2) and inconclusive (n = 1). Retrospective reporting of CECT, 68 Ga-DOTATATE PET/CT and 68 Ga-NODAGA-exendin-4-PET/CT was done. With per-lesion analysis, performance parameters were calculated for the histopathological diagnosis of insulinoma. Main outcome measures True positive (TP), false positive (FP), false negative (FN), true negative (TN), sensitivity (Sn), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) for insulinoma localization. Results In our cohort, 12 histopathologically proven insulinoma lesions [(TP): 11 primary lesions, 1 metastasis] were detected in 11 patients, whereas two patients had MS (TN). Sn and PPV were 75% and 100%, 33.3% and 80% and 83.3% and 71.4% for CECT, 68 Ga-DOTATATE PET/CT and 68 Ga-NODAGA-exendin-4-PET/CT, respectively. With exendin-4-based imaging, FP uptake in normal pancreatic tissue and FN results in the pancreatic tail lesion was seen. In one patient, TN result suggested the correct diagnosis of MS. Conclusion 68 Ga-NODAGA-exendin-4-PET/CT has higher sensitivity than 68 Ga-DOTATATE PET/CT and CECT for insulinoma localization. FP uptake in normal pancreas and FN result in tail lesions are limitations of currently utilized exendin-4-based imaging.

Reduction in base-station deployment costs while increasing coverage has motivated Integrated Access and Backhaul (IAB) nodes in mm-wave 5G NR (Fig. 14.3.1). Similarly, high path loss due to shadowing and limited outdoor-to-indoor penetration at mm-wave has led to an interest in repeater/relays to extend 5G NR coverage [1]. Currently, halfduplexlinks based on TDD (preferred for lAB), FDD, spatial, and polarization-duplexare explored, targeting mm-wave TWRX isolation at the cost of channel capacity. While mmwave in-band full-duplex (IBFD) with shared antenna (ANT) interface can enable spectrum reuse in IAB and repeaters/relays, >100dB total self-interference cancellation (SIC) is required with up to 50dB of SIC in the mm-wave front-end [2]. Such SIC has been shown for IBFD at RF [3– 5], however mm-wave IBFD SIC with a shared antenna interface has been limited to 20dBat28GHz and 40dB(22dB at +10dBm TX SI power) at 60GHz [6, 7]. Achieving mm-wave IBFD SIC with a shared ANT interface is particularly challenging given (i) the high frequency of operation, (ii) wide 400MHz/800MHz bandwidths targeted in 5G NR, and (iii) variations in beamformer ANT impedance that changes the SI channel. This paper presents a fully integrated mm-wave circulator RX that addresses these challenges using (i) a hybrid-coupler and non-reciprocal N-path filter-based shared ANT interface that provides wideband SIC while creating an SI replica, enabling (ii) subsequent active cancellation with variable gain/phase shift to accommodate SI channel variations. The circulator RX implementation in 45nm SOI CMOS achieves 52. 8dB cancellation across 400MHz at 26. 4GHz(>100 $\times$ improvement over state of the art at high power levels) with 3.1dB TX-to-ANT insertion loss (IL) and +11.5dBm TX power-handling. System-level feasibility for mm-wave wideband IBFD is shown with the integrated RX supporting 600MS/s128-OAM wireless reception (4.2Gb/s) with 3.3% RX EVM in the presence of an in-band 128-OAM 300MS/s (limited by instrument) TX SI signal, and SIC is demonstrated across SI channel changes using a global optimization approach.

Context Preoperative blockade with α-blockers is recommended in patients with pheochromocytoma/paraganglioma (PPGL). The data on calcium channel blockade (CCB) in PPGL are scarce. Objective We aimed to compare the efficacy of CCB and α-blockers on intraoperative hemodynamic instability (HDI) in PPGL. Methods In the interim analysis of this monocentric, pilot, open-label, randomized controlled trial, patients with solitary, secretory, and nonmetastatic PPGL were randomized to oral prazosin gastrointestinal therapeutic system (GITS) (maximum 30 mg, n = 9) or amlodipine (maximum 20 mg, n = 11). The primary outcomes were the episodes and duration of hypertension (systolic blood pressure ≥ 160 mmHg) and hypotension (mean arterial pressure Results The median (IQR) episodes (2 [1-3] vs 0 [0-1]; P = 0.002) and duration of hypertension (19 [14-42] vs 0 [0-3] minutes; P = 0.001) and intraoperative HDI duration (22.85 ± 18.4% vs 2.44 ± 2.4%; CI, 8.68-32.14%; P 0.002) were significantly higher in the prazosin GITS arm than the amlodipine arm, whereas episodes and duration of hypotension did not differ between the 2 groups. There was no perioperative mortality. One patient had intraoperative ST depression on the electrocardiogram. The drug-related adverse effects were pedal edema (1 in amlodipine), dizziness (1 in prazosin GITS), and tachycardia (6 in prazosin GITS and 3 in amlodipine). Conclusion Preoperative blockade with amlodipine is an efficacious alternative to prazosin GITS in preventing intraoperative HDI in PPGL. Larger studies that compare preoperative blockade by amlodipine with other α-blockers like phenoxybenzamine and/or doxazosin in PPGL patients are warranted.

This work demonstrates a 60GHz 45nm RF-SOI 4-element scalable MIMO TX with a single-wire interface (SWI) to alleviate the challenge of supporting high data-rate I/O in a large-scale tiled MIMO mm-wave array. Frequency-domain multiplexing is used on the single wire to simultaneously support the signals of all 4 MIMO channels while breaking the trade-off between channel-to-channel isolation and single-wire bandwidth. Harmonic-rejection mixing (HRM) is used to demultiplex the 4 modulated signals simultaneously from the single-wire, each with 2GHz bandwidth (total BW of 8GHz). A novel two-stage wideband HRM achieves high channel-to-channel isolation with low power overhead. The single-wire interface can support 8GHz total IF bandwidth across the 4 channels with 30-40dB SFDR. Each TX in the array achieves 20-35dB conversion gain and 8.8-10.9dBm OP1dB while maintaining a channel-to-channel isolation >30dB. System level measurements show the ability of the MIMO chip to form multiple simultaneous independent beams carrying independent signals.

A 38-year-old female presented with recurrent episodes of hypoglycemia for 5 years. On 72-h fast test, critical sample biochemistry was suggestive of endogenous hyperinsulinemic hypoglycemia. Both constrast-enhanced computed tomography and 68Ga-DOTATATE positron emission tomography/computerized tomography (PET/CT) revealed no pancreatic lesion but showed a jejunal lesion suggestive of neuroendocrine tumor (NET) but not confirmatory of insulinoma. 68Ga-Exendin-4 PET/CT showed intense uptake in the proximal jejunum, and this being a specific scan for insulinoma, confirmed it as an ectopic insulinoma. The patient attained normoglycemia after excision of this NET confirming it to be a case of ectopic insulinoma located in the jejunum. Although most insulinomas are located in the pancreas, rarely ectopic cases have been described in the spleen, perisplenic tissue, duodenohepatic ligament, adjacent to the ligament of Treitz, duodenum, and the jejunum. Functional scanning with 68Ga-Exendin-4 PET/CT scan aids the localization of ectopic insulinoma.

Background: Preoperative blockade with α-blockers is recommended in patients with pheochromocytoma/paraganglioma (PPGL). The data on calcium channel blockade (CCB) in PPGL is scarce. We aim to compare the efficacy of CCB and α-blockers on intraoperative haemodynamic instability (HDI) in PPGL. Methods: In the interim analysis of this monocentric, pilot, open-label, randomized controlled trial, patients with solitary, secretory, and nonmetastatic PPGL were randomized to oral prazosin (maximum 30mg, n=9) or amlodipine (maximum 20mg, n=11). The primary outcomes were the episodes and duration of hypertension (SBP≥160mmHg) and hypotension (MAP

A low-power 28-GHz phased-array receiver (RX) front end is presented that incorporates a low-power low-noise amplifier (LNA) and a passive reflection-type phase shifter (RTPS) capable of 360° phase shift with 5-b phase resolution and low gain variation. Passive phase shifters are limited by tradeoffs between phase resolution, insertion loss, and phase shift range. The proposed RTPS load design and optimization approach leads to a 28-GHz RTPS achieving the state-of-the-art insertion loss with 360° phase shift range and low loss variation across the phase shift. The LNA adopts a transformer-coupled neutralization architecture that increases available gain, enabling lower power consumption. The phased-array front end is designed for Ka -band applications and has been implemented in 65-nm CMOS. The measured RTPS achieves 360° phase shift with 7.75 ± 0.3 dB insertion loss and an rms phase error of 0.3° at 28 GHz. The low-power phased-array RX front end has an overall gain of 9.5 ± 0.4 dB and noise figure

High-data-rate wireless links at mm-wave have motivated the development of scalable, dense arrays with hundreds of elements [1], [2]. The evolution from “multiple-input-single-output” phased arrays towards multibeam/MIMO arrays presents significant challenges. Firstly, increasing the number of beamforming blocks and outputs to preserve signals from every element increases IC area and makes compact on-package signal routing challenging. This limits a scalable unit-tile approach with $\lambda/2 \times\lambda$ /2 spacing. Secondly, it is important to include spatial filtering in such MIMO arrays to mitigate blockers and reduce ADC dynamic-range requirements (Fig. 4.3.1) [4]–[6]. Thirdly, traditional digital beamforming requires the full aggregate IF interface bandwidth and all ADCs to operate irrespective of the number of beams. Given dynamic operating environments, it is desirable to have array architectures that support power-scalable configurability from phased-arrays to multibeam arrays to full-field-of-view (FoV) MIMO arrays.

Background: Empathy plays an important role in healthy dentist and patient relationship. Hence, the aim of the study is to (a) to measure the self‑reported empathy levels among dental undergraduate and postgraduate students. (b) To review the trend of changes in empathy level with experience, age, and gender among dental undergraduate and postgraduate students. Materials and Methods: This cross‑sectional, questionnaire‑based study was carried out in two private dental institutions situated in Sri Ganganagar, India, with a sample size of 978. Data were obtained from the 1st to final year (BDS), interns, and postgraduate students from January to March 2015. An empathy level of students was assessed by the Jefferson Scale of Physician Empathy – Health Profession Students Version Questionnaire. An exploratory factor analysis using Kaiser’s criteria was undertaken to appraise the construct validity and dimensionality. Based on the results of the factor analysis, three factors were selected; labeled as “perspective taking,” “compassionate care,” and “standing in patient’s shoes.” Results: The majority of the students was female in a equivalent ratio of 1338:618. There were significant differences in empathy scores by gender and age ( P < 0.01). The lowest and highest mean empathy scores were found in postgraduate (mean = 108.77, standard deviation [SD] =9.12) and 1st year (mean = 117.23, SD = 14.19) dental students, respectively. Conclusion: Dental educators should consider the likely decline in empathy among students as early as possible and adopt communication teaching strategies to promote the development of empathy and reduce the risk of further decline. Key Words: Dental education, dentist, empathy, sympathy

This Letters corrects errata in the above paper [1] . The minimum rms phase error for the RTPS stand-alone [1, Table I] and for the front-end [1, Table II] computed as per the approach in [2] (with a zero average phase error) are 1.5° and 1.4°, respectively. The measured rms error of the RTPS across frequency is shown in Fig. 1 . Table I presents updated comparisons with state-of-the-art phase shifters and corrects errors in reference numbers in [1, Table I] . Comparisons with mm-wave phased array front-ends are shown in Table II . This work achieves 360° phase shift with low loss variation.

Mediastinal lymph node enlargement commonly seen in sarcoidosis, lung cancer, lymphoma and tuberculosis in children’s. Tuberculosis in adult mostly involve parenchyma of lung and very rarely involve mediastinal lymph nodes, here we report a 27-year-old male, non-diabetic, non-hypertensive, non-alcoholic and non-smoker who present with low grade fever and dry cough. Search for the cause of morbidity revealed him to be suffering from mediastinal tuberculosis. He was treated for tuberculosis with ATT.

Increased serum and mRNA levels of cytokines in patients with dengue virus (DV) infection suggest that cytokines are one of the key factors in the pathogenesis of disease caused by this virus. Here, we tested 211 serum and 56 mRNA samples from an equal number of dengue cases to determine the levels of interleukin-8 (IL-8), interferon gamma (IFN-γ), interleukin-10 (IL-10) and transforming growth factor beta (TGF-β). A total 70 serum and 15 mRNA samples from healthy individual were also tested for cytokines and served as controls. Serum and mRNA levels of IL-8 were highest in the earlier days of dengue infection. IFNγ levels peaked one or two days before defervescence. Levels of IL-10 and TGF-β were highest later in dengue infection, and TGF-β levels peaked on the day of defervescence. Mean levels of IFNγ, TGF β and IL-10 were higher in samples from dengue cases, irrespective of severity, than in healthy controls. In contrast, the level of IL-8 was significantly higher in samples from severe dengue cases and lower in cases of dengue without warning signs than in healthy controls. Children (82.2 % of 101 paediatric cases) commonly had severe dengue illness. Samples that were positive for anti-DV IgG antibody had higher levels of IL-8 and TGF β. DV-2 infections were associated with severe dengue illness. IL-8 and IFNγ levels were higher in the presence of warning signs of severe dengue. Levels of IL-8, IL-10 and TGF β were independently associated with disease outcome. These data provide evidence of an association of IL-8, IFNγ, TGF β and IL-10 levels with the severity of dengue illness. Especially, IL-8 levels can be used as a predictor of severe DV infection.

In an attempt to extend the applications of IR spectroscopy, we report here on a novel method for the determination of the tensile strength (Ts) of polybutadiene rubber (PBR). A simple linear correlation between Ts and the peak absorbance ratio was developed. The method is simple, direct, and fast and involves only the measurement of the absorbance ratio from the IR spectrum of PBR film. The results obtained by this (IR-based) method and the currently used (ASTM) method, for quality control/quality assurance purposes, were in good agreement. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2135–2139, 2001