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Goals/Purpose Patients with adjuvant radiotherapy are significantly more likely to have complications such as infections and wound dehiscence following breast surgery.1 Closed incision negative pressure wound therapy (cINPT) holds incision edges together, prevents external contamination and removes exudate, promoting tensile strength and increased collagen recruitment at the incision site compared to the standard of care dressings.2 cINPT is helpful in surgical closures on high-risk patients.3 We evaluated the complication rates following the use of cINPT in implant-based breast reconstruction. Methods/Technique A cohort was collected retrospectively from a single institution, from January 1, 2018 to October 31 2022. The complication rates were then compared between cINPT dressing and standard-of-care dressings on radiated patients following breast surgery. Results/Complications The data collected consist of a total of 83 radiated breasts that underwent implant based reconstruction. cINPT was used in 41 breasts and standard-of-care dressings were used in 42 breasts. Of the cINPT cohort, 2 patients developed seromas that required bedside aspirations (4.8%) and one patient developed an infection (2.4%) with none of the patients requiring re operations. Of the standard of care dressings cohort, 9 patients developed seromas (21.4%), and 3 patients developed infections (7.1%), of which 3 patients required reoperations (7.1%). Conclusion Patients with prior radiation who received cINPT had lower risk of developing complications compared to patients with prior radiation who received standard-of-care dressings.

Deep learning models have shown their great performances in natural language processing tasks. While much attention has been paid towards improvements in utility, privacy leakage and social bias are two major concerns arising in trained models. In this paper, we protect individual privacy and mitigate gender bias on classification models simultaneously. First, we propose a selective privacy-preserving method that only obscure individuals' sensitive information by adding noise on word embeddings. Then we propose a negative multi-task learning framework to mitigate the gender bias which contains a main task and a gender prediction task. The main task uses a positive loss constraint to ensure utility while the gender prediction task applies a negative loss constraint to remove gender-specific features. We analyze two existing word embeddings and evaluate them on sentiment analysis and medical text classification tasks. Our experimental results show that our negative multi-task learning framework can mitigate the gender bias while keeping models’ utility on both sentiment analysis and medical text classification.

Acute decompensated heart failure (ADHF) is a primary cause of older adults presenting to the emergency department with acute dyspnea. Point-of-care lung ultrasound (LUS) has shown comparable or superior diagnostic accuracy in comparison with a chest x-ray (CXR) in patients presenting with symptoms of ADHF. The systematic review and meta-analysis aimed to elucidate the sensitivity and specificity of LUS in comparison with CXR for diagnosing ADHF and summarize the rapidly growing body of evidence in this domain. A total of 5 databases were searched through February 18, 2021, to identify observational studies that reported on the use of LUS compared with CXR in diagnosing ADHF in patients presenting with shortness of breath. Meta-analysis was conducted on the sensitivities and specificities of each diagnostic method. A total of 8 studies reporting on 2,787 patients were included in this meta-analysis. For patients presenting with signs and symptoms of ADHF, LUS was found to be more sensitive than CXR (91.8% vs 76.5%) and more specific than CXR (92.3% vs 87.0%) for the detection of cardiogenic pulmonary edema. In conclusion, LUS is more sensitive and specific than CXR in detecting pulmonary edema. This highlights the importance of sonographic B-lines, along with the accurate interpretation of clinical data, in the diagnosis of ADHF. In addition to its convenience, reduced costs, and reduced radiation exposure, LUS should be considered an effective alternative to CXR for evaluating patients with dyspnea in the setting of ADHF.

Introduction/objectives: Diabetic Kidney Disease (DKD) is the leading cause of end-stage kidney disease. Despite optimal glycemic control and blood pressure management, progression to DKD cannot be halted in some patients. We aimed to find the association of modifiable and non-modifiable risk factors and comorbid conditions in patients with DKD. Methods: Retrospective medical record review of adult patients with diabetes mellitus (DM) was performed who visited our internal medicine office between January 1, 2020 and December 31, 2020. Results: Among 728 patients with DM, 471 (64.7%) patients had DKD, and 257 (35.3%) patients were without DKD. Among the group of patients with DKD, the majority were in CKD stage G1A2 (34.6%), followed equally by G2A2 and G3aA1 (16.8% each). Mean age of the patients with DKD was significantly greater than the patients without DKD (69.4 years vs 62.2 years; P Conclusions: In patients with diabetes, increasing age, female sex, and lack of moderate alcohol consumption were associated with increased odds of DKD. Higher frequencies of association of hypertension, hyperlipidemia, coronary artery disease, cerebrovascular accidents, congestive heart failure, carotid artery stenosis, aortic aneurysm, peripheral artery disease, gout, and osteoarthritis were also seen in patients with DKD.

Introduction: The purpose of this study is to produce a bibliometric review of the 30 most cited articles related to 6 major domains of body contouring—abdominoplasty, thighplasty, brachioplasty, gluteoplasty, body lift, and liposuction—for resident and fellow education. Methods: The authors utilized the Web of Science Citation Index to identify the 30 most cited articles related to surgery for body contouring published from 1975 to 2020. Articles were classified according to their level of evidence, type of study, and country of publication. Results: A total of 336 articles were reviewed to compile our list. The mean number of citations across the articles was 114.7 ± SD 86.1. The highest prevalence of the papers was published between 2000 and 2009 (n = 15, 50%). The country with the highest number of contributions was the United States (n = 22, 73%). Plastic and Reconstructive Surgery served as the main journal of publication for these papers (n = 22, 73.3%). The majority of articles were designated for clinical-type studies (n = 26, 86.7%). No basic science or prevalence study design papers were listed. In terms of level of evidence (LoE), most papers were assigned IV (n = 11, 36.7%) and III (n = 7, 23.3%). Conclusions: Our study reveals that the most cited papers in body contouring are of LoE III and IV. Although the LoE of plastic surgery research, in general, has improved, in the past decade, a call for higher quality papers remains. Overall, this analysis provides an easy, electronic starting point for residents and fellows interested in understanding the field's evolution.

This protocol details the constitution of our anesthesia cocktail that we use for sedating our mice when performing surgeries. The surgeries we typically perform are thymectomies and implantation of material under the kidney capsule (through open abdomen or minimally invasive approaches).

This protocol details the steps for isolating human CD34+ cells from human fetal liver. It also explains how to prepare human fetal thymus for immediate use or for freezing, as well as the process for thawing. The CD34+ cells are hematopoietic progenitor cells and can be used to generate humanized mice through reconstitution of immune cells via IV injection after bone marrow ablation. These cells can also be used for mixed lymphocyte reaction experiments.

This protocol details our minimally invasive approach for implanting human thymus tissue under the kidney capsule of NSG mice. In contrast to our open abdominal approach, this approach is from the dorsal aspect of the mouse and requires only two interrupted sutures and 1-2 staples to close the incision. The technique can be applied to other strains of mice, though we have found the NSG kidney capsule to be more delicate, and thus more challenging to manipulate during surgery.

This protocol details the steps for isolating CD34+ cells from human bone marrow. The CD34+ cells isolated from this protocol can be used for generating humanized mice through reconstitution of immune cells via IV injection after bone marrow ablation. These cells can also be used for mixed lymphocyte reaction experiments.

This protocol details how to create humanized mouse models from NSG mice. Four different variants of humanized mice can be generated based on whether or not the native thymus is retained or if a human thymus piece is transplanted. Which type of humanized mouse is desired depends on the goals for the experiment. See our protocols on NSG mouse thymectomy, human CD34+ cell isolation, and human fetal thymus preparation for more details on some of the steps in this protocol (“Thymectomy procedure to remove native thymus of NSG mice”, “Human CD34+ cell isolation from fetal liver, and fetal thymus preparation”, “CD34+ isolation from human bone marrow”).

This protocol details our approach to removing the native thymus from an NSG mouse. The NSG mouse thymus is atrophied, but through experiments in our lab, we have found that these thymi are still functional and capable of producing CD3+ cells. Removal of these native thymi prevents the production of CD3+ cells in NSG mice if a replacement thymus is not implanted. Due to their atrophic state, the native thymi are difficult to visualize during surgery and much practice is required to reduce mortality during the operation.

We previously published on the design and synthesis of novel, potent and selective PPARα antagonists suitable for either i.p. or oral in vivo administration for the potential treatment of cancer. Described herein is SAR for a subsequent program, where we set out to identify selective and potent PPARα/δ dual antagonist molecules. Emerging literature indicates that both PPARα and PPARδ antagonism may be helpful in curbing the proliferation of certain types of cancer. This dual antagonism could also be used to study PPARs in other settings. After testing for selective and dual potency, off-target counter screening, metabolic stability, oral bioavailability and associated toxicity, compound 11, the first reported PPARα/δ dual antagonist was chosen for more advanced preclinical evaluation.

IntroductionFamotidine is a competitive histamine H2-receptor antagonist most commonly used for gastric acid suppression but thought to have potential efficacy in treating patients with COVID-19. The aims of this systematic review and meta-analysis are to summarize the current literature and report clinical outcomes on the use of famotidine for treatment of hospitalized patients with COVID-19.MethodsFive databases were searched through February 12, 2021 to identify observational studies that reported on associations of famotidine use with outcomes in COVID-19. Meta-analysis was conducted for composite primary clinical outcome (e.g. rate of death, intubation, or intensive care unit admissions) and death separately, where either aggregate odds ratio (OR) or hazard ratio (HR) was calculated.ResultsFour studies, reporting on 46,435 total patients and 3,110 patients treated with famotidine, were included in this meta-analysis. There was no significant association between famotidine use and composite outcomes in patients with COVID-19: HR 0.63 (95% CI: 0.35, 1.16). Across the three studies that reported mortality separated from other endpoints, there was no association between famotidine use during hospitalization and risk of death - HR 0.67 (95% CI: 0.26, 1.73) and OR 0.79 (95% CI: 0.19, 3.34). Heterogeneity ranged from 83.69% to 88.07%.ConclusionBased on the existing observational studies, famotidine use is not associated with a reduced risk of mortality or combined outcome of mortality, intubation, and/or intensive care services in hospitalized individuals with COVID-19, though heterogeneity was high, and point estimates suggested a possible protective effect for the composite outcome that may not have been observed due to lack of power. Further RCTs may help determine the efficacy and safety of famotidine as a treatment for COVID-19 patients in various care settings of the disease.

Background: In preparation for a quality improvement study, we queried our prospective stroke registry for patients who might benefit from prophylactic monitoring in order to estimate the time advantage to monitoring. Methods: A prospective, single center registry of adult patients (9/20/19-6/30/20) was queried for in-hospital acute anterior circulation strokes. Indications for hospitalization as well as delays from last known well (LKW) to symptom recognition, imaging, and treatment were explored. Results: Of 540 consecutively evaluated adults with acute stroke, 68 (12.6%) developed an anterior circulation infarction while hospitalized, 32 (47.1%) of whom were female with a median age of 66 years (IQR 60-77) and median NIHSS of 14 (IQR 4-22). Four patients (5.9%) received intravenous thrombolysis although another 20 (29.4%) would have been eligible for thrombolysis if not for a delay in symptom recognition. An internal carotid, M1, or M2 occlusion was observed in 13 patients (19.1%), 8 of whom were treated at a median of 198 minutes after LKW (IQR 102-670; Figure). In patients treated endovascularly or with thrombolytics, the delay from LKW to symptom recognition accounted for 55.5% of the delay in care. Conclusions: One-third of patients in this single-center cohort would have been eligible for thrombolysis were it not for delays in symptom recognition. The delay to groin puncture exceeded 3 hours for over half of patients with proximal anterior occlusions. Earlier detection using prophylactic monitoring devices has the potential to reduce this major impedance to stroke care and ultimately improve outcomes.

The novel human coronavirus disease (COVID-19) has been associated with vascular and thrombotic complications, some of which may result from endothelial dysfunction, including the posterior reversible encephalopathy syndrome (PRES). We report a case series of 8 patients with COVID-19 and PRES diagnosed at two academic medical centers between March and July of 2020. The clinical, laboratory and radiographic data, treatment, and short-term outcomes were retrospectively analyzed. The mean age was 57.9 ± 12 years, and 50% were women. Four patients had previous vascular comorbidities. All the patients suffered from severe pneumonia, requiring intensive care unit admission. Five patients were not hypertensive at presentation (all SBP

Epilepsy incidence and prevalence peaks in older adults yet systematic studies of brain ageing and cognition in older adults with epilepsy remain limited. Here, we characterize patterns of cortical atrophy and cognitive impairment in 73 older adults with temporal lobe epilepsy (>55 years) and compare these patterns to those observed in 70 healthy controls and 79 patients with amnestic mild cognitive impairment, the prodromal stage of Alzheimer’s disease. Patients with temporal lobe epilepsy were recruited from four tertiary epilepsy surgical centres; amnestic mild cognitive impairment and control subjects were obtained from the Alzheimer’s Disease Neuroimaging Initiative database. Whole brain and region of interest analyses were conducted between patient groups and controls, as well as between temporal lobe epilepsy patients with early-onset (age of onset 50 years) seizures. Older adults with temporal lobe epilepsy demonstrated a similar pattern and magnitude of medial temporal lobe atrophy to amnestic mild cognitive impairment. Region of interest analyses revealed pronounced medial temporal lobe thinning in both patient groups in bilateral entorhinal, temporal pole, and fusiform regions (all P

A 16-element phased-array transceiver covering the entire 57-71 GHz band of the IEEE 802.11ad standard is presented. The radio is implemented in a 130-nm SiGe BiCMOS technology. The packaged die is measured and results are given for the transmitter, receiver and PLL performances. The transmitter has a peak single-element OP 1dB of 13.8 dBm, including SPDT and packaging losses. The receiver has a system noise figure between 6.3 and 7.6 dB. With all 16-elements active the transceiver consumes 9.8 W in TX mode (at P 1dB ) and 1.9 W in RX mode. Preliminary link tests showing 1.8 Gbps at over 700 m are reported.

Introduction Famotidine is a competitive histamine H2-receptor antagonist most commonly used for gastric acid suppression but thought to have potential efficacy in treating patients with Coronavirus disease 2019 (COVID-19). The aims of this systematic review and meta-analysis are to summarize the current literature and report clinical outcomes on the use of famotidine for treatment of hospitalized patients with COVID-19. Methods Five databases were searched through February 12, 2021 to identify observational studies that reported on associations of famotidine use with outcomes in COVID-19. Meta-analysis was conducted for composite primary clinical outcome (e.g. rate of death, intubation, or intensive care unit admissions) and death separately, where either aggregate odds ratio (OR) or hazard ratio (HR) was calculated. Results Four studies, reporting on 46,435 total patients and 3,110 patients treated with famotidine, were included in this meta-analysis. There was no significant association between famotidine use and composite outcomes in patients with COVID-19: HR 0.63 (95% CI: 0.35, 1.16). Across the three studies that reported mortality separated from other endpoints, there was no association between famotidine use during hospitalization and risk of death—HR 0.67 (95% CI: 0.26, 1.73) and OR 0.79 (95% CI: 0.19, 3.34). Heterogeneity ranged from 83.69% to 88.07%. Conclusion Based on the existing observational studies, famotidine use is not associated with a reduced risk of mortality or combined outcome of mortality, intubation, and/or intensive care services in hospitalized individuals with COVID-19, though heterogeneity was high, and point estimates suggested a possible protective effect for the composite outcome that may not have been observed due to lack of power. Further randomized controlled trials (RCTs) may help determine the efficacy and safety of famotidine as a treatment for COVID-19 patients in various care settings of the disease.

OBJECTIVE: To characterize differences in disposition arrangement among rehab-eligible stroke patients at a Comprehensive Stroke Center before and during the COVID-19 pandemic. MATERIALS AND METHODS: We retrospectively analyzed a prospective registry for demographics, hospital course, and discharge dispositions of rehab-eligible acute stroke survivors admitted 6 months prior to (10/2019-03/2020) and during (04/2020-09/2020) the COVID-19 pandemic. The primary outcome was discharge to an inpatient rehabilitation facility (IRF) as opposed to other facilities using descriptive statistics, and IRF versus home using unadjusted and adjusted backward stepwise logistic regression. RESULTS: Of the 507 rehab-eligible stroke survivors, there was no difference in age, premorbid disability, or stroke severity between study periods (p>0.05). There was a 9% absolute decrease in discharges to an IRF during the pandemic (32.1% vs. 41.1%, p=0.04), which translated to 38% lower odds of being discharged to IRF versus home in unadjusted regression (OR 0.62, 95%CI 0.42-0.92, p=0.016). The lower odds of discharge to IRF persisted in the multivariable model (aOR 0.16, 95%CI 0.09-0.31, p

Cerebrovascular risk factors (CVRFs) and comorbid cardiovascular and metabolic disease have been linked to accelerated cognitive aging and dementia in the general population; however, the contribution of these comorbidities to the risk of post anterior temporal lobectomy (ATL) memory decline has been unexamined. We explored the effects of CVRFs on postoperative verbal memory decline in a cohort of 22 patients with left temporal lobe epilepsy (LTLE) who completed pre- and one-year postsurgical neuropsychological testing. Diagnoses of interest included preoperative cardiovascular and metabolic disorders, as well as CVRFs [pulse pressure proxy, body mass index (BMI), and fasting glucose]. Twenty-three percent of patients had a history of cardiovascular disease, 9% of metabolic disorders, and 38% had a BMI indicating overweight or obese status. Higher preoperative BMI and glucose were associated with greater decline in verbal memory. The association between BMI and memory decline remained significant after controlling for age and left hippocampal volume. These findings suggest that modifiable health-related risk factors, including CVRFs, may impact the risk of postoperative cognitive decline, and that BMI in particular could be an important factor to consider and/or target for intervention early in clinical care to protect cognitive health.

In this study, the board level reliability (BLR) performance of different copper (Cu) post wafer level package (WLP) structures without epoxy or molding encapsulation have been evaluated and compared to standard WLP. The Cu post WLP test vehicle has been performed on different stack up structures of 4.7 x 7.1 mm2 package size at 0.4 mm ball pitch. The Cu post bumps of test vehicles were manufactured through main-stream production technologies including standard ball drop and electro-plated lead free solder after Cu post completed. The Cu post WLP will enhance the risk of board level solder joint fatigue due to thick Cu post without encapsulation will increase bump site stress. The optimized design parameters of package stack up with low temperature cured polyimide are implemented to accommodate the increased stress. In this work, we also evaluated a novel Cu post WLP stack up structure for fast package cycle time and fine pitch application. The improved BLR performance of large die size Cu post WLP is demonstrated in this investigation. The failure modes analysis and Weibull failure statistics are presented for the BLR results and recommendations as to the preferred Cu post WLP structure are also included.

Tumor-specific metabolic changes can reveal new therapeutic targets. Our findings implicate a supporting role for fatty acid metabolism in chronic lymphocytic leukemia (CLL) cell survival. Peroxisome proliferator–activated receptor (PPAR)-α, a major transcriptional regulator of fatty acid oxidation, was recently shown to be upregulated in CLL. To evaluate PPARα as a potential therapeutic target, we developed a highly selective, potent small molecule antagonist of PPARα, NXT629. NXT629 inhibited agonist-induced transcription of PPARα-regulated genes, demonstrating target engagement in CLL cells. Furthermore, NXT629 induced apoptosis of CLL cells even in the presence of a protective microenvironment. To mimic the proliferative lymphoid compartment of CLL, we examined the activity of NXT629 on CLL cells that were stimulated to proliferate in vitro. NXT629 reduced the number of leukemia cells undergoing cell division. In addition, in two xenograft mouse models of CLL (one a model for nondividing and one for dividing CLL), NXT629 reduced the number of viable CLL cells in vivo. Overall, these results suggest that fatty acid metabolism promotes survival and proliferation of primary CLL cells and that inhibiting PPARα gene regulation could be a new therapeutic approach to treating CLL.

The discovery and SAR of a novel series of potent and selective PPARα antagonists are herein described. Exploration of replacements for the labile acyl sulfonamide linker led to a biaryl sulfonamide series of which compound 33 proved to be suitable for further profiling in vivo. Compound 33 demonstrated excellent potency, selectivity against other nuclear hormone receptors, and good pharmacokinetics in mouse.

Peroxisome-proliferator activated receptors (PPAR) are members of the nuclear hormone receptor superfamily which regulate gene transcription. PPARα is a key regulator of lipid homeostasis and a negative regulator of inflammation. Under conditions of metabolic stress such as fasting or glucose deprivation, PPARα is upregulated in order to control gene expression necessary for processing alternate fuel sources (e.g. fatty acid oxidation) and thereby promote maintenance of cell viability. Clinically, PPARα expression is upregulated in diseased tissues such as melanoma, chronic lymphocytic leukemia, ovarian and prostate cancer. This may allow for cellular proliferation and metastasis. Importantly, genetic knockouts of PPARα have been shown to be protected against tumor growth in a variety of syngeneic tumors models. We hypothesized that a potent and selective PPARα antagonist could represent a novel cancer therapy. Early in our discovery research, we identified NXT629 (Bravo et al., 2014). Herein we describe the pharmacology of NXT629 and demonstrate that it is a potent and selective PPARα antagonist. We identify NXT629 as a valuable tool for use in in vivo assessment of PPARα due to its good systemic exposure following intraperitoneal injection. We explore the in vivo pharmacology of NXT629 and demonstrate that it is efficacious in pharmacodynamic models that are driven by PPARα. Finally, we probe the efficacy of NXT629 in disease models where PPARα knockouts have shown to be protected. We believe that PPARα antagonists will be beneficial in diseases such as ovarian cancer and melanoma where PPARα and fatty acid oxidation may be involved.

The design and optimization of a novel isoxazole S(1) linker for renin inhibitor is described herein. This effort culminated in the identification of compound 18, an orally bioavailable, sub-nanomolar renin inhibitor even in the presence of human plasma. When compound 18 was found to inhibit CYP3A4 in a time dependent manner, two strategies were pursued that successfully delivered equipotent compounds with minimal TDI potential.

We have been focused on identifying a structurally different next generation inhibitor to MK-5172 (our Ns3/4a protease inhibitor currently under regulatory review), which would achieve superior pangenotypic activity with acceptable safety and pharmacokinetic profile. These efforts have led to the discovery of a novel class of HCV NS3/4a protease inhibitors containing a unique spirocyclic-proline structural motif. The design strategy involved a molecular-modeling based approach, and the optimization efforts on the series to obtain pan-genotypic coverage with good exposures on oral dosing. One of the key elements in this effort was the spirocyclization of the P2 quinoline group, which rigidified and constrained the binding conformation to provide a novel core. A second focus of the team was also to improve the activity against genotype 3a and the key mutant variants of genotype 1b. The rational application of structural chemistry with molecular modeling guided the design and optimization of the structure-activity relationships have resulted in the identification of the clinical candidate MK-8831 with excellent pan-genotypic activity and safety profile.

An oral bioavailability issue encountered during the course of lead optimization in the renin program is described herein. The low F(po) of pyridone analogs was shown to be caused by a combination of poor passive permeability and gut efflux transport. Substitution of pyridone ring for a more lipophilic moiety (logD>1.7) had minimal effect on rMdr1a transport but led to increased passive permeability (P(app)>10 × 10(-6) cm/s), which contributed to overwhelm gut transporters and increase rat F(po). LogD and in vitro passive permeability determination were found to be key in guiding SAR and improve oral exposure of renin inhibitors.

The incorporation of a carboxylic acid within in a series of 3-amido-4-aryl substituted piperidines (represented by general structure 32) led to the discovery of potent, zwitterionic, renin inhibitors with improved off-target profiles (CYP3A4 time-dependent inhibition and hERG affinity) relative to analogous non-zwitterionic inhibitors of the past (i.e., 3). Strategies to address the oral absorption of these zwitterions are also discussed within.

The discovery and SAR of a series of potent renin inhibitors possessing a novel biaryl scaffold are described herein. Molecular modeling revealed that the cyclopropylamide spacer present in 1 can be replaced by a simple, substituted aromatic ring such as a toluene in 2. The resulting compounds exhibit subnanomolar renin IC50 and good oral bioavailability in rats.

The synthesis of pyrazino[1,2-a]indoles via a palladium-catalyzed double allylic alkylation of indole-2-hydroxamates is described. The reaction conditions are very mild and allow for a wide variety of substitutions on the indole core.

A new omnidirectional monopole antenna well suited to application in a wireless universal serial bus dongle for wideband operation is presented. The antenna is an L-shaped metal-plate monopole antenna consisting of a rectangular monopole element and a matching portion. The antenna is suitable to be mounted at the top region of a host dongle as a concealed antenna and can provide a very wide operating bandwidth of larger than 6.8 GHz (∼3.4–10.2 GHz). In addition, omnidirectional radiation is obtained for frequencies across the operating bandwidth. Effects of the system ground-plane length on the antenna's impedance and radiation characteristics are also analyzed. Details of the proposed antenna are described, and a prototype of the design example is constructed and studied. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 625–628, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22217

A promising planar inverted-F metal-strip antenna suitable for Bluetooth headset application is studied. The antenna has a low-profile appearance and can be embedded inside the housing of the Bluetooth headset to operate as an internal antenna. The antenna is to be mounted along the side edge of the system circuit board of the headset, almost not occupying the valuable board space. Results have indicated that, when the antenna is mounted at either end of the side edge, a large bandwidth (>250 MHz) centered at about 2442 MHz can be achieved, making the antenna easily cover the Bluetooth operation in the 2400–2484 MHz band. Performances of the studied antenna attached to the user's head are also studied. Large distortion in the antenna's radiation pattern is observed. However, the antenna's radiation efficiency is still larger than about 70% over the operating band, which is acceptable for practical applications. Details of the obtained experimental and simulation results are presented and discussed. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 19–23, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22047