84 results on '"Bennett RD"'
Search Results
2. The antioxidant drink 'effective microorganism-X (EM-X)' pre-treatment attenuates the loss of nigrostriatal dopaminergic neurons in 6-hydroxydopamine-lesion rat model of Parkinson’s disease
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Theeshan Bahorun, Okezie I. Aruoma, Higa T, Bennett Rd, Zbarsky, Ke B, Krishna P. Datla, David T. Dexter, and Yun-Fei Liang
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Male ,medicine.medical_specialty ,Time Factors ,Parkinson's disease ,Tyrosine 3-Monooxygenase ,Dopamine ,Pharmaceutical Science ,Substantia nigra ,Neuroprotection ,Antioxidants ,Beverages ,Rats, Sprague-Dawley ,Internal medicine ,medicine ,Animals ,Glycosides ,Kaempferols ,Oxidopamine ,Neurons ,Pharmacology ,Dose-Response Relationship, Drug ,Tyrosine hydroxylase ,Pars compacta ,Chemistry ,Dopaminergic ,Parkinson Disease ,medicine.disease ,Corpus Striatum ,Rats ,Substantia Nigra ,Neuroprotective Agents ,Endocrinology ,Monoamine neurotransmitter ,nervous system ,Biochemistry ,3,4-Dihydroxyphenylacetic Acid ,medicine.drug - Abstract
There is continued interest in the assessment and potential use of antioxidants as neuroprotective agents in diseases associated with increased oxidative stress, such as Parkinson's disease. The neuroprotective effect of a natural antioxidant drink, EM-X (a ferment derivative of unpolished rice, papaya and seaweeds with effective microorganisms), was investigated using the 6-hydroxydopamine (6-OHDA)-lesion rat model of Parkinson's disease. The nigrostriatal dopaminergic neurons were unilaterally lesioned with 6-OHDA (8 μg) in rats that were treated with a 10-times diluted EM-X drink (dilEM-X), standard EM-X drink (stdEM-X) or tap water for 4 days. Seven days post lesion, the integrity (no. of tyrosine hydroxylase positive cells (TH+ cells) in the substantia nigra pars compacta (SNpc)) and functionality (dopamine and its metabolites DOPAC and HVA content in the striata) of nigrostriatal dopaminergic neurons were assessed. In the vehicle-treated rats, infusion of 8 μg of 6-OHDA significantly reduced the number of TH+ cells in the SNpc as well as the levels of dopamine, DOPAC and HVA in the striata on the lesion side. The loss of TH+ cells, dopamine and HVA, but not the DOPAC levels, was significantly attenuated by stdEM-X pretreatment, but not by the dilEM-X pretreatment. There were no significant changes in the TH+ cells, or in the monoamine levels with the EM-X pretreatment per se, except for a small but significant fall in the levels of dopamine with the stdEM-X. The evidence presented supports the potential neuroprotective effects of stdEM-X drink, although its effect on dopamine levels needs further investigation.
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- 2004
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3. Shell and Jacket Corrosion of a Foamed In-Place Thermally Insulated Liquefied Petroleum Gas Tank
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Taylor, DO, primary and Bennett, RD, additional
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4. Limonoate dehydrogenase from Arthrobacter globiformis
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King Ad, Maier Vp, Bennett Rd, and Shin Hasegawa
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Biochemistry ,Chemistry ,Limonoate dehydrogenase ,Arthrobacter globiformis ,General Chemistry ,Arthrobacter ,General Agricultural and Biological Sciences ,Oxidoreductases ,Soil Microbiology - Published
- 1972
5. Integration of lipidomics with targeted, single cell, and spatial transcriptomics defines an unresolved pro-inflammatory state in colon cancer.
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Soundararajan R, Maurin MM, Rodriguez-Silva J, Upadhyay G, Alden AJ, Gowda SGB, Schell MJ, Yang M, Levine NJ, Gowda D, Sundaraswamy PM, Hui SP, Pflieger L, Wang H, Marcet J, Martinez C, Bennett RD, Chudzinski A, Karachristos A, Nywening TM, Cavallaro PM, Anderson ML, Coffey RJ, Nebozhyn MV, Loboda A, Coppola D, Pledger WJ, Halade G, and Yeatman TJ
- Abstract
Background: Over a century ago, Virchow proposed that cancer represents a chronically inflamed, poorly healing wound. Normal wound healing is represented by a transitory phase of inflammation, followed by a pro-resolution phase, with prostaglandin (PGE2/PGD2)-induced 'lipid class switching' producing inflammation-quenching lipoxins (LXA4, LXB4)., Objective: We explored if lipid dysregulation in colorectal cancers (CRCs) is driven by a failure to resolve inflammation., Design: We performed liquid chromatography and tandem mass spectrometry (LC-MS/MS) untargeted analysis of 40 human CRC and normal paired samples and targeted, quantitative analysis of 81 human CRC and normal paired samples. We integrated analysis of lipidomics, quantitative reverse transcription-PCR, large scale gene expression, and spatial transcriptomics with public scRNASEQ data to characterize pattern, expression and cellular localisation of genes that produce and modify lipid mediators., Results: Targeted, quantitative LC-MS/MS demonstrated a marked imbalance of pro-inflammatory mediators, with a dearth of resolving lipid mediators. In tumours, we observed prominent over-expression of arachidonic acid derivatives, the genes encoding their synthetic enzymes and receptors, but poor expression of genes producing pro-resolving synthetic enzymes and resultant lipoxins (LXA4, LXB4) and associated receptors. These results indicate that CRC is the product of defective lipid class switching likely related to inadequate or ineffective levels of PGE2/PGD2., Conclusion: We show that the lipidomic profile of CRC tumours exhibits a distinct pro-inflammatory bias with a deficiency of endogenous resolving mediators secondary to defective lipid class switching. These observations pave the way for 'resolution medicine', a novel therapeutic approach for inducing or providing resolvins to mitigate the chronic inflammation driving cancer growth and progression., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2024
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6. Robotic Assisted Lapendoscopic Single-Site Surgery for Ileal Deep Endometriosis. A Case Report and Review of Literature.
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Marks D, Alden AJ, Encalada-Soto D, Bennett RD, and Mikhail E
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The prevalence of deep endometriosis invading the bowel is unknown but has been estimated to affect between 3.8% and 37% of women with endometriosis. The most common locations of bowel endometriosis are the sigmoid colon and rectum. Endometriosis affecting the small bowel is exceedingly rare. Laparoendoscopic single-site port surgery (LESS) and robotic-assisted LESS (R-LESS) offer potential advantages in cosmesis and surgical recovery while safely and effectively treating disease. R-LESS is an effective and safe technique for surgical excision of deep endometriosis of the small bowel while utilizing the same access incision as a retrieval site for the surgical specimen. We present a case of a surgical excision of double nodules of deep endometriosis of the small bowel, that was managed using the R-LESS technique, and discuss the proposed advantages and technical challenges.
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- 2024
7. Knowledge and intention to use long-acting reversible contraception among university students.
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Asdell SM, Bennett RD, Cordon SA, Zhao Q, and Peipert JF
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- Humans, Female, Universities, Cross-Sectional Studies, Adult, Young Adult, Adolescent, Contraception Behavior psychology, Contraception Behavior statistics & numerical data, Surveys and Questionnaires, Students psychology, Students statistics & numerical data, Health Knowledge, Attitudes, Practice, Long-Acting Reversible Contraception statistics & numerical data, Long-Acting Reversible Contraception psychology, Intention
- Abstract
Objective: To assess the relationship between knowledge of long-acting reversible contraception (LARC) and intention to use LARC among female students., Participants: Participants consisted of a convenience sample of 292 female undergraduate and graduate students at a large midwestern university., Methods: We conducted a cross-sectional in-person survey and multivariate analysis of LARC knowledge and intention to use LARC., Results: Total response rate was 84.9%. Among contraceptive users, 13.3% were using a LARC method. On average, respondents scored 4.8/10 (SD 2.5) on a 10-item LARC knowledge assessment. Higher levels of LARC knowledge were associated with the intent to use LARC in the future in our multivariate analysis (RR 1.7, 95% CI 1.14-2.54: p = .01). Common reasons for LARC hesitancy were a need for more information, safety concerns, and risk of undesirable side effects., Conclusions: Low LARC knowledge and students' self-identified need for further LARC information represent an opportunity for campus contraceptive interventions which empower students to make informed reproductive decisions.
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- 2024
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8. Modified Graham Patch Repair of Small Bowel Anastomotic Leak.
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Alden A and Bennett RD
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- Aged, Female, Humans, Colectomy methods, Ileostomy, Intestinal Perforation surgery, Intestinal Perforation etiology, Intestine, Small surgery, Laparoscopy, Anastomosis, Surgical, Anastomotic Leak surgery, Anastomotic Leak etiology
- Abstract
The modified Graham patch repair is a well-established technique for management of perforating foregut injuries, often learned by surgeons during general surgery training. There is, however, little to no data regarding the utilization of this technique for perforation of the distal midgut or in the re-operative field. We present two cases of midgut anastomotic complications successfully managed with modified graham patch repair at our institution. The first case is a 79-year-old female who underwent an emergent right hemicolectomy at an outside institution for management of an iatrogenic perforation during endoscopic polypectomy. Over the course of two years she underwent numerous abdominal operations, due to various complications, ultimately resulting in multiple resections and end ileostomy creation. She then had her ileostomy reversed by laparoscopic single incision (SILS) technique at our institution. This was also complicated by anastomotic leak. Intraoperatively, adequate mobilization of the anastomosis for resection was deemed not safe due to dense fibrosis and adhesions in the re-operative field; therefore, she underwent a SILS modified Graham patch repair of an ileocolic anastomotic defect with diverting loop ileostomy. Post-operatively, she had no radiographic evidence of leak from the repaired anastomosis, which facilitated successful loop ileostomy reversal five months later. Our second case is a 64-year-old male referred to our institution for management of his stage IV colon cancer. He underwent an open right hemicolectomy and hepatic metastectomy, which was complicated by anastomotic leak. The small defect was repaired via a SILS modified Graham patch technique. Five months postoperatively, he had neither radiographic nor endoscopic evidence of a leak; therefore, he successfully underwent ileostomy reversal without complication. We encourage further investigation and reporting of the role of the modified graham patch repair in management of midgut anastomotic complications, particularly when resection and re-anastomosis is unsafe due to a hostile re-operative field., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2024
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9. Examining surgeon stress in robotic and laparoscopic surgery.
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Sujka J, Ahmed A, Kang R, Grimsley EA, Weche M, Janjua H, Mi Z, English D, Martinez C, Velanovich V, Bennett RD, Docimo S, Saad AR, DuCoin C, and Kuo PC
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- Humans, Hydrocortisone analysis, Amylases, Robotic Surgical Procedures methods, Surgeons, Laparoscopy
- Abstract
Robotic surgery may decrease surgeon stress compared to laparoscopic. To evaluate intraoperative surgeon stress, we measured salivary alpha-amylase and cortisol. We hypothesized robotic elicited lower increases in surgeon salivary amylase and cortisol than laparoscopic. Surgical faculty (n = 7) performing laparoscopic and robotic operations participated. Demographics: age, years in practice, time using laparoscopic vs robotic, comfort level and enthusiasm for each. Operative data included operative time, WRVU (surgical "effort"), resident year. Saliva was collected using passive drool collection system at beginning, middle and end of each case; amylase and cortisol measured using ELISA. Standard values were created using 7-minute exercise (HIIT), collecting saliva pre- and post-workout. Linear regression and Student's t test used for statistical analysis; p values < 0.05 were significant. Ninety-four cases (56 robotic, 38 laparoscopic) were collected (April-October 2022). Standardized change in amylase was 8.4 ± 4.5 (p < 0.001). Among operations, raw maximum amylase change in laparoscopic and robotic was 23.4 ± 11.5 and 22.2 ± 13.4; raw maximum cortisol change was 44.21 ± 46.57 and 53.21 ± 50.36, respectively. Values normalized to individual surgeon HIIT response, WRVU, and operative time, showing 40% decrease in amylase in robotic: 0.095 ± 0.12, vs laparoscopic: 0.164 ± 0.16 (p < 0.02). Normalized change in cortisol was: laparoscopic 0.30 ± 0.44, robotic 0.22 ± 0.4 (p = NS). On linear regression (p < 0.001), surgeons comfortable with complex laparoscopic cases had lower change in normalized amylase (p < 0.01); comfort with complex robotic was not significant. Robotic may be less physiologically stressful, eliciting less increase in salivary amylase than laparoscopic. Comfort with complex laparoscopic decreased stress in robotic, suggesting laparoscopic experience is valuable prior to robotic., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)
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- 2024
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10. Synthesis of core@shell catalysts guided by Tammann temperature.
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Xiong P, Xu Z, Wu TS, Yang T, Lei Q, Li J, Li G, Yang M, Soo YL, Bennett RD, Lau SP, Tsang SCE, Zhu Y, and Li MM
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Designing high-performance thermal catalysts with stable catalytic sites is an important challenge. Conventional wisdom holds that strong metal-support interactions can benefit the catalyst performance, but there is a knowledge gap in generalizing this effect across different metals. Here, we have successfully developed a generalizable strong metal-support interaction strategy guided by Tammann temperatures of materials, enabling functional oxide encapsulation of transition metal nanocatalysts. As an illustrative example, Co@BaAl
2 O4 core@shell is synthesized and tracked in real-time through in-situ microscopy and spectroscopy, revealing an unconventional strong metal-support interaction encapsulation mechanism. Notably, Co@BaAl2 O4 exhibits exceptional activity relative to previously reported core@shell catalysts, displaying excellent long-term stability during high-temperature chemical reactions and overcoming the durability and reusability limitations of conventional supported catalysts. This pioneering design and widely applicable approach has been validated to guide the encapsulation of various transition metal nanoparticles for environmental tolerance functionalities, offering great potential to advance energy, catalysis, and environmental fields., (© 2024. The Author(s).)- Published
- 2024
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11. Fertility sparing double discoid excision of rectosigmoid deep endometriosis under robotic-integrated ultrasound guidance.
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Hardman D, Bennett RD, and Mikhail E
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- Adult, Female, Humans, Colon, Sigmoid surgery, Rectum diagnostic imaging, Rectum surgery, Rectum pathology, Endometriosis diagnostic imaging, Endometriosis surgery, Endometriosis pathology, Robotic Surgical Procedures
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Objective: To present the use of robotic-integrated ultrasound for performing a double discoid excision of multifocal rectosigmoid endometriosis., Design: Video article., Statement of Consent: The patient included in this video gave consent for publication of the video and posting of the video online, including social media, journal website, scientific literature websites (such as PubMed, ScienceDirect, Scopus), and other applicable sites., Patient: A 26-year-old G0 woman with chronic pelvic pain, dyschezia, and dysmenorrhea refractory to medical management desired future fertility. Imaging was suggestive of deep infiltrating endometriosis involving the rectosigmoid colon., Intervention: Not applicable., Main Outcome Measures: Double discoid excision of multifocal rectosigmoid endometriosis using robotic-integrated ultrasound., Results: Not applicable., Conclusions: Performing a complete preoperative evaluation in patients with suspected endometriosis is important for determining the extent of disease and necessity of a multidisciplinary approach. Robotic-integrated ultrasound can provide additional information, including the size and depth of bowel endometriosis lesions, which can play a role in surgical decision making. Performing a double discoid excision of multifocal rectosigmoid endometriosis using robotic-integrated ultrasound is a technique that can avoid the need for a segmental bowel resection., Competing Interests: Declaration of interests D.H. reports travel support from the University of South Florida. E.M. reports funding from Abbvie, Myovant, and Dotlab outside the submitted work. R.D.B. is a member of the Takeda Pharmaceuticals advisory panel., (Copyright © 2023 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.)
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- 2024
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12. Laparoscopic vs. robotic colectomy for left-sided diverticulitis.
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Rodriguez-Silva JA, Doyle W, Alden A, Poonja S, Martinez C, Chudzinski A, Marcet J, and Bennett RD
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- Humans, Colectomy methods, Retrospective Studies, Treatment Outcome, Length of Stay, Postoperative Complications epidemiology, Postoperative Complications surgery, Robotic Surgical Procedures methods, Diverticulitis surgery, Robotics, Laparoscopy methods
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Diverticulitis is a prevalent gastrointestinal disease that often warrants surgical intervention. However, the optimal approach between traditional laparoscopy (LC) and robotic-assisted laparoscopy (RAC) for diverticulitis remains unclear. Our research compares these techniques in patients diagnosed with left-sided diverticulitis treated at a single, tertiary referral center from 2019 to 2022. Among the 134 patients, 86 underwent laparoscopic and 48 robotic-assisted surgeries. The surgeries included in this analysis are left colectomy, sigmoid colectomy, low anterior resection, and Hartmann's procedure. Primary outcomes were major morbidity and 30-day mortality. Secondary outcomes were operative time, conversion to open, length of stay, unplanned return to the operating room, 30-day readmission rate, and overall morbidity. While demographics and comorbidities were similar for both groups, the robotic-assisted group displayed a statistically significant longer operative time (198.0 ± 84.4 LC vs. 264.8 ± 78.5 min RAC, p < 0.001). When investigated further, there was a significant difference in operative time for uncomplicated diverticulitis cases favoring the LC approach (169.17 ± 58.1 LC vs. 244.82 ± 58.79 min RAC, p < 0.001). This significant difference, however, was not present in complicated diverticulitis cases. Other factors, such as overall and major morbidity, rate of conversion to open approach, ostomy creation, estimated blood loss, time to return of bowel function, length of stay, and 30-day readmission rate, did not significantly differ between the groups. There was no 30-day mortality in either group. Favorable patient outcomes, lack of significant difference in operative time compared with traditional laparoscopy, and absence of differences in morbidities or efficacy, raises an interesting question in the world of minimally invasive surgery: is the robotic-assisted approach emerging as the advantageous approach for complicated diverticulitis cases? We encourage additional, multi-center analysis of specifically complicated diverticulitis managed with both surgical approaches to investigate if these findings are replicated outside of our institution., (© 2023. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)
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- 2023
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13. Deep Endometriosis of the Terminal Ileum Presenting With Cyclic Recurrent Small Bowel Obstruction.
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Ha K, Marks D, Bennett RD, and Mikhail E
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Here, we discuss a case of a 42-year-old premenopausal female who presented with chronic pelvic pain and recurrent small bowel obstruction during menstruation. The patient reported a nine-year history of pelvic pain and a four-year history of episodic small bowel obstruction requiring multiple prior inpatient admissions. During these admissions, the obstruction was managed conservatively with bowel rest and nasogastric tube placement; however, symptoms would recur with subsequent menstrual cycles. Computed tomography showed diffusely dilated loops of small bowel with a transition point in the central anterior pelvis, and magnetic resonance enterography revealed a mass-like area involving small bowel loops in the mid pelvis. The patient underwent laparoscopic surgical intervention including bowel resection with re-anastomosis, hysterectomy, bilateral salpingectomy, and left oophorectomy. Intraoperative findings included severe distention of the proximal bowel with a discrete deep endometriosis lesion of the terminal ileum which was confirmed on final pathologic examination. This case emphasizes the importance of considering endometriosis as the etiology of recurrent catamenial small bowel obstruction, particularly in premenopausal women., Competing Interests: The authors have declared financial relationships, which are detailed in the next section., (Copyright © 2023, Ha et al.)
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- 2023
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14. Robotic Transanal Minimally Invasive Surgery (rTAMIS): Large Tubulovillous Adenoma.
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Rodriguez-Silva JA and Bennett RD
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- Humans, Minimally Invasive Surgical Procedures, Anal Canal, Robotic Surgical Procedures, Rectal Neoplasms surgery, Robotics, Transanal Endoscopic Surgery, Gastrointestinal Neoplasms, Adenoma surgery
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Many transanal platforms have recently evolved to manage rectal pathologies. Transanal endoscopic microsurgery (TEM) and transanal laparoscopic minimally invasive surgery (TAMIS) have been developed to address the limitations of conventional transanal surgery. More recently, the addition of the robotic platform to the surgeon's armamentarium has made it possible to combine the dexterity of the robotic surgical system with the standard TAMIS single-port platform to treat complex rectal lesions. In this article, we present the case of a patient who underwent rTAMIS for the management of a large endoscopically unresectable rectal mass.
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- 2023
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15. Rare Presentation of Umbilical Condyloma.
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Ward CC, Moro A, and Bennett RD
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- Humans, Umbilicus surgery, Syphilis complications, Syphilis, Cutaneous complications, HIV Infections complications
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Syphilis is associated with 3 stages of infection-primary, secondary, and tertiary-each with their own associated clinical findings. Secondary syphilis manifests with condyloma lata and other cutaneous findings, and typically occurs several months after the initial infection. Condyloma lata are primarily found in the genital area, but may also be found in other locations such as the umbilicus, axilla, and neck. This brief report describes an umbilical condyloma lata discovered in a patient with secondary syphilis and HIV co-infection and discusses surgical excision and fulguration as an option for definitive management.
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- 2023
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16. Pneumoperitoneum, Pneumoretroperitoneum, and Pneumoscrotum Following Transanal Excision of Rectal Polyp.
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Sunderland MS, Dakwar A, Rishi A, and Bennett RD
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- Humans, Rectum surgery, Retropneumoperitoneum diagnostic imaging, Retropneumoperitoneum etiology, Retropneumoperitoneum surgery, Pneumoperitoneum diagnostic imaging, Pneumoperitoneum etiology, Pneumoperitoneum surgery, Rectal Neoplasms surgery, Digestive System Surgical Procedures, Transanal Endoscopic Surgery
- Abstract
Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2023
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17. Ultrasound-integrated robotic identification of an isolated deep infiltrating endometriosis nodule of the sigmoid colon.
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Mikhail E, Amis J, and Bennett RD
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- Female, Humans, Colon, Sigmoid, Rectum, Endometriosis diagnostic imaging, Endometriosis surgery, Robotic Surgical Procedures, Rectal Diseases surgery, Laparoscopy
- Published
- 2023
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18. Mushroom Cap a Sign of Rectosigmoid Deep Infiltrating Endometriosis on MRI Corresponding to Surgical Specimen.
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Mikhail E and Bennett RD
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- Colon, Female, Humans, Magnetic Resonance Imaging, Rectum diagnostic imaging, Rectum surgery, Ultrasonography, Endometriosis diagnostic imaging, Endometriosis surgery, Rectal Diseases diagnostic imaging, Rectal Diseases surgery
- Published
- 2022
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19. Loop Ileostomy for Management of Toxic Clostridium difficile Enteritis and Bowel Obstruction After Restorative Proctocolectomy.
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Reddy NC and Bennett RD
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- Humans, Ileostomy, Postoperative Complications surgery, Clostridioides difficile, Colitis, Ulcerative surgery, Enteritis etiology, Enteritis surgery, Intestinal Obstruction etiology, Intestinal Obstruction surgery, Proctocolectomy, Restorative adverse effects
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- 2022
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20. Tunable transition metal complexes as hole transport materials for stable perovskite solar cells.
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Lin L, Lian C, Jones TW, Bennett RD, Mihaylov B, Yang TC, Wang JT, Chi B, Duffy NW, Li J, Wang X, Snaith HJ, and Wilson GJ
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Transition metal complexes offer cost-effective alternatives as hole-transport materials (HTMs) in perovskite solar cells. However, the devices suffer from low performance. We boost the power conversion efficiency of devices with transition metal complex HTMs from 2% to above 10% through energy level tuning. We further demonstrate the excellent photostability of the device based on the additive-free HTM.
- Published
- 2021
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21. Single-Cell Transcriptional Profiling of Cells Derived From Regenerating Alveolar Ducts.
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Ysasi AB, Bennett RD, Wagner W, Valenzuela CD, Servais AB, Tsuda A, Pyne S, Li S, Grimsby J, Pokharel P, Livak KJ, Ackermann M, Blainey PC, and Mentzer SJ
- Abstract
Lung regeneration occurs in a variety of adult mammals after surgical removal of one lung (pneumonectomy). Previous studies of murine post-pneumonectomy lung growth have identified regenerative "hotspots" in subpleural alveolar ducts; however, the cell-types participating in this process remain unclear. To identify the single cells participating in post-pneumonectomy lung growth, we used laser microdissection, enzymatic digestion and microfluidic isolation. Single-cell transcriptional analysis of the murine alveolar duct cells was performed using the C1 integrated fluidic circuit (Fluidigm) and a custom PCR panel designed for lung growth and repair genes. The multi-dimensional data set was analyzed using visualization software based on the tSNE algorithm. The analysis identified 6 cell clusters; 1 cell cluster was present only after pneumonectomy. This post-pneumonectomy cluster was significantly less transcriptionally active than 3 other clusters and may represent a transitional cell population. A provisional cluster identity for 4 of the 6 cell clusters was obtained by embedding bulk transcriptional data into the tSNE analysis. The transcriptional pattern of the 6 clusters was further analyzed for genes associated with lung repair, matrix production, and angiogenesis. The data demonstrated that multiple cell-types (clusters) transcribed genes linked to these basic functions. We conclude that the coordinated gene expression across multiple cell clusters is likely a response to a shared regenerative microenvironment within the subpleural alveolar ducts., (Copyright © 2020 Ysasi, Bennett, Wagner, Valenzuela, Servais, Tsuda, Pyne, Li, Grimsby, Pokharel, Livak, Ackermann, Blainey and Mentzer.)
- Published
- 2020
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22. Physical characteristics of capacitive carbons derived from the electrolytic reduction of alkali metal carbonate molten salts.
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Hughes MA, Bennett RD, Allen JA, and Donne SW
- Abstract
Carbons have been synthesized through the reduction of molten carbonate systems under varied conditions. The mechanism and kinetics of carbon electrodeposition has been investigated. Carbon morphologies include amorphous, graphite-like, and spherical aggregate phases. Increased graphitic character is observed in carbons electrodeposited at more cathodic potentials, particularly at higher temperatures. Bonding has been investigated and oxygen functionalised sp
2 and sp3 structures have been identified. The level of functionalization decreases in carbons with reduced amorphous and increased graphitic character. Thermal decomposition of electrodepositied carbons has been investigated and zero order kinetics have been identified. A relationship has been identified between elevated oxygen functionalization and increased pseudo-capacitance, with carbons deposited at 0.15 A cm-2 showing capacitances of 400 F g-1 in 0.5 M H2 SO4 at sweep rates of 10 mV s-1 ., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)- Published
- 2019
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23. Toward Automation of the Supine Pressor Test for Preeclampsia.
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Qureshi HJ, Ma JL, Anderson JL, Bosinski BM, Acharya A, Bennett RD, Haas DM, Cox AD, Wodicka GR, Reuter DG, and Goergen CJ
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Preeclampsia leads to increased risk of morbidity and mortality for both mother and fetus. Most previous studies have largely neglected mechanical compression of the left renal vein by the gravid uterus as a potential mechanism. In this study, we first used a murine model to investigate the pathophysiology of left renal vein constriction. The results indicate that prolonged renal vein stenosis after 14 days can cause renal necrosis and an increase in blood pressure (BP) of roughly 30 mmHg. The second part of this study aimed to automate a diagnostic tool, known as the supine pressor test (SPT), to enable pregnant women to assess their preeclampsia development risk. A positive SPT has been previously defined as an increase of at least 20 mmHg in diastolic BP when switching between left lateral recumbent and supine positions. The results from this study established a baseline BP increase between the two body positions in nonpregnant women and demonstrated the feasibility of an autonomous SPT in pregnant women. Our results demonstrate that there is a baseline increase in BP of roughly 10-14 mmHg and that pregnant women can autonomously perform the SPT. Overall, this work in both rodents and humans suggests that (1) stenosis of the left renal vein in mice leads to elevation in BP and acute renal failure, (2) nonpregnant women experience a baseline increase in BP when they shift from left lateral recumbent to supine position, and (3) the SPT can be automated and used autonomously.
- Published
- 2019
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24. Evidence of commitment to research partnerships? Results of two web reviews.
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de Moissac D, Bowen S, Botting I, Graham ID, MacLeod M, Harlos K, Songok CM, and Bohémier M
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- Canada, Cooperative Behavior, Humans, Internet, Leadership, Translational Research, Biomedical, Administrative Personnel organization & administration, Health Services Research organization & administration, Interinstitutional Relations, Research Personnel organization & administration, Universities organization & administration
- Abstract
Background: Partnerships between academic researchers and health system leadership are often promoted by health research funding agencies as an important strategy in helping ensure that funded research is relevant and the results used. While potential benefits of such partnerships have been identified, there is limited guidance in the scientific literature for either healthcare organisations or researchers on how to select, build and manage effective research partnerships. Our main research objective was to explore the health system perspective on partnerships with researchers with a focus on issues related to the design and organisation of the health system and services. Two structured web reviews were conducted as one component of this larger study., Methods: Two separate structured web reviews were conducted using structured data extraction tools. The first review focused on sites of health research bodies and those providing information on health system management and knowledge translation (n = 38) to identify what guidance to support partnerships might be available on websites commonly accessed by health leaders and researchers. The second reviewed sites from all health 'regions' in Canada (n = 64) to determine what criteria and standards were currently used in guiding decisions to engage in research partnerships; phone follow-up ensured all relevant information was collected., Results: Absence of guidance on partnerships between research institutions and health system leaders was found. In the first review, absence of guidance on research partnerships and knowledge coproduction was striking and in contrast with coverage of other forms of collaboration such as patient/community engagement. In the second review, little evidence of criteria and standards regarding research partnerships was found. Difficulties in finding appropriate contact information for those responsible for research and obtaining a response were commonly experienced., Conclusion: Guidance related to health system partnerships with academic researchers is lacking on websites that should promote and support such collaborations. Health region websites provide little evidence of partnership criteria and often do not make contact information to research leaders within health systems readily available; this may hinder partnership development between health systems and academia.
- Published
- 2019
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25. Extracellular Assembly of the Elastin Cable Line Element in the Developing Lung.
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Valenzuela CD, Wagner WL, Bennett RD, Ysasi AB, Belle JM, Molter K, Straub BK, Wang D, Chen Z, Ackermann M, Tsuda A, and Mentzer SJ
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- Animals, Animals, Newborn, Female, Lung metabolism, Lung ultrastructure, Pregnancy, Rats, Wistar, Lung embryology, Tropoelastin metabolism
- Abstract
In the normal lung, a dominant structural element is an elastic "line element" that originates in the central bronchi and inserts into the distal airspaces. Despite its structural importance, the process that leads to development of the cable line element is unknown. To investigate the morphologic events contributing to its development, we used optical clearing methods to examine the postnatal rat lung. An unexpected finding was numerous spheres, with a median diameter of 1-2 µm, within the primary septa of the rat lung. The spheres demonstrated green autofluorescence, selective fluorescent eosin staining, reactivity with carboxyfluorescein succinimidyl ester, and specific labeling with anti-tropoelastin monoclonal antibody-findings consistent with tropoelastin. The sphere number peaked on rat postnatal day 4 (P4) and were rare by P14. The disappearance of the spheres was coincident with the development of the cable line element in the rat lung. Transmission electron microscopy demonstrated no consistent association between parenchymal cells and sphere alignment. In contrast, the alignment of tropoelastin spheres appeared to be the direct result of interactions of scaffold proteins including collagen fibers and fibrillin microfibrils. We conclude that the spatial organization of the cable line element appears to be independent of tropoelastin deposition, but dependent on crosslinking to scaffold proteins within the primary septa. Anat Rec, 300:1670-1679, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)
- Published
- 2017
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26. A case of fatal internal jugular vein perforation during nasogastric tube insertion.
- Author
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Smith KA, Fleming JP, Bennett RD, and Taitano AA
- Abstract
Nasogastric tube (NGT) insertion is a routine procedure in the management of surgical patients. We report the second case of internal jugular vein perforation during NGT insertion. A 79-year-old man presented with diffuse abdominal pain secondary to a perforated viscus. Abdominal CT revealed pneumoperitoneum, necessitating emergent exploratory laparotomy. On post-operative Day 7, the patient developed mild abdominal distension and subjective nausea for which NGT placement was ordered for decompression. Tube placement was confirmed by insufflation of air without aspiration of gastric contents. Output from the NGT upon placement revealed frank blood. The patient then developed respiratory distress requiring intubation, followed by a fatal arrhythmia. Post-mortem exam revealed the trajectory of the NGT through the pharyngeal wall into the right internal jugular vein. This case illustrates the importance of systematic evaluation of all procedures, as the outcome resulted from failure to recognize the initial error in tube placement.
- Published
- 2017
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27. Evidence for pleural epithelial-mesenchymal transition in murine compensatory lung growth.
- Author
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Ysasi AB, Wagner WL, Valenzuela CD, Kienzle A, Servais AB, Bennett RD, Tsuda A, Ackermann M, and Mentzer SJ
- Subjects
- Animals, Lung surgery, Male, Mice, Mice, Inbred C57BL, Organogenesis, Phenotype, Pleura surgery, Epithelial-Mesenchymal Transition, Lung growth & development, Lung pathology, Pleura growth & development, Pleura pathology, Pneumonectomy
- Abstract
In many mammals, including rodents and humans, removal of one lung results in the compensatory growth of the remaining lung; however, the mechanism of compensatory lung growth is unknown. Here, we investigated the changes in morphology and phenotype of pleural cells after pneumonectomy. Between days 1 and 3 after pneumonectomy, cells expressing α-smooth muscle actin (SMA), a cytoplasmic marker of myofibroblasts, were significantly increased in the pleura compared to surgical controls (p < .01). Scanning electron microscopy of the pleural surface 3 days post-pneumonectomy demonstrated regions of the pleura with morphologic features consistent with epithelial-mesenchymal transition (EMT); namely, cells with disrupted intercellular junctions and an acquired mesenchymal (rounded and fusiform) morphotype. To detect the migration of the transitional pleural cells into the lung, a biotin tracer was used to label the pleural mesothelial cells at the time of surgery. By post-operative day 3, image cytometry of post-pneumonectomy subpleural alveoli demonstrated a 40-fold increase in biotin+ cells relative to pneumonectomy-plus-plombage controls (p < .01). Suggesting a similar origin in space and time, the distribution of cells expressing biotin, SMA, or vimentin demonstrated a strong spatial autocorrelation in the subpleural lung (p < .001). We conclude that post-pneumonectomy compensatory lung growth involves EMT with the migration of transitional mesothelial cells into subpleural alveoli.
- Published
- 2017
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28. Role of Diet and Nutritional Supplements in Parkinson's Disease Progression.
- Author
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Mischley LK, Lau RC, and Bennett RD
- Subjects
- Disease Progression, Female, Humans, Male, Middle Aged, Diet methods, Dietary Supplements statistics & numerical data, Parkinson Disease therapy
- Abstract
Objectives: The goal of this study is to describe modifiable lifestyle variables associated with reduced rate of Parkinson's disease (PD) progression., Methods: The patient-reported outcomes in PD (PRO-PD) were used as the primary outcome measure, and a food frequency questionnaire (FFQ) was used to assess dietary intake. In this cross-sectional analysis, regression analysis was performed on baseline data to identify the nutritional and pharmacological interventions associated with the rate of PD progression. All analyses were adjusted for age, gender, and years since diagnosis., Results: 1053 individuals with self-reported idiopathic PD were available for analysis. Foods associated with the reduced rate of PD progression included fresh vegetables, fresh fruit, nuts and seeds, nonfried fish, olive oil, wine, coconut oil, fresh herbs, and spices ( P < 0.05). Foods associated with more rapid PD progression include canned fruits and vegetables, diet and nondiet soda, fried foods, beef, ice cream, yogurt, and cheese ( P < 0.05). Nutritional supplements coenzyme Q10 and fish oil were associated with reduced PD progression ( P = 0.026 and P = 0.019, resp.), and iron supplementation was associated with faster progression ( P = 0.022)., Discussion: These are the first data to provide evidence that targeted nutrition is associated with the rate of PD progression.
- Published
- 2017
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29. Deformation-induced transitional myofibroblasts contribute to compensatory lung growth.
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Bennett RD, Ysasi AB, Wagner WL, Valenzuela CD, Tsuda A, Pyne S, Li S, Grimsby J, Pokharel P, Livak KJ, Ackermann M, Blainey P, and Mentzer SJ
- Subjects
- Actins metabolism, Animals, Cell Separation, Gene Expression Regulation, Developmental, Image Cytometry, Lung metabolism, Lung surgery, Male, Mice, Inbred C57BL, Pneumonectomy, Polymerase Chain Reaction, Single-Cell Analysis, Transcription, Genetic, Lung growth & development, Myofibroblasts metabolism, Myofibroblasts pathology, Stress, Mechanical
- Abstract
In many mammals, including humans, removal of one lung (pneumonectomy) results in the compensatory growth of the remaining lung. Compensatory growth involves not only an increase in lung size, but also an increase in the number of alveoli in the peripheral lung; however, the process of compensatory neoalveolarization remains poorly understood. Here, we show that the expression of α-smooth muscle actin (SMA)-a cytoplasmic protein characteristic of myofibroblasts-is induced in the pleura following pneumonectomy. SMA induction appears to be dependent on pleural deformation (stretch) as induction is prevented by plombage or phrenic nerve transection (P < 0.001). Within 3 days of pneumonectomy, the frequency of SMA
+ cells in subpleural alveolar ducts was significantly increased (P < 0.01). To determine the functional activity of these SMA+ cells, we isolated regenerating alveolar ducts by laser microdissection and analyzed individual cells using microfluidic single-cell quantitative PCR. Single cells expressing the SMA (Acta2) gene demonstrated significantly greater transcriptional activity than endothelial cells or other discrete cell populations in the alveolar duct (P < 0.05). The transcriptional activity of the Acta2+ cells, including expression of TGF signaling as well as repair-related genes, suggests that these myofibroblast-like cells contribute to compensatory lung growth., (Copyright © 2017 the American Physiological Society.)- Published
- 2017
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30. Endotherapies for Barrett esophagus.
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Bennett RD and Velanovich V
- Subjects
- Adenocarcinoma diagnosis, Early Detection of Cancer, Esophageal Neoplasms diagnosis, Humans, Population Surveillance, Precancerous Conditions pathology, Risk Factors, Treatment Outcome, Barrett Esophagus diagnosis, Barrett Esophagus surgery, Catheter Ablation methods, Esophagoscopy methods, Precancerous Conditions surgery
- Abstract
Barrett esophagus (BE) is becoming an increasingly common complication. It places patients at higher risk for esophageal adenocaricnoma. Surveillance and acid suppression has been the mainstay of treatment. Recent advances in endoscopic therapies have allowed irradication of BE and reduction in cancer risk. This article reviews the available endotherapies and their efficacy.
- Published
- 2016
31. Elastin Cables Define the Axial Connective Tissue System in the Murine Lung.
- Author
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Wagner W, Bennett RD, Ackermann M, Ysasi AB, Belle J, Valenzuela CD, Pabst A, Tsuda A, Konerding MA, and Mentzer SJ
- Subjects
- Animals, Connective Tissue metabolism, Connective Tissue ultrastructure, Lung cytology, Lung metabolism, Lung ultrastructure, Male, Mice, Mice, Inbred C57BL, Microscopy, Electron, Scanning, Connective Tissue anatomy & histology, Elastin metabolism, Lung anatomy & histology
- Abstract
The axial connective tissue system is a fiber continuum of the lung that maintains alveolar surface area during changes in lung volume. Although the molecular anatomy of the axial system remains undefined, the fiber continuum of the lung is central to contemporary models of lung micromechanics and alveolar regeneration. To provide a detailed molecular structure of the axial connective tissue system, we examined the extracellular matrix of murine lungs. The lungs were decellularized using a 24 hr detergent treatment protocol. Systematic evaluation of the decellularized lungs demonstrated no residual cellular debris; morphometry demonstrated a mean 39 ± 7% reduction in lung dimensions. Scanning electron microscopy (SEM) demonstrated an intact structural hierarchy within the decellularized lung. Light, fluorescence, and SEM of precision-cut lung slices demonstrated that alveolar duct structure was defined by a cable line element encased in basement membrane. The cable line element arose in the distal airways, passed through septal tips and inserted into neighboring blood vessels and visceral pleura. The ropelike appearance, collagenase resistance and anti-elastin immunostaining indicated that the cable was an elastin macromolecule. Our results indicate that the helical line element of the axial connective tissue system is composed of an elastin cable that not only defines the structure of the alveolar duct, but also integrates the axial connective tissue system into visceral pleura and peripheral blood vessels., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2015
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32. Robotic-Assisted Esophageal Surgery.
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Straughan DM, Azoury SC, Bennett RD, Pimiento JM, Fontaine JP, and Toloza EM
- Subjects
- Esophageal Neoplasms surgery, Humans, Esophageal Diseases surgery, Esophagectomy methods, Fundoplication methods, Robotic Surgical Procedures methods
- Abstract
Background: The adoption of minimally invasive approaches to the management of esophageal disease has been slow, except for the laparoscopic management of gastroesophageal reflux disease. However, the advent of new surgical technologies - in particular, robotic-assisted surgical systems - has revolutionized esophageal surgery., Methods: The literature was systematically reviewed using the keywords "robotic," "esophageal surgery," "esophagectomy," "fundoplication," and "esophageal myotomy." The reference lists from these articles were then also analyzed., Results: Forty-nine studies were included in our comprehensive review of robotic-assisted esophageal surgery, and they consisted of literature reviews, case reports, retrospective and prospective case series, and randomized controlled trials., Conclusions: Robotic-assisted esophageal surgery is a safe and effective way of treating esophageal disorders, including gastroesophageal reflux disease, achalasia, leiomyomas, and cancer. The use of robotic surgical systems has many benefits for managing disorders of the esophagus, but more studies, including randomized controlled trials, are necessary.
- Published
- 2015
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33. Remodeling of alveolar septa after murine pneumonectomy.
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Ysasi AB, Wagner WL, Bennett RD, Ackermann M, Valenzuela CD, Belle J, Tsuda A, Konerding MA, and Mentzer SJ
- Subjects
- Animals, Male, Mice, Mice, Inbred C57BL, Microscopy, Electron, Scanning, Surface Tension, Synchrotrons, Tomography, X-Ray Computed, Neovascularization, Physiologic, Pneumonectomy, Pulmonary Alveoli blood supply, Pulmonary Alveoli growth & development
- Abstract
In most mammals, removing one lung (pneumonectomy) results in the compensatory growth of the remaining lung. In mice, stereological observations have demonstrated an increase in the number of mature alveoli; however, anatomic evidence of the early phases of alveolar growth has remained elusive. To identify changes in the lung microstructure associated with neoalveolarization, we used tissue histology, electron microscopy, and synchrotron imaging to examine the configuration of the alveolar duct after murine pneumonectomy. Systematic histological examination of the cardiac lobe demonstrated no change in the relative frequency of dihedral angle components (Ends, Bends, and Junctions) (P > 0.05), but a significant decrease in the length of a subset of septal ends ("E"). Septal retraction, observed in 20-30% of the alveolar ducts, was maximal on day 3 after pneumonectomy (P < 0.01) and returned to baseline levels within 3 wk. Consistent with septal retraction, the postpneumonectomy alveolar duct diameter ratio (Dout:Din) was significantly lower 3 days after pneumonectomy compared to all controls except for the detergent-treated lung (P < 0.001). To identify clumped capillaries predicted by septal retraction, vascular casting, analyzed by both scanning electron microscopy and synchrotron imaging, demonstrated matted capillaries that were most prominent 3 days after pneumonectomy. Numerical simulations suggested that septal retraction could reflect increased surface tension within the alveolar duct, resulting in a new equilibrium at a higher total energy and lower surface area. The spatial and temporal association of these microstructural changes with postpneumonectomy lung growth suggests that these changes represent an early phase of alveolar duct remodeling., (Copyright © 2015 the American Physiological Society.)
- Published
- 2015
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34. Laser microdissection of the alveolar duct enables single-cell genomic analysis.
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Bennett RD, Ysasi AB, Belle JM, Wagner WL, Konerding MA, Blainey PC, Pyne S, and Mentzer SJ
- Abstract
Complex tissues such as the lung are composed of structural hierarchies such as alveoli, alveolar ducts, and lobules. Some structural units, such as the alveolar duct, appear to participate in tissue repair as well as the development of bronchioalveolar carcinoma. Here, we demonstrate an approach to conduct laser microdissection of the lung alveolar duct for single-cell PCR analysis. Our approach involved three steps. (1) The initial preparation used mechanical sectioning of the lung tissue with sufficient thickness to encompass the structure of interest. In the case of the alveolar duct, the precision-cut lung slices were 200 μm thick; the slices were processed using near-physiologic conditions to preserve the state of viable cells. (2) The lung slices were examined by transmission light microscopy to target the alveolar duct. The air-filled lung was sufficiently accessible by light microscopy that counterstains or fluorescent labels were unnecessary to identify the alveolar duct. (3) The enzymatic and microfluidic isolation of single cells allowed for the harvest of as few as several thousand cells for PCR analysis. Microfluidics based arrays were used to measure the expression of selected marker genes in individual cells to characterize different cell populations. Preliminary work suggests the unique value of this approach to understand the intra- and intercellular interactions within the regenerating alveolar duct.
- Published
- 2014
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35. Stretch-induced intussuceptive and sprouting angiogenesis in the chick chorioallantoic membrane.
- Author
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Belle J, Ysasi A, Bennett RD, Filipovic N, Nejad MI, Trumper DL, Ackermann M, Wagner W, Tsuda A, Konerding MA, and Mentzer SJ
- Subjects
- Animals, Capillaries ultrastructure, Chick Embryo, Corrosion Casting, Finite Element Analysis, Microcirculation, Microscopy, Electrochemical, Scanning, Microscopy, Fluorescence, Microscopy, Video, Models, Cardiovascular, Stress, Mechanical, Time Factors, Capillaries physiology, Chorioallantoic Membrane blood supply, Mechanotransduction, Cellular, Neovascularization, Physiologic
- Abstract
Vascular systems grow and remodel in response to not only metabolic needs, but also mechanical influences as well. Here, we investigated the influence of tissue-level mechanical forces on the patterning and structure of the chick chorioallantoic membrane (CAM) microcirculation. A dipole stretch field was applied to the CAM using custom computer-controlled servomotors. The topography of the stretch field was mapped using finite element models. After 3days of stretch, Sholl analysis of the CAM demonstrated a 7-fold increase in conducting vessel intersections within the stretch field (p<0.01). The morphometric analysis of intravital microscopy and scanning electron microscopy (SEM) images demonstrated that the increase vessel density was a result of an increase in interbranch distance (p<0.01) and a decrease in bifurcation angles (p<0.01); there was no significant increase in conducting vessel number (p>0.05). In contrast, corrosion casting and SEM of the stretch field capillary meshwork demonstrated intense sprouting and intussusceptive angiogenesis. Both planar surface area (p<0.05) and pillar density (p<0.01) were significantly increased relative to control regions of the CAM. We conclude that a uniaxial stretch field stimulates the axial growth and realignment of conducting vessels as well as intussusceptive and sprouting angiogenesis within the gas exchange capillaries of the ex ovo CAM., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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36. Potentially preventable use of emergency services: the role of low health literacy.
- Author
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Schumacher JR, Hall AG, Davis TC, Arnold CL, Bennett RD, Wolf MS, and Carden DL
- Subjects
- Academic Medical Centers, Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Office Visits statistics & numerical data, United States, Emergency Service, Hospital statistics & numerical data, Health Knowledge, Attitudes, Practice, Health Literacy statistics & numerical data, Health Services Accessibility statistics & numerical data, Primary Health Care statistics & numerical data
- Abstract
Background: Limited health literacy is a barrier for understanding health information and has been identified as a risk factor for overuse of the emergency department (ED). The association of health literacy with access to primary care services in patients presenting to the ED has not been fully explored., Objective: To examine the relationship between health literacy, access to primary care, and reasons for ED use among adults presenting for emergency care., Methods: Structured interviews that included health literacy assessment were performed involving 492 ED patients at one Southern academic medical center. Unadjusted and multivariable logistic regression models assessed the relationship between health literacy and (1) access to a personal physician; (2) doctor office visits; (3) ED visits; (4) hospitalizations; and (5) potentially preventable hospital admissions., Results: After adjusting for sociodemographic and health status, those with limited health literacy reported fewer doctor office visits [odds ratio (OR)=0.6; 95% confidence interval (CI), 0.4-1.0], greater ED use, (OR=1.6; 95% CI, 1.0-2.4), and had more potentially preventable hospital admissions (OR=1.7; 95% CI, 1.0-2.7) than those with adequate health literacy. After further controlling for insurance and employment status, fewer doctor office visits remained significantly associated with patient health literacy (OR=0.5; 95% CI, 0.3-0.9). Patients with limited health literacy reported a preference for emergency care, as the services were perceived as better., Conclusions: Among ED patients, limited health literacy was independently associated with fewer doctor office visits and a preference for emergency care. Policies to reduce ED use should consider steps to limit barriers and improve attitudes toward primary care services.
- Published
- 2013
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37. Immunolocalization of the tumor-sensitive calmodulin-like protein CALML3 in normal human skin and hyperproliferative skin disorders.
- Author
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Bennett RD, Pittelkow MR, and Strehler EE
- Subjects
- Carcinoma, Basal Cell metabolism, Carcinoma, Squamous Cell metabolism, Cell Differentiation, Humans, Immunohistochemistry, Keratinocytes metabolism, Psoriasis metabolism, Warts metabolism, Calmodulin metabolism, Ki-67 Antigen metabolism, Skin metabolism, Skin Neoplasms metabolism
- Abstract
Background and Objective: Calmodulin-like protein CALML3 is an epithelial-specific protein regulated during keratinocyte differentiation in vitro. CALML3 expression is downregulated in breast cancers and transformed cell lines making it an attractive marker for tumor formation. The objective of this study was to survey CALML3 localization in normal epidermis and in hyperproliferative skin diseases including actinic keratosis, squamous and basal cell carcinoma as well as verruca and psoriasis and to compare CALML3 immunoreactivity with the proliferation marker Ki-67., Methods: Paraffin-embedded tissue sections from normal human skin and hyperproliferative skin disorders were examined by immunohistochemistry and analyzed for localization and expression of CALML3 and Ki-67., Results: CALML3 was strongly expressed in differentiating layers of normal skin, staining the periphery in suprabasal cells and exhibiting nuclear localization in the stratum granulosum. CALML3 nuclear localization was inversely correlated to Ki-67 staining in each disease, indicating that CALML3 nuclear presence is related to terminal cell differentiation and postmitotic state., Conclusions: Increased CALML3 expression in suprabasal layers is characteristic for differentiating keratinocytes in normal epidermis, and nuclear expression of CALML3 inversely correlates with expression of the proliferation marker Ki-67. This suggests that CALML3 is a useful marker for normal and benign hyperplastic epidermal development, whereas the loss of nuclear CALML3 indicates progression to a proliferative and potentially malignant phenotype.
- Published
- 2013
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38. Human Calmodulin-Like Protein CALML3: A Novel Marker for Normal Oral Squamous Mucosa That Is Downregulated in Malignant Transformation.
- Author
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Brooks MD, Bennett RD, Weaver AL, Sebo TJ, Eckert SE, Strehler EE, and Carr AB
- Abstract
Oral cancer is often diagnosed only at advanced stages due to a lack of reliable disease markers. The purpose of this study was to determine if the epithelial-specific human calmodulin-like protein (CALML3) could be used as marker for the various phases of oral tumor progression. Immunohistochemical analysis using an affinity-purified CALML3 antibody was performed on biopsy-confirmed oral tissue samples representing these phases. A total of 90 tissue specimens were derived from 52 patients. Each specimen was analyzed in the superficial and basal mucosal cell layers for overall staining and staining of cellular subcompartments. CALML3 was strongly expressed in benign oral mucosal cells with downregulation of expression as squamous cells progress to invasive carcinoma. Based on the Cochran-Armitage test for trend, expression in the nucleus and at the cytoplasmic membrane significantly decreased with increasing disease severity. Chi-square test showed that benign tissue specimens had significantly more expression compared to dysplasia/CIS and invasive specimens. Dysplasia/CIS tissue had significantly more expression than invasive tissue. We conclude that CALML3 is expressed in benign oral mucosal cells with a statistically significant trend in downregulation as tumorigenesis occurs. CALML3 may thus be a sensitive new marker for oral cancer screening.
- Published
- 2013
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39. Assignment of metal-ligand modes in Pt(II) diimine complexes relevant to solar energy conversion.
- Author
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Parker SF, Refson K, Bennett RD, Best J, Mel'nikov MY, and Weinstein JA
- Abstract
This work describes a comprehensive assignment of the vibrational spectra of the platinum(II) diimine bisthiolate and chloride complexes as a prototype structure for a diversity of Pt(II) diimine chromophores. The dynamics and energy dissipation pathways in excited states of light harvesting molecules relies largely on the coupling between the high frequency and the low frequency modes. As such, the assignment of the vibrational spectrum of the chromophore is of utmost importance, especially in the low-frequency region, below 500 cm(-1), where the key metal-ligand framework modes occur. This region is experimentally difficult to access with infrared spectroscopy and hence frequently remains elusive. However, this region is easily accessible with Raman and inelastic neutron scattering (INS) spectroscopies. Accordingly, a combination of inelastic neutron scattering and Raman spectroscopy with the aid of computational results from periodic-DFT and the mode visualizations, as well as isotopic substitution, allowed for an identification of the modes that contain significant contributions from Pt-Cl, Pt-S, and Pt-N stretch modes. The results also demonstrate that it is not possible to assign transition energies to "pure", localized modes in the low frequency region, as a consequence of the anticipated severe coupling that occurs among the skeletal modes. The use of INS has proved invaluable in identifying and assigning the modes in the lowest frequency region, and overall the results will be of assistance in analyzing the structure of the electronic excited state in the families of chromophores containing a Pt(diimine) core.
- Published
- 2012
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40. Syntheses and magnetic properties of Cr2Te3 and CuCr2Te4 nanocrystals.
- Author
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Ramasamy K, Mazumdar D, Bennett RD, and Gupta A
- Subjects
- Models, Molecular, Nanoparticles ultrastructure, Particle Size, X-Ray Diffraction, Chromium Compounds chemistry, Copper chemistry, Magnets chemistry, Nanoparticles chemistry, Tellurium chemistry
- Abstract
The Cr-based tellurides are attractive material systems for fundamental studies and potential applications. Colloidal syntheses of ferromagnetic Cr(2)Te(3) and CuCr(2)Te(4) nanocrystals with uniform morphology and narrow size distribution are reported together with their detailed magnetic characterisation.
- Published
- 2012
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41. Highly efficient visible-light driven photochromism: developments towards a solid-state molecular switch operating through a triplet-sensitised pathway.
- Author
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Brayshaw SK, Schiffers S, Stevenson AJ, Teat SJ, Warren MR, Bennett RD, Sazanovich IV, Buckley AR, Weinstein JA, and Raithby PR
- Abstract
We introduce a new highly efficient photochromic organometallic dithienylethene (DTE) complex, the first instance of a DTE core symmetrically modified by two Pt(II) chromophores [Pt(PEt(3))(2)(C≡C)(DTE)(C≡C)Pt(PEt(3))(2)Ph] (1), which undergoes ring-closure when activated by visible light in solvents of different polarity, in thin films and even in the solid state. Complex 1 has been synthesised and fully photophysically characterised by (resonance) Raman and transient absorption spectroscopy complemented by calculations. The ring-closing photoconversion in a single crystal of 1 has been followed by X-ray crystallography. This process occurs with the extremely high yield of 80%--considerably outperforming the other DTE derivatives. Remarkably, the photocyclisation of 1 occurs even under visible light (>400 nm), which is not absorbed by the non-metallated DTE core HC≡C(DTE)C≡CH (2) itself. This unusual behaviour and the high photocyclisation yields in solution are attributed to the presence of a heavy atom in 1 that enables a triplet-sensitised photocyclisation pathway, elucidated by transient absorption spectroscopy and DFT calculations. The results of resonance Raman investigation confirm the involvement of the alkynyl unit in the frontier orbitals of both closed and open forms of 1 in the photocyclisation process. The changes in the Raman spectra upon cyclisation have permitted the identification of Raman marker bands, which include the acetylide stretching vibration. Importantly, these bands occur in the spectral region unobstructed by other vibrations and can be used for non-destructive monitoring of photocyclisation/photoreversion processes and for optical readout in this type of efficiently photochromic thermally stable systems. This study indicates a strategy for generating efficient solid-state photoswitches in which modification of the Pt(II) units has the potential to tune absorption properties and hence operational wavelength across the visible range., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
- Published
- 2011
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42. Structure and ultrafast dynamics of the charge-transfer excited state and redox activity of the ground state of mono- and binuclear platinum(II) diimine catecholate and bis-catecholate complexes: a transient absorption, TRIR, DFT, and electrochemical study.
- Author
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Best J, Sazanovich IV, Adams H, Bennett RD, Davies ES, Meijer AJ, Towrie M, Tikhomirov SA, Bouganov OV, Ward MD, and Weinstein JA
- Subjects
- Catechols chemical synthesis, Crystallography, X-Ray, Electrochemistry, Models, Molecular, Molecular Structure, Organoplatinum Compounds chemical synthesis, Oxidation-Reduction, Spectrophotometry, Infrared, Time Factors, Vibration, Catechols chemistry, Organoplatinum Compounds chemistry, Quantum Theory
- Abstract
A series of mononuclear complexes of the type [Pt(Bu(2)cat)(4,4'-R(2)-bipy)] [where Bu(2)cat is the dianion of 3,5-(t)Bu(2)-catechol and R = H, (t)Bu, or C(O)NEt(2)] and analogous dinuclear complexes based on the "back-to-back" bis-catechol ligand 3,3',4,4'-tetrahydroxybiphenyl have been studied in detail in both their ground and excited states by a range of physical methods including electrochemistry, UV/vis/near-IR, IR, and electron paramagnetic resonance spectroelectrochemistry, and time-resolved IR (TRIR) and transient absorption (TA) spectroscopy. Density functional theory calculations have been performed to support these studies, which provide a detailed picture of the ground- and excited-state electronic structures, and excited-state dynamics, of these complexes. Notable observations include the following: (i) for the first time, the lowest-energy catecholate → bipyridine (bpy) ligand-to-ligand charge-transfer (LL'CT) excited states of these chromophores have been studied by TRIR spectroscopy, showing a range of transient bands associated with the bpy radical anion and semiquinone species, and back-electron-transfer occurring in hundreds of picoseconds; (ii) strong electronic coupling between the two catecholate units in the bridging ligand of the dinuclear complexes results in a delocalized, planar (class 3) "mixed-valence" catecholate(2-)/semiquinone(•-) state formed by one-electron oxidation of the bridging ligand; (iii) in the LL'CT excited state of the dinuclear complexes, the bridging ligand is symmetrical and delocalized, whereas the bpy radical anion is localized at one terminus of the complex. This study is the first example of an investigation of excited-state behavior in platinum(II) catecholate complexes, performed with the use of picosecond TRIR and femtosecond TA spectroscopy.
- Published
- 2010
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43. Kinetic analysis reveals differences in the binding mechanism of calmodulin and calmodulin-like protein to the IQ motifs of myosin-10.
- Author
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Caride AJ, Bennett RD, and Strehler EE
- Subjects
- Amino Acid Motifs genetics, Base Sequence, Calmodulin chemistry, Calmodulin genetics, Kinetics, Myosin Light Chains chemistry, Myosin Light Chains genetics, Myosin Light Chains metabolism, Myosins genetics, Protein Binding genetics, Protein Structure, Tertiary genetics, Proteins genetics, Proteins metabolism, Pseudopodia genetics, Pseudopodia metabolism, Calmodulin metabolism, Myosins chemistry, Myosins metabolism
- Abstract
Myo10 is an unconventional myosin with important functions in filopodial motility, cell migration, and cell adhesion. The neck region of Myo10 contains three IQ motifs that bind calmodulin (CaM) or the tissue-restricted calmodulin-like protein (CLP) as light chains. However, little is known about the mechanism of light chain binding to the IQ motifs in Myo10. Binding of CaM and CLP to each IQ motif was assessed by nondenaturing gel electrophoresis and by stopped-flow experiments using fluorescence-labeled CaM and CLP. Although the binding kinetics are different in each case, there are similarities in the mechanism of binding of CaM and CLP to IQ1 and IQ2: for both IQ motifs Ca(2+) increased the binding affinity, mainly by increasing the rate of the forward steps. The general kinetic mechanism comprises a two-step process, which in some cases may involve the binding of a second IQ motif with lower affinity. For IQ3, however, the kinetics of CaM binding is very different from that of CLP. In both cases, binding in the absence of Ca(2+) is poor, and addition of Ca(2+) decreases the K(d) to below 10 nM. However, while the CaM binding kinetics are complex and best fitted by a multistep model, binding of CLP is fitted by a relatively simple two-step model. The results show that, in keeping with growing structural evidence, complexes between CaM or CaM-like myosin light chains and IQ motifs are highly diverse and depend on the specific sequence of the particular IQ motif as well as the light chain.
- Published
- 2010
- Full Text
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44. Calmodulin-like protein upregulates myosin-10 in human keratinocytes and is regulated during epidermal wound healing in vivo.
- Author
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Bennett RD, Mauer AS, Pittelkow MR, and Strehler EE
- Subjects
- Calcium metabolism, Cell Differentiation, Cell Movement, Humans, Immunohistochemistry methods, Models, Biological, Wound Healing, Calmodulin metabolism, Epidermis metabolism, Gene Expression Regulation, Keratinocytes metabolism, Myosins biosynthesis, Skin metabolism, Up-Regulation
- Abstract
Epidermal wound healing is required for normal skin barrier function. Cell motility is a key factor in the ability of keratinocytes to heal epithelial damage. Calmodulin-like protein (CLP) is an epithelial-specific Ca(2+)-binding protein that is regulated during terminal keratinocyte differentiation. CLP is a specific light chain of unconventional myosin-10 (Myo10) and its expression increases filopodial length, filopodial number, and Myo10-dependent cell motility in vitro. However, the effects of CLP expression on keratinocyte motility are unknown. Here we used cultured human keratinocytes to study the role of CLP in regulating Myo10 and the effects of Myo10 and CLP on cell migration. CLP and Myo10 expression were correlated in vitro and required for keratinocyte motility in wound-healing assays. We examined the localization of CLP in wounded skin by immunohistochemistry and found an upregulation and peripheral localization of CLP in the basal and suprabasal cells adjacent to and immediately over the wound bed in vivo. The results suggest that increased CLP expression and CLP-mediated Myo10 function are important for skin differentiation and wound reepithelialization.
- Published
- 2009
- Full Text
- View/download PDF
45. Human calmodulin-like protein (CLP) expression in oral squamous mucosa and in malignant transformation.
- Author
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Brooks MD, Bennett RD, Strehler EE, Sebo TJ, Eckert SE, and Carr AB
- Subjects
- Calmodulin genetics, Cell Transformation, Neoplastic genetics, Double-Blind Method, Down-Regulation, Gene Expression Regulation, Neoplastic, Humans, Reverse Transcriptase Polymerase Chain Reaction, Calmodulin biosynthesis, Carcinoma, Squamous Cell metabolism, Cell Transformation, Neoplastic metabolism, Mouth Mucosa metabolism, Mouth Neoplasms metabolism
- Abstract
Purpose: The purpose of this study was to test whether calmodulin-like protein (CLP) is expressed in normal human oral mucosal cells and if downregulation of CLP occurs in malignant transformation., Materials and Methods: Oral mucosal tissue was taken from three individuals in a double-blind manner. The samples were cut, measured, and homogenized. Total RNA was extracted and reverse transcribed. Each cDNA sample was subjected to polymerase chain reaction (PCR). PCR fragments were purified, cloned, and sequenced to verify the presence of CLP. Three oral mucosal tissue samples with biopsy-confirmed squamous cell carcinoma were obtained. These samples demonstrated regions of normal epithelial cells as well as invasive squamous cell carcinoma. One normal breast epithelial sample was also obtained for positive control. Sections were stained with an affinity-purified CLP antibody and counterstained with a diluted hematoxylin. Two observers evaluated the specimens for expression of CLP. Staining patterns and intensity were noted in normal oral mucosa, comparing them to the normal breast epithelium sample. Staining patterns and intensity were then observed in squamous tumor cells, comparing them to the patterns of benign squamous mucosa., Results: CLP coding sequences were positively identified from the normal oral mucosal tissue samples by reverse transcription and polymerase chain reaction (RT-PCR) with 100% identity to the published CLP sequence (accession #M58026). In the three oral mucosa tissue samples with known squamous cell carcinoma, expression of CLP was readily detected in areas of normal oral mucosa, while a notable downregulation of CLP expression occurred in areas of malignant transformation. The staining intensity was equivalent to the staining seen in the benign breast epithelium used as a control. In the areas of squamous cell carcinoma, a decrease in CLP immunoreactivity occurred. There was a sharp contrast in staining quality and clarity between benign and malignant tissue. In the majority of the carcinoma regions, a complete lack of immunoreactivity was noted., Conclusions: The RNA for human CLP is found in normal oral mucosa. CLP expression is seen in normal oral mucosa with a downregulation of CLP expression in malignant transformation.
- Published
- 2009
- Full Text
- View/download PDF
46. Excited state dynamics of a PtII diimine complex bearing a naphthalene-diimide electron acceptor.
- Author
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Sazanovich IV, Alamiry MA, Best J, Bennett RD, Bouganov OV, Davies ES, Grivin VP, Meijer AJ, Plyusnin VF, Ronayne KL, Shelton AH, Tikhomirov SA, Towrie M, and Weinstein JA
- Abstract
A combination of picosecond time-resolved infrared spectroscopy, picosecond transient absorption spectroscopy, and nanosecond flash photolysis was used to elucidate the nature and dynamics of a manifold of the lowest excited states in Pt(phen-NDI)Cl 2 ( 1), where NDI = strongly electron accepting 1,4,5,8-naphthalene-diimide group. 1 is the first example of a Pt (II)-diimine-diimide dyad. UV/vis/IR spectroelectrochemistry and EPR studies of electrochemically generated anions confirmed that the lowest unoccupied molecular orbital (LUMO) in this system is localized on the NDI acceptor group. The lowest allowed electronic transition in Pt(phen-NDI)Cl 2 is charge-transfer-to-diimine of a largely Pt-->phen metal-to-ligand charge-transfer (MLCT) character. Excitation of 1 in the 355-395 nm range initiates a series of processes which involve excited states with the lifetimes of 0.9 ps ( (1)NDI*), 3 ps ( (3)MLCT), 19 ps (vibrational cooling of "hot" (3)NDI and of "hot" NDI ground state), and 520 mus ( (3)NDI). Excitation of 1 with 395 nm femtosecond laser pulses populates independently the (1)MLCT and the (1)NDI* excited states. A thermodynamically possible decay of the initially populated (1)MLCT to the charge-transfer-to-NDI excited state, [Pt (III)(phen-NDI (-*))Cl 2], is not observed. This finding could be explained by an ultrafast ISC of the (1)MLCT to the (3)MLCT state which lies about 0.4 eV lower in energy than [Pt (III)(phen-NDI (-*))Cl 2]. The predominant decay pathway of the (3)MLCT is a back electron transfer process with approximately 3 ps lifetime, which also causes partial population of the vibrationally hot ground state of the NDI fragment. The decay of the (1)NDI* state in 1 populates vibrationally hot ground state of the NDI, as well as vibrationally hot (3)NDI. The latter relaxes to form (3)NDI state, that is, [Pt(phen- (3)NDI)Cl 2]*, which possesses a remarkably long lifetime for a Pt (II) complex in fluid solution of 520 mus. The IR signature of this excited state includes the nu(CO) bands at 1607 and 1647 cm (-1), which are shifted considerably to lower energies if compared to their ground-state counterparts. The assignment of the vibrational bands is supported by the density-functional theory calculations in CH 2Cl 2. Pt(phen-NDI)Cl 2 acts as a modest photosensitizer of singlet oxygen.
- Published
- 2008
- Full Text
- View/download PDF
47. Interaction with the IQ3 motif of myosin-10 is required for calmodulin-like protein-dependent filopodial extension.
- Author
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Bennett RD, Caride AJ, Mauer AS, and Strehler EE
- Subjects
- Amino Acid Motifs, Amino Acid Sequence, Amino Acid Substitution, Binding Sites, Calmodulin antagonists & inhibitors, HeLa Cells, Humans, Molecular Sequence Data, Myosins genetics, Phenylalanine genetics, Protein Interaction Domains and Motifs, Protein Transport, Pseudopodia ultrastructure, Calmodulin metabolism, Myosins chemistry, Myosins metabolism, Pseudopodia metabolism
- Abstract
Calmodulin-like protein (CLP) is a specific light chain of unconventional myosin-10 (Myo10) and enhances Myo10-dependent filopodial extension. Here we show that phenylalanine-795 in the third IQ domain (IQ3) of Myo10 is critical for CLP binding. Remarkably, mutation of F795 to alanine had little effect on calmodulin binding to IQ3. Fluorescence microscopy and time-lapse video microscopy showed that HeLa cells expressing CLP and transiently transfected with GFP-Myo10-F795A exhibited significantly shorter filopodia and decreased intrafilopodial motility compared to wildtype GFP-Myo10-transfected cells. Thus, F795 represents a unique anchor for CLP and is essential for CLP-mediated Myo10 function in filopodial extension and motility.
- Published
- 2008
- Full Text
- View/download PDF
48. Calmodulin-like protein enhances myosin-10 translation.
- Author
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Bennett RD and Strehler EE
- Subjects
- HeLa Cells, Humans, Calmodulin metabolism, Myosins metabolism, Protein Modification, Translational physiology
- Abstract
Myosin-10 (Myo10) is involved in processes ranging from filopodial formation and extension to spindle orientation during cell division. Myo10 contains three IQ motifs that bind calmodulin and calmodulin-like protein (CLP) as light chains. We recently found that CLP expression up-regulates Myo10, leading to increased Myo10-dependent cell motility and filopodial extension [R.D. Bennett, et al., J. Biol. Chem. 282 (2007) 3205-3212]. CLP-dependent Myo10 up-regulation occurs without increase in Myo10 mRNA. We followed Myo10 degradation in vivo and in vitro and found that it was unaffected by CLP. Myo10 decayed rapidly with a half-life of approximately 2.5h. Using an in vitro transcription/translation system we determined that CLP increased Myo10 translation, resulting in a higher relative accumulation of Myo10 in the presence than in the absence of CLP. Our data suggest that CLP functions to increase translation of Myo10 possibly by acting as a chaperone for the emerging Myo10 heavy chain protein.
- Published
- 2008
- Full Text
- View/download PDF
49. Application of supramolecular nanostamping to the replication of DNA nanoarrays.
- Author
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Akbulut O, Jung JM, Bennett RD, Hu Y, Jung HT, Cohen RE, Mayes AM, and Stellacci F
- Subjects
- Gold chemistry, Metal Nanoparticles chemistry, Microscopy, Atomic Force, Microscopy, Scanning Tunneling methods, Molecular Conformation, Nanostructures, Nucleic Acid Conformation, Nucleic Acid Hybridization, Oligonucleotide Array Sequence Analysis instrumentation, DNA chemistry, Nanoparticles chemistry, Nanotechnology methods, Oligonucleotide Array Sequence Analysis methods
- Abstract
The rapid development of molecular biology is creating a pressing need for arrays of biomolecules that are able to detect smaller and smaller volumes of analytes. This goal can be achieved by shrinking the average size and spacing of the arrays' constituent features. While bioarrays with dot size and spacing on the nanometer scale have been successfully fabricated via scanning probe microscopy-based techniques, such fabrication methods are serial in nature and consequently slow and expensive. Additionally, the development of truly small arrays able to analyze scarce volumes of liquids is hindered by the present use of optical detection, which sets the minimum dot spacing on the order of roughly half the excitation wavelength. Here, we show that supramolecular nanostamping, a recently introduced truly parallel method for the stamping of DNA features, can efficiently reproduce DNA arrays with features as small as 14 +/- 2 nm spaced 77 +/- 10 nm. Moreover, we demonstrate that hybridization of these nanoarrays can be detected using atomic force microscopy in a simple and scaleable way that additionally does not require labeling of the DNA strands.
- Published
- 2007
- Full Text
- View/download PDF
50. Calmodulin-like protein increases filopodia-dependent cell motility via up-regulation of myosin-10.
- Author
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Bennett RD, Mauer AS, and Strehler EE
- Subjects
- Amino Acid Sequence, Base Sequence, Calmodulin genetics, Cell Division, DNA Primers, HeLa Cells, Humans, Molecular Sequence Data, Myosins genetics, Peptide Fragments chemistry, Reverse Transcriptase Polymerase Chain Reaction, Transfection, Calmodulin physiology, Cell Movement physiology, Myosins metabolism, Pseudopodia physiology
- Abstract
Human calmodulin-like protein (CLP) is an epithelial-specific protein that is expressed during cell differentiation but down-regulated in primary cancers and transformed cell lines. Using stably transfected and inducible HeLa cell lines, we found that CLP expression did not alter the proliferation rate and colony-forming potential of these cells. However, remarkable phenotypic changes were observed in CLP-expressing compared with control cells. Soft agar colonies of CLP-expressing cells had rough boundaries, with peripheral cells migrating away from the colony. Cells expressing CLP displayed a striking increase in the number and length of myosin-10-positive filopodia and showed increased mobility in a wound healing assay. This increase in wound healing capacity was prevented by small interference RNA-mediated down-regulation of myosin-10. Fluorescence microscopy and Western blotting revealed that CLP expression results in up-regulation of its target protein, myosin-10. This up-regulation occurs at the protein level by stabilization of myosin-10. Thus, CLP functions by increasing the stability of myosin-10, leading to enhanced myosin-10 function and a subsequent increase in filopodial dynamics and cell migration. In stratified epithelia, CLP may be required during terminal differentiation to increase myosin-10 function as cells migrate toward the upper layers and establish new adhesive contacts.
- Published
- 2007
- Full Text
- View/download PDF
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