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1.
J Biomed Mater Res A ; 111(9): 1322-1332, 2023 09.
Article in English | MEDLINE | ID: mdl-36924189

ABSTRACT

Hemocompatibility is the most significant criterion for blood-contacting materials in successful in vivo applications. Prior to the clinical tests, in vitro analyses must be performed on the biomaterial surfaces in accordance with the ISO 10993-4 standards. Designing a bio-functional material requires engineering the surface structure and chemistry, which significantly influence the blood cell activity according to earlier studies. In this study, we elucidate the role of surface terminations and polymorphs of SiC single crystals in the initial stage of the contact coagulation. We present a detailed analysis of phase, roughness, surface potential, wettability, consequently, reveal their effect on cytotoxicity and hemocompatibility by employing live/dead stainings, live cell imaging, ELISA and Micro BCA protein assay. Our results showed that the surface potential and the wettability strongly depend on the crystallographic polymorph as well as the surface termination. We show, for the first time, the key role of SiC surface termination on platelet activation. This dependency is in good agreement with the results of our in vitro analysis and points out the prominence of cellular anisotropy. We anticipate that our experimental findings bridge the surface properties to the cellular activities, and therefore, pave the way for tailoring advanced hemocompatible surfaces.


Subject(s)
Blood Coagulation , Platelet Activation , Biocompatible Materials/chemistry , Wettability , Surface Properties , Materials Testing , Platelet Adhesiveness
2.
Hand (N Y) ; 18(2): 250-253, 2023 03.
Article in English | MEDLINE | ID: mdl-34078170

ABSTRACT

BACKGROUND: Trigger finger is a common hand complaint of the general population. Limited literature exists implicating a low-estrogen state in patients on aromatase inhibitor (AI) therapy for breast cancer who develop trigger finger. The authors' objective was to determine the incidence and treatment outcomes of this population. METHODS: A single-center retrospective chart review was conducted on patients with a diagnosis of breast cancer on AI who developed trigger finger from 2010 to 2019. The total population of patients during this time served as our population, and patients with breast cancer not on AI with trigger finger served as our control. Primary outcomes included total number of injections and need for surgery. Secondary outcomes included risk factors for surgery. χ2 analysis and logistical regression model determined the significance of primary and secondary outcomes, respectively. RESULTS: In all, 192 patients of a population size of 664 751 met our study group criteria. The study group showed a higher incidence of trigger finger (5.1% vs 1.3%; P < .001) compared with our population. Patients treated with AI for breast cancer had both higher incidence of trigger finger (5.1% vs 1.5%, P < .001) and injections (77.1% vs 66.5%, P < .001) compared with patients not on AI therapy. Independent risk factors requiring surgical treatment were found in patients with diabetes (odds ratio [OR], 3.54; P = .01) and in patients with concomitant radiation therapy (OR, 3.17; P = .02). CONCLUSIONS: This study demonstrates for the first time the incidence, treatment outcomes, and surgical risk factors of trigger finger in patients on AI therapy for breast cancer.


Subject(s)
Breast Neoplasms , Trigger Finger Disorder , Humans , Female , Breast Neoplasms/drug therapy , Breast Neoplasms/chemically induced , Aromatase Inhibitors/adverse effects , Retrospective Studies , Trigger Finger Disorder/therapy , Trigger Finger Disorder/surgery , Incidence , Treatment Outcome
3.
Hand Clin ; 38(2): 199-205, 2022 05.
Article in English | MEDLINE | ID: mdl-35465937

ABSTRACT

Osteoarthritis of the first carpometacarpal joint is common. When nonoperative measures fail, surgery may provide long-term pain relief. There are many surgical options in the management of carpometacarpal joint arthritis. Trapeziectomy with hematoma arthroplasty is technically simple, inexpensive, and has withstood the test of time. It is an excellent option for advanced carpometacarpal joint arthritis with multiple high-quality studies showing equivalent outcomes between this technique and ligament reconstruction tendon interposition techniques. This article reviews trapeziectomy with hematoma arthroplasty for treatment of carpometacarpal joint arthritis, including the indications for the procedure, the authors' preferred technique, and the current literature.


Subject(s)
Carpometacarpal Joints , Osteoarthritis , Trapezium Bone , Arthroplasty/methods , Carpometacarpal Joints/surgery , Hematoma , Humans , Osteoarthritis/surgery , Thumb/surgery , Trapezium Bone/surgery
4.
Biophys J ; 121(10): 1909-1918, 2022 05 17.
Article in English | MEDLINE | ID: mdl-35421388

ABSTRACT

The gp16 ATPase is the constituent subunit of the pentameric dsDNA (double-stranded deoxyribonucleic acid) translocation motor of the Bacillus subtilis Φ29 bacteriophage. Although recent single-molecule studies have provided tantalizing clues about the activity of this motor, the mechanism by which the gp16 subunits couple the energy obtained from the binding and hydrolysis of ATP to the mechanical work of dsDNA translocation remains unknown. To address this need, we have characterized the binding of fluorophore-labeled ATP and ADP to monomeric gp16 using a stopped-flow fluorescence assay. These experiments show that the binding of ATP/ADP occurs through a single-step mechanism with corresponding affinities of 523.8 ± 247.3 nM for ATP and a lower limit of 30 µM for ADP. When analyzed through the lens of changes in free energy of the system, this difference in binding affinities is reasonable for a cyclical process of binding, hydrolysis, and product release. In addition to answering questions about the activity of monomeric gp16, these results are also a necessary step in constructing a model for intersubunit communication within the pentameric gp16 motor.


Subject(s)
Adenosine Triphosphatases , Bacillus Phages , Adenosine Diphosphate/metabolism , Adenosine Triphosphatases/metabolism , Adenosine Triphosphate/metabolism , Bacillus Phages/genetics , DNA, Viral/metabolism , Hydrolysis , Kinetics
5.
Cureus ; 14(1): e21428, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35103222

ABSTRACT

Headaches are a common presenting complaint to the emergency department. Amongst the common non-life-threatening headaches, migraine headaches tend to be one of the more severe. Commonly, migraines are treated with the so-called "migraine cocktail." At our facility, this cocktail is usually IV fluids, metoclopramide, diphenhydramine, and ketorolac. The patient is then left in a quiet, dark room for two to three hours, then reassessed for symptom improvement or if more medications are required. Recently we have begun to employ the sphenopalatine ganglion (SPG) block as a rapid, and easy-to-administer alternative to the classic migraine cocktail. The SPG block can often provide sufficient improvement of symptoms within 15 minutes to allow the patient to be discharged. Patients are grateful to have such rapid pain relief, and the ED flow is improved with a door-to-discharge time that can be less than an hour. The following is a series of three recent cases where we have used the SPG block to treat migraines in our ED patients.

7.
Hand (N Y) ; 16(6): NP15-NP18, 2021 11.
Article in English | MEDLINE | ID: mdl-33593099

ABSTRACT

Targeted muscle reinnervation (TMR) has been shown to improve phantom and neuropathic pain in both the acute and chronic amputee population. Through rerouting of major peripheral nerves into a newly denervated muscle, TMR harnesses the plasticity of the brain, helping to revert the sensory cortex back toward the preinsult state, effectively reducing pain. We highlight a unique case of an above-elbow amputee for sarcoma who was initially treated with successful transhumeral TMR. Following inadvertent nerve biopsy of a TMR coaptation site, his pain returned, and he was unable to don his prosthetic. Revision of his TMR to a more proximal level was performed, providing improved pain and function of the amputated arm. This is the first report to highlight the concept of secondary neuroplasticity and successful proximal TMR revision in the setting of multiple insults to the same extremity.


Subject(s)
Amputees , Phantom Limb , Amputation, Surgical , Humans , Male , Muscle, Skeletal , Upper Extremity/surgery
8.
Plast Reconstr Surg ; 147(2): 319-327, 2021 02 01.
Article in English | MEDLINE | ID: mdl-33165293

ABSTRACT

BACKGROUND: Anatomical studies have identified separate superficial and deep facial fat compartments, leading some to theorize that volume loss from the deep midface causes overlying superficial fat pseudoptosis. Unfortunately, a paucity of evidence exists regarding whether facial fat volume is truly lost with age and, if so, whether it is lost equally or differentially from the superficial and deep compartments. The aim of this study was to quantify volume changes occurring with age within the superficial, deep, and buccal fat compartments of the midface. METHODS: A retrospective longitudinal study was performed evaluating individuals aged 30 to 65 years who underwent facial computed tomography followed by facial computed tomography greater than or equal to 10 years later. Superficial midface, deep midface, and buccal fat volumes were quantified using Horos radiology software. RESULTS: Nineteen subjects met inclusion criteria. Mean total fat volume decreased significantly from 46.47 cc to 40.81 cc (p < 0.01). The mean superficial and deep fat volumes both decreased significantly from 26.10 cc to 23.15 cc (p < 0.01) and from 11.01 cc to 8.98 cc (p < 0.01), respectively. No significant difference was observed in buccal fat volume over time (9.36 cc to 8.68 cc; p = 0.04). Patients lost an average of 11.3 percent of their initial superficial fat volume and 18.4 percent of their initial deep fat volume. CONCLUSIONS: Significant volume loss was observed from both superficial and deep facial fat compartments over a mean 11.3 years. Patients lost a greater percentage of deep facial fat volume, providing support for the theory of pseudoptosis caused by deep midface fat loss.


Subject(s)
Aging/physiology , Face/anatomy & histology , Skin Aging/physiology , Subcutaneous Fat/anatomy & histology , Adult , Age Factors , Aged , Anatomy, Cross-Sectional , Face/diagnostic imaging , Face/physiology , Female , Humans , Longitudinal Studies , Male , Middle Aged , Retrospective Studies , Subcutaneous Fat/diagnostic imaging , Subcutaneous Fat/physiology , Tomography, X-Ray Computed
9.
Int J Mol Sci ; 22(1)2020 Dec 23.
Article in English | MEDLINE | ID: mdl-33374740

ABSTRACT

The packaging of the eukaryotic genome into chromatin regulates the storage of genetic information, including the access of the cell's DNA metabolism machinery. Indeed, since the processes of DNA replication, translation, and repair require access to the underlying DNA, several mechanisms, both active and passive, have evolved by which chromatin structure can be regulated and modified. One mechanism relies upon the function of chromatin remodeling enzymes which couple the free energy obtained from the binding and hydrolysis of ATP to the mechanical work of repositioning and rearranging nucleosomes. Here, we review recent work on the nucleosome mobilization activity of this essential family of molecular machines.


Subject(s)
Chromatin Assembly and Disassembly , Chromosomal Proteins, Non-Histone/metabolism , Nucleosomes/metabolism , Transcription Factors/metabolism , Adenosine Triphosphate/metabolism , Animals , Chromosomal Proteins, Non-Histone/chemistry , Humans , Nucleosomes/chemistry , Protein Conformation , Protein Stability , Transcription Factors/chemistry
10.
Phys Rev E ; 97(3-1): 032422, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29776169

ABSTRACT

Chromatin remodelers are molecular motors that play essential roles in the regulation of nucleosome positioning and chromatin accessibility. These machines couple the energy obtained from the binding and hydrolysis of ATP to the mechanical work of manipulating chromatin structure through processes that are not completely understood. Here we present a quantitative analysis of nucleosome repositioning by the imitation switch (ISWI) chromatin remodeler and demonstrate that nucleosome stability significantly impacts the observed activity. We show how DNA damage induced changes in the affinity of DNA wrapping within the nucleosome can affect ISWI repositioning activity and demonstrate how assay-dependent limitations can bias studies of nucleosome repositioning. Together, these results also suggest that some of the diversity seen in chromatin remodeler activity can be attributed to the variations in the thermodynamics of interactions between the remodeler, the histones, and the DNA, rather than reflect inherent properties of the remodeler itself.


Subject(s)
Biocatalysis , Models, Biological , Nucleosomes/metabolism , DNA/genetics , DNA/metabolism , DNA Damage
12.
J Craniofac Surg ; 27(8): e785-e787, 2016 Nov.
Article in English | MEDLINE | ID: mdl-28005824

ABSTRACT

Craniofacial clefts are rare entities, with an incidence reported as 1.43 to 4.85 per 100,000 births. The Tessier number 3 cleft, the most medial of the oblique clefts, can manifest as clefting of the lip between the canine and lateral incisors, colobomas of the nasal ala and lower eyelid, and inferior displacement of the medial canthus-frequently disrupting the lacrimal system with extreme variability in expressivity (Eppley).Literature on cleft lip repair is extensive and has evolved to incorporate anthropometric techniques, based on identifiable landmarks and anthropometric measurements that are compared with contralateral unaffected anatomy or population means and tracked over time to assess impact on growth. Recent focus has been placed on "subunit" repair that repairs "like with like." These approaches have resulted in a remarkable reproducibility of methods and outcomes.Facial cleft surgery publications are sparse due to the rarity of the disorders, and consensus has yet to develop on standardized landmarks, reference measurements, and principles of repair. The authors describe a method of correcting incomplete unilateral Tessier 3 cleft based on the principles described above. Intraoperative photographs, including secondary revisions, as well as immediate and long-term postoperative results are presented.


Subject(s)
Abnormalities, Multiple/surgery , Cleft Lip/surgery , Coloboma/surgery , Craniofacial Abnormalities/surgery , Eyelids/abnormalities , Nose/abnormalities , Plastic Surgery Procedures/methods , Abnormalities, Multiple/diagnosis , Anthropometry , Child , Child, Preschool , Cleft Lip/diagnosis , Coloboma/diagnosis , Craniofacial Abnormalities/diagnosis , Eyelids/surgery , Humans , Infant , Male , Nose/surgery , Treatment Outcome
13.
J Craniofac Surg ; 24(3): 917-22, 2013 May.
Article in English | MEDLINE | ID: mdl-23714911

ABSTRACT

BACKGROUND: Traditional reconstructive options for cranial defects include autogenous bone graft, bone substitutes, and synthetic materials. The established standard for repairing cranial defects is autogenous bone. However, young children do not have abundant donor sites for bone harvest, which leads to challenges in closing calvarial defects. Synthetic materials are not ideal alternatives because they require subsequent retrieval and are prone to infection. Their long-term effects on growth of the skull are also not well studied. Bone morphogenetic protein 2 (BMP-2), are shown to positively affect closure of cranial defects in animal models. We present a study comparing the efficacy and safety of closure of cranial defect with bone graft augmented with recombinant human BMP-2 (rhBMP-2) and compared with a series of patients treated with bone graft alone. METHODS: This study is a retrospective multicenter evaluation of 36 patients spanning 5 years. Twenty-one patients undergoing cranial defect closure augmented with rhBMP-2 were compared with 15 patients who underwent cranial defect closure using cranial bone shavings alone. We measured preoperative and postoperative defect size on volumetric computed tomographic scan reconstructions to compare defect sizes. RESULTS: The rhBMP-2 group had slightly increased proportional closure compared with the control group, 86% versus 76% (P < 0.018), respectively. Two patients in the rhBMP-2 group had postoperative fusion of a suture that was known to be patent at the time of cranial defect closure. No instances of brain edema, herniation, airway compromise, or other adverse effects directly attributable to rhBMP-2 were observed. CONCLUSIONS: Bone morphogenetic protein 2 may increase the amplitude and uptake of cranial bone grafts in cranial defect closure. This study shows that defect sizes of up to 16 cm can be reliably closed using this technique. Postoperative fusion of uninvolved sutures in 2 patients indicates that rhBMP-2 may have unreported adverse effects; consideration of this finding should be weighed against the benefit of improved closure of calvarial defects.


Subject(s)
Bone Diseases/surgery , Bone Morphogenetic Protein 2/therapeutic use , Plastic Surgery Procedures/methods , Skull/surgery , Transforming Growth Factor beta/therapeutic use , Absorbable Implants , Adolescent , Autografts/transplantation , Bone Transplantation/methods , Child , Child, Preschool , Collagen , Drug Carriers , Female , Follow-Up Studies , Frontal Bone/surgery , Humans , Male , Occipital Bone/surgery , Parietal Bone/surgery , Recombinant Proteins/therapeutic use , Retrospective Studies , Safety , Tomography, X-Ray Computed/methods , Treatment Outcome
15.
Anal Chem ; 84(21): 9609-14, 2012 Nov 06.
Article in English | MEDLINE | ID: mdl-23061696

ABSTRACT

The pressure output of a pump cannot be increased simply by connecting several of them in series. This barrier is eliminated with the micropump developed in this work. The pump is actually an assembly of a number of fundamental pump units connected in series. The maximum pressure output of this pump assembly is directly proportional to the number of serially connected pump units. Theoretically, one can always enhance the pressure output by adding more pump units in the assembly, but in reality the upper pressure is constrained by the microtees or microunions joining the pump components. With commercially available microtees and microunions, pressures of more than 1200 bar have been achieved. We have recently experimented using open capillaries to build this pump, but many capillaries have to be utilized in parallel to produce an adequate flow to drive HPLC separations. In this paper, we synthesize polymer monoliths inside 75 µm i.d. capillaries, use these monoliths to assemble miniaturized pumps, characterize the performance of these pumps, and employ these pumps for HPLC separations of intact proteins. By tuning the experimental parameters for monolith preparations, we obtain both negatively and positively charged submicrometer capillary channels conveniently. Each monolith in a 75 µm i.d. capillary is equivalent to several thousands of open capillaries.

16.
Int J Dermatol ; 51(4): 383-8, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22435424

ABSTRACT

Cutaneous involvement by myeloid leukemic cells is an unusual phenomenon. Clinical manifestations vary from erythematous papules to plum-colored plaques and nodules that may become purpuric and ulcerate. The definitive diagnosis of myeloid leukemia cutis requires the analysis of biopsy specimens using immunohistochemical staining to determine the expression of selective cell surface markers. We will review myeloid leukemia when first evident in the skin, particularly in the setting of myelodysplastic syndrome. The diagnosis of leukemia cutis in patients with myelodysplastic syndrome is indicative of concomitant or impending acute leukemic transformation. The early recognition and accurate identification of leukemic skin infiltrates in myelodysplastic patients is crucial, as this finding can have significant therapeutic and prognostic implications.


Subject(s)
Leukemia, Myeloid, Acute/diagnosis , Myelodysplastic Syndromes/complications , Skin Diseases/diagnosis , Cell Transformation, Neoplastic , Diagnosis, Differential , Humans , Leukemia, Myeloid, Acute/complications , Prognosis , Skin Diseases/complications
17.
Cutis ; 87(5): 221-5, 2011 May.
Article in English | MEDLINE | ID: mdl-21699121

ABSTRACT

Symptomatic dermatographism reflects an exaggerated cutaneous response to the physical stimulus of pressure. Some consider it a common type of childhood physical urticaria. Its etiology can vary widely from drug reactions and infectious agents to systemic diseases and genetic inheritance. The mechanism is thought to be related to histamine degranulation due to a mechano-immunologic trigger, leading to the common symptoms of pruritus and burning in areas exposed to increased pressure, such as tight clothing, belts, and waistbands. The diagnosis typically is made with a blunt object such as a tongue blade or unopened ball-point pen pressed along the back and/or forearm, which elicits urtication. The mainstay of treatment is H1- and H2-receptor antagonists but also can include immunosuppressive agents, steroids, and phototherapy for refractory or severe cases.


Subject(s)
Pressure , Skin Diseases/etiology , Urticaria/etiology , Child , Histamine/metabolism , Histamine H1 Antagonists/pharmacology , Histamine H2 Antagonists/pharmacology , Humans , Physical Stimulation/adverse effects , Skin Diseases/pathology , Skin Diseases/therapy , Urticaria/therapy
18.
Environ Toxicol Chem ; 30(6): 1243-51, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21337609

ABSTRACT

Endocrine disruptors cause adverse health effects as a result of their ability to shift the hormonal balance that is essential to the body. Bisphenol A (BPA) is an endocrine disruptor that has garnered much attention because of its presence in many consumer materials, which generates a significant risk for exposure. A method is presented for rapid detection of oral exposure to BPA directly from human saliva. Saliva was chosen because it serves as a noninvasive sampling route to detect BPA exposure; however, it is one of many complex biological matrices that have traditionally posed problems in quantitative analysis. Such analyses usually require extensive sample preparation to reduce interferences contributed by the sample matrix. Three validated methods are presented here that feature a streamlined sample-preparation strategy (bulk derivatization) prior to accurate and sensitive analysis by trap-and-elute liquid chromatography coupled to electrospray ionization mass spectrometry. Validated methods include standard addition calibration with variable injection volumes and multiple injection loading, as well as with incorporation of an internal standard. Reported limits of detection reached as low as 49.0 pg/ml (2.9 pg loaded on-column; equivalent to parts per trillion in saliva) among the presented methods with good accuracy and precision throughout. A proof-of-concept study is demonstrated to show that the final validated method has potential application to specific studies for trace-level BPA detection from real samples.


Subject(s)
Endocrine Disruptors/analysis , Phenols/analysis , Saliva/chemistry , Anabasine/analysis , Benzhydryl Compounds , Calibration , Chromatography, Liquid/methods , Environmental Exposure/analysis , Humans , Limit of Detection , Reference Standards , Spectrometry, Mass, Electrospray Ionization
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