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Comparative investigations on environmentally triggered drug delivery and wound healing characteristics of flexible hydrogel composites, Chitosan-Gelatin (C/G) and 2-Hydroxyethyl Methacrylate-Gelatin (H/G); are presented here. These composites, prepared through facile synthesis and curing methods, indicate the potential to smartly respond to the pH changes in wounds by releasing drug simultaneously and aiding in faster healing. An in-vitro investigation of the composite characteristics were included testing for Equilibrium Water Capacity Studies, Fourier Transform Infrared Spectroscopy (FTIR) investigations as well as UV based drug release and gravimetric hydrogel degradation profiles. This was followed by cutaneous application testing of the hydrogel systems in balb-c mice. Observations and testing results indicated the potential applicability of the hydrogel systems as dressings for topical/transdermal applications, provided that further detailed in-vivo characteristics are accounted for.

Purpose The purpose of this paper is to present synthesis protocol of hydrogel composed of Chitosan (CS) and Poly(ethylene glycol) (PEG) and establish an understanding of its thermal responsive behavior. It aims to prove the basic temperature sensing ability of a novel CS-PEG-based hydrogel and define its sensing span. Design/methodology/approach This study includes synthesis of CS and PEG-based hydrogel samples by first performing dissolution of both constituents, respectively, and then adding Glutaraldehyde as the cross-linking agent. It further includes proposed hydrogel’s swelling studies and dynamic behavior testing, followed by hydrogel characterization by Fourier transform infrared spectroscopy, X-ray diffraction and SEM. The last section focuses on the use of proposed hydrogel as a temperature sensor. Findings Detailed experimental results show that a hydrogel comprising of CS and PEG presents a thermally responsive behavior. It offers potential to be used as a temperature responsive hydrogel-based sensor which could be used in medical applications. Originality/value This research study presents scope for future research in the field of thermally responsive bio-sensors. It provides basis for the fabrication of a thermal responsive sensor system based on hydrogels that can be used in specific medical applications.

Objectives: The objectives of the study were to evaluate the vascular and tissue response of Pakistani manufactured novel drug eluting stent (called N-DEAVOUR®) on a swine model and compare the results with XIENCE PRO™. Methodology: A total of 10 animals were used for the study and assigned randomly to each time-point group. The test articles were administered percutaneously and each animal was implanted with one stent in each one of the coronary arteries (3 in total) LCA (left circumflex artery), LAD (left anterior descending coronary artery), and RCA (right coronary artery). Additionally, a second test stent was implanted in some animals (4 in total). QCA (Quantitative Coronary Angiography) technique was used for measurements of the vessel at the target site. OCT (Optical Coherence Tomography) was performed only at follow up time-points which were 30, 90 and 180 days. Results: At 30 DFU, parameters for N-DEAVOUR® were comparable to those of both control (XIENCE PROTM and VISION) stents. At 90 days follow-up N-DEAVOUR® showed no statistically significant difference in performance for values of lumen area, stent area, area stenosis, and neointimal area against XIENCE PRO™. With reference to stent area, at 90 DFU, N-DEAVOUR® performed better than XIENCE PRO™ (p=0.0056). For neo-intimal area, area stenosis and lumen area, the differences between XIENCE PRO™ and N-DEAVOUR® were non-significant (p=0.13; p=0.9; p=0.086) respectively. These results indicate the positive potential of N-DEAVOUR® to be successfully implanted in clinical settings after necessary randomized clinical trials are executed. Conclusion: This study proved that the drug eluting stent examined in the present study is both safe and feasible. This study supports that this stent can move forward for human trials.

High fluoride levels in groundwater used for drinking have caused health concerns for millions of people across the world. Pakistan is one of the countries that have been contaminated by these toxins. However, a little amount of fluoride is required for tooth and bone strength. In any event, the presence of too much of it in drinking water can cause diseases in both people and animals. This study is focused on the synthesis of bio-adsorbent bone char to adsorbent for the removal of fluoride from groundwater obtained from Islamkot district Tharparkar. The bone char was synthesized by pyrolysis of used cow bones at a temperature of 550 degrees C. The fluoride removal efficiency of bone char was optimized. The impacts of different operating parameters such as flow rates (5mL/min, 10mL/min, and 15mL/min), bed height of adsorbent (2cm, 4cm, and 6cm), initial fluoride concentration 7.85 mg/L, and contact time (30min, 60min, and 90min) were studied. The removal efficiency was enhanced by increasing the adsorbent bed height and decreasing contact time and flow rate. With an initial concentration of fluoride 7.85mg/L, the maximum removal efficiency of 90.2% was obtained when the adsorbent bed height, flow rate, and contact time were optimized to 6 cm, 5 mL/min, and 30min, respectively. The finding showed that bone char can be used as an eco-friendly, inexpensive, and efficient adsorbent for removing fluoride from groundwater.

Objectives: The aim of this pilot study was the first-in-man evaluation of the safety, feasibility, deliverability, and efficiency of the newly developed REJUVENATE® bare metal stent system in coronary artery disease. Methodology: Current study was a pilot non-randomized, multi-centric and prospective study which was intended to study the safety of the REJUVENATE® bare metal stent in Pakistani population over 10 months. Study endpoints included target vessel related myocardial infarction, stent thrombosis, in-stent restenosis, stroke and death. The diameter of the target lesions selected was between 3-4mm with length no more than 22mm. Only one BMS was implanted per patient. These patients had well defined regular clinical follow-ups and CT scan coronary angiography at the end of 10 months. Results: 20 patients suffering from coronary artery disease (CAD) including15 male subjects and 5 female subjects were enrolled in this study and were treated with REJUVENATE® BMS. 65% patients were hypertensive, 25% diabetics and 25% were active smokers. Out of the 20 stents implanted, 14 stents were implanted in the right coronary artery and 6 were implanted in the left circumflex artery. During this 10-month study period there was 10.65% of cases in which late lumen loss (lumen stenosis

Wound treatment remains a challenge to many clinicians because of the complexities of the wound healing process. With the astonishing progress of biomedical engineering during the past few decades, conventional drug delivery systems have been evolved into smart drug delivery systems with stimuli-responsive characteristics. The objective of this study was to develop and evaluate an electromechanically actuated drug dispensation device which can release active pharmaceutical compound in a controlled fashion. Additive manufacturing was employed to design and fabricate the device. Haptic technology was used to provide stimulation for drug release, and Cicatrin was used to evaluate the drug release patterns of device. Drug release study was comprised of in vitro drug release, static study, and the purpose of this study was to develop a compliance chart for different wound conditions. The effectiveness of shortlisted drug regimen from compliance chart was validated through microbial study and animal studies. The results of animal studies were compared with commercially available drug release systems. The results of drug release studies gave different dose regimens for different wound conditions. The effective dose regimen was able to create 1-cm-wide microbial zone of inhibitions. The wound healing rate of mice for commercially available release system for five consecutive days was 10%, 10%, 20%, 40% and 50% and for test device was 10%, 30%, 60%, 90% and 100%. Hence, the device proved its effectiveness and efficacy of dosage regimen for wound healing applications through in vitro, microbial and in vivo studies. In conclusion, this device proved to be an accurate and specific drug delivery system with improved medication and therapeutic outcomes for personalized medication.

In-situ monitoring and post-process metrology form a basis to better understand the fundamental physics involved in the Laser Powder Bed Fusion (LPBF) process and ultimately to determine its stability. By utilizing high-speed imaging, various process signatures are produced during single track formation of 316L stainless steel with various combinations of laser power and scan speed. In this study, we evaluate whether these signatures can be used to detect the onset of potential defects. To identify process signatures, image segmentation and feature detection are applied to the monitoring data along the line scans. The process signatures determined in the current study are mainly related to the features like the process zone length-to-width ratio, process zone area, process zone mean intensity, spatter speed and number of spatters. It is shown that the scan speed has a significant impact on the process stability and spatter formation during single track fusion. Simulations with similar processing conditions were also performed to predict melt pool geometric features. Post-process characterization techniques such as X-ray computed tomography and 2.5-D surface topography measurement were carried out for a quality check of the line track. An attempt was made to correlate physics-based features with process-related defects and a correlation between the number of keyhole porosities and the number of spatters was observed for the line tracks.

Objectives: The main objective of the study was to evaluate the implantation, safety, and vascular tissue effects of REJUVENATE® Cobalt Chromium Bare Metal Stent in the Porcine Coronary Restenosis model at short, mid and long-term follow up. Methodology: A total of 18 REJUVENATE® bare metal stents (CoCr, 95 µm strut thickness) were implanted into the coronary arteries (RCA, LCX and LAD) of the six pigs. Throughout the study period, stent patency, vascular response, percent stenosis, late lumen loss and performance of stent were evaluated by angiography, optical coherence tomography (OCT), and Histopathology (includes both Histopathology and histomorphometry) at 30, 90, and 180 days and compared with the results of control Bare Metal Stent Coflexus®. The mean, variance and standard deviation was analyzed using SPSS software. Results: OCT and QCA analysis demonstrated two cases of binary restenosis at 30 days follow-up and two at 90 days follow-up (33%). The mean area stenosed for Rejuvenate® was 34% as compared to 24% of Coflexus® and at 180 days follow up, it decreased to 21%. The histopathology analysis demonstrated favorable safety with acceptable levels of neointimal formation, with decreased levels of inflammation and complete endothelialization in 180 days. Conclusion: This study proved the potential safety of REJUVENATE® in porcine model and supports that this stent can move forward for the human trials.

AimsTouch preparation (TP) and frozen section (FS) are the two methods routinely used in the intraoperative evaluation (IOE) of sentinel lymph nodes (SLNs) to detect metastases in patients with breast cancer. Both methods are extremely sensitive and specific in the primary surgery (non-neoadjuvant systemic therapy (non-NST)) setting. Since NST introduces unique challenges in the IOE of SLNs, the aim was to determine the accuracy of TP and FS in the IOE of SLNs in the NST setting and compare the results with the non-NST setting and to examine factors that contribute to any differences.MethodsWe analysed 871 SLNs from 232 patients (615 SLNs from NST and 256 SLNs from non-NST settings) between 2016 through 2019.ResultsIn the NST group, TP alone (n=366) had a sensitivity of 45.7% and specificity of 99.7%; FS alone (n=90) had a sensitivity of 83.3% and specificity of 100%. When both TP and FS (n=135) were used, the sensitivity was 80.3% and the specificity was 98.6%.In the non-NST group, TP alone (n=193) had a sensitivity of 66.7% and specificity of 100%; FS alone (n=22) had a sensitivity and specificity of 100%; and combined TP and FS (n=34) had a sensitivity and specificity of 100% and 96%, respectively.ConclusionsEvaluating SLNs intraoperatively in the NST setting can be challenging secondary to therapy-related changes. In the NST setting, FS has higher sensitivity and specificity compared with TP for the IOE of SLNs and should be the preferred method.

Case Presentation A 54-year-old woman was admitted to the general medical floor after undergoing percutaneous nephrolithotomy via the supracostal approach. On postprocedure day 1, she developed low-grade fever, dry cough, shortness of breath, and palpitations.

PurposeThe fabrication and characterization of a hydrogel-based conductometric sensor have been carried out. The purpose of this research is to fabricate a small robust hydrogel-based conductometric sensor for real-time monitoring of pH in the physiological range.Design/methodology/approachA pH-responsive Chitosan/Gelatin composite hydrogel has been used for this purpose. This study reports and analyzes the sensing response obtained from four hydrogel compositions with varying Chitosan/Gelatin ratios. The pH-responsive nature of the hydrogel has been mapped out through volumetric and conductometric tests. An attempt has been made to correlate these characteristics with the physico-chemical nature of the hydrogel through scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction techniques.FindingsThe four hydrogel compositions differed on the basis of gel composition ratios; the conductometric analysis results prove that the sensor with the hydrogel composition (Chitosan 2 per cent, Gelatin 7 per cent, ratio 1:2) produces the best pH resolution in the pH range of 4 to 9. The sensing mechanisms and the differences obtained between individual sensor outputs have been discussed in detail. On the basis of this extensivein vitroassessment, it has been concluded that while key pendant functional groups contribute to pH-responsive characteristics of the hydrogel, the overall sensitivity of the sensors gel component to surrounding pH is also determined by the crystalline to amorphous ratio of the hydrogel composite, its interpenetrating cross-linked structure and the relative ratio of the hydrophilic to the pH-sensitive components.Practical implicationsThe conductometric sensor results prove that the fabricated sensor with the shortlisted hydrogel composition shows good sensitivity in the physiological pH range (4 to 9) and it has the potential for use in point of care medical devices for diagnostic purposes.Originality/valueThis is the first reported version of the fabrication and testing and analysis/comparison of a hydrogel-based conductometric sensor based on this composition. The work is original and has not been replicated anywhere.

Introduction The recommendation for reporting benign-appearing endometrial cells in Papanicolaou specimens was increased from 40 to 45 years in the 2014 edition of The Bethesda System. Recent studies suggest that increasing the reporting age to 50 years would have no significant negative impact. Reporting of benign endometrial cells may trigger unnecessary procedures and increase the cost of patient care. The goal of our study was to perform cytohistologic correlations and determine an optimal age cutoff for reporting endometrial cells in cervical cytology specimens. Materials and methods The pathology database was searched between 2006 and 2015 for Papanicolaou tests with benign-appearing endometrial cells that were followed by endometrial sampling within 1 year of the cytology result in women ≥45 years. In cases where more than one follow-up surgical specimen was available, only the most significant result was included. Endometrial carcinoma or atypical hyperplasia was considered a significant histologic result. The data were organized into 4 age groups, 45 to 49, 50 to 54, 55 to 59, and ≥60 years. Results Among 453,420 Papanicolaou specimens, 1121 cases reported endometrial cells in women ≥45 years. Of these, 588 (52%) had an endometrial biopsy/curettage or hysterectomy. Benign diagnosis was reported for 558 (95%) and 12 (2%) samples were insufficient for diagnosis. Significant histologic findings were present in 18 (3%) of cases, of which all were endometrial carcinoma. The difference was statistically significant between the age groups 45 to 54 and ≥55 (1.5% versus 17% of cases had significant endometrial pathology, P Conclusions Increasing the current reporting age appears safe and may improve efficiency and cost savings.

Anomalous origin of right coronary artery (ARCA) arising from the left sinus of Valsalva (a congenital cardiac abnormality) and sinus of Valsalva aneurysm (SOVA) are rare and often have asymptomatic conditions. However, symptoms could range from chest pain, shortness of breath, palpitations, syncope to sudden cardiac death (SCD). The co-existence of these two anomalies (ARCA + SOVA) could lead to potential adverse outcomes in the absence of early intervention. The presence of these two conditions together increases the risk of SCD as reported in our case of a young male who presented to the emergency department with chest pain.

Drug delivery systems (DDSs) are a promising avenue for targeted drug delivery over a given time frame. Different techniques have been devised for drug encapsulation in a delivery system which can carry it to the target site and release it as a function of time. The biochemical properties of encapsulation systems are tailored according to the required release profile for the target tissue. Electrospun fibers have been greatly investigated recently for the development of DDSs. Different applications for specific fiber types have been fabricated and tested in order to determine their clinical significance. This review critically analyzes the potential applications of electrospun fibers in drug delivery system (DDS).

Anterior cruciate ligament (ACL), a structure involved in providing knee stability, is an important restraint for anterior tibial translation and secondary restraint for internal tibial rotation. Injury to ACL, leading to its rupture can cause a lot of problems such as effect on knee stability, cartilage wear and other joint structures. Understanding the anatomy, physiology and the mechanical behavior is important as it helps in the understanding of its function and healing capacity after injury. This review takes a brief look at the anatomy, physiology and mechanical behavior of ACL. The causes of injury and healing process of ACL have also been discussed. This review gives an overview of the surgical treatment options for ACL rupture. These treatment options include methods that have been abandoned like primary repair, methods that are currently in use like the biological grafts and prosthetic grafts that are no longer being used (except LARS which is currently not used widely) due to the complications associated with them. Non-surgical, conservative treatment options for ACL have also been discussed.

Background Auxetic materials tend to exhibit stretching in the direction of the applied load as well as in the perpendicular direction. This may be an inherent property of the material, or it might be a particular structural characteristic that confers it with auxetic properties. In this study, the auxetic properties of a rotating squares auxetic design were utilized in tandem with a stretching mechanism to manufacture a device that offers the advantages of adjustable pore size and hence tunable drug delivery characteristics. Methods An auxetic polyurethane film was fabricated through the polymer casting technique. An acrylonitrile-butadiene-styrene (ABS) plastic mold for polymer casting was made through additive manufacturing. Stereolithography was used for fabrication of the mechanism that controlled pore size of the polymeric auxetic film. A laminate arrangement of the film and the mechanism was devised, through which movement of the mechanism controlled stretching of the auxetic film underneath. Results Results were analyzed through image processing. It was observed that a 2-dimensional increase (in length and width) of the auxetic film took place that corresponded to an increase in pore size of the film. Several mathematical correlations were drawn up. Conclusions It may be concluded that the first factor controlling drug release kinetics is the pore size of the film. This study explored a prototype mechanism that has the potential for being used in devices for controlled drug delivery or in smart bandage systems that may enhance wound healing in chronic wound treatment.

The design and fabrication of a wound healing device for chronic wounds, with multiple functions for controlled drug delivery and exudate removal, has been described in this paper. The structural features have been machined and modified through laser cutting in a biocompatible polymer cast. Miniaturized versions of electronically actuated (lead-screw and pulley) mechanisms are used for the specific purpose of controlled drug delivery. These mechanisms have been studied and tested, being controlled through a microcontroller setup. An auxetic polymeric barrier membrane has been used for restricting the drug quantities administered. Drug delivery mechanisms are powered wirelessly, through an external, active RF component; this communicates with a passive component that is buried inside the wound healing device. The exudate removal efficiency of the device has been assessed through several simple tests using simulated wound exudate. It has been found that reasonably precise quantities of drug dosages to be administered to the wound site can be controlled through both drug delivery mechanisms; however, the lead-screw mechanism provides a better control of auxetic barrier membrane actuation and hence controlled drug delivery. We propose that this device can have potential clinical significance in controlled drug delivery and exudate removal in the management of chronic wounds., Application of rotating squares auxetic geometry in precisely controlled drug delivery for potential use in wound management systems; a comparison between two electromechanically controlled mechanisms employing the auxetic rotating squares geometry.

Background Auxetics, a special class of materials, tend to expand both in the radial and longitudinal directions when a unidirectional tensile force is applied. Recently, studies have come up with new designs for auxetic vascular and nonvascular stents which are deployed with commercial balloon catheters. There are some inherent limitations associated with a unidirectional application of expansion force in the effective deployment of stents. This work proposed a solution to some of these limitations through the use of a biaxial mode of a predetermined strain-based expansion mechanism. Method The design incorporated a pressure-activated crank-slider mechanism. Fabrication of a prototype for experimental verification was carried out through milling and high-speed lathe machining. The testing of the device employed the use of auxetic stents, fabricated from a biocompatible polymer. A finite element study is presented to extrapolate experimental results to a broader range of operation and working conditions. Results and Conclusions The expansion mechanism is similar in operation to the opening of an umbrella. The length of the connected auxetic stent increases when internal hydraulic pressure is applied. The degree of linear expansion in 1 direction influences the expansion of auxetic stent in the lateral direction. As the device exerts pressure longitudinally, a larger amount of the force is distributed on the unit cells/hinges which ultimately results in an increased expansion of the stent.

Metastatic prostate cancer and multiple myeloma (MM) usually present with bone lesions, posing a diagnostic challenge in males presenting in late stages. In this case report, an 86-year-old male who had not seen a physician in over 30 years presented with complaints of hip pain and progressive difficulty in walking for three weeks. Outpatient X-ray of the right hip showed multiple lytic bone lesions, raising suspicion of MM. Other laboratory tests revealed elevated serum calcium and elevated prostate-specific antigen (PSA), supporting a diagnosis of prostate cancer. The patient was admitted for further workup. Magnetic resonance imaging (MRI) of the spine showed diffuse metastatic disease throughout the spine as well as pelvis with multilevel central canal and neuro-foraminal narrowing due to degenerative changes. Central canal narrowing at L1-L2 due to tumor involvement could not be ruled out on MRI. Subsequently, urology was consulted and the patient was taken to the operating room for prostate biopsy and possible bilateral orchiectomy. Two intraoperative prostate biopsies were negative for malignancy but patient underwent bilateral orchiectomy due to high clinical suspicion for prostate cancer. Bone lesions in the pelvis were so extensive that orthopedic surgeons recommended complete non-weight bearing as the risk of fracture with weight bearing was thought to be very high. Eventually, laboratory workup for MM came out to be positive. Radiation oncologist recommended radiation therapy; however, at this point, the patient refused further intervention. He opted for palliative care. Consequently, a bone marrow biopsy could not be obtained for a definitive diagnosis of MM. The patient was eventually discharged to a nursing home for hospice care. This case sheds light on the importance of preventative care in routine outpatient setting, which can often screen, identify, and detect malignancies at earlier stages. It also signifies the importance of an interdisciplinary approach and precise knowledge in differentiating and diagnosing such malignancies. In our patient's case, his extensive bone disease precluded his ability to be weight bearing which is an uncommon finding only seen in extensive metastatic bone disease. A definitive diagnosis is warranted to guide appropriate management.

The study focuses on the development of novelAloe verabased polymeric composite films and antimicrobial suture coatings. Polyvinyl alcohol (PVA), a synthetic biocompatible and biodegradable polymer, was combined withAloe vera, a natural herb used for soothing burning effects and cosmetic purposes. The properties of these two materials were combined together to get additional benefits such as wound healing and prevention of surgical site infections. PVA andAloe verawere mixed in a fixed quantity to produce polymer based films. The films were screened for antibacterial and antifungal activity against bacterial (E. coli,P. aeruginosa) and fungal strains (Aspergillus flavusandAspergillus tubingensis) screened.Aloe verabased PVA films showed antimicrobial activity against all the strains; the lowestAloe veraconcentration (5%) showed the highest activity against all the strains.In vitrodegradation and release profile of these films was also evaluated. The coating for sutures was prepared,in vitroantibacterial tests of these coated sutures were carried out, and later onin vivostudies of these coated sutures were also performed. The results showed that sutures coated withAloe vera/PVA coating solution have antibacterial effects and thus have the potential to be used in the prevention of surgical site infections andAloe vera/PVA based films have the potential to be used for wound healing purposes.

INTRODUCTION Injuries cover about 11% of World's Disease Burden depicting fractures to be the leading severe consequence of trauma. Fractures occur due to force impact or osteoporosis. Fracture healing is a complicated process. Fracture fixation techniques focus on imparting reduction to fractured fragments and induce healing. When considering possible fixation methods, the aspect of micro-movement is an important one, as this induces callus formation which tends to be a crucial step for fracture healing. Internal fixation of long bone fractures using metallic plates has been carried out since decades and recently advancements have been in synthesizing biodegradable plates as well. The purpose of this research was to fabricate an Auxetic Polymeric Bone Plate that can be used as an internal fixator for long bone fracture; this bone plate renders micro-movement due to its counter intuitive behavior, has the potential to reduce the effect of stress shielding and allow the same range of motion as that of natural bone. METHODS Polyurethane was chosen as a material for the fabrication of the Auxetic device because of its biocompatibility and non-toxic effects. The plate was then tested for mechanical properties such as Tensile and Compression testing to determine the strength. RESULTS AND DISCUSSION The tensile testing of the Auxetic polyurethane specimens showed that the mean of the Poisson's ratio of the samples lies between -0.68 and -0.87 at different uni-axial tensile load values. The Auxetic structure of our device has the potential to allow for efficient fixation because its negative Poisson's ratio offers micro-movement, thereby causing fixation with relative stability rather than absolute stability. The Auxetic bone plate can be superior to contemporary plate fixation systems, as it demands meaningfully small contact points. The suitable mechanical properties might lessen stress shielding effects that are normally caused by rigid bone plates. The Auxetic nature of the bone will help align and sustain the bone fragments with small fracture gaps in order to impart appropriate assembly to accomplish bone healing.

Fracture fixation techniques, fracture management, and orthopedic trauma care have evolved, and various advancements have been made in the last 50 years. Minimally invasive biological osteosynthetic devices have the potential of transforming the prospects of orthopedic treatment. Internal fixation techniques offer tremendous advantages in the management of bone fractures. The main objective of this study was to fabricate a novel auxetic polymeric bone stent with potential applications in internal fixation procedures. A new “connected stars” geometry has been used for the fabrication of this device. After fabrication, the mechanical characterization of the auxetic bone stent was also carried out to study its properties and deformation behavior. The research work undertaken also assesses the potential for auxetic behavior of these tubular structures.

Background Cardiovascular heart disease is one of the leading health issues in the present era and requires considerable health care resources to prevent it. The present study was focused on the development of a new coronary stent based on novel auxetic geometry which enables the stent to exhibit a negative Poisson's ratio. Commercially available coronary stents have isotropic properties, whereas the vascular system of the body shows anisotropic characteristics. This results in a mismatch between anisotropic–isotropic properties of the stent and arterial wall, and this in turn is not favorable for mechanical adhesion of the commercially available coronary stents with the arterial wall. It is believed that an auxetic coronary stent with inherent anisotropic mechanical properties and negative Poisson's ratio will have good mechanical adhesion with the arterial wall. Methods The auxetic design was obtained via laser cutting, and surface treatment was performed with acid pickling and electropolishing, followed by an annealing process. In vitro mechanical analysis was performed to analyze the mechanical performance of the auxetic coronary stent. Scanning electronic microscopy (SEM) was used to determine the effects of fabrication processes on the topography of the auxetic stent. Results and Conclusions The elastic recoil (3.3%) of the in vitro mechanical analysis showed that the auxetic stent design effectively maintained the luminal patency of the coronary artery. Also, the auxetic coronary stent showed no foreshortening, therefore it avoids the problem of stent migration, by expanding in both the radial and longitudinal directions. By virtue of its synclastic behavior, the auxetic stent bulges outward when it is radially expanded through an inflated balloon.

A novel mononuclear copper complex [Cu(NH2mpdH)(NH2mpd)2Cl] (1) is synthesized from 2-amino-2-methyl-1,3-propandiol (ampdH4). The crystal structure of (1) is determined using X-ray diffraction studies. The copper complex crystallizes in the triclinic space group P-1(2) with a = 6.10.48(4) A, b = 10.0915(7) A, c = 10.9249(9) A, α = 95.925(6)°, β = 101.830(6)°, γ = 90.637(5)°, V = 649.53(95) A3 and Z = 2. The central copper(II) atom in (1) is coordinated by three oxygen and two nitrogen atoms possessing a five-coordinate distorted square pyramidal geometry arranged in a one dimensional polymeric chain. The ground state geometry of the mononuclear copper complex is optimized using the DFT/B3LYP/6-31G** (LANL2DZ) level of theory. Intra-molecular charge transfer is investigated based on the frontier molecular orbitals. The distribution pattern of the highest occupied molecular orbital and the lowest unoccupied molecular orbital is studied. Absorption spectra are computed using The time dependent density functional theory (TDDFT). The absorption wavelengths are calculated using different functionals, i.e., BHandHLYP, CAM-B3LYP, and LC-BLYP.

Wounds are of a variety of types and each category has its own distinctive healing requirements. This realization has spurred the development of a myriad of wound dressings, each with specific characteristics. It is unrealistic to expect a singular dressing to embrace all characteristics that would fulfill generic needs for wound healing. However, each dressing may approach the ideal requirements by deviating from the ‘one size fits all approach’, if it conforms strictly to the specifications of the wound and the patient. Indeed, a functional wound dressing should achieve healing of the wound with minimal time and cost expenditures. This article offers an insight into several different types of polymeric materials clinically used in wound dressings and the events taking place at cellular level, which aid the process of healing, while the biomaterial dressing interacts with the body tissue. Hence, the significance of using synthetic polymer films, foam dressings, hydrocolloids, alginate dressings, and hydrogels has been reviewed, and the properties of these materials that conform to wound-healing requirements have been explored. A special section on bioactive dressings and bioengineered skin substitutes that play an active part in healing process has been re-examined in this work.

Antibiotic loaded calcium deficient apatite (CDA) granules were prepared by wet chemical synthesis followed by microwave irradiation. Microporous CDA granules were loaded with three broad spectrum antibiotics (Amoxicillin, Gentamicin and Chloramphenicol). The aim of this study was to evaluate the in-vitro performance of locally released antibiotics which has a potential to treat infected osseous defects. In-vitro studies of the synthesized material elucidated high drug loading capacity and a drug release profile spanning a period of more than 24 h. The respective antibiotic functional groups were analyzed by Fourier Transform Infrared Spectroscopy (FT-IR). X-ray Diffraction (XRD) was used to study the phase purity of synthesized CDA. Drug release profiles were determined by using UV–vis Spectroscopy. Scanning Electron Microscopy (SEM) was used to investigate granule sizes and porosity. Particle size (2–20 mm) with an average pore diameter of 2.9 mm (70.5 mm) was achieved without heat-treatment and use of any porogens. Thermal stability was determined using simultaneous Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). The drug release profile showed initial burst release followed by sustained release periodically. & 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

The spectroscopic and molecular structure of 2-{(E)-[(6-methylpyridin-2-yl)imino]methyl}phenol (MPMP) has been characterized by FT-IR, UV–Vis and X-ray diffraction. The ground state geometry of MPMP has been optimized by using density functional theory at DFT/B3LYP/6-31G** and DFT/B3LYP/6-31 + G* level of theories. The DFT/B3LYP/6-31 + G* level of theory is good to reproduce the geometrical parameters. We shed light on the frontier molecular orbitals; highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) which play important role in charge transfer properties. The absorption spectrum was calculated by using time dependent density functional theory at TD-B3LYP/6-31 + G* level of theory. The absorption wavelengths were computed in different solvents by using polarizable continuum model (PCM). The solvent polarity effect was studied on the absorption wavelengths. The structure–property relationship has been discussed intensively.

For achieving additional benefits and improving the material characteristics two or more materials are often combined together in the form of composites. Composites are important because of their light weight, high strength and flexibility of design. Composite materials provide various advantages based on their particulate or fibrous nature and on the basis of individual qualities of the constituting elements of the composites. Besides the multiplied benefits achieved with the composite materials, they being composed of two different materials exhibit greater challenges and biocompatibility threats which need to be addressed while developing a composite material. A structural composite of bioabsorbable nature is developed using a polymeric material and metal particles. The composite material so developed would provide altered strength and flexibility, better than the individual constituting materials for use in various biomedical devices and would eventually degrade on subject to exposure to the physiological environment. The two different varieties of the composite have been developed using metal particles and metal salt and they have been tested for their tensile, degradation and drug release properties, which have been found satisfactory for use of the composite in various biomedical devices and drug release applications.

We present the case of a 74-year-old woman with metastatic lobular carcinoma with an occult breast primary presenting as a suspected ampullary tumor due to its ampullary metastasis. The patient's clinical presentation is of interest in two aspects. First, lobular carcinoma of the breast metastatic to the ampulla is extremely rare. Second, in the absence of a detectable primary lesion, prior history of malignancy, or distinguishing clinical, radiological, and endoscopic features, histopathological assessments are pivotal for arriving at the appropriate diagnosis and for optimizing treatment.

One of the important mechanical properties of materials is Poisson’s ratio, which is positive for most of the materials. However, certain materials exhibit “auxetic” properties; that is, they have a negative Poisson’s ratio. Thus auxetic and non-auxetic materials exhibit different deformation mechanisms. A specific microscopic structure in the auxetic materials is important for maintaining a negative Poisson’s ratio. Based on their distinct nature auxetic materials execute certain unique properties in contrast to other materials, which are reviewed in this paper. Thus auxetic materials have important applications in the biomedical field which are also a part of this review article. Many auxetic materials have been discovered, fabricated, and synthesized which differ on the basis of structure, scale and deformation mechanism. The different types of auxetic materials such as auxetic cellular solids, microscopic auxetic polymers, molecular auxetic materials, and auxetic composites have been reviewed comprehensively in this paper. Modeling of auxetic structures is of considerable importance and needs appropriate stress strain configurations; thus different aspects of auxetic modeling have also been reviewed. Packing parameters and relative densities are of prime importance in this regard. This review would thus help the researchers in determining and deciding the various aspects of auxetic nature for their products.

BACKGROUND: According to the Centers for Disease Control and Prevention, Clostridium difficile causes 337,000 infections and 14,000 deaths annually. Infection Preventionists can proactively reduce hospital-onset C. difficile infections (HO-CDI) by utilizing a multidisciplinary performance improvement (PI) approach. The formulation of policies along with the support of management, medical staff, nursing and ancillary staff can result in a statistically significant reduction of patient harm. METHODS: Infection Peventionists at a 716 bed safety-net hospital observed a statistically significant increase in HO-CDI between January and July 2014 utilizing statistical process control charts (SPC). C. difficile infections (CDI) were identified using the National Hospital and Safety Network 2014-2015 definition; patients identified as C. difficile toxin positive on or after calendar day four of admissionwere considered to be hospital-onset. Despite efforts, in June 2015, SPC revealed another statistically significant deviation and an outbreak investigation exposed potential evidence of nosocomial spread in a medical-surgical unit. A hospital-wide policy titled “Enhanced Contact Precautions” for CDIwas implemented in July 2015. By clarifying Enhanced Contact Precautions for CDI, patient care providerswere prompted towashhandswith soap and water and clean patient rooms with a bleach product. RESULTS: The increase in HO-CDI spurred the formation of a multidisciplinary PI approach that resulted in a 41% decrease in the HOCDI rate from August 2014 to April 2015. In June of 2015 another CDI outbreakwas identified and the infection rate increased to 13.50/ 10,000 patient days (+3 sigma). Subsequent PI efforts resulted in a decrease in the HO-CDI rate to an average of 3.62/10,000 patient days from July to October 2015. CONCLUSIONS: Multidisciplinary PI, including comprehensive staff education, enhanced terminal cleaning, enhanced contact isolation, changes in the electronic medical record to augment continuity of care and the initiation of a hand hygiene subcommittee resulted in a significant reduction in HO-CDI rates.