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1.
Cureus ; 15(6): e40965, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37503501

ABSTRACT

Background Renal calculi remain a major economic and health burden worldwide and are considered a systemic disorder associated with multiple other diseases. Several studies have observed that patients with idiopathic calcium renal stones show a reduction in bone mass. This study aimed to evaluate bone mass reduction on a non-contrast CT scan study in a group of idiopathic calcium-containing renal calculus disease patients in comparison with subjects without renal calculus disease. Methodology This non-interventional, cross-sectional study included a total of 300 patients with 150 cases (with renal calculi) and 150 controls (without renal calculi). Patients were divided according to age groups of 18-40, 40-60, and more than 60 years. The renal calculus size and the mean iliac bone thickness were calculated, and Spearman's correlation test was used to determine the correlation between them. Results The mean iliac bone thickness was significantly lower in the cases (3.29 mm) compared to the controls (9.73 mm with a standard deviation of 1.341 mm). There was a statistically significant negative correlation between the size of the renal calculus and the mean iliac bone thickness. Conclusions Renal calculus disease associated with hypercalciuria caused by increased bone resorption is reflected by the decreased iliac bone thickness on CT scans. Our study used the iliac bone (cancellous bone) in predicting bone mass reduction which shows changes early in the course of the disease compared to the neck of the femur and lumbar vertebrae (compact bones). It helps in predicting osteoporosis early and prevents the progression of the disease through early and appropriate clinical and urological intervention.

2.
Disabil Rehabil Assist Technol ; 18(1): 97-108, 2023 01.
Article in English | MEDLINE | ID: mdl-33337923

ABSTRACT

PURPOSE: Existing wheelchair (WC) designs lack independent toilet accessibility, transferability and indoor manoeuvrability combined in a WC. In this regard, a new WC model is proposed to simultaneously accommodate these distinct and essential features. In this open-source hardware project, the design, analysis and fabrication of a new active commode WC for indoor applications are performed. MATERIALS AND METHOD: A field survey is conducted to identify the requirements of users so as to choose specific features and design constraints for the WC. In this multipurpose self-propelled model, a temporarily detachable circular section is fitted in the seat position to access the water closet bowl. This hinged portion can be released by gravity before reaching above the closet basin. After the toilet usage, the circular lid can be brought back to the initial seating using a lever mechanism and a spring-loaded lock restrains its downward movement. Thereafter, it can be used as an ordinary WC for indoor applications. Moreover, a small wheel with 22 in diameter and removable hand-rests ensured the transferability between utilities. A CAD model is prepared and numerical simulation is performed to verify the structural stability of the design. RESULTS: The optimized model is fabricated using standard manufacturing practices and is delivered to different persons with disabilities to collect user feedback. A systematic skill test is conducted to validate the compliance of the prototype with the user requirements including transferability and independent restroom access. CONCLUSION: The opinions from most of the users are positive which categorically indicated that the proposed design addresses the multipurpose mobility requirements at indoors.Implications for rehabilitationThe expected outcomes and implications of the current commode WC project with regard to rehabilitation purpose are enlisted below:In the present scenario, a WC user is heavily dependent on external assistance to access private spaces in general and toilets in particular. The introduced model is capable to address this shortcoming by enabling the user to access the toilet utility directly by self propelling.Indeed, for a person with locomotor disability, a WC is the natural extension of his physical body. Thereby, this multipurpose commode WC design offers much Independence and greater flexibility to the indoor movements.The proposed design instils confidence to a WC user to access and transfer between facilities by means of self effort. Consequently it is expected to improve the quality of one's personal life significantly.Importantly, this is an open-source project, those who are interested in rehabilitation motives can modify the present design to suit their local requirements especially in resource-limited settings.


Subject(s)
Bathroom Equipment , Disabled Persons , Self-Help Devices , Wheelchairs , Humans , Disabled Persons/rehabilitation , Toilet Facilities , Equipment Design
3.
Nat Chem ; 13(12): 1200-1206, 2021 12.
Article in English | MEDLINE | ID: mdl-34635814

ABSTRACT

The micron-scale movement of biomolecules along supramolecular pathways, mastered by nature, is a remarkable system requiring strong yet reversible interactions between components under the action of a suitable stimulus. Responsive microscopic systems using a variety of stimuli have demonstrated impressive relative molecular motion. However, locating the position of a movable object that travels along self-assembled fibres under an irresistible force has yet to be achieved. Here, we describe a purely supramolecular system where a molecular 'traveller' moves along a 'path' over several microns when irradiated with visible light. Real-time imaging of the motion in the solvated state using total internal reflection fluorescence microscopy shows that anionic porphyrin molecules move along the fibres of a bis-imidazolium gel upon irradiation. Slight solvent changes mean movement and restructuring of the fibres giving microtoroids, indicating control of motion by fibre mechanics with solvent composition. The insight provided here may lead to the development of artificial travellers that can perform catalytic and other functions.

4.
Contemp Clin Dent ; 12(2): 169-173, 2021.
Article in English | MEDLINE | ID: mdl-34220158

ABSTRACT

The purpose of this case report is to describe and discuss a combined surgical and orthodontic technique for the management of transverse maxillary deficiency and mandibular prognathism in the treatment of skeletal Class III malocclusion in a mature patient. Skeletal Class III malocclusion can present with maxillary deficiency or retrognathism, mandibular excess or prognathism, or a combination. The maxillary arch is narrow and often requires expansion. A 25-year-old patient presented with a constricted maxilla, a skeletal Class III malocclusion with a large mandible, Angle's Class III malocclusion, retroclined lower incisors, proclined upper incisors, crowding of maxillary and mandibular teeth, and bilateral posterior crossbite. The case report shows that an adult patient with Class III malocclusion (constricted maxilla and large mandible) can be treated with rapid maxillary expansion accompanied by bilateral maxillary osteotomies, followed by a reduction bilateral sagittal split osteotomy (BSSO). As the patient was 25 years old with a bilateral crossbite, a surgically assisted rapid maxillary expansion procedure was performed. As the diastema space was available at the end of expansion, it proved to be beneficial for the presurgical decompensation of Class III, thus creating a negative overjet, followed by which a BSSO setback was done.

5.
Biomicrofluidics ; 14(3): 034111, 2020 May.
Article in English | MEDLINE | ID: mdl-32549924

ABSTRACT

Real-time object identification and classification are essential in many microfluidic applications especially in the droplet microfluidics. This paper discusses the application of convolutional neural networks to detect the merged microdroplet in the flow field and classify them in an on-the-go manner based on the extent of mixing. The droplets are generated in PMMA microfluidic devices employing flow-focusing and cross-flow configurations. The visualization of binary coalescence of droplets is performed by a CCD camera attached to a microscope, and the sequence of images is recorded. Different real-time object localization and classification networks such as You Only Look Once and Singleshot Multibox Detector are deployed for droplet detection and characterization. A custom dataset to train these deep neural networks to detect and classify is created from the captured images and labeled manually. The merged droplets are segregated based on the degree of mixing into three categories: low mixing, intermediate mixing, and high mixing. The trained model is tested against images taken at different ambient conditions, droplet shapes, droplet sizes, and binary-fluid combinations, which indeed exhibited high accuracy and precision in predictions. In addition, it is demonstrated that these schemes are efficient in localization of coalesced binary droplets from the recorded video or image and classify them based on grade of mixing irrespective of experimental conditions in real time.

6.
Phys Chem Chem Phys ; 19(41): 28225-28231, 2017 Oct 25.
Article in English | MEDLINE | ID: mdl-29027550

ABSTRACT

Ultrafast intersystem crossing of carbonylpyrenes in chloroform was investigated by femtosecond pump-probe spectroscopy. When compared to the dominant fluorescence decay pathway in pyrene, carbonyl functionalized pyrenes display near-unity triplet formation upon photoexcitation. The excited singlet state (Sp) undergoes rapid intersystem crossing (kISC) concomitantly with internal conversion (kIC) to lower excited singlet states (Sn) within a timescale of 5-11 ps (1/τ2 = kIC + kISC). Furthermore, intersystem crossing from lower excited singlet states (Sn) proceeds through coupling with receiver triplet states, eventually leading to high triplet quantum yields (ΦT = 97%; tetraacetylpyrene). Followed by internal conversion in the triplet manifolds, phosphorescence decay on a microsecond timescale is observed from the emitter triplet state.

7.
Chem Sci ; 8(3): 1776-1782, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28694952

ABSTRACT

We describe the design, bottom-up synthesis and X-ray single crystal structure of systematically twisted aromatics 1c and 2d for efficient intersystem crossing. Steric congestion at the cove region creates a nonplanar geometry that induces a significant yield of triplet excited states in the electron-poor core-twisted aromatics 1c and 2d. A systematic increase in the number of twisted regions in 1c and 2d results in a concomitant enhancement in the rate and yield of intersystem crossing, monitored using femtosecond and nanosecond transient absorption spectroscopy. Time-resolved absorption spectroscopic measurements display enhanced triplet quantum yields (Φ T = 10 ± 1% for 1c and Φ T = 30 ± 2% for 2d) in the twisted aromatics when compared to a negligible Φ T (<1%) in the planar analog 3c. Twist-induced spin-orbit coupling via activated out-of-plane C-H/C[double bond, length as m-dash]C vibrations can facilitate the formation of triplet excited states in twisted aromatics 1c and 2d, in contrast to the negligible intersystem crossing in the planar analog 3c. The ease of synthesis, high solubility, access to triplet excited states and strong electron affinity make such imide functionalized core-twisted aromatics desirable materials for organic electronics such as solar cells.

8.
Clin Exp Obstet Gynecol ; 44(1): 110-112, 2017.
Article in English | MEDLINE | ID: mdl-29714877

ABSTRACT

Hypertension during pregnancy has been extensively studied due to significant maternal morbidity, mortality, and perinatal mortality that may result. The outcome in hypertensive disorders in pregnancy vary significantly across populations and between institutions serving the same populace. OBJECTIVE: In the present study, the authors sought to determine the outcome for mother and fetus with pregnancy induced hypertension (PIH) in a rural community at a tertiary care center at Thrissur Medical College, Kerala, India. MATERIALS AND METHODS: The authors included all singleton pregnancies with hypertensive disease that had deliveries in our institution in a six-month period excluding the ones with pre-existing hypertension and other comorbidities. RESULTS: 46.5% ofthe patients required a cesarean section, 37.2% had pre-term labor, 52.4% had low birth weight, and 9.4% unfortunately were stillborn. DISCUSSION: These results emphasize the need for screening and close follow-up of hypertension in pregnancy for safeguarding fetal and maternal wellbeing. Even after practicing the current standard of care, the higher rate of complications associated with PIH is unacceptable. The authors feel that unique management protocols should be implemented for different patient populations, based on ethnicity, lifestyle, and availability of medical resources.


Subject(s)
Hypertension, Pregnancy-Induced/epidemiology , Adult , Cesarean Section/statistics & numerical data , Female , Humans , India/epidemiology , Infant, Low Birth Weight , Infant, Newborn , Obstetric Labor, Premature/epidemiology , Pregnancy , Stillbirth/epidemiology , Young Adult
9.
J Phys Chem Lett ; 7(22): 4751-4756, 2016 Nov 17.
Article in English | MEDLINE | ID: mdl-27934208

ABSTRACT

Twisted donor-on-donor and acceptor-on-acceptor bicontinuous assembly in all-carbon pyren-1-ylaceanthrylene (PA) dyad extends the survival time of the photoinduced radical ion-pair intermediates. Aceanthrylene, a functional analog of C70, acts as a versatile electron acceptor owing to its high electron affinity and visible light absorption. Antithetical trajectories of the excitons in the nonparallel π-ways led to persistent radical ion-pair intermediates in aggregated (τcrA ∼ 1.28 ns) vs monomeric (τcrM ≤ 110 fs) PA dyad as observed using femtosecond transient absorption spectroscopy. Marcus theory of charge transfer rates predicts an ambipolar transport characteristic in crystalline PA, thereby endorsing PA as an all-carbon DA hybrid for nonfullerene photovoltaic applications.

10.
Int J Appl Basic Med Res ; 6(1): 38-44, 2016.
Article in English | MEDLINE | ID: mdl-26958521

ABSTRACT

AIMS AND OBJECTIVES: Cerebral ischemic stroke is life-threatening and debilitating neurological disease, it is the third leading cause of death in the world. Studies have shown that there is a close relationship between carotid artery stenosis and ischemic cerebral vascular disease. This study is done to assess the carotid arteries with the help of color Doppler sonography and to correlate cerebrovascular accidents. MATERIALS AND METHODS: The prospective study was carried out on 50 patients using purposive sampling technique. Risk factors such as hypertension, diabetes mellitus, smoking, and family history were documented. The data gathered from color Doppler examination consisted of peak systolic velocity of common carotid artery (CCA) and internal carotid artery (ICA), velocity ratios between CCA and ICA and plaque characteristics as seen on real-time image. STATISTICAL ANALYSIS USED: The collected data were analyzed and presented in the form of tables, figures, graphs, and diagrams wherever necessary. As this study deals with the only frequency distribution of various factors, so no tests of significance were applied. RESULTS: The highest incidence of stroke was found in the male population in the age group of 60-69 years. Various risk factors included hypertension, diabetes mellitus, smoking, and family history. Of 50 patients, 12 patients showed significant stenosis (>60%). Atherosclerotic plaques were seen in 39 patients (78%). CONCLUSION: Color Doppler examination is an economic, safe, reproducible, and less time-consuming method of demonstrating the cause of cerebrovascular insufficiency in extracranial carotid artery system and will guide in instituting treatment modalities.

11.
J Am Chem Soc ; 137(50): 15604-7, 2015 Dec 23.
Article in English | MEDLINE | ID: mdl-26440563

ABSTRACT

We report a nonparallel stacked arrangement of donor­acceptor (D­A) pairs for prolonging the lifetime of photoinduced charge-separated states. Hydrogen­hydrogen steric repulsion in naphthalimide-naphthalene (NIN) dyad destabilizes the planar geometry between the constituent units in solution/ground state. Sterically imposed nonplanar geometry of the dyad allows the access of nonparallel arrangement of the donor and acceptor stacks having triclinic space group in the crystalline state. Antiparallel trajectory of excitons in nonparallel D­A stacks can result in lower probability of geminate charge recombination, upon photoexcitation, thereby resulting in a long-lived charge-separated state. Upon photoexcitation of the NIN dyad, electron transfer from naphthalene to the singlet excited state of naphthalimide moiety results in radical ion pair intermediates that survive >10,000-fold longer in the aggregated state (τcra > 1.2 ns) as compared to that of monomeric dyad (τcrm < 110 fs), monitored using femtosecond transient absorption spectroscopy.

13.
Gulf J Oncolog ; 1(16): 84-8, 2014 Jul.
Article in English | MEDLINE | ID: mdl-25316397

ABSTRACT

The tumors of the anterior cranial cavity can either be malignant or benign. They usually arise in the nasal or Para nasal sinuses. Treatment of these tumors includes major craniofacial resection and reconstruction to prevent cerebrospinal fluid leak and meningitis. In this study we are presenting a technique which is simple and cost-effective. We are reporting a series of nine cases in which this technique was tried out and we found that it can be used for dural repair and anterior cranial fossa reconstruction with no major complications.

14.
J Pharm Bioallied Sci ; 6(Suppl 1): S150-5, 2014 Jul.
Article in English | MEDLINE | ID: mdl-25210359

ABSTRACT

BACKGROUND AND OBJECTIVES: The purpose of this study is to evaluate the frictional resistance generated by conventional stainless steel, radiance ceramic bracket, self-ligating and composite brackets using a 0.019 × 0.025 stainless steel straight length wires in a 022 slot and to select brackets based on their frictional characteristic. METHODOLOGY: In order to conduct this study, four different types of bracket system were selected of the mclaughlin-bennet-trevesi (MBT) discipline. They are Group 1 - stainless steel, Group 2 - composite bracket Group 3 - (American Orthodontics) radiance ceramic bracket Group 4 - self-ligating bracket (SLB) (Empower). In this study, five maxillary brackets of an arch of each type were used. All brackets are 0.022 × 0.028 in preadjusted edgewise appliance which simulates the dental arch. Five brackets were bonded to a stainless steel bar of dimension 150 mm × 25 mm × 3 mm. The bracket-arch wire units were submitted to mechanical test with an Instron universal testing machine 3365. A testing apparatus or holding jig was designed to hold the bracket during the mechanical test. Each sample was pulled at a speed of 6 mm for 1 min. Descriptive statistical information including mean and standard deviation of maximum friction force was calculated for each bracket wire combination. INTERPRETATION AND CONCLUSION: The SLB has the least friction among the four groups. The ceramic bracket showed the highest friction followed by stainless steel bracket, composite bracket, and SLB.

15.
Indian J Dent Res ; 24(6): 701-7, 2013.
Article in English | MEDLINE | ID: mdl-24552930

ABSTRACT

BACKGROUND: When ceramic brackets were introduced as an esthetic alternative to the stainless steel brackets, it was a step ahead in the use of esthetic appliances for orthodontic treatment. Although ceramic brackets had overcome the drawbacks of the initial polycarbonate brackets such as staining and bracket slot distortion, they posed an altogether different problem. This was on account of the physical properties of the ceramic material, namely brittleness. PURPOSE OF THE STUDY: The purpose of this study is to investigate the physical properties of three different varieties of esthetic brackets, i.e., "MXI" ceramic bracket, "Spirit MB" bracket (Ormco), a composite bracket with metal slot reinforcement and the third one fiber bracket, with silicious copolymer, Natura (Leone Co.). AIMS AND OBJECTIVE OF THE STUDY: The objective of this study is to compare the torsional resistance of the brackets and resistance of brackets to second order archwire activations. CONCLUSION: The strength of the selected brackets was more than sufficient to withstand orthodontic load without any fracture or deformation.


Subject(s)
Esthetics, Dental , Orthodontic Brackets , Orthodontic Wires , Equipment Design , Humans , In Vitro Techniques
16.
Phys Chem Chem Phys ; 14(44): 15282-5, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-23051919

ABSTRACT

With an increase in temperature, an unprecedented restoration of symmetry in the symmetry breaking excited state charge transfer is observed in a geminal pair of near-orthogonally connected perylenimide dimers. Such restoration of symmetry could be attributed to the interchromophoric planarization and/or loss of solvation asymmetry at elevated temperature resulting in enhanced fluorescence quantum yield.


Subject(s)
Imides/chemistry , Perylene/analogs & derivatives , Temperature , Dimerization , Imides/chemical synthesis , Perylene/chemical synthesis , Perylene/chemistry
17.
Case Rep Dent ; 2012: 735925, 2012.
Article in English | MEDLINE | ID: mdl-23346424

ABSTRACT

Fusion or synodontia is a union of two or more than two developing teeth. Commonly fusion occurs between teeth of the same dentition, mixed dentition, or between normal and supernumerary teeth. Fused primary teeth present with several clinical problems like caries, periodontal problem, arch asymmetry, delayed eruption, ectopic eruption of succedaneous teeth, aesthetic, and other complications. This paper presents a rare and unusual case of triple teeth in mandibular primary dentition.

18.
Endocrinology ; 148(2): 575-84, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17110428

ABSTRACT

Osteopontin (OPN), a phosphorylated glycoprotein that binds to an integrin-binding motif, has been shown to regulate nitric oxide (NO) production via inhibition of induced NO synthase (iNOS) synthesis. In the transplanted islets, iNOS and toxic amounts of NO are produced as a result of islets infiltration with inflammatory cells and production of proinflammatory cytokines. Here, we demonstrate that addition of OPN before IL-1beta in freshly isolated rat islets improved their glucose stimulated insulin secretion dose-dependently and inhibited IL-1beta-induced NO production in an arginine-glycine-aspartate-dependent manner. Transient transfection of OPN gene in RINm5F beta-cells fully prevented the toxic effect of IL-1beta at concentrations that reduced the viability by 50% over 3 d. OPN prevention of IL-1beta-induced toxicity was accompanied by inhibited transcription of iNOS by 80%, resulting in 50% decreased formation of the toxic NO. In OPN-transfected cells, the IL-1beta-induced nuclear factor-kappaB activity was significantly reduced. Islets exposed to IL-1beta revealed a naturally occurring early up-regulated OPN transcription. OPN promoter activity was increased in the presence of IL-1beta, IL-1beta-induced NO, and an inducer of NO synthesis. These data suggest the presence of a cross talk between the IL-1beta and OPN pathways and a unique trans-regulatory mechanism in which IL-1beta-induced NO synthesis feedback regulates itself through up-regulation of OPN gene transcription. Our data also suggest that influencing OPN expression represents an approach for affecting cytokine-induced signal transduction to prevent or reduce activation of the cascade of downstream devastating effects after islet transplantation.


Subject(s)
Cytotoxins/pharmacology , Feedback, Physiological , Insulin-Secreting Cells/drug effects , Interleukin-1beta/pharmacology , Islets of Langerhans/drug effects , Nitric Oxide/metabolism , Osteopontin/pharmacology , Animals , Cell Line, Tumor , Cell Survival/drug effects , Cells, Cultured , Cytotoxins/antagonists & inhibitors , Gene Expression/drug effects , Insulin/metabolism , Insulin Secretion , Insulin-Secreting Cells/metabolism , Insulin-Secreting Cells/physiology , Interleukin-1beta/antagonists & inhibitors , Interleukin-1beta/metabolism , Islets of Langerhans/metabolism , Male , Mice , NF-kappa B/metabolism , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Nitric Oxide Synthase Type II/antagonists & inhibitors , Nitric Oxide Synthase Type II/biosynthesis , Nitric Oxide Synthase Type II/genetics , Oligopeptides/physiology , Osteopontin/genetics , Osteopontin/metabolism , Promoter Regions, Genetic/drug effects , RNA, Messenger/metabolism , Rats , Rats, Wistar , Signal Transduction/drug effects , Transcription, Genetic , Transfection
19.
BMC Biotechnol ; 4: 23, 2004 Oct 15.
Article in English | MEDLINE | ID: mdl-15485583

ABSTRACT

BACKGROUND: Several cell lines and primary cultures benefit from the use of positively charged extracellular matrix proteins or polymers that enhance their ability to attach to culture plates. Polyethyleneimine is a positively charged polymer that has gained recent attention as a transfection reagent. A less known use of this cationic polymer as an attachment factor was explored with several cell lines. RESULTS: Polyethyleneimine compared favorably to traditional attachment factors such as collagen and polylysine. PC-12 and HEK-293 cells plated on dishes coated with polyethyleneimine showed a homogeneous distribution of cells in the plate, demonstrating strong cell adhesion that survived washing procedures. The polymer could also be used to enhance the adherence and allow axonal outgrowth from zebrafish retinal explants. The effects of this coating agent on the transfection of loosely attaching cell lines were studied. Pre-coating with polyethyleneimine had the effect of enhancing the transfection yield in procedures using lipofection reagents. CONCLUSION: Polyethyleneimine is an effective attachment factor for weakly anchoring cell lines and primary cells. Its use in lipofection protocols makes the procedures more reliable and increases the yield of expressed products with commonly used cell lines such as PC-12 and HEK-293 cells.


Subject(s)
Cell Culture Techniques , Liposomes/metabolism , Polyethyleneimine/metabolism , Polymers/metabolism , Animals , Biocompatible Materials , Cell Adhesion , Cell Line , Extracellular Matrix Proteins , Humans , Kidney/chemistry , Kidney/cytology , Kidney/embryology , Kidney/metabolism , PC12 Cells/cytology , PC12 Cells/metabolism , Rats , Surface Properties , Transfection/methods , Transfection/standards
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