Paper Patches Research Articles

Development of a disposable paper-based thin film solid-phase microextraction sampling kit to quantify ketone body.

Diabetes ketoacidosis (DKA) is a life-threatening complication and requires immediate medical attention in the case of diabetes subjects, especially in the case of type 1 diabetes mellitus. In the condition of DKA, the body produces an excess amount of ketone bodies after unregulated fat degradation, causing blood to become acidic and hampering the regular metabolic activities of the body. The current diagnostic technique for DKA condition is based on monitoring ketone bodies, especially β-hydroxybutyric acid, from human urine and blood samples. The detection of serum ketone bodies in pathology is sometimes limited due to false positive results and the lack of standardization for precise quantification of analytes. In this study, a paper-based patch operating on the thin film solid-phase microextraction (TF-SPME) principle was developed and it was coupled with gas chromatography-mass spectrometry for simple quantification of β-hydroxybutyric acid (BHB) ketone body from a phosphate-buffered saline matrix. To fabricate the paper-based TF-SPME patches, a regular A4 sheet paper sheet was utilized as the substrate and uniform coating by multiwalled carbon nanotubes (MWCNT), polydimethylsiloxane (PDMS) and divinyl benzene (DVB) compounds was performed with an automatic film applicator. The 70 μm paper-based coated sheet was trimmed into 4 cm × 1 cm dimension pieces to obtain multiple patches from a single sheet. Extraction of the BHB ketone body into the closed vials was performed by exploiting the individual DVB/PDMS and DVB/CNT/PDMS paper patches followed by desorption with acetonitrile before quantification by gas chromatography-mass spectrometry analysis. Our study showed that the BHB extraction efficiency of DVB/PDMS-coated patches was higher than that of DVB/CNT/PDMS. The outcome showed a good linearity (R 2 = 0.99) within the 500-20 000 ng mL-1 concentration range of BHB by paper-based DVB/PDMS patches. This study demonstrated the feasibility of utilizing simple, cost-effective paper-based disposable TF-SPME patches as a sampling kit for future screening of diabetes ketoacidosis without the need for prolonged traditional sample preparation in pathology.

Human Acellular Dermal Allograft Patch on Traumatic Tympanic Membrane Perforation.

This study aimed to investigate the outcome of using the human acellular dermal allograft patch compared with the conven- tional paper patch in traumatic tympanic membrane perforation. This was a retrospective study including 41 patients (42 ears) treated with 22 human acellular dermal allografts and 20 paper patches for acute traumatic tympanic membrane perforation from April 2013 to June 2020. The procedure was performed by applying human acellular dermal allograft or paper patches after trimming of perforation margins under local anesthesia. Patient's age, sex, cause, duration, side, location, size of perforation, and the result of healing was analyzed. The audiologic or computed tomography data were also investigated when available. There was no significant difference in sex, age, affected side ratio, size and duration of perforation, recovery confirmation time, and audiogram results between the two groups. There was no significant difference in the size or duration of perforation between the success and failure groups. The human acellular dermal allograft and paper-patch groups showed no significant difference in the recovery confirmation time (70.7 ± 42.3 vs. 89.9 ± 119.4 days, P = .486) and recovery rate (95.5% vs. 85.0%, P = .333). However, the patch maintenance time of the human acellular dermal allograft group was statistically longer than the paper-patch group (32.9 ± 14.9 vs. 15.6 ± 19.9 days, P = .001). On multivariable regression analysis, patch material was the only parameter associated with patch maintenance time (P = .002). Treatment outcomes of traumatic tympanic membrane perforation using human acellular dermal allograft showed better or similar therapeutic efficacy compared to paper patch. The important advantage of this material is to stay in situ for a sufficient time without being detached until successful healing.

Dermal exposure assessment to trinexapac-ethyl: a case study of workers in golf course in Hawaii, USA.

Trinexapac-ethyl (TE) was more widely used in golf course worldwide. As a plant growth regulator, it inhibited grass development and delayed grass cutting date. Direct contact with TE by workers that handle and apply these agents can lead to harmful effects depending on the exposure dosage and duration. Many studies have focused on the growth regulation of TE in plants, while its health risks to human beings were rarely reported. Here, we investigated the risk assessment of workers directly dermal exposed to TE by using some absorbent paper patches. The exposure intensity (EI) and potential dermal exposure (PDE) of worker body sections were obtained, and different exposure patterns were compared. The EI of each body section among mixing/loading, hand-held power sprayer, and manual sprayer workers was ranging from 7.22 to 73.0 pg cm-2. The maximum EI of TE was found on hands of manual sprayers, while the minimum EI of TE was recorded on upper arms of mixing and loading workers. The maximum contribution sections was 29% for the chest and back from mixing/loading workers, 40% for the chest and back from hand-held power sprayers, and 32% for the thigh from manual sprayers. The unit weight potential dermal exposure (UWPDE) of hand-held power sprayers was 60% lower than that of manual sprayers, indicating that hand-held power sprayers were safer than those of manual sprayers. These findings revealed that trinexapac-ethyl posed relatively higher exposure risks to manual sprayer workers than other operator workers in golf course, mainly responsible for body sections of the chest and back and thigh.

Configurable 2D nano-flows in mesoporous films using paper patches.

Designing and controlling spontaneous imbibition is becoming a key requirement for advanced devices, presenting a substantial scientific and engineering challenge. Here we describe an approach that allows directional imbibition into designed geometries. A set of custom domains based on paper microfluidics mold nano-imbibition in user-defined shapes such as curvatures, corners, and vertices into mesoporous thin films; enabling localized chemical reactions with programmable designs. The method also achieves nano-size filtration, allows the generation and delivery of reagent gradients in a nanofluidic fashion, and it can be used as a reactor for the synthesis of patterned metallic nanoparticle arrays. By using this easy-to-build hybrid platform, users can create functional nanofluidic domains in custom geometries and perform spatially shaped chemistry. The ability to integrate mesoporous nanofluidic generation and paper-based microfluidics has made the hybrid system an exciting candidate for versatile nanoflow applications.

Fast mixing of metropolis-hastings with unimodal targets

A well-known folklore result in the MCMC community is that the Metropolis-Hastings algorithm mixes quickly for any unimodal target, as long as the tails are not too heavy. Although we’ve heard this fact stated many times in conversation, we are not aware of any quantitative statement of this result in the literature, and we are not aware of any quick derivation from well-known results. The present paper patches this small gap in the literature, providing a generic bound based on the popular “drift-and-minorization” framework of [19]. Our main contribution is to study two sublevel sets of the Lyapunov function and use path arguments in order to obtain a sharper bound than what can typically be obtained from multistep minorization arguments.

Novel transparent collagen film patch derived from duck’s feet for tympanic membrane perforation

To increase healing rate of tympanic membrane (TM) perforations, patching procedure has been commonly conducted. Biocompatible, biodegradable patching materials which is not limited across cultures is needed. The authors evaluated the effectiveness of novel transparent duck’s feet collagen film (DCF) patch in acute traumatic TM perforation. This procedure was compared with spontaneous healing and paper patching. Cell proliferation features were observed in paper and DCF patches. Forty-eight TMs of 24 rats were used for animal experiment, perforations were made on each TMs, and divided into three groups according to treatment modality. Sixteen were spontaneously healed, 16 were paper patched and 16 were DCF patched. The gross and histological healing results were analyzed. Both paper and DCF patch showed no cytotoxicity, but cell proliferations were more active in DCF than paper in early stage. In animal study, the healing of TM perforations were completed within 14 days in all three groups, but found to be faster in DCF patch group than paper patch or spontaneous healing group. The DCF patches were transparent and size of DCF patches were gradually decreased, so there were no need to remove the DCF patches to check the wound status or after the completion of healing. According to this result, authors concluded that DCF patch is transparent, biocompatible and biodegradable material, and can induce fast healing in acute traumatic TM perforations.

Minimally invasive transcanal myringotomy for pediatric early stage congenital cholesteatoma

ObjectiveRecently, minimally invasive transcanal myringotomy (MITM), which is a useful surgical technique for early stage congenital cholesteatoma (CC) in children, was introduced. The purpose of this study is to evaluate the short-term surgical results of MITM in pediatric early stage CC. Materials and methodsWe retrospectively reviewed the charts of 24 patients who underwent MITM between January 2013 and October 2015. ResultsThe patients' ages ranged from 1 to 16 years (mean, 2.6 years). There were 17 male and 7 female patients. The right side (n = 13) was affected twice as often as the left side (n = 11). The most common site was the anterosuperior quadrant (15 cases). The diameter of the CC on axial computed tomography images ranged from 2.8 to 5.7 mm (mean, 3.9 mm). CCs were graded according to Potsic's system: 18 cases were classified as stage I, 3 case as stage II, and 3 cases as stage III. AllCCs except 1 were closed type. In21 patients, the tympanic membrane closed naturally without recurrence. Three patients showed small persistent dry perforation. Natural closure occurred in these patients, who were treated with paper patches. ConclusionMITM is a simple, effective technique for removing an early stage CC from the middle ear, and it can minimize operative time, length of hospitalization, and postoperative morbidity.

Paper patching of the tympanic membrane as a symptomatic treatment for patulous Eustachian tube syndrome

Aim of the study Autophony and other symptoms in patients suffering form patulous Eustachian tube syndrome have been found to respond to application of Steri-strips and clay on the tympanic membrane. We used small paper patches that were applied on specified locations on the tympanic membrane. Material and methods The charts of 21 patients treated for patulous Eustachian tube syndrome between 2006 and 2011 were studied for subjective improvement of symptoms following the application of paper patches. Results Paper patching of the tympanic membrane provided symptomatic relief in 76.2 percent of patients; relief was permanent in 50 percent of these patients. These results are similar to the ones obtained with much heavier materials. The specific location appears to be important. Our results suggest the existence of two clinically separate subgroups in patulous Eustachian tube. Conclusion Paper patching of the tympanic membrane is a simple and effective means of temporarily or permanently alleviating patulous Eustachian tube syndrome symptoms. It is postulated that the patches decrease the admittance of low- to mid-frequency acoustic input at the tympanic membrane by increasing the stiffness of the tympanic membrane, thereby counteracting the middle-ear cushion effect caused by the open Eustachian tube.

BurnCalc assessment study of computer-aided individual three-dimensional burn area calculation.

BackgroundAccurate estimation of a burned area is crucial to decisions about fluid resuscitation, surgical options, nutritional support, and prognosis. Widely used clinical methods to estimate a burn area are two-dimensional. They do not consider age, sex, body mass, physical deformities, or other relevant factors. Computer-aided methods have improved the accuracy of estimating burned areas by including data analysis and reducing subjective differences. Three-dimensional (3D) scanning allows us to determine body dimensions rapidly and reproducibly. We describe an individualized, cost-efficient, portable 3D scanning system, BurnCalc, that can create an individual 3D model and then calculate body surface area (BSA) and the burn area accurately and quickly.MethodsThe BurnCalc system was validated by verifying the accuracy and stability of BSA calculation. We measured 10 regular objects in experiment 1, using Student’s t-test and the intraclass correlation coefficient (ICC) in the analysis. In experiment 2, artificial paper patches of known dimensions were attached to various parts of the body of 40 volunteers. Their sizes were then calculated using BurnCalc. The BurnCalc data were compared to actually measured values to verify accuracy and stability. Total BSAs of these 40 volunteers were also calculated by BurnCalc and compared to those derived from an accepted formula. In experiment 3, four experts using Chinese Rule-of-Nines or Rule-of-Palms methods calculated the percentages of the total BSA in 17 volunteers. Student’s t-test and ICC, respectively, were used to compare the results obtained with the BurnCalc technique.ResultsStatistically, in experiment 1, p = 0.834 and ICC = 0.999, demonstrating that there was no difference between the BurnCalc and real measurements. Also, the hypothesis of null difference among measures (experiment 2) was true because p > 0.05 and ICC = 0.999, indicating that calculations of the total BSA and the burn area were more accurate using the BurnCalc technology. The reliability of the BurnCalc program was 99.9%. In experiment 3, only the BurnCalc method exhibited values of p > 0.05 (p = 0.774) and ICC = 0.999.ConclusionsBurnCalc technology produced stable, accurate readings, suggesting that BurnCalc could be regarded as a new standard clinical method.

Paper patching of the tympanic membrane as a symptomatic treatment for patulous eustachian tube syndrome

Application of one or several paper patches on the tympanic membrane can improve autophony and other symptoms in some patients with a patulous eustachian tube. The charts of 21 patients treated for patulous eustachian tube syndrome between 2006 and 2011 were studied for subjective improvement of symptoms following the application of paper patches. Paper patching of the tympanic membrane provided symptomatic relief in 76.2 per cent of patients; relief was permanent in 50 per cent of these patients. Paper patching of the tympanic membrane is a simple and effective means of temporarily or permanently alleviating patulous eustachian tube syndrome symptoms. It is postulated that the patches decrease the admittance of low- to mid-frequency acoustic input at the tympanic membrane by increasing the stiffness of the tympanic membrane, thereby counteracting the middle-ear cushion effect caused by the open eustachian tube.

A sequential machine vision procedure for assessing paper impurities

We present a sequential, two-step procedure based on machine vision for detecting and characterizing impurities in paper. The method is based on a preliminary classification step to differentiate defective paper patches (i.e., with impurities) from non-defective ones (i.e., with no impurities), followed by a thresholding step to separate the impurities from the background. This approach permits to avoid the artifacts which occur when thresholding is applied to paper samples that contain no impurities. We discuss and compare different solutions and methods to implement the procedure and experimentally validate it on a datasets of 11 paper classes. The results show that a marked increase in detection accuracy can be obtained with the two-step procedure in comparison with thresholding alone.

Automatic Paper Sliceform Design from 3D Solid Models

A paper sliceform or lattice-style pop-up is a form of papercraft that uses two sets of parallel paper patches slotted together to make a foldable structure. The structure can be folded flat, as well as fully opened (popped-up) to make the two sets of patches orthogonal to each other. Automatic design of paper sliceforms is still not supported by existing computational models and remains a challenge. We propose novel geometric formulations of valid paper sliceform designs that consider the stability, flat-foldability and physical realizability of the designs. Based on a set of sufficient construction conditions, we also present an automatic algorithm for generating valid sliceform designs that closely depict the given 3D solid models. By approximating the input models using a set of generalized cylinders, our method significantly reduces the search space for stable and flat-foldable sliceforms. To ensure the physical realizability of the designs, the algorithm automatically generates slots or slits on the patches such that no two cycles embedded in two different patches are interlocking each other. This guarantees local pairwise assembility between patches, which is empirically shown to lead to global assembility. Our method has been demonstrated on a number of example models, and the output designs have been successfully made into real paper sliceforms.

Biocompatibility evaluation of cigarette and carbon papers used in repair of traumatic tympanic membrane perforations: experimental study

The purposes of this study were to investigate the biocompatibility of two different paper patches (carbon and cigarette papers) and compare the adhesion and proliferation features of L929 fibroblast cells by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT Test) test and scanning electron microscopy (SEM). In this study, time-dependent cytotoxic effects of cigarette and carbon papers used in repairing small traumatic TM perforations were investigated in vitro by using MTT test. And also adhesion and spreading of cells over disk surface were observed by SEM. Cytotoxicity test carried out by MTT analysis on leakage products collected from two types of paper patches at the end of 24 and 48 h revealed no cytotoxicity (P > 0.05). In SEM studies, it was observed that cells started to proliferate over disk surface as a result of 48-h incubation, and SEM revealed that the cell proliferation over cigarette paper was more compared to the one over carbon paper. We believe that this is the first study where biocompatibility and adhesion features of carbon and cigarette paper have been studied by using L929 fibroblast cell culture. As a result, biocompatibility of cigarette paper and also whether cigarette paper was superior to carbon paper in cell attachment and biocompatibility were studied. It was found, by MTT test and SEM test, that cigarette paper had a higher biocompatibility and cell attachment, and thus cigarette paper should be the patch to be preferred in cases where TM perforations are repaired by paper-patch method.

A system for 3D representation of burns and calculation of burnt skin area

In this paper a computer-based system for burnt surface area estimation (BAI), is presented. First, a 3D model of a patient, adapted to age, weight, gender and constitution is created. On this 3D model, physicians represent both burns as well as burn depth allowing the burnt surface area to be automatically calculated by the system. Each patient models as well as photographs and burn area estimation can be stored. Therefore, these data can be included in the patient's clinical records for further review. Validation of this system was performed. In a first experiment, artificial known sized paper patches were attached to different parts of the body in 37 volunteers. A panel of 5 experts diagnosed the extent of the patches using the Rule of Nines. Besides, our system estimated the area of the “artificial burn”. In order to validate the null hypothesis, Student's t-test was applied to collected data. In addition, intraclass correlation coefficient (ICC) was calculated and a value of 0.9918 was obtained, demonstrating that the reliability of the program in calculating the area is of 99%. In a second experiment, the burnt skin areas of 80 patients were calculated using BAI system and the Rule of Nines. A comparison between these two measuring methods was performed via t-Student test and ICC. The hypothesis of null difference between both measures is only true for deep dermal burns and the ICC is significantly different, indicating that the area estimation calculated by applying classical techniques can result in a wrong diagnose of the burnt surface.

Tympanic Membrane Regeneration Using a Water-Soluble Chitosan Patch

Chronic otitis media or tympanic membrane (TM) perforation is one of the most common otologic diseases. Surgical tympanoplasty remains the best treatment option despite the fact that paper patches are frequently used. Although paper patches are not biocompatible or effective, tympanoplasty is an expensive, complex surgery. Tissue engineering techniques offer a new treatment strategy for TM regeneration. In this study, novel tissue-engineered artificial eardrums were fabricated from water-soluble chitosan, which is known to be a good wound-healing biomaterial. The characteristics, cytotoxicity, and healing effects of several water-soluble chitosan patches (WSCPs) made using various concentrations of water-soluble chitosan and glycerol were investigated. The optimal WSCP was fabricated with 3% water-soluble chitosan and 3% glycerol, and it had a thickness of about 35 mum, a tensile strength of 7 MPa, a percent elongation of 101%, a hydrophilic surface, and no cytotoxicity. In vivo studies showed that the WSCPs were more effective than spontaneous healing for the repair of traumatic TM perforations. The healed TMs to which WSCPs were applied had a much higher density of collagen fibers and a better lamina propria layer structure than spontaneously healed TMs.

Development of water‐insoluble chitosan patch scaffold to repair traumatic tympanic membrane perforations

Perforated tympanic membranes (TM) and otitis media can be managed with a paper patch or tympanoplasty. However, a paper patch is not biocompatible and tympanoplasty requires complex aseptic surgical procedures. A novel biocompatible patch with a water-insoluble chitosan as the main component was prepared. Optimal mechanical characteristics of a water-insoluble chitosan patch scaffold (CPS) was approximately 40 microm in thickness, 7 MPa in tensile strength, and 107% in percent elongation, even though the characteristics varied significantly depending on the concentrations of chitosan and glycerol. SEM of the CPSs showed a very smooth surface as compared with that of the paper patches. These CPSs showed no cytotoxicity and had a stimulating effect on the proliferation of TM cells in in vitro study. In in vivo study, 4 (21.1%) and 17 (89.5%) TMs out of 19 adult rats with CPSs showed no perforations at 1 and 2 weeks, respectively. However, left control TMs showed healing of 0 (0%) at 1 week and 18 (94.7%) at 2 weeks. TEM findings of regenerated eardrums using CPSs showed thinner, smoother, and more compact tissues than spontaneously healed eardrums. A CPS was more effective than spontaneous healing to repair traumatic TM perforations.

Tympanic Membrane Collagen Fibers: A Key to High‐Frequency Sound Conduction

To investigate the significance of tympanic membrane collagen fiber layers in high frequency sound transmission. Human cadaver temporal bone study. Laser Doppler vibrometry was used to measure stapes footplate movement in response to acoustic stimulation. The tympanic membrane was altered by creating a series of slits and applying paper patches to isolate the effects of specifically oriented collagen fibers. Three groups of membrane alterations were evaluated: 1) circumferentially oriented slits involving each quadrant to primarily disrupt radial fibers, made sequentially within superior-anterior, inferior-anterior, inferior-posterior, and superior-posterior quadrants; 2) the same slits made in the reverse order; and 3) radially oriented slits from the umbo to the annulus to primarily disrupt circumferential fibers. For each group, measurements of the middle-ear cavity pressure, ear canal pressure, and stapes velocity were made each time the tympanic membrane was altered. Regardless of the order in which the circumferentially oriented slits were made, there was a consistent decrease in stapes velocity above 4 kHz for the third and fourth cuts compared to the control. The mean decrease in the range of 4 to 12.5 kHz was 11 dB for the third patched slit and 14 dB for the fourth patched slit (P < .01). Radially oriented slits appear to produce smaller effects. Radial collagen fibers in the tympanic membrane play an important role in the conduction of sound above 4 kHz.

Two new methods for clothing tympanic membrane perforations

Tympanic membrane (TM) perforations can be closed in the outpatient clinic using a variety of materials, such as fascia, fat, connective tissue, paper patches, and Gelfoam. Such minimally invasive surgery or conservative treatment is especially effective when the perforation is small, fresh, and dry. However, in some cases, these procedures fail to close a perforation, mainly because of decreased regeneration activity of the TM at the margin of the perforation. To improve the success rate of conservative treatment, we applied two new methods: using basis fibroblast growth factor (bFGF) combined with atelocollagen/silicon bilayer membranes as a patch material, and using amniotic membrane combined with amniotic membrane.

Rate of persistent perforation after elective tympanostomy tube removal in pediatric patients

This study was performed to determine the rate of persistent perforations according to age, tube type and duration of intubation in children who underwent elective tympanostomy tube removal. Our retrospective analysis of hospital and clinic charts included all patients who underwent elective tube removal from July 1995 to December 1997 at our institution. Information from the chart review included patient age at time of tube removal, type of tube removed, duration of intubation, presence of granulation tissue/polyps, and concomitant paper patch placement. The outcome of each surgical removal was determined by examining follow-up clinic charts. A patient was deemed to have a persistent perforation if the eardrum had not adequately healed within 3 months after surgery. Data on 201 patients were gathered. These patients had 273 tube removals. Eleven percent of ears (29/273) had persistent perforations. According to tube type, no perforations (0/48) occurred with Collar Bobbin tubes, 6% (3/50) with Tytan tubes, 7% (3/44) with Duravent tubes, and 22% (16/74) with Paparella II tubes. Three percent (3/101) of tubes in place for <3 years and 15% (26/172) of tubes in place for >3 years showed persistent perforations after removal. Ears with granulation polyps had a 9% (18/203) rate of perforations, whereas those without granulation polyps had a 16% (11/70) rate of perforations. Forty percent (4/10) of ears were treated with paper patches at the time of tube removal showed persistent perforations. Our data indicate that the rate of persistent perforation (11%) after elective tympanostomy tube removal is high. The factors associated with higher rates of persistent perforation ( P<0.05) include duration of intubation >3 years prior to removal and the use of long-term Paparella II tubes.

The repair of parchlllent: Filling

Parchment is produced by processing the dermal layer of animal hide through limited mechanical and chemical treatment and then drying it under tension. The weak condition of many historical objects made of this material is caused by chemical, biological and mechanical degradation. Repairing these objects by filling gaps with parchment or paper patches may be inadvisable, due to important differences in intrinsic strength, which can create tensions between old and new materials. Alternative filling methods may be used, consisting of the application of solid materials in the form of a powder or a suspension, used to create a solid sheet of reconstituted parchment. The solids may consist of any kind of collagenous material (powdered parchment or hide, gelatin), paper or a combination of the two. Published methods describe preliminary treatments (e.g.relaxation), application media (water, solvents, additives), use of additional consolidating membranes (Japanese paper, goldbeater's skin), use of adhesives for pasting and surface consolidation purposes, preparation of mechanically isotropic templates for infills and tinting with synthetic dyes. A comparative investigation of methods confirms that the mechanical properties achieved in these infills, such as tensile strength and elasticity, as well as their reproducibility, are acceptable for application in conservation practice.