Microstructure and physical properties of clayey-ceramic materials with lightweight mineral additives

Low density ceramic structures have an important place in application areas such as heat, noise and noise insulation. Besides, being durable and inexpensive is also a demand for producers and consumers. In this study, it is aimed to produce lightweight insulation ceramic materials from a binder clay containing diatomite and vermiculite raw materials in different proportions which is a local and natural mineral raw material source for low temperature applications. For this purpose, firstly, powdered raw materials is characterized for particle size distribution, chemical composition (x-ray fluorescence, XRF), thermal behavior (thermal gravimetric analysis, TGA), morphological structure (scanning electron microscope, SEM) and crystal phase structure (x-ray diffraction, XRD). Specific prescriptions were then prepared and pellet samples were obtained using the pressing method. The bulk density and porosity, dimensional changes, thermal conductivity coefficients and microstructural properties of the samples fired at temperatures between 900, 1000 and 1100 °C were compared. As a result of the study, the porosity of the ceramic samples containing 60% diatomite, 10% vermiculite and 30% binder clay increased up to 47%, while the bulk density values were obtained at 1.3 g/cm3 and the thermal conductivity coefficient was at 0.439 W / mK

The investigation of repair time and the effect of melatonine in healing of repaired peripheral nerve injury

Travma sonucu meydana gelen periferik sinir hasarı, fiziksel olduğu kadar psikososyal ve ekonomik problemlere de yol açan ciddi bir durumdur. İyileşme süreci oldukça uzundur ve ciddi fonksiyon kayıplarına neden olmaktadır. Günümüzde bile mükemmel duyusal ve fonksiyonel olarak geri dönüşü sağlayabilecek bir tedavi şekli ortaya konamamıştır.Periferik sinir cerrahisinde onarım zamanlamasının önemi herkesçe kabul görmektedir. Bununla birlikte pek çok farmakolojik ajan deneysel olarak, hücre ölümünü azaltmak ve sinir iyileşmesini hızlandırmak amacıyla kullanılmıştır. Ancak hali hazırda klinik kullanıma giren bir ajan mevcut değildir. Bu bilgiler ışığında deneysel olarak oluşturulan siyatik sinir kesisinde farklı onarım zamanlarında melatoninin sinir iyileşmesine olan etkisini araştırmak ve bu etkileri stereolojik olarak değerlendirerek kantitatif veriler elde etmek amacıyla bu çalışma planlandı.Çalışmada toplam 80 adet Wistar cinsi dişi rat kullanıldı. Onarım zamanları 0. saat, 12. saat, 24. saat ve 1. hafta olarak belirlendi. İlk dört gruba (Grup 1, 2, 3, ve 4) sinir kesisi sonrası 12 hafta boyunca intraperitoneal olarak Melatonin verildi ve belirlenen zamanlarda onarım yapıldı. İkinci dört gruba (Grup 5, 6, 7 ve 8) siyatik sinir kesisini takiben belirlenen zamanlarda onarım yapıldı. 12. hafta sonunda miyelinli akson sayıları değerlendirildi. Erken onarım yapılan gruplarda istatistiksel olarak anlamlı düzeyde fark tespit edildi (p<0.05). Melatonin verilen gruplardan elde edilen akson sayılarının verilmeyenlere göre istatistiksel olarak anlamlı düzeyde farklı olduğu tespit edildi (p<0.05). Ayrıca Melatoninin onarım zamanlarına göre akson sayıları arasındaki farkı ortadan kaldırdığı gözlendi.Sonuç olarak periferik sinir kesilerinde erken onarım sinir iyileşmesinde iyi sonuçlar alınmasında etkilidir ancak yeterli değildir. Çalışmamızda erken onarıma ek olarak melatonin kullanımı deneysel olarak akson rejenerasyonunu artırmıştır. Ayrıca erken dönemde sinir onarımının mümkün olmadığı durumlarda melatonin uygulaması bekleme sürecinde akson yaşayabilirliğini artırarak ve güçlü antioksidan etkisiyle kesilen sinirdeki hasarı azaltarak akson rejenerasyonuna pozitif yönde katkıda bulunabilmektedir.Periferic nerve injury is a serious causes economic and psychosocial problems, which happens as a result of trauma. Healing period is fairly long and causes serious functional losses. Recently no treatment method presents to provide recovery as perfect sensational and functional.It?s all agreed that the importance of repair timing in periferic nerve surgery. However most pharmacological agent was used to accelerate nerve healing and reduce cell death as experimental. But currently there is no agent which enters clinic usage. In the light of these data, this study is planned to acquire quantitative data which evaluate these effects as stereologic and to search the influence of nerve healing of melatonin in different repair times at sciatic nerve cut formed as experimental.In this study total 80 Wistar female rats are used. Repair times are determined as 0. hour, 12. hour, 24. hour and 1. week. After nerve cut during 12 weeks as intraperitoneal melatonin was given to the first four groups ( Group 1, 2, 3 and 4) and repair was made at determined times. Repair was made to the second four gruops (Group 5, 6, 7 and 8) at determined times following sciatic nerve cut. The end of 12.week the axon numbers with miyelin was evaluated. Significantly difference was stated as statistical in the groups that made early repair. (p <0.05). It?s stated that the axon numbers acquired from the groups given melatonin are significantly different from the ones not given melatonin as statistical. (p<0.05). Besides melatonin removes the difference of axon numbers according to their repair times.As a result early repair in periferic nerve cut is effective in nerve healing to take good results but it?s not sufficient. In our study in addition to early repair the usage of melatonin increases axon regeneration as experimental. Moreover melatonin application increases axon viability at waiting time in case of there is no possible early period nerve repair. It contributed to axon regeneration to increase the damage of nerve cut by the influence of strong antioxidant

A rare condition to keep in mind: Pyoderma gangrenosum after breast reduction

yoderma gangrenosum is a rare inflammatory disease, characterized by ulcers with purple-colored borders and elythematous halo. Clinically, the patient has fever and severe local pain. Pyoderma gangrenosum can occur after any surgical procedure and the diagnosis is usually delayed. It is important for surgeons and infectologists to be watchful about this rare condition because if misdiagnosed, it has serious results including severely painful ulcerations, prolonged therapy, repeated hospitalizations, psychological trauma, and extensive scarring. The authors report a postsurgical pyoderma gangrenosum case after reduction mammoplasty. This report emphasizes on the importance of awareness about this uncommon disease and its diagnosis

Exposure to tumescent solution significantly increases phosphorylation of perilipin in adipocytes

BACKGROUND: Lidocaine and epinephrine could potentially decrease adipocyte viability, but these effects have not been substantiated. The phosphorylation status of perilipin in adipocytes may be predictive of cell viability. Perilipin coats lipid droplets and restricts access of lipases; phospho-perilipin lacks this protective function.OBJECTIVES: The authors investigated the effects of tumescent solution containing lidocaine and epinephrine on the phosphorylation status of perilipin in adipocytes.METHODS: In this in vitro study, lipoaspirates were collected before and after tumescence from 15 women who underwent abdominoplasty. Fat samples were fixed, sectioned, and stained for histologic and immunohistochemical analyses. Relative phosphorylation of perilipin was inferred from pixel intensities of immunostained adipocytes observed with confocal microscopy.RESULTS: For adipocytes collected before tumescent infiltration, 10.08% of total perilipin was phosphorylated. In contrast, 30.62% of total perilipin was phosphorylated for adipocytes collected from tumescent tissue (P < .01).CONCLUSIONS: The tumescent technique increases the relative phosphorylation of perilipin in adipocytes, making these cells more vulnerable to lipolysis. Tumescent solution applied for analgesia or hemostasis of the donor site should contain the lowest possible concentrations of lidocaine and epinephrine. LEVEL OF EVIDENCE 5

Necessity of suction drains in gynecomastia surgery

Background: The aim of gynecomastia surgery is to restore a normal chest contour with minimal signs of breast surgery. Objective: The authors examine the rate of complications in gynecomastia surgery when no closed-suction drains are placed. Methods: One hundred thirty-eight consecutive male patients who underwent gynecomastia surgery without drains were retrospectively analyzed to determine whether the absence of drains adversely affected patient outcomes. Patients were managed by ultrasonic-assisted liposuction both with and without the pull-through technique. Results: The mean age of the patients was 29 years, and the mean volume of breast tissue aspirated was 350 mL per beast. Pull-through was needed in 23 cases. There was only 1 postoperative hematoma. Conclusions: These results are comparable with previously published data for gynecomastia surgery in which drains were placed, suggesting that the absence of drains does not adversely affect postoperative recovery. Routine closed-suction drainage after gynecomastia surgery is unnecessary, and it may be appropriate to omit drains after gynecomastia surgery

L’utilisation de plasma riche en plaquettes pour conserver des greffons de peau exc´edentaires

WOS: 000403052800007PubMed ID: 29026811Background:There is a need for improved methods and storage media to sustain the tissue viability of autologous skin grafts.Objective:To compare histological changes in human skin grafts stored in platelet-rich plasma (PRP) with those of grafts stored in saline.Methods:Eight circular, 3-mm full-thickness skin graft samples were harvested from the abdominal skin of each of 5 patients scheduled to undergo an abdominoplasty procedure. Four of these graft samples were stored in saline, and the other 4 were stored in saline mixed with PRP prepared from the patient's own venous blood. Histological assessment of the microscopic appearance of the samples was performed on days 5, 8, 11, and 14. The integrity of the epidermal-dermal junction, number of keratinocytes with perinuclear halos, collagen organization, and number of fibroblasts per field were assessed. The cellular apoptosis rate was also measured on these same days.Results:On day 5, significant differences were observed microscopically between the PRP-and saline-stored grafts (P < .05). The grafts preserved in saline exhibited early marked cellular and nuclear swelling with pleomorphism, as well as early nuclear halo formation. The cell viability rate of the PRP group was significantly higher than that of the saline-stored group on day 8 (P < .05).Conclusion: Platelet-rich plasma and its inherent growth factors supported longer graft survival; however, its effect lasted only until day 8. Platelet-rich plasma may be beneficial if grafts need to be stored for delayed application(s).Historique : Il faut am´eliorer les m´ethodes et les milieux de conservation pour maintenir la viabilit´e des greffons autologues de peau. Objectif : Comparer les changements histologiques des greffons de peau humaine conserv´es dans du plasma riche en plaquettes (PRP) a ` ceux des greffons conserv´es dans un solut´e physiologique. M´ethodologie : Les chercheurs ont pr´elev´e huit ´ echantillons de greffons circulaires de trois millime `tres de peau pleine ´epaisseur sur la peau de l’abdomen de chacun des cinq patients qui devaient subir une abdominoplastie. Quatre d’entre eux ont ´ et´e conserv ´ es dans un solut´e physiologique et les quatre autres, dans un solut´e physiologique m´elang´ea ` du PRP pr´epar´ea ` partir du propre sang veineux du patient. Les chercheurs ont proc´ed´ea ` l’´evaluation histologique de l’aspect microscopique des ´echantillons les cinquie `me, huitie `me,onzie `me et quatorzie `me jours apre `s le pr ´ ele `vement. Ils ont examin´e l’int ´ egrit´e de la jonction dermo´epidermique, le nombre de k´eratinocytes dot´es de halos p´erinucl´eaires, l’organisation du collage `ne et le nombre de fibroblastes par champ. Les mˆemes jours, ils ont mesur´e le taux d’apoptose cellulaire. R´esultats : Le cinquie `me jour, les chercheurs ont observ´e des diff´erences microscopiques significatives entre les greffons conserv´es dans le PRP et ceux conserv´es dans un solut´e physiologique (P<0,05). Les greffons conserv´es dans le solut´e physiologique pr´esentaient une hypertrophie cellulaire et nucl´eaire pr´ecoce marqu´ee accompagn´ee de pl´eomorphisme ainsi que la formation pr´ecoce de halos nucl´eaires. Le huitie `me jour, le taux de viabilit´e des cellules du groupe de PRP ´etait consid´erablement plus ´elev´e que celui des cellules du groupe de solut´e physiologique (P<0,05). Conclusion : Le plasma riche en plaquettes et les facteurs de croissance inh´erents favorisaient une plus longue survie, mais seulement jusqu’au huitie `me jour. Le plasma riche en plaquettes peut ˆetre b´en´efique si les greffes doivent ˆetre conserv´ees en vue d’ˆetre utilis´ees plus tard

"Abdominoplasty with "En block" removal of the skin island: A safe and fast approach"

The aim of abdominoplasty is to restore a normal abdominal contour, with minimal signs of the surgery. The purpose of this study was to determine the feasibility, safety, and advantages of en block removal of a skin island before upper abdominal dissection during abdominoplasty. Five hundred-forty female patients who underwent abdominoplasties between January 2004 and December 2018 were retrospectively analyzed. In these cases, the planned skin resection was initially made en block, as done with an elliptic skin excision. In this way, symmetric skin removal is achieved. After the removal of this skin, epigastric skin undermining was easily achieved. The mean age of the patients was 41.4 y, and the mean body mass of index was 27.3 kg/m(2). The mean operative time for abdominoplasty only was 98 min. Eight patients had minor skin problems, 22 patients needed aspiration for seroma formation, and 7 patients needed scar revision surgery. There was only one hematoma postoperatively. The final position of the scar from the upper vulvar commissure was 8.9 cm. The results obtained were comparable to those of classical abdominoplasty, suggesting that en block removal of the skin before upper flap dissection is a safe maneuver. En block removal of skin island at the start of the surgery has the added advantage of a reduced operative time and acceptable aesthetic outcome, without an increase in complication rates. In cases of planned abdominoplasties, we suggest that removal of the abdominal skin at the beginning of the operation is a safe and feasible procedure