Application of fiber loop ringdown spectroscopy technique for a new approach to beta-amyloid monitoring for Alzheimer Disease's early detection.

A novel fiber optic biosensor was purposed for a new approach to monitor amyloid beta protein fragment 1-42 (Aß42) for Alzheimer's Disease (AD) early detection. The sensor was fabricated by etching a part of fiber from single mode fiber loop in pure hydrofluoric acid solution and utilized as a Local Optical Refractometer (LOR) to monitor the change Aß42 concentration in Artificial Cerebrospinal Fluid (ACSF). The Fiber Loop Ringdown Spectroscopy (FLRDS) technique is an ultra-sensitive measurement technique with low-cost, high sensitivity, real-time measurement, continuous measurement and portability features that was utilized with a fiber optic sensor for the first time for the detection of a biological signature in an ACSF environment. Here, the measurement is based on the total optical loss detection when specially fabricated sensor heads were immersed into ACSF solutions with and without different concentrations of Aß42 biomarkers since the bulk refractive index change was performed. Baseline stability and the reference ring down times of the sensor head were measured in the air as 0.87% and 441.6µs ± 3.9µs, respectively. Afterward, the total optical loss of the system was measured when the sensor head was immersed in deionized water, ACSF solution, and ACSF solutions with Aß42 in different concentrations. The lowest Aß42 concentration of 2 ppm was detected by LOR. Results showed that LOR fabricated by single-mode fibers for FLRDS system design are promising candidates to be utilized as fiber optic biosensors after sensor head modification and have a high potential for early detection applications of not only AD but possibly also several fatal diseases such as diabetes and cancer.

Spatial Growth Factor Delivery for 3D Bioprinting of Vascularized Bone with Adipose-Derived Stem/Stromal Cells as a Single Cell Source.

Encapsulating multiple growth factors within a scaffold enhances the regenerative capacity of engineered bone grafts through their localization and controls the spatiotemporal release profile. In this study, we bioprinted hybrid bone grafts with an inherent built-in controlled growth factor delivery system, which would contribute to vascularized bone formation using a single stem cell source, human adipose-derived stem/stromal cells (ASCs) in vitro. The strategy was to provide precise control over the ASC-derived osteogenesis and angiogenesis at certain regions of the graft through the activity of spatially positioned microencapsulated BMP-2 and VEGF within the osteogenic and angiogenic bioink during bioprinting. The 3D-bioprinted vascularized bone grafts were cultured in a perfusion bioreactor. Results proved localized expression of osteopontin and CD31 by the ASCs, which was made possible through the localized delivery activity of the built-in delivery system. In conclusion, this approach provided a methodology for generating off-the-shelf constructs for vascularized bone regeneration and has the potential to enable single-step, in situ bioprinting procedures for creating vascularized bone implants when applied to bone defects.

The effect of taurine on flap perfusion and viability in random pattern flaps in rats.

BACKGROUND: In present study, the effect of taurine on flap perfusion and viability was examined using the modified random pattern dorsal flap model (DFM). MATERIALS AND METHODS: Eighteen rats were included and divided equally (n=9) to taurine treatment and control groups in this study. Taurine treatments were given orally at a dose of 100 mg/kg/day. Taurine group received taurine, starting 3 days before the operation till the postoperative 3rd day. Angiographic images were recorded when the flaps were sutured back and on postoperative 5th and 7th days. Necrosis calculations were made with all the images obtained by the digital camera and the indocyanine green angiography. Fluorescence intensity, fluorescence filling rate and flow rate of DFM were calculated by the SPY device and the SPY-Q software. All flaps were analyzed histopathologically, also. RESULTS: Perioperative taurine treatment significantly reduced necrosis rates and increased the fluorescence density, the fluorescence filling rate and the flap filling rates in the DFM (p<0.05). Reduced amounts of necrosis, ulcer and polymorphonuclear leukocyte supported the beneficial effect of taurine histopathologically (p<0.05). CONCLUSIONS: Taurine may be used as an effective medical agent for prophylactic treatment options in flap surgery.

Technical details for inset of flaps in transfer of double-level gastroepiploic lymph node flaps for lower extremity lymphedema.

BACKGROUND: In this study, the method that can be followed to ensure rapid and uncomplicated recovery of lymph node flap (LNF) applied in the medial of the ankle for lymphedema treatment was investigated. METHODS: Thirty-seven patients with class II of lower limb lymphedema underwent transfer of gastroepiploic LNF to the medial ankle and popliteal fossa areas. At the popliteal fossa region, the wound could always be closed primarily by the advancement of neighboring skin. The wound closure could be classified into three types at the medial ankle area (A) The partially exposed LNF was covered with a split-thickness skin graft (STSG) (n = 9). (B) A larger local flap was elevated, and the donor site of the local flap was covered with STSG (n = 18). (C) The skin flap's donor site was treated with pre-tie sutures (n = 10). RESULTS: In the popliteal region, there was no complication of wound healing. In the ankle region, the wound was coated by a thin layer of hematoma over the exposed LNF in 5 patients of group A. It healed secondarily except for one patient who needed a secondary skin graft. The healing was perfect in group B. In group C the healing was good, but there was a hypertrophic scar in 7 patients and required steroid injection later. CONCLUSION: To avoid complications of the gastroepiploic LNF at the medial ankle, it should be entirely covered by an anteriorly-based local flap, and the donor site defect of the local flap can be treated with either pre-tie sutures or a skin graft.

Cutaneous perforators of the arm and anatomical landmarks for defining the flap donor sites.

PURPOSE: There are few studies searching for possible perforator flap donor sites on the arm. This study aimed to identify the locations of cutaneous perforators of the arm according to anatomical landmarks. METHODS: Thirteen Thiel-fixed and latex-filled upper extremities of bodies donated to science were used. The distance between the acromion and medial or lateral epicondyle of the humerus was defined as the Y-axis, and the axis that cut the Y-axis perpendicularly through the epicondyles of the humerus was identified as the X-axis. The Y-axis was then divided into three parts Cutaneous arterial perforators were found using surgical dissection. The locations of the perforators were determined according to the defined lines and regions. RESULTS: On the lateral side, there were 6.00 ± 2.08 perforators per arm, of which 56.4% were septocutaneous and 43.6% muscular. In all extremities, with in the distal 1/3 of the lateral arm, there were 1-4 radial collateral artery-based perforators. The mean distance of these perforators to the Y-axis was 1.16 ± 0.53 cm. On the medial side, there were 5.05 ± 1.44 perforators per arm, which were all septocutaneous perforators. In 85% of the extremities, within the middle 1/3 of the medial arms, there were 1-2 superior ulnar collateral artery-based perforators. The mean distance of these perforators to the Y-axis was 1.53 ± 0.61 cm. CONCLUSION: There are always perforators from the radial collateral artery with in the distal third of the lateral arm. Within the middle third of the medial arm, it is usually possible to find a perforator from the superior ulnar collateral artery.

Postmortem Interval Estimation With Corneal Endothelial Cell Density.

OBJECTIVES: In the neonatal period, healthy people have the highest corneal endothelial cell density (CECD) (5000-7000 cells/mm2). Corneal endothelial cell density declines with age in adults (2500-3000 cells/mm2) and continues to decline in the postmortem period. We measured CECD in cases with different postmortem interval (PMI) and investigated its association with PMI. METHODS: A total of 555 corneas harvested from 285 cases with a known time of death were examined using a specular microscope. RESULTS: Postmortem corneal removal time ranged between 10 and 1395 minutes. The CECD averages were 2653 for right cornea and 2678 cells/mm2 for left cornea. An inverse but nonlinear relationship was found between age and CECD. In both men and women, there was an inverse and weak correlation between age and CECD (ρ = -0.282; P < 0.001; ρ = -0.264; P < 0.001, respectively). There was no significant relationship between postmortem corneal removal time and CECD (ρ = 0.049; P = 0.421; ρ = 0.011; P = 0.855 for right and left corneas, respectively). The highest decline in time dependent CECD was detected between the 480th and 540th minutes at -7.2%. CONCLUSIONS: We found no significant decrease in CECD numbers according to PMI or cause of death. Experimental studies on cases with known and standardized antemortem CECD values will provide essential results in estimating PMI.

Evaluation of Increased Intracranial Pressure with the Optic Nerve Sheath Diameter by Ultrasound in Epiduroscopic Neural Laser Discectomy Procedures.

BACKGROUND: In order to clarify the camera image and open the adhesions mechanically during epiduroscopy, saline is injected continuously in the epidural area. As a result, an increase in intracranial pressure is to be expected in theory. Increased intracranial pressure can be evaluated by measuring by optic nerve sheath diameter. OBJECTIVES: This study was designed to evaluate the relationship between optic nerve sheath diameter measurements and intracranial pressure, after injecting fluid to the epidural area during epiduroscopy procedures performed in our clinic. STUDY DESIGN: Retrospective study. SETTING: Sakarya University Training and Research Hospital. METHODS: During the epiduroscopy procedure, pre and postoperative bilateral optic nerve sheath diameters were measured with an ultrasonography probe. With the patients' eyelids closed, the probe was placed on the orbita in the sagittal plane, measuring 3 mm posterior of the papilla. RESULTS: While there was a statistically significant difference between pre- and post-operative optic nerve sheath diameter measurements, there was no significant correlation with processing time, amount of fluid delivered, or fluid delivery rates. LIMITATIONS: One of the limitations of this study is the retrospective collection of data. A second limitation is that repetitive measurements were not performed, instead of a single postoperative measurement. CONCLUSION: We think more prospective randomized controlled studies are required to examine the increase in the diameter of the optic nerve sheath, which is an indirect indicator of increased intracranial pressure after epiduroscopy applications, in order to determine whether the pressure increase is associated with the rate of fluid delivery, the total fluid amount, or the processing time.

Neurological Outcomes of Normothermia versus Targeted Temperature Management in Post-cardiac Arrest Syndrome.

OBJECTIVE: To determine the neurological outcome of targeted temperature management (TTM)for patients scoring lower than 8 on the Glasgow coma scale (GCS) upon return of spontaneous circulation (ROSC) after cardiac arrest. STUDY DESIGN: Retrospective cohort study. PLACE AND DURATION OF STUDY: Department of Anaesthesiology and Reanimation, Sakarya University Education And Research Hospital, Sakarya, Turkey from January 2018 to October 2019. METHODOLOGY: Data of patients hospitalised in the AnaesthesiaIntensive Care unit for cardiac arrest receiving TTM and standard supportive therapy were analysed. Neurological outcome was evaluated with cerebral performance category (CPC) scores. Hospital stay and 30-day mortality was also noted. RESULTS: Data from 58 patients were analysed; 31 had received standard supportive therapy (non-TTM group) and 27 were treated with TTM (TTM group). There was no significant difference in hospital stay and patients' 30-day mortality between the two groups. The number of patients in the TTM group with CPC scores of 1 and 2, rated as a good neurological result, was significantly higher (n=11,40.7%) than in the non-TTM group (n=2, 6.5%;p=0.002). The number of patients with CPC scores of 3 and 4, rated as having a neurological disability,was higher in the non-TTM group (n = 9, 29%) than in the TTM group (n=1, 3.7%). CONCLUSION: Neurological results were better in the TTM group of patients with ROSC. However, there was no significant difference in mortality between the TTMand non-TTM groups. Key Words: Targeted temperature management, Cardiac arrest, Neurological outcome, Cerebral performance category.

The deep inferior epigastric lymphatic cable flap connected to gastroepiploic lymph node flap for treatment of refractory chylous ascites: Report of two cases.

Chylous ascites is the leakage of lipid-rich lymph into the peritoneal cavity usually due to disruption of lymphatics or increased peritoneal lymphatic pressure. Various surgical options have been proposed to treat chylous ascites but most have shown suboptimal outcomes. The gastroepiploic vascularized lymph node (GE-VLN) flap has been described previously for the treatment of lymphedema. In chylous ascites, this flap could provide an alternate drainage pathway for the intraperitoneal chylous fluid. The purpose of this report is to present another option for the microsurgical treatment of refractory chylous ascites. Herein, we report two patients with refractory chylous ascites secondary to cancer who have undergone deep inferior epigastric-based lymphatic "cable" flap (DIE-LCF) connected to a pedicle GE-VLN flap. Patients were followed-up for a minimum of 2 years. Within the first 3 months following surgery, the patient's nutritional parameters improved along with drastic reduction of ascites. At 2 years follow-up postoperative abdominal circumference decreased significantly. None required further peritoneal paracentesis and all patients were free of chylous ascites symptoms. In conclusion, the DIE-LCF connected to a pedicle GE-VLN flap could be a feasible option for the microsurgical treatment of refractory chylous ascites.

A rare giant sarcoma of the chest wall: Undifferentiated pleomorphic sarcoma.

Undifferentiated pleomorphic sarcoma or, as formerly called, malignant fibrous histiocytoma is a type of sarcoma which originates from fibroblast and histiocytic cells. It is the most common type of sarcoma among all soft tissue sarcomas in adults. Its most common site is the lower limb, followed by the upper limb and the retroperitoneum. It is rarely encountered on chest wall. In the differential diagnosis of masses on chest wall, it is important to consider undifferentiated pleomorphic sarcoma in surgical planning. In this article, we report a male case with a giant undifferentiated pleomorphic sarcoma located above the right scapula.

Evaluation of the COVID-19 Pandemic Intervention Strategies with Hesitant F-AHP.

In this study, a hesitant fuzzy AHP method is presented to help decision makers (DMs), especially policymakers, governors, and physicians, evaluate the importance of intervention strategy alternatives applied by various countries for the COVID-19 pandemic. In this research, a hesitant fuzzy multicriteria decision making (MCDM) method, hesitant fuzzy Analytic Hierarchy Process (hesitant F-AHP), is implemented to make pairwise comparison of COVID-19 country-level intervention strategies applied by various countries and determine relative importance scores. An illustrative study is presented where fifteen intervention strategies applied by various countries in the world during the COVID-19 pandemic are evaluated by seven physicians (a professor of infectious diseases and clinical microbiology, an infectious disease physician, a clinical microbiology physician, two internal medicine physicians, an anesthesiology and reanimation physician, and a family physician) in Turkey who act as DMs in the process.

Technical details for harvesting gastro-epiploic lymph node flaps via mini-laparotomy incision.

Laparoscopic harvest method to obtain gastro-epiploic lymph node flaps for lymphedema treatment has been previously described. In this article, the technical details of an alternative method - open approach via mini-laparotomy incision - for harvesting gastro-epiploic lymph node flaps and preparation of the flaps for the inset is presented. A total of 17 patients were included in this series of the mini-laparotomy approach. Blood loss was minimal during the surgery. The average duration of lymph node flap harvest was 65 min. The average length of hospital stay was 10 days. The period of the restricted diet was 1.5 days. The upper abdominal scar was acceptable, there were no postoperative hernia or bulging, and there were no complications related to bowel obstruction during the follow-up. The open approach harvest method via mini-laparotomy incision offers similar results to laparoscopic harvest method, and it is safe when applied with the right technique.

3D cellular alignment and biomimetic mechanical stimulation enhance human adipose-derived stem cell myogenesis.

Determination of a stem cell source with sufficient myogenic differentiation capacity that can be easily obtained in large quantities is of great importance in skeletal muscle regeneration therapies. Adipose-derived stem cells (ASCs) are readily available, can be isolated from fat tissue with high yield and possess myogenic differentiation capacity. Consequently, ASCs have high applicability in muscle regenerative therapies. However, a key challenge is their low differentiation efficiency. In this study, we have explored the potential of mimicking the natural microenvironment of the skeletal muscle tissue to enhance ASC myogenesis by inducing 3D cellular alignment and using dynamic biomimetic culture. ASCs were entrapped and 3D aligned in parallel within fibrin-based microfibers and subjected to uniaxial cyclic stretch. 3D cell alignment was shown to be necessary for achieving and maintaining the stiffness of the construct mimicking the natural tissue (12 ± 1 kPa), where acellular aligned fibers and cell-laden random fibers had stiffness values of 4 ± 1 and 5 ± 2 kPa, respectively, at the end of 21 d. The synergistic effect of 3D cell alignment and biomimetic dynamic culture was evaluated on cell proliferation, viability and the expression of muscle-specific markers (immunofluorescent staining for MyoD1, myogenin, desmin and myosin heavy chain). It was shown that the myogenic markers were only expressed on the aligned-dynamic culture samples on day 21 of dynamic culture. These results demonstrate that 3D skeletal muscle grafts can be developed using ASCs by mimicking the structural and physiological muscle microenvironment.

A Novel Combination Technique: Three Points of Epiduroscopic Laser Neural Decompression and Percutaneous Laser Disc Decompression With the Ho:YAG Laser in an MSU Classification 3AB Herniated Disc.

AIM: The aim of this study was to examine the effects of simultaneous epiduroscopic laser neural disc decompression (ELND) and percutaneous laser disc decompression (PLDD) applications using a holmium:yttrium-aluminum-garnet (Ho:YAG) laser in Michigan State University (MSU) classification 3AB herniated discs on VAS and Oswestry Disability Index (ODI) scores. METHODS: In this prospective observational study, ELND and PLDD procedures performed between January 2016 and December 2017 were examined. Preoperative, postoperative week 2, postoperative month 2, and postoperative month 6 ODI and VAS scores were obtained from patient files, and postoperative month 12 ODI and VAS scores were obtained from face-to-face interviews with patients and recorded. RESULTS: The data of 41 patients treated with simultaneous ELND and PLDD using a Ho:YAG laser were included in this study. Postoperative VAS scores of the patients were compared with preoperative values, and it was found that postoperative week 2, postoperative month 2, postoperative month 6, and postoperative month 12 VAS and ODI scores were significantly different compared to preoperative scores (P = 0.001; P < 0.01). 17.1% (n = 7) of the patients had a history of postoperative open surgery. Although dural puncture occurred in 7 patients (17%), only 1 patient had headache. CONCLUSION: We believe that the new combined technique of ELND and PLDD using a Ho:YAG laser is a reliable method in patients with MSU classification 3AB herniated discs, with an acceptable success rate and a low complication rate within 12 months after treatment. We think that randomized controlled studies are required for this method to be included in treatment algorithms.

Immediate emergency free anterolateral thigh flap after car-tyre friction injury: A case report with eight years follow-up.

The car-tyre friction injury has differences from other injuries. The components of injury which are burn, crushing, shearing, and degloving occur. Many treatment options can be performed for coverage of wound which are Vacuum Assisted Closure system (V.A.C), skin grafting, free flaps, local flaps and cross leg flap.