31 research outputs found
Biological Optimization of Cortical Bone Allografts: A Study on the Effects of Mesenchymal Stem Cells and Partial Demineralization and Laser Perforation
Background: Despite promising results have shown by osteogenic cell-based demineralized bone matrix composites, they need to be optimized for grafts that act as structural frameworks in load-bearing defects. The purpose of this experiment is to determine the effect of bone marrow mesenchymal stem cells seeding on partially demineralized laser-perforated (DLP) structural allografts that have been implanted in critical femoral defects.Methods: Thirty-two Wistar rats were divided into four groups according to the type of structural bone allograft; the first: partially demineralized only (Donly), the second: partially demineralized stem cell seeded (DST), the third: partially DLP, and the fourth: partially demineralized laser-perforated and stem cell seeded (DLPST). Trans-cortical holes were achieved in four rows of three holes approximated cylindrical holes 0.5 mm in diameter, with centers 2.5 mm apart. P3 mesenchymal stromal cells (MSCs) were used for graft seeding. Histologic and histomorphometric analysis was performed at 12 weeks.Results: DLP grafts had the highest woven bone formation, where most parts of laser pores were completely healed by woven bone. DST and DLPST grafts surfaces had extra vessel-ingrowth-like porosities. Furthermore, in the DLPST grafts, a distinct bone formation at the interfaces was noted.Conclusions:This study indicated that surface changes induced by laser perforation, accelerated angiogenesis induction by MSCs, which resulted in endochondral bone formation at the interface. Despite non-optimal results, stem cells showed a tendency to improve osteochondrogenesis, and the process might have improved if they could have been supplemented with the proper stipulations
Speleotherapy as an Effective Treatment of Chronic Obstructive Pulmonary Disease
Abstract
Objectives: Chronic obstructive pulmonary disease (COPD) as a liberal illness requires constant
anti-inflammatory therapy. As praise of conventional treatments, patients ofen turn to alternate
therapy. Current study aimed to evaluate the frst study in Iran emphasizing on halotherapy
influence on improving lung function testing results and relieving symptoms of Chronic Obstructive
Pulmonary Disease patients, presented at respiratory referral hospital, Tehran in 2016.
Materials and Methods: In this double-blind clinical study, 84 components suffering from COPD
detached to two experimental and control groups. Following two months treatment with salitair
or placebo, one month clearance phase was carried. Eventually, groups were treated with salitair
and placebo for next two months. Influence was determined assessed6-minute walk distant, arterial
oxygen saturation drop of six minutes walking, CAT enquiry and spirometry FEV1, FVC and FEV1/
FVC parameters.
Results: Current study revealed that halotherapy might exert a positive effect on 6-minute walk
distant and arterial oxygen saturation drop of six minutes walking parameters, since has no effect
on CAT enquiry and FEV1, FVC and FEV1/FVC parameters.
Conclusions: Advice for containing halotherapy as a healing treatment for COPD is doubtful. More
studies are recommended to be done, including a larger study group to supply the best evidence.
Keywords: Chronic obstructive pulmonary disease (C08.381.495.389); Spirometry
(E01.370.386.700.750); Vaporizers (E07.605); Halotherapy; Spleotherapy; Salitai
Cardiopulmonary Exercise Test in Advanced Heart Failure Among Heart Transplantation Candidates
Cardiopulmonary exercise test has been raised through recent decades as a brilliant prognostic tool in a wide field of diseases and clinical conditions which makes it valuable to be used in prognostic assessment during the current study among chronic heart failure (CHF) patients. This study recruited 71 patients with severe CHF who were candidates for heart transplantation. Bicycle-protocol Cardiopulmonary Exercise Test was done, and several parameters were measured and compared between four groups of patients based on their VO2/kg to show four grades of the disease from G1 to G4. Total 71 CHF subjects from 18 to 46 year of age enrolled in the study. Statistically significant correlations were determined between HRR, VE/VCO2, VE/VO2, BR and the severity of CHF. VO2max, HRR, VE/VO2, VE/VCO2, BR, and AT were the most prominent factors of CPET which showed their validity and reliability in terms of prognosis of CHF. It seems that combination of CPET and other cardiac prognostic tools like echocardiography and measurement of the pressure in cardiac chambers can improve the prognosis in CHF
Geographic wormhole detection in wireless sensor networks.
Wireless sensor networks (WSNs) are ubiquitous and pervasive, and therefore; highly susceptible to a number of security attacks. Denial of Service (DoS) attack is considered the most dominant and a major threat to WSNs. Moreover, the wormhole attack represents one of the potential forms of the Denial of Service (DoS) attack. Besides, crafting the wormhole attack is comparatively simple; though, its detection is nontrivial. On the contrary, the extant wormhole defense methods need both specialized hardware and strong assumptions to defend against static and dynamic wormhole attack. The ensuing paper introduces a novel scheme to detect wormhole attacks in a geographic routing protocol (DWGRP). The main contribution of this paper is to detect malicious nodes and select the best and the most reliable neighbors based on pairwise key pre-distribution technique and the beacon packet. Moreover, this novel technique is not subject to any specific assumption, requirement, or specialized hardware, such as a precise synchronized clock. The proposed detection method is validated by comparisons with several related techniques in the literature, such as Received Signal Strength (RSS), Authentication of Nodes Scheme (ANS), Wormhole Detection uses Hound Packet (WHOP), and Wormhole Detection with Neighborhood Information (WDI) using the NS-2 simulator. The analysis of the simulations shows promising results with low False Detection Rate (FDR) in the geographic routing protocols
Umbilical Cord Blood Platelet Lysate as Serum Substitute in Expansion of Human Mesenchymal Stem Cells
Objective: The diverse clinical applications for human mesenchymal stem cells (hMSCs)
in cellular therapy and regenerative medicine warrant increased focus on developing
adequate culture supplements devoid of animal-derived products. In the
present study, we have investigated the feasibility of umbilical cord blood-platelet
lysate (UCB-PL) as a standard substitute for fetal bovine serum (FBS) and human
peripheral blood-PL (PB-PL).
Materials and Methods: In this experimental study, platelet concentrates (PC) from UCB
and human PB donors were frozen, melted, and sterilized to obtain PL. Quality control
included platelet cell counts, sterility testing (viral and microbial), total protein concentrations,
growth factor levels, and PL stability. The effects of UCB-PL and PB-PL on hMSCs
proliferation and differentiation into osteocytes, chondrocytes, and adipocytes were studied
and the results compared with FBS.
Results: UCB-PL contained high levels of protein content, platelet-derived growth factor-
AB (PDGF-AB), and transforming growth factor (TGF) compared to PB-PL. All growth
factors were stable for at least nine months post-storage at -70ËšC. hMSCs proliferation
enhanced following treatment with UCB-PL. With all three supplements, hMSCs could
differentiate into all three lineages.
Conclusion: PB-PL and UCB-PL both were potent in hMSCs proliferation. However, PB
promoted osteoblastic differentiation and UCB-PL induced chondrogenic differentiation.
Because of availability, ease of use and feasible standardization of UCB-PL, we have suggested
that UCB-PL be used as an alternative to FBS and PB-PL for the cultivation and
expansion of hMSCs in cellular therapy
Are There Any Epigenetic Similarities Between Treatment Unresponsive Sarcoidosis, COPD and Severe Asthma?
 No Abstrac
Classification of Asthma Based on Nonlinear Analysis of Breathing Pattern.
Normal human breathing exhibits complex variability in both respiratory rhythm and volume. Analyzing such nonlinear fluctuations may provide clinically relevant information in patients with complex illnesses such as asthma. We compared the cycle-by-cycle fluctuations of inter-breath interval (IBI) and lung volume (LV) among healthy volunteers and patients with various types of asthma. Continuous respiratory datasets were collected from forty age-matched men including 10 healthy volunteers, 10 patients with controlled atopic asthma, 10 patients with uncontrolled atopic asthma, and 10 patients with uncontrolled non-atopic asthma during 60 min spontaneous breathing. Complexity of breathing pattern was quantified by calculating detrended fluctuation analysis, largest Lyapunov exponents, sample entropy, and cross-sample entropy. The IBI as well as LV fluctuations showed decreased long-range correlation, increased regularity and reduced sensitivity to initial conditions in patients with asthma, particularly in uncontrolled state. Our results also showed a strong synchronization between the IBI and LV in patients with uncontrolled asthma. Receiver operating characteristic (ROC) curve analysis showed that nonlinear analysis of breathing pattern has a diagnostic value in asthma and can be used in differentiating uncontrolled from controlled and non-atopic from atopic asthma. We suggest that complexity analysis of breathing dynamics may represent a novel physiologic marker to facilitate diagnosis and management of patients with asthma. However, future studies are needed to increase the validity of the study and to improve these novel methods for better patient management
Wormhole attack in geographical routing protocols, (a) static wormhole, (b) dynamic wormhole.
<p>Wormhole attack in geographical routing protocols, (a) static wormhole, (b) dynamic wormhole.</p