FDTD simulations to assess the performance of CFMA-434 applicators for superficial hyperthermia

Introduction: Contact flexible microstrip applicators (CFMA), operating at 434 MHz, are applied at the Academic Medical Center (AMC) for superficial hyperthermia (e.g. chest wall recurrences and melanoma). This paper investigates the performance of CFMA, evaluating the stability of the specific absorption rate (SAR) distribution, effective heating depth (EHD) and effective field size (EFS) under different conditions.

Methods: Simulations were performed using finite differences and were compared to existing measurement data, performed using a rectangular phantom with a superficial fat-equivalent layer of 1 cm and filled with saline solution. The electrode plates of the applicators measure ～7 × 20, 29 × 21 and 20 × 29 cm². Bolus thickness varied between 1 and 2 cm. The impact of the presence of possible air layers between the rubber frame and the electrodes on the SAR distribution was investigated.

Results: The EHD was ～1.4 cm and the EFS ranged between ～60 and ～300 cm², depending on the applicator type. Both measurements and simulations showed a split-up of the SAR focus with a 2 cm water bolus. The extent and location of air layers has a strong influence on the shape and size of the iso-SAR contours with a value higher than 50%, but the impact on EFS and EHD is limited.

Conclusion: Simulations, confirmed by measurements, showed that the presence of air between the rubber and the electrodes changes the iso-SAR contours, but the impact on the EFS and EHD is limited.     

Platelet activation, inflammatory mediators and hypercholesterolemia

Atherogenic cofactors, such as altered cholesterol metabolism, may impact locally on inflammatory responses in atherosclerotic lesions. Blood levels of inflammatory markers (e.g., C-reactive protein, fibrinogen) have been associated with hypercholesterolemia and with overt atherothrombotic disorders. More recently. cytokines (e.g., interleukin-6, interleukin-1beta) and soluble adhesion molecules (e.g., selectins, intercellular adhesion molecule-1, vascular cell adhesion molecule-1) have been associated with both hypercholesterolemia and atherosclerotic disease, suggesting their use as potential therapeutic targets for the non-specific "anti-inflammatory" treatment of atherosclerosis. The inflammatory response associated with hypercholesterolemia involves not only the intrinsic cells of the artery wall. but also circulating cells. Platelets participate in this disease process through the release of a wide variety of biologically active substances. An imbalance of the hemostatic system and persistent in vivo platelet activation can be observed in hypercholesterolemia and may have pathophysiological implications in the development and progression of atherosclerotic plaques. Recent findings on the inflammatory actions of platelets have established the potential for a previously unrecognized biologic role for platelets in inflammation and vascular injury, and have opened new perspectives in the comprehension of the pathogenetic mechanism(s) of atherosclerosis. Stimulated platelets actively synthesize proinflammatory cytokines (e.g., CD40L, IL-1beta) and are able to release chemokines (i.e., platelet factor-4, RANTES) which have been all involved in the inflammatory process associated with hypercholesterolemia. This review will summarize the present understanding of the interplay between hypercholesterolemia, inflammation and platelet activation in the development and progression of atherosclerosis, and we also discuss the effects of lipid-lowering treatment on these phenomena.     

冠心病血瘀证的Gensini积分与血管内皮因子的关系

目的：探讨冠心病血瘀证Gensini积分与血管内皮因子的关系。方法：将96例冠心病血瘀证患者辨证分为气虚血瘀证和痰瘀互阻证各48例,进行冠脉造影及血管内皮因子的测定,同时采用血瘀证积分评定血瘀证程度,采用Gensini评分系统评价冠脉造影的结果。结果：气虚血瘀证血瘀证积分及冠状动脉狭窄程度高于痰瘀互阻证;血清VEGF、ET-1水平随血瘀证积分及Gensini积分增高而增高;IGF-1水平随血瘀证积分及Gensini积分增高而降低。结论：冠脉Gensini积分与血管内皮因子及血瘀证积分相关。     

Cyclooxygenase-2 contributes to functional changes seen on experimental hemorrhagic cystitis induced by ifosfamide in rat urinary bladder

Purpose

Ifosfamide (IFS) is often involved in the occurrence of hemorrhagic cystitis due to direct contact of its metabolite acrolein with uroepithelium. It has been shown that COX-2 is involved in this pathogenesis. Thus, we aimed to study the functional changes on the urinary bladder in the putative modifications induced by IFS, as well as the COX-2 role in this process.

Materials and methods

IFS-treated rats were evaluated by cystometrography in absence or presence of COX inhibitors indomethacin or etoricoxib or in the presence of mesna. Experiments with isolated strips of urinary bladder obtained from animals with IFS-induced cystitis, either treated or not treated with COX inhibitors or mesna, were performed. Histological analyses, immunohistochemistry for COX-2, and measurement of plasma PGE₂ were also performed.

Results

IFS treatment caused severe inflammation of the bladder tissue. Cystometrography recordings of IFS-treated rats revealed bladder with increased micturition frequency and enhanced filling intravesical pressure. Contractility of the isolated smooth muscle from the rat’s bladder with IFS-induced cystitis showed decreased force development in response to KCl and CCh. Almost all effects induced by IFS were ameliorated by the use of COX inhibitors or mesna. Enzyme expression in the urinary bladder tissue was positive, and plasma concentration of PGE₂ was increased in IFS-treated animals and decreased significantly in etoricoxib-treated animals.

Conclusions

IFS causes important changes in the micturition physiology in rats, and the inhibition of the isoenzyme COX-2 could be an important event that could prevent the detrimental effects elicited by IFS-induced hemorrhagic cystitis.     

Repair of critical-size defects with autogenous periosteum-derived cells combined with bovine anorganic apatite/collagen: an experimental study in rat calvaria

The aim of this study was to evaluate the bone repair using autogenous periosteum-derived cells (PDC) and bovine anorganic apatite and collagen (HA-COL). PDC from Wistar rats (n=10) were seeded on HA-COL discs and subjected to osteoinduction during 6 days. Critical-size defects in rat calvarias were treated with blood clot (G1), autogenous bone (G2), HA-COL (G3) and HA-COL combined with PDC (G4) (n=40), and then analyzed 1 and 3 months after surgeries. Radiographic analysis exhibited no significant temporal change. G1 and G2 had discrete new marginal bone, but the radiopacity of graft materials in G2, G3 and G4 impaired the detection of osteogenesis. At 3 months, histopathological analysis showed the presence of ossification islets in G1, which was more evident in G2, homogeneous new bone around HA-COL in G3 and heterogeneous new bone around HA-COL in G4 in addition to moderate presence of foreign body cells in G3 and G4. Histomorphometric analysis showed no change in the volume density of xenograft (p>0.05) and bone volume density in G2 was twice greater than in G1 and G4 after 3 months (p<0.05), but similar to G3. The PDC did not increase bone formation in vivo, although the biomaterial alone showed biocompatibility and osteoconduction capacity.     

Water extracts of Brazilian leguminous seeds as rich sources of larvicidal compounds against Aedes aegypti L

This study assessed the toxicity of seed water extracts of 15 leguminous species upon Aedes aegypti larvae. A partial chemical and biochemical characterization of water extracts, as well as the assessment of their acute toxicity in mice, were performed. The extracts of Amburana cearensis, Anadenanthera macrocarpa, Dioclea megacarpa, Enterolobium contortisiliquum and Piptadenia moniliformis caused 100% of mortalit y after 1 to 3 h of exposure. They showed LC(50) and LC(90) values ranging from 0.43 ± 0.01 to 9.06 ± 0.12 mg/mL and from 0.71 ± 0.02 to 13.03 ± 0.15 mg/mL, respectively. Among the secondary metabolite constituents, the seed water extracts showed tannins, phenols, flavones, favonols, xanthones, saponins and alkaloids. The extracts also showed high soluble proteins content (0.98 to 7.71 mg/mL), lectin (32 to 256 HU/mL) and trypsin inhibitory activity (3.64 = 0.43 to 26.19 = 0.05 gIT/kg of flour) The electrophoretic profiles showed a great diversity of protein bands, many of which already described as insecticide proteins. The extracts showed low toxicity to mice (LD(50) > 0.15 = 0.01 g/kg body weight), but despite these promising results, further studies are necessary to understand the toxicity of these extracts and their constituents from primary and secondary metabolism upon Ae. aegypti.     

Detection of periodontal pathogens in oral mucous membranes of edentulous individuals

BACKGROUND: The purpose of this study was to investigate the colonization of Campylobacter rectus, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Prevotella intermedia, and Tannerella forsythia (previously T. forsythensis) in the tongue and cheek of newborns and elderly individuals with no teeth. METHODS: Seventy-four edentulous subjects were included in this cross-sectional study. Microbiologic samples were taken from the dorsum of the tongue and cheek mucosa of all individuals and analyzed using a bacterial DNA-specific polymerase chain reaction. RESULTS: C. rectus was the most prevalent species in both groups (20.9% in the cheek of newborns, and 77.4% in the tongue of elderly subjects). P. gingivalis and P. intermedia were not detected in any of the 43 newborns; however, P. gingivalis was recovered from the tongue and cheek (3.2%) of elderly individuals, whereas P. intermedia was detected in the tongue (9.6%) and cheek (3.2%) of elderly individuals. T. forsythia was detected in newborns as well as elderly individuals, although the highest prevalence was observed in the tongue of newborns (6.9%) and elderly (9.6%) individuals. A. actinomycetemcomitans was not found in the tongue of newborns, but we observed A. actinomycetemcomitans in the cheek (2.3%) of newborns and in the tongue (12.9%) and cheek (6.4%) of elderly patients. CONCLUSIONS: Although we did not detect P. gingivalis and P. intermedia in newborns, periodontal pathogens could be detected from the oral mucous membranes of edentulous individuals. Our results suggest that major attention should be paid to edentulous individuals as an important measure in the prevention of the initial colonization of natural teeth and dental implants by periodontal pathogens.     

No association between periodontitis and preterm low birth weight: a case–control study

Purpose

This study aimed to investigate the association between periodontitis in pregnant women and adverse pregnancy outcomes by heeding confounding risk factors for preterm low birth weight infants.

Methods

This study was reported according to The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement. A case–control study was conducted. Medical records of all pregnant women attending a prenatal care clinic were screened. Those between 21 and 34 years and gestational age of 28–32 weeks were initially enrolled in the study. The exclusion criteria were then applied: diabetes mellitus, genitourinary tract infections, or HIV infection; previous multiple gestations; previous preterm birth/low birth weight infants; in vitro fertilization procedures; placental, cervical/uterine abnormalities; history of infertility; history of drug abuse; and any medical conditions that required antibiotics prophylaxis. Patients’ anthropometric, demographic, and behavioral characteristics were collected. The periodontal clinical parameters were obtained from six sites per tooth: clinical attachment level, probing pocket depth, dental plaque index, and gingival bleeding index. Women were then allocated into two groups: mothers of preterm and/or low birth weight newborns (cases) and mothers of full-term and normal birth weight newborns (controls).

Results

Periodontal clinical parameters were analyzed and reported separately for each group, and no significant differences were observed (p > 0.05). Logistic regression analysis revealed that periodontal clinical parameters were not associated with the adverse pregnancy outcomes.

Conclusion(s)

After controlling for confounding factors, our results suggest that maternal periodontal disease is not a risk factor associated with preterm low birth weight infants.

     

Gestational exposure to Byrsonima verbascifolia: Teratogenicity,mutagenicity and immunomodulation evaluation in female Swiss mice

Ethnopharmacological relevance

Byrsonima verbascifolia is used in folk medicine to treat diarrhea, intestinal infections, chronic wounds, Chagas disease, inflammation and as a diuretic. However there is no investigation regarding the Byrsonima verbascifolia hydrometanolic extract (BVHME) used during gestation.

Materials and methods

The pregnant females were randomly divided into 5 groups. Control group received saline plus DMSO (1%) in a volume of 0.1 mL/10 g (b.w.), via gavage, for at least 15 days prior to mating and throughout the gestational period. The Pre-treatment group received the BVHME, via gavage, at a dose of 50 mg/kg (b.w.) for at least 15 days prior to mating and up to the appearance of the vaginal plug. The Organogenesis group received the BVHME at a dose of 50 mg/kg (b.w.), via gavage, on the 5–15th gestational day. The Gestational group received the BVHME at a dose of 50 mg/kg (b.w.), via gavage, throughout the gestational period (from the 1st to the 18th day of pregnancy). The Pre+Gestational group received the BVHME at a dose of 50 mg/kg (b.w.), via gavage, for at least 15 days prior to mating and up to throughout the gestational period. The clinical signals of maternal and fetuses toxicity were evaluated, as the mutagenicity and immunomodulation tests were performed.

Results and conclusions

The present investigation shows, for the first time, that the use of Byrsonima verbascifolia extract in pregnant Swiss mice, did not alter the female reproductive function, mutagenicity or immunostimulation as well as not interfere with embryofetal development at least in our experimental conditions.