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Fermented Spirulina platensis(FS) has recently attained attraction in human food due to its high functionality and rich content of bioactive compounds. Therefore, the current study investigated the potential roles of dietary FS on the growth performance, digestion capacity, antioxidative status, and immune response of Nile tilapia. Dietary FS at 0, 0.5, 1, 2, 4, and 8 g/kg were fed to Nile tilapia for 60 days. All formulated diets were isonitrogenous and isocaloric with 30.48 % crude protein and 6.63 % total lipids, respectively. The results indicated that the final weight (FW, P=0.004), weight gain (P=0.023), and specific growth rate (SGR, P=0.021) were influenced by dietary FS in a significant quadratic manner. Accordingly, the regression analysis revealed that the suggested doses of FS supplementation in Nile tilapia diets to show the highest FW and SGR are 4.26 and 3.98 g/kg, respectively. Furthermore, dietary FS enhanced the amylase (P=0.035) and lipase (P=0.004) activities in a quadratic manner. The elevated doses of dietary FS instigated prominent improvement of the villous height and goblet cell and increased branching of intestinal villi in the middle segments, particularly in fish fed 4 and 8 g/kg. The red blood cells (P=0.009), hemoglobulin (P=0.004), hematocrit (P=0.034), and white blood cells (P=0.014) were increased significantly with dietary FS in a quadratic manner. No marked effects were seen on the alanine transaminase, aspartate aminotransferase, urea, creatinine, total cholesterol, and triglycerides. Meanwhile, the total protein (P=0.039), albumin (P=0.021), and globulin (P=0.002) were increased significantly by dietary FS in a quadratic manner. The superoxide dismutase (P=0.005) and catalase (P=0.022) were increased, while malondialdehyde level (P=0.028) was decreased significantly with dietary FS in a quadratic manner. The lysozyme activity was higher in fish-fed FS at 0.5, 1, 2, 4, and 8 g/kg than in fish-fed FS at 0 g/kg. The phagocytic activity was higher in fish-fed FS at 2 and 4 g/kg than in fish-fed FS at 0, 0.5, and 8 g/kg without significant differences with fish-fed FS at 1 g/kg (P˃0.05). The regression analysis revealed that the suggested doses of FS supplementation in Nile tilapia diets to show the highest lysozyme activity and catalase activity are 3.52 and 3.79 g/kg, respectively. In conclusion, dietary FS enhanced growth performance, feed utilization, digestive enzyme activity, blood health, immunity, and antioxidative response. Overall, dietary FS can be added at 3.52–4.26 g/kg to enhance the productivity and well-being of Nile tilapia.

The porosity exponent m represents an important parameter in Archie's equation; it is routinely used in well logging interpretation and formation evaluation. It reflects some petrophysical rock properties, such as the petrofabrics, pore fabrics, and overburden pressure (OBP). Data measured at ambient conditions for a total of 55 sandstone core samples were obtained from 8 wells varying in depositional facies, geologic age, degree of consolidation, and cementation material and then measured again at OBP, similar to the actual reservoir conditions, to check the effect of OBP on Archie's parameters and to introduce a model of high reliability. Other published data sets were also used to confirm the study results. Based on the best-fit regression analysis, several empirical relationships were introduced to relate the porosity exponent to pore volume, lithology factor, and permeability. The effect of OBP on the porosity exponent was also investigated in relation to the petrophysical parameters. Given the above, a new statistical model is proposed to relate the porosity exponent to the permeability of the studied sandstone samples in the Gulf of Suez, Egypt. The effect of confining pressure on the studied porosity exponent m and the lithology factor a is significant when porosity ϕ is less than or equal to 10%. From the present study, categorization of the studied samples into flow units and rock types using the hydraulic flow unit and the discrete rock types increased the reliability of the obtained relationships and increased the applicability of the obtained equations. In addition, the value of the lithology factor a fluctuates around 1 (0.92-1.04, regardless of the applied processing method), whereas the value of the porosity exponent m fluctuates around 1.83. The obtained relationships between the formation resistivity factor and porosity have a very high reliability (-0.949 ≤ correlation coefficient ≤ -0.969). [ABSTRACT FROM AUTHOR]

The ability of recombinant human bone morphogenetic protein 2 on absorbable collagen sponge (rhBMP2/ACS) to regenerate bone in segmental defect has been well characterized. However, clinical results of rhBMP2/ACS constructs in secondary reconstruction of large mandibular and craniofacial defects have not been consistent. We hypothesized that rhBMP2delivery triggers an endogenous response in the soft tissues surrounding the defect, in the form of expression of BMP2and vascular endothelial growth factor (VEGF). Such osteogenic response will occur only after immediate, as opposed to delayed, rhBMP2delivery, suggesting a new explanation to the difference in bone regeneration between the two settings. A 35-mm segmental bone and periosteum defect was created on one side of the mandible in 16 dogs divided in three groups. Group 1 (Gp1, n=6) ACS was loaded with 8 mL of rhBMP2(0.2 mg/mL). In Gp2 (n=5) the same dose of rhBMP2/ACS was delivered into the defect 4 weeks after surgery. In Gp3 (control; n=5) the defect was reconstructed using ACS loaded with 8 mL of buffer only (devoid of rhBMP2). Tissues were collected after 12 weeks of reconstruction in all groups. Direct measurement of physical dimensions of regenerates and bone morphometry was performed to evaluate bone regeneration. The mRNA expression of both BMP2and VEGFin the soft tissue surrounding the defect was evaluated using real-time quantitative PCR. Both BMP2and VEGFproteins were quantified in immunostained sections. Immunoflurescence colocalization of BMP2and acetylated low density lipoprotein (AcLDL) was done to detect the source of BMP2. Immediate delivery yielded better bone regeneration. Both BMP2and VEGFmRNA expression was upregulated only in Gp1 (+7.3, p=0.001; +1.53, p=0.001, respectively). BMP2protein was significantly higher in the immediate reconstruction group; however, VEGFprotein was undetected in the examined sections. Immediate delivery of rhBMP2seemed to induce endogenous release of BMP2from the surrounding soft tissues, an effect that was lacking in delayed delivery and may explain the variability of clinical results associated with BMP2use. Colocalization of BMP2and endothelial cells (ECs) suggested that ECs could be the source of endogenous BMP2.

Diabetic patients with foot ulcers usually manifest with complications. Preliminary evidence supported the effectiveness of stem cell therapy on diabetic foot ulcers. Therefore, the objective of this study was to evaluate the efficacy of stem cells in the healing of experimentally induced wounds in diabetic albino rats.

Background:In healthy periodontal tissue, innate immune responses effectively confine and suppress a bacterial insult. However, a disruption of the host–bacterial equilibrium may produce an overexpression of cytokines and lead to permanent, host‐mediated tissue damage. Although such periodontal destruction primarily results from activated immune mechanisms, the site‐specific damage suggests that local tissues participate in these pathologic changes. Periodontal ligament fibroblasts (PDLFs) are prominent in the periodontium and are critical in homeostasis and regeneration because they have the ability to produce multiple cytokines in response to a bacterial insult. These cells could play a role in the local pathogenesis of periodontal disease. Methods:We studied alkaline phosphatase (ALP) activity, interleukin (IL)‐6 production, and morphologic characteristics of cultured PDLFs that were isolated from periodontally healthy sites (H‐PDLFs) and diseased sites (D‐PDLFs) in humans. Quantitative analyses of 84 genes that are related to inflammation were performed using real‐time polymerase chain reaction arrays. Results:A mineralizing medium induced a significant increase of ALP in H‐PDLFs, but no significant enzymatic changes were detected in D‐PDLFs after such treatment. The protein and gene expression of IL6showed a significant upregulation in D‐PDLFs, which also demonstrated a significant upregulation of 54% of genes in the inflammatory gene arrays. Conclusions:To our knowledge, these results represent the first biologic evidence that D‐PDLFs retain uniquely inflammatory phenotypes that could maintain localized destructive signals in periodontitis. The overexpression of proinflammatory cytokines by PDLFs could amplify local inflammation by the continuous triggering of immune responses. In addition, the location of these cells could be critical in the progression of the inflammatory front into the deeper tissues.

Background:Demineralized freeze‐dried bone (DFDB) is commonly hydrated with sterile water into a paste‐like consistency for improved clinical handling or reconstituted with biodegradable barriers, such as glycerol, to promote handling and wound stability following human periodontal surgery. The purpose of this study was to evaluate the in vivo effects of glycerol‐compounded human DFDB on bone formation in the rat calvarial critical‐sized defect (CSD) model. Methods:Forty‐eight adult male Harland Sprague‐Dawley rats were assigned to one of four treatment groups: glycerol, DFDB, DFDB plus glycerol, or a non‐grafted control, and placed into 8 mm calvarial CSDs. DFDB (particle size 0.106 to 0.5 mm), glycerol, and their combination were from identical sources. Calvaria were harvested at 8 weeks postsurgery and evaluated histomorphometrically. Results:A statistically significant increased percentage of total bone fill was detected in the glycerol plus DFDB group and DFDB group as compared to glycerol group or the control. However, no significant difference was noted between the DFDB plus glycerol group and the DFDB group. Conclusion:The addition of glycerol to DFDB results in comparable osseous regeneration in the rat calvarium defect model versus DFDB alone; however, based upon clinical judgment, handling characteristics of DFDB were greatly improved. J Periodontol 2003;74:1641‐1646.

Plant-derived phenolic compounds, including polyphenols (e.g., tannins), flavonoids, and phenolic acids, have been under investigation for their anticancer therapeutic and chemoprevention properties. Recently, certain mechanisms underlying the differential effects of green tea polyphenols (GTPPs) on tumor versus normal cells have been determined. These suggest that GTPPs may simultaneously activate multiple pathways. However, existing screening methods are insufficient for the identification of agents that possess both a cytotoxic effect on tumor cells and a protective effect on normal cells. The current study describes the establishment of an in vitrosurvival/apoptosis testing system based on detecting these mechanisms by a double-fluorescence method. This system is able to screen potential chemopreventive or therapeutic agents from (but not limited to) plant-derived compounds based on the pathways differentially activated by the agents. Tumor cell death and normal cell survival are detected simultaneously, in a device that co-cultures normal human cells adjacent to human tumor cells.

The most abundant green tea polyphenol, epigallocatechin-3-gallate (EGCG), was found to induce differential effects between tumor cells and normal cells. Nevertheless, how normal epithelial cells respond to the polyphenol at concentrations for which tumor cells undergo apoptosis is undefined. The current study tested exponentially growing and aged primary human epidermal keratinocytes in response to EGCG or a mixture of the four major green tea polyphenols. EGCG elicited cell differentiation with associated induction of p57/KIP2 within 24 h in growing keratinocytes, measured by the expression of keratin 1, filaggrin, and transglutaminase activity. Aged keratinocytes, which exhibited low basal cellular activities after culturing in growth medium for up to 25 days, renewed DNA synthesis and activated succinate dehydrogenase up to 37-fold upon exposure to either EGCG or the polyphenols. These results suggest that tea polyphenols may be used for treatment of wounds or certain skin conditions characterized by altered cellular activities or metabolism.

ABSTRACTThe purpose of the present study was to identify proliferating cells in control versus experimental condyles two weeks following experimental Induction of anterior disk displacement (ADD) in the rabbit craniomandibular joint (CMJ). The right joint of 15 rabbits was exposed surgically and all diskal attachments were severed except for the posterior attachment. The disk was then repositioned anteriorly and sutured to the zygomatic arch. The left joint served as a sham-operated control. Ten additional joints were used as nonoperated controls. Mandibular condyles were excised two weeks following surgery and processed for proliferating cell nuclear antigen (PCNA) immunostaining. In control and sham operated condyles, PCNA was localized in the nuclei of chondroblasts of the reserve cell layer, chondrocytes of the upper hypertrophic layer and bone marrow cells of the subchondral bone. In contrast to control joints, the PCNA positive cells of the experimental joints were located throughout the osteoarthritic condylar cartilage. In addition, the percentage of PCNA positive cells of the osteoarthritic condylar cartilage was statistically significantly higher when compared to the control group, p < 0.05. It was concluded that surgical induction of ADD in the rabbit CMJ leads to an increase in mitosis of chondrocytes, which lead to cell proliferation and subsequent hyperplasia of the condylar cartilage.

Background:Pluronic polyols are a family of non‐ionic surfactants currently used as drug carriers for antibiotic, anti‐inflammatory, and anti‐neoplastic agents. Therapeutic administration of non‐ionic surface‐active agents is known to facilitate early collagen synthesis and microcirculation, thus promoting wound healing. The purpose of this study was to determine the in vivo effects of pluronic polyols combined with either an allograft or an alloplast on the healing of critical‐sized calvarial defects. Methods:One hundred fifty (150) adult (95 to 105 days old) male Sprague‐Dawley rats weighing between 375 and 425 g were randomly and evenly assigned to each of 15 separate treatment groups and anesthetized, and 8 mm calvarial critical‐sized defects were created. Pluronic F‐68 (F‐68) or pluronic F‐127 (F‐127) was administered either topically or systemically and in conjuction with demineralized bone powder (DBP), tricalcium phosphate (TCP), or non‐grafted controls. Pluronic polyols are easily mixed with either DBP or TCP to improve handling ease. Calvaria were harvested at 12 weeks postsurgery and evaluated histomorphometrically, by contact radiography with subsequent densitometric analysis, through energy spectrometry utilizing a scanning electron microscope, and by fluorescent microscopy. Results:There was a significant difference in the percentage of bone fill among the control, TCP, and DBP only groups, P<0.05. The only significant difference within any of these groups was between the TCP control and TCP plus systemic F‐127, P<0.05. Conclusions:Although there were isolated differences, the overall trend was that the pluronic polyol and the mode of administration did not result in a significant change in bone wound healing as measured by the percentage of bone fill. Pluronic polyols may be considered as carriers for osseous graft materials. J Periodontol 2002;73:191‐197.

The presence of fibrous tissue has long been known to decrease the long‐term survival of a root‐form implant. Excessive loads on an osseointegrated implant may result in mobility of the supporting device, and excessive loads may also fracture an implant component or body. Although several conditions may cause crestal bone loss, one of these may be prosthetic overload. Excessive loads on the bone cause strain conditions to increase. These microstrains on the bone may affect the bone remodeling rate in a direct relationship. When strain conditions to the interfacial bone are in the mild overload zone, an increased bone remodeling response occurs, which results in a reactive woven bone formation that is less mineralized and weaker. Greater stresses may cause the interfacial strain to reach the pathologic overload zone and may cause microfracture of the bone, fibrous tissue formation, and/or bone resorption. Recent reports suggest that the bone remodeling rate next to an implant may be used to evaluate biomechanical conditions and their influence on the implant‐to‐bone interface. These include a number of factors, such as loading conditions, implant body surface conditions, and implant design. For a given load condition, the implant design is one of the primary factors that determine the resultant strain at the interface. A predetermined goal was established to bioengineer a dental implant to load the bone at the interface in a predetermined stress strain relationship, in order to maintain lamellar bone at the interface. A case report is presented of 2 bioengineered implants loaded for 1 year, which demonstrates that the bone was primarily lamellar in structure, the bone turnover rate was less than 5 microns/day, and was the same as the bone away from the interface. These findings corroborate those observed in a prior animal study reported with the same implant design. Although the number of implants evaluated in those 2 reports is few, they support a predetermined histological outcome.J Periodontol 2001;72:1276‐1286.

The highest specific activity of prolyl hydroxylase in lung tissue was localized in a particulate fraction which was isolated from tissue homogenates by density gradient centrifugation. Electron microscopic studies showed this fraction to be predominantly vesicles with ribosomes studding their surface. Enzymic hydroxylation by this fraction of exogenous substrate prepared from chick embryos required addition of detergent to the enzyme assay mixture. When hydroxylation was inhibited this subcellular fraction also contained proline-rich, hydroxyproline-deficient substrate which could be hydroxylated in the absence of detergent. These studies indicate a vesicular localization of prolyl hydroxylation and will facilitate future investigations of the intracellular events and regulatory mechanisms involved in collagen synthesis.

A modifiedNd:YAG laser was evaluatedfor its effect on root cementum topography and fibroblastic attachment. Fifteen extracted human teeth were curetted, sectioned, and divided into 60 areas representing 4 groups. Group I were non‐lased controls, while groups II, III, and IV were lased with the same power (4 watts, 1 second), but at 3 different laser‐target distances (1, 3, and 5 mm), thus delivering 3 different energy levels. Following lasing, 20 areas (5 per group) were examined under SEM for detection of any structural changes. Human gingival fibroblasts were cultured on both experimental and control samples of the remaining 40 areas. Photomicrographs at ×500 were obtained and the number of attached fibroblasts were counted. Results showed that lased cemental surfaces exhibited changes in surface topography which ranged from what appeared to be an apparent fusion of the surface of the covering smear layer (lowest energy level), to cracking and fissuring of the lased surface (highest energy level). When fibroblasts were cultured on the specimens, the results demonstrated the presence of a monolayer of cells on the control surfaces and on the surfaces lased with the lowest energy level (5 mm distance). Specimens lased at the mid‐energy level (3 mm) showed decreased numbers of attached cells, but not significantly different from the controls. On the other hand lasing the cementum surface at the highest energy level (1 mm distance) caused a significant decrease in the number of the attached cells as compared to the controls. The results of the present study suggests that modification of the cemental surface by the laser was dependent on the energy level. Furthermore, the energy level used (4 watts, 1 second) at 3 and 5 mm distance supported cell growth comparable to the controls. J Periodontol 1994; 65:297–302.

The purpose of this study wasto investigate if the treatment of porous polysulfone (PPSF) with various concentrations of platelet‐derived growth factor‐BB (PDGF‐BB) would stimulate the proliferation of the adherent human periodontal ligament fibroblasts (HPDLF) in culture. Sterilized PPSF cylinders were immersed in an Eagle's minimum essential medium supplemented with 0.5% fetal bovine serum and 1% penicillin/streptomycin‐containing either 0, 10, 20, or 50 ng/ml of PDGF‐BB for 24 hours. After 24 hours, the PPSF cylinders were removed and allowed to dry then placed in culture plates for each time point. Pooled HPDLF (8 × 104) and 3H‐thymidine in medium were pipetted into each well to cover the treated and control PPSF cylinders and plates were then incubated. At 1, 4, and 10 days the PPSF cylinders were removed and macromolecular precipitation was performed. Incorporation of 3H‐thymidine was measured and a 2‐way ANOVA with repeated measures was performed. In addition, determination of binding and release was performed using I125‐PDGF‐BB treated PPSF at 0, 2, 12, and 24 hours, and at 4 and 10 days. Results showed that the effects on HPDLF were significant for dose (P= 0.0012; F = 5.74) and time (P= 0.0001; F = 40.83). At 4 days, the percent increases above the control for the doses 10, 20, and 50 ng/ml were 192%, 310%, and 162% respectively. In conclusion, our findings suggest that treating PPSF with PDGF‐BB results in a significant increase in the proliferation of HPDLF cells adherent to PPSF. J Periodontol 1996;67:981–985.

Alveolar bone grafting Is an adjunctive procedure that has become increasingly popular in the rehabilitation of patients with cleft lip and palate. A histologic basis of the performance of bone grafts is required to evaluate properly different grafting materials. This, however, cannot be provided by clinical studies on humans. Therefore, an animal model with a simulated alveolar cleft is needed. A number of animal models has been previously proposed by other investigators. The problems associated with each model are presented and a surgical technique for the creation of permanent alveolar clefts in rabbits Is described. Clinical and histologic findings 6 weeks postoperatively confirm the establishment of a 1-cm wide defect with oronasal communication and healthy epithelial lining. This animal model can be efficiently used for the testing of various bone grafting materials.

In concert with studies of the effects of various pharmacologic inhibitors of corticosteroidogenesis on adrenocortical morphology, U-8113, an analog of amphenone B, was administered daily to Sprague-Dawley rats for 7, 14, 21 or 30 days. The primary morphological responses involved increases in adrenal weight, width of zona fasciculata, width of zona reticularis, intracellular lipids, mitochondrial size, mitochondrial vacuolation and crystalline-like inclusions, small coated vesicles, lysosomes, autophagic vacuoles and cholesterol ester clefts. In particular, the increases in lysosomes, coated vesicles and autophagic vacuoles containing morphologically altered mitochondria were considered reflective of mechanisms designed to maintain cellular integrity amidst functional impairment. Lipid analysis revealed marked increases in cholesterol esters and phospholipids, supportive of morphological observations. When permitted a 14 day recovery period following either 14 or 30 days of inhibitor therapy, most fine structural alterations and lipid derangements were diminished, and the cells approximated normal parameters.

To further our understanding of the immunopathologic mechanisms involved in experimental autoallergic sialadenitis of rat submandibular gland (EAS), histometric and fine structural studies were undertaken. Rats were immunized with allogeneic submandibular glands (SMG) emulsified in complete Freund’s adjuvant. Control rats were not treated (C) or adjuvant treated (At). The rats were sacrificed 7, 14, 21 and 28 days after immunization and their SMG were processed for light and electron microscopy. Groups “C” and “At” showed normal acini and ducts. The SMG at 14 days showed significant loss of acini and granular ducts, severe lymphocytic infiltration and the appearance of undifferentiated ducts. The cells of the latter showed abundant free ribosomes, few profiles of rer, no secretory granules and in some cells autophagic vacuoles. Pseudopods of many lymphocytes were found in juxtaposition to degenerating parenchymal cells, mast cells and eosinophils. The extralobular ducts were significantly increased at 7, 14, and 21 days. The immunized glands showed evidence of regeneration at 21 and 28 days. Terminal tubule cells, proacinar cells and acinar cells, at various stages of maturation, were found in the regenerating glands.

Dura plays an important role in calvarial morphogenesis. However, precisely what that role is remains unclear. We present here in vivo evidence that dura without other central nervous system components induces both chondrogenesis and osteogenesis. The mechanism is, at least in part, by proximate tissue interaction. The objectives of this experiment were to answer the following 1 Can dura actually induce osteogenesis without the influence of the underlying brain 2 What are the requirements of this durainduced heterotopic osteogenesis 3 What are the differences between dura underlying sutures and dura underlying the squamous portions of the cranial bones

A cholinesterase localization method and a monoamine histofluorescence technique were used to locate nerve fibres in regenerating rat submandibular gland autografts. Experimental rats had a portion of one submandibular gland excised and cut into small fragments which were autografted immediately into the middle one-thrid of the tongue. Control rats had a portion of one submandibular gland removed and discarded, and their tongues were sham-operated. Seven to ten weeks later, the rats were killed and the tongues were removed, frozen and sectioned in a cryostat. A light microscopical study of the tongue sections subjected to the cholinesterase technique showed that the submandibular gland autografts contained many nerve fibres that exhibited cholinesterase activity. These cholinesterase-positive nerve fibres were distributed throughout the autografts. The fibres were associated with the numerous duct-like structures and the less numerous acini. In addition, ultraviolet illumination of tongue sections after treatment with a glyoxylic acid mixture revealed histofluorescent monoaminergic nerves within the autografts. These fibres were less prominent than the cholinesterase-positive fibres and appeared to run primarily along blood vessels within the autografts. The results suggest that autonomic nerves are present within regenerating submandibular gland autografts.