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781.
Cartilage is categorized into three general subgroups, hyaline, elastic, and fibrocartilage, based primarily on morphologic criteria and secondarily on collagen (Types I and II) and elastin content. To more precisely define the different cartilage subtypes, rabbit cartilage isolated from joint, nose, auricle, epiglottis, and meniscus was characterized by immunohistochemical (IHC) localization of elastin and of collagen Types I, II, V, VI, and X, by biochemical analysis of total glycosaminoglycan (GAG) content, and by biomechanical indentation assay. Toluidine blue staining and safranin-O staining were used for morphological assessment of the cartilage subtypes. IHC staining of the cartilage samples showed a characteristic pattern of staining for the collagen antibodies that varied in both location and intensity. Auricular cartilage is discriminated from other subtypes by interterritorial elastin staining and no staining for Type VI collagen. Epiglottal cartilage is characterized by positive elastin staining and intense staining for Type VI collagen. The unique pattern for nasal cartilage is intense staining for Type V collagen and collagen X, whereas articular cartilage is negative for elastin (interterritorially) and only weakly positive for collagen Types V and VI. Meniscal cartilage shows the greatest intensity of staining for Type I collagen, weak staining for collagens V and VI, and no staining with antibody to collagen Type X. Matching cartilage samples were categorized by total GAG content, which showed increasing total GAG content from elastic cartilage (auricle, epiglottis) to fibrocartilage (meniscus) to hyaline cartilage (nose, knee joint). Analysis of aggregate modulus showed nasal and auricular cartilage to have the greatest stiffness, epiglottal and meniscal tissue the lowest, and articular cartilage intermediate. This study illustrates the differences and identifies unique characteristics of the different cartilage subtypes in rabbits. The results provide a baseline of data for generating and evaluating engineered repair cartilage tissue synthesized in vitro or for post-implantation analysis.  相似文献   
782.
Caryopses of a salt sensitive wheat cultivar (Triticum aestivum L. cv. Giza 163) were presoaked in 2.5 mM putrescine (Put), 5 mM spermidine (Spd) or 2.5 mM spermine (Spm) for 24 h and then subjected to 150 mM NaCl added to the growth medium for 15 d. Effects of NaCl and polyamines (PAs) on plasma membrane (PM) lipids, phospholipids, fatty acids, and free sterols were determined. NaCl treatment caused a decrease in total phospholipids, increase in saturated fatty acids and altered distribution of sterols and phospholipids. NaCl also induced increase in sterol/phospholipid ratio. PAs treatments (particularly Put and Spd) counterbalanced the NaCl deleterious effects on PM lipids.  相似文献   
783.

Background

Hypersensitivity is a rare adverse drug reaction (ADR) associated with anti-epileptic medications. Phenytoin is one of the commonly used drugs for treatment of epilepsy that encounters a hypersensitivity reaction. This reaction can be ranged from mild cutaneous rash to anticonvulsant hypersensitivity syndrome (AHS) or drug reaction with eosinophilia and systemic symptoms (DRESS) that includes fever, rash, eosinophilia and involvement of multiple internal organs.

Case presentation

A 15 year old middle eastern female patient from Gaza strip with free past medical and allergic history. She presented to An-Najah National University Hospital (NNUH) in Nablus with intermittent high grade fever, jaundice, rash and skin peeling. On examination, she had axillary and inguinal lymphadenopathy, moderate splenomegaly and diffuse maculopapular rash. The patient was on phenytoin which started 1 month prior to her presentation as a seizure prophylaxis due to previous head injury. Eventually, the patient was diagnosed with AHS/DRESS.

Conclusions

AHS is a diagnosis of exclusion and it is significantly underreported that requires a high index of suspicion. We liked to share this case and shed the light in more details on AHS/DRESS. Our goal was to help making AHS more reported in the literature in adolescent patients, as well as to make physicians more alert of this condition’s seriousness when they prescribe antiepileptic medications in particular. In this report, we included the first case of AHS which was reported in an adolescent patient in Palestine. Moreover, we reviewed the available literature for a better understanding of the pathophysiology and management of AHS. We still believe that the full understanding of the pathogenesis of AHS is lacking, and also we are lacking a clinical tool or scoring system to determine the severity of AHS/DRESS.
  相似文献   
784.
The present study was conducted to investigate the potential of Vossia cuspidata as a phytoremediator to accumulate heavy metals from polluted water bodies. Thirty-two quadrats, distributed equally in eight sites (six polluted sites along the Ismailia canal and two unpolluted sites along the Nile River) were selected seasonally for plant, water, and sediment investigations. Winter plants recorded the highest values of shoot height, diameter, and leaf width, but the lowest shoot density. Plants collected in autumn had the lowest values of leaf length, width, and area, while those collected in spring had the highest shoot density, with the lowest shoot height. Summer populations had the highest fresh and dry plant biomass, while winter plants had the lowest. Fresh production and dry biomass of V. cuspidata in the unpolluted Nile were significantly higher than those in polluted canals. Chlorophyll a and carotenoid concentrations were reduced under pollution stress. Spring plants accumulated the highest concentrations of Cr, Cu, and Pb in their root, and the lowest concentrations of Al, Cd, Cr, and Zn in their shoot. The bioaccumulation factor for most investigated metals, except Al, Cr, and Fe was greater than 1, while the translocation factor of all metals was less than 1, therefore this plant is considered to be a potential for these metals phytostabilization.  相似文献   
785.
The Persian Jird, Meriones persicus, is distributed from Eastern Anatolia to Afghanistan and western Pakistan. Six subspecies were described based on skull features and coat colours, but the validity of these subspecies is uncertain, and no molecular work has ever been conducted on this species. Iran appears to be a key geographical region in which to revise the systematic and evolutionary history of this species, because five of the six subspecies are present in this country. To evaluate the phylogeographical history and taxonomy of this species in Iran, we used a combination of genetic (cytochrome b gene sequences of 70 specimens) and geometric morphometric (2D landmarks on the ventral side of skull of 258 specimens) analyses. We also used ecological niche modelling to make inferences about the evolutionary history of these lineages. Our molecular data highlight the existence of four genetic lineages, but they only partly correspond to the previously described subspecies. Our molecular and morphometric data confirm the validity of M. p. rossicus and show that it has a wider geographical range than previously thought. M. p. gurganensis and M. p. baptistae are genetically very close. The skull of M. p. gurganensis is morphologically distinguishable from other subspecies. The subspecies M. p. persicus and M. p. baptistae are genetically distinct, but morphologically close. Meriones p. ambrosius is genetically close to M. p. persicus, and additional analyses with more specimens are needed to validate its subspecific status. The genetic structure observed in Iran seems to fit the topography and biogeography of the country and emphasize the role of the Abarkooh, Central and Lut deserts as barriers to gene flow. All intraspecific divergent events within the Persian Jird occurred during the last 1.4 My, suggesting that climatic changes probably trigger diversification within this species. Our genetic and species niche modelling results suggest that potential refugial areas persisted during glacial periods for this species in north‐western Zagros Mountains, north‐eastern Alborz Mountains and Kohrud Mountains.  相似文献   
786.
To assess the potential of the hymenopteran ectoparasitoid, Habrobracon hebetor Say as a biological control agent, we evaluated its response to different larval densities of two pyralid hosts, Palpita unionalis Hbn. and Galleria mellonella L. The former host is a serious pest of olive trees, whereas the latter is used as a factitious host in parasitoid mass rearing. In order to study the functional response of the parasitoid, five host densities (1, 2, 3, 5, 7) of either late instar larva per Petri dish were used. The shape of the functional response curve was determined using logistic regression and could be described as a type II response for both hosts, characterised by a monotonic decelerating increase in the number of hosts attacked with increasing host density. Female parasitoids allocated more eggs to the first larva attacked than all the remaining larvae. Aggregated dispersion patterns for parasitoid egg distribution at different host densities were estimated using the Green index. Multiple visits and ovipositions by females did not significantly affect the total number of progeny produced or their sex ratio. This study has generated novel information on egg laying, egg distribution and sex ratio of H. hebetor when reared on G. mellonella and has the potential to be used in the development of sustainable biological control programmes aimed at P. unionalis in olive orchards.  相似文献   
787.
Multiple sclerosis (MS) is a chronic autoimmune demyelinating neurodegenerative central nervous system disorder. The aim of the present study was to investigate the prophylactic effect exerted by the one‐time intraperitoneal injection of mesenchymal stem cells (MSCs) 1 × 106 and 14‐day intraperitoneal injection of methylprednisolone (MP) 40 mg/kg in an experimental autoimmune encephalomyelitis (EAE). EAE was induced by intradermal injection of rat spinal cord homogenate with complete Freund's adjuvant in Swiss mice. Results of MSCs and MP‐treated mice showed a significantly milder disease and fewer clinical scores compared to control mice. They suppressed tumor necrosis factor‐alpha and myeloperoxidase and increased interleukin 10, whereas thiobarbituric acid reactive substances and nitric oxide brain contents were reduced to comparable levels between treatment groups. Brain content of GSH was significantly higher in MSCs‐treated mice than control mice. It is evident that MSCs have relevant prophylactic effect in an animal model of MS and might represent a valuable tool for stem cell based therapy in MS.  相似文献   
788.
789.
790.
A new myxosporean parasite, Auerbachia maamouni n. sp., infecting the gallbladder of the golden trevally Gnathanodon speciosus Forsskål, is described, based on morphology, ultrastructure, and small subunit (SSU) rRNA gene sequencing. Of 50 fish collected from the Red Sea in Jeddah, Saudi Arabia, five were found heavily infected with mature myxospores floating free in the bile. Mature spores are pyriform to club-shaped with smooth valves, and contain a single polar capsule with an S-shaped polar filament, arranged in 13–16 polar filament coils, oriented longitudinally, with an irregular distribution on the polar capsule matrix. Spores measure 15.8 (14–17) μm in total length in lateral view, 7.9 (6–9) μm in width in apical view, with spore body length of 6.2 ± 0.4 (5–7) µm. The ellipsoidal polar capsule has two adjusted lateral folds 7.6 (6–8) µm long and 2 (2–3) µm wide. The new species is distinguished from other species of the genus based on spore morphometry and molecular data. The phylogenetic tree constructed using Maximum Likelihood and Bayesian Inference analysis of SSU rDNA sequence data supported the phylogenetic position of A. maamouni n. sp. among the species of Auerbachia Meglitsch, 1968 sequenced to date. Analysis of the SSU rDNA sequence data also supported the assumption that Auerbachia is closely related to members of the genera Coccomyxa Léger & Hesse, 1907, Zschokkella Auerbach, 1910 and Myxidium Bütschli, 1882, whose members inhabit the gallbladder of marine teleost fishes.  相似文献   
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