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الملخص: أهداف البحث: تهدف هذه الدراسة إلى تحسين تكوين حبيبات هلامة ''ألجينات الأغاروز'' وعوامل التذويب الخاصة بها لاستخدامها المحتمل في نقل الخلايا الجذعية. طرق البحث: تم اختبار تركيزات مختلفة من الأغاروز والألجينات وكلورايد الكالسيوم لبناء حبيبات هلامة مائية. تم تسجيل معدل التحلل ونسبة الانتفاخ لكل عينة هلامة مائية. تم استخدام هلامة ''ألجينات الأغاروز'' المحسنة لتغليف الخلايا الجذعية من أسنان بشرية لبنية متساقطة (شيد). تم أيضًا إجراء تحسين عوامل الإذابة واختبارها باستخدام الخلايا المغلفة بالهلامة المائية. النتائج: تم إثبات أن التركيز المختار لمكونات هلامة ''ألجينات الأغاروز'' نجح في تغليف ''شيد'' والتي تظل قابلة للحياة حتى اليوم العاشر. تم تسجيل متوسط دقيقتين لتحلل الهلامة المائية التي تغلف ''شيد''، باستخدام عامل إذابة يتكون من 100 ملي سيترات الصوديوم و 100 ملي مولار من إيديتات الكالسيوم ثناي الصوديوم (إيديتا). تم تسجيل صلاحية خلية ''شيد'' التي تم إطلاقها بعد اليوم العاشر من التغليف بنسبة 29.1٪. الاستنتاجات: أوضحت الدراسة الحالية أن تركيزات كل من الأغاروز والألجينات وكلورايد الكالسيوم ترتبط بمعدل تحلل حبيبات الهلامة المائية ونسبة الانتفاخ. يمكن لـ ''شيد'' البقاء على قيد الحياة في بيئة هلامة مائية لمدة 10 أيام على الأقل دون تغيير وسط الاستزراع. يسمح تحسين عامل الذوبان بالتفكك المناسب لهيكل الهلامة المائية، مما يؤدي إلى إطلاق الخلايا الجذعية من حبيبات هلامة ''ألجينات الأغاروز'' بعد فترة النقل مع السماح للخلايا بالبقاء قابلة للحياة. Abstract: Hydrogels have potential uses in various biological applications because of their unique characteristics. Fine-tuning of agarose–alginate (Ag–Al) hydrogel components improves the mechanical characteristics of the final construct for cell encapsulation and transportation. Formulation of suitable dissolving agents may enable the release of encapsulated cells for further applications in laboratory or clinical settings. Objectives: This study aimed at optimizing the composition of Ag–Al hydrogel beads and their dissolving agents for potential use in the transportation of stem cells. Methods: Various agarose, alginate, and CaCl2 concentrations were tested to construct hydrogel beads. The degradation rate and swelling ratio of each hydrogel sample were recorded. The optimized Ag–Al hydrogels were used for encapsulation of stem cells from human exfoliated deciduous teeth (SHED). Optimization of dissolving agents was performed and tested with the hydrogel-encapsulated cells. Data were statistically analyzed in SPSS. Results: The selected concentration of Ag–Al hydrogels components was successfully demonstrated to encapsulate SHED, which remained viable until day 10. An average of 2 min was required for degradation of the hydrogel with encapsulated SHED by a dissolving agent consisting of 100 mM sodium citrate and 100 mM EDTA. The cell viability of SHED released after day 10 of encapsulation was 29.1%. Conclusion: Alteration of Ag-Al components has considerable influence on the mechanical properties of the constructed hydrogel. The feasibility of performing the optimized cell encapsulation protocol, as well as the dissolving step, may provide a useful guide for the transportation of viable cells between countries, for medical research.

Organically-derived biofertilizers and biostimulants, developed from harvested materials such as seaweed and waste from animal and fish processing, are currently the subject of much fundamental and applied research. These products have significant potential in reducing synthetic fertilizer inputs to horticultural, arable, and pasture-based agricultural systems, although there is frequently some ambiguity over the magnitude and consistency of any positive effects these products may have on plant performance. This study examined the effects of organically-derived plant growth promoters (PGPs) available in New Zealand on the early vegetative growth of 16 plant species maintained under glasshouse conditions. When applied as a root drench to low nutrient potting mix, the effects of the PGPs on seedling shoot growth were strongly related to the NPK contents of the applied solutions. Any positive effects on shoot growth were, on average, reduced when the seedlings were maintained in higher nutrient growing media. Applying the PGPs at concentrations twice, and four times, the recommended concentration, only caused further growth responses when the PGPs contained high levels of nutrients. Applying the PGPs as a foliar spray had negligible effects on shoot growth. Overall, the results of these trials suggest that the positive effects of applying some organically-derived PGPs on seedling growth are a function of the PGP nutrient content, and not due to any indirect effects related to phytohormone pathways or modification of rhizosphere microorganisms.

BACKGROUND: Recently, the number of implants placed worldwide has increased tremendously, so as the prevalence of peri-implant complications. AIM: This cross-sectional study aimed to determine the prevalence of peri-implant diseases and technical complications of the implant-supported single crown (ISC) in the population of Kedah State, Malaysia. The characteristics of patients and implants associated with the peri-implant diseases were also explored. MATERIALS AND METHODS: All the patients who received an ISC between January 2008 and December 2016 at a public periodontal clinic and had a loading time between 2 and 10 years were identified. Their medical and radiographic records were examined. A patient and implant-based prevalence analysis of peri-implant diseases and complications were conducted. RESULTS: Twenty-three patients with a total of 43 implants were included in the analysis. Most of the patients were under 65 years of age (69.6%). The prevalence of peri-mucositis and peri-implantitis at the patient's level were both 30.4%. They respectively involved 20.9% and 18.6% of the implants. Poor oral hygiene at the time of last follow-up showed a significant association with the peri-implant diseases. However, the roles of the implants characteristics were insignificant. No implants failed after the placement of a supra-structure, while 3 implants (7%) were reported to have technical complications. CONCLUSIONS: The complications of ISC took placed in a considerable proportion of the studied population during long-term follow-up. As the poor plaque control proved to be the major risk factor of peri-implant diseases, strategies to improve their awareness of oral hygiene are warranted. [ABSTRACT FROM AUTHOR]

The effect of the magnetic field on the magnetic properties of NiFe/Cu composite wires electroplated under a longitudinal magnetic controlling field is presented. Composite wire samples of 20-μm-diameter Cu electroplated with a layer of Permalloy™ (Ni[sub 80]Fe[sub 20]) under the influence of a longitudinal magnetic field of intensities ranging from 0 to 400 Oe were produced, and the microstructure and magnetic properties were measured. The results showed that the longitudinal magnetic field in the composite wire plating makes the packing of the crystals in the plated layer more orderly, and thus increases the uniformity and magnetic softness of the plated material. It also shifts the magnetic anisotropy of the plated layer from circumferential to longitudinal, and increases the critical frequency of the plated composite wire in magnetoimpedance effect testing, at which the magnetoimpedance ratio reaches the maximum. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have identified a pathogenic fungus that is responsible for fruit rot and leaf abscission in Chinese pear (Pyrus bretshneideri Rehd., cv. Dangshansuli). Six isolates of the fungus were obtained from diseased fruit and leaves and purified from single conidiospore cultures grown on potato-dextrose agar medium. The internal transcribed spacer (ITS) region of their ribosomal DNA was amplified, cloned, and sequenced. The results indicated that the rDNA-ITS sequences of all six isolates were identical to those of the anthracnose pathogens isolated from Taiwanese jujube (FJ233185) and Japanese pear (AB219012). This indicates that the disease observed in Chinese 'Dangshangsuli' pear was caused by the pathogen Colletotrichum gloeosporioides Penz, and/or its teleomorph, Glomerella cingulata. To determine an appropriate control strategy, 21 commercial fungicides were screened, and nine were found to be effective at inhibiting mycelial growth and the germination of conidia using controlled in vitro tests. Tests performed in 2009 and in 2010 revealed that three of these fungicides, Mancozeb, Bilu No. 2, and Triram, were efficient at controlling the disease. These results provide evidence for the most appropriate fungicides to use to control anthracnose disease in Chinese 'Dangshansuli' pear. [ABSTRACT FROM AUTHOR]

Chinese apricot (Prunus armeniaca L.) shows gametophytic self-incompatibility (GSI) controlled by a single locus containing at least two linked genes [i.e., the S-RNase gene and the pollen-expressed SFB (or SLF) gene] as do other fruit species in the family, Rosaceae. To elucidate the S-genotypes of 14 native Chinese apricot cultivars, PCR was performed using primers designed from Prunus S-RNase and SFB consensus sequences. After cloning and sequencing the PCR products, the S-genotypes of all 14 apricot cultivars were determined, and eight new S-RNase alleles and nine SFB alleles were identified. The S-RNases shared typical structural features with S-RNases from other Prunus spp. exhibiting GSI. The SFB genes showed similar structural characteristics to SFB genes in other Prunus spp. The intron sequences of the SFB genes revealed sequence and length polymorphisms. The deduced level of amino acid sequence identity for the eight new S-RNase alleles was 66.4 - 100% in P armeniaca, while the similarity of the SFB alleles was 73.7- 98.6%.The physical distances between the SFB and S-RNase genes was determined exactly in the S9, S11, S17, and S26-haplotypes, confirming that the S-RNase and SFB genes were linked. The range of distances between the two genes was 299 - 1,061 bp. This study increases our knowledge on the S-genotypes of apricot native to China, and enriches our genomic information on GSI in the Prunus genus. [ABSTRACT FROM AUTHOR]

Prunus mume (Japanese apricot) cultivars are self-incompatible and orchards require pollinator cultivars to guarantee optimal fruit production. Identification of the self -incompatibility (S) genotypes of P mume cultivars is therefore useful for choosing pollinators and for breeding. To elucidate the S-genotypes of eleven Chinese and one introduced cultivar, PCR was performed with primers amplifying the variable second intron of the S-RNase gene. The S-genotyping results were as follows: S4 S 12 for `Dantaofen'; S3S4 for `Duoezhusha'; S12S13 for `Fubantiaozhi'; S15S16 for `Hongding'; S13S14 for `Longyanmei'; S5S 11 for `Musashino'; S10S14 for `Xiaoyezhugan'; and S3S15 for `Qingfeng', `Qingjia', `Xiyeqing', `Dayeqing' and `Changnong 17'. We identified seven new S-RNase alleles, S10- Nase to S16-RNase, deposited in GenBank under the accession numbers: DQO1115O, DQ201191, DQ201192, DQ345781, DQ768219, DQ903312 and EF990750, respectively. [ABSTRACT FROM AUTHOR]