Emerging Biomedical Applications of Nano-Chitins and Nano-Chitosans Obtained via Advanced Eco-Friendly Technologies from Marine Resources

The present review article is intended to direct attention to the technological advances made in the 2010–2014 quinquennium for the isolation and manufacture of nanofibrillar chitin and chitosan. Otherwise called nanocrystals or whiskers, n-chitin and n-chitosan are obtained either by mechanical chitin disassembly and fibrillation optionally assisted by sonication, or by e-spinning of solutions of polysaccharides often accompanied by poly(ethylene oxide) or poly(caprolactone). The biomedical areas where n-chitin may find applications include hemostasis and wound healing, regeneration of tissues such as joints and bones, cell culture, antimicrobial agents, and dermal protection. The biomedical applications of n-chitosan include epithelial tissue regeneration, bone and dental tissue regeneration, as well as protection against bacteria, fungi and viruses. It has been found that the nano size enhances the performances of chitins and chitosans in all cases considered, with no exceptions. Biotechnological approaches will boost the applications of the said safe, eco-friendly and benign nanomaterials not only in these fields, but also for biosensors and in targeted drug delivery areas.     

Studies on the Physiological Chemistry of the Tibio-Tarsal Synovial Fluid of Healthy Bovines

The physical properties, chemical composition and cytological content of the synovial fluid of healthy native breed cattle, obtained by tibio-tarsal arthrocentesis, was studied.     

Description of the rusts from Kemaliye (Erzincan,Turkey)

Twenty-two rust diseases caused by Melampsora euphorbiae, M. lini var. lini, Phragmidium mucronatum var. mucronatum, Ph. sanguisorbae, Gymnosporangium cornutum, G. confusum, G. tremelloides, Puccinia acarnae, P. annularis, P. eryngii, P. heterophyllae, P. hieracii, P. jasmini, P. menthae, P. nigrescens, P. pulverulenta, P. punctata, Uromyces dianthi, U. pisi-sativi, U. polygoni-avicularis, U. striatus and Pileolaria terebinthi were identified from Kemaliye (Erzincan) in Turkey. Puccinia heterophyllae is reported for the first time from Turkey.     

The use of air‐coolers in broiler houses under subtropical conditions in Iraq

1. Under summer conditions in north Iraq, 2 000 chicks were reared for 56 d in two broiler houses. One house was provided with two air‐coolers. The birds were housed at densities of eight to 16 birds/m².

2. Differences in weight gain between birds in cooled and uncooled houses ranged from 101.5 g at eight birds/m² to 385 g at 16 birds/m². Food consumption increased gradually with increasing bird density. Food conversion efficiency, meat yield and carcass conformation were much better in the cooled house than under conventional conditions.

3. The financial return/m² ranged from 2.30 to 4.51 ID¹ in the cooled house, compared with 2.01 to 2.77 ID in the uncooled house at different floor densities.     

New Bruce-ladder multiplex PCR assay for the biovar typing of Brucella suis and the discrimination of Brucella suis and Brucella canis

Rapid and specific identification of Brucella suis at the biovar level is necessary because some of the biovars that infect animals are pathogenic for humans. None of the molecular typing methods described so far are able to discriminate B. suis biovars in a single test and differentiation of B. suis from Brucella canis by molecular approaches can be difficult. This article describes a new multiplex PCR assay, Suis-ladder, for fast and accurate identification of B. suis at the biovar level and the differentiation of B. suis, B. canis and Brucella microti. An advancement of the original Bruce-ladder PCR protocol which allows the correct discrimination of all known Brucella species is also described.     

Combined effect of deficit irrigation and potassium fertilizer on physiological response,plant water status and yield of soybean in calcareous soil

A 2-year field experiment (2013 and 2014) was conducted in calcareous soil (CaCO₃ 19.2%), on soybean grown under three irrigation regimes 100%, 85% and 70% of crop evapotranspiration combined with three potassium (K₂O) levels (90, 120 and 150 kg ha^?1). The objective was to investigate the complementary properties of potassium fertilizer in improving soybean physiological response under water deficit. Plant water status (relative water content RWC, chlorophyll fluorescence F_v/F₀ and F_v/F_m), had been significantly affected by irrigation or/and potassium application. Potassium improved growth characteristics (i.e. shoot length, number, leaf area and dry weight of leaves) as well as physiochemical attributes (total soluble sugars, free proline and contents of N, P, K, Ca and Na). Yield and yield water use efficiency (Y-WUE) were significantly affected by irrigation and potassium treatments. Results indicated that potassium application of 150 and 120 kg ha^?1 significantly increased seed yield by 29.6% and 13.89%, respectively, compared with 90 kg ha^?1 as average for two seasons. It was concluded that application of higher levels of potassium fertilizer in arid environment improves plant water status as well as growth and yield of soybean under water stress.     

Investigation of mechanical properties of developed antimicrobial PPsuture/Ag nanocomposite

In order to prevent surgical complications due to microbial infections, we have developed polypropylene suture grafted with silver nanoparticles (PPsuture/Ag nanocomposite) by a simple immersion procedure. Physical and mechanical properties of developed suture are investigated. Suture surface characteristics are examined by scanning electron microscopy (SEM) imaging and atomic force microscopy (AFM). Silver content on suture surface was determined by Inductively coupled plasma atomic emission spectroscopy (ICP-AES). The mechanical properties of developed antibacterial PP suture/Ag were studied. We note that proposed silver coating method has not affected mechanical performances of suture. Antimicrobial performances of PP suture/Ag nanocomposites against S. aureus and E. coli colonies were also investigated.     

Möglichkeiten und Genzen des integrierten Pflanzenschutzes im Gemüsebau

Since the presence of pest species on cultural plants does not mean always a real economical loss, crop loss assessment is to be considered the first step towards developing integrated control in vegetable crops. In our field-experiments there was no difference in the yield between treated and untreated cauliflowers or cabbage, inspite of a considerable attack ofErioischia brassicae Bouché in the area. Also the application of a herbicide (Aretit) to pea-culture did not increase the yield. Establishing the ‘economic threshold’ for potential pests is illustrated on the Cabbage maggot fly inBrassicas, and weeds in pea-culture. Different ways of helping to reduce the population density of a definite pest species were discussed: choosing the most adequate cultivation site, sanitary measures, intercrop relationships, using resistant crop varietes, choice and application of fertilizers. Biological control measures promise a good possibility:Aleochara-release againstE. brassicae in the UdSSR, sterile-male-technique against the onion fly in the Netherlands. Properties of pesticides allowed in integrated control programmes were discussed with examples: Non-persistance, high selectivity, accumulation-danger from previous crops etc. Lastly some problems caused by incorrect interpretation of the expression ‘integrated control’ as well as the possible limits of the procedure were discussed.     

Evaluation of efficacy of several disinfectants against Campylobacter jejuni strains by a suspension test

The objective of this study was to determine the efficacy of 16 active compounds and 11 commercial disinfectants against Campylobacter jejuni. Two reference strains (one of avian origin and the other isolated from bovine) and two avian field strains were tested in suspension test in the presence and absence of serum. Chloramine-T, povidone–iodine (1% available iodine), cetylpiridinium chloride, ethanol, isopropanol, chlorhexidine digluconate, formaldehyde, phenol, and 10 of the 11 commercial formulations (eight of them based on quaternary ammonium compounds) showed an excellent disinfectant capability, resulting in the highest level of reduction (>6-log₁₀) in colony-forming units of the four C. jejuni strains compared regardless of the presence or absence of organic material. These compounds might be helpful in the adoption of environmental control measures against C. jejuni.     

Recent research in Roumania on blackleg and bacterial soft rot of potato

Summary Potato blackleg has been known in Roumania for more than 35 years, but has become increasingly serious in recent times. The disease is mainly restricted to the central and northern regions, which have a rainy climate with moderate temperatures. In areas where the climate is warm and dry, the disease appears only sporadically, and even then, its development is slow. The principal means of transmission of the disease from one year to another is by infected tubers, the causal organ does not persist long in unsterile soil. Potato blackleg and soft rot in Roumania is produced not only byE. atroseptica, for an important part in the disease complex especially in storage is played by the bacteriaE. carotovora andE. aroideae. E. atroseptica, owing to its special preference for the stems of the plants, is considered as the principal pathogenic agent, while the other two organisms occur more frequently in the tubers. It is considered that the divergent characteristics of the organisms justify keeping them as two or even three separate species and not as variants of a single species.

---

Zusammenfassung In den Jahren 1961 bis 1963 wurden am Biologischen Institut Traian Savulescu in Bukarest, Rum?nien, Untersuchungen durchgeführt über die Verbreitung der Schwarzbeinigkeit bei Kartoffeln im Zusammenhang mit den klimatischen Verh?ltnissen in Rum?nien, mit den Bedingungen, unter welchen die Infektion und die übertragung der Krankheit stattfindet, mit der Etiologie der Krankheit in Rum?nien und mit gewissen charakteristischen Eigenschaften der Krankheitserreger. Kartoffel-Schwarzbeinigkeit ist in Rum?nien schon seit mehr als 35 Jahren bekannt, aber in letzter Zeit hat sie ernstere Formen angenommen. Die Infektion im Feld schwankt von 1–15% und nimmt w?hrend der Lagerung zu. Die Krankheit beschr?nkt sich haupts?chlich auf die zentralen und n?rdlichen Regionen des Landes, wo ein regnerisches Klima mit m?ssigen Temperaturen vorherrscht. Im Süden, wo Frühling und Sommer in der Regel heiss und trocken sind, scheint sie eigentlich nicht vorzukommen, selbst nicht in Feldern, die mit Knollen aus befallenen Gebieten bepflanzt sind. Es ist festgestellt worden, dass die übertragung dieser Krankheit von einem Jahr auf das andere haupts?chlich durch befallene Knollen geschieht. Der Boden bildet nur in dem Mass eine Infektionsquelle, als er nicht verfaulte Reste von kranken Pflanzen enth?lt. Es wurde dargelegt, dass die Bakterien in nicht sterilem Boden ihre überlebensf?higkeit rasch verlieren (Tabelle 1). Was die Etiologie der Schwarzbeinigkeit betrifft, wurde herausgefunden, dass nebenErwinia atroseptica—in Rum?nien bis jetzt als die einzige Ursache dieser Krankheit angenommen — auchE. carotovora undE. aroideae, speziell w?hrend der Lagerung, eine wichtige Rolle im Krankheitskomplex spielen. Unsere Beobachtungen und Untersuchungen haben ergeben, dassE. atroseptica der Hauptkrankheitserreger im Feld ist, der besonders die Stengel bef?llt. Die beiden andern Bakterien kommen ebenfalls vor, doch werden sie gew?hnlich auf den Knollen am Lager gefunden, wo sie — unter günstigen Bedingungen — einen viel h?ufigeren Befall erzeugen k?nnen alsE. atroseptica. Es wurde festgestellt, dass sowohl Eigenschaften, wie der Grad der Pathogenit?t an Stengeln und Knollen, Reaktionen auf Zuckern und besonders das Verhalten auf Maltose und auf durchtr?nktes Korn-Pepton-Glukose-Agar-Medium, das Wachstum bei hohen Temperaturen (Tabelle 2) und serologische Reaktionen (Tabelle 3) wie auch toxische und immunologische Wirkungen auf Tiere bei der Unterscheidung der drei Bakterien von Nutzen sind. Es wird darauf hingewiesen, dass die hier berichteten Ergebnisse die Ansicht jener Forscher best?rken und rechtfertigen, die glauben, dass die drei Bakterien als verschiedene Arten betrachtet werden sollten.

---

Résumé A l'Institut de Biologie Traian Savulescu à Bucarest. Roumanie, les recherches suivantes ont été effectuées durant la période 1961–1963; l'apparition de la maladie de la jambe noire en relation avec les conditions climatiques en Roumanie, les conditions sous lesquelles ont lieu l'infection et la transmission de la maladie, l'étiologie de la maladie en Roumanie et certains caractères des pathogènes. La jambe noire de la Pomme de terre est connue en Roumanie depuis plus de 35 ans mais est devenue progressivement grave dans les derniers temps. L'infection dans les champs varie de 1 à 15% et augmente pendant la conservation. La maladie est essentiellement limitée aux régions du centre et du nord du pays qui ont un climat pluvieux et des températures modérées. Dans le sud, où le printemps et l'été sont habituellement chauds et secs, la jambe noire semble être réellement absente, même dans les champs plantés avec des tubercules provenant de régions infectées. Il a été établi que la transmission de la maladie d'une année à l'autre a lieu principalement par les tubercules infectés, le sol étant la source d'infection dans la seule mesure où il contient des restes non détruits de plantes malades. Il a été démontré que les bactéries perdent rapidement leur viabilité dans les sols non stériles (Tableau 1). Concernant l'étiologie de la jambe noire, on a trouvé que outreErwinia atroseptica que, jusqu'à présent, on croyait être la seule cause de la maladie en Roumanie,E. carotovora etE. aroideae jouent également un r?le important, spécialement pendant la conservation. Selon nos observations et expériences,E. atroseptica est le principal agent pathogène dans le champ, montrant une préférence marquée pour les tiges, tandis qu'apparaissent aussi les deux autres bactéries qui, toutefois, sont plus communément trouvées sur les tubercules pendant la conservation; à ce moment, sous des conditions favorables, les attaques de ces dernières peuvent être beaucoup plus grandes que celles deE. atroseptica. Les déterminations des comportements suivants se sont révélées pleinement utiles pour différencier les trois bactéries: les degrés d'attaques sur tiges et tubercules, les réactions sur sucres et spécialement leurs réactions sur maltose et sur milieu agar glucose peptone de grains trempés, leur développement à hautes températures (Tpableau 2) et leurs réactions sérologiques (Tpableau 3) aussi bien comme effets toxiques qu'immunologiques sur les animaux. Les résultats rapportés ici prouvent et développent les vues de ces chercheurs qui croient que les trois bactéries seraient à considérer comme espèces séparées.

---

---

Paper read to the Pathology Section of the Second Triennial Conference of the European Association for Potato Research, Italy, September 1963.