Peristalsis regulation by tachykinin NK1 receptors in the rabbit isolated distal colon

In the gastrointestinal tract, tachykinin NK1 receptors are widely distributed in a number of neuronal and nonneuronal cells involved in the control of gut motor activity. In particular, in the rabbit isolated distal colon, which is a suitable model system to investigate the contribution of tachykinins as noncholinergic excitatory transmitters, the influence of NK1 receptors in the regulation of peristalsis is not known. The selective NK1-receptor antagonists SR-140333 (0.3 and 1 nM) and MEN-10930 (0.3-10 nM) significantly enhanced the velocity of rabbit colonic propulsion to submaximal stimulation. The prokinetic effect of SR-140333 was prevented by N(omega)-nitro-L-arginine (L-NNA), a nitric oxide synthase inhibitor, indicating that NK1 receptors located on nitrergic innervation exert a functional inhibitory restraint on the circular muscle and probably on descending excitatory and inhibitory pathways during propulsion. Conversely, the selective NK1-receptor agonist septide (3-10 nM) significantly inhibited colonic propulsion. In the presence of L-NNA, the inhibitory effect of septide was reverted into a prokinetic effect, which is probably mediated by the activation of postjunctional excitatory NK1 receptors.     

Competition between two aquatic detritivorous isopods – a laboratory study

The role of adult faeces in juvenile nutrition of two isopod species, Proasellus coxalis s.l. and Asellus aquaticus (L.), with similar trophic strategies and different reproductive output, has been studied in laboratory. Our aim was to consider the possible competitive mechanisms occurring at the beginning of the species coexistence using allopatric populations in single and mixed species experiments. Two series of competition experiments were performed. In the first, adult specimens were used for breeding and feeding trials. Both population dynamics and the percentage of ovigerous females and juveniles were evaluated during 10 months. Adult densities and juvenile percentage of A.aquaticus were lower in the presence of P. coxalis s.l. than when alone. At the end of the breeding experiments the dietary preferences of adults on a set of fungally conditioned leaf discs were not different among treatments. In the second series of experiments, the influence of coexistence on the feeding rates of young asellids and the relative importance of faeces and decaying plant material in their diet were investigated. Individual consumption by wild juveniles in multiple-choice laboratory experiments was measured by radioisotopes (^{32 2}P). Juveniles of P. coxalis s.l. showed the highest ingestion rates. In co-occurrence, contrary to A.aquaticus, they were able to further increase feeding on parental faeces. The role of parental faeces in the diet of the two species juveniles and the competitive dominance of P. coxalis s.l. are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Derivative emission spectrofluorimetry: Application to the analysis of newly approved FDA combination of ibuprofen and famotidine in tablets

A new combination of ibuprofen (NSAID) and famotidine (H₂ receptor antagonist) was recently approved by the FDA. It was formulated to relief pain while decreasing the risk of ulceration, which is a common problem for patients receiving NSAID. A rapid and simple derivative emission spectrofluorimetric method is proposed for the simultaneous analysis of this combination in their pharmaceutical preparation. The method is based upon measurement of the native fluorescence intensity of the two drugs at λ_ex = 233 nm in acetonitrile. The emission data were differentiated using the first (D1) derivative technique. The plots of derivative fluorescence intensity versus concentration were rectilinear over a range of 2–35 and 0.4–8 µg/mL for both ibuprofen (IBU) and famotidine (FAM), respectively. The method was sensitive as the limits of detection were 0.51 and 0.12 µg/mL and limits of quantitation were 1.70 and 0.39 µg/mL, for IBU and FAM respectively. The proposed derivative emission spectrofluorimetric method was successfully applied for the determination of the two drugs in their synthetic mixtures and tablets with good accuracy and precision. The proposed method was validated as per ICH guidelines. Copyright © 2014 John Wiley & Sons, Ltd.     

Mycetoma in the Sudan: An Update from the Mycetoma Research Centre,University of Khartoum,Sudan

This communication reports on the Mycetoma Research Centre of the University of Khartoum, Sudan experience on 6,792 patients seen during the period 1991–2014.The patients were predominately young (64% under 30 years old) males (76%). The majority (68%) were from the Sudan mycetoma belt and 28% were students. Madurella mycetomatis eumycetoma was the most common type (70%). In 66% of the patients the duration of the disease was less than five years, and 81% gave a history of sinuses discharging mostly black grains (78%). History of trauma at the mycetoma site was reported in 20%. Local pain was reported in 27% of the patients, and only 12% had a family history of mycetoma. The study showed that 57% of the patients had previous surgical excisions and recurrence, and only 4% received previous medical treatment for mycetoma. Other concomitant medical diseases were reported in 4% of the patients. The foot (76%) and hand (8%) were the most commonly affected sites. Less frequently affected sites were the leg and knee (7%), thigh (2%), buttock (2%) and arm and forearm (1%). Rare sites included the chest wall, head and neck, back, abdominal wall, perineum, oral cavity, tongue and eye. Multiple sites mycetoma was recorded in 135 (2%) of cases. At presentation, 37% of patients had massive lesions, 79% had sinuses, 8% had local hyper-hydrosis at the mycetoma lesion, 11% had regional lymphadenopathy, while 6% had dilated tortuous veins proximal to the mycetoma lesions. The diagnosis of mycetoma was established by combined imaging techniques and cytological, histopathological, serological tests and grain culture. Patients with actinomycetoma received a combination of antimicrobial agents, while eumycetoma patients received antifungal agents combined with various surgical excisions. Surgical excisions in the form of wide local excision, debridement or amputation were done in 807 patients, and of them 248 patients (30.7%) had postoperative recurrence. Different types of amputations were done in 120 patients (1.7%).     

Head and Neck Mycetoma: The Mycetoma Research Centre Experience

Mycetoma is a unique neglected tropical disease which is endemic in what is known as the “mycetoma belt”. The disease has many devastating impacts on patients and communities in endemic area and is characterised by massive deformity, destruction and disability. Mycetoma is commonly seen in the foot and hand and less frequent in other parts of the body. Mycetoma of the head and neck is a rarity and is associated with high morbidity and even mortality if not treated early. In this communication we report on 49 patients with head and neck mycetoma followed up at the Mycetoma Research Centre in Khartoum. Most of the reported patients had actinomycetoma and the majority were young adult males from mycetoma endemic areas in the Sudan. Most of them were students, farmers and workers. Prior to presentation the majority had long disease duration and the cause was multifactorial. Advanced disease with massive lesion, deformity and disability was the common presentation. There was no obvious history of local trauma, familial tendency or other predisposing factor identified in this group of patients. MRI and CT scan were the most accurate diagnostic tools to determine the disease extent. The treatment outcome was rather poor and characterised by low cure rate, poor outcome and high follows-up dropout. Such a gloomy outcome calls for structured and objective health education programs.     

hosimary: a new hAT transposon group involved in horizontal transfer

A PCR screening approach was used to search for sequences homologous to a previously described hAT transposon found in Drosophila simulans and Drosophila sechellia, named here as hosimary. In this study, 52 Drosophilidae species were analyzed and these sequences seem to be restricted to some species of the melanogaster group and Zaprionus indianus. These species present variable number of copies and most of those appear to be putatively encoding. The high hosimary sequences similarity among different species and the patchy distribution presented by this transposon strongly support the hypothesis that hosimary was horizontally transferred between the melanogaster group species and Z. indianus.     

Volatile emissions and phenolic compound concentrations along a vertical profile of <Emphasis Type="Italic">Populus nigra</Emphasis> leaves exposed to realistic ozone concentrations

Plants are exposed to increasing levels of tropospheric ozone concentrations. This pollutant penetrates in leaves through stomata and quickly reacts inside leaves, thus making plants valuable ozone sinks, but at the same time triggers oxidation processes which lead to leaf injuries. To counteract these negative effects, plants produce an array of antioxidants which react with ozone and reactive molecules which ozone generates in the leaf tissues. In this study, we measured the effect of an ozone concentration which is likely to be attained in many areas of the world in the near future (80 ppb) on leaves of the vertical profile of the widespread agroforestry species Populus nigra. Changes in (1) physiological parameters (photosynthesis and stomatal conductance), (2) ozone uptake, (3) emission of volatile organic compounds (VOCs, i.e. isoprene, methanol and other oxygenated compounds), (4) concentration of antioxidant surface compounds, and (5) concentration of phenolic compounds were assessed. The aim was to assess whether the defensive pathways leading to isoprenoids and phenolics formation were induced when a moderate and chronic increment of ozone is not able to damage photosynthesis. No visual injuries and minor changes in physiology and ozone uptake were observed. The emission of isoprene and oxygenated six-carbon (C6) volatiles were inhibited by ozone, whereas methanol emission was increased, especially in developing leaves. We interpret these results as suggesting an ontogenetic shift in ozone-treated leaves, leading to a slower development and a faster senescence. Most surface and phenolic compounds showed a declining trend in concentration from the youngest to the fully expanded leaves. Ozone reduced the concentrations of chlorogenic acid derivatives at the leaf surface, whereas in total leaf extracts a metabolic shift towards few phenolics with higher antioxidant capacity was observed.