Fouling bryozoans in Argentine harbours (Southwest Atlantic): new records and the description of a new species.

Non-indigenous bryozoans are frequent components of biofouling assemblages in harbour environments worldwide. We performed a survey of artificial hard substrates in six harbours spanning 16 degrees of latitude along the coast of Argentina, from Ingeniero White (38º47' S) to Ushuaia (54º48' S). Microeciella argentina n. sp., distributed in warm-temperate waters of northern Patagonia and Buenos Aires Province, is described. The non-indigenous species (NIS) Callopora dumerilii, Smittoidea spinigera and Stephanollona boreopacifica are recorded here for the first time in the Southwest Atlantic. Their occurrence in fouling assemblages of warm-temperate harbours and their previous absence in these areas suggest that they probably arrived in Argentina by international shipping traffic. Callopora dumerilii is native to Europe and the northeast Atlantic. Smittoidea spinigera and Stephanollona boreopacifica are native to China and Korea, respectively. The morphological differences between S. spinigera and the Californian species S. prolifera, which is invading European harbours in the North Sea, are discussed. Bugula neritina, Bugulina flabellata, Cryptosula pallasiana and Fenestrulina delicia, common in harbours of Buenos Aires Province, are here recorded in Patagonia, highlighting the importance of regional shipping traffic to secondary spread of NIS. Arachnidium fibrosum, Buskia socialis, Anguinella palmata, Aetea cultrata, Bicellariella edentata and Exochella moyanoi, previously known from Brazil, and Hippothoa divaricata, are here recorded in Argentina. This study shows that warm-temperate harbours in Buenos Aires Province and northern Patagonia are particularly prone to the introduction of non-indigenous bryozoans.

Urinary Incontinence Secondary to Fecal Impaction in a Patient With Likely Undiagnosed Hirschsprung's Disease.

Hirschsprung's disease is caused by the failure of migration of neural crest cells to the hindgut, causing a lack of development of ganglion cells in the submucosal and myenteric plexuses of the colonic wall. Hirschsprung's disease most often presents in infants with failure to pass meconium in the first two days of life. We present the case of an eight-year-old male with chronic constipation since birth who presented to the emergency department with signs concerning spinal cord compression. To our knowledge, this is the first of such a case presenting with urinary incontinence.

Toxicity of crude and detoxified Tityus serrulatus venom in anti-venom-producing sheep.

Specific anti-venom used to treat scorpion envenomation is usually obtained from horses after hyperimmunization with crude scorpion venom. However, immunized animals often become ill because of the toxic effects of the immunogens used. This study was conducted to evaluate the toxic and immunogenic activities of crude and detoxified Tityus serrulatus (Ts) venom in sheep during the production of anti-scorpionic anti-venom. Sheep were categorized into three groups: G1, control, immunized with buffer only; G2, immunized with crude Ts venom; and G3, immunized with glutaraldehyde-detoxified Ts venom. All animals were subjected to clinical exams and supplementary tests. G2 sheep showed mild clinical changes, but the other groups tolerated the immunization program well. Specific antibodies generated in animals immunized with either Ts crude venom or glutaraldehyde-detoxified Ts venom recognized the crude Ts venom in both assays. To evaluate the lethality neutralization potential of the produced sera, individual serum samples were pre-incubated with Ts crude venom, then subcutaneously injected into mice. Efficient immune protection of 56.3% and 43.8% against Ts crude venom was observed in G2 and G3, respectively. Overall, the results of this study support the use of sheep and glutaraldehyde-detoxified Ts venom for alternative production of specific anti-venom.

Changes in Spectral Properties, Chlorophyll Content and Internal Mesophyll Structure of Senescing Populus balsamifera and Populus tremuloides Leaves.

In this paper we compare leaf traits and spectral reflectance for sunlit andshaded leaves of Populus tremuloides and Populus balsamifera during autumnsenescence using information derived from an Analytical Spectral Devise (ASD) FullRange spectrometer. The modified simple ratio (mSR705) and modified normalizeddifference index (mND705) were effective in describing changes in chlorophyll contentover this period. Highly significant (P less than 0.01) correlation coefficients were found betweenthe chlorophyll indices (mSR705, mND705)) and chlorophyll a, b, total chlorophyll andchlorophyll a/b. Changes in mesophyll structure were better described by the plantsenescence reflectance index (PSRI) than by near-infrared wavebands. Overall, P.balsamifera exhibited lower total chlorophyll and earlier senescence than P. tremuloides.Leaves of P. balsamifera were also thicker, had a higher proportion of intercellular spacein the spongy mesophyll, and higher reflectance at 800 nm. Further research, using largersample sizes over a broader range of sites will extend our understanding of the spectraland temporal dynamics of senescence in P. tremuloides and P. balsamifera and will beparticularly useful if species differences are detectable at the crown level using remotelysensed imagery.