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Biomaterials applied as carriers for controlled drug delivery offer many advantages over the conventional systems. Among them, the increase of treatment effectiveness and also a significant reduction of toxicity, due to their biodegradability property, are some special features. In this work, microspheres based on the protein Zein (ZN) and ZN associated to the natural polymer Chitosan (CHI) were prepared and characterized. The microspheres of ZN and ZN/CHI were characterized by FT-IR spectroscopy and thermal analysis, and the morphology was analyzed by SEM images. The results confirmed the incorporation of CHI within the ZN-based microspheres. The morphological analysis showed that the CHI added increased the microspheres porosity when compared to the ZN microspheres. The chemical and physical characterization and the morphological analysis allow inferring that ZN/CHI microspheres are good candidates to act as a carrier for controlled drug release.

Numerous coastal communities, existing in archipelagic countries like the Philippines, depend on groundwater for their daily sustenance. Groundwater can be adversely affected by saltwater intrusion and becomes brackish water, with salinity ranging from 0.5ppt to 17ppt. Consumption of brackish water may cause kidney ailments and death to terrestrial plants.

"A domestic hen showing infraorbital swelling was presented for a routine classroom demonstration of avian diagnostics. At necropsy, tiny whitish caseo-calcareous nodules were found in the subcutaneous tissues of the carcass, produced by the subcutaneous fowl mite, Laminosioptes cysticola. Gallibacterium anatis biovar haemolytica was isolated from the infraorbital sinus, it containing a caseous exudate. During necropsy, a conspicuous cyst was found in the abdominal cavity. Microscopic examination of the internal lining of the cyst revealed a single cuboidal to columnar, ciliated epithelium, leading to a diagnosis of oviductal cyst. Also, the microscopic examination of the heart, lung, liver and kidney reveal a multifocal infiltration of lymphoma cells. It appears the first case of simultaneous presentation of these conditions from a single chicken."

Background: It is difficult to study human colonic motility under physiologic conditions. An important limitation associated with prolonged colonic recording is the failure of the sensors to resist normal expulsive forces. Method: In this article we describe a method of endoscopically positioning a manometric catheter by using clips in conjunction with a solid-state catheter. With the use of a rotatable clip-fixing device loaded on to a colonoscope, the manometric catheter was clipped to the colonic mucosa. Results: Recordings for up to 120 hours were obtained from 6 subjects without apparent migration of the catheter assembly. No complications were noted, the catheter does not interfere with defecation, and defecation does not result in its expulsion. Conclusion: The current technique will allow reliable ambulatory measurements over prolonged periods of time in relatively comfortable and unrestrained subjects. This technique should increase our understanding of normal and abnormal colonic motility.

Transesterification and epoxide ring-opening reactions are two mechanism routes that explain chemical modifications of macromolecules by glycidyl methacrylate (GMA). Although the coupling reaction of the GMA with macromolecules has widely been investigated, there are still mechanisms that remain to be explained when GMA is processed in an aqueous solution at different pH conditions. To this end, reaction mechanisms of poly(vinyl alcohol) (PVA) and poly(acrylic acid) (PAAc) by GMA in water in acidic and basic conditions were investigated thoroughly. The presence of hydroxyl groups in PVA and carboxyl groups in PAAc allowed for a better evaluation of the reaction mechanisms. The analysis of the (1)H and (13)C NMR spectra clearly demonstrated that the chemical reactions of GMA with carboxyl groups and alcohols of the macromolecules in an aqueous solution are dependent on pH conditions. At pH 3.5, the GMA reacts with both the carboxylic and the hydroxyl groups through an epoxide ring-opening mechanism. At pH 10.5, the GMA undergoes a hydrolysis process and reacts with hydroxyl groups by way of both the transesterification and the epoxide ring-opening mechanisms, whereas the ring-opening reaction is the preferential pathway.

Osteoclast and their mononuclear cell precursors are present within the bone microenvironment at sites of physiologic and pathologic bone resorption. Analysis of tissues from sites of bone resorption reveal that cells expressing the full morphological and functional properties of mature osteoclasts are restricted to the immediate bone surface. We hypothesize that in addition to cytokines, components of the bone matrix and specific cell surface receptors on osteoclasts and their precursors play an essential role in determining the genetic profile and functional properties of fully differentiated resorbing osteoclasts. We have employed expression profiling, with an in vitro model of matrix-dependent osteoclast differentiation, to identify the molecular pathways by which bone matrix-interactions induce terminal osteoclast differentiation and activation. In preliminary studies, we have identified unique genes and transcriptional pathways that are induced by interaction of osteoclast precursors with specific components of the mineralized bone matrix. The authenticity of the gene profiles, as markers of osteoclast differentiation and activation, have been provisionally validated using an in vivo animal bone implantation model and by examination of tissues from patients with specific forms of pathologic osteoclast-mediated bone resorption. The ultimate goal of our studies is to identify new molecular targets for inhibiting osteoclast-mediated bone loss in disorders of pathologic bone loss. The early work of Walker et al. (Walker 1972) in parabiotic animals, and the subsequent studies of Burger et al. (Burger, Van der Meer, van de Gevel, et al. 1982) using a co-culture model with fetal bone rudiments and bone marrow-derived cells, have helped to establish that osteoclasts are derived from macrophage precursors of colony forming unit-macrophage (CFU-M lineage). As such, they share a common hematopoietic origin with other CFU-M lineage cells, including tissue macrophages that populate the lung (alveolar macrophages), liver (Kupfer cells), synovium (synovial macrophages) and other organs. They also share a common lineage

Specific combustion programs (Gaseq, Chemical equilibria in perfect gases, Chris Morley) are used to model dioxin and formation in the incineration processes of urban solid wastes. Thanks to these programs, it is possible to establish correlations with the formation mechanisms postulated in literature on the subject. It was found that minimum oxygen quantities are required to obtain a significant formation of these compounds and that more furans than dioxins are formed. Likewise, dioxin and furan formation is related to the presence of carbon monoxide, and dioxin and furan distribution among its different compounds depends on the chlorine and hydrogen relative composition. This is due to the fact that an increased chlorine availability leads to the formation of compounds bearing a higher chlorine concentration (penta-, hexa-, hepta-, and octachlorides), whereas an increased hydrogen availability leads to the formation of compounds bearing a lower chlorine number (mono, di-, tri-, and tetrachlorides). Fil: Moreno Piraján, Juan Carlos. Universidad de los Andes; Colombia Fil: García Ubaque, C. A.. Universidad de los Andes; Colombia Fil: Fajardo, R.. Universidad de los Andes; Colombia Fil: Giraldo, L.. Universidad Nacional de Colombia; Colombia Fil: Sapag, Manuel Karim. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich"; Argentina

midline of the cerebral hemispheres was only partially developed (Fig 2b). The holoprosencephaly in this dog, together with the mandibular agenesis, ear abnormalities, aglossia and microstomia identify this anomaly as holoprosencephaly with otocephaly. This type of anomaly has been reported in human beings (Pauli and others 1983) and mice (Hide and others 2002). In the present case, the brain abnormalities corresponded to those reported for the semilobar-type holoprosencephaly in human beings, in which the cerebrum is rudimentary, and the interhemispheric posterior fissure may or may not be present, the olfactory tracts and bulb are absent and the corpus callosum is rudimentary (Cohen 2001, Blaas and others 2002). Since previous litters born to the same parents had contained some puppies with similar characteristics the authors consider it likely that the malformation was inherited in an autosomal recessive manner. Malformations in dogs are not frequently reported because breeders consider them to be a detriment; there is, thus, a deficiency in data on the pathologies that result from this type of anomaly. The present case could represent a biological model for searching for genes associated with a holoprosencephaly-otocephaly complex in dogs. Currently, genes like Otx2, Prx1 and Prx2, which participate in the regulation of craniofacial and cerebra development, are candidates, as mutations in these genes cause holoprosencephaly and otocephaly in mice (Morsli and others 1999, Berge and others 2001, Hide and others 2002). The identification of genes associated with such abnormalities could help to identify carriers of recessive mutations, so that they are not used for breeding.

Prolonged, ambulatory monitoring of esophageal pH is important in the management of patients with atypical or refractory GERD. Traditionally, transnasal catheters are used to monitor esophageal pH, but patient comfort and modification of diet and activity may influence test reliability. TheBravopHmonitoring system (Medtronic Inc., Shoreview, Minn) is a catheter-free radiotelemetric antimony pH capsule that is attached to the esophageal mucosa. The capsule is connected to a delivery system that is designed for transoral, transnasal, or endoscopic attachment. This device is comparable to the conventional catheter system and studies have demonstrated patient tolerability with minimal complications. This is a report of an esophageal perforation that occurred during placement of the Bravo pH catheter delivery system.

Objectives In persons with spinal cord injury (SCI), several studies have shown that large bowel transit is decreased at the level of the left colon and rectum, and that postprandial colonic response to food is absent. To define these parameters further, the effects of food on colonic motility in persons with SCI were studied and compared to those of spinally intact (SI) individuals. Methods The study was conducted in eight subjects with SCI (four paraplegic and four quadriplegic) and six age-matched SI subjects. After routine bowel preparation, colonoscopy was performed with the proximal end of a solid state pressure transducer catheter (four sensors each separated by 10 cm) tethered to the splenic flexure using endoclips (Olympus). The subjects were then allowed to carry out their usual daily activities. Two phases were compared: 1 h before breakfast, designated as the “resting phase,” and 1 h during breakfast, designated as the “food-ingestion phase.” Results Baseline colonic activity of the SCI group was significantly less than in SI subjects. During meals, the motility index, mean amplitude of the waves, percent activity, and number of waves was significantly less in the SCI group. In both the SI and SCI groups, a postprandial colonic response was observed. However, in the SCI group, the response was seen only in the descending colon and not in the rectosigmoid region. Conclusions SCI decreases colonic motility, and this alteration may relate to difficulty with evacuation. The postprandial colonic response in SCI is present but is suboptimal and confined to the descending colon.

This work reports on the formation and characterization of a novel hydrogel based on the polysaccharide alginate physically crosslinked by calcium ions (Ca2+) in the presence of chondroitin sulfate (CS). Swelling data and morphological analysis showed that the alginate–Ca2+/CS hydrogel has a clear pH-dependent behavior. Compression tests revealed a gradual decrease in the elastic moduli (E) as the pH of hydrogel-immersed solution is raised but a pronounced decrease for the samples swelled at pH 8 was observed. This fact was attributed to a complete disruption of the polymer network. On the other hand, the hydrogel matrix remains stable when immersed in acidic media. In vitro drug release studies were performed in simulated gastric and intestinal fluids and the collected data showed that the hydrogels formed in this work respond to external stimuli (changes in pH) and, thus, present great potential to be applied in a colon-specific drug delivery system.

AIM: To investigate the presence or absence of high amplitude propagating contractions (HAPC), as well as the other measures of colonic motility, in persons with spinal cord injury (SCI). METHODS: Prolonged colonic ambulatory manometric studies were performed on 14 male volunteers: 8 with SCI (mean age, 59 ± 13 years; mean duration of injury, 13 ± 4 years) and 6 healthy able-bodied controls (mean age, 57 ± 10 years). A solid-state manometry catheter was endoscopically clipped to the splenic flexure. Recording was performed for > 24 h after manometric catheter placement. RESULTS: HAPC were absent in individuals with SCI during pre-sleep, sleep, and post-sleep phases. HAPC were significantly increased after awakening in non-SCI controls (0.8 ± 0.2 HAPC/h vs 10.5 ± 2.0 HAPC/h, P < 0.005). The motility index was lower in those with SCI than in controls pre- and post-sleep (SCI vs non-SCI: Pre-sleep, 2.4 ± 0.4 vs 8.8 ± 1.9, P < 0.01; Post-sleep, 4.3 ± 0.8 vs 16.5 ± 4.5, P < 0.05). However, a sleep-induced depression of colonic motility was observed in both the SCI and non-SCI groups (Pre-sleep vs Sleep, non-SCI: 8.8 ± 1.9 vs 2.1 ± 0.9, P < 0.002; SCI: 2.4 ± 0.4 vs 0.2 ± 0.03, P < 0.001), with the motility index of those with SCI during sleep not significantly different than that of the controls. CONCLUSION: HAPC were not observed in individuals with SCI pre- or post-sleep. A sleep-induced depression in general colonic motility was evident in SCI and control subjects.

Difficulty with evacuation (DWE) is common in individuals with spinal cord injury (SCI). Numerous studies have concluded that constipation, impaction, and incontinence cause significant morbidity and, collectively, constitute an important quality-of-life issue in individuals with SCI. Colonic motor activity was assessed using a solid-state manometry probe. We report here that colonic pressure activity is depressed during sleep compared to that observed in able-bodied controls. In addition, pressure activity was decreased during sleep compared to pre-sleep and post-sleep. We suspect that this may contribute to delayed colon transit time after SCI. In addition, since contraction of the abdominal wall musculature plays a role in normal defecation, we assessed whether an abdominal belt with implanted electrodes would improve DWE. In this respect, we demonstrated that neuromuscular stimulation of the abdominal wall improves a number of indices of defecatory function, including time to first stool and total bowel care time.

Background:. Motor activity of the colon during sleep is relatively quiescent but bursts of activity are observed during periods of arousal and when sleep is completed. However, it is not known how sleep alters the colonic motility of parsons with SCI. We thus studied the effect of sleep on the colonic motility of subjects with SCI and compared it with that in persons who were spinally intact (SI). Method£ The study was conducted on 8 subjects with SCI (mean age of 59 years, mean duration of injury of 17 years, 4 paraplegics, 4 quadriplegies), and 6 SI subjects (mean age 57 years). SCI subjects all complained of difficulty with evacuation (DWE) at least once in 6 months preceding the study; all received bowel care at least three/ week. After routine bowel preparation with lavage solution or Phosphosoda, colonoscopy was performed (all subjects had normal examinations). After colonoacopy, the proximal end of a solid-state pressure transducer catheter (4 sensors each separated by 10 cme.) was tethered to the splenic flexure using endoclips (Olympus Corp.) The subjects ware then allowed to carry out their usual daily activities, including sleep. Data from the catheter was recorded on a Gaeltec portable recorder. After compl~on of the study (which lasted 24 hours), the data was uploaded to a desktop computer for analysis. Significance of the difference between groups was evaluated by Student's T-test. Result. During sleep, the motility index was significantly lower in subjects with SCI than the SI (1.5 vs. 5.8, p

El astrocitoma es una neoplasia primaria del sistema nervioso central que se puede presentar en los animales; de las especies domésticas se ha observado con mayor frecuencia en los perros, de éstos, la edad y la raza son factores que influyen en su presentación, en estudios anteriores han descrito que el astrocitoma es una neoplasia que se presenta con mayor frecuencia en perros de características braquicefalicas, además que su malignidad depende de la localización y del carácter invasivo que presenta. Se presenta el estudio de caso de un paciente canino Labrador, macho de 6 años de edad, con un cuadro clínico neurológico de origen compresivo y obstructivo, derivado de una neoplasia intracraneala. Se documentó el caso a través del método clínico, basado en la historia clínica y la evolución del caso, imagenología e histopatología. Lo observado a través de las placas, correspondieron a una masa tumoral en la región ventral correspondiente al diencéfalo cuya localización se refiere adyacente a la estructura hipotalámica con efecto obstructivo y compresivo compatible con un astrocitoma; al estudio anatomopatológico se observo un tumor localizado adyacente al hipotálamo del cerebro; histológicamente el tumor se identifico como un astrocitoma gemistocítico.