Radiologic assessment of gastric emptying of water-soluble contrast media: New data security from a longitudinal study. / Evaluación radiológica del vaciamiento gástrico de medio de contraste hidrosoluble: nuevos datos de seguridad de un estudio longitudinal.

BACKGROUND AND OBJECTIVES: Practice guidelines for preoperative fasting have not clearly established the fasting time needed after oral administration of water-soluble contrast media. The aim of this study was to determine the time required for the gastric emptying during the water-soluble contrast media in patients with acute abdominal pain. METHODS: This prospective longitudinal study included sixty-eight patients older than 18 years of age with acute abdominal pain, who required a water-soluble contrast media enhanced abdominal computed tomography study. Plain radiographs were obtained hourly until complete the gastric emptying. Patients with probable bowel obstruction were not included in the study. RESULTS: A total of 31 (45,6%), 54 (79,4%), and 64 (94,1%) patients achieved a complete gastric clearance of barium in 1, 2 and 3 hours, respectively. All patients achieved complete emptying of water-soluble contrast media within 6 hours. Gastric emptying time was not associated with gender (P=0,44), body mass index (P=.35), fasting time prior to water-soluble contrast media intake (P=0,12), administration of opioids in the emergency room (P=0,7), and the presence of comorbidities (P=0,36). CONCLUSION: Ninety-four percent of the patients with acute abdominal pain achieved complete gastric emptying within 3hours after the administration of water-soluble contrast media. All of them achieved complete gastric emptying within 6hours. The results suggested 6hours after oral intake of the contrast media is enough to complete transit of water-soluble contrast media through the stomach and avoid unnecessary risks.

Anesthetic management of two parturients with cerebral palsy and prior selective dorsal rhizotomy.

Selective dorsal rhizotomy is a surgical spine procedure used to reduce spasticity in patients with upper motor neuron dysfunction caused by conditions such as cerebral palsy. The optimal anesthetic approach for obstetric patients who have undergone a selective dorsal rhizotomy is unknown. The use and efficacy of neuraxial anesthesia in these patients has not been described. We describe the use of neuraxial anesthesia in two patients with prior selective dorsal rhizotomy. Unless contraindicated for other reasons, a neuraxial anesthetic approach appears to be an effective option in patients with a history of a selective dorsal rhizotomy.

Anesthetic management of parturients with pre-existing paraplegia or tetraplegia: a case series.

With improvements in management and rehabilitation, more women with spinal cord injury are conceiving children. Physiologic manifestations of spinal cord injury can complicate anesthetic management during labor and delivery. Patients who delivered at Mayo Clinic, Rochester, Minnesota between January 1, 2001 and May 31, 2012 with a history of traumatic spinal cord injury were identified via electronic record search of all parturients. Eight patients undergoing nine deliveries were identified. Six deliveries (67%) among five patients (63%) involved a trial of labor. Among these deliveries, three (50%) occurred vaginally, all with successful epidural analgesia. Trial of labor failed in the remaining three patients, and required cesarean delivery facilitated via epidural (n=1), spinal (n=1) and general anesthesia (n=1). Three patients (33%) underwent scheduled cesarean delivery via epidural (n=1), spinal (n=1), and general anesthesia (n=1). Four patients having five deliveries had a history of autonomic hyperreflexia before pregnancy. One patient had symptoms during pregnancy, two patients had episodes during labor and delivery, and three patients described symptoms in the immediate postpartum period. These symptoms were not reported by any patient without a history of autonomic hyperreflexia. Neuraxial labor analgesia may have a higher failure rate in patients with spinal cord injury, possibly related to the presence of Harrington rods. Postpartum exacerbations of autonomic hyperreflexia are common in patients with a history of the disorder.

Patient fear of anesthesia complications according to surgical type: potential impact on informed consent for anesthesia.

BACKGROUND: Past research has explored patients' expectations about the informed consent process. However, it is currently unknown if the complexity of the surgical procedure influences the type of anesthesia-related risks that patients wish disclosed. This study explored fears of anesthesia-related complications and whether these changed based on severity of surgery classification. METHODS: Patients presenting to our pre-operative evaluation clinic from February 2013 to May 2013 were asked to participate in a survey-based study meant to evaluate their perception of five possible anesthetic risks (peripheral nerve injury, death, nausea and vomiting, heart attack and stroke) when confronted with differing levels of surgical severity. RESULTS: One thousand surveys were administered, and 894 were returned for an overall response rate of 89%. Fear of death was the greatest concern as compared to the other risk factors independent of the severity of surgery. The level of fear for all risk factors, with the exception of stroke and heart attack, were dependent on the severity of surgery. Fear of death decreased as the severity of surgery decreased (major 46%, moderate 38%, minor 25%). For major surgery, the fear of perioperative death differed significantly with age (P < 0.001); specifically, with increasing age came a lessened fear of death. CONCLUSION: Awareness by anesthesia providers of those fears that patients report may allow for a more personalized approach to providing information that may better allay anxiety. Further, these results may better tailor the informed consent process to one that meets particular patient concerns.

Patient perspectives on informed consent for anaesthesia and surgery: American attitudes.

BACKGROUND: Principles of informed consent are ethically, morally, and legally grounded in physicians' responsibility to patients. This study examined patient expectations regarding the informed consent during the perioperative process, specifically risk information exchange, preferred method and timing of delivery, and the roles that patient anxiety and understanding might play. METHODS: Five hundred patients seen in our pre-operative clinic were surveyed by written questionnaire. Patients were asked about their level of agreement with a number of statements pertaining to informed consent and their preferences for discussion of types of risks. Anxiety concerns, impact of ability to understand complexities of care, preferences for timing, and method of presentation were assessed. RESULTS: Four hundred eleven of 500 surveys (82%) were completed. A majority of respondents (92% and 80%, respectively) believed the risk of common but less consequential complications and rare yet severe complications should be discussed. Only 21% agreed that anxiety generated by discussion of risks outweighed benefit and only 6% agreed that discussion of risks should be restricted based on patient inability to appreciate complexities of care. Discussion was preferred on the day of surgery, 1 week before, and 1 month before in 46%, 35%, and 16% of respondents, respectively, and independent of level of anxiety generated by such discussion (P = 0.87). Respondents preferred discussion with their anaesthesia provider alone (44%) or in combination with written information (52%) as compared with written information only (4%) (P < 0.01). CONCLUSIONS: Greater awareness of patient preferences and expectations may result in better information exchange between anaesthesia providers and their patients.

Low temperature growth, freezing survival, and production of antifreeze protein by the plant growth promoting rhizobacterium Pseudomonas putida GR12-2.

The plant growth promoting rhizobacterium Pseudomonas putida GR12-2 was originally isolated from the rhizosphere of plants growing in the Canadian High Arctic. Here we report that this bacterium was able to grow and promote root elongation of both spring and winter canola at 5 degrees C, a temperature at which only a relatively small number of bacteria are able to proliferate and function. In addition, the bacterium survived exposure to freezing temperatures, i.e., -20 and -50 degrees C. In an effort to determine the mechanistic basis for this behaviour, it was discovered that following growth at 5 degrees C, P. putida GR12-2 synthesized and secreted to the growth medium a protein with antifreeze activity. Analysis of the spent growth medium, following concentration by ultrafiltration, by SDS-polyacrylamide gel electrophoresis revealed the presence of one major protein with a molecular mass of approximately 32-34 kDa and a number of minor proteins. However, at this point it is not known which of these proteins contains the antifreeze activity.

Characterization of Eimeria tenella unsporulated oocyst-specific cDNA clones.

A cDNA library was constructed with poly(A)+ RNA from unsporulated oocysts of Eimeria tenella in pUC18. After screening, 4 cDNA clones that hybridized to RNA of unsporulated and sporulating oocysts but not to RNA of either sporulated oocysts or second generation merozoites were isolated and characterized. Each of the cDNA clones is unique. The loci for 2 of the clones are on E. tenella chromosome 7, the site of the third is located on chromosome 6 and the last clone hybridizes, for the most part, to chromosome 5 but also to other E. tenella chromosomes. The cognate RNAs for each of the cDNA clones show differential patterns of hybridization during oocyst sporulation with the levels of RNA being low at the start of sporulation (0 hr), increasing to peak levels between 6.5 and 23 hr after the onset of sporulation and, in each case, decreasing to low hybridization levels at 48 hr after initiation of sporulation. These results establish that specific mRNA levels are differentially regulated during sporulation.

Proteins of the vitreous humor during experimentally induced myopia.

Significant myopia was evident within 14 days after a translucent goggle was placed over the eye of a newly hatched chick. This myopia was characterized by large negative refractive error, increased axial and equatorial eye lengths, and increased wet eye weight. The volume of the vitreous humor increased in the myopic eye, because of a signficant accumulation of liquid vitreous humor. The protein concentration of the vitreous humor of the myopic and nonmyopic eyes was greater at day 14 than at day 0 (ie, first day after hatching). Moreover, over this time, the protein concentration in the liquid component decreased, whereas the protein concentration in the gel component increased in both myopic and nonmyopic eyes. No difference was found in the protein concentrations between the myopic and nonmyopic eye at day 14. Polyacrylamide gel electrophoresis revealed changes in band position and intensity of individual protein compoents between days 0 and 14. No major differences were found in the gel or the liquid vitreous humor between the myopic and the nonmyopic eyes. Comparison of vitreous humor proteins with proteins from the plasma showed that some but not all of the proteins in the vitreous had the same apparent molecular masses as proteins from these sources.

A complete cDNA for adenine phosphoribosyltransferase from Arabidopsis thaliana.

An intact cDNA from Arabidopsis thaliana for adenine phosphoribosyltransferase (APRT) was isolated and sequenced. The cDNA is 729 nucleotides in length and predicts a protein of Mr 27,140. The deduced amino acid sequence has been compared with those of other APRTs and shown to be most similar to the Escherichia coli protein. Construction of a molecular tree of the known APRT amino acid sequences indicates the A. thaliana and E. coli APRT sequences form one cluster and the currently available vertebrate and invertebrate sequences form a separate grouping. Since it is possible to select either for or against the expression of APRT, the isolation of this APRT cDNA clone will allow these selection schemes to be used in plant genetic experiments.

Comparison of regulatory and structural regions of the Xenopus laevis small heat-shock protein-encoding gene family.

We have isolated several unique Xenopus laevis hsp30 (encoding heat-shock protein 30) genomic clones, one of which contains two complete hsp30 genes (hsp30C and hsp30D), as well as the promoter and N-terminal coding region of a third gene (hsp30E). Nucleotide sequence and restriction enzyme analysis revealed that this gene cluster is different from a cluster isolated previously. The hsp30C and hsp30D genes encode proteins of approx. 24 kDa. In all, the hsp30 gene family contains a minimum of seven genes. The strand exchange and breakage of the duplication events which generated this gene family appear to have occurred within tracts of DNA which potentially can assume a Z-DNA conformation. Comparing the amino acid (aa) sequences of each known Hsp30 protein with bovine alpha-crystallin revealed a high degree of shared conservation of aa that constitute the major structural feature(s) of alpha-crystallin.

Eimeria spp. of the domestic fowl: resolution of chromosomes by field inversion gel electrophoresis.

The molecular karyotypes of five species of chicken coccidia, viz., Eimeria acervulina, E. brunetti, E. maxima, E. necatrix, and E. tenella, were determined using field inversion gel electrophoresis (FIGE). Each species has a distinctive set of resolvable chromosomes which range from about 1 to greater than 5.7 megabases. We were able to resolve at least 8 chromosomes for E. acervulina, 5 for E. brunetti, 10 for E. maxima, 6 for E. necatrix, and 9 for E. tenella. If the value of 67 megabases for the genomic DNA of E. tenella is accurate, then under the conditions used here only about 60% of its chromosomal complement has been resolved.

Development and enhancement of agricultural biotechnology in some countries in Latin America.

A number of research institutions and both local and international agencles in Latin America are using biotechnology as part of an effort to enhance agricultural productivity. However, it is very much an open question as to whether all of these various organizations can provide the best means of realizing this goal. Latin American countries vary dramatically in their knowledge base and current use of modern biotechnology. Thus, while some countries lack the ability to develop, or possibly even implement, many aspects of modern biotechnology, others are quite advanced in this regard. This review provides a somewhat selective overview of current research in the area of agricultural biotechnology in Mexico, Costa Rica and Ecuador, with emphasis on how the existing agencies and institutions have responded to the challenge of biotechnology. In addition, general strategies for the development of agricultural biotechnology in these countries are presented and discussed.

DNA sequence analysis of endoglucanase genes from Pseudomonas fluorescens subsp. cellulosa and Pseudomonas sp. NCIB 8634.

The DNA of two previously isolated recombinant clones, one from Pseudomonas sp. NCIB 8634 (= Cellvibrio mixtus) (pPC71) and another from Pseudomonas fluorescens subsp. cellulosa (pPFC4) that express endoglucanase activity in E. coli was sequenced. Plasmid pPC71 had three open reading frames, two of which include portions of plasmid pBR322. The third open reading frame occurs entirely within the Pseudomonas DNA insert and encodes a protein with a molecular mass of 5845 Da. The DNA insert in pPFC4 was found to contain an open reading frame (PFC-ORF) that encodes a protein of 32189 Da. The major endoglucanase produced in E. coli cells carrying pPFC4 is about 30,000 Da. It is concluded that PFC-ORF encodes this endoglucanase. Both ribosome and catabolite gene activator protein binding sites lie upstream from the initiating codon of PFC-ORF. An interesting feature of the PFC-ORF protein is the presence of amino acid motifs Val-Ser-Ser-Ser-Ser and Val-Val-Ser-Ser-Ser-Ser-Ser that occur within a 25 amino acid span.

Genomic arrangement of repeated PS700 elements in the nematode Panagrellus silusiae.

When genomic DNA from the free-living nematode Panagrellus silusiae is digested with the restriction endonuclease BamHI and separated by electrophoresis, a band in the 700 base pair size range is evident after ethidium bromide staining. One of the 0.7-kilobase fragments (PS700-1) was characterized and found to be a member of a moderately repetitive DNA family (T. Warren and J.J. Pasternak. 1988. Nucleic Acids Res. 16: 10,833-10,847). In the current study, DNA sequence analyses of three independently isolated copies of the PS700 DNA family showed the same nucleotide sequence and greater than 98% similarity to PS700-1. Four EMBL-4 bacteriophage clones were isolated from a Panagrellus genomic DNA library with PS700-1 as the probe and were analyzed by restriction endonuclease site mapping and Southern blot DNA hybridization. These clones contain 31 copies of the PS700 DNA family. In each case, the units are arranged in head-to-tail arrays. One of the EMBL-4 clones contains copies of a novel variant of the PS700 elements. The maintenance of both nucleotide sequence and restriction endonuclease restriction site homogeneity among members of the dispersed PS700 DNA family may denote a functional role for these sequences.

Isolation, characterization and manipulation of cellulase genes.

The complete hydrolysis of cellulose requires a number of different enzymes including endoglucanase, exoglucanase and beta-glucosidase. These enzymes function in concert as part of a 'cellulase'complex called a cellulosome. In order (i) to develop a better understanding of the biochemical nature of the cellulase complex as well as the genetic regulation of its integral components and (ii) to utilize cellulases either as purified enzymes or as part of an engineered organism for a variety of purposes, researchers have, as a first step, used recombinant DNA technology to isolate the genes for these enzymes from a variety of organisms. This review provides some perspective on the current status of the isolation, characterization and manipulation of cellulase genes and specifically discusses (i) strategies for the isolation of endoglucanase, exoglucanase and beta-glucosidase genes; (ii) DNA sequence characterization of the cellulase genes and their accompanying regulatory elements; (iii) the expression of cellulase genes in heterologous host organisms and (iv) some of the proposed uses for isolated cellulase genes.

A related moderately repetitive DNA family in the nematodes Ascaris lumbricoides and Panagrellus silusiae.

Digestion of genomic DNA from the nematodes Panagrellus silusiae and Ascaris lumbricoides with restriction endonuclease BamH1 releases a 0.7 kilobase (kb) fragment. The 0.7 kb fragment from both nematodes was cloned onto E. coli plasmid pUC19. Using representative clones as DNA hybridization probes, it was found that (i) the BamH1 fragments cross-hybridize; (ii) a ladder-effect with multiples of 0.7 kb was evident in both species after hybridization to genomic DNA and (iii) the genomic copy number of BamH1 elements is 150 and 195 for P. silusiae and A. lumbricoides respectively. DNA sequence analysis of the inserts, AL700-1 and PS700-1, revealed nucleotide blocks with over 85% similarity. No open reading frames are present in either DNA fragment. Neither fragment hybridizes to genomic DNA from Caenorhabditis elegans. Northern blot hybridization indicated that the 0.7 kb element is transcribed into poly(A)(-)-RNA in P. silusiae; but, is not transcribed in adult Ascaris muscle. Thus, P. silusiae and A. lumbricoides share a homologous, tandemly arrayed, moderately repetitive DNA family.

Ascaris lumbricoides: zonal localization of immunoreactive collagen in the cuticle.

Monoclonal antibodies that were raised against cuticular components from the free-living nematode Panagrellus silusiae were found to react with a cuticular collagenous domain from Ascaris lumbricoides. One of these monoclonal antibodies was used to localize the collagenous epitope within sectioned Ascaris cuticles. By indirect immunofluorescence, accessible binding sites were observed in the basal zone of the cuticle. Immunological staining occurred in the innermost lamella of the basal zone, i.e., basal lamella, in which the fibrillar palisade gave a strong response. The three layers of the spiral fiber system of the basal zone exhibited a distinctive immunofluorescence pattern. In each of these layers, irregular shaped blocks, often quadrangular, were immunostained; whereas, adjacent blocks were immunonegative. Immunostaining was, for the most part, absent from the cortical and medial zones of the cuticle as well as from other tissues within the worm.

Experimentally induced myopia in chicks: morphometric and biochemical analysis during the first 14 days after hatching.

Application of a translucent goggle over the chick eye on the first day after hatching led to the development of myopia. By the 14th day, the mean refractive error was about -10.0 D. Significant increases in axial and equatorial diameters were observed when the treated eyes were compared with untreated contralateral eyes. The lens did not appear to be affected, either optically or biochemically. A temporal study showed that changes were evident within 2 days of goggle application, and were significantly established 5 days later. Total soluble protein concentrations of the treated and untreated eyes were not significantly different, nor were the dry weights of the sclera and cornea. The enlargement of the eyeball that was observed in the experimental induction of myopia seems due to an increase in fluid within the eye. The data are consistent with the view that refractive properties of the chick eye are dependent upon the clarity of the visual image and modulation of these features occurs after hatching.

Microbial DNA diagnostic technology.

The principle objectives when creating a robust DNA diagnostic assay system are sensitivity, specificity and minimal read-time. To meet these ends, depending on the specifically defined test, various aspects of molecular hybridization methodology must be optimized. In particular, among other things, attention has focused on (i) formulating highly specific probes; (ii) devising sensitive nonisotopic detection systems, (iii) minimizing the extent of preparing clinical samples for assaying, (iv) amplifying the target sequence to augment sensitivity and (v) enhancing hybridization kinetics to speed up the reaction period. In this article, some recent studies that are directed to the development of nucleic acid hybridization systems for clinical diagnosis of microorganisms are considered.

Isolation of Endoglucanase Genes from Pseudomonas fluorescens subsp. cellulosa and a Pseudomonas sp.

Endoglucanase genes from Pseudomonas fluorescens subsp. cellulosa and Pseudomonas sp. were cloned and characterized. DNA hybridization studies showed that these genes are homologous and that each species has one copy of the gene per genome. The DNA fragment from Pseudomonas sp. codes for, at most, a 23-kilodalton endoglucanase.