Imagining and constraining ferrovolcanic eruptions and landscapes through large-scale experiments.

Ferrovolcanism, yet to be directly observed, is the most exotic and poorly understood predicted manifestation of planetary volcanism. Large-scale experiments carried out at the Syracuse Lava Project offer insight into the emplacement dynamics of metallic flows as well as coeval metallic and silicate flows. Here, we find that, under the same environmental conditions, higher-density/lower-viscosity metallic lava moves ten times faster than lower-density/higher-viscosity silicate lava. The overall morphology of the silicate flow is not significantly affected by the co-emplacement of a metallic flow. Rather, the metallic flow is largely decoupled from the silicate flow, occurring mainly in braided channels underneath the silicate flow and as low-relief breakouts from the silicate flow front. Turbulent interactions at the metallic-silicate flow interface result in mingling of the two liquids, preserved as erosional surfaces and sharp contacts. The results have important implications for the interpretation of possible ferrovolcanic landscapes across our solar system.

Functional characterization of the S. cerevisiae genome by gene deletion and parallel analysis.

The functions of many open reading frames (ORFs) identified in genome-sequencing projects are unknown. New, whole-genome approaches are required to systematically determine their function. A total of 6925 Saccharomyces cerevisiae strains were constructed, by a high-throughput strategy, each with a precise deletion of one of 2026 ORFs (more than one-third of the ORFs in the genome). Of the deleted ORFs, 17 percent were essential for viability in rich medium. The phenotypes of more than 500 deletion strains were assayed in parallel. Of the deletion strains, 40 percent showed quantitative growth defects in either rich or minimal medium.

Production of chick germline chimeras from fluorescence-activated cell-sorted gonocytes.

Modification of the chicken germline has been difficult, because it has been challenging to fractionate sufficient numbers of primordial germ cells for manipulation and implantation into developing embryos. A technique to enrich cell suspensions for primordial germ cells, using fluorescence-activated cell sorting (FACS), has recently been developed. The objective of the current study was to demonstrate that the FACS-enriched early embryonic gonocytes could fully participate in development of the germline. Therefore, cells were disassociated from stage 27 gonads, incubated with mouse anti-stage-specific embryonic antigen-1, which was detected with goat-antimouse IgM-fluorescein isothiocyanate, and the fluorescently labeled cells were sorted from the unlabeled cells using FACS. The isolated gonocyte population was injected into the blastoderm of unincubated stage X embryos, the germinal crescent of 3-d embryos, and into the circulation of stage 17 embryos that were pretreated with busulfan. Barred Plymouth Rock gonocytes were implanted exclusively into recipient White Leghorn embryos, and White Leghorn gonocytes were implanted exclusively into Barred Plymouth Rock recipient embryos. Embryos were cultured until hatch, and male putative chimeras were reared to sexual maturity. Germline chimerism was evaluated by observing feather color of the progeny. All injection methods resulted in germline chimeras demonstrating that FACS-sorted gonocytes can fully participate in development. Moreover, it was demonstrated that gonocytes isolated from stage 27 embryonic gonads can be introduced into embryos at an earlier stage of development, and the introduced gonocytes can fully participate in germline development.

Clinical outcomes of proximal row carpectomy versus four-corner arthrodesis for post-traumatic wrist arthropathy: a systematic review.

We conducted a systematic review of studies reporting clinical outcomes after proximal row carpectomy or to four-corner arthrodesis for scaphoid non-union advanced collapse or scapholunate advanced collapse arthritis. Seven studies (Levels I-III; 240 patients, 242 wrists) were evaluated. Significantly different post-operative values were as follows for four-corner arthrodesis versus proximal row carpectomy groups: wrist extension, 39 (SD 11º) versus 43 (SD 11º); wrist flexion, 32 (SD 10º) versus 36 (SD 11º); flexion-extension arc, 62 (SD 14º) versus 75 (SD 10º); radial deviation, 14 (SD 5º) versus 10 (SD 5º); hand grip strength as a percentage of contralateral side, 74% (SD 13) versus 67% (SD 16); overall complication rate, 29% versus 14%. The most common post-operative complications were non-union (grouped incidence, 7%) after four-corner arthrodesis and synovitis and clinically significant oedema (3.1%) after proximal row carpectomy. Radial deviation and post-operative hand grip strength (as a percentage of the contralateral side) were significantly better after four-corner arthrodesis. Four-corner arthrodesis gave significantly greater post-operative radial deviation and grip strength as a percentage of the opposite side. Wrist flexion, extension, and the flexion-extension arc were better after proximal row carpectomy, which also had a lower overall complication rate.

Mass-murdering: deletion of twenty-three ORFs from Saccharomyces cerevisiae chromosome XI reveals five genes essential for growth and three genes conferring detectable mutant phenotype.

In the frame of the European Network for Functional Analysis (EUROFAN), two regions from chromosome XI covering 54kb have been subjected to 'mass-murder'. Ten deletions covering 23 novel open reading frames (ORFs) were constructed in haploid and diploid strains. Six deletions were lethal in haploid strains. One deletion caused slow germination of spores and slow cellular growth, and another one was associated with both cellular growth thermosensitivity and poor growth on glycerol. These two defects were assigned to two different genes. All mutant phenotypes were complemented by a single gene, enabling us to identify five genes essential for vegetative growth, three genes with detectable phenotype and 15 dispensable genes under standard physiological conditions.

A ring-enlarged oxetanocin A analogue as an inhibitor of HIV infectivity.

Two ring-expanded analogues (compounds 2 and 3) of the anti-HIV fermentation product oxetanocin A (1) were synthesized from commercially available diacetone D-glucose. Antiviral testing against HIV in ATH8 cells revealed that the ring-expanded analogue 2 possessed a similar activity profile as oxetanocin A. Neither compound, however, was capable of providing full protection to the cells against HIV infection. The isomeric ring-expanded analogue 3 was totally devoid of anti-HIV activity. Molecular modeling suggested that while oxetanocin A and compounds 2 and 3 share a large common substructure with the potent anti-HIV drug, dideoxyadenosine (ddA), the extra hydroxymethyl substituent may contribute negatively to the binding of these molecules to a critical enzyme. The negative contribution may be less important in oxetanocin and isomer 2 than in isomer 3. From these studies it would appear that both oxetane and tetrahydrofuran rings are equivalent templates to support the adenine base in terms of anti-HIV activity.

Arytenoid vocal shunt in laryngectomized patients.

A method is presented for forming short, mucosa-lined vocal shunt in cases of supracricoid laryngectomy with preservation of one or two arytenoids, or the interarytenoid fold alone. On the basis of radiologic and particularly radiocinematographic examinationion of the anterior pharyngeal wall is of paramount importance. In cases of complete absence of leakage, said wall lies in the plane of the arytenoids or somewhat posteriorly. After simple supracricoid laryngectomy it is possible to prevent aspiration also by translocation of the anterior pharyngeal wall into the plane of the cricoid cartilage plate. The clinical experience with this supracricoid shunt is still scanty. Of 25 cases with the arytenoid vocal shunt, phonation was possible in 22 cases under the expiratory pressure of 20-45 cm H2O; in one under the more elevated pressure, and in the last two the result is still not known. Loudness of speech was 70-100 db and its comprehensibility 73-90 percent. Complete absence of leakage was observed in 17 cases, "practical" prevention of aspiration (some drops of thin fluids, no saliva) in seven cases, profuse leakage in one case (ceased after correction), In the last 10 consecutive cases the problem of aspiration was completely eliminated. Advantages and disadvantages of our own method in comparison with Asai's method have been presented.

Diagnosis of acute bacterial osteomyelitis of the pubis by means of fine needle aspiration.

Fine needle aspiration (FNA) was used to make a definitive diagnosis of osteomyelitis of the pubis with negligible trauma to an elderly patient. The material obtained was adequate to resolve the differential diagnosis of osteomyelitis versus osteitis pubis occurring after urologic surgery. The three basic components of acute bacterial osteomyelitis, an acute inflammatory cell exudate of neutrophils, necrotic bone and bacteria in cells, were present in the FNA smears and cell blocks; the presence of bacteria was shown by Gram staining of FNA smears and culture of part of the FNA specimen.

[The course of the oropharyngeal stage of deglutition in physiological condition. Computer topokinetic analysis of videofluoroscopic images]. / Przebieg fazy gardlowej aktu polykania w warunkach fizjologicznych. Komputerowa analiza topokinetyczna obrazów rentgenokinematograficznych.

The performed analysis covers the physiology of the pharyngeal phase of deglutition in 11 patients aged 45-65 years. The studies were carried out with the aid of roentgenocinematographic examinations (RTGC) and after preparing an adequate computer program, a computer topokinetic analysis was accomplished (CTA). The measurement of parameters established in CTA make it possible to obtain the image of the pathway passed by the anatomical structures, the dynamics, the shape and the relative distances of two anatomical structures, with the duration of the deglutition act being taken into consideration. The use of RTGC images in CTA allows for better understanding of the mechanism acting in the pharyngeal phase of deglutition act in physiological conditions.

[Disorders of the pharyngeal stage of deglutition after classical and extended supraglottic laryngectomies. Computerized tomographic analysis of x-ray images]. / Zaburzenia fazy gardlowej aktu polykania po laryngektomiach nadglosniowych klasycznych i poszerzonych. Komputerowa analiza topokinetyczna obrazów rentgenokinematograficznych.

In 20 patients with laryngeal cancers, of both sexes and aged from 17 to 76 years, a partly classical or extended supraglottic laryngectomy was performed. The accomplished roentgenocinematographic analysis dealt with the disorders of the pharyngeal phase of deglutition act (RTGC). Next, by selecting characteristic schemas of frames for individual phases of deglutition, a computerized topokinetic analysis was carried out (CTA). The deglutition disorders were estimated in relation to the spared anatomical structures, formation of glosso-laryngeal recesses after this type of operations as well as leakage of contrast medium into the trachea.

[Mechanisms smoothing deglutition disorders after oral cancer surgery]. / Mechanizmy lagodzace zaburzenia polykania po wycieciu nowotworu jamy ustnej.

Compensatory treatment for oropharyngeal dysphagia includes postural changes and reducing the risk of aspiration. Some of compensatory maneuvers are introduced spontaneously by the ill at first weeks after oral cavity tumour resection. On the basis of roentgenotelevision examination of deglutition in 82 patients we detected mechanisms with intention to minimize swallowing disturbances. Variability of their occurrence and differences in their efficiency should be emphasized, as well as essential synchronization of laryngeal closure with emptying of pharynx and opening upper oesophageal sphincter for swallowing efficiency. The valuation of compensatory maneuvers introduced spontaneously by the ill was defined as an important part of swallowing rehabilitation.

[Compensatory mechanisms of food transmission and lower respiratory tract protection after classical and extended supraglottic laryngectomies. Computerized topokinetic analysis of roentgen-cinematographic images]. / Mechanizmy kompensacyjne przewodzenia pokarmów i ochrony dolnych dróg oddechowych po klasycznych i poszerzonych laryngektomiach nadglosniowych. Komputerowa analiza topokinetyczna obrazów rentgenokinematograficznych.

Studies were performed on 22 patients, aged from 17 to 78 years, in whom, owing to laryngeal cancers, partly classical or extended supraglottic laryngectomy was carried out. The evaluation involving the pharyngeal deglutition course was accomplished by resorting to computerized topokinetic analysis of the roentgen-cinematographic images. The completed observation revealed good mobility of the anatomical structures participating in deglutition, small volume and number of glossolaryngeal recesses. There were few patients in whom the contrast medium passed to the trachea. Better passage of food as well as protection of lower respiratory tract were associated with the improvement of parameters facilitating the deglutition.