777 Changing Student Perceptions of Surgical Careers

Aim

Increasing student interest in pursuing a surgical career at an undergraduate level.

Background

Data suggests that interest in surgical specialties may be declining, even from as early on as medical school. However, studies suggest that engagement with extra-curricular activities influences their likelihood to pursue surgical careers. Our study aimed to assess changes in student perception towards surgical careers following participation in a three-week surgical course.

Method

Students on placement at St Peter’s Hospital, Chertsey were invited to a course of 3 one-hour sessions covering practical surgical skills and lectures. Participants were tutored by Foundation-Year-Two doctors, with oversight of a surgical clinical teaching fellow and senior consultant. Students completed pre- and post-course surveys focusing on surgical interest, surgical skill confidence, placement-participation, and career preparation. The course was delivered through two cycles.

Results

Cycle one showed statistically significant improvements in suturing-confidence (mean increase 4.05 out of 10, p = 0.001), confidence in hand-ties (3.63 out of 10, p = 0.015) and understanding of developing a surgical portfolio (mean increase 1.95 out of 10, p = 0.005). After a second cycle, including the introduction of a surgical portfolio development lecture, students demonstrated a statistically significant improvement in mean scores across all areas. Notably, interest in pursuing a surgical career increased from mean 5.85/10 to 8.8/10 (p = 0.028).

Conclusions

We demonstrate that a short and easily accessible course can significantly improve student interest and understanding of a surgical career; equipping them with fundamental skills to pursue engagement at the undergraduate level.

204 A Systematic Review of Clinical Outcomes for Outpatient vs Inpatient Shoulder Arthroplasty

Aim

Outpatient shoulder arthroplasty is growing in popularity as a cost-effective and potentially equally safe alternative to inpatient arthroplasty. We investigated literature relating to outpatient shoulder arthroplasty, looking at clinical outcomes, complications, readmission, and cost compared to inpatient arthroplasty.

Method

We systematically searched Medline, Embase, PubMed using relevant search terms. Methodological quality of included studies was assessed using Methodological Index for Non-Randomised Studies score.

Results

We included 17 studies in our review with 11 included in the meta-analyses. A meta-analysis of hospital readmissions demonstrated that there was no statistically significant difference between outpatient and inpatient cohorts (OR = 0.89, 95% CI: 0.63-1.25, p = 0.49, I2=56%). Pooling results for all post-operative complications identified decreased complications in those undergoing outpatient surgery (OR = 0.70; 95% CI: 0.52-0.94, p = 0.02, I2=50%). No statistically significant difference was identified with respect to medical complications (OR = 0.86, 95% CI: 0.74-1.01, p = 0.07, I2=0%) or surgical complications (OR = 0.71, 95% CI: 0.45-1.12, p = 0.14, I2=26%). Considerable cost saving of between $3 614 – $53 202 (19.7 – 69.9%) per patient were present in the outpatient setting.

Conclusions

Shoulder arthroplasty in the outpatient setting is as safe as shoulder arthroplasty in the inpatient setting, with a significant reduction in cost. There is no demonstrable statistically significant difference with regards to readmissions between outpatient and inpatient shoulder arthroplasty. In the appropriately selected patient, outpatient shoulder arthroplasty is safe and cost-effective; however, we still need to work towards understanding who the appropriate patients are for this post-operative care pathway.

Lymphangioma of the jejunal mesentery and jejunal polyps presenting as an acute abdomen in a teenager

Cystic lymphangioma of the small bowel mesentery is a rare clinical entity, especially after childhood. Medical literature reveals a limited number of such cases presenting as acute abdomen due to bowel obstruction, small bowel volvulus and bleeding into the tumour. We present the management experience of an 18-year-old woman who presented with rapid onset diffuse peritonism and raised inflammatory markers. Computed tomography showed a mass in the small bowel mesentery with suspicion of segmental bowel ischaemia. Emergency laparotomy revealed a mass in the mid-jejunal mesentery close to the bowel wall with no bowel ischaemia. The patient made an uncomplicated recovery after segmental bowel resection and end-to-end anastomosis. Histology confirmed the mass as a cystic lymphangioma involving the jejunal mesentery and two small jejunal polyps. Lymphangioma could be considered in the differential diagnosis of an acute abdomen in a young adult when the presentation is atypical.

Solution, Solid, and Gas Phase Studies on a Nickel Dithiolene System: Spectator Metal and Reactor Ligand

The syntheses of cationic nickel complexes using N,N'-dimethyl piperazine 2,3-dithione (Me2Dt(0)) and N,N'-diisopropyl piperazine 2,3-dithione ((i)Pr2Dt(0)) ligands are reported. These ligands were used in synthesizing bis and tris(dithione)Ni(II) complexes as tetrafluoroborate or hexafluorophosphate salts, i.e., [Ni((i)Pr2Dt(0))2][BF4]2 ([1a][BF4]2), [Ni((i)Pr2Dt(0))2][PF6]2 ([1a][PF6]2), [Ni(Me2Dt(0))2][BF4]2 ([1b][BF4]2), [Ni((i)Pr2Dt(0))3][BF4]2 ([2a][BF4]2), and [Ni((i)Pr2Dt(0))3][PF6]2 ([2a][PF6]2), respectively. Complex [2a][PF6]2 was isolated from a methanolic solution of [1a][PF6]2. Compound [1a][BF4]2 crystallizes in a trigonal crystal system (space group, P31/c) and exhibits unique packing features, whereas [2a][BF4]2 crystallizes in a monoclinic (P21/n) space group. Cyclic voltammograms of [1a][BF4]2 and [1b][BF4]2 are indicative of four reduction processes associated with stepwise single-electron reduction of the ligands. Spectroelectrochemical experiments on [1a][BF4]2 exhibit an intervalence charge transfer (IVCT) transition as a spectroscopic signature of the mixed-valence [Ni((i)Pr2Dt(0))((i)Pr2Dt(1-))](-) species. Analysis of this IVCT band suggests that this ligand based mixed valence complex, [Ni((i)Pr2Dt(0))((i)Pr2Dt(1-))](-), behaves more like a traditional class II/III metal based mixed-valence complex. The density functional theory (DFT) and time dependent DFT calculations provide a theoretical framework for understanding the electronic structures and the nature of excited states of the target compounds that are consistent with their spectroscopic and redox properties. Vibrational spectra of [1a](2+) and [2a](2+) were investigated as discrete species in the gas phase using infrared multiple photon dissociation (IRMPD) spectroscopy.

Defensin like peptide from Panulirus argus relates structurally with beta defensin from vertebrates

Naturally occurring antimicrobial peptides take place in the first line of host defense against pathogen as part of the humoral innate immune response. β-defensins are among the most abundant antimicrobial peptides in mammals, and thought to be solely found in vertebrates until a recent report describing the cloning and sequencing of defensin like peptides in the spiny lobster Panulirus japonicus. In the current study, we cloned and sequenced two genes from the hemocytes of the spiny lobster Panulirus argus encoding for two isoforms of defensin-like peptides, thus confirming the presence of this protein in the Panulirus genus. The 44 amino acids mature peptides showed the conservation of cysteine pattern characterizing the β-defensins, as well as known amino acids residues critical to exert their antimicrobial activity. They are also amphipathics, hydrophobics, and display an overall positive charge (+1) located at the C-terminus. The tertiary structure obtained by homology modeling indicated that likely conformations of lobster peptides are highly similar to β-defensins from vertebrates. The phylogenetic study carried out by probabilistic methods confirmed the relation with ancestral β-defensin from vertebrates. The finding of a putative defensin-like peptide in the expressed sequence tag (EST) of the lobster Homarus americanus with high homology with those of P. argus described in this study, would indicate the presence of this peptides in Palinuridae family. Taking into account all similarities between these peptides with β-defensins from vertebrates, it is conceivable to further support the finding of a new family of β-defensins in invertebrate.

A Valence Bond Description of Dizwitterionic Dithiolene Character in an Oxomolybdenum-bis(dithione)

Metallo-dithiolene non-innocence is explored in an oxomolybdenum-bis(dithione) complex, [Mo⁴⁺O(i-Pr₂Pipdt)₂Cl][PF₆] (where i-Pr₂Pipdt is N,N'-piperazine-2,3-dithione), that possesses a piperazine ring as an integral part of the dithiolene ligand. The title complex displays unusual spectroscopic features for a formally reduced Mo(IV) dithiolene complex, namely a low energy metal-to-ligand charge transfer band with appreciable intensity and C-C and C-S stretching frequencies that are markedly different from those of oxomolydenum complexes coordinated to dianionic dithiolene ligands. The electronic structure of the ligand has been described in valence bond terms as a resonance hybrid of dithione and dizwitterionic dithiolene contributing structures.

Chiasma frequency is region specific and chromosome conformation dependent in a rye chromosome added to wheat

In many plant species synapsis starts at, or close to, the chromosome ends and this has been considered to be related to the distal location of chiasmata. In this regard we have studied the meiotic behavior of rye chromosome pair 5R in a wheat background using fluorescence in situ hybridization. The use of different DNA probes allowed the identification of the 2 rye homologues, their centromeres and subtelomeric heterochromatic chromomeres, and the telomeres of all chromosomes in prophase I and metaphase I. Three types of plants were analyzed: homozygotes for the standard chromosome 5R, homozygotes for a deficient chromosome 5R (del5R) with only the proximal 30% of its long arm (del5RL) and heterozygotes. Synapsis of the deficient chromosome arm pair del5RL was completed in most meiocytes at pachytene but the number of chiasmata formed was much lower than in the intact 5RL arm. Deletion facilitated the migration of the telomere of the accompanying chromosome arm 5RS during bouquet organization. This was followed by an increase of synapsis and chiasma frequency in this arm with regard to its counterpart of the intact chromosome. Results demonstrate that crossover formation depends on the DNA sequence or the chromatin organization of each chromosome region and that homologous alignment, synapsis and chiasma formation may be conditioned by chromosome conformation.

Treatment of acne with oral isotretinoin in patients with cystic fibrosis

BACKGROUND

Theoretical concerns about liver disease and vitamin A deficiency have limited the use of oral isotretinoin for troublesome acne in adolescents with cystic fibrosis.

METHODS

Oral isotretinoin was administered to nine patients with cystic fibrosis who had troublesome acne unresponsive to antibiotics. All patients were followed for 1-4 years after cessation of treatment.

RESULTS

Isotretinoin treatment cleared active acne lesions in all patients. It was well tolerated, and no patient had significant side effects. All nine patients were pleased or delighted with the improvement in their skin.

CONCLUSIONS

Adolescents with cystic fibrosis and acne can be treated with oral isotretinoin. Oral isotretinoin should be considered for adolescents with cystic fibrosis who have acne associated with scarring, acne not clearing with topical and antibiotic treatment, acne associated with depression or severe cystic acne.

Synthesis, characterization and structure of a low coordinate desoxomolybdenum cluster stabilized by a dithione ligand

Using an oxidized state of a dithiolene ligand, diisopropylpiperazine-2,3-dithione (i-Pr(2)Pipdt), two monooxo-molybdenum complexes have been synthesized. From one of them, a desoxomolybdenum cluster, [(i-Pr(2)Pipdt)Mo](4)[BF(4)](4) has been prepared. The molecular structure of this cluster reveals metal-metal interactions and weak coordination by the BF(4) anion.

Phenoloxidase activity in the hemolymph of the spiny lobster Panulirus argus

The prophenoloxidase activating system plays a major role in the defense mechanism of arthropods. In the present study, the phenoloxidase activity and its location in the hemolymph of the spiny lobster Panulirus argus is presented. Phenoloxidase activity was observed in the hemocyte lysate supernatant (HLS) and plasma after their incubation with trypsin. Higher amounts of trypsin were required to activate the HLS prophenoloxidase, due to the presence of a trypsin inhibitor in this fraction. Activation of prophenoloxidase was found when HLS was incubated with calcium, with an optimal pH between 7.5 and 8. This spontaneous activity is due to the prophenoloxidase activating enzyme, a serine proteinase that activates the prophenoloxidase once calcium ions were available. SDS was able to induce phenoloxidase activity in plasma and hemocyte fractions. Prophenoloxidase from HLS occurs as an aggregate of 300kDa. Electrophoretic studies combining SDS-PAGE and native PAGE indicate that different proteins produced the phenoloxidase activity found in HLS and plasma. Thus, as in most crustaceans, Panulirus argus contains a prophenoloxidase activating system in its hemocyte, comprising at least the prophenoloxidase activating enzyme and the prophenoloxidase. Finally, it is suggested that phenoloxidase activity found in plasma is produced by hemocyanin.

Synthesis, molecular and electronic structure, and TDDFT and TDDFT-PCM study of the solvatochromic properties of (Me2Pipdt)Mo(CO)4 complex (Me2Pipdt = N,N'-dimethylpiperazine-2,3-dithione)

The synthesis, spectroscopic, and structural characterization of the (Me2Pipdt)Mo(CO)4 complex (Me2Pipdt = N,N'-piperazine-2,3-dithione) are presented in this paper. The title complex crystallizes in the P2(1)/n space group with a = 25.541(3) A, b = 10.3936(14) A, c = 10.9012(12) A, beta = 92.261(9) degrees , V = 2891.6(6) A(3), and Z = 8. Gas- and solution-phase structural and electronic features of (Me2Pipdt)Mo(CO)4 and Me2Pipdt have been investigated using density functional theory. The molecular structure underscores the flexibility of the NC(S)C(S)N fragment in both the free ligand and the metal complex. On the basis of structural, spectroscopic, and theoretical results, the bidentate ligand in (Me2Pipdt)Mo(CO)4 is considered to be in the dithione, not dithiolate, form. Time-dependent density functional theory has been used for the investigation of the excited states and solvatochromic properties of (Me2Pipdt)Mo(CO)4. The calculated vertical excitation energies in solution are consistent with the experimental data, showing that the metal-to-ligand charge-transfer transitions, in both the visible and UV regions, dominate over the ligand-based pi-pi transitions.

Biotransformation of 3-nitro-4-hydroxybenzene arsonic acid (roxarsone) and release of inorganic arsenic by Clostridium species

The extensive use of 3-nitro-4-hydroxybenzene arsonic acid (roxarsone) in the production of broiler chickens can lead to increased soil arsenic concentration and arsenic contaminated dust. While roxarsone is the dominant arsenic species in fresh litter, inorganic As (V) predominates in composted litter. Microbial activity has been implicated as the cause, but neither the specific processes nor the organisms have been identified. Here we demonstrate the rapid biotransformation of roxarsone under anaerobic conditions by Clostridium species in chicken litter enrichments and a pure culture of a fresh water arsenate respiring species (Clostridium sp. strain OhILAs). The main products were 3-amino-4-hydroxybenzene arsonic acid and inorganic arsenic. Growth experiments and genomic analysis indicate strain OhILAs may use roxarsone as a terminal electron acceptor for anaerobic respiration. Electronic structure analysis suggests that the reducing equivalents should go to the nitro group, while liberation of inorganic arsenic from the intact benzene ring by cleaving the C-As bond is unlikely. Clostridium and Lactobacillus species are common in the chicken cecum and litter. Thus, the organic-rich manure and anaerobic conditions typically associated with composting provide the conditions necessary for the native microbial populations to transform the roxarsone in the litter releasing the more toxic inorganic arsenic.

Physical and genetic mapping of amplified fragment length polymorphisms and the leaf rust resistance Lr3 gene on chromosome 6BL of wheat

The Argentinian wheat cultivar Sinvalocho MA carries the Lr3 gene for leaf rust resistance on distal chromosome 6BL. In this cultivar, 33 spontaneous susceptible lines were isolated and cytogenetically characterized by C-banding. The analysis revealed deletions on chromosome 6BL in most lines. One line was nulli-6B, two lines were ditelo 6BS, two, three, and ten lines had long terminal deletions of 40, 30, and 20%, respectively, three lines showed very small terminal deletions, and one line had an intercalary deletion of 11%. Physical mapping of 55 amplified fragment length polymorphism (AFLP) markers detected differences between deletions and led to the division of 6BL into seven bins delimited by deletion breakpoints. The most distal bin, with a length smaller than 5% of 6BL, contained 22 AFLP markers and the Lr3 gene. Polymorphism for nine AFLPs between Sinvalocho MA and the rust leaf susceptible cultivar Gamma 6 was used to construct a linkage map of Lr3. This gene is at a genetic distance of 0.9 cM from a group of seven closely linked AFLPs. The location of the gene in a high recombinogenic region indicated a physical distance of approximately 1 Mb to the markers.

Chromosome structure of Triticum timopheevii relative to T. turgidum

The chromosome structure of four different wild populations and a cultivated line of Triticum timopheevii (2n = 28, AtAtGG) relative to Triticum turgidum (2n = 28, AABB) was studied, using genomic in situ hybridisation (GISH) and C-banding analysis of meiotic configurations in interspecific hybrids. Two wild accessions and the cultivated line showed the standard C-banding karyotype. The other two accessions are homozygous for translocation 5At/3G and translocations 1G/2G and 5G/6G. GISH analysis revealed that all the T. timopheevii accessions carry intergenome translocations 6At/1G and 1G/4G and identified the position of the breakpoint in translocation 5At/3G. C-banding analysis of pairing at metaphase I in the hybrids with T. turgidum provides evidence that four species-specific translocations (6AtS/1GS, 1GS/4GS, 4GS/4AtL, and 4AtL/3AtL) exist in T. timopheevii, and that T. timopheevii and T. turgidum differ in the pericentric inversion of chromosome 4A. Bridge plus acentric fragment configurations involving 4AL and 4AtL were identified in cells at anaphase I. This result suggests that the paracentric inversion of 4AL from T. turgidum does not exist in T. timopheevii. Both tetraploid species have undergone independent and distinct evolutionary chromosomal rearrangements. The position, intercalary or subdistal, of the breakpoints in species-specific translocations and inversions contrasts with the position, at or close to the centromere, of intraspecific translocations. Different mechanisms for intraspecific and species-specific chromosome rearrangements are suggested.

Chromosome structure of Triticum timopheevii relative to T. turgidum

The chromosome structure of four different wild populations and a cultivated line of Triticum timopheevii (2n = 28, AtAtGG) relative to Triticum turgidum (2n = 28, AABB) was studied, using genomic in situ hybridisation (GISH) and C-banding analysis of meiotic configurations in interspecific hybrids. Two wild accessions and the cultivated line showed the standard C-banding karyotype. The other two accessions are homozygous for translocation 5At/3G and translocations 1G/2G and 5G/6G. GISH analysis revealed that all the T. timopheevii accessions carry intergenome translocations 6At/1G and 1G/4G and identified the position of the breakpoint in translocation 5At/3G. C-banding analysis of pairing at metaphase I in the hybrids with T. turgidum provides evidence that four species-specific translocations (6AtS/1GS, 1GS/4GS, 4GS/4AtL, and 4AtL/3AtL) exist in T. timopheevii, and that T. timopheevii and T. turgidum differ in the pericentric inversion of chromosome 4A. Bridge plus acentric fragment configurations involving 4AL and 4AtL were identified in cells at anaphase I. This result suggests that the paracentric inversion of 4AL from T. turgidum does not exist in T. timopheevii. Both tetraploid species have undergone independent and distinct evolutionary chromosomal rearrangements. The position, intercalary or subdistal, of the breakpoints in species-specific translocations and inversions contrasts with the position, at or close to the centromere, of intraspecific translocations. Different mechanisms for intraspecific and species-specific chromosome rearrangements are suggested.Key words: Triticum timopheevii, chromosome pairing, translocation, evolution, C-banding, GISH.

Pairing affinities of the B- and G-genome chromosomes of polyploid wheats with those of Aegilops speltoides

Chromosome pairing at metaphase I was studied in different interspecific hybrids involving Aegilops speltoides (SS) and polyploid wheats Triticum timopheevii (AtAtGG), T. turgidum (AABB), and T. aestivum (AABBDD) to study the relationships between the S, G, and B genomes. Individual chromosomes and their arms were identified by means of C-banding. Pairing between chromosomes of the G and S genomes in T. timopheevii x Ae. speltoides (AtGS) hybrids reached a frequency much higher than pairing between chromosomes of the B and S genomes in T. turgidum x Ae. speltoides (ABS) hybrids and T. aestivum x Ae. speltoides (ABDS) hybrids, and pairing between B- and G-genome chromosomes in T. turgidum x T. timopheevii (AAtBG) hybrids or T. aestivum x T. timopheevii (AAtBGD) hybrids. These results support a higher degree of closeness of the G and S genomes to each other than to the B genome. Such relationships are consistent with independent origins of tetraploid wheats T. turgidum and T. timopheevii and with a more recent formation of the timopheevi lineage.

Growth hormone receptor mutations in children with idiopathic short stature

Homozygous or compound heterozygous mutations in the GH receptor (GHR) gene result in GH insensitivity syndrome. Previous reports have shown that some heterozygous mutations may induce a partial insensitivity to GH, but others appear to have limited effect on growth. To investigate further these observations, we analyzed the GHR gene in 17 subjects with idiopathic short stature (ISS). All subjects had a height 2 SD or more below the mean and/or abnormal growth velocity. In addition, serum GH levels were 10 ng/mL or more and insulin-like growth factor I levels were normal or low. A novel heterozygous mutation resulting in a valine to isoleucine change (V144I) in exon 6 in the extracellular domain was found in one subject. His mother and one brother had significant short stature and also had the identical mutation. Affected family members also had a polymorphism in exon 6 of the GHR gene, which has been present in other subjects who had short stature and heterozygous mutations of the GHR gene. The other subjects with ISS had normal GHR genes. However, eight subjects had neutral polymorphisms distributed throughout the GHR locus. Accumulating evidence suggests that GHR gene mutations account for up to 5% of all ISS patients. These mutations should be considered when other causes of short stature have been eliminated.

Clinical, biochemical, and molecular investigations of a genetic isolate of growth hormone insensitivity (Laron's syndrome)

We have characterized the GH receptor mutation that is responsible for extreme short stature and GH insensitivity in a Bahamian genetic isolate. Heights of affected individuals ranged from -4.0 to -6.3 SD. Like others with Laron's syndrome, they had normal to high serum GH concentrations and low serum insulin-like growth factor I concentrations. Circulating levels of GH-binding protein activity were below limits of detection. Amplification of exons 2-7 and screening with single strand conformational polymorphism analysis located an abnormality in exon 7. Sequencing identified homozygosity for a C to T transition in the third position of codon 236. Reverse transcription and PCR amplification of complementary DNA from lymphocytes showed that this same sense mutation generated a new splice donor site 63 bp 5' to the normal exon 7 splice site. This novel site was used to the exclusion of the normal site in homozygotes. Both normal and variant messenger ribonucleic acid species were detected in heterozygotes. The predicted protein lacks 21 amino acids, including those defining the WS-like motif of the GH receptor extracellular domain. The high frequency of Laron's syndrome in this isolated island population probably reflects the introduction of the G236 splice mutation by a settler early in the 300-yr history of English settlement.

[Angiotensin II-acetylcholine interaction on the mechanical response of the isolated rat stomach]

This research was carried on denervated isolated rat stomach. Mechanical response to Ach treated with three different ATN II concentrations was recorded. No competitive antagonism was observed so that no common receptor can be supposed. The apparent noncompetitive antagonism may be ascribed to the action of ATN II on P and T Ca++ activating systems.

Comparison of etidocaine and lidocaine for obstetrical analgesia

Etidocaine, a relatively new local anaesthetic agent, is compared with lidocaine for use in epidural anaesthesia for vaginal delivery. The parameters compared were quality of anaesthesia, dose of drug, onset and regression of sensory blockade, complete degree of motor blockade, effect on maternal blood pressure, and foetal Apgar scores at one and five minutes. The major differences between the drugs are the lower percentage of satisfactory anaesthesia with etidocaine, the much greater variability in the time of onset of complete sensory block with etidocaine as compared to lidocaine, the more profound motor block with etidocaine, and the slightly longer duration of action of this drug. It is concluded that etidocaine has no real place in epidural anaesthesia for obstetrics.