Application of project-based service-learning courses in medical education: trials of curriculum designs during the pandemic

BACKGROUND

Due to COVID-19, face-to-face service activities in service-learning courses have become unfeasible. To address this challenge, this study aims to integrate project-based learning into medical education's service-learning curriculum. This study also seeks to evaluate the effectiveness of this instructional approach and identify factors that influence its success.

METHODS

A total of 135 first-year medical students enrolled in a mandatory 1-credit service-learning course were recruited. The course involved various service activities aligned with the needs of the local community. The students were organized into 12 groups, each working on different service-learning projects, such as raising health awareness or educating the public about specific diseases. Following the completion of the course, a questionnaire was distributed among the students to gather feedback on the course, and 122 (valid responses were collected, representing a response rate of 90.3%).

RESULTS

The results indicated that the project-based service-learning course significantly improved students' "interpersonal communication skills," their ability to "learn and grow from work," and their sense of "professionalism" (all p ≤ 0.037). Among the various aspects of service learning, the highest agreement was observed for "executing the project," followed by "group discussions and project formulation," "overall course review," "review of project outcomes," "outcome presentations," "teaching proposal writing and project brainstorming," "sharing of service-learning experiences by teachers," and "sharing of service-learning experiences by teaching assistants." Students also found certain factors to be beneficial in enhancing the learning effectiveness of service-learning courses, including "prize money for service-learning outcomes," "funding for service-learning activities," and "consultations from medical personnel" (all p ≤ 0.01). However, "course credit" and "photography software" did not show significant effects (both p > 0.05). The most preferred resources or activities for future service-learning courses were "course credit" and "face-to-face service-learning activities."

CONCLUSIONS

The project-based learning method improved the learning effectiveness in service-learning courses. Students perceived that the number of course credits reflects the course value and plays a pivotal role in enhancing the learning effectiveness in service-learning courses. During the epidemic, students still expect to have face-to-face service activities in service-learning courses. Therefore, without the impact of the epidemic, service learning courses should return to face-to-face service activities.

Molecular Relationships in Biofilm Formation and the Biosynthesis of Exoproducts in Pseudoalteromonas spp

Most members of the Pseudoalteromonas genus have been isolated from living surfaces as members of epiphytic and epizooic microbiomes on marine macroorganisms. Commonly Pseudoalteromonas isolates are reported as a source of bioactive exoproducts, i.e., secondary metabolites, such as exopolymeric substances and extracellular enzymes. The experimental conditions for the production of these agents are commonly associated with sessile metabolic states such as biofilms or liquid cultures in the stationary growth phase. Despite this, the molecular mechanisms that connect biofilm formation and the biosynthesis of exoproducts in Pseudoalteromonas isolates have rarely been mentioned in the literature. This review compiles empirical evidence about exoproduct biosynthesis conditions and molecular mechanisms that regulate sessile metabolic states in Pseudoalteromonas species, to provide a comprehensive perspective on the regulatory convergences that generate the recurrent coexistence of both phenomena in this bacterial genus. This synthesis aims to provide perspectives on the extent of this phenomenon for the optimization of bioprospection studies and biotechnology processes based on these bacteria.

Labeled oxytocin administered via the intranasal route reaches the brain in rhesus macaques

Oxytocin may have promise as a treatment for neuropsychiatric disorders. Its therapeutic effect may depend on its ability to enter the brain and bind to the oxytocin receptor. To date, the brain tissue penetrance of intranasal oxytocin has not been demonstrated. In this nonhuman primate study, we administer deuterated oxytocin intranasally and intravenously to rhesus macaques and measure, with mass spectrometry, concentrations of labeled (exogenously administered) and endogenous oxytocin in 12 brain regions two hours after oxytocin administration. Labeled oxytocin is quantified after intranasal (not intravenous) administration in brain regions (orbitofrontal cortex, striatum, brainstem, and thalamus) that lie in the trajectories of the olfactory and trigeminal nerves. These results suggest that intranasal administration bypasses the blood-brain barrier, delivering oxytocin to specific brain regions, such as the striatum, where oxytocin acts to impact motivated behaviors. Further, high concentrations of endogenous oxytocin are in regions that overlap with projection fields of oxytocinergic neurons.

Ultrasonic drilling for the characterisation of building stones and salt induced decay

Historic stone buildings can experience severe decay through salt induced weathering. Decay can be easily seen with the eye but can also occur below the surface. Characterising the changes in the material's structural properties induced by weathering is essential for the evaluation of durability of the stone and for the decision on the best conservation strategy to maintain built heritage. Minimally invasive, in situ tools are needed to establish the location and state of decay at the site. Here an ultrasonic drilling tool is introduced with a specially manufactured tip to monitor subsurface properties of sandstones. Different types of sandstones with varying compressive strength are tested and an artificially weathered sample is investigated. The tool tip wear and exerted force on the drilled samples are evaluated and compared to conventional drilling. Ultrasonic drilling shows promising results for the use in conservation science to assess stone properties and decay.

Liquorice (Glycyrrhiza glabra): the journey of the sweet root from Mesopotamia to England

Liquorice is a very ancient plant widely used in the East for millennia. It has often been employed in sweets and confectionery and also for minor ailments including cough, constipation and dyspepsia. It was probably carried to Europe by the Cluniac order of monks. Then, almost by accident, it became established in West Yorkshire at Pontefract after the dissolution of the monasteries in the 1530s. Abuse of liquorice is not uncommon. It can occur in the anorexia/bulimia syndrome and also in the dangerous condition of pseudoaldosteronism, which is characterised by severe hypertension and hypokalaemia and can lead to death. Liquorice remains a useful sweetener for all sorts of confectionery, including sweets and cakes (together with beer and liqueurs).

Amanita muscaria (fly agaric): from a shamanistic hallucinogen to the search for acetylcholine

The mushroom Amanita muscaria (fly agaric) is widely distributed throughout continental Europe and the UK. Its common name suggests that it had been used to kill flies, until superseded by arsenic. The bioactive compounds occurring in the mushroom remained a mystery for long periods of time, but eventually four hallucinogens were isolated from the fungus: muscarine, muscimol, muscazone and ibotenic acid. The shamans of Eastern Siberia used the mushroom as an inebriant and a hallucinogen. In 1912, Henry Dale suggested that muscarine (or a closely related substance) was the transmitter at the parasympathetic nerve endings, where it would produce lacrimation, salivation, sweating, bronchoconstriction and increased intestinal motility. He and Otto Loewi eventually isolated the transmitter and showed that it was not muscarine but acetylcholine. The receptor is now known variously as cholinergic or muscarinic. From this basic knowledge, drugs such as pilocarpine (cholinergic) and ipratropium (anticholinergic) have been shown to be of value in glaucoma and diseases of the lungs, respectively.

Oxytocin receptor mRNA expression in dorsolateral prefrontal cortex in major psychiatric disorders: A human post-mortem study

There is growing interest in oxytocin as a putative treatment for various psychiatric disorders including major depressive disorder, bipolar disorder and schizophrenia/schizoaffective disorder. However, potential alterations in the endogenous brain oxytocin system in these disorders are poorly characterized. Brain expression of oxytocin and its receptor genes in patients with these psychiatric disorders has not been well studied outside the hypothalamus. We measured expression of mRNA for oxytocin and its receptor in the dorsolateral prefrontal cortex of postmortem brains using quantitative polymerase chain reaction in a total of 581 individuals. These individuals either were diagnosed with major depressive disorder (n = 135), bipolar disorder (n = 57), schizophrenia/schizoaffective disorder (n = 169), or were control subjects, defined as individuals with no lifetime history of any of these disorders (n = 220). Diagnoses of major depressive disorder and bipolar disorder were associated with significantly increased oxytocin receptor mRNA levels in the dorsolateral prefrontal cortex. This finding is discussed in light of the extant literature on the dysregulation of oxytocin signaling in individuals with major psychiatric disorders.

Genetic inhibition of neurotransmission reveals role of glutamatergic input to dopamine neurons in high-effort behavior

Midbrain dopamine neurons are crucial for many behavioral and cognitive functions. As the major excitatory input, glutamatergic afferents are important for control of the activity and plasticity of dopamine neurons. However, the role of glutamatergic input as a whole onto dopamine neurons remains unclear. Here we developed a mouse line in which glutamatergic inputs onto dopamine neurons are specifically impaired, and utilized this genetic model to directly test the role of glutamatergic inputs in dopamine-related functions. We found that while motor coordination and reward learning were largely unchanged, these animals showed prominent deficits in effort-related behavioral tasks. These results provide genetic evidence that glutamatergic transmission onto dopaminergic neurons underlies incentive motivation, a willingness to exert high levels of effort to obtain reinforcers, and have important implications for understanding the normal function of the midbrain dopamine system.

Rhubarb (Rheum species): the role of Edinburgh in its cultivation and development

Rhubarb was grown and used throughout China for thousands of years. It then found its way to St Petersburg where the Romanovs developed a flourishing trade in the plant to the rest of Europe. James Mounsey, a physician to the Tsar, brought back seeds from Russia to Scotland at considerable risk to himself. He passed some of the seeds to Alexander Dick and John Hope. Both these physicians then grew rhubarb at Prestonfield and the Botanic Garden (both in Edinburgh), respectively. Eventually rhubarb, in the form of Gregory's powder, became a common and popular medicine throughout the UK.

Correction: Genetic inhibition of neurotransmission reveals role of glutamatergic input to dopamine neurons in high-effort behavior

In Figure 1e and f, "F4 control" should be "Cre/tdTomato" and "F4Cre KO" should be "F4Cre/tdTomato". In addition, in the Figure1f legend, the first sentence should end with "(Cre/tdTomato: n = 10, F4Cre/tdTomato: n = 14)".In the 'Materials and Methods' section, under 'Electrophysiology,' the n values for evoked action potential recordings were omitted. The sentence 'For high-frequency stimulus-induced action potentials, the stimulus electrode was placed in the rostral part of VTA and a train of 100 Hz stimuli (1 s) was applied' should end with '(Cre/tdTomato: n=10, F4Cre/tdTomato: n=14).'Later in the same paragraph, in 'For recording evoked EPSCs (Cre/tdTomato, n=13, F4Cre/tdTomato, n=15; AMPA EPSCs were recorded at -70  mV and NMDA EPSCs were recorded at +40 mV)', the phrase 'Cre/tdTomato, n=13, F4Cre/tdTomato, n=15' should be deleted; those n values should have appeared at the end of the later sentence beginning 'Miniature ESPCs...'. The complete, corrected sentence is 'Miniature EPSCs (mEPSCs) were acquired in the presence of 0.5-1 μM TTX and 100 μM picrotoxin and semiautomatically detected by offline analysis using in-house software in Igor Pro (Wavemetrics, Portland, OR, USA) (Cre/tdTomato, n=13, F4Cre/tdTomato, n=15).'Finally, in the 'Materials and Methods' section, third sentence under 'Immunohistochemistry,' information for one TH antibody was omitted. The list of antibodies should end with 'or Millipore MAB5280, 1:1000-1:2000.'

ITR‑284 modulates cell differentiation in human chronic myelogenous leukemia K562 cells

ITR‑284 is a carboxamide analog that can inhibit proliferation in human promyelocytic leukemia HL-60 cells. To understand the effects and molecular mechanisms of ITR‑284 in human erythromyeloblastoid leukemia, we treated K562 cells with different concentrations of ITR‑284 (0, 2, 4, 6, 8 and 10 nM) and all-trans retinoic acid (ATRA) (0, 0.1, 0.5, 1, 5 and 10 µM) for 24 h. The IC50 of ITR‑284 was ~10 nM in K562 cells treated for 24 h as determined by MTT assay. May-Grünwald-Giemsa staining and nitro blue tetrazolium (NBT) assays were used to determine cell morphology changes and differentiation after ITR‑284 and ATRA treatment. In addition, mRNA expression levels of hematopoietic factors, including GATA‑1, NF-E2 and GATA‑2, were elevated, while expression levels of BCR‑ABL were downregulated in K562 cells after 24 h of treatment with ITR‑284 as determined by quantitative reverse transcription polymerase chain reaction. In addition, western blot analyses showed that FOXM1, GLI 1 and c-MYC protein levels were decreased by ITR‑284. Taken together, our data show that ITR‑284 induced K562 cell differentiation, which led to decreased tumorigenesis. Our findings suggest that ITR‑284 could be a potential candidate for treating chronic myelogenous leukemia.

YC-1 induces G0/G1 phase arrest and mitochondria-dependent apoptosis in cisplatin-resistant human oral cancer CAR cells

Oral cancer is a serious and fatal disease. Cisplatin is the first line of chemotherapeutic agent for oral cancer therapy. However, the development of drug resistance and severe side effects cause tremendous problems clinically. In this study, we investigated the pharmacologic mechanisms of YC-1 on cisplatin-resistant human oral cancer cell line, CAR. Our results indicated that YC-1 induced a concentration-dependent and time-dependent decrease in viability of CAR cells analyzed by MTT assay. Real-time image analysis of CAR cells by IncuCyte™ Kinetic Live Cell Imaging System demonstrated that YC-1 inhibited cell proliferation and reduced cell confluence in a time-dependent manner. Results from flow cytometric analysis revealed that YC-1 promoted G₀/G₁ phase arrest and provoked apoptosis in CAR cells. The effects of cell cycle arrest by YC-1 were further supported by up-regulation of p21 and down-regulation of cyclin A, D, E and CDK2 protein levels. TUNEL staining showed that YC-1 caused DNA fragmentation, a late stage feature of apoptosis. In addition, YC-1 increased the activities of caspase-9 and caspase-3, disrupted the mitochondrial membrane potential (AYm) and stimulated ROS production in CAR cells. The protein levels of cytochrome c, Bax and Bak were elevated while Bcl-2 protein expression was attenuated in YC-1-treated CAR cells. In summary, YC-1 suppressed the viability of cisplatin-resistant CAR cells through inhibiting cell proliferation, arresting cell cycle at G₀/G₁ phase and triggering mitochondria-mediated apoptosis. Our results provide evidences to support the potentially therapeutic application of YC-1 on fighting against drug resistant oral cancer in the future.

MicroRNA-30a-5p (miR-30a) regulates cell motility and EMT by directly targeting oncogenic TM4SF1 in colorectal cancer

PURPOSE

Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide, and many oncogenes and tumor suppressor genes are involved in CRC. MicroRNAs (miRNAs) are small non-coding RNAs that can negatively regulate gene expression. Previous studies have revealed that miRNAs regulate the development and progression of many cancers. In this study, we investigated the role of microRNA-30a-5p (miR-30a) in CRC and its unknown mechanisms.

METHODS

qRT-PCR was used to detect miR-30a and TM4SF1 mRNA expression in CRC specimens and cell lines. CRC cell migration and invasion were assessed after transfection with miR-30a or TM4SF1 using wound healing and trans-well migration and invasion assays. Transmembrane-4-L-six-family protein (TM4SF1) was validated as a target of miR-30a in CRC through luciferase reporter assay and bioinformatics algorithms. Moreover, two EMT regulators, E-cadherin and VEGF, were also identified using Western blotting and immunohistochemistry.

RESULTS

We found that miR-30a was down-regulated in CRC tumor tissues and cell lines, and miR-30a was inversely associated with advanced stage and lymph node metastatic status compared with normal tissues. miR-30a decreased migration and invasion in CRC cell lines, and miR-30a overexpression not only down-regulated TM4SF1 mRNA and protein expression, but also inhibited the expression of VEGF and enhanced expression of E-cadherin. We also showed that TM4SF1 was up-regulated in CRC tumor specimens compared with adjacent normal tissues, and TM4SF1 expression was significantly associated with advanced stage and lymph node status compared with adjacent normal tissues.

CONCLUSIONS

These results suggest that miR-30a is an important regulator of TM4SF1, VEGF, and E-cadherin for CRC lymph node metastasis, a potential new therapeutic target in CRC.

Cortactin is a prognostic marker for oral squamous cell carcinoma and its overexpression is involved in oral carcinogenesis

EMS1 (chromosome eleven, band q13, mammary tumor and squamous cell carcinoma-associated gene 1) gene amplification and the concomitant cortactin overexpression have been reported to associate with poor prognosis and tumor metastasis. In this study, we examined cortactin expression by immunohistochemistry in human oral tumors and murine tongue tumors which were induced by the carcinogen 4-nitroquinoline 1-oxide (4-NQO). The immunostaining results show over- to moderate expression of cortactin in 85% (104/122) of oral squamous cell carcinoma (OSCC) tissues and in all 15 leukoplakia tissues examined. Further, statistical analysis indicates that cortactin overexpression appears to be a predictor for shorter survival and poorer prognosis in OSCC patients. In an animal model, cortactin is shown to upregulate in infiltrating squamous cell carcinoma, papilloma, and epithelia with squamous hyperplasia, indicating that cortactin induction is an early event during oral carcinogenesis. It is suggested that cortactin expression is mediated in the progression of pre-malignancy to papilloma, based on earlier cortactin induction in pre-malignancy preceding cyclin D1 in papilloma. In conclusion, cortactin overexpression is frequently observed in human OSCC and mouse tongue tumors. Thus, cortactin may have an important role in the development of oral tumors in human and mice. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 799-812, 2017.

COMT Val(158) Met genotype is associated with reward learning: a replication study and meta-analysis

Identifying mechanisms through which individual differences in reward learning emerge offers an opportunity to understand both a fundamental form of adaptive responding as well as etiological pathways through which aberrant reward learning may contribute to maladaptive behaviors and psychopathology. One candidate mechanism through which individual differences in reward learning may emerge is variability in dopaminergic reinforcement signaling. A common functional polymorphism within the catechol-O-methyl transferase gene (COMT; rs4680, Val(158) Met) has been linked to reward learning, where homozygosity for the Met allele (linked to heightened prefrontal dopamine function and decreased dopamine synthesis in the midbrain) has been associated with relatively increased reward learning. Here, we used a probabilistic reward learning task to asses response bias, a behavioral form of reward learning, across three separate samples that were combined for analyses (age: 21.80 ± 3.95; n = 392; 268 female; European-American: n = 208). We replicate prior reports that COMT rs4680 Met allele homozygosity is associated with increased reward learning in European-American participants (β = 0.20, t = 2.75, P < 0.01; ΔR(2) = 0.04). Moreover, a meta-analysis of 4 studies, including the current one, confirmed the association between COMT rs4680 genotype and reward learning (95% CI -0.11 to -0.03; z = 3.2; P < 0.01). These results suggest that variability in dopamine signaling associated with COMT rs4680 influences individual differences in reward which may potentially contribute to psychopathology characterized by reward dysfunction.

CCY-1a-E2 induces G2/M phase arrest and apoptotic cell death in HL-60 leukemia cells through cyclin-dependent kinase 1 signaling and the mitochondria-dependent caspase pathway

Our previous study demonstrated that 2-[(3-methoxybenzyl)oxy]benzaldehyde (CCY-1a-E2) is a potent compound that acts against multiple human leukemia cell lines. CCY-1a-E2 was also shown to have efficacious anti‑leukemic activity in vivo. However, the molecular mechanism of action of CCY‑1a‑E2 attributed to its anticancer effect remains poorly understood. In the present study, CCY‑1a‑E2 suppressed cell viability in multiple leukemia cell lines (HL‑60, K562, KG‑1 and KG‑1a) via inhibition of cell proliferation, cell cycle arrest and induction of apoptosis. CCY‑1a‑E2 exhibited a marked toxic effect on HL‑60 cells and displayed low cytotoxicity in normal human peripheral blood mononuclear cells (PBMCs). Results from flow cytometric analysis indicated that CCY‑1a‑E2 promoted G2/M phase arrest and promoted apoptosis in the HL‑60 cells. CCY‑1a‑E2 treatment upregulated cyclin B, cyclin‑dependent kinase 1 (CDK1), cell division cycle 25C (cdc25C) and p21 protein expression. CCY‑1a‑E2 caused apoptotic cell death and DNA fragmentation as determined by 4',6‑diamidino‑2‑phenylindole (DAPI) staining and DNA gel electrophoresis. Elevated activities of caspase‑8, ‑9 and ‑3 were observed during CCY‑1a‑E2‑induced cell apoptosis; their specific inhibitors were found to block CCY‑1a‑E2‑induced apoptosis, respectively. Moreover, CCY‑1a‑E2 time‑dependently disrupted the mitochondrial membrane potential (ΔΨm), and it enhanced the protein levels of Fas/CD95, cytochrome c, Bax, cleaved PARP, as well as attenuated Bcl‑2 expression in the HL‑60 cells. Our results provide direct evidence that supports the future potential therapeutic application of CCY-1a-E2 in leukemia.

Purification of Cu/Zn superoxide dismutase from Piper betle leaf and its characterization in the oral cavity

The aim of this study was to purify protein(s) from Piper betle leaf for identification and further characterization. A functionally unknown protein was purified to apparent homogeneity with a molecular mass of 15.7 kDa and identified as Cu/Zn superoxide dismutase (SOD). The purified SOD appeared to be monomeric and converted to its dimeric form with increased enzymatic activity in betel nut oral extract. This irreversible conversion was mainly induced by slaked lime, resulting from the increase in pH of the oral cavity. Oral extract from chewing areca nut alone also induced SOD dimerization due to the presence of arginine. The enhanced activity of the SOD dimer was responsible for the continuous production of hydrogen peroxide in the oral cavity. Thus, SOD may contribute to oral carcinogenesis through the continuous formation of hydrogen peroxide in the oral cavity, in spite of its protective role against cancer in vivo.

A preliminary study suggests that nicotine and prefrontal dopamine affect cortico-striatal areas in smokers with performance feedback

Nicotine and tonic dopamine (DA) levels [as inferred by catechol-O-methyl tranferase (COMT) Val158Met genotype] interact to affect prefrontal processing. Prefrontal cortical areas are involved in response to performance feedback, which is impaired in smokers. We investigated whether there is a nicotine × COMT genotype interaction in brain circuitry during performance feedback of a reward task. We scanned 23 healthy smokers (10 Val/Val homozygotes, 13 Met allele carriers) during two fMRI sessions while subjects were wearing a nicotine or placebo patch. A significant nicotine × COMT genotype interaction for BOLD signal during performance feedback in cortico-striatal areas was seen. Activation in these areas during the nicotine patch condition was greater in Val/Val homozygotes and reduced in Met allele carriers. During negative performance feedback, the change in activation in error detection areas such as anterior cingulate cortex (ACC)/superior frontal gyrus on nicotine compared to placebo was greater in Val/Val homozygotes compared to Met allele carriers. With transdermal nicotine administration, Val/Val homozygotes showed greater activation with performance feedback in the dorsal striatum, area associated with habitual responding. In response to negative feedback, Val/Val homozygotes had greater activation in error detection areas, including the ACC, suggesting increased sensitivity to loss with nicotine exposure. Although these results are preliminary due to small sample size, they suggest a possible neurobiological mechanism underlying the clinical observation that Val/Val homozygotes, presumably with elevated COMT activity compared to Met allele carriers and therefore reduced prefrontal DA levels, have poorer outcomes with nicotine replacement therapy.

Inhibition of formyl peptide-stimulated phospholipase D activation by Fal-002-2 via blockade of the Arf6, RhoA and protein kinase C signaling pathways in rat neutrophils

Three recently developed selective phospholipase D (PLD) inhibitors N-(2-(4-(2-oxo-2,3-dihydro-1H-benzo[d]imidazol-1-yl)piperidin-1-yl)ethyl)-2-naphthamide (VU0155056), (S)-N-(1-(4-(5-chloro-2-oxo-2,3-dihydro-1H-benzo[d]imidazol-1-yl)piperidin-1-yl)propan-2-yl)-2-naphthamide (VU0155069), and N-(2-(4-oxo-1-phenyl-1,3,8-triazaspiro[4,5]decan-8-yl)ethyl)quinoline-3-carboxamide (VU0285655-1) inhibited O2 (•-) generation in formyl-Met-Leu-Phe (fMLP)-stimulated rat neutrophils. A novel 2-phenyl-4-quinolone compound 6-chloro-2-(2-chlorophenyl)-4-oxo-1,4-dihydroquinoline-3-carboxylate (Fal-002-2), which inhibited O2 (•-) generation, also reduced the fMLP- but not phorbol ester-stimulated PLD activity (IC50 16.0 ± 5.0 μM). Fal-002-2 attenuated the interaction of PLD1 with ADP-ribosylation factor (Arf) 6, Ras homology (Rho) A and protein kinase C (PKC) isoforms (α, βI, and βII), and also inhibited the membrane recruitment of Arf6 and RhoA in fMLP-stimulated neutrophils, but not in GTPγS-stimulated cell-free system. The cellular levels of GTP-bound Arf6 and GTP-bound RhoA were reduced by Fal-002-2. Fal-002-2 also attenuated the membrane recruitment of Rho-associated protein kinase 1, phosphorylation of myosin light chain 2 at Thr18/Ser19 and PLD1 at Thr147, and the interaction of Arf6 with both arfaptin 1 and phosphatidylinositol 4-phosphate 5-kinase 1A. The association between RhoA and Vav, the interaction of Vav with both Lyn and Lck, the membrane recruitment of Vav, and the phosphorylation of Vav at Tyr174, but not Src family at Tyr416, were all attenuated by Fal-002-2 in fMLP-stimulated neutrophils. These results indicate that Fal-002-2 is not a direct PLD inhibitor, but the inhibition of fMLP-stimulated PLD activity by Fal-002-2, which partly accounts for its suppression of O2 (•-) generation, is attributable to the blockade of both Arf6 and RhoA activation and attenuation of the interaction of Arf6, RhoA and PKC isoforms with PLD1 in rat neutrophils.

AKT serine/threonine protein kinase modulates baicalin-triggered autophagy in human bladder cancer T24 cells

Baicalin is one of the major compounds in the traditional Chinese medicinal herb from Scutellaria baicalensis Georgi. We investigated the molecular mechanisms of cell autophagy induced by baicalin in human bladder cancer T24 cells. Baicalin inhibited cell survival as shown by MTT assay and increased cell death by trypan blue exclusion assay in a concentration-dependent manner. Baicalin did not induce apoptotic cell death in T24 cells by TUNEL and caspase-3 activity assay. Baicalin induced the acidic vesicular organelle cell autophagy marker, manifested by acridine orange (AO) and monodansylcadaverine (MDC) staining and cleavage of microtubule-associated protein 1 light chain 3 (LC3). The protein expression levels of the Atg 5, Atg 7, Atg 12, Beclin-1 and LC3-II were upregulated in T24 cells after baicalin treatment. Inhibition of autophagy by 3-methyl-adenine (an inhibitor of class III phosphatidylinositol-3 kinase; 3-MA) reduced the cleavage of LC3 in T24 cells after baicalin treatment. Furthermore, protein expression levels of phospho-AKT (Ser473) and enzyme activity of AKT were downregulated in T24 cells after baicalin treatment. In conclusion, baicalin triggered cell autophagy through the AKT signaling pathway in T24 cells.

Inhibition of formyl peptide-stimulated superoxide anion generation by Fal-002-2 occurs mainly through the blockade of the p21-activated kinase and protein kinase C signaling pathways in ratneutrophils

In formyl-Met-Leu-Phe (fMLP)-stimulated rat neutrophils, a synthetic compound, 6-chloro-2-(2-chlorophenyl)-4-oxo-1,4-dihydroquinoline-3-carboxylate (Fal-002-2), inhibited superoxide anion (O2(•-)) generation with an IC50 value of about 11μM, which was not mediated by scavenging the generated O2(•-) or by a cytotoxic effect on neutrophils. Fal-002-2 effectively attenuated the phosphorylation of Ser residues in p47(phox) and the association between p47(phox) and p22(phox) in fMLP-stimulated neutrophils. The interaction of p47(phox) with protein kinase C (PKC) isoforms (α, βI, βII, δ and ζ) was attenuated by Fal-002-2 with a similar IC50 value to that required for inhibition of O2(•-) generation, whereas Fal-002-2 had no prominent effect on PKC isoform membrane translocation and did not affect the kinase activity. Moreover, Fal-002-2 had no effect on the phosphorylation of Akt and downstream glycogen synthase kinase-3β, only slightly affected the intracellular free Ca(2+) concentration, phosphorylation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase (MAPK), but effectively attenuated the downstream MAPK-activated protein kinase-2 phosphorylation. The interaction of p21-activated kinase (PAK) 1with p47(phox), phosphorylation of PAK1 (Thr423/Ser144) and the membrane recruitment of PAK1 were effectively inhibited by Fal-002-2. Fal-002-2 also blocked the activation of Rac1 and Cdc42 in a concentration range that effectively inhibited PAK activation. Taken together, these results suggest that Fal-002-2 inhibits fMLP-stimulated O2(•-) generation in neutrophils mainly through the blockade of PKC and PAK signaling pathways and partly through p38 MAPK signaling.

p38 Mitogen-activated protein kinase and extracellular signal-regulated kinase signaling pathways are not essential regulators of formyl peptide-stimulated p47(phox) activation in neutrophils

Three structurally unrelated p38 mitogen-activated protein kinase (MAPK) inhibitors, (4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)imidazole (SB203580), 1-5-tert-butyl-2-p-tolyl-2H-pyrazol-3-yl)-3-[4-(2-morpholin-4-yl-ethoxy)naphthalen-1-yl] urea (BIRB 796) and 5-(2,6-dichlorophenyl)-2-[2,4-difluorophenyl]thio]-6H-pyrimido[1,6-b]pyridazin-6-one (VX 745) showed approximately 40% inhibition of formyl-Met-Leu-Phe (fMLP)-stimulated neutrophil superoxide anion (O2(•-)) generation at concentrations that greatly diminished p38 MAPK activity. However, a significant inhibition of p47(phox) activation occurred at concentrations much higher than the corresponding IC50 values of these inhibitors in blocking p38 MAPK activity. 4-Ethyl-2(p-methoxyphenyl)-5-(4'-pyridyl)-IH-imidazole (SB202474), an inactive analogue of SB203580, at a concentration (30μM) which significantly attenuated p38 MAPK activity, had no effect on p47(phox) activation, whereas it inhibited O2(•-) generation with an IC50 value of approximately 16μM. Moreover, both SB203580 and BIRB 796 had no effect on protein kinase B (PKB)/Akt Ser473 phosphorylation and S100A9 protein membrane translocation at concentrations that effectively blocked p38 MAPK activity. Pretreatment of cells with two structurally unrelated MAPK/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitors, 2-(2-amino-3-methoxy-phenyl)-chromen-4-one (PD 98059) and 1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio)butadiene (U0126), at concentrations that effectively blocked MEK activity, attenuated p47(phox) phosphorylation but did not affect the recruitment of p47(phox) to p22(phox) or O2(•-) generation. Both p47(phox) activation and O2(•-) generation were attenuated by a protein kinase C (PKC) inhibitor 2-[1-(3-dimethylaminopropyl)-1H-indol-3-yl]-3-(1H-indol-3-yl)-maleimide (GF 109203X) in the concentration range that effectively blocked PKC activity. Taken together, these results suggest that the ERK-mediated Ser phosphorylation of p47(phox) is not implicated in the assembly of NADPH oxidase or O2(•-) generation, and that O2(•-) generation is partly attributable to p38 MAPK signaling through mechanisms other than p47(phox) activation, Akt activation and S100A9 membrane recruitment in fMLP-stimulated neutrophils.

Early induction of cytokines/cytokine receptors and Cox2, and activation of NF-κB in 4-nitroquinoline 1-oxide-induced murine oral cancer model

The purpose of this study was to identify the genes induced early in murine oral carcinogenesis. Murine tongue tumors induced by the carcinogen, 4-nitroquinoline 1-oxide (4-NQO), and paired non-tumor tissues were subjected to microarray analysis. Hierarchical clustering of upregulated genes in the tumor tissues revealed an association of induced genes with inflammation. Cytokines/cytokine receptors induced early were subsequently identified, clearly indicating their involvement in oral carcinogenesis. Hierarchical clustering also showed that cytokine-mediated inflammation was possibly linked with Mapk6. Cox2 exhibited the greatest extent (9-18 fold) of induction in the microarray data, and its early induction was observed in a 2h painting experiment by RT-PCR. MetaCore analysis showed that overexpressed Cox2 may interact with p53 and transcriptionally inhibit expression of several downstream genes. A painting experiment in transgenic mice also demonstrated that NF-κB activates early independently of Cox2 induction. MetaCore analysis revealed the most striking metabolic alterations in tumor tissues, especially in lipid metabolism resulting from the reduction of Pparα and Rxrg. Reduced expression of Mapk12 was noted, and MetaCore analysis established its relationship with decreased efficiency of Pparα phosphorylation. In conclusion, in addition to cytokines/cytokine receptors, the early induction of Cox2 and NF-κB activation is involved in murine oral carcinogenesis.

The history of Ephedra (ma-huang)

Ephedra is a Chinese shrub which has been used in China for medicinal purposes for several thousand years. The pure alkaloid ephedrine was first isolated and characterised by Nagai in 1885. It was then forgotten until it was rediscovered by Chen and Schmidt in the early 1920s. Its actions on the adrenoceptors could be classified into separate alpha and beta effects--a defining moment in the history of autonomic pharmacology. Ephedrine became a highly popular and effective treatment for asthma, particularly because, unlike adrenaline (until then the standard therapy), it can be given by mouth. Ephedrine as a treatment for asthma reached its zenith in the late 1950s, since when there has been a gradual and inevitable decline in its therapeutic use. From mainstream medicine, ephedrine moved into the twilight zone of street drugs and nutritional supplements. Ephedra and ephedrine products are now banned in many countries, as they are a major source for the production of the addictive compound methamphetamine (crystal meth).

Co-treating with arecoline and 4-nitroquinoline 1-oxide to establish a mouse model mimicking oral tumorigenesis

The aim of this study was to establish an effective mouse model of oral cancer and to use this model to identify potential markers of oral tumor progression. C57BL/6JNarl mice were treated with arecoline, 4-nitroquinoline 1-oxide (4-NQO), or both arecoline and 4-NQO in high and low doses for 8 weeks to induce oral tumor. The induced oral lesions were observed for 20 weeks to assess the efficiency of cancer induction and survival rate of the mice. In addition, two target proteins that are frequently overexpressed during tongue cancer tumorigenesis, alphaB-crystallin and Hsp27, were examined by immunohistochemical analysis. In mice exposed to 4-NQO (200 microg/mL) and arecoline (500 microg/mL), the tongue lesions showed evidence of hyperplasia, papilloma, dysplasia, and carcinoma, and the lesions were pathologically similar to those lesions in human oral cancer. The tongue tumor incidence rate was 100% in mice exposed to concomitant 4-NQO (200 microg/mL) and arecoline (500 microg/mL) treatment, 57% in mice exposed to 4-NQO only, and 0% in mice exposed to arecoline only. Immunohistochemical analysis demonstrated that, consistent with human studies, alphaB-crystallin and Hsp27 were upregulated in murine oral tumors. In conclusion, we have established a powerful animal model that enables the study of the promoting effects of arecoline on tongue tumorigenesis. Data subsequently attained from this mouse model support a role for alphaB-crystallin and Hsp27 as clinical markers for tumor progression.

Mycophenolate mofetil in pyoderma gangrenosum

Recently, the use of mycophenolate mofetil (MMF) has expanded in dermatological practice. Three patients with PG received MMF in conjunction with prednisone and a fourth patient received MMF monotherapy daily. MMF in combination with prednisone in three of our patients and alone in our fourth patient induced healing of their ulcers. The first patient tolerated MMF apart from gastrointestinal upset, while treatment in our second patient was complicated by staphylococcal and pseudomonal sepsis. The third patient complained of palpitations and headaches.

The history of ergot of rye (Claviceps purpurea) I: from antiquity to 1900

This article outlines the history of ergot of rye up to 1900. Ergot is a fungal disease that affects many grasses but is particularly damaging to rye. It occurs as the result of an infection by the parasitic organism Claviceps purpurea, which produces characteristic black spurs on the grass. When incorporated into grain, the ergot fungus can cause severe outbreaks of poisoning in humans called ergotism. There are two main clinical forms of toxicity, gangrenous and convulsive, where coma and death often supervene: the death rate for ergotism has been reported to be between 10 and 20 per cent in major outbreaks. Historical accounts note that ergot could accelerate labour, stop postpartum haemorrhage and inhibit lactation. At the end of the nineteenth century ergot was still regarded as a 'glorious chemical mess', but help would arrive in the early 1900s and the complex jigsaw would be solved.

Effects of alendronate on a disintegrin and metalloproteinase with thrombospondin motifs expression in the developing epiphyseal cartilage in rats

A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been reported to play a role in the degradation of aggrecan, a major component of cartilage. This study was performed to examine the effects of alendronate on the expression of ADAMTS in developing femoral epiphyseal cartilage. Primary cultured chondrocytes from this cartilage were treated with alendronate in vitro and postnatal day 1 rats were injected subcutaneously with alendronate (1 mg/kg) every second day in vivo. The number of cultured chondrocytes and their aggrecan mRNA levels were unaffected by the alendronate treatment at 10(-6) to 10(-4) M concentrations. The mRNA levels of ADAMTS-1, -2 and -9 in chondrocytes were also unaffected. However, the levels of ADAMTS-5 and -4 were reduced significantly by the same treatment. The thickness of the proliferating chondrocyte layers and the aggrecan mRNA levels in the epiphysis were unaffected by the alendronate treatment in vivo. However, the hypertrophied chondrocyte layers became significantly thicker, and the size of the secondary ossification centre was reduced significantly by the same treatment (P < 0.05). Both ADAMTS-4 and -5 mRNA expressions were also reduced significantly in vivo. The immunoreactivity against ADAMTS-4 was seen in hypertrophied chondrocytes and reduced significantly by the alendronate treatment. These results suggested that alendronate can inhibit the degradation of aggrecan in the articular cartilage by downregulating the expression of matrix enzymes such as ADAMTS-4 and -5.

Ipecacuanha: the South American vomiting root

The story of ipecacuanha, derived from the plant Cephaelis, is a fascinating one. It was discovered in Brazil in the 1600s and then transported to Paris in the latter part of the same century. It was used there by the physician Helvetius on various members of the French royal court to treat the flux (dysentery) with some success. Later, in the eighteenth century, it was taken up by the physician and privateer Thomas Dover and became, with opium, a fundamental constituent of his celebrated powder, which was used widely to treat fevers and agues for the next 200 years. Progress was then delayed until the early 1800s when the School of Chemistry at Paris established that the dried root of ipecac contained two powerful alkaloids, emetine and cephaeline, that consistently caused vomiting and diarrhoea. The discovery of the pathogenic amoeba, Entamoeba histolytica, in the latter part of the nineteenth century, allowed a distinction to be made between the two main forms of dysentery (amoebic and bacillary). Emetine was shown to be active against the amoebic form of dysentery but ineffective against that caused by bacteria. Ipecacuanha, its root and the pure alkaloid emetine have now been abandoned on the grounds of toxicity. They have been replaced by safer, more effective compounds. Nevertheless, they deserve an honoured place in the history of medicine, especially in the search for an effective treatment for amoebic dysentery.

Inhibition of lipopolysaccharide-stimulated NO production by a novel synthetic compound CYL-4d in RAW 264.7 macrophages involving the blockade of MEK4/JNK/AP-1 pathway

In the present study, a novel synthetic compound 4-(2-(cyclohex-2-enylidene)hydrazinyl)quinolin-2(1H)-one (CYL-4d) was found to inhibit lipopolysaccharide (LPS)-induced nitric oxide (NO) production without affecting cell viability or enzyme activity of expressed inducible NO synthase (iNOS) in RAW 264.7 macrophages. CYL-4d exhibited parallel inhibition of LPS-induced expression of iNOS protein, iNOS mRNA and iNOS promoter activity in the same concentration range. LPS-induced activator protein-1 (AP-1) DNA binding, AP-1-dependent reporter gene activity and c-Jun nuclear translocation were all markedly inhibited by CYL-4d with similar efficacy, whereas CYL-4d produced a weak inhibition of nuclear factor-kappaB (NF-kappaB) DNA binding, NF-kappaB-dependent reporter gene activity and p65 nuclear translocation without affecting inhibitory factor-kappa B alpha (I kappa B alpha) degradation. CYL-4d had no effect on the LPS-induced phosphorylation of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and its upstream activator MAPK kinase (MEK) 3, whereas it significantly attenuated the phosphorylation of c-Jun, c-Jun NH(2)-terminal kinase (JNK) and its upstream activator MEK4 in a parallel concentration-dependent manner. Other Toll-like receptors (TLRs) ligands (peptidoglycans, double-stranded RNA, and oligonucleotide containing unmethylated CpG motifs)-induced iNOS protein expression were also inhibited by CYL-4d. Furthermore, the NO production from BV-2 microglial cells as well as rat alveolar macrophages in response to LPS was diminished by CYL-4d. These results indicate that the blockade of NO production by CYL-4d in LPS-stimulated RAW 264.7 cells is attributed mainly to interference in the MEK4-JNK-AP-1 signaling pathway. CYL-4d inhibition of NO production is not restricted to TLR4 activation and immortalized macrophage-like cells.

Solanaceae IV: Atropa belladonna, deadly nightshade

The Deadly Nightshade, Atropa belladonna, is a plant surrounded by myth, fear and awe. In antiquity, the Greeks and the Romans knew that it contained a deadly poison. In medieval times, it was widely used by witches, sorcerors and professional poisoners. Linnaeus later codified its remarkable properties as the genus Atropa, the Fate that slits the thin spun life and the species belladonna because of its power to dilate the pupils. In the 1830s, the pure alkaloid I-atropine was isolated from the plant. This proved to be a significant tool in the study of the autonomic nervous system leading to the identification of acetylcholine as an important neurotransmitter in mammals. When pure atropine became available, it caused a large number of deaths, whether by accident, suicide or homicide.

Efficacy of moxibustion after rolling correction in dairy cows with abomasal displacement

This study was performed to assess the efficacy of moxibustion after rolling correction in dairy cows with abomasal displacement (AD). The experimental group comprised 86 Holstein cows with left displacement of the abomasum (LDA) and right displacement of the abomasum (RDA), with a mean age of 3.8 with AD during a 2-year period. The cows were rolled for correction of AD. After the rolling procedure, moxibustion was conducted on six acupoints once a day during the course of treatment. After repositioning the abomasums, the bilateral points of BL-20, BL-21 and BL-26 were then stimulated. During the follow-up of 1 week, 67 (93.1%) of 72 LDA and 12 (85.7%) of 14 RDA cows were released as cured after moxibustion. In conclusion, moxibustion effectively treats AD following rolling correction in dairy cows.

Solanaceae III: henbane, hags and Hawley Harvey Crippen

Hyoscyamus, the henbane, is one of the drugs of the ancients. Initially used both as a poison and narcotic, it was widely adopted by witches, wizards and soothsayers as a component of their hallucinatory and flying ointments. It was also used by notorious poisoners such as Madame Voisin in France. Eventually, in the nineteenth century its active principle was isolated by Ladenburg and called l-hyoscine. It proved to be a tropane alkaloid very similar to atropine. These two alkaloids proved to be very important in the study of the parasympathetic component of the autonomic nervous system, and together with physostigmine, allowed the major neurotransmitter acetylcholine to be isolated and its mechanisms of action to be characterised. The Crippen murder case in 1910 gave hyoscine further fame, indeed, notoriety. The unassuming homeopathic doctor murdered his wife with the alkaloid and then decamped for Canada with his mistress Ethel Le Neve. The case became a worldwide sensation for several reasons: the arrest of the fugitive couple by wireless telegraphy (Marconigram) and the extensive chemical and histological evidence presented by Willcox and Spilsbury. Some authorities claim that this was the beginning of the science of forensic medicine in Britain. Hyoscine is now hardly ever used in modern therapeutics but its history from antiquity to the witches and on to Dr Crippen is both bizarre and fascinating.

The Solanaceae: foods and poisons

The plant family Solanaceae contains important foodstuffs such as the potato, tomato and aubergine, together with powerful poisons including mandrake, henbane and deadly nightshade. In the first article in this short series on the family, the history and importance of the potato are described. It was first cultivated by the Inca people in the altiplano of the Andes in prehistoric times. Then it was translocated to Europe by the Spanish invaders. Originally reviled as'peasant food', it was regarded with great suspicion as an evil plant and a potential cause of leprosy. Over several centuries it gradually became established throughout Britain, France and the continent, and in particular in Ireland, where its growth allowed the population to expand very rapidly between 1750 and 1850. In the late 1840s, nemesis arrived in the form of the potato blight and the Irish famine. The 'tatties' went black, a great hunger ensued and thousands died. Later, the causative fungus was isolated and steps were taken to avoid further similar disasters. It is not generally appreciated that potatoes can be poisonous if they are turning green or sprouting (chitting). The tuber is then producing toxic quantities of the alkaloid alpha-solanine. The clinical syndrome of potato poisoning is described briefly.

Inhibition of lipopolysaccharide-stimulated NO production by crotafuran B in RAW 264.7 macrophages involves the blockade of NF-κB activation through the increase in IκBα synthesis

Crotafuran B, a natural pterocarpanoid isolated from Crotalaria pallida, inhibited the lipopolysaccharide (LPS)-stimulated nitric oxide (NO) production (IC50 16.4+/-0.7 microM) and inducible nitric oxide synthase (iNOS) protein and mRNA expression (IC50 11.5+/-0.6 microM and 11.8+/-2.2 microM, respectively), but not via its cytotoxicity or the inhibition of iNOS enzyme activity, in RAW 264.7 macrophages. Crotafuran B also reduced the iNOS promoter activity (IC50 13.4+/-0.1 microM) in piNOS-LUC-transfected cells. Crotafuran B treatment inhibited the p65 nuclear translocation and the nuclear factor-kappaB (NF-kappaB) DNA binding activity in LPS-activated macrophages. Crotafuran B also reduced the NF-kappaB transcriptional activity in pNF-kappaB-LUC-transfected cells. Crotafuran B had no effect on the LPS-induced phosphorylation of inhibitory kappaBalpha (IkappaBalpha), but enhanced the cellular level of IkappaBalpha that rebounded to the basal levels and increased the IkappaBalpha mRNA expression. These results indicate that the crotafuran B inhibition of NO production involves a decrease in the iNOS gene expression via the inhibition of NF-kappaB activation through the increase in IkappaBalpha synthesis.

Pycnogenol induces differentiation and apoptosis in human promyeloid leukemia HL-60 cells

Pycnogenol, rich of many phytochemicals of medical value, is a commercialized nutrient supplement extracted from the bark of European coastal pine. In this study, we investigated the anti-tumor effects of Pycnogenol on HL-60, U937 and K562 human leukemia cell lines. We found that Pycnogenol inhibited cell proliferation dose- and time-dependently, and the IC(50)s of Pycnogenol on HL-60, U937 and K562 cells were 150, 40 and 100 microg/ml, respectively. When HL-60 cells were incubated with low concentrations of Pycnogenol (50, 100 and 125 microg/ml) for 24 h, a prominent G0/G1 arrest was observed, followed by gradual accumulation of sub-G0/G1 nuclei. At 48 h of treatment, 50-70% of HL-60 cells differentiated, as evidenced by morphological changes, NBT reduction, induction of NSE activity, and increases of cell surface expression of CD11b. However, results from Annexin V/PI staining, DAPI staining and DNA fragmentation assay indicated that Pycnogenol induced HL-60, U937 and K562 cell apoptosis at their respective IC(50)s after 24 h of treatments. Pretreatment of z-DEVD-fmk, a caspase-3 specific inhibitor, not only decreased caspase-3 activity but also reduced the percentage of apoptotic cells induced by Pycnogenol. This indicated that caspase-3 activation was involved in Pycnogenol induced-apoptosis. In conclusion, Pycnogenol induced differentiation and apoptosis in leukemia cells. Our data suggest that Pycnogenol could serve as a potent cancer chemopreventive or chemotherapeutic agent for human leukemia.

Changes in outcome with sphincter preserving surgery for rectal cancer in Korea, 1991-2000

AIM

To report the clinical and oncological data of patients operated on for rectal cancers 3-5 cm from the AV over a 10 year period, including the Sphincter preservation (SP) rate.

METHODS

We reviewed medical records of 304 patients with rectal cancers 3-5 cm from the AV who underwent surgical resection from January 1991 through December 2000. The 10 years were divided into three periods based on the introduction of new surgical techniques, specifically, ultralow anterior resection (ULAR) with double stapling in March 1994 and ULAR with coloanal anastomosis in April 1997. The rates of SP, complications and patient survival during these periods were compared.

RESULTS

The SP rate increased significantly over the 10 years, from 16.4% in period I (January 1991-February 1994), to 53.0% in period II (March 1994-March 1997), to 86.5% in period III (April 1997-December 2000) (p<0.001). Over time, the age of the patients increased (p=0.004), the length of the distal resection margin became shorter (p=0.005), and the rate of lymph node metastasis increased (p=0.016). The factors significantly influencing SP were the period (p<0.001) and the distance from the AV (p<0.001). Over time, morbidity did not increase, and overall and disease free survival rates did not decrease. In contrast, the overall survival of N2 cases significantly increased over time (p=0.0492).

CONCLUSION

Over 10 years, the SP rate in rectal cancers 3-5 cm from the AV was significantly increased by the introduction of the double stapling and coloanal anastomosis techniques. These surgical methods, however, had no effect on morbidity, disease free survival and overall survival rates.

Synthesis and anticancer activity of benzyloxybenzaldehyde derivatives against HL-60 cells

A series of benzyloxybenzaldehyde derivatives were prepared and tested against the HL-60 cell line for anticancer activity. Preliminary structure-activity relationships were established. It was discovered that 2-(benzyloxy)benzaldehyde (17), 2-(benzyloxy)-4-methoxybenzaldehyde (26), 2-(benzyloxy)-5-methoxybenzaldehyde (27), 2-(benzyloxy)-5-chlorobenzaldehyde (28), 2-[(3-methoxybenzyl)oxy]benzaldehyde (29), 2-[(2-chlorobenzyl)oxy]benzaldehyde (30), and 2-[(4-chlorobenzyl)oxy]benzaldehyde (31) exhibited significant activity at 1-10 microM. Among them, compound 29 was the most potent one. The morphological assessment and DNA fragmentation analysis indicated that these compounds arrested cell cycle progression at G2/M phase and induced cell apoptosis. They resulted in the loss of mitochondrial membrane potential after 12h of treatment.

Curare: the South American arrow poison

The history of curare is both curious and convoluted. A product of South American culture it emerged in the sixteenth century from the mists of antiquity at the same time as quinine, coca, and chocolate. Like quinine, at first came the extract but no plant, and later the plant but no chemical compound. It took more than 300 years and the efforts of many explorers and scientists to resolve the problem. These included Condamine, Humboldt, Brodie, Waterton, Bernard, Dale, Walker, and King. Finally, the pure compound d-tubocurarine was isolated from the liana Chondrodendron and synthesised. Its specific physiological action was blockade of the effect of acetylcholine at the neuro-muscular junction. Such a paralytic poison could be used to kill oneself or others. The bizarre plot to kill the Prime Minister, Lloyd George, during the First World War is described. Fortunately this nefarious plan was thwarted by the Secret Service!

Mutational analysis of OGG1, MYH, MTH1 in FAP, HNPCC and sporadic colorectal cancer patients: R154H OGG1 polymorphism is associated with sporadic colorectal cancer patients

MYH, OGG1 and MTH1 are members of base excision repair (BER) families, and MYH germline mutations were recently identified in patients with multiple adenomas or familial adenomatous polyposis (FAP). A total of 20 APC-negative Korean FAP patients were analyzed for OGG1, MYH and MTH1 germline mutations. A total of 19 hereditary nonpolyposis colorectal cancer (HNPCC), 86 suspected HNPCC, and 246 sporadic colorectal cancer cases were investigated for OGG1 and MYH mutations. A total of 14 R154H OGG1 polymorphisms were identified in hereditary, sporadic colorectal cancers, and normal controls. For the case-control analysis of OGG1 R154H, a total of 625 hereditary or sporadic colorectal cancer patients and 527 normal controls were screened. R154H was a rare polymorphism associated with sporadic colorectal cancer patents (OR: 3.586, P= 0.053). R154H does not segregate with cancer phenotypes. Upon examining the possibility of recessive inheritance of R154H, we could not identify any complementary mutations in OGG1, MYH or MTH1. Samples with R154H were further screened for mutations of K-ras, beta-catenin, APC, p53, BRAF and the microsatellite instability (MSI) status. Eight somatic mutations were identified in these genes and G:C to T:A transversion mutations were not dominant in samples harboring R154H. This result raises the possibility that OGG1 R154H may function as a low/moderate-penetrance modifier for colorectal cancer development.