Variation in plasma leptin levels in response to fasting in Antarctic fur seals (Arctocephalus gazella)

Plasma leptin levels were determined in 8 lactating female and 20 pup Antarctic fur seals (Arctocephalus gazella) during fasting periods of normal duration. Plasma leptin levels ranged from 1.35-3.19 ng·ml^-1 in lactating females and 1.79-4.80 ng·ml^-1 in pups and were not positively correlated with body mass or condition. A negative trend, however, was observed between plasma leptin levels and body condition in lactating females upon their arrival at the colony following a foraging trip (beginning of fast). In accordance with findings in other species, plasma leptin levels dropped significantly (P<0.02) in response to the 17-19% drop in body mass experienced by pups during fasting. In contrast, plasma leptin levels in lactating females increased during the first 24 h of fasting before decreasing throughout the remaining 48 h of the fast. This unexpected result could be due to the high level of energy expenditure by seals as they swim back to the colony (i.e. post-exercise response) or may be influenced by the intense suckling activity experienced by females during the onshore fasting periods. The results of this study support recent findings in other carnivore species which suggest the primary physiological role of leptin in these species may not necessarily be as a signal of the magnitude of body energy reserves.

The effects of a simplified tai-chi exercise program (STEP) on the physical health of older adults living in long-term care facilities : a single group design with multiple time points

Background
Studies support the positive effects that Tai Chi has on the physical health of older adults. However, many older adults residing in long-term care facilities feel too weak to practice traditional Tai Chi, and a more simplified style is preferred.
Objective
To test the effects of a newly-developed, Simplified Tai-Chi Exercise Program (STEP) on the physical health of older adults who resided in long-term care facilities.
Design
A single group design with multiple time points: three pre-tests, one month apart; four post-tests at one month, two months, three months, and six months after intervention started.
Settings
Two 300–400 bed veteran homes in Taiwan.
Participants
The 51 male older adults were recruited through convenience sampling, and 41 of them completed six-month study. Inclusion criteria included: (1) aged 65 and over; (2) no previous training in Tai Chi; (3) cognitively alert and had a score of at least eight on the Short Portable Mental Status Questionnaire; (4) able to walk without assistance; and (5) had a Barthel Index score of 61 or higher. Participants who had dementia, were wheel-chair bound, or had severe or acute cardiovascular, musculoskeletal, or pulmonary illnesses were excluded.
Methods
The STEP was implemented three times a week, 50 min per session for six months. The outcome measures included cardio-respiratory function, blood pressure, balance, hand-grip strength, lower body flexibility, and physical health actualization.
Results
A drop in systolic blood pressure (p=.017) and diastolic blood pressure (p<.001) was detected six months after intervention started. Increase in hand-grip strength from pre to post intervention was found (left hand: p<.001; right hand: p=.035). Participants also had better lower body flexibility after practicing STEP (p=.038).
Conclusions
Findings suggest that the STEP be incorporated as a floor activity in long-term care facilities to promote physical health of older adults.

Patterns of coronary heart disease mortality over the 20th century in England and Wales : possible plateaus in the rate of decline

Background
Coronary heart disease (CHD) rates in England and Wales between 1950 and 2005 were high and reasonably steady until the mid 1970s, when they began to fall. Recent work suggests that the rate of change in some groups has begun to decrease and may be starting to plateau or even reverse.

Methods
Data for all deaths between 1931 and 2005 in England and Wales were grouped by year, sex, age at death and contemporaneous ICD code for CHD as cause of death. CHD mortality rates by calendar year and birth cohort were produced for both sexes and rates of change were examined.

Results
The pattern of increased burden of CHD mortality within older age groups has only recently emerged in men, whereas it has been established in women for far longer. CHD mortality rates among younger people showed little variation by birth cohort. For younger women (49 and under), the rate of change in CHD mortality has reversed in the last 20 years, indicating a future plateau and possible reversal of previous improvement in CHD mortality rates. Among younger men the rate of change in CHD mortality has been consistent for the past 15 years indicating that rates in this group have continued to fall steadily.

Conclusion
Although CHD mortality rates continue to drop in older age groups the actual burden of coronary heart disease is increasing due to the ageing of the population. The rate of improvement in CHD mortality appears to be beginning to decline and may even be reversing among younger women.

Declining foreign enrollment at higher education institutions in the United States : a research note

When the Institute of International Education reported a drop of 2.4% in international student enrollment in the United States in 2003/2004, the first absolute decline in foreign enrollments since 1971/1972 (Open Doors, 2004), many were quick to point fingers at visa policies instituted after the September 11, 2001 attacks. The "Visas Mantis" review—a security clearance required for foreign students studying any of roughly 200 scientific fields—was blamed for tarnishing the view of the United States as a welcoming place for international students. Although the review has certainly been the cause of increased visa delays and rejections, this article takes the view that it is not the only cause for the dip in foreign enrollments in the United States. Through econometric analyses, it is shown that other than the visa quagmires, improved access to domestic education opportunities and tuition fee increases can indeed explain the drop in foreign enrollments.

Steroidogenesis in cultured mammalian glial cells

A protocol for culturing mammalian type 1 astrocytic cells, using female post-natal rat cerebral cortical tissue, was established and refined for use in steroidogenic metabolic studies incorporating progestin radioisotopes. Cultures were characterised for homogeneity using standard morphological and immunostaining techniques. Qualitative and quantitative studies were conducted to characterise the progesterone (P) metabolic pathways present in astrocytes in vitro. Of particular interest was the formation of the P metabolite, 5á-pregnan-3á-ol-20-one (THP). THP is a GABA(A) receptor agonist, believed to play a vital role in neural functioning and CNS homeostasis. One aim of this study was to observe any modulatory effects selected neuroactive ligands have on the conversion of P into THP, in an attempt to link astrocytic steroidogenesis with neuronal control. In qualitative studies, chromatographic procedures were used to establish the progestin profile of cerebral cortical astrocytes. Tritiated P, DHP (5á-pregnan-3,20-dione) and THP incurbates were preliminary fractionated by either normal phase (NP) or reverse phase (RP) high performance liquid chromatography (HPLC). The radiometabolites associated with each fraction were further chromatographed, before and/or after chemical derivatistation, by the aforemention HPLC procedures and thin layer chromatography (TLC). Steroid radiometabolites were tentatively identified by comparing their chromatographic mobility with authentic steroids. The identity of the main putative 5á-reduced P metabolities, DHP, THP and 5á-pregnan-3á,20á-diol (20áOH-THP) were further confirmed by isotopic dilution analysis. Their conclusive identification, along with the tentative identification of 20á-hydroxypreg-4-en-3-one (20áOH-P) and 20á-hydroxy-5á-pregnan-3-one (20áOH-DHP), verify the localisation of 5á-reductase, 3á-hydroxy steroif oxidoreductase (HSOR), and 20á-HSOR activity in the cultured astrocytes utilised in this study programme. Other minor metabolites detected were tentatively identified, including 5á-pregnan-3á,21-diol-20-one (THDoc), indicating the presence of 21-hydroxylase enzymatic activity. THDoc, like THP, is a GABA(A) receptor agonist. The chemical and physical characterisation of several yet unidentified progestin metabolites, associated with a highly polar RP HPLC fraction (designated RP peak 1*), indicate the presence of one or more extra hydroxylase enzymes. Quantitative analysis included a preliminary study. In this study, the percentage yields of radiometabolites formed in cultures incubated with increasing substrate concentrations of (3)H-P for 24 hours were determined. At the lower concentrations examined (ie 0.5 to 50nM), the metabolites associated with the polar RP HPLC fraction (RP peak 1*) collectively have the highest percentage yield. They are subsequently considered metabolic end products of degradative catabolic P pathways. The percentage yield of THP peaks in the medium concentration ranges (ie 5 to 500nM), whereas DHP remains fairly static at a low level with increasing concentration. Both DHP and THP are considered metabolic pathway intermediates. The percentage yield of 20áOH-THP continues to increase with increasing concentration over 5nM, superseding THP approaching the highest concentration examined (5000nM). This indicated the formation of 20áOH-THP does not occur entirely via THP. 20áOH-THP also possibly serves as the direct intermediate in the formation of the main radiometabolites associated with RP peak 1*. A time/yield study incorporating incubation times from one to 24 hours was also conducted. The full array of radiometabolites (individually or in groups) formed in astrocyte cultures incubated with 50nM tritiated P, DHP of THP, were assayed. Cultures were observed to rapidly convert any DHP into THP, showing astrocytic 3á-HSOR activity is very high. The study also showed 5á-reduction (ie the conversation of P into DHP) is the rate limiting reaction in the two step conversion of P into THP. 5á-Reduction also appears to be a rate limiting step in the formation of 20á-hydroxylated metabolites in astrocytes. Cultures incubated with the tritiated 5á-reduced pregnanes from one to four hours form greater quantities to 20á-hydroxylated radiometabolites compared to cultures incubated with (3)H-P. The time yield/studies also provided further evidence the unidentified polar radiometabolites associated with RP peak 1* are metabolic end products. For the P and DHP incubates, the collective formation of the aforementioned polar radiometabolites initially lags behind the formation of THP. As the formation of the latter begins to plateau with increasing time between four to 24 hours, the net yield of radiometabolites associated with RP peak 1* continues to rise. The time/yield studies also indicate 5á-reduction and perhaps 3á-hydroxylation are pre-requisite steps in the formation of the polar metabolites. Cultures incubated with the 5á-reduced progestins from one to four hours form higher yields of the radiometabolites associated with RP peak 1* compared to cultures incubated with P as substrate. The net yields of the radiometabolites associated with RP peak 1* for cultures incubated with THP were substantially higher compared to cultures incubated with DHP after equivalent times. The effect selected neuroligands have on the yield of radiometabolites formed by cultured astrocytes incubated with 50nM (3)H-P was also examined. Dibutyryl cyclic adenosine monophosphate (DBcAMP), not actually a neuroligand per se, but an analog of the intracellular secondary messenger cAMP, was also utilised in these studies. The inhibitory neurotransmitter ă-amino-nbutyric acid (GABA), DBcAMP and isoproterenol (a â-adrenergic receptor agonist) all quickly induce a transient but substantial increase in 20á-HSOR activity in cultured astrocytes. Cultures pretreated with these three compounds (10, 20 and 1µM respectively) form substantially higher yields of 20á-hydroxylated metabolites, including 20áOH-THP (between 200 to 580% greater), when incubated with 50nM (3)H-P for one to four hours. These increases also coincide with increases in the net yield of metabolites formed (by 16 to 48%). The same pre-treated cultures form significantly lower yields of THP, by 25 to 41%, after one hour. This is most likely due to the increased metabolism of any formed THP into 20áOH-THP. Octopamine (an á-adrenergic agonist) only induces a slight increase in 20á-HSOR activity, having relatively little effect on the yield of 20áOH-THP formed. Pretreatment with octopamine induces a significant increase in the yield of THP for cultures incubated with (3)H-P for four hours (by 24%). The increase in THP formation appears to be due to an increase in 3á-HSOR activity, as judged by the concomitant drop in the yield of the 5á-reduced, 3-keto substrates. An increase in 5á-reductase activity cannot be excluded however. Isoproterenol appears to induce an increase in 5á-reductase activity as isoproterenol appears to induce an increase in 5á-reductase activity as isoproterenol one and four hour incubates have higher yields of DHP. This is in contrast to the other three incubates. After 12 hours, all incubates have higher yields of THP (15-30%).

Improving student learning in dissertation research through feedback studies. The Sheffield Hallam Building surveying experience

According to George and Cowan (1999) student feedback is essential to enable lecturers to understand whether attempts to improve learning and educational experience lead to improvement. Current UK practice uses end of module questionnaires to feedback levels of satisfaction (Cowan, 2002). There are inherent weaknesses, namely that it seldom leads to a change for that particular cohort of students, secondly it relies on uncorroborated opinion, and may derive from superficial feedback from a minority of students with the remainder suffering from questionnaire fatigue. Finally the data may not be especially relevant to a particular module, a particular weakness (Heywood, 2000).

Using principles identified by Angelo and Cross (1993), this research adopted a methodology to formatively evaluate student perceptions and levels of satisfaction with the dissertation module. Using a cohort of Building Surveying students at Sheffield Hallam University, in England, views on course materials, the use of Blackboard software, the workshops and the relationships with supervisors were gathered and analysed.

A number of measures were identified as a result of this study, that may, if implemented, improve student learning. Examples are the use of checklists for student for each research / dissertation stage to ensure nothing is forgotten. Provision of additional ‘drop in’ workshops where students could see the module leader with specific issues. Additional optional workshops for questionnaire coding and review of previous theses for example.

It will not be possible to measure whether this student cohort’s learning and performance improves until the summer of 2003 and the final dissertations are assessed. A statistical analysis, comparing their dissertation marks against marks for other topics will show whether there is improvement in marks as a result of this student feedback study. The 2002/3 cohort result can also be analysed against previous cohorts to establish whether any improvement is evident.

Surprising effect of nanoparticle inclusion on ion conductivity in a lithium doped organic ionic plastic crystal

Doping lithium bis(trifluoromethanesulfonyl)amide (Li[NTf₂]) into the N-ethyl,N′-methylpyrrolidinium bis(trifluoromethanesulfonyl)amide ([C₂mpyr][NTf₂]) plastic crystal material has previously indicated order of magnitude enhancements in ion transport and conductivity over pure [C₂mpyr][NTf₂]. Recently, conductivity enhancements in this ionic plastic crystal induced by SiO₂ nanoparticles have also been reported. In this work the inclusion of SiO₂ nanoparticles in Li ion doped [C₂mpyr][NTf₂] has been investigated over a wide temperature range by differential scanning calorimetry (DSC), impedance spectroscopy, positron annihilation lifetime spectroscopy (PALS), Raman spectroscopy, NMR spectroscopy and scanning electron microscopy (SEM). Solid state ¹H NMR indicates that the addition of the nanoparticles increases the mobility of the [C₂mpyr] cation and positron lifetime spectroscopy (PALS) measurements indicate an increase in mean defect size and defect concentration as a result of nanoparticle inclusion, especially with 10 wt% SiO₂. Thus, the substantial drop in ion conductivity observed for this doped nanocomposite material was surprising. This decrease is most likely due to the decrease in mobility of the [NTf₂] anion, possibly by its adsorption at the SiO₂/grain boundary interface and concomitant decrease in mobility of the Li ion.

The antimicrobial efficacy of elaeis guineensis : characterization, in Vitro and in Vivo studies

The urgent need to treat multi-drug resistant pathogenic microorganisms in chronically infected patients has given rise to the development of new antimicrobials from natural resources. We have tested Elaeis guineensis Jacq (Arecaceae) methanol extract against a variety of bacterial, fungal and yeast strains associated with infections. Our studies have demonstrated that E. guineensis exhibits excellent antimicrobial activity in vitro and in vivo against the bacterial and fungal strains tested. A marked inhibitory effect of the E. guineensis extracts was observed against C. albicans whereby E. guineensis extract at =, 1, or 2 times the MIC significantly inhibited C. albicans growth with a noticeable drop in optical density (OD) of the bacterial culture. This finding confirmed the anticandidal activity of the extract on C. albicans. Imaging using scanning (SEM) and transmission (TEM) electron microscopy was done to determine the major alterations in the microstructure of the extract-treated C. albicans. The main abnormalities noted via SEM and TEM studies were the alteration in morphology of the yeast cells. In vivo antimicrobial activity was studied in mice that had been inoculated with C. albicans and exhibited good anticandidal activity. The authors conclude that the extract may be used as a candidate for the development of anticandidal agent.

Prevention of aromatase inhibitor-induced bone loss with alendronate in postmenopausal women: the BATMAN trial

Abstract:
Postmenopausal women on aromatase inhibitors (AI) are at risk of aromatase inhibitor-associated bone loss (AIBL) and fractures.

In 2005 Osteoporosis Australia proposed an algorithm for bisphosphonate intervention. Three hundred and three postmenopausal women with early breast cancer (EBC) were enrolled (osteoporotic, n=25; osteopaenic, n=146; normal bone mineral density (BMD), n=126). Weekly alendronate (70 mg) treatment efficacy as triggered by the algorithm in preventing bone loss was evaluated. All patients received anastrozole (1 mg daily), calcium and vitamin D.

Results:
All osteoporotic patients received alendronate at baseline. Eleven out of the 146 (7.5%) osteopaenic patients commenced alendronate within 18 months of participation and eleven commenced after. One hundred and twenty four out of the 146 (84.9%) osteopaenic patients and all 126 with normal baseline BMD did not trigger the algorithm.

At three years, lumbar spine mean BMD increased (15.6%, p<0.01) in the osteoporotic group. BMD in the osteopaenic group with early intervention significantly increased at three years (6.3%, p=0.02). No significant change was seen in the late intervention group. No change was observed in those with osteopaenia without alendronate.

There was a significant drop in lumbar spine (−5.4%) and hip (−4.5%) mean BMD, in the normal BMD group, none of whom received alendronate.

Fracture data will be presented.

Conclusion:
In postmenopausal women with endocrine-responsive EBC, BMD improved over time when a bisphosphonate is administered with anastrozole in osteoporotic patients using an osteoporosis schedule. Subjects with normal baseline BMD experienced the greatest BMD loss, although none became osteoporotic.

Storm water harvesting and reuse in Australia : enhanced sand filtration for the treatment of storm water

This study details the removal of common storm water pollutants along with heavy metals by enhanced sand filtration. Three filtration flow rates were trialled: 5, 10 and 20 m/h. The performance of each filter was rated on the ability to remove turbidity, suspended solids, dissolved solids, phosphorus, nitrogen, lead, copper and Zinc. Conventional sand filter was used as a performance benchmark, and compared with four sand filters that are enhanced with a nylon carpet fibre, polypropylene carpet fibre, Syrian carpet fibre-enhanced and alum sludge-enhanced sand filter. Carpet fibre-enhanced sand filtration was highly effective at filtering simulated storm water and in most cases performing well above the conventional sand filters. The carpet fibre-enhanced sand filters had no drop in flow rates over the 4 h filtration period with following removal rates: up to 90% total suspended solids, 70% zinc, 60% turbidity, 25% phosphorus, 15% nitrogen and 10% total dissolved solids. However, results showed that alum sludge-enhanced sand filter performed the highest, with removal rates up to 100% for total suspended solids, 80% zinc, 90% turbidity, up to 80% phosphorus, up to 40% nitrogen and 3% total dissolved solids. But the flow rates dropped approximately two-thirds of the original flow rates within the first hour. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

Sucrose and lollypops to reduce immunisation pain in toddlers and young children: two pilot randomised controlled trials

Aims To evaluate the feasibility, acceptability and preliminary efficacy of sweet taste in reducing pain in toddlers and pre-school children during immunisation and to use the results to inform a sample size estimation for future full-scale trials. Background Sweet solutions reduce procedural pain in newborn infants and in infants beyond the newborn period. It is unclear if sweet taste continues to reduce procedural pain in children older than one year of age. Design Two parallel design pilot randomised controlled trials (RCTs). Methods Children attending an Immunisation Drop-in Clinic at a children's hospital in Australia participated in one of two pilot RCTs: 1) a double-blinded RCT of 33% sucrose compared to water in toddlers receiving their 12- or 18-month immunisation or 2) a non-blinded RCT of lollypop compared to standard care (active distraction using bubble and pin wheel blowing) in pre-school children aged 3-5 years. Primary outcomes included cry incidence and duration and pain score using the FLACC. Results Interventions, standard care and all aspects of the study were acceptable to children, parents and immunisation nurses. More toddlers in the sucrose group received their 12-month immunisation and more injections (n=35) compared to toddlers randomised to water (n=26). There were no significant differences in crying time or pain scores between intervention and control groups in either pilot RCT. Conclusion The study interventions are acceptable to children and parents. Full-scale trials would be feasible to conduct. Implications for clinical practice Toddlers receiving their 12-month immunisation should be the focus of future full-scale RCTs.

Changes in the platelet intracellular calcium response to serotonin in patients with major depression treated with electroconvulsive therapy: state or trait marker status.

Platelet serotonin type 2A receptor (5-HT2A) sensitivity changes have previously been documented in depression, although it is unclear if this represents a stable trait marker of the illness, or whether it represents an acute state marker of depression that would change with treatment. Electroconvulsive therapy (ECT) may be a useful intervention to separate out trait and state marker status avoiding the potential confounding effects of pharmacotherapy on receptor function. Using spectrofluorometry, the platelet 5HT2A, receptor sensitivity as reflected by the intracellular calcium response to serotonin stimulation, was measured every week in patients suffering from major depression and undergoing ECT. There was a significant drop in the platelet response to serotonin stimulation over a course of ECT, with an associated progressive decrease in Hamilton Rating Scale of Depression (HAM-D) scores. This may suggest either decreased sensitivity of platelet 5HT2A receptors as a mechanism of action of ECT, or changes in second messengers such as the inositide phospholipid system. This suggests that the enhanced sensitivity of platelet 5HT2A receptors may be a state marker of major depression.

Doxorubicin conjugated to immunomodulatory anticancer lactoferrin displays improved cytotoxicity overcoming prostate cancer chemo resistance and Inhibits tumour development in TRAMP mice

Advanced, metastatic, castration resistant and chemo-resistant prostate cancer has triggered change in the drug development landscape against prostate cancer. Bovine lactoferrin (bLf) is currently attracting attention in clinics for its anti-cancer properties and proven safety profile. bLf internalises into cancer cells via receptor mediated endocytosis, boosts immunity and complements chemotherapy. We employed bLf as an excellent functional carrier protein for delivering doxorubicin (Dox) into DU145 cells, CD44+/EpCAM+ double positive enriched DU145 3D prostaspheres and drug resistant ADR1000-DU145 cells, thus circumventing Dox efflux, to overcome chemo-resistance. Successful bLf-Dox conjugation with iron free or iron saturated bLf forms did not affect the integrity and functionality of bLf and Dox. bLf-Dox internalised into DU145 cells within 6 h, enhanced nuclear Dox retention up to 24 h, and proved significantly effective (p < 0.001) in reducing LC50 value of Dox from 5.3 μM to 1.3 μM (4 fold). Orally fed iron saturated bLf-Dox inhibited tumour development, prolonged survival, reduced Dox induced general toxicity, cardiotoxicity, neurotoxicity in TRAMP mice and upregulated serum levels of anti-cancer molecules TNF-α, IFN-γ, CCL4 and CCL17. The study identifies promising potential of a novel and safer bLf-Dox conjugate containing a conventional cytotoxic drug along with bLf protein to target drug resistance.

An integrated model of care for inflammatory bowel disease sufferers in Australia: development and the effects of its implementation.

BACKGROUND: Psychological comorbidities are associated with poor outcome and increased healthcare utilization in patients with inflammatory bowel disease (IBD). However, a model of care addressing the biopsychosocial dimension of disease is not routinely applied in IBD. This review describes the development of such a model and the effects of its implementation in a hospital-based cohort of patients with IBD. METHODS: Three different approaches were used: 1) collecting baseline epidemiological data on mental health comorbidities; 2) raising awareness of and targeting mental health problems; 3) examining the effects of the model implementation. RESULTS: High rates of anxiety and depressive symptoms (36% and 13%, respectively) that are maintained over time were identified in IBD patients presenting at a metropolitan teaching hospital. Patients with documented psychological comorbidities were more likely to be hospitalized than those without (odds ratio [OR] = 4.13, 95% confidence interval [CI]: 1.25, 13.61). Improvements in disease activity, anxiety, depression, quality of life, and coping have been noted when cognitive-behavioral therapy (CBT) was provided to patients. A drop in the use of opiates (P = 0.037) and hospitalization rates (from 48% to 30%) in IBD patients has been noted as a result of introduction of the changed model of care. In addition, the mean total cost of inpatient care was lower for IBD patients than controls (US$12,857.48 [US$15,236.79] vs. US$ 30,467.78 [US$ 53,760.20], P = 0.005). CONCLUSION: Our data to date suggest that an integrated model of care for patients with IBD may yield superior long-term outcomes in terms of medication use and hospitalization rates and reduce healthcare costs.

Lower permian oncolites from South China: implications for equatorial sea-level responses to late palaeozoic Gondwanan glaciation

The oncoid-bearing Chuanshan Formation is a regionally extensive carbonate deposit of predominantly Asselian to early Sakmarian (Early Permian) age in South China, occupying an area of some 500,000 km2. Throughout South China, the oncoid-bearing horizons are generally stable and broadly comparable in lithology, fossil content and the morphology of the oncoid grains. Four types of microfacies are recognized from the oncolite succession and overall they suggest a moderate- to high-energy, wave-agitated shallow marine carbonate platform environment. An analysis of the stratigraphic distribution of oncoid grain size, density, thickness and the bedding structures of the oncolite beds and the number of coating laminae indicate the presence of metre-scale cyclothems, suggestive of possible high-frequency cycles of sea-level fluctuation. Compared to carbonate successions above and below that lack oncolites, and in conjunction with evidence from sequence stratigraphic and isotopic geochemical analyses of coeval carbonate deposits in South China and elsewhere, the origin of the Chuanshan oncolites is linked to a drastic drop in global sea-level at the Pennsylvanian–Permian boundary, that can be correlated closely in timing with the zenith of the Late Palaeozoic Gondwanan glaciation. It is further suggested that the eustatic changes apparent from the deposition of the Chuanshan oncolites and similar coeval deposits in lower palaeolatitudes were coupled with, and influenced by, the contemporaneous high-latitude Gondwanan glaciation, the largest and longest known such event in Phanerozoic Earth history.