Participants in the Trans-Antarctic Winter Traverse Expedition Showed Increased Bacterial Load and Diversity in Saliva but Maintained Individual Differences within Stool Microbiota and Across Metabolite Fingerprints

Understanding the impact of long-term physiological and environmental stress on the human microbiota and metabolome may be important for the success of space flight. This work is logistically difficult and has a limited number of available participants. Terrestrial analogies present important opportunities to understand changes in the microbiota and metabolome and how this may impact participant health and fitness. Here, we present work from one such analogy: the Transarctic Winter Traverse expedition, which we believe is the first assessment of the microbiota and metabolome from different bodily locations during prolonged environmental and physiological stress. Bacterial load and diversity were significantly higher during the expedition when compared with baseline levels (p < 0.001) in saliva but not stool, and only a single operational taxonomic unit assigned to the Ruminococcaceae family shows significantly altered levels in stool (p < 0.001). Metabolite fingerprints show the maintenance of individual differences across saliva, stool, and plasma samples when analysed using flow infusion electrospray mass spectrometry and Fourier transform infrared spectroscopy. Significant activity-associated changes in terms of both bacterial diversity and load are seen in saliva but not in stool, and participant differences in metabolite fingerprints persist across all three sample types.

Optimising an intervention to support home-living older adults at risk of malnutrition: a qualitative study

Background

In the UK, about 14% of community-dwelling adults aged 65 and over are estimated to be at risk of malnutrition. Screening older adults in primary care and treating those at risk may help to reduce malnutrition risk, reduce the resulting need for healthcare use and improve quality of life. Interventions are needed to raise older adults’ risk awareness, offer relevant and meaningful strategies to address risk and support general practices to deliver treatment and support.

Methods

Using the Person-based Approach and input from Patient and Public Involvement representatives, we developed the ‘Eat well, feel well, stay well’ intervention. The intervention was optimised using qualitative data from think aloud and semi-structured process evaluation interviews with 23 and 18 older adults respectively. Positive and negative comments were extracted to inform rapid iterative modifications to support engagement with the intervention. Data were then analysed thematically and final adjustments made, to optimise the meaningfulness of the intervention for the target population.

Results

Participants’ comments were generally positive. This paper focuses predominantly on participants’ negative reactions, to illustrate the changes needed to ensure that intervention materials were optimally relevant and meaningful to older adults. Key factors that undermined engagement included: resistance to the recommended nutritional intake among those with reduced appetite or eating difficulties, particularly frequent eating and high energy options; reluctance to gain weight; and a perception that advice did not align with participants’ specific personal preferences and eating difficulties. We addressed these issues by adjusting the communication of eating goals to be more closely aligned with older adults’ beliefs about good nutrition, and acceptable and feasible eating patterns. We also adjusted the suggested tips and strategies to fit better with older adults’ everyday activities, values and beliefs.

Conclusions

Using iterative qualitative methods facilitated the identification of key behavioural and contextual elements that supported engagement, and issues that undermined older adults’ engagement with intervention content. This informed crucial revisions to the intervention content that enabled us to maximise the meaningfulness, relevance and feasibility of the key messages and suggested strategies to address malnutrition risk, and therefore optimise engagement with the intervention and the behavioural advice it provided.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-021-01572-z.

Refeeding risks in patients requiring intravenous nutrition support: Results of a two-centre, prospective, double-blind, randomised controlled trial

BACKGROUND/AIMS

Refeeding syndrome can result following excessive feeding of malnourished patients. The syndrome remains poorly defined but encompasses a range of adverse effects including electrolyte shifts, hyperglycaemia and other less well-defined phenomena. There are additional risks of underfeeding malnourished individuals. Studies of refeeding syndrome have generally focussed on critical care environments or patients with anorexia nervosa. Here we have conducted a two-centre, prospective, double-blind, randomised controlled trial amongst all patients referred to hospital nutrition support teams for intravenous nutrition support. We sought to determine whether electrolyte and other abnormalities suggestive of refeeding syndrome risk varied depending on initial rate of intravenous feeding.

METHODS

Patients at moderate or high risk of refeeding syndrome, as defined by United Kingdom National Institute of Health and Care Excellence guidelines, were screened for inclusion. Patients were randomised to receive either high (30 kcal/kg/day, 0.25 gN/kg/day) or low (15 kcal/day, 0.125 gN/kg/day) rate feeding for the first 48 h prior to escalation to standard parenteral nutrition regimens. The primary outcome was rates of potential refeeding risks within the first 7 days as defined by electrolyte imbalance or hyperglycaemia requiring insulin. Secondary outcomes included effects on QTc interval, infections and length of hospital stay. Statistical analysis was performed with χ² or Wilcoxon rank sum tests and all analysis was intention-to-treat. Problems with study recruitment led to premature termination of the trial. Registered on the EU Clinical Trials Register (EudraCT number 2007-005547-17).

RESULTS

534 patients were screened and 104 randomised to either high or low rate feeding based on risk of refeeding syndrome. Seven patients were withdrawn prior to collection of baseline demographics and were excluded from analysis. 48 patients were analysed for the primary outcome with potential refeeding risks identified in 46%. No differences in risks were seen between high and low rate feeding (p > 0.99) or high and moderate risk feeding (p = 0.68). There were no differences in QTc abnormalities, infection rates, or hospital length of stay between groups.

CONCLUSIONS

In this randomised trial of rates of refeeding risk, in patients pre-stratified as being at high or moderate risk, we found no evidence of increased refeeding related disturbances in those commenced on high rate feeding compared to low rate. No differences were seen in secondary endpoints including cardiac rhythm analysis, infections or length of stay. Our study reflects real world experience of patients referred for nutrition support and highlights challenges encountered when conducting clinical nutrition research.

Beliefs about inevitable decline among home-living older adults at risk of malnutrition: a qualitative study

BACKGROUND

Approximately 14% of free-living adults aged ≥65 years are at risk of malnutrition. Malnutrition screen and treat interventions in primary care are few, show mixed results, and the advice given is not always accepted and followed. We need to better understand the experiences and contexts of older adults when aiming to develop interventions that are engaging, optimally persuasive and relevant.

METHODS

Using the Person-based Approach, we carried out 23 semi-structured interviews with purposively selected adults ≥65 years with chronic health or social conditions associated with malnutrition risk. Thematic analysis informed the development of key principles to guide planned intervention development.

RESULTS

We found that individuals' beliefs about an inevitable decline in appetite and eating in older age compound the many and varied physical and physiological barriers that they experience. Also, we found that expectations of decline in appetite and physical ability may encourage resignation, reduce self-efficacy to overcome barriers, and reduce motivation to address weight loss and/or recognise it as an issue that needs to be addressed. Fear of loss of independence may also reduce the likelihood of asking general practitioners for advice.

CONCLUSIONS

The key findings identified include a sense of resignation, multiple different barriers to eating and a need for independence, each underpinned by the expectation of a decline in older adulthood. Interventions need to address misperceptions about the inevitability of decline, highlight how and why diet recommendations are somewhat different from recommendations for the general population, and suggest easy ways to increase food intake that address common barriers.

Blood Flow Restriction Training for the Rotator Cuff: A Randomized Controlled Trial

CONTEXT

Blood flow restriction (BFR) training utilizes a tourniquet, applied to the proximal portion of one or more extremities, to occlude blood flow during exercise. Significant gains in strength and cross-sectional area can be achieved in muscles, both distal and proximal to BFR cuff application.

PURPOSE

To compare strength gains of the rotator cuff and changes in tendon size in subjects who performed side-lying external-rotation exercise with or without BFR.

METHODS

Forty-six subjects (mean age 25.0 [2.2] y) were randomized to either a BFR + exercise group or to the exercise-only group. Subjects performed 4 sets of the exercise (30/15/15/15 repetitions) at 30% 1-repetition maximum 2 days per week for 8 weeks.

RESULTS

Subjects in both groups experienced strength gains in the supraspinatus and the external rotators (P = .000, P = .000). However, there was no difference in strength gains between groups for the supraspinatus (P = .750) or the external rotators (P = .708). Subjects in both groups experienced increases in supraspinatus tendon thickness (BFR P = .041, exercise only P = .011). However, there was no difference between groups (P = .610).

CONCLUSIONS

Exercise with BFR applied to the proximal upper extremity did not augment rotator cuff strength gains or tendon thickness when compared with subjects who only exercised. This study did demonstrate that performing multiple sets of high repetitions at a low load led to significant increases in rotator cuff strength and tendon size in the dominant upper extremity.

Human physiological and metabolic responses to an attempted winter crossing of Antarctica: the effects of prolonged hypobaric hypoxia

An insufficient supply of oxygen to the tissues (hypoxia), as is experienced upon high‐altitude exposure, elicits physiological acclimatization mechanisms alongside metabolic remodeling. Details of the integrative adaptive processes in response to chronic hypobaric hypoxic exposure remain to be sufficiently investigated. In this small applied field study, subjects (n = 5, male, age 28–54 years) undertook a 40 week Antarctica expedition in the winter months, which included 24 weeks residing above 2500 m. Measurements taken pre‐ and postexpedition revealed alterations to glucose and fatty acid resonances within the serum metabolic profile, a 7.8 (±3.6)% increase in respiratory exchange ratio measured during incremental exercise (area under curve, P > 0.01, mean ± SD) and a 2.1(±0.8) % decrease in fat tissue (P < 0.05) postexpedition. This was accompanied by an 11.6 (±1.9) % increase (P > 0.001) in VO₂ max corrected to % lean mass postexpedition. In addition, spine bone mineral density and lung function measures were identified as novel parameters of interest. This study provides, an in‐depth characterization of the responses to chronic hypobaric hypoxic exposure in one of the most hostile environments on Earth.

Does hands-free drinking improve patient hydration?

Hospital patients are at risk of dehydration, especially if they cannot drink unaided due to physical or mental incapacity. Dehydration may lead to complications and result in costly interventions. A sports-style bottle has been developed into a hands-free drinking system by fitting a drinking tube into the screw top. We trialled the bottle on acute wards and in the community to test claims that it improves hydration and reduces infection risks and length of hospital stays. The Hydrant is useful and even transformative for some patients. However, it is less suitable for older people, especially those in rehabilitation programmes.

Overfeeding and overhydration in elderly medical patients: lessons from the Liverpool Care Pathway

This paper describes three elderly patients who were admitted to hospital with aspiration pneumonia. They were kept nil by mouth (NBM) for a number of days, while being given intravenous hydration initially and enteral feeding subsequently. During that time they deteriorated and appeared to be dying, so the Liverpool Care Pathway (LCP) for the dying was used to support their care. Artificial nutrition and hydration were stopped. They quickly improved and the LCP was discontinued. Two of the patients deteriorated again on reintroduction of enteral feeding and/or intravenous fluids, only to improve a second time following withdrawal of feeding and fluids. Vulnerable elderly patients should not be made NBM except as a last resort. Clinicians should be alert to the possibility of refeeding syndrome and overhydration as reversible causes of clinical deterioration, particularly in frail elderly patients. Use of the LCP in these patients provided a unique opportunity to witness the positive effects of withdrawal of excessive artificial nutrition and hydration.

Improving outpatient services: the Southampton IBD virtual clinic

The follow-up of inflammatory bowel disease (IBD) patients is challenging due to the relapsing remitting nature of the diseases, the wide spectrum of severity and complexity as well as the need for monitoring of long-term complications and drug treatments. Conventional outpatient follow-up lacks flexibility for patients and there are competing pressures for clinic time. Alternative follow-up pathways include telephone clinics, self-management programmes or discharging patients. The IBD virtual clinic (VC) is a further option. Patients with an established diagnosis for >2 years, who have been stable for >1 year, do not have primary sclerosing cholangitis and who give their consent, are entered into the VC system. Two months before their annual follow-up is due patients are sent blood test forms and a simple questionnaire with an information sheet. If they meet any of the criteria on the questionnaire, they are asked to contact the IBD specialist nursing team to discuss their situation. The blood test results and the patient's database entry are reviewed to ensure that they are not due surveillance investigations. The patients and their GPs then receive a letter informing them of their management plan. We currently follow-up 20% of the Southampton IBD cohort using the VC. The VC system is an innovative, efficient and patient-responsive method for following up mild to moderate IBD. It is well liked by patients but is dependent on a well-maintained database with good integration of IT systems and requires both clerical and IBD nurse specialist support.

Improving outpatient services: the Southampton IBD virtual clinic

The follow-up of inflammatory bowel disease (IBD) patients is challenging due to the relapsing remitting nature of the diseases, the wide spectrum of severity and complexity as well as the need for monitoring of long-term complications and drug treatments. Conventional outpatient follow-up lacks flexibility for patients and there are competing pressures for clinic time. Alternative follow-up pathways include telephone clinics, self-management programmes or discharging patients. The IBD virtual clinic (VC) is a further option. Patients with an established diagnosis for >2 years, who have been stable for >1 year, do not have primary sclerosing cholangitis and who give their consent, are entered into the VC system. Two months before their annual follow-up is due patients are sent blood test forms and a simple questionnaire with an information sheet. If they meet any of the criteria on the questionnaire, they are asked to contact the IBD specialist nursing team to discuss their situation. The blood test results and the patient's database entry are reviewed to ensure that they are not due surveillance investigations. The patients and their GPs then receive a letter informing them of their management plan. We currently follow-up 20% of the Southampton IBD cohort using the VC. The VC system is an innovative, efficient and patient-responsive method for following up mild to moderate IBD. It is well liked by patients but is dependent on a well-maintained database with good integration of IT systems and requires both clerical and IBD nurse specialist support.

Malnutrition is dangerous: The importance of effective nutritional screening and nutritional care

In July 2010, the Government published the White Paper Equity and Excellence: Liberating the NHS, which places a strong emphasis on patient safety, sets the long-term vision for the NHS and describes a coherent framework of reform to deliver health care amongst the best in the world. Good nutritional care is a prerequisite of safe care and hence fundamental to the achievement of this vision, especially for vulnerable individuals. This article outlines the prevalence and costs associated with malnutrition * and the impact of malnutrition on patient safety within the context of the current NHS reforms. It concludes with guidance for clinicians and senior managers which, where fully implemented, will facilitate good nutritional care and ensure compliance to nutritional guidelines, standards and legislation including the regulations relating to nutrition as set out in the Health and Social Care Act 2008 (Regulated Activities) Regulations 2009 and the Care Quality Commission (Registration) Regulations 2009.

Malnutrition and nutrition support in patients with liver disease

Liver disease, especially alcohol related, is increasingly common and is often accompanied by malnutrition as a result of reduced intake, absorption, processing and storage of nutrients. An increase or alteration in metabolic demands also occurs and some patients have high nutrient losses. Malnutrition in all forms of liver disease is associated with higher rates of mortality and morbidity but it is often under recognised and under treated despite the fact that appropriate treatment can improve outcomes. In this review, the causes, consequences and assessment of nutritional status in patients with liver disease are examined, and an approach to best treatment is proposed.

Protein and the critically ill; do we know what to give?

The National Institute for Health and Clinical Excellence (NICE) has recommended that nutrition support in seriously-ill or injured patients should start at 50% of the estimated target energy and protein needs. This recommendation has caused some concern, since taking the NICE approach leads to these sick individuals receiving an initial N provision of only 0.12 g N/kg per d, as opposed to levels of approximately 0.25 g N/kg per d that have been widely recommended by other expert groups. The basis of the recommendation for higher levels of N provision is that feeding at levels of >/=0.25 g N/kg per d reduces the inevitable net N loss of catabolism and hence minimises overall lean tissue wasting. However, although it has always been assumed that better N balance must equate with better outcome, there are teleological arguments that question the wisdom of providing more N to sicker patients and studies that imply that best N balance might not equate with best clinical progress. Furthermore, current evidence suggests that in most critical illness low initial intakes of both energy and N lead to improved survival. It therefore seems logical to aim, in the first instance, to feed the seriously ill at only modest levels. Further research is required to determine whether lower-energy higher-N feeding would prove better or worse than this approach in terms of clinical benefit rather than just better N retention. Investigations to explore the use of feeds that are specifically designed to match the amino acid needs of illness are also required.

Impact of oedema on recovery after major abdominal surgery and potential value of multifrequency bioimpedance measurements

Background

The consequences of generalized oedema following major abdominal surgery are under-recognized, and its causes are poorly understood.

Methods

Thirty-eight patients (21 men and 17 women) were observed for the occurrence of oedema after major abdominal surgery. Oedema formation was related to fluid balance, changes in whole-body bioimpedance (Z) measured at four frequencies (5, 50, 100 and 200 kHz), and clinical outcome.

Results

The 20 patients who developed oedema were older than those who did not (mean(s.d.) 73(9) versus 63(14) years; P = 0·007). Fluid intake over the first 5 days after surgery was similar in both groups, but those with oedema excreted less total fluid (16·9(2·4) versus 19·7(3·5) litres; P = 0·022). Oedema was associated with a delay in tolerating solid food (P = 0·001) and opening bowels (P = 0·020), a prolonged hospital stay (median 17 (range 8–59) versus 9 (range 4–27) days; P = 0·001) and more postoperative complications (13 of 20 versus four of 18 patients; P = 0·011). The preoperative ratio of whole-body impedance at 200 kHz to that at 5 kHz was higher in those who subsequently developed oedema (0·81(0·03) versus 0·78(0·02); P = 0·015).

Conclusion

The development of oedema after major abdominal surgery is associated with increased morbidity. Age and reduced ability to excrete administered fluid load are significant aetiological factors and bioimpedance analysis can potentially identify patients at risk.

Malnutrition in hospital outpatients and inpatients: prevalence, concurrent validity and ease of use of the 'malnutrition universal screening tool' ('MUST') for adults

The 'malnutrition universal screening tool' ('MUST') for adults has been developed for all health care settings and patient groups, but ease of use and agreement with other published tools when screening to identify malnutrition requires investigation. The present study assessed the agreement and the prevalence of malnutrition risk between 'MUST' and a variety of other tools in the same patients and compared the ease of using these tools. Groups of patients were consecutively screened using 'MUST' and: (1) MEREC Bulletin (MEREC) and Hickson and Hill (HH) tools (fifty gastroenterology outpatients); (2) nutrition risk score (NRS) and malnutrition screening tool (MST; seventy-five medical inpatients); (3) short-form mini nutritional assessment (MNA-tool; eighty-six elderly and eighty-five surgical inpatients); (4) subjective global assessment (SGA; fifty medical inpatients); (5) Doyle undernutrition risk score (URS; fifty-two surgical inpatients). Using 'MUST', the prevalence of malnutrition risk ranged from 19-60% in inpatients and 30% in outpatients. 'MUST' had 'excellent' agreement (kappa 0.775-0.893) with MEREC, NRS and SGA tools, 'fair-good' agreement (kappa 0.551-0.711) with HH, MST and MNA-tool tools and 'poor' agreement with the URS tool (kappa 0.255). When categorisation of malnutrition risk differed between tools, it did not do so systematically, except between 'MUST' and MNA-tool (P=0.0005) and URS (P=0.039). 'MUST' and MST were the easiest, quickest tools to complete (3-5 min). The present investigation suggested a high prevalence of malnutrition in hospital inpatients and outpatients (19-60% with 'MUST') and 'fair-good' to 'excellent' agreement beyond chance between 'MUST' and most other tools studied. 'MUST' was quick and easy to use in these patient groups.

Early hormonal therapy stabilizes hemodynamics during donor procurement

BACKGROUND

Hemodynamic instability has been implicated in the loss of otherwise transplantable organs. We examined the hypothesis that administration of hormonal therapy early during donor management would stabilize hemodynamics and increase the number of organs procured.

METHODS

We retrospectively analyzed 133 consecutive donor records from a single organ procurement organization. Controls (C) received no early hormonal therapy. A steroid group (S) received methylprednisolone only and a combination hormonal therapy group (CH) received thyroxine, methylprednisolone, dextrose, and insulin at the start of donor management (t(0h)). Adrenergic support was adjusted to maintain mean arterial blood pressure (MAP) at > or =60 mm Hg. Doses of adrenergic agents were assessed at t(0h), 4 hours (t(4h)), and just prior to procurement (t(proc)).

RESULTS

Baseline characteristics were similar in all groups. Dosages of adrenergic agents decreased over time in all groups. A significant decrease in adrenergic requirements was seen in the CH group compared with the C group at t(4h) and t(proc). A trend toward decreased adrenergic requirements was noted in S compared with C at t(4h) and t(proc). Slightly more total organs were procured from S and CH compared with C.

CONCLUSIONS

Significantly less adrenergic support was required with early use of CH. A similar (although nonsignificant) reduction was seen with S. The benefit(s) of CH vs corticosteroids alone remains uncertain and requires further study.

Methods for the stable isotopic analysis of chlorine in chlorate and perchlorate compounds

Chlorate and perchlorate compounds, used as herbicides, solid fuel propellants, and explosives, are increasingly recognized as pollutants in groundwater. Stable isotope characterization would permit both environmental monitoring of extent of remediation and forensic characterization. Stoichiometric reduction to chloride (greater than 98% yield), by Fe(II) for chlorate and alkaline fusion-decomposition for perchlorate, allows analysis by standard methods to give highly reproducible and accurate delta37Cl results (0.05/1000, 2 x standard error). Analysis of various compounds from different suppliers yielded delta37Cl values for chlorate samples near to +0.2/1000 (SMOC), but one has within-sample heterogeneity of 0.5/1000, possibly due to crystallization processes during manufacture. Results for perchlorate samples also are generally near +0.2/1000, but one is +2.3/1000 (SMOC). The initial results suggest that both forensic and environmental applications might be feasible.

Comparison of calcaneal ultrasound and DXA to assess the risk of corticosteroid-induced osteoporosis: a cross-sectional study

Patients on long-term oral corticosteroids have an increased risk of low bone mass and fragility fractures. Fracture risk rises soon after commencement of corticosteroid therapy and it is possible that these agents adversely influence bone architecture disproportionately to their effect on bone mass. The best means of assessing bone status in patients using corticosteroids remains uncertain, but quantitative ultrasound of the calcaneus may provide evidence of microarchitectural changes not detected by dual-energy X-ray absorptiometry (DXA). Patients with Crohn's disease have an increased risk of low bone mineral density (BMD), the etiology of which is multifactorial but includes corticosteroid use. We studied 118 consecutive patients with Crohn's disease, 21 of whom used continuous oral corticosteroids, 70 of whom were intermittent users, and 27 who had never used the drug. All patients received DXA of the lumbar spine, hip and calcaneus and quantitative ultrasound (QUS) of the calcaneus. The different techniques were compared using a femoral neck T-score < or = -1.5 as the threshold of corticosteroid-induced osteoporosis. When compared with the femoral neck T-score, there were no significant differences between the predictive values of lumbar spine DXA, calcaneal DXA or calcaneal QUS to identify low femoral neck BMD. However, the absolute T-score required to give similar discriminatory capacity to femoral neck T-score varied substantially (T= -0.81 to -1.5) between the different measurement techniques and sites.

Cloning and expression of the histo-blood group Pk UDP-galactose: Ga1beta-4G1cbeta1-cer alpha1, 4-galactosyltransferase. Molecular genetic basis of the p phenotype

The molecular genetic basis of the P histo-blood group system has eluded characterization despite extensive studies of the biosynthesis of the P(1), P, and P(k) glycolipids. The main controversy has been whether a single or two distinct UDP-Gal:Galbeta1-R 4-alpha-galactosyltransferases catalyze the syntheses of the structurally related P(1) and P(k) antigens. The P(1) polymorphism is linked to 22q11.3-ter. Data base searches with the coding region of an alpha4GlcNAc-transferase identified a novel homologous gene at 22q13.2 designated alpha4Gal-T1. Expression of full coding constructs of alpha4Gal-T1 in insect cells revealed it encoded P(k) but not P(1) synthase activity. Northern analysis showed expression of the transcript correlating with P(k) synthase activity and antigen expression in human B cell lines. Transfection of P(k)-negative Namalwa cells with alpha4Gal-T1 resulted in strong P(k) expression. A single homozygous missense mutation, M183K, was found in six Swedish individuals of the rare p phenotype, confirming that alpha4Gal-T1 represented the P(k) gene. Sequence analysis of the coding region of alpha4Gal-T1 in P(1)+/- individuals did not reveal polymorphisms correlating with P(1)P(2) typing.

Long-term maintenance of weight loss following supplemented fasting

One hundred two obese subjects were evaluated 2-3 years following treatment in a combined behavior therapy and very low calorie diet (VLCD) program. Average weight loss after VLCD was 27.2 kg; average weight loss at follow-up was 11.3 kg. Subjects who reported high levels of exercise were more successful in maintaining weight loss (17.5 kg at follow-up) than were those who exercised only moderately (9.3 kg), or not at all (5.6 kg). Enrolling in a weight loss maintenance program also minimized weight regain. Subjects who participated in maintenance for more than 8 months sustained more average weight loss at follow-up (19.1 kg) than did subjects who participated for 8 months or less (10.6 kg), or subjects who did not participate in maintenance (6.6 kg).

Dual analyte immunoassay in neural tube defect and Down's syndrome screening: results of a multicentre clinical trial

We report a multicentre clinical field trial of a novel dual analyte enzyme immunoassay method for the simultaneous measurement of alpha-fetoprotein (AFP) and free beta-human choriogonadotropin (hCG) in the same microtitre well. The assay was shown to have good technical performance in the hands of all trial centres, with between assay coefficients of variation better than 10% for both analyte across the whole of the assay ranges. The method compared well with single analyte measuring procedures and produced acceptable performance as judged by external quality assurance criteria. Recovery of added analyte and analyte dilution curves also showed acceptable performance. In clinical evaluation of a large set of neural tube defect cases, good clinical discrimination from unaffected cases was observed using AFP. With over 150 Down's syndrome cases, the combination of AFP and free beta hCG confirmed the high detection rates achievable using this marker combination, with detection rates in excess of 70% in early gestation. We conclude that the combination of clinically superior markers coupled with technologically innovative assay design will lead to more efficient Down's screening programmes.

A specific type of ganglioside as a modulator of insulin-dependent cell growth and insulin receptor tyrosine kinase activity. Possible association of ganglioside-induced inhibition of insulin receptor function and monocytic differentiation induction in HL-60 cells

Insulin-dependent cell growth has been correlated with insulin receptor function, particularly receptor-associated kinase activity, in in vitro studies. The insulin-dependent phosphorylation of the 95-kDa receptor subunit was clearly inhibited, in a concentration-dependent manner, by the presence of unbranched neolacto series gangliosides having a NeuAc2----3Gal terminus, particularly 2----3-sialosylparagloboside (2----3SPG; IV3NeuAc-nLc4), but not by other gangliosides with a NeuAc2----6Gal terminus or by branched neolacto series gangliosides (e.g. G10). Such inhibition of phosphorylation was minimal with ganglio series gangliosides and negligible with sphingosine, neutral glycolipids, or sulfatide. 2----3SPG did not affect insulin binding to the insulin receptor. Insulin-dependent cell growth and its inhibition by 2----3SPG were observed in three human cell lines so far tested: lymphoid cell line IM9, promyelocytic leukemia cell line HL-60, and erythroleukemia cell line K562. Since IM9 cells contain a much higher quantity of insulin receptor than do HL-60 or K562 cells, insulin-dependent receptor phosphorylation and its inhibition by 2----3SPG in intact cells were clearly observed with IM9 cells. Receptor phosphorylation in intact cells was inhibited when cells were preincubated in the presence of 2----3SPG. Insulin-dependent growth of HL-60 and K562 cells was also inhibited by prolonged culture (96-144 h) with exogenous 2----3SPG. Subsequent to the inhibition of insulin-dependent HL-60 cell growth, a remarkable phenotypic transformation was observed, i.e. changes in morphology, enzymes, and cell-surface markers to those characteristic of monocytes. The level of 2----3SPG in HL-60 cells increased when cells were cultured with 1 alpha,25-dihydroxyvitamin D3 to the same degree seen in cells cultured with 5 microM 2----3SPG. Both these treatments led to inhibition of insulin-dependent cell growth, followed by induction of monocytic differentiation. Thus, the cellular level of 2----3SPG may modulate insulin-dependent cell growth and define the lineage specificity of differentiation through modulation of receptor-associated kinase activity.

Cellular and humoral mediators of sepsis syndrome

The story of mediators in sepsis syndrome is developing extremely rapidly and continues to unfold. This discussion has focused on those areas most studied and those that have the greatest clinical implications in the context of current knowledge. There are a number of mediators under active investigation that have not been reviewed here because their discussion is beyond the scope of this article. Just how all the pieces of the intricate cascade of events ultimately fit together is yet to be seen. However, the availability of important probes, such as cyclooxygenase inhibitors, TNF, anti-TNF, IL1, anti-IL1, anti-proteases, antioxidants, and antiendotoxin, is allowing major progress to be made in a short period of time. Transferring this knowledge to the bedside and everyday clinical practice is a slower process, but the prospects are bright for innovative new therapies for sepsis syndrome, septic shock, and the multiple organ failure associated with these clinical entities.