Microsurgical limb reconstruction in the non-concordant patient

Substance misuse is common in patients undergoing limb reconstruction secondary to open fractures and fracture related infection. This group risk breaching the social contract with their treating team through reduced engagement with perioperative care. Potential problems include limited social support, intravenous access, analgesia and withdrawal. These factors may negatively influence the range of treatments offered to this group. We aimed to establish the prevalence and outcomes of the problematically non-concordant cohort in our limb reconstruction population, who we aim to treat equitably even where non-concordance is suspected pre-operatively. A retrospective study was performed using our prospectively collected free flap limb reconstruction database from December 2021-October 2023. Patient electronic health records were reviewed for demographics, perioperative details and outcomes. Eighty patients were identified, with 8 identified as problematically non-concordant (10%). All patients had a background of substance abuse; smoking (100%), alcohol (75%), IVDU (63%). Pre-operative non-concordance included absconding (43%), staff abuse (57%) and refusal of care (57%). Post-operative non-concordance included smoking (75%), mobilisation against instructions (75%), absconding (63%). No patients had free flap failure. Inpatient stay varied from 8-83 days, average 28.50% of patients did not attend follow-up. The expanding horizon of microsurgery means complex reconstruction is offered to a greater range of patients. Surgical teams should ensure that this service is offered equitably, individualising treatment plans to achieve the best outcomes. Risk of non-concordance is usually evident pre-operatively. We advise early involvement of substance misuse teams, discharge support and an understanding team to achieve good outcomes.

Correction: Musa et al. An Electrochemical Screen-Printed Sensor Based on Gold-Nanoparticle-Decorated Reduced Graphene Oxide-Carbon Nanotubes Composites for the Determination of 17-β Estradiol. Biosensors 2023, 13, 491

In the original publication [...].

A non-faradaic impedimetric biosensor for monitoring of caspase 9 in mammalian cell culture

Lower yields and poorer quality of biopharmaceutical products result from cell death in bioreactors. Such cell death is commonly associated with programmed cell death or apoptosis. During apoptosis, caspases are activated and cause a cascade of events that eventually lead to cell destruction. We report on an impedance spectroscopy measurement technique for the detection of total caspase-9 in buffer and complex fluids, such as cell culture media. Enhanced sensitivity is achieved by leveraging the physiochemical properties of zinc oxide and copper oxide at the electrode-solution interface. Characterisation of the biosensor surface was performed using scanning electron microscopy and indirectly using an enzyme-linked immunosorbent assay. The characteristic biomolecular interactions between the target analyte and specific capture probe of the biosensor are quantified using non-faradaic electrical impedance spectroscopy (nfEIS). The proof-of-concept biosensor demonstrated a detection limit of 0.07 U/mL (0.032 µM) in buffer. The sensor requires a low sample volume of 50 μL without the need for sample dilution facilitating rapid analysis. Using a luminescence-based assay, the presence of active caspase-9 was detected in the culture media following exposure to a pro-apoptotic agent. We envision that the caspase-9 biosensor will be useful as a cell stress screening device for apoptosis monitoring.

An Electrochemical Screen-Printed Sensor Based on Gold-Nanoparticle-Decorated Reduced Graphene Oxide-Carbon Nanotubes Composites for the Determination of 17-β Estradiol

In this study, a screen-printed electrode (SPE) modified with gold-nanoparticle-decorated reduced graphene oxide-carbon nanotubes (rGO-AuNPs/CNT/SPE) was used for the determination of estradiol (E2). The AuNPs were produced through an eco-friendly method utilising plant extract, eliminating the need for severe chemicals, and remove the requirements of sophisticated fabrication methods and tedious procedures. In addition, rGO-AuNP serves as a dispersant for the CNT to improve the dispersion stability of CNTs. The composite material, rGO-AuNPs/CNT, underwent characterisation through scanning electron microscopy (SEM), ultraviolet-visible absorption spectroscopy (UV-vis), Fourier-transform infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). The electrochemical performance of the modified SPE for estradiol oxidation was characterised using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The rGO-AuNPs/CNT/SPE exhibited a notable improvement compared to bare/SPE and GO-CNT/SPE, as evidenced by the relative peak currents. Additionally, we employed a baseline correction algorithm to accurately adjust the sensor response while eliminating extraneous background components that are typically present in voltammetric experiments. The optimised estradiol sensor offers linear sensitivity from 0.05-1.00 µM, with a detection limit of 3 nM based on three times the standard deviation (3δ). Notably, this sensing approach yields stable, repeatable, and reproducible outcomes. Assessment of drinking water samples indicated an average recovery rate of 97.5% for samples enriched with E2 at concentrations as low as 0.5 µM%, accompanied by only a modest coefficient of variation (%CV) value of 2.7%.

Modelling a dynamic magneto-agglutination bioassay

The process of developing an end-to-end model of a magneto-immunoassay is described, simulating the agglutination effect due to the specific binding of bacteria to paramagnetic particles. After establishing the properties of the dose-specific agglutination through direct imaging, a microfluidic assay was used to demonstrate changes in the magnetophoretic transport dynamics of agglutinated clusters via transient inductive magentometer measurements. End-to-end mathematical modelling is used to establish the physical processes underlying the assay. First, a modified form of Becker-Döring nucleation kinetic equations is used to establish a relationship between analyte dose and average cluster size. Next, Stokes flow equations are used to establish a relationship between cluster size and speed of motion within the fluid chamber. This predicts a cluster-size dynamic profile of concentration of PMPs versus time when the magnetic field is switched between the two actuated magnets. Finally, inductive modelling is carried out to predict the response of the magnetometer circuit in response to the dynamics of magnetic clusters. The predictions of this model are shown to agree well with the results of experiments, and to predict the shape of the dose-response curve.

Modeling Peptide Nucleic Acid Binding Enthalpies Using MM-GBSA

The binding enthalpies of peptide nucleic acid (PNA) homoduplexes were predicted using a molecular mechanics generalized Born surface area approach. Using the nucleic acid nearest-neighbor model, these were decomposed into sequence parameters which could replicate the enthalpies from thermal melting experiments with a mean error of 8.7%. These results present the first systematic computational investigation into the relationship between sequence and binding energy for PNA homoduplexes and identified a stabilizing helix initiation enthalpy not observed for nucleic acids with phosphoribose backbones.

National audit of non-melanoma skin cancer excisions performed by plastic surgery in the UK

A national, multi-centre audit of non-melanoma skin cancer excisions by plastic surgery.

127 ‘BONE HEALTH AND FRACTURE RISK ASSESSMENT IN COPD EXACERBATIONS DURING HOSPITALISATION- ROOM FOR IMPROVEMENT?’

Background

COPD increases the risk of osteoporosis and international guidelines recommend that such patients undergo fracture risk assessment, referral for densitometry and appropriate management. We aimed to identify if patients admitted to our hospital with COPD exacerbation underwent assessment and were prescribed bone protection medication.

Methods

All admissions with COPD exacerbation to an Irish level 2 hospital between July 2020 and July 2021 were identified. The discharge summaries were screened for information regarding the presence of fracture risk and bone health assessment. Discharge prescriptions were examined for calcium, vitamin d and anti-osteoporosis medications. Radiology reports were screened for fragility fractures.

Results

Between July 2020–2021, there were 3,840 presentations to the medical assessment unit. Forty-six patients were admitted with a diagnosis of COPD exacerbation, mean age 72 (56% female). Seventy eight percent were classified as having GOLD Stage D disease with 28% receiving long term oxygen therapy. Mean number of hospitalisations per year per patient was 1.91 ± 1.2. Forty-three percent had laboratory evidence of bone health assessment during admission. Only 50% of patients were discharged on vitamin d replacement; 22% on calcium supplementation and 4% on osteoporotic medications. Regarding previous fractures, 9% had evidence of fragility fracture described on radiology reports, this was not mentioned on any hospital discharge letter.

Conclusion

This study suggests that opportunities for bone health assessment and intervention may be under recognised in COPD patients. Ways to improve this may include proformas and visual aids to prompt assessment and documentation of bone health, further education to increase awareness and greater access to densitometry resources in the community. In conclusion, this study highlights that further attention to patients’ bone health assessment and commencement of appropriate treatment is warranted. Admission to hospital or clinic review for such patients provide important opportunities for intervention.

Propofol detection for monitoring of intravenous anaesthesia: a review

This paper presents a review of established and emerging methods for detecting and quantifying the intravenous anaesthetic propofol in solution. There is growing evidence of numerous advantages of total intravenous anaesthesia using propofol compared to conventional volatile-based anaesthesia, both in terms of patient outcomes and environmental impact. However, volatile-based anaesthesia still accounts for the vast majority of administered general anaesthetics, largely due to a lack of techniques for real-time monitoring of patient blood propofol concentration. Herein, propofol detection techniques that have been developed to date are reviewed alongside a discussion of remaining challenges.

Setting up a new microsurgical breast service in a non-tertiary hospital: Is it safe, and do outcomes compare to centres of excellence?

AIMS

Access to autologous reconstruction continues to be limited in some areas of the United Kingdom. This is, in part, due to the perceived difficulty offering this service outside of a large tertiary centre. We present our experience setting up a new microsurgical breast reconstruction service in a district hospital and compare our results to the published outcomes of large volume centres.

METHODS

Patient data were collected prospectively from the start of the service to date (July 2018- July 2020) with the capture of demographics, management, and outcomes. The BREAST-Q tool was used preoperatively and at a minimum of 3 months.

RESULTS

The first 40 patients undergoing DIEP reconstruction were included. Of these, 70% were immediate, mean age was 49 years (27-68) and BMI was 28.1 kg/m2 (22-32.5). In all, 50% had one or more co-morbidities other than breast cancer. Median length of stay was 3 days (2-6) with 75% of patients discharged on day 2 or 3. Ten patients' stay exceeded 3 days - mostly due to social reasons. Flap loss occurred in 1 patient (2.5%). Twenty-one patients developed complications (52%) within 90 days: seven Clavien-Dindo Grade I, two Grade II and ten Grade IIIb. Fat necrosis and mastectomy flap necrosis were the most common complications. Surgical intervention was higher in those needing adjuvant therapy. Patient-reported outcomes showed post-operative improvement across all domains except abdominal physical well-being at median 11.3 months.

CONCLUSIONS

We present the shortest published length of stay for unilateral DIEP reconstructions. We are the first paper to publish patient-reported outcomes following a breast microsurgical enhanced recovery protocol. We demonstrate how a new microsurgical service, utilising an enhanced recovery protocol and careful patient selection can immediately achieve outcomes comparable to well-established centres. There is no reason why all patients should not have access to microsurgical breast reconstruction locally.

Classification of the mechanism of toxicity as applied to human cell line ECV304

The objective of this study was to identify the pattern of cytotoxicity testing of the human cell line ECV304 using three techniques of an ensemble learning algorithm (bagging, boosting and stacking). The study of cell morphology of ECV304 cell line was conducted using impedimetric measurement. Three types of toxins were applied to the ECV304 cell line namely 1 mM hydrogen peroxide (H₂O₂), 5% dimethyl sulfoxide and 10 μg Saponin. The measurement was conducted using electrodes and lock-in amplifier to detect impedance changes during cytotoxicity testing within a frequency range 200 and 830 kHz. The results were analysed, processed and extracted using detrended fluctuation analysis to obtain characteristics and features of the cells when exposed to the each of the toxins. Three ensemble algorithms applied showed slightly different results on the performance for classifying the data set from the feature extraction that was performed. However, the results show that the cell reaction to the toxins could be classified.

A non-contact impedimetric biosensing system for classification of toxins associated with cytotoxicity testing

We report on a novel impedance spectroscopy measurement and data analysis technique for cytotoxicity testing. The technique combines non-contact measurement with real-time impedance data analysis based on the toxin dose dependency of the outputs, making it suitable for high throughput screening. A multi-electrode array was designed and fabricated such that a standard well plate could be positioned above the electrodes, negating the requirement for bespoke culture wells with integrated electrodes. For cytotoxicity testing, endothelial cells, type ECV304, within the wells were exposed to various concentrations of 3 toxins, dimethyl sulphoxide, cadmium chloride and saponin, which exhibit different modes of action on cells. Impedance spectra were recorded every 30 min over a 24 h period. From the spectra 'toxin maps' were produced which presented the correlation between impedance output and dose of toxin versus frequency and time. The results demonstrated characteristic toxin maps for each toxin and significantly differences between the three toxins studied. Using complementary measurement methods, we showed that these differences in toxin maps related to morphological and physiological changes in the cells due to the differing mode of action of each toxin.

A Copper Oxide/Zinc Oxide Composite Nano-Surface for Use in a Biosensor

In this study, biosensors based on zinc oxide–copper oxide composite nano-surfaces were prepared using a simple and inexpensive distributed colloidal technique. Combinations of mixed dispersions with volume ratios of 1:1, 1:2 and 2:1 ZnO:CuO were compared. The uniform nano-crystalline sensor surfaces on polyethylene terephthalate (PET) were analysed using scanning electron microscopy (SEM), Atomic Force Microscopy (AFM) and Raman Spectroscopy. The ZnO–CuO composite biosensor nano-surfaces showed a significantly increased impedimetric signal compared with pure ZnO nanocrystals, and the maximum output was achieved with a volume ratio of 1:2 ZnO/CuO. The antibody capture of C-reactive protein (CRP) on the nano-surfaces was used to demonstrate the enhanced signal generated with increasing amounts of CuO in the nano-surface.

The magnitude of Yo-Yo test improvements following an aerobic training intervention are associated with total genotype score

Recent research has demonstrated that there is considerable inter-individual variation in the response to aerobic training, and that this variation is partially mediated by genetic factors. As such, we aimed to investigate if a genetic based algorithm successfully predicted the magnitude of improvements following eight-weeks of aerobic training in youth soccer players. A genetic test was utilised to examine five single nucleotide polymorphisms (VEGF rs2010963, ADRB2 rs1042713 and rs1042714, CRP rs1205 & PPARGC1A rs8192678), whose occurrence is believed to impact aerobic training adaptations. 42 male soccer players (17.0 ± 1y, 176 ± 6 cm, 69 ± 9 kg) were tested and stratified into three different Total Genotype Score groups; "low", "medium"and "high", based on the possession of favourable polymorphisms. Subjects underwent two Yo-Yo tests separated by eight-weeks of sports-specific aerobic training. Overall, there were no significant differences between the genotype groups in pre-training Yo-Yo performance, but evident between-group response differentials emerged in post-training Yo-Yo test performance. Subjects in the "high" group saw much larger improvements (58%) than those in the 'medium" (35%) and "low" (7%) groups. There were significant (p<0.05) differences between the groups in the magnitude of improvement, with athletes in the "high" and medium group having larger improvements than the "low" group (d = 2.59 "high" vs "low"; d = 1.32 "medium" vs "low"). In conclusion, the magnitude of improvements in aerobic fitness following a training intervention were associated with a genetic algorithm comprised of five single nucleotide polymorphisms. This information could lead to the development of more individualised aerobic training designs, targeting optimal fitness adaptations.

A genetic-based algorithm for personalized resistance training

Association studies have identified dozens of genetic variants linked to training responses and sport-related traits. However, no intervention studies utilizing the idea of personalised training based on athlete's genetic profile have been conducted. Here we propose an algorithm that allows achieving greater results in response to high- or low-intensity resistance training programs by predicting athlete's potential for the development of power and endurance qualities with the panel of 15 performance-associated gene polymorphisms. To develop and validate such an algorithm we performed two studies in independent cohorts of male athletes (study 1: athletes from different sports (n = 28); study 2: soccer players (n = 39)). In both studies athletes completed an eight-week high- or low-intensity resistance training program, which either matched or mismatched their individual genotype. Two variables of explosive power and aerobic fitness, as measured by the countermovement jump (CMJ) and aerobic 3-min cycle test (Aero3) were assessed pre and post 8 weeks of resistance training. In study 1, the athletes from the matched groups (i.e. high-intensity trained with power genotype or low-intensity trained with endurance genotype) significantly increased results in CMJ (P = 0.0005) and Aero3 (P = 0.0004). Whereas, athletes from the mismatched group (i.e. high-intensity trained with endurance genotype or low-intensity trained with power genotype) demonstrated non-significant improvements in CMJ (P = 0.175) and less prominent results in Aero3 (P = 0.0134). In study 2, soccer players from the matched group also demonstrated significantly greater (P < 0.0001) performance changes in both tests compared to the mismatched group. Among non- or low responders of both studies, 82% of athletes (both for CMJ and Aero3) were from the mismatched group (P < 0.0001). Our results indicate that matching the individual's genotype with the appropriate training modality leads to more effective resistance training. The developed algorithm may be used to guide individualised resistance-training interventions.

The dual role of paramagnetic particles for integrated lysis and measurement in a rapid immunoassay for intracellular proteins

A novel, integrated lysis and immunoassay methodology and system for intracellular protein measurement are described. The method uses paramagnetic particles both as a lysis agent and assay label resulting in a rapid test requiring minimal operator intervention, the test being homogeneous and completed in less than 10 min. A design study highlights the critical features of the magnetic detection system used to quantify the paramagnetic particles and a novel frequency-locked loop-based magnetometer is presented. A study of paramagnetic particle enhanced lysis demonstrates that the technique is more than twice as efficient at releasing intracellular protein as ultrasonic lysis alone. Results are presented for measurements of intracellular prostate specific antigen in an LNCAP cell line. This model was selected to demonstrate the rapidity and efficiency of intracellular protein quantification. It was shown that, on average, LNCAP cells contained 0.43 fg of prostate specific antigen. This system promises an attractive solution for applications that require a rapid determination of intracellular proteins.

Use of External Magnetic Fields To Reduce Reaction Times in an Immunoassay Using Micrometer-Sized Paramagnetic Particles as Labels (Magnetoimmunoassay)

The paper presents a rapid immunoassay system capable of quantifying analyte in complex biological and environmental media. Antibody-coated micrometer-sized paramagnetic particles are used as labels in an assay in which they bind quantitatively with an analyte and capture antibody molecules immobilized on a polyester disk to form a sandwich assay. The assay is performed in a simple reaction vessel, and reactions between labels, analyte, and antibodies are accelerated by positioning magnets alternately above and below the vessel. The bound paramagnetic particles are quantified using a simple flat, spiral, coil located just below the polyester disk. The electronic circuitry associated with the coil uses components that are inexpensive and readily available. The coil has been designed to respond only to particles bound on the disk and not to unbound particles still in the test solution. Unbound particles are pulled away from the disk by the magnet before readings are taken. The use of the reaction vessel with the cardiac markers CRP and CKMB is described. No sample preparation or washing step is used in the assays, and results can be obtained in less than 3 min after introducing the sample into the vessel with sensitivities in the normal clinical range.

Conditions predisposing to maternal mortality in twins and singletons, US birth cohort 1989

Twin pregnancy is one of the most important conditions associated with increased perinatal mortality and morbidity. The consequences of twin pregnancy on the mother have not been explored in great detail. The aim of this study was to analyze the population-based data from the United States and delineate the various conditions of twin pregnancies which predispose to maternal mortality. Results of this study show that multiple pregnancy is strongly associated with maternal mortality and requires further analysis in order to prepare appropriate therapeutic and prophylactic protocols.

Fungal atopy in adult cystic fibrosis

This study set out to estimate the prevalence of atopy to a variety of common ubiquitous fungi, including A. fumigatus, in cystic fibrosis (CF), and to evaluate the investigations by which the diagnosis was made. Particular attention was paid to the usefulness of skin testing and immunoassays in detecting which patients had simple fungal atopy, and which patients were at high risk of developing allergic bronchopulmonary mycoses. This cross-sectional study included 21 adult CF patients and 20 matched controls. Serum samples were taken for the measurement of total serum IgE and specific serum IgE to nine common fungi. Immediate hypersensitivity skin prick testing to each of the fungi was also performed. Simple fungal atopy was described in subjects fulfilling the following criteria: total serum IgE > 100 KU l(-1) with specific radioimmunoassay > or = grade 1 to at least one fungus and a positive skin prick test (SPT) > or = 3 mm to the same fungus. 'High risk' for developing allergic bronchopulmonary mycosis (ABPM) was described in subjects fulfilling the following criteria: total serum IgE > 200 KU l(-1) with specific radioimmunoassay > or = grade 2 to at least one fungus and a positive skin prick test (SPT) > or = 6 mm to the same fungus. The adult CF group had a significantly higher total SPT score (P=0.005) and mean total serum IgE (P<0.05) than controls. Forty-three percent of CF patients fulfilled the criteria for fungal atopy to at least a single fungus. Over half this group had an atopic tendency to more than one fungus. Nineteen percent of the CF group were at least 'high risk' of developing ABPM. Skin prick testing is a better marker of fungal atopy and a better predictor of those adult CF patients at higher risk of developing ABPM than specific radioimmunoassay serum testing. There is a high prevalence of fungal atopy in the adult CF population. Total serum IgE and skin prick testing are good predictors of fungal atopy and help predict those at risk of developing ABPM in CF.

Functions of fission yeast orp2 in DNA replication and checkpoint control

orp2 is an essential gene of the fission yeast Schizosaccharomyces pombe with 22% identity to budding yeast ORC2. We isolated temperature-sensitive alleles of orp2 using a novel plasmid shuffle based on selection against thymidine kinase. Cells bearing the temperature-sensitive allele orp2-2 fail to complete DNA replication at a restrictive temperature and undergo cell cycle arrest. Cell cycle arrest depends on the checkpoint genes rad1 and rad3. Even when checkpoint functions are wild type, the orp2-2 mutation causes high rates of chromosome and plasmid loss. These phenotypes support the idea that Orp2 is a replication initiation factor. Selective spore germination allowed analysis of orp2 deletion mutants. These experiments showed that in the absence of orp2 function, cells proceed into mitosis despite a lack of DNA replication. This suggests either that the Orp2 protein is a part of the checkpoint machinery or more likely that DNA replication initiation is required to induce the replication checkpoint signal.

Farmer's lung in Ireland (1983-1996) remains at a constant level

A prospective study was undertaken by the Departments of Respiratory Medicine and Medical Microbiology at the Cork University Hospital, a. to investigate the epidemiology of Farmer's Lung (F.L.) in the Republic of Ireland (pop. 3.5 million), with special reference to the South Western Region of this country (pop. 536,000) and b. to assess any relationship between the prevalence/incidence of F.L. with climatic factors in South West Ireland, between 1983 and 1996. F.L. incidence remained constant throughout the 13 yrs studied both on a national and a regional basis. A significant relationship was also found between total rainfall each summer and F.L. incidence and prevalence over the following yr (p < 0.005) in South-West Ireland. The persistence of F.L. in Ireland at a constant level suggests that farmers' working environment and farm practices need to be improved.

Changing sex ratio in the United States, 1969-1995

OBJECTIVE

To determine if the sex ratio of live births in the United States has changed during the 27 years from 1969 through 1995.

DESIGN

Regression analysis of secular trends in sex ratios.

SETTING

Population-based data.

PATIENT(S)

Liveborn infants in the United States 1969-1995.

MAIN OUTCOME MEASURE(S)

Sex of liveborn infant.

RESULT(S)

The sex ratio (number of male births divided by number of female births) declined significantly among whites during the 27 years under study. Among black newborns, the sex ratio significantly increased during the same time period.

CONCLUSION(S)

These secular trends could not be explained by changing maternal or paternal age, or by changing proportions of specific birth orders. Possible explanations for the observed changes in sex ratio include random fluctuations in sex ratio over time, changes in demographic characteristics of the population (other than the characteristics controlled for in this analysis), and changes in frequency or timing of intercourse. Environmental exposures are unlikely to account for the observed trends.

Violence faced by staff in a learning disability service

This study explores the issue of violence experienced by staff in the learning disability service of an NHS Trust. Based on the literature review a questionnaire survey was sent to all staff employed in the Trust's learning disability service (n = 295). The questionnaire sought: background details of respondents; numerical incidences and types of violence experienced over the previous 12 months; reporting mechanisms; reactions to and impact of violence on individuals and their work; support received. Vignettes provide a rich picture of the types of violent incidences and their impact. The findings show that 81% of staff in the learning disability service had experienced violence in the previous 12 months. Many had numerous experiences of violence. New and inexperienced staff are particularly vulnerable. Training and support systems are, on the whole, limited. Support received from colleagues is generally regarded as more helpful than that of line management. To explore good practice elsewhere, semi-structured interviews were held with individuals working with potentially violent clients in organizations other than the learning disability service. Suggestions are offered for putting in place human resource strategies to reduce the incidences of violence and provide appropriate post-incident support for staff on a continuing basis.

Influenza vaccination in 22 developed countries: an update to 1995

This study expands and updates through 1995 our earlier report on influenza vaccine use in 18 developed countries. Five of the six countries with high levels of vaccine use in 1992 (> or = 130 doses/1000 population) showed little change or slight declines over the subsequent 3 years. The exception was the United States, where a new federal program for vaccination reimbursement for the elderly helped to increase vaccine distribution from 144 to 239 doses/1000 population. The six countries with medium levels of vaccine use in 1992 (76-96 doses/1000 population) increased to > or = 100 doses/1000 population by 1995. Among the six low-use countries in 1992 (< or = 65 doses/1000 population), only Finland showed substantial improvement (96 doses/1000 population) in 1995. Four new countries were added to the study. In Germany, vaccine use increased to 80 doses/1000 population in 1995, but in Ireland it remained at a low level (48 doses/1000 population). In Korea, vaccine use increased from 17 to 95 doses/ 1000 population during the period 1987-1995. In Japan, very high levels of vaccine use (approximately 280 doses/1000 population) in the early 1980s were associated with vaccination programs for school children. However, vaccine use fell precipitously when these programs were discontinued, and only 2 and 8 doses/1000 population were used in 1994 and 1995, respectively. In all 22 countries, higher levels of vaccine use were associated with vaccination reimbursement programs under national or social health insurance and were not correlated with different levels of economic development. Excluding Japan, in 1995 there was still a greater than fourfold difference between the highest and lowest levels of vaccine use among the other 21 countries in the study. Given its well established clinical effectiveness and cost-effectiveness, none of these countries has yet achieved the full benefits of its programs for influenza vaccination.

Birthweight, preterm births and neonatal mortality in Belgium and the United States

Belgium is known to have a lesser low birthweight rate and a lower infant mortality rate than the United States. We used previously unpublished data to show that beneath this comparison lies a more complicated picture. Singleton live birth certificates for 1986-87 were analysed. Despite a lower mean birthweight in Belgium (3360 g) than in the United States (3420 g), Belgium had fewer (4.9%) low birthweight infants than the US (5.9%) because of fewer preterm births (4.4 vs. 9.3%). Consistent with the excess of preterm births in the US, the residual distribution of birthweight was smaller in Belgium (2.2% vs. 3.1%). Whereas neonatal mortality was 4.8/1000 in Belgium and 5.6/1000 in the US, birthweight-specific neonatal mortality was higher in Belgium. The challenge for Belgium is to improve the survival of newborns regardless of their birthweight. In the US, the task is to eliminate the excess of small preterm infants.

Birth weight and perinatal mortality. A comparison of the United States and Norway

OBJECTIVE

To compare perinatal mortality in the United States and Norway, using a new analytic approach based on relative birth weight.

DESIGN

Comparison of linked birth and perinatal death records for US and Norwegian births from 1986 through 1987, the most recently available 2-year period.

SETTING

Norway and the United States.

PARTICIPANTS

A total of 7,445,914 US births and 105,084 Norwegian births.

INTERVENTIONS

None.

MAIN OUTCOME MEASURE

Perinatal weight-specific mortality after adjustment for each country's own mean birth weight.

RESULTS

The higher rate of perinatal death in the United States compared with Norway is due to an excess of preterm deliveries in the United States. Low-weight, preterm births comprise 2.9% of US births compared with 2.1% of Norwegian births. If the United States could eliminate this slight excess of preterm delivery, perinatal mortality in the United States would decrease to the level in Norway. Unexpectedly, the survival of newborns at any given birth weight is virtually the same in the United States and Norway when newborns' birth weights are considered relative to their own nation's mean weight.

CONCLUSIONS

Low rates of perinatal mortality in the Scandinavian countries have usually been attributed to the heavier weights of their newborns. Higher mortality among US infants is in fact due entirely to a small excess of preterm deliveries. The lighter weights of US newborns at term appear not to affect perinatal survival. Furthermore, the apparent survival advantage of low-weight US newborns (used by policymakers as evidence of superior US intensive neonatal care) may be at least partly an artifact. When weight-specific mortality rates are adjusted to relative birth weight, low-weight newborns have the same survival in Norway as in the United States. The prevention of excess mortality among US infants depends on the prevention of preterm births, not on changes in mean birth weight.

Glucocorticoids down-regulate beta 1-adrenergic-receptor expression by suppressing transcription of the receptor gene

The expression of beta 2-adrenergic receptors is up-regulated by glucocorticoids. In contrast, beta 1-adrenergic receptors display glucocorticoid-induced down-regulation. In rat C6 glioma cells, which express both of these subtypes of beta-adrenergic receptors, the synthetic glucocorticoid dexamethasone stimulates no change in the total beta-adrenergic receptor content, but rather shifts the beta 1:beta 2 ratio from 80:20 to 50:50. Radioligand binding and immunoblotting demonstrate a sharp decline in beta 1-adrenergic receptor expression. Metabolic labelling of cells with [35S]-methionine in tandem with immunoprecipitation by beta 1-adrenergic-receptor-specific antibodies reveals a sharp decline in the synthesis of the receptor within 48 h for cells challenged with glucocorticoid. Steady-state levels of beta 1-adrenergic-receptor mRNA declined from 0.47 to 0.26 amol/microgram of total cellular RNA within 2 h of dexamethasone challenge, as measured by DNA-excess solution hybridization. The stability of receptor mRNA was not influenced by glucocorticoid; the half-lives of the beta 1- and beta 2-subtype mRNAs were 1.7 and 1.5 h respectively. Nuclear run-on assays revealed the basis for the down-regulation of receptor expression, i.e. a sharp decline in the relative rate of transcription for the beta 1-adrenergic-receptor gene in nuclei from dexamethasone-treated as compared with vehicle-treated cells. These data demonstrate transcriptional suppression as a molecular explanation for glucocorticoid-induced down-regulation of beta 1-adrenergic receptors.

Alcohol and cigarette use in a pregnant Irish population

One hundred women were selected at random and interviewed. All were postnatal. The object was to establish the level of alcohol and cigarette consumption and the level of knowledge to potential adverse effects. Of the 100 women interviewed 89% drank prior to pregnancy, six drank between 100-120 grams/week and 19 drank > 120 grams/week. 11 women stopped drinking when they became pregnant. In the group which drank 100-120 grams/week, 66% decreased their alcohol consumption considerably ie > 100 grams/week while pregnant, while in the group which drank > 120 grams/week only 15% decreased their alcohol consumption. 38 women binged on at least one occasion while 21 said they had binged on at least one occasion during the first trimester. 58% of women were aware of the harmful effects of alcohol during pregnancy. They compared with 93% who were aware of the harmful effects of smoking during pregnancy. Only 11% of women said a doctor had mentioned alcohol as harmful, while 57% said that a doctor had mentioned the hazard of smoking in pregnancy. The overall results show a general ignorance to the effects of alcohol consumption in pregnancy compared to the level of knowledge about smoking. The results also highlight the fact that doctors do not make patients aware of the effects of alcohol in pregnancy while they make an effort to educate people about the problems of smoking during pregnancy.

High-efficiency expression of mammalian beta-adrenergic receptors in baculovirus-infected insect cells

Infection of a clonal isolate of Spodoptera frugiperda cells (Sf9) with a baculovirus expression vector harboring the cDNA encoding the beta-adrenergic receptor resulted in a high efficiency expression. At 48 hr post-infection, the level of expression of beta-adrenergic receptors was approximately 12 million/cell. Specific activities of crude lysates of infected Sf9 cells were approximately 30 pmol/mg of protein, 5-fold greater than those of membranes of high-expressor Chinese hamster ovary cells stably transfected with an SV-40 expression vector. One liter of infected Sf9 cells expresses 20-40 nmol of receptor. Autoradiography of membranes incubated with the beta-adrenergic antagonist [125I]iodoazidobenzylpindolol, photolyzed, and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed 46,000- (presumably unglycosylated) and 48,000-Mr peptides for Sf9 cells as compared to approximately 65,000-Mr for Chinese hamster ovary cells. The baculovirus Sf9 system provides high-efficiency expression of receptor sufficient to permit physicochemical analyses.

Immune-related alterations in aged gut-associated lymphoid tissues in mice

To study whether senescence-induced changes in the gut-associated lymphoid tissue (GALT) are mainly quantitative, several parameters were examined in three age groups of BALB/c mice (1-2, 12-14, and 24-28 months old). A substantial senescence-associated decline in the number of lymphoid cells was found in the mesenteric lymph nodes (MLN) and spleen (SPN), and especially in the Peyer's patches (PP), but not in the lamina propria (LP). The distribution of lymphocyte subsets in these tissues was also altered with an absolute reduction of T cells--in particular, a L3T4+ helper/inducer T-cell marker-bearing subset. These changes were most remarkable in PP, followed by MLN. The in vitro proliferative reactivity and the production of each isotype-specific immunoglobulin (Ig) by PP, MLN, and SPN were profoundly affected when T-cell-dependent (Td) B-cell mitogens were used, but minimally affected when T-cell-independent (Ti) B-cell mitogens were used. The isotype-specific Ig content of small-intestinal perfusates was also influenced by aging, but only to a minor extent, as exemplified by a decrease in IgA levels in the fasting condition. Thus, despite the defects in the quantity and distribution of lymphocytes in aged PP and MLN, the finding of little change in the total amount of secreted IgA in aged intestine suggests that gut IgA-mediated luminal immune responses could remain nearly unaltered with senescence. The constancy of intraluminal IgA levels could be of physiological significance in host defense at the gut mucosal surface in aged mice.

Impaired non-specific suppressor-inducer T-cell activity in aged murine Peyer's patches, which can be corrected largely by IL-2 in vitro

To shed further light on the mechanism of age-associated T-cell-mediated immunoregulatory alterations in gut non-specific mucosal immune responses, we studied in vitro the function of a variety of concanavalin A (Con A)-activated immunoregulatory T-cell subsets derived from aged murine Peyer's patches (PP) (BALB/c > 24 months old) in the production of class-specific immunoglobulins (Ig) by young (5-8 months old) lipopolysaccharide (LPS)-activated PP B cells. The in vitro induction of Con A-activated PP helper (Th) [L3T4+ Lyt-2- Vicia villosa non-adherent (VV-)], suppressor (Ts) L3T4- Lyt-2+ (VV-), and contrasuppresor (Tcs) (L3T4+ Lyt-2- VV+) T cells were compared for the two age groups. The activities of aged PP-derived Ts and Tcs cells were greatly impaired, in contrast to minor defects in activity of the aged Th cells. The induction of effector Tcs cells, however, depended on the presence of functionally effective Ts cells. Recombinant IL-2 (rIL-2) could largely correct this impaired generation of aged Ts and Tcs cells. Next, we determined the activities of Ts inducer (Tsi) (L3T4+ Lyt-2- VV-) T cells in aged PP in vitro. The cell activity was considerably diminished in aged mice. Then, we tested in vitro whether rIL-2 could reconstitute the impaired generation of the aged non-specific Tsi cell. The function of the latter cell was largely restored by rIL-2. Thus, the major functional (intrinsic) defect present in immunocompetent T lymphocytes of murine aged PP was confined to the Tsi cell.

Immunoregulatory defects in murine aged Peyer's patches

Aging effect on immunoregulatory processes in Peyer's patches (PP) from BALB/c mice of 3-4 months and 24-28 months was studied in vitro. The magnitude of isotype-specific Ig production by aged or young PP B cells in co-culture with young or old fresh PP T cells strongly suggested that the suppressor activity of PP T cells was impaired in aged mice. Further studies on in vitro induction of concanavalin A-activated T helper cells, T suppressor-inducer cells and T suppressor cells from aged PP indicated that the generation of T suppressor cells was largely impaired, in contrast to a minor defect(s) in that of T helper cells. The findings obtained here at least suggest that in aged PP, a T suppressor-inducer cell subset appears to be more selectively impaired in the aging process than the other lymphocyte subpopulations, which possess minor intrinsic functional defects. Thus, these abnormal T and B cell responses in PP could be responsible for the senescence-associated gut mucosal immunologic dysfunction.