Bioactive Polyurethane-Poly(ethylene Glycol) Diacrylate Hydrogels for Applications in Tissue Engineering

Polyurethanes (PUs) are a highly adaptable class of biomaterials that are among some of the most researched materials for various biomedical applications. However, engineered tissue scaffolds composed of PU have not found their way into clinical application, mainly due to the difficulty of balancing the control of material properties with the desired cellular response. A simple method for the synthesis of tunable bioactive poly(ethylene glycol) diacrylate (PEGDA) hydrogels containing photocurable PU is described. These hydrogels may be modified with PEGylated peptides or proteins to impart variable biological functions, and the mechanical properties of the hydrogels can be tuned based on the ratios of PU and PEGDA. Studies with human cells revealed that PU-PEG blended hydrogels support cell adhesion and viability when cell adhesion peptides are crosslinked within the hydrogel matrix. These hydrogels represent a unique and highly tailorable system for synthesizing PU-based synthetic extracellular matrices for tissue engineering applications.

Broad responses and attitudes to having music in surgery (the BRAHMS study) - a South African perspective

BACKGROUND

Music is played in operating theatres (OTs) throughout the world, though controversy around its use exists. While some clinicians may find background music favourable to the theatre mood and a way to augment surgical performance, there is concern raised over its distracting and noise-creating properties.

METHODS

In this prospective observational study, between August and December 2021, 110 surgeons and registrars in South Africa responded to a survey investigating the way they use music, and their perceptions and attitudes towards its effect on the OT environment.

RESULTS

In this cohort, 66% were male, 29% were consultants and the most common age range was 30-39 years old. Eighty per cent of respondents reported that music was played at least "sometimes", with 74% reporting that they enjoyed it. Easy Listening was the most played and preferred genre followed by Top 40/Billboard hits. Overwhelmingly, respondents reported that background music in the OT improved temperament, focus, mood, and performance, though over a quarter felt it worsened communication. Thirty-one per cent of respondents reported that the choice of music depended on the type of operation, and 70% would turn music down or off during crises. Those who enjoyed music in their spare time were significantly more likely to enjoy music in the OT and perceive it positively.

CONCLUSION

This study provides a window into the surgeons' use of and attitudes to intraoperative music in South Africa. While overall, music is viewed positively by this cohort, some concerns remain regarding communication and distractedness. Further interventional and qualitative studies would be useful.

Significantly improved outcomes – both in retention and CGI scores - using Long Acting Buprenorphine (LAB-Buvidal) versus treatment as usual for Opioid Dependence in Wales during the Pandemic

Introduction

We have been using LAB (Buvidal) in Cardiff after its pandemic use was funded by Welsh Government.

Objectives

We wished to review the benefits of introducing LAB (Buvidal) into treatment during the pandemic.

Methods

This service development review of the first 73 patients treated with LAB (24mg/96mg rapid titration Welsh protocol) was analysed using Kaplan-Meier survival curves.

Results

43 (58%) male, 30 (41%) female. <25years=1, 38 (52%) aged 25-40, 34 (47%) 40-55. Prior to LAB 14% (10 people) using Espranor, 8% (6) Buprenorphine, 28% (20) Methadone. 50% (36) illicit opiates (mainly Heroin). We had continuous data for patients for up to 9 months of LAB. Two stopped for non-discontinuation reasons: One wanted to detox, one died of natural causes (LAB-unrelated). Both were excluded from discontinuation rate analysis. 55 people have data for over a month. Of these, 11 discontinued treatment. 80% remained on LAB for 1 month or more [95%CI 67-90%]. Kaplan-Meier plots showed similar discontinuation rates when comparing different OST programmes or none prior to LAB, and comparing by age, sex and initial illness severity (CGI severity). These rates all far exceeded data for traditional OST. CGI scores dramatically improved, even at one week. By month 2 all scores “much improved” or “very much improved”.

Conclusions

Buvidal (LAB) has 80% retention rates, regardless of underlying prescribed/illicit opioid /demographics. The commonly held belief that those on heroin are further from Recovery than those more stable on OAD may be incorrect. LAB may be a more acceptable and useful first line therapy that other OSTs

Disclosure

Dr Melichar has provided consultancy work, presentations, training and chaired panel discussions for all the companies in this area in the UK and some outside the UK. Recent work includes Althea (UK), Britannia (UK), Camurus (UK and Global), Martindale (U

1515 A Survey on The Perceived Effect of Background Music on Intra-Operative Stress, Anxiety and Surgical Task Load On the Operating Surgeon

Introduction

Music is commonly played in operating theatres throughout the world though its use remains controversial. There is growing literature supporting the notion that playing background music can improve a surgeon’s task performance and reduce performance stress. We present findings from our survey of surgeons about their perceptions of the effect of intra-operative music on their stress levels.

Method

Surgeons and registrars from three different specialties – general, vascular, and paediatric surgery – in a single tertiary centre were surveyed on their views on the effect of music in theatre. Two instruments were used to assess parameters of stress: the modified 6-point state trait anxiety inventory (STAI-6) and the surgical task load index (SURG-TLX).

Results

There were 35 respondents across the three surgical specialties (78% response rate). Pop and “easy listening” were the most popular genres. A majority felt music improved their temperament (75%) and perceived stress (63%). 59% of respondents reported no to low perceived anxiety with music, compared with 31% reporting moderate and 9% high anxiety based on STAI-6 parameters. Regarding SURG-TLX parameters and music, respondents overall perceived feeling less anxious, rushed and mentally fatigued though more distracted.

Conclusions

Music is generally thought to have positive subjective effects on the theatre environment with regards to anxiety levels, temperament, perceived stress, and parameters within the surgical task load index. This is counterbalanced by a smaller group of respondents who felt that music can impair communication and increase distraction within theatre. Music used appropriately may reduce perceptions of stress in theatre.

504 Can Measuring Heart Rate Variability in The Operating Surgeon Provide Insight into Intra-Operative Stress? A Literature Review and Direction for Research

Introduction

Stress affects the internal environment of the operating surgeon. Examining ways to mitigate this could prove important to the health of both surgeon, and patients.

Heart rate variability (HRV) is emerging as a novel, validated measure of autonomic nervous system (ANS) function with developing accessible and non-invasive technologies. HRV parameters correlate to ANS function and can be used to measure responses to various stimuli.

Method

A search strategy was developed to identify 23 articles that matched inclusion criteria. These included data collected intra-operatively with ambulatory monitoring, in simulated settings and one systematic review.

Results

Several studies found increased sympathetic response in the operating surgeon – which correlates with subjective reporting of stress. Some studies compared variables; one study suggested that laparoscopic colorectal surgery caused higher mental strain than open, while another suggested higher stress in surgeons while teaching compared to when primary operator. There have been no comparative trials using HRV in surgeons.

Conclusions

We present a review of the growing literature regarding HRV measurement in surgeons. This novel tool is a promising avenue to provide psychophysiological insight into the operating surgeon. This could guide future research into optimising the theatre environment for intra-operative performance using controlled or in-situ design.

Skin biopsy utilization and melanoma incidence among Medicare beneficiaries

BACKGROUND

Melanoma incidence has increased in recent decades in the U.S.A. Uncertainty remains regarding how much of this increase is attributable to greater melanoma screening activities, potential detection bias and overdiagnosis.

OBJECTIVES

To use a cross-sectional ecological analysis to evaluate the relationship between skin biopsy and melanoma incidence rates over a more recent time period than prior reports.

METHODS

Examination of the association of biopsy rates and melanoma incidence (invasive and in situ) in SEER-Medicare data (including 10 states) for 2002-2009.

RESULTS

The skin biopsy rate increased by approximately 50% (6% per year) throughout this 8-year period, from 7012 biopsies per 100 000 persons in 2002 to 10 528 biopsies per 100 000 persons in 2009. The overall melanoma incidence rate increased approximately 4% (< 1% per year) over the same time period. The incidence of melanoma in situ increased approximately 10% (1% per year), while the incidence of invasive melanoma increased from 2002 to 2005 then decreased from 2006 to 2009. Regression models estimated that, on average, for every 1000 skin biopsies performed, an additional 5·2 (95% confidence interval 4·1-6·3) cases of melanoma in situ were diagnosed and 8·1 (95% confidence interval 6·7-9·5) cases of invasive melanoma were diagnosed. When considering individual states, some demonstrated a positive association between biopsy rate and invasive melanoma incidence, others an inverse association, and still others a more complex pattern.

CONCLUSIONS

Increased skin biopsies over time are associated with increased diagnosis of in situ melanoma, but the association with invasive melanoma is more complex.

Utilizing Participatory Mapping and GIS to Examine the Activity Spaces of Homeless Youth

Although previous studies have informed our understanding of certain aspects of youth homelessness, few studies have critically examined the spatial and social environments utilized by youth as they navigate life on the streets. This study employed participatory mapping and Geographic Information Systems (GIS) to examine the activity spaces of homeless youth as they relate to sense of community and psychological well-being. Participants were 28 youth experiencing homelessness in Portland, Oregon, USA. Results suggest that youth engage most frequently in service-related activities, and their activity participation is significantly associated with sense of community and psychological well-being. The utility of innovative participatory methods for better understanding the diverse experiences of homeless youth is discussed alongside examination of their practical implications.

Characterization of two cation diffusion facilitators NpunF0707 and NpunF1794 in Nostoc punctiforme

AIMS

To characterize genes involved in maintaining homeostatic levels of zinc in the cyanobacterium Nostoc punctiforme.

METHODS AND RESULTS

Metal efflux transporters play a central role in maintaining homeostatic levels of trace elements such as zinc. Sequence analyses of the N. punctiforme genome identified two potential cation diffusion facilitator (CDF) metal efflux transporters, Npun_F0707 (Cdf31) and Npun_F1794 (Cdf33). Deletion of either Cdf31or Cdf33 resulted in increased zinc retention over 3 h. Interestingly, Cdf31(-) and Cdf33(-) mutants showed no change in sensitivity to zinc exposure in comparison with the wild type, suggesting some compensatory capacity for the loss of each other. Using qRT-PCR, a possible interaction was observed between the two cdf's, where the Cdf31(-) mutant had a more profound effect on cdf33 expression than Cdf33(-) did on cdf31. Over-expression of Cdf31 and Cdf33 in ZntA(-) - and ZitB(-) -deficient Escherichia coli revealed function similarities between the ZntA and ZitB of E. coli and the cyanobacterial transporters.

CONCLUSIONS

The data presented shed light on the function of two important transporters that regulate zinc homeostasis in N. punctiforme.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study shows for the first time the functional characterization of two cyanobacterial zinc efflux proteins belonging to the CDF family.

Long lag times and high velocities in the motility of natural assemblages of marine bacteria

The motility characteristics of natural assemblages of coastal marine bacteria were examined. Initially, less than 10% of the bacteria were motile. A single addition of tryptic soy broth caused an increase in the motile fraction of cells but only after 7 to 12 h. Motility peaked at 15 to 30 h, when more than 80% of cells were motile. These results support the proposal that energy limits motility in the marine environment. Cell speeds changed more than an order of magnitude on timescales of milliseconds and hours. The maximum community speed was 144 (mu)m s(sup-1), and the maximum individual burst velocity was 407 (mu)m s(sup-1). In uniform medium, speed was an inverse function of tryptic soy broth concentration, declining linearly over 0.001 to 1.0%. In media where concentration gradients existed, the mean speed was a function of position in a spatial gradient, changing from 69 to 144 (mu)m s(sup-1) over as little as 15 to 30 (mu)m. The results suggest that marine bacteria are capable of previously undescribed quick shifts in speed that may permit the bacteria to rapidly detect and keep up with positional changes in small nutrient sources. These high speeds and quick shifts may reflect the requirements for useful motility in a turbulent ocean.

Clustering of marine bacteria in seawater enrichments

Seawater enrichments of marine bacteria clustered in 20- to 50-(mu)m-wide bands near air-water interfaces. The cells within the band travelled at up to 212 (mu)m s(sup-1) and at an average speed of 163 (mu)m s(sup-1). Mean cell speeds peaked mid-run at 187 (mu)m s(sup-1). At the end of the run, bacteria reversed direction rather than randomly reorienting. The duration of the stops during reversal was estimated at 18 ms, six to seven times shorter than that found in enteric bacteria. Cells hundreds of micrometers from the band travelled at half the speed of the bacteria in the band. The fastest isolate from the seawater enrichment was identified as Shewanella putrefaciens and had an average speed of 100 (mu)m s(sup-1) in culture. Air-water interfaces produced no clustering or speed changes in isolates derived from enrichments. Salinity and pH, however, both influenced speed. The speed and reversal times of the seawater enrichments indicate that the bacteria in them are better adapted for clustering around small point sources of nutrients than are either enteric or cultured marine bacteria.

High-power linearly-polarized single-frequency thulium-doped fiber Master-Oscillator Power-Amplifier

We report a high power narrow-linewidth source at approximately 2 microm based on a Tm-doped fiber distributed-feedback master-oscillator and three Tm fiber amplifier stages. The master-oscillator and first two amplifier stages were in-band pumped by Er,Yb fiber lasers operating at 1565 nm, and the final stage amplifier was cladding-pumped at 795 nm by two spatially-combined diode-stacks. The MOPA yielded 100 W of single frequency output at 1943 nm with a beam propagation factor (M(2)) of 1.25 and with a polarization extinction ratio of >94%. The output power was limited by thermally-induced damage in the final amplifier stage. The prospects for further power scaling are considered.

Broadband Tm-doped superfluorescent fiber source with 11 W single-ended output power

High-power operation of a cladding-pumped Tm-doped broadband superfluorescent fiber source in the two-micron wavelength regime is described. Predominately single-ended operation was achieved using a simple all-fiber geometry without the use of a high reflectivity mirror or fiber Bragg gratings. The source produced >11 W of single-ended amplified spontaneous emission output spanning the wavelength range from approximately 1930 nm to 1988 nm for a launched diode pump power of approximately 40 W at approximately 790 nm, corresponding to a slope efficiency of 38% with respect to launched pump power. The wavelength spectrum of the superfluorescent source spanned the range from approximately 1650 to 2100 nm with a bandwidth (FWHM) of > 100 nm for output power levels of < 20 mW.

Availability and use of emergency obstetric services: Kenya, Rwanda, Southern Sudan, and Uganda

The article summarises the baseline assessments of emergency obstetric care (EmOC) carried out in Uganda, Kenya, Southern Sudan, and Rwanda in 2003 and 2004.

OBJECTIVES

Our objectives were to: (1) set up program baselines on the availability and utilization of EmOC services in these countries; (2) identify gaps and obstacles in providing EmOC services; and (3) make recommendations to governments based on evidence generated.

METHODS

Data were collected from clinical record reviews, provider and client interviews, observations, and focus group discussions. Either random or universal sampling was applied in the selection of health facilities assessed. Local nurses and midwives participated in the data collection and, to some extent, data processing and analysis.

RESULTS

The coverage of basic EmOC services ranged 0-1.1/500,000 population compared to the UN-recommended level of 4/500,000. The coverage of comprehensive EmOC services ranged 0.5-4.3/500,000 compared to the recommended level of 1/500,000. Between 0.6% and 8.8% of all births took place in EmOC facilities, and 2.1% and 18.5% of all expected direct obstetric complications were treated. Cesarean section as a proportion of all births was between 0.1% and 1%. Shortage of trained staff especially mid-level providers, poor basic infrastructure such as lack of electricity and water supplies, inadequate supply of drugs and essential equipment, poor working conditions and staff morale, lack of communication and referral facilities, cost of treatment, and lack of accountability and proper management were identified as the main obstacles in providing 24-h quality EmOC services especially in remote and rural areas.

CONCLUSIONS

Lack of basic EmOC services limits women's access to life-saving services during obstetric complications. To reduce maternal mortality ratio the states and development partners need to focus their effort to improve the coverage, quality, and utilization of EmOC services through supportive national policy, effective program strategies, increased budget allocation to maternal health program, rural infrastructure development, and regular monitoring, and evaluation of progress.

Highly active antiretroviral therapy (HAART)-associated lactic acidosis: in vitro effects of combination of nucleoside analogues and protease inhibitors on mitochondrial function and lactic acid production

Lactic acidosis is a rare but potentially life-threatening and poorly understood sequelae among HIV-infected patients on highly active antiretroviral therapy (HAART). Mitochondrial DNA depletion and inhibition of respiratory complexes have been hypothesized to be involved in HAART-associated lactic acidosis. Although mitochondrial toxicity and increased plasma lactates are associated with long-term exposure to nucleoside analogue reverse transcriptase inhibitors (NRTI), reports of lactic acidosis are now emerging among HIV-infected patients exposed to combination therapy that includes not only NRTI but also protease inhibitors (PI). We therefore investigated the effects of clinically relevant NRTI and PI combinations on mitochondrial membrane potential, uncoupling of mitochondrial respiration from oxidative phosphorylation and lactic acid production. Our study demonstrated that treatment of HepG2 cells with a combination of nucleoside analogues and PI, decreased mitochondrial membrane potential (delta psi m) within 24 hr, followed by increased lactic acid production after 9 days of treatment. However, loss of delta psi m and increased lactates were not associated with mitochondrial uncoupling or ATP production. Our findings suggested that not only NRTI but also PI are capable of increasing lactic acid production in vitro, and probably involve early biochemical changes in mitochondrial function such as loss of mitochondrial membrane potential.

Field fluorometers as dispersed oil-in-water monitors

A laboratory study of the Turner Instrument flow-through models 10AU and 10 fluorometers was conducted to review their ability to measure real-time oil-in-water concentrations, to compare the results to other total petroleum hydrocarbon (TPH) procedures and to improve the understanding of the relationship of the fluorescence to the chemical composition of the oils. Comparison of the fluorometer results to standard infrared and gas chromatography laboratory procedures showed all methods capable of detecting and differentiating between small changes in oil concentration. The infrared and gas chromatography generated similar values while the fluorometer values were of the same order of magnitude but typically 20-80% higher. The chemical composition of the oils was determined by gas chromatographic techniques and compared to the signal outputs of the fluorometers. It was found that the fluorometer data could not be directly linked to the concentration of any specific aromatic hydrocarbon such as naphthalene or to the sum of the polycyclic aromatic hydrocarbon (PAH) compounds. Evidence suggests that the fluorescence signal is generated by a combination of PAH compounds. Also, the response of the fluorometers may also be influenced by the presence of volatile aromatic compounds such as benzene, toluene, ethyl benzene and xylene (BTEX) and C3-benzenes (BTEX + C3B) in combination with the PAH compounds.

Meso-portal bypass in children with portal vein thrombosis: rapid increase of the intrahepatic portal venous flow after direct portal hepatic reperfusion

BACKGROUND/PURPOSE

In children with portal vein (PV) thrombosis, hepatopetal portal flow can be restored by an innovative surgical procedure, the meso-portal-bypass (MPB), if the umbilical portion of the intrahepatic left PV and the superior mesenteric vein are patent. This is associated with resolution of symptoms related to extrahepatic portal hypertension (EHPH). However, no data are available yet on intrahepatic hemodynamic changes after MPB. The aim of this study was to evaluate morphologic adaptation and flow characteristics of the intrahepatic PV branches (ihPVb) after MPB.

METHODS

Prospective follow-up Doppler scans of the ihPVb were performed at 0.5 to 1, 3 to 6 and 12 months after MPB in 13 consecutive patients (2000-2002) and compared with preoperative findings.

RESULTS

Only small ihPVb were detected preoperatively on Doppler in 8 of 13 cases. Postoperatively (median follow up 12; range, 6 to 24 months), all 13 patients had patent MPB with hepatopetal flow, and ihPVb were easy to detect with satisfactory vessel diameters and flow velocities.

CONCLUSIONS

The preoperatively small ihPVb increase rapidly in diameter and hepatopetal flow velocity in patients benefiting from MPB. This correlates well with progressive resolution of their symptoms related to EHPH and reflects rapid adaptation of ihPVb.

Liver disease in children with cystic fibrosis

Identification, evaluation and treatment of liver disease are increasingly important challenges in children with cystic fibrosis (CF). Liver disease usually presents at puberty and is receiving more attention with improved life expectancy. The abnormal CF transmembrane regulator protein in the apical surface of the biliary epithelium causes the disease. Hyperviscous bile accumulates in the biliary tree causing cholangiocyte and hepatocyte injury, stimulating focal fibrosis. Fibrosis is thought to lead on to cirrhosis over a period of years, a process which is usually asymptomatic. Steatosis and biliary tree anomalies including cholecystitis also occur. Clinical signs of liver disease appear late, by which time cirrhosis may be established. Early diagnosis would allow interventions to be evaluated but there is no gold standard for screening. Currently, regular clinical assessment, measurement of liver enzymes, ultrasound and liver biopsy are all used to evaluate liver disease in CF. Bile acid therapy reverses many markers of the disease but there is no good evidence that progression to cirrhosis can be prevented. A few children with cirrhosis decompensate (demonstrated by falling plasma albumin or coagulopathy) but they do well with liver transplantation. Children with portal hypertension as the sole manifestation of CF liver disease can be effectively managed with a programme of variceal obliteration or porto-systemic shunts.

A REVIEW OF OIL-IN-WATER MONITORING TECHNIQUES

A comprehensive laboratory study of the Turner Instrument flow-through fluorometers was conducted to review their ability to measure real-time oil-in-water concentrations, to compare the results to alternative total petroleum hydrocarbon (TPH) procedures and to carry out supporting laboratory analysis in order to further understand the relationship of the fluorescent signal to the composition of the oils.

The model 10 AU was equipped with the long wavelength optical kit for crude oils while the model 10 was equipped with the short wavelength optical kit for diesel fuels and light refined oil products. Eight oils and the dispersant COREXIT®9500 were used. The oils were Alberta Sweet Mixed Blend crude oil (0% and 27% weathered), Prudhoe Bay crude oil (0% and 27% weathered), Bunker C fuel oil (0% and 8% weathered), and diesel fuel (0% and 37% weathered).

Efforts were made to establish a calibration procedure which was used to convert the real-time fluorometer data to oil concentration. Initial comparisons of the fluorometer results to standard infrared and gas chromatography laboratory procedures showed all methods capable of detecting and differentiating between small changes in oil concentration. The infrared and gas chromatography generated similar values while the fluorometer values were of the same order of magnitude but typically 20 to 80% higher.

An audit into homeless families in temporary accommodation

This article describes a clinical audit project undertaken in a number of hostels providing temporary housing for homeless families and individuals in Hinckley, Leicestershire. The audit, carried out over a 6-week period, aimed to collect information about the health and social needs of the residents in the hostels to determine whether an on-site dedicated health visiting service would be of any benefit to them. Family members housed in three council-run hostels were interviewed and a detailed questionnaire was completed. This was used to gather information about the facilities in the hostels, the nutritional and mental status and health and social needs of the residents, the uptake of childhood immunizations and child health surveillance. It also provided information about the resident families' contact with their family health visitor. Families were living in cramped conditions with shared facilities and no safe play areas for their children. The audit clearly demonstrated that the residents living in the hostels had a range of health problems similar to those described in the literature about the homeless. As a result of the audit, a number of recommendations were made which are discussed in this article.

Evaluation and validation of virus removal by ultrafiltration during the production of diaspirin crosslinked haemoglobin (DCLHb)

Virus retention during ultrafiltration through A/G Technology filter cartridges was investigated to characterize the removal process and validate the degree of virus titre reduction during the filtration of red blood cell haemolysates performed as part of the production of diaspirin crosslinked haemoglobin (DCLHb). When viruses were suspended in phosphate buffered saline solution, retention was greater with larger sized viruses and smaller filter pore size. Virus titre was maintained at starting levels in the filter retentate circuit during the course of filtration, suggesting that the virus removal mechanism is predominantly size exclusion. Evaluation of specific processing variables indicated that the retention of phiX174 virus was increased in the presence of red blood cell haemolysate or at high membrane crossflow rates and transmembrane pressures, while the retention of EMC virus was less sensitive to variations in these parameters. Using these results to design a validation protocol, log reduction values of >7.9 were demonstrated for the retention of human immunodeficiency virus, pseudorabies virus and bovine viral diarrhoea viruses, 7.6 for hepatitis A virus, and 4.2 for porcine parvovirus. It was also shown that the retention of viruses was maintained during repetitive use of the same filter cartridge.

Calcium supplements and colorectal adenomas. Polyp Prevention Study Group

Experimental and observational findings suggest that calcium intake may protect against colorectal neoplasia. To investigate this hypothesis, we conducted a randomized, double-blind trial of colorectal adenoma recurrence. Nine hundred thirty patients with a recent history of colorectal adenomas were randomly given calcium carbonate (3 gm daily; 1200 mg elemental calcium) or placebo, with follow-up colonoscopies one and four years after the qualifying examination. The main analysis focused on new adenomas found after the first follow-up endoscopy, up to (and including) the second follow-up examination. Risk ratios of at least one recurrent adenoma and ratios of the average numbers of adenomas were calculated as measures of calcium effect. There was a lower risk of recurrent adenomas in subjects assigned calcium. Eight hundred thirty-two patients had two follow-up examinations and were included in the main analysis; the adjusted risk ratio of one or more adenomas was 0.81 (95% CI 0.67 to 0.99); the adjusted ratio of the average numbers of adenomas was 0.76 (95% CI 0.60 to 0.96). Among subjects who had at least one follow-up colonoscopy, the adjusted risk ratio of one or more recurrent adenomas was 0.85 (95% CI 0.74 to 0.98). The effect of calcium seemed independent of initial dietary fat and calcium intake. No toxicity was associated with supplementation. These findings indicate that calcium supplementation has a modest protective effect against colorectal adenomas, precursors of most colorectal cancers.

Pramlintide, a synthetic analog of human amylin, improves the metabolic profile of patients with type 2 diabetes using insulin. The Pramlintide in Type 2 Diabetes Group

OBJECTIVE

To examine the effects of 4 weeks of subcutaneous administration of pramlintide, a synthetic analog of human amylin, on metabolic control in patients with type 2 diabetes using insulin.

RESEARCH DESIGN AND METHODS

Serum fructosamine, HbA1c, and fasting plasma lipids were measured in 203 patients in a randomized double-blind placebo-controlled parallel-group multicenter trial using doses of 30 micrograms q.i.d., 60 micrograms t.i.d., and 60 micrograms q.i.d.

RESULTS

Statistically significant reductions in serum fructosamine concentrations were observed in the pramlintide 30 micrograms q.i.d. group (17.5 +/- 4.9 mumol/l, P = 0.029), the pramlintide 60 micrograms t.i.d. group (24.1 +/- 4.9 mumol/l, P = 0.003), and the 60 micrograms q.i.d. group (22.6 +/- 4.1 mumol/l, P = 0.001) compared with the placebo group (3.5 +/- 3.8 mumol/l). There were also statistically significant shifts in the proportion of patients with an abnormal serum fructosamine concentration at baseline that normalized at week 4 within the pramlintide 60 micrograms t.i.d. group and the 60 micrograms q.i.d. group. Consistent with the fructosamine results, there were statistically significant reductions in HbA1c in the pramlintide 30 micrograms q.i.d. group (0.53 +/- 0.07%, P = 0.0447), the pramlintide 60 micrograms t.i.d. group (0.58 +/- 0.07%, P < 0.0217), and the pramlintide 60 micrograms q.i.d. group (0.51 +/- 0.08%, P = 0.0242) compared with the placebo group (0.27 +/- 0.08%). Total cholesterol concentrations were also statistically significantly reduced in both the pramlintide 60 micrograms t.i.d. group (8.4 mg/dl, P < 0.01) and 60 micrograms q.i.d. group (10.5 mg/dl, P < 0.01) compared with placebo (1.2 mg/dl). Body weight decreased in both of the pramlintide 60 micrograms groups, but the trend did not achieve statistical significance. The incidence of hypoglycemia was similar in all treatment groups.

CONCLUSIONS

Reductions in serum fructosamine, plasma total and LDL cholesterol concentrations, and HbA1c support the hypothesis that pramlintide may improve metabolic control in patients with type 2 diabetes using insulin.

Effects of 4 weeks' administration of pramlintide, a human amylin analogue, on glycaemia control in patients with IDDM: effects on plasma glucose profiles and serum fructosamine concentrations

The effects of 4 weeks' administration of pramlintide, an analogue of the human hormone amylin, on blood glucose control in 215 patients with insulin-dependent diabetes mellitus were examined in a 4-week, randomized, double-blind, placebo-controlled, parallel-group trial. Pramlintide was administered subcutaneously prior to meals in four dosing regimens: 30 microg four times per day (breakfast, lunch, dinner, and evening snack), 30 microg three times per day (breakfast, lunch and dinner [BLD]), 30 microg three times per day (breakfast, dinner and evening snack [BDS]), and 60 microg twice per day (breakfast and dinner). After 4 weeks of pramlintide 30 microg four times per day administration, there was a statistically significant reduction in the mean 24 h plasma glucose concentration when compared to placebo (-1.4 +/- 0.5 vs 0.3 +/- 0.5 micromol/l, p = 0.009). Serum fructosamine concentrations were reduced 62 +/- 10 micromol/l in the pramlintide 30 mg four times per day group, 43 +/- 7 micromol/l in the pramlintide 30 microg three times per day (BLD) group, 47 +/- 6 micromol/l in the pramlintide 30 microg three times per day (BDS) group, 46 +/- 7 micromol/l in the pramlintide 60 microg twice per day group, and 29 +/- 8 micromol/l by placebo. The incidence of hypoglycaemia was not different in any pramlintide group compared to the placebo group. Nausea, the most frequent adverse event, subsided after the first week of treatment in the majority of patients. In conclusion, pramlintide improved blood glucose control over a 4-week period without increased hypoglycaemia and was well tolerated. Future studies using a longer period of pramlintide administration with assessment of HbA1c as the measurement of glycaemic control are warranted.

Validation of the heat treatment step used in the production of diaspirin crosslinked hemoglobin (DCLHb) for viral inactivation--effect of crosslinking

Two experiments were performed to assess viral inactivation during the crosslinking and heat treatment steps of the DCLHb manufacturing process. Stroma free hemoglobin (SFHb) collected from a large scale manufacturing lot was tested in a 1:680 scaled down system in which the key parameters used in the manufacturing process were replicated. In the first study Porcine Parvovirus (PPV), a non-enveloped virus, was used to assess inactivation, while in the second study Bovine Viral Diarrhea Virus (BVDV), an enveloped virus, was utilized. In both experiments, the SFHb solution was deoxygenated and an aliquot of virus suspension was added. To initiate the crosslinking reaction, a solution of bis (3,5-dibromosalicyl) fumarate (DBBF) in HEPES buffer was added to the test solution. In both experiments the reaction times and the degree of crosslinking were normal. After crosslinking, the reaction mixtures were heated to 74 +/- 1 degrees C over 30 minutes, held at 74 +/- 1 degrees C for 90 minutes, and cooled to less than 10 degrees C over 30 minutes. In each experiment the degree of crosslinking of final product was 100% and yield of hemoglobin recovery was normal. Samples were removed prior to crosslinking, after crosslinking and before, during and after heat treatment for determination of virus titer and evaluation of key process parameters. The results from these experiments were consistent with those obtained from the full scale manufacturing process for the deoxygenation, crosslinking and the heat treatment step during the production of DCLHb. The results of virus assays showed that crosslinking has no effect on viruses and their subsequent inactivation by heat treatment.

Family-centered care and the anticipated death of a newborn

Providing support for a family whose infant is expected to die requires planning and coordinated intervention by members of the health care team. From diagnosis until the death of the infant, the family's choices and needs must be integrated into an acceptable plan of care. The role of the health care team in this process includes four principal phases: planning for the baby's birth, preparing the siblings, caring for the baby, and supporting the family both at the time of the death and afterward. Specific strategies used by physicians, nurses, and child life specialists can encourage the family's full participation in the birth and death of the infant. A description of one family's experiences highlights implications for family-centered practice.

Predictive assessment of vocal efficiency (PAVE). A method for voice therapy outcome measurement

A prospective study was carried out to examine the degree to which a standard voice assessment could discriminate between the potential benefits of two different voice therapy programmes for individual patients. The study encompassed 200 dysphonia subjects who were referred for voice therapy and had completed treatment within a prescribed two-year period. A standard assessment procedure was carried out on first attendance for each patient and guidelines were used to assign patients to different treatment programmes on the basis of the assessment results. The assessment discriminated well between patients requiring voice therapy to change physiological parameters of voice usage and patients able to self adjust voice usage, and provided an objective means of measuring outcomes.

Mode of action of a lysostaphin-like bacteriolytic agent produced by Streptococcus zooepidemicus 4881

Electron microscopy of zoocin A-treated sensitive streptococcus cells revealed cytoplasmic disruption and ultimately complete rupture of the cell wall. Culture viability and optical density were shown to decrease rapidly and simultaneously in Streptococcus pyogenes FF22 but less quickly in the relatively more resistant Streptococcus mutans 10449. Zoocin A was shown to cleave hexaglycine in a colorimetric cell-free microtiter assay system, and it is concluded that the killing action of zoocin A, like that of lysostaphin, is most probably the result of direct cleavage of the peptidoglycan cross-links in the cell wall. The relationship between sensitivity to zoocin A and the peptidoglycan cross-linkage structure of Streptococcus zooepidemicus, Lactococcus spp., S. pyogenes, Streptococcus gordonii, Streptococcus oralis, S. mutans, and Streptococcus rattus has been evaluated.