Efficacy of intraoperative blood salvage and autotransfusion in living-donor liver transplantation: a retrospective propensity matched case-control study

Background

Liver transplantation (LT) may be associated with massive blood loss and the need for allogeneic blood transfusion. Intraoperative blood salvage autotransfusion (IBSA) can reduce the need for allogeneic blood transfusion. This study aimed to investigate the effectiveness of blood salvage in LT.

Methods

Among 355 adult patients who underwent elective living-donor LT between January 1, 2019, and December 31, 2022, 59 recipients without advanced hepatocellular carcinoma received IBSA using Cell Saver (CS group). Based on sex, age, model for end-stage liver disease (MELD) score, preoperative laboratory results, and other factors, 118 of the 296 recipients who did not undergo IBSA were matched using propensity score (non-CS group). The primary outcome was the amount of intraoperative allogenic red blood cell (RBC) transfusion. Comparisons were made between the two groups regarding the amount of other blood components transfused and postoperative laboratory findings.

Results

The transfused allogeneic RBC for the CS group was significantly lower than that of the non-CS group (1,506.0 ml vs. 1,957.5 ml, P = 0.026). No significant differences in the transfused total fresh frozen plasma (FFP), platelets, cryoprecipitate, and estimated blood loss were observed between the two groups. The postoperative allogeneic RBC transfusion was significantly lower in the CS group than in the non-CS group (1,500.0 ml vs. 2,100.0 ml, P = 0.039). No significant differences in postoperative laboratory findings were observed at postoperative day 1 (POD1) and discharge.

Conclusions

Using IBSA during LT can effectively reduce the need for perioperative allogeneic blood transfusions without causing subsequent coagulopathy.

Toward Burnout Prevention: Can One Short Virtual Reality Relaxation and Mindfulness Training Session for Staff and Patients Decrease Stress and Improve Subjective Sense of Wellbeing?

PURPOSE/OBJECTIVE(S)

Mental wellness of healthcare workers has deteriorated recently, increasing burnout rates. Cancer patients are also often highly distressed, reporting fear, pain, and fatigue. Relaxation and mindfulness training have been shown to decrease stress and anxiety. Currently, the use of virtual reality (VR) for relaxation and mindfulness for cancer patients and oncology clinical staff is an ongoing area of research. We aimed to test the preliminary efficacy of incorporating an innovative digital therapeutic (DTx) we developed at our center in this population.

MATERIALS/METHODS

Cancer patients and clinic staff from one institution's Gastrointestinal and Radiation Oncology departments participated in the immersive VR-enhanced relaxation and mindfulness experience for this IRB-exempt study. Users completed a pre-VR survey via iPad assessing baseline knowledge and practice of stress reduction techniques, baseline stress, and familiarity with VR. In the VR app deployed on an Oculus Quest 2, users chose a relaxing water scene (e.g., stream, beach) and optional soothing background music. Users could also choose a relaxation or mindfulness training audio track. A post-VR survey assessed whether the experience affected their subjective stress and sense of wellbeing ("Yes" or "No") as well as the feasibility of using the app. A binomial test on a single proportion was used to test whether more participants (>50%) indicated their stress was reduced following the VR training than did not. Post-VR qualitative verbal feedback was also collected to identify future changes to the VR app.

RESULTS

Six patients, a patient's son, and forty-three employees used the VR app. Users were aged ≤ 30 years old (18%), 30-50 years (60%), and 50-70 years (22%). Users completed the VR experience in a median of 14 min (IQR: 11-19 min). In the pre-survey, most (78%) reported they felt stress at this point in their lives. In the post-survey, significantly more than the expected proportion of participants (>50%) reported feeling less stressed after using the VR app (88%, n = 44, p <0.001). Most (90%) reported that the VR app improved their subjective sense of wellbeing. All (100%) users reported it was easy to learn the VR controls. Nearly all (96%) reported they would be interested in using this VR app again, including 30% and 38% who reported they would be "extremely likely" and "very likely," respectively, to use the app again.

CONCLUSION

These findings suggest our VR relaxation and mindfulness training was well accepted and could be integrated into the hospital setting in short sessions. Further work should be done based on participant feedback to expand the offerings of this VR app to offer a wider range of relaxation experiences and gamified psychological interventions that can help de-stress, recharge, and build resiliency.

The Impact of Persistent Noise Exposure under Inflammatory Conditions

The aim of this study was to investigate the impact of noise exposure in an intensive care unit (ICU) environment on the development of postoperative delirium in a mouse model that mimics the ICU environment. Additionally, we aimed to identify the underlying mechanisms contributing to delirium and provide evidence for reducing the risk of delirium. In this study, to mimic an ICU environment, lipopolysaccharide (LPS)-injected sepsis mouse models were exposed to a 75 dB noise condition. Furthermore, we assessed neurobehavioral function and observed the level of neuroinflammatory response and blood-brain barrier (BBB) integrity in the hippocampal region. The LPS-injected sepsis mouse model exposed to noise exhibited increased anxiety-like behavior and cognitive impairment. Moreover, severe neuroinflammation and BBB disruption were detected in the hippocampal region. This study provides insights suggesting that persistent noise exposure under systemic inflammatory conditions may cause cognitive dysfunction and anxiety- like behavior via the mediation of BBB disruption and neuroinflammation. As a result, we suggest that the detailed regulation of noise exposure may be required to prevent the development of postoperative delirium.

Family caregivers' responses to a visitation restriction policy at a Korean surgical intensive care unit before and during the coronavirus disease 2019 pandemic

BACKGROUND

Since the COVID-19 pandemic, restricting family visits in the ICU has increased concerns regarding negative psychosocial consequences to patients and families.

OBJECTIVES

To compare the quality of life, depressive symptoms, and emotions in family caregivers of ICU patients before and during the COVID-19 pandemic, and to explore families' perceptions and suggestions for the visitation.

METHODS

A cross-sectional descriptive survey was conducted in 99 family caregivers of adult surgical ICU patients from an urban academic medical center in South Korea (February to July 2021). The WHO's Quality of Life-BREF, Center for Epidemiologic Studies Depression, and Visual Analogue Scale were used to assess quality of life, depressive symptoms, and emotions, respectively. The Family Perception Checklist was used to assess families' perceptions and suggestions about the visitation restriction. Results were compared with the data from our previous survey (n = 187) in 2017.

RESULTS

Family caregivers were mostly women (n = 59), adult children (n = 43) or spouse (n = 38) of patients with mean age of 47.34 years. Family caregivers surveyed during the pandemic reported worsening sadness (54.66 ± 28.93, 45.58 ± 29.44, P = 0.005) and anxiety (53.86 ± 30.07, 43.22 ± 29.02, P = 0.001) than those who were surveyed in. While majority of families were satisfied with the visitation restrictions (86.9%), only 50.5% were satisfied with the amount of information provided on the patient's condition.

CONCLUSIONS

Visitation restriction is necessary during the COVID-19 pandemic despite sadness and anxiety reported in caregivers. Hence, alternative visitation strategies are needed to mitigate psychological distress and provide sufficient information to ICU family caregivers.

1607 Seeing White: Management of TIVA During Autologous Breast Reconstruction

Background

Free flap surgery has inherent risks, and the venous drainage of the Deep Inferior Epigastric Perforator (DIEP) flap is particularly vulnerable to congestion. In these cases, an algorithm for flap salvage should be followed and one of the final steps in this process is a cephalic vein transposition.

Case Report

We describe two patients undergoing mastectomy and immediate bilateral DIEP breast reconstruction, where cephalic vein transposition was required. As part of the Enhanced Recovery After Surgery (ERAS) pathway, patients are anaesthetised with a continuous propofol infusion (Total Intravenous Anaesthesia; TIVA). When the cephalic vein was identified, the propofol infusion was visible within the vein, which would have interrupted TIVA if harvested. To maintain continuous TIVA infusion, the cannula was resited prior to harvest of the cephalic vein. The cephalic vein was anastomosed to the superficial inferior epigastric vein and resolution of the venous congestion was noted.

Conclusions

These cases although rare highlight the importance of robust preoperative planning and communication between the team and preparation for all eventualities to ensure patient safety and successful outcomes. These cases highlight the potential effects vein harvesting or transposition may have on the safe and effective delivery of anaesthetic agents and other medication. We hope these cases prompt a discussion in the preoperative stage for alternate strategies for monitoring and intravenous access in response to diversions from the standard operating procedure.

An unusual cause of acute abdomen and acute renal failure: Djenkolism

The djenkol bean (Archidendron pauciflorum) is a native delicacy in Southeast Asia, though consumption can sometimes lead to djenkolism. Clinical features of djenkolism include acute abdominal pain, hematuria, urinary retention, and acute kidney injury (AKI). The pain can be severe, which often leads to a misdiagnosis of acute abdomen. In this paper, we report the case of an Indonesian migrant with djenkolism. Due to the short history and severity of the abdominal pain, medical professionals suspected acute abdomen and proceeded with a negative exploratory laparotomy. However, djenkolism was suspected once relatives informed the professionals that the patient had consumed djenkol beans hours earlier. The patient recovered through aggressive hydration and urine alkalinization with bicarbonate infusion. We highlight the importance of being aware of this rare cause of AKI, especially in Southeast Asia, in order to provide early diagnoses and prompt treatments.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Prediction of drugs having opposite effects on disease genes in a directed network

Background

Developing novel uses of approved drugs, called drug repositioning, can reduce costs and times in traditional drug development. Network-based approaches have presented promising results in this field. However, even though various types of interactions such as activation or inhibition exist in drug-target interactions and molecular pathways, most of previous network-based studies disregarded this information.

Methods

We developed a novel computational method, Prediction of Drugs having Opposite effects on Disease genes (PDOD), for identifying drugs having opposite effects on altered states of disease genes. PDOD utilized drug-drug target interactions with ‘effect type’, an integrated directed molecular network with ‘effect type’ and ‘effect direction’, and disease genes with regulated states in disease patients. With this information, we proposed a scoring function to discover drugs likely to restore altered states of disease genes using the path from a drug to a disease through the drug-drug target interactions, shortest paths from drug targets to disease genes in molecular pathways, and disease gene-disease associations.

Results

We collected drug-drug target interactions, molecular pathways, and disease genes with their regulated states in the diseases. PDOD is applied to 898 drugs with known drug-drug target interactions and nine diseases. We compared performance of PDOD for predicting known therapeutic drug-disease associations with the previous methods. PDOD outperformed other previous approaches which do not exploit directional information in molecular network. In addition, we provide a simple web service that researchers can submit genes of interest with their altered states and will obtain drugs seeming to have opposite effects on altered states of input genes at http://gto.kaist.ac.kr/pdod/index.php/main.

Conclusions

Our results showed that ‘effect type’ and ‘effect direction’ information in the network based approaches can be utilized to identify drugs having opposite effects on diseases. Our study can offer a novel insight into the field of network-based drug repositioning.

Electronic supplementary material

The online version of this article (doi:10.1186/s12918-015-0243-2) contains supplementary material, which is available to authorized users.

Context-based resolution of semantic conflicts in biological pathways

Background

Interactions between biological entities such as genes, proteins and metabolites, so called pathways, are key features to understand molecular mechanisms of life. As pathway information is being accumulated rapidly through various knowledge resources, there are growing interests in maintaining the integrity of the heterogeneous databases.

Methods

Here, we defined conflict as a status where two contradictory pieces of evidence (i.e. 'A increases B' and 'A decreases B') coexist in a same pathway. This conflict damages unity so that inference of simulation on the integrated pathway network might be unreliable. We defined rule and rule group. A rule consists of interaction of two entities, meta-relation (increase or decrease), and contexts terms about tissue specificity or environmental conditions. The rules, which have the same interaction, are grouped into a rule group. If the rules don't have a unanimous meta-relation, the rule group and the rules are judged as being conflicting.

Results

This analysis revealed that almost 20% of known interactions suffer from conflicting information and conflicting information occurred much more frequently in the literature than the public database.

With consideration for dual functions depending on context, we thought it might resolve conflict to consider context. We grouped rules, which have the same context terms as well as interaction. It's revealed that up to 86% of the conflicts could be resolved by considering context.

Subsequent analysis also showed that those contradictory records generally compete each other closely, but some information might be suspicious when their evidence levels are seriously imbalanced.

Conclusions

By identifying and resolving the conflicts, we expect that pathway databases can be cleaned and used for better secondary analyses such as gene/protein annotation, network dynamics and qualitative/quantitative simulation.

Evaluation of family-centred practices in the early intervention programmes for infants and young children in Singapore with Measure of Processes of Care for Service Providers and Measure of Beliefs about Participation in Family-Centred Service

BACKGROUND

The primary purpose of this study was to report on an evaluation of the perceptions and beliefs of service providers towards family-centred practices in 11 early intervention programmes for infants and young children in Singapore.

METHODS

The Measure of Processes of Care for Service Providers (MPOC-SP) and Measure of Beliefs about Participation in Family-Centred Service (MBP-FCS) were administered to 213 service providers made up of teachers, therapists, psychologists and social workers providing centre-based therapy to children with special needs who were below the age of 6 years.

RESULTS

Exploratory factor analyses were performed with both scales. Nineteen of the 27 MPOC-SP items were retained and supported the original four-factor structure model. The exploratory factor analyses on MBP-FCS provided a less satisfactory outcome. Fourteen of the 28 items were retained and these loaded onto four factors. The two factors relating to Beliefs about benefits of FCS and Beliefs about the absence of negative outcomes from FCS failed to emerge as separate factors. Further multiple regressions indicated that more direct work with families and positive self-efficacy in implementing FCS contributed significantly to explaining service providers' positive perception towards family-centred practice in service delivery.

CONCLUSIONS

This is the first time MPOC-SP and MBP-FCS were administered to a population in an Asian context. While MBP-FCS would benefit from further development work on its construct, MPOC-SP offered important insights into service providers' perspectives about family-centred practices that would have useful implications for professional and service development.

The Singapore liver cancer recurrence (SLICER) score for relapse prediction in patients with resected hepatocellular carcinoma

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Background: Hepatocellular carcinoma (HCC) is a common worldwide cancer associated with extremely poor survival, with surgery the only option for cure in patients with localized disease. Current prognostic models for HCC are algorithms developed on datasets of mainly patients with metastatic or unresectable cancer, and may be less relevant to resectable HCC. Nomograms provide individualized outcome estimates. We constructed a postoperative nomogram, the Singapore liver cancer recurrence (SLICER) score, to predict outcomes of HCC patients who have undergone surgical resection.

Methods: Records for Singaporean patients undergoing first-line curative surgery for localized HCC in one institution between 1992 and 2007 were retrospectively reviewed (n=405). Freedom from relapse (FFR) was the primary outcome measure. An outcome-blinded modeling strategy including clustering, data reduction and transformation, was used. Calibration was tested with bootstrapping (n=200). We compared the performance of this model with other alternative models including CLIP, CUPI, BCLC, and Okuda scores using c-indices and likelihood analysis.

Results: A nomogram (SLICER score) predicting FFR was designed, incorporating vascular invasion, tumor size, multifocality, ECOG status, pre-operative AFP, Childs-Pugh score and cirrhosis. Bootstrap estimates show good calibration at 1, 2, 3, and 5 years postsurgery Comparison of the SLICER score with alternative prognostic models shows superior performance (Table).

Conclusions: The SLICER score enables individualized relapse predictions for patients following curative resection of localized HCC. It permits optimal patient selection for adjuvant therapy trials, biomarker development, and individual counseling.

[Table: see text]

No significant financial relationships to disclose.

Phase I study of SIR-sphere plus sorafenib as first-line treatment in patients with nonresectable hepatocellular carcinoma: The Asia-Pacific Hepatocellular Carcinoma Trials Group protocol 05 (AHCC05)

e15538

Background: Sorafenib has been shown to significantly prolong survival in patients with nonresectable hepatocellular carcinoma (HCC) without however significant tumour regression. The addition of radio-ablative therapy could confer additional survival benefit. This phase I trial was carried out to ascertain the toxicities and safety of this combination and was designed as a prelude to a phase II trial. Methods: Eligible patients were administered SIR-sphere (max dose 3 GBq) and subsequently given Sorafenib therapy (400mg bd) either 14 days (Cohort 1: first 3 patients) or 11 days (Cohort 2: subsequent patients) later. Assessment was carried out for 30 days after commencement of Sorafenib. Results: 10 patients were recruited into this phase I trial. The second patient became ineligible for sorafenib therapy after SIR-sphere due to pulmonary bleeding not related to radio-therapy and was excluded from assessment. The characteristics of the patients are in the Table. At the end of the study period, there was no adverse events (AE) of grade 3 or 4 for Cohort 1 and 3 for Cohort 2. The only serious adverse event (SAE) recorded was from Cohort 2. Conclusions: Starting sorafenib 14 days after SIR-sphere therapy is associated fewer AEs and SAEs. The phase II trial has commenced withsorafenib starting 14 days after SIR-sphere. [Table: see text]

[Table: see text]

Tissue-limited mosaicism in Pallister-Killian syndrome -- a case in point

We report a case of Pallister-Killian syndrome in a term female infant. Antenatal ultrasound showed left diaphragmatic hernia and polyhydramnios. She was ventilated from birth and the diaphragm defect repaired on day 5. She had dysmorphic features, including median cleft palate, patchy frontotemporal alopecia, hypopigmented skin whorls, and bilateral profound sensorineural hearing loss. Fetal and postnatal karyotypes of peripheral lymphocytes were both normal, 46, XX. Subsequently, a skin fibroblast culture showed mosaic tetrasomy of isochromosome 12p both on G-banding and fluorescence in situ hybridization, consistent with Pallister-Killian syndrome. This case illustrates the importance of using the appropriate sample type for karyotype analysis with implications for prenatal and postnatal diagnosis.

Safety of a new conjugate meningococcal C vaccine in infants

BACKGROUND

Group C conjugate meningococcal vaccines (Men C) were introduced into the UK primary immunisation schedule in November 1999. There has been extensive professional and public interest in their efficacy and safety.

AIM

To determine the occurrence of at least one uncommon adverse event in infants related to the administration of the Chiron Men C vaccine.

METHODS

A total of 2796 infants aged approximately 2 months were recruited into the study from areas in and around Sheffield and from Scotland. They were vaccinated with the Chiron Men C vaccine at 2, 3, and 4 months along with routine immunisations. Data on adverse events occurring one month after each dose were collected actively and prospectively and reviewed for possible relation to the vaccine.

RESULTS

There were no deaths. There were no serious adverse events considered definitely or probably caused by the vaccine. Four infants developed serious adverse events (hypotonia, screaming syndrome, maculopapular rash, and agitation, respectively) that were considered possibly related to the vaccine. All recovered completely. Adverse events were seen in 1804 children but were considered possibly related to the vaccine in only 49 (1.8%). On subsequent immunisation there were no recurrences of adverse events considered to be possibly related to the vaccine.

Effect of recombinant human erythropoietin on transfusion needs in preterm infants

OBJECTIVE

To study the efficacy, safety and cost effectiveness of recombinant human erythropoietin (r-HuEPO) in reducing erythrocyte transfusion needs in very low birthweight (VLBW) infants.

METHODS

We conducted a non-blind randomized controlled trial and assigned 100 VLBW infants, less than 33 weeks gestation, to receive either r-HuEPO 750 U/kg per week subcutaneously from day 5 to day 40 or no erythropoietin (EPO). Infants received oral iron 3-6 mg/kg per day from day 10. Transfusion needs were analysed for all enrolled infants and in five weight subgroups: birthweight of less than 600 g, 600-799 g, 800-999 g, 1000-1199 g and infants more than 1200 g.

RESULTS

VLBW infants on r-HuEPO attained higher reticulocyte counts and haematocrit than control infants but the mean number of transfusions and volume of erythrocyte transfused per infant were not statistically different. Of infants 800-999 g at birth, the mean number of transfusions per infant was 2.1 compared with 3.5 transfusions per control infant (P = 0.04). Volume of erythrocytes transfused was 34.9 +/- 32.1 mL/kg in r-HuEPO-treated infants and 56.6 +/- 25.8 mL/kg in control infants (P = 0.03). The cost per patient for transfusion and EPO was S$388 for r-HuEPO recipient and S$438 for control infant. Blood pressure, neutrophil count, platelet count and complications of prematurity were not significantly different in both groups of VLBW infants.

CONCLUSION

r-HuEPO at 750 U/kg per week stimulates erythropoiesis in VLBW infants but significantly reduces the need for erythrocyte transfusion only in infants weighing 800-999 g at birth.

Primary and booster mucosal immune responses to meningococcal group A and C conjugate and polysaccharide vaccines administered to university students in the United Kingdom

Meningococcal group A+C capsular polysaccharide (PS) conjugate vaccines may prime for serum immunoglobulin G (IgG) memory responses to meningococcal capsular PS. It is not known whether these vaccines induce immunological memory at the mucosal level, which may be important in reducing nasopharyngeal carriage. Mucosal immune responses to meningococcal conjugate and PS vaccines in young adults were investigated. Healthy university students were randomized to receive either a groups A+C meningococcal conjugate vaccine (MACconj, n = 100) or a group A+C meningococcal PS vaccine (MACPS, n = 95). One year after the primary immunization, both groups were randomized again to receive a MACconj or a MACPS booster vaccination. Saliva samples were collected before and 1 month after the primary and booster vaccinations. Anti-meningococcal A (MenA) and C (MenC) PS IgA and IgG antibody levels were measured by a standard enzyme-linked immunosorbent assay. After the primary vaccination, salivary MenA and MenC IgG and MenA IgA concentrations were significantly increased after immunization with both MACconj and MACPS vaccines, but the salivary Men C IgA level was increased only after MACPS vaccine (P < 0.01). IgA responses to both serogroups were greater for MACPS than MACconj vaccine (P < 0.05), whereas no significant differences were seen for IgG responses. MenA IgG titers were higher after the MACPS booster in MACconj-primed subjects than after the MACPS primary vaccination, suggesting the presence of IgG memory. Antibody responses to a dose of either MACPS or MACconj were not significantly reduced in those previously given MACPS compared to the primary responses to those vaccines. Meningococcal A+C conjugate and PS vaccines induce significant mucosal responses in young adults. MACconj priming may induce IgG memory at the mucosal level, which is likely to be a reflection of an anamnestic serum IgG response. No evidence of mucosal hyporesponsiveness was observed after MACPS priming in this study.

Primary and booster salivary antibody responses to a 7-valent pneumococcal conjugate vaccine in infants

Salivary anticapsular antibody responses to a 7-valent pneumococcal conjugate vaccine (7VPnC) were measured in healthy infants. Infants received diphtheria-tetanus-pertussis/Haemophilus influenzae type b (DTP/Hib; group 1), DTP/Hib and 7VPnC (group 2), or DTP and 7VPnC/Hib (group 3) at ages 2, 3 and 4 months. All children received 23-valent pneumococcal polysaccharide vaccine at age 13 months. Salivary IgA and IgG responses to primary immunizations were generally poor. IgA mean concentrations at age 5 months were higher in the treatment groups than in control subjects for serotype 14 only (P<.001). At age 13-14 months, there were marked increases in IgA (mean fold difference, 3.7-4.9) and IgG (mean fold difference, 4. 1-11.7) levels for serotypes 4, 9V, 14, and 19F and serotypes 4, 18C, 19F, and 23F, respectively, in the treatment groups. This contrasts with low IgA (1.2 and 1.4) and IgG (1.3 and 2.2) mean fold differences for non-7VPnC serotypes 1 and 5. The results suggest that 7VPnC primes for mucosal memory responses in infants.

Immunogenicity and reactogenicity of a pneumococcal conjugate vaccine administered combined with a haemophilus influenzae type B conjugate vaccine in United Kingdom infants

BACKGROUND

Streptococcus pneumoniae is a major disease burden in young children and the incidence of antibiotic-resistant pneumococcal strains is increasing. Multivalent pneumococcal saccharide-protein conjugate vaccines have recently been developed.

OBJECTIVES

To assess the immunogenicity and reactogenicity of a 7-valent pneumococcal conjugate vaccine (7VPnC) administered as a separate injection or as a combined injection with Haemophilus influenzae type b vaccine (HbOC) at 2, 3 and 4 months of age.

METHODS

Randomized controlled trial of 368 healthy UK infants receiving routine vaccines only (control group), routine vaccines and 7VPnC as a separate injection (separate group), or routine vaccines and 7VPnC combined with HbOC (combined group) at 2, 3 and 4 months. The control group received 7VPnC at 5, 6 and 7 months. All groups received pneumococcal polysaccharide vaccine at 13 to 16 months. Anticapsular IgG antibodies to 7VPnC serotypes were measured at 2, 5, 13 and 14 months and safety data collected.

RESULTS

IgG antibody concentrations at 5 months were higher in the two treatment groups compared with the controls for all 7VPnC serotypes (P < 0.001) and higher in the separate group than the combined group for five 7VPnC serotypes (P < 0.05). For both treatment groups antibody concentrations were higher at 14 months (range, 6.6 to 25.3 microg/ml) than at 5 months (range, 0.6 to 2.5 microg/ml) for all 7VPnC serotypes (P < 0.001).

CONCLUSION

7VPnC was well-tolerated, safe and immunogenic when administered as a separate or as a combined 7VPnC/HbOC injection. Although antibody responses were lower in the infants who received the combination compared with those who received 7VPnC as a separate injection, marked anamnestic responses to polysaccharide challenge were observed, suggesting that both groups were immunologically primed.

Immunogenicity and reactogenicity of a group C meningococcal conjugate vaccine compared with a group A+C meningococcal polysaccharide vaccine in adolescents in a randomised observer-blind controlled trial

This study evaluated the immunogenicity and reactogenicity of a group C meningococcal conjugate vaccine (MenC) compared with a group A+C meningococcal polysaccharide vaccine (MenPS) in healthy adolescents. Subjects were randomised to receive one dose of either MenC (n=92) or MenPS (n=90). Group C meningococcal IgG antibody concentrations and bactericidal titres were higher in the MenC group than the MenPS group at 1 month (22.8 U/ml vs 4.0 U/ml, p<0.001, and 87 vs 20, p<0.001, respectively) and 12 months (6.1 U/ml vs 3.0 U/ml, p<0.001, and 81.3 vs 20.2, p<0.001, respectively). No differences in post immunisation reaction rates were noted between the two vaccinated groups. This study demonstrated the safety and enhanced immunogenicity of the candidate meningococcal conjugate vaccine as compared with the licensed polysaccharide vaccine in adolescents.

Mucosal immune responses to meningococcal group C conjugate and group A and C polysaccharide vaccines in adolescents

Previous studies in children have shown that Haemophilus influenzae type b (Hib) polysaccharide conjugate vaccines can reduce nasopharyngeal carriage of H. influenzae and provide herd immunity and suggest that this effect is mediated through mucosal antibodies. As this phenomenon may operate in other invasive bacterial infections which are propagated by nasopharyngeal carriage, mucosal antibody responses to meningococcal C conjugate and A/C polysaccharide vaccines were investigated. A total of 106 school children aged 11 to 17 years were randomized to receive a single dose of either conjugate or polysaccharide vaccine in an observer-blind study. Before and at 1, 6, and 12 months after immunization, samples of unstimulated saliva were collected and assayed by enzyme-linked immunosorbent assay for group C polysaccharide-specific immunoglobulin A (IgA), IgA1, IgA2 and secretory component, IgG antibodies, and total IgG and IgA. A subset of serum samples were also assayed for specific IgA and IgG antibodies. The concentrations of specific IgA and IgG in saliva were expressed both as nanograms per milliliter and as nanograms per microgram of total IgA or IgG. One month after immunization, significant increases in antibody titers (both IgA and IgG) were observed in saliva in both groups. There were significant subsequent falls in antibody titers by 6 months. Anti-meningococcal C-specific secretory component and IgA antibody titers were closely correlated (r = 0.85, P < 0.001), but there was no significant correlation between salivary and serum IgA titers, suggesting that IgA antibodies are locally produced. Significant correlation was found between salivary and serum IgG titers (r = 0.52, P < 0.01), suggesting that salivary IgG may be serum derived. Compared with polysaccharide vaccine, the conjugate vaccine induced significantly higher salivary IgG responses (P < 0.05), although there were no significant differences between salivary IgA responses to the two vaccines. The conjugate vaccine induced greater salivary IgG responses than a polysaccharide vaccine. Both vaccines induced significant salivary IgA antibodies. Further studies are needed to establish the functional significance of these mucosal responses.

Pediatric combination vaccines

There will be an increasing demand for safe and effective combination vaccines as more paediatric vaccines are developed and licensed for new indications. The successful introduction of new combination vaccines into the childhood immunization schedule has the potential to improve vaccine coverage and thus reduce morbidity and mortality from childhood infections, and also possibly to reduce the cost of vaccines and their delivery. This article reviews the recent literature regarding new combination vaccines and discusses the main issues surrounding the simultaneous administration of multiple vaccine antigens to children.

Development of an in vitro assay system for screening of gp41 inhibitory compounds

The transmembrane protein of HIV-1, gp41, mediates fusion between membranes of the virus and target cell. Strong interaction between the helical regions in the ectodomain of gp41 has been exploited to develop a method that can detect a potential inhibitor against gp41. The N-terminus coiled-coil or the C-terminus helical sequences within the ectodomain of gp41 were inserted into the C-terminus of thioredoxin (Trx) or glutathione S-transferase (GST) to generate the fusion proteins, Trx-N and GST-C, respectively. The inserted sequences of GST-C and Trx-N cause the two proteins to interact with each other and to form a complex. Furthermore, GST-C binds specifically to the surface-coated Trx-N, and the amount of attached GST-C is detected by an ELISA assay using anti-GST antibodies. Peptides derived from the helical regions of gp41 compete with GST-C for binding to Trx-N as well as prevent the gp41-mediated cell fusion. This in vitro assay system can be applied to screening compounds that have an inhibitory activity against gp41.

Chronic lung disease in very low birthweight infants: a 5-year review

OBJECTIVES

To determine the incidence, clinical spectrum and outcome of very low birthweight (VLBW) infants with chronic lung disease (CLD), and evaluate associated factors.

METHODOLOGY

Retrospective review of 265 VLBW infants managed in the NICU from January 1988 to December 1992.

RESULTS

The overall neonatal survival rate for VLBW infants was 83%. Sixty-five (25%) infants had CLD, of whom 42% had severe CLD. Mortality in infants with CLD was 11%. In contrast with infants without CLD, CLD infants had significantly higher risk of adverse neurodevelopment with cerebral palsy documented in 13.5% and functional disability recorded in 34.6% at 2 years corrected age. Factors associated with the development of CLD included; decreasing birthweight (OR 0.98, CI 0.97-0.99), septicaemia (OR 4.96, CI 1.57-15.65), necrotizing enterocolitis (OR 119.07, CI 4.98-2845.04), hyaline membrane disease (OR 5.34, CI 1.83-15.55), patent ductus arteriosus (OR 4.46, CI 1.75-11.36) and increasing fraction of inspired oxygen concentration in the first week of life (OR 1.09, CI 1.04-1.14).

CONCLUSIONS

Chronic lung disease occurs frequently in VLBW infants and is associated with a high incidence of adverse neurodevelopment. Further studies to clarify the role of non-respiratory factors such as patent ductus arteriosus (PDA) and sepsis in the pathogenesis of CLD may reduce the incidence or prevent the development of CLD in these preterm infants.