A review of -multidrug-resistant Enterobacteriaceae in a neonatal unit in Johannesburg, South Africa

Background

Multi-drug resistant organisms are an increasingly important cause of neonatal sepsis.

Aim

This study aimed to review neonatal sepsis caused by multi-drug resistant Enterobacteriaceae (MDRE) in neonates in Johannesburg, South Africa.

Methods

This was a cross sectional retrospective review of MDRE in neonates admitted to a tertiary neonatal unit between 1 January 2013 and 31 December 2015.

Results

There were 465 infections in 291 neonates. 68.6% were very low birth weight (< 1500 g). The median age of infection was 14.0 days. Risk factors for MDRE included prematurity (p = 0.01), lower birth weight (p = 0.04), maternal HIV infection (p = 0.02) and oxygen on day 28 (p < 0.001). The most common isolate was Klebsiella pneumoniae (66.2%). Total MDRE isolates increased from 0.39 per 1000 neonatal admissions in 2013 to 1.4 per 1000 neonatal admissions in 2015 (p < 0.001). There was an increase in carbapenem-resistant Enterobacteriaceae (CRE) from 2.6% in 2013 to 8.9% in 2015 (p = 0.06). Most of the CRE were New Delhi metallo—β lactamase- (NDM) producers.

The all-cause mortality rate was 33.3%. Birth weight (p = 0.003), necrotising enterocolitis (p < 0.001) and mechanical ventilation (p = 0.007) were significantly associated with mortality. Serratia marcescens was isolated in 55.2% of neonates that died.

Conclusions

There was a significant increase in MDRE in neonatal sepsis during the study period, with the emergence of CRE. This confirms the urgent need to intensify antimicrobial stewardship efforts and address infection control and prevention in neonatal units in LMICs. Overuse of broad- spectrum antibiotics should be prevented.

A review of delivery room resuscitation in very low birth weight infants in a middle income country

BACKGROUND

Advanced levels of delivery room resuscitation in very low birth weight infants are reported to be associated with death and complications of prematurity. In resource limited settings, the need for delivery room resuscitation is often used as a reason to limit care in these infants.

METHODS

This was a review of delivery room resuscitation in very low birth weight infants born in a tertiary hospital in South Africa between 01 January 2013 and 30 June 2016. Outcomes included death and serious complications of prematurity. Advanced delivery room resuscitation was defined as the need for intubation, chest compressions or the administration of adrenaline.

RESULTS

A total of 1511 very low birth weight infants were included in the study. The majority (1332/1511 (88.2%) required oxygen in the delivery room. Face mask ventilation was needed in 45.2% (683/1511). Advanced delivery room resuscitation was only required in 10.6% (160/1511). More than half the infants who required advanced delivery room resuscitation died (89/160; 55.6%). Advanced delivery room resuscitation was required in significantly more infants <1000 grams at birth than those infants >1000 grams (83/539 (15.4%) vs 77/972 (7.9%) p < 0.001). Advanced delivery room resuscitation was significantly associated with a 5 minute Apgar score < 6 (OR 13.8 (95%CI 8.6-22.0), supplemental oxygen at day 28 (OR 2.2 (95% CI 1.4-3.9), metabolic acidosis (OR 2.3 (95% CI 1.1-4.8) and death (OR 1.9 95% CI 1.1-3.3). Other serious complications of prematurity were not associated with advanced delivery room resuscitation. Mortality was increased in infants with a low admission temperature (35.1 °C (SD 0.92) vs 36.1 °C (SD 1.4) (p < 0.001).

CONCLUSION

There was a high mortality rate associated with advanced delivery room resuscitation; however complications of prematurity were not increased in survivors..The need for advanced delivery room resuscitation alone should not be used as a predictor of poor outcome in very low birth weight infants. Survivors of advanced delivery room resuscitation should be afforded ventilatory support if required. Special care must be taken to avoid hypothermia in very low birth weight infants requiring resuscitation at birth.

Long-term efficacy and safety results of taliglucerase alfa up to 36 months in adult treatment-naïve patients with Gaucher disease

Taliglucerase alfa is an intravenous enzyme replacement therapy approved for treatment of type 1 Gaucher disease (GD), and is the first available plant cell–expressed recombinant therapeutic protein. Herein, we report long‐term safety and efficacy results of taliglucerase alfa in treatment‐naïve adult patients with GD. Patients were randomized to receive taliglucerase alfa 30 or 60 U/kg every other week, and 23 patients completed 36 months of treatment. Taliglucerase alfa (30 U/kg; 60 U/kg, respectively) resulted in mean decreases in spleen volume (50.1%; 64.6%) and liver volume (25.6%; 24.4%) with mean increases in hemoglobin concentration (16.0%; 35.8%) and platelet count (45.7%; 114.0%), and mean decreases in chitotriosidase activity (71.5%; 82.2%). All treatment‐related adverse events were mild to moderate in intensity and transient. The most common adverse events were nasopharyngitis, arthralgia, upper respiratory tract infection, headache, pain in extremity, and hypertension. These 36‐month results of taliglucerase alfa in treatment‐naïve adult patients with GD demonstrate continued improvement in disease parameters with no new safety concerns. These findings extend the taliglucerase alfa clinical safety and efficacy dataset. www.clinicaltrials.gov identifier NCT00705939. Am. J. Hematol. 91:656–660, 2016. © 2016 Wiley Periodicals, Inc.

Retrospective cross-sectional review of survival rates in critically ill children admitted to a combined paediatric/neonatal intensive care unit in Johannesburg, South Africa, 2013-2015

OBJECTIVE

Report on survival to discharge of children in a combined paediatric/neonatal intensive care unit (PNICU).

DESIGN AND SETTING

Retrospective cross-sectional record review.

PARTICIPANTS

All children (medical and surgical patients) admitted to PNICU between 1 January 2013 and 30 June 2015.

OUTCOME MEASURES

Primary outcome-survival to discharge. Secondary outcomes-disease profiles and predictors of mortality in different age categories.

RESULTS

There were 1454 admissions, 182 missing records, leaving 1272 admissions for review. Overall mortality rate was 25.7% (327/1272). Mortality rate was 41.4% (121/292) (95% CI 35.8% to 47.1%) for very low birthweight (VLBW) babies, 26.6% (120/451) (95% CI 22.5% to 30.5%) for bigger babies and 16.2% (86/529) (95% CI 13.1% to 19.3%) for paediatric patients. Risk factors for a reduced chance of survival to discharge in paediatric patients included postcardiac arrest (OR 0.21, 95% CI 0.09 to 0.49), inotropic support (OR 0.085, 95% CI 0.04 to 0.17), hypernatraemia (OR 0.16, 95% CI 0.04 to 0.6), bacterial sepsis (OR 0.32, 95% CI 0.16 to 0.65) and lower respiratory tract infection (OR 0.54, 95% CI 0.30 to 0.97). Major birth defects (OR 0.44, 95% CI 0.26 to 0.74), persistent pulmonary hypertension of the new born (OR 0.44, 95% CI 0.21 to 0.91), metabolic acidosis (OR 0.23, 95% CI 0.12 to 0.74), inotropic support (OR 0.23, 95% CI 0.12 to 0.45) and congenital heart defects (OR 0.29, 95% CI 0.13 to 0.62) predicted decreased survival in bigger babies. Birth weight (OR 0.997, 95% CI 0.995 to 0.999), birth outside the hospital (OR 0.21, 95% CI 0.05 to 0.84), HIV exposure (OR 0.54, 95% CI 0.30 to 0.99), resuscitation at birth (OR 0.49, 95% CI 0.25 to 0.94), metabolic acidosis (OR 0.25, 95% CI 0.10 to 0.60) and necrotising enterocolitis (OR 0.23, 95% CI 0.12 to 0.46) predicted poor survival in VLBW babies.

CONCLUSIONS

Ongoing mortality review is essential to improve provision of paediatric critical care.

Comparison of morbidity and mortality of very low birth weight infants in a Central Hospital in Johannesburg between 2006/2007 and 2013

Background

Health protocols need to be guided by current data on survival and benefits of interventions within the local context. Periodic clinical audits are required to inform and update health care protocols. This study aimed to review morbidity and mortality in very low birth weight (VLBW) infants in 2013 compared with similar data from 2006/2007.

Methods

We performed a retrospective review of patients’ records from a neonatal computer database for 562 VLBW infants. These neonates weighed between 500 and 1500 g at birth, and were admitted within 48 hours after birth between 01 January 2013 and 31 December 2013. Patients’ characteristics, complications of prematurity, and therapeutic interventions were compared with 2006/2007 data. Univariate analysis and multiple logistic regression were performed to establish significant associations of various factors with survival to discharge for 2013.

Results

Survival in 2013 was similar to that in 2006/2007 (73.4% vs 70.2%, p = 0.27). However, survival in neonates who weighed 750–900 g significantly improved from 20.4% in 2006/2007 to 52.4% in 2013 (p = 0.001). The use of nasal continuous positive airway pressure (NCPAP) increased from 20.3% to 62.9% and surfactant use increased from 19.2% to 65.5% between the two time periods (both p < 0.001). Antenatal care attendance improved from 54.4% to 70.6% (p = 0.001) and late onset sepsis (>72 hours after birth) increased from 12.5% to 19% (p = 0.006) between the two time periods. Other variables remained unchanged between 2006/2007 and 2013. The main determinants of survival to discharge in 2013 were birth weight (odds ratio 1.005, 95% confidence interval 1.003–1.0007, resuscitation at birth (2.673, 1.375–5.197), NCPAP (0.247, 0.109–0.560), necrotising enterocolitis (4.555, 1.659–12.51), and mode of delivery, including normal vaginal delivery (0.456, 0.231–0.903) and vaginal breech (0.069, 0.013–0.364).

Conclusions

There was a marked improvement in the survival of neonates weighing between 750 and 900 g at birth, most likely due to provision of surfactant and NCPAP. Provision of NCPAP, prevention of necrotising enterocolitis, and control of infection need to be prioritised in VLBW infants to improve their outcome.

Nanoscale roughness micromilled silica evanescent refractometer

We demonstrate machining of precision slots in silica with nanoscale roughness for applications in photonics. Using our in-house developed milling system we have achieved machined slots with surface roughness of 3.0 nm (Sa) and 17 µm depth of cut. This result represents eight times improvement in surface roughness and forty times increase in depth of cut than previously reported. We also demonstrate integration of these milled slots with UV-written waveguides and Bragg gratings to create optical refractometers, based on monitoring Fabry-Pérot spectral fringe changes.

Integrated optical dual-cantilever arrays in silica on silicon

A dual cantilever device has been demonstrated which can operate as a force sensor or variable attenuator. The device is fabricated using physical micromachining techniques that do not require cleanroom class facilities. The response of the device to mechanical actuation is measured, and shown to be well described by conventional fiber optic angular misalignment theory. The device has the potential to be utilized within integrated optical components for sensors or attenuators. An array of devices was fabricated with potential for parallel operation.

Background changing patterns of neonatal fungal sepsis in a developing country

BACKGROUND

Candida albicans is the predominant isolate in many neonatal fungal bloodstream infections (BSIs), so fluconazole is used as empiric antifungal therapy.

AIM

To determine the predominant organisms, antifungal sensitivity patterns, clinical and demographic risk factors and crude mortality rate in neonatal fungal BSI cases.

SUBJECTS AND METHODS

This is a review of all neonatal fungal BSI cases between January 2007 and December 2011.

RESULTS

Fifty-nine patients were included in the study. Candida parapsilosis (54.2%) was isolated in majority of the cases, followed by C. albicans (27.1%). Fluconazole resistance was present in 16 of 32 cases of C. parapsilosis versus 1 of 16 cases of C. albicans (P = 0.003). Mortality rate was 45.8%. Surgical problems were present in 55.9%. Death was significantly associated with lower birth weight (P = 0.046) and necrotizing enterocolitis (P = 0.034).

CONCLUSIONS

The increase in neonatal fungal BSI and resistant organisms highlights the need to review use of routine empiric fluconazole and to implement preventive measures.

Bacterial bloodstream infections in neonates in a developing country

Background. Ongoing surveillance of antimicrobial sensitivity patterns of bacteria isolated in bloodstream infections guides empiric antibiotic therapy in neonatal sepsis. Methods. Sensitivity profiles of neonatal bacterial bloodstream infections in a tertiary hospital were reviewed between 01/06/2009 and 30/06/2010 . Results. There were 246 episodes of bloodstream infection in 181 individuals—(14.06 episodes in10.35 patients/1000 patient days or 14.4 episodes in 10.6 babies/1000 live births. The majority were (93.5%) were late onset and most (54.9%) were gram positive. There were 2.28 sepsis-related deaths /1000 patient days or 2.3/1000 live births. Death was significantly associated with gram-negative infections (P < 0.001), multiple gestation (P < 0.001), shock (P = 0.008), NEC (P = 0.002), and shorter duration of hospital stay (P < 0.001). Coagulase-negative staphylococcus was isolated in 19.1%, K. pneumoniae ESBL in 12.1%, and A. baumanni in 10.9%. S. agalactiae predominated in early onset sepsis. Methicillin resistance was present in 86% of CoNS and 69.5% of S. aureus; 46% enterococcal isolates were ampicillin resistant. The majority (65%) of K. pneumoniae isolates were ESBL producers. Ampicillin resistance was present in 96% of E. coli. Conclusions. Penicillin and an aminoglycoside would be suitable empiric therapy for early onset sepsis and meropenem with gentamycin or ceftazidime with amikacin for late onset sepsis.

Developmental outcome of very low birth weight infants in a developing country

Background

Advances in neonatal care allow survival of extremely premature infants, who are at risk of handicap. Neurodevelopmental follow up of these infants is an essential part of ongoing evaluation of neonatal care. The neonatal care in resource limited developing countries is very different to that in first world settings. Follow up data from developing countries is essential; it is not appropriate to extrapolate data from units in developed countries. This study provides follow up data on a population of very low birth weight (VLBW) infants in Johannesburg, South Africa.

Methods

The study sample included all VLBW infants born between 01/06/2006 and 28/02/2007 and discharged from the neonatal unit at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). Bayley Scales of Infant and Toddler Development Version 111 (BSID) 111 were done to assess development. Regression analysis was done to determine factors associated with poor outcome.

Results

178 infants were discharged, 26 were not available for follow up, 9 of the remaining 152 (5.9%) died before an assessment was done; 106 of the remaining 143 (74.1%) had a BSID 111 assessment. These 106 patients form the study sample; mean birth weight and mean gestational age was 1182 grams (SD: 197.78) and 30.81 weeks (SD: 2.67) respectively. The BSID (111) was done at a median age of 16.48 months. The mean cognitive subscale was 88.6 (95% CI: 85.69 - 91.59), 9 (8.5%) were < 70, mean language subscale was 87.71 (95% CI: 84.85 - 90.56), 10 (9.4%) < 70, and mean motor subscale was 90.05 (95% CI: 87.0 - 93.11), 8 (7.6%) < 70. Approximately one third of infants were identified as being at risk (score between 70 and 85) on each subscale. Cerebral palsy was diagnosed in 4 (3.7%) of babies. Factors associated with poor outcome included cystic periventricular leukomalacia (PVL), resuscitation at birth, maternal parity, prolonged hospitalisation and duration of supplemental oxygen. PVL was associated with poor outcome on all three subscales. Birth weight and gestational age were not predictive of neurodevelopmental outcome.

Conclusion

Although the neurodevelopmental outcome of this group of VLBW infants was within the normal range, with a low incidence of cerebral palsy, these results may reflect the low survival of babies with a birth weight below 900 grams. In addition, mean subscale scores were low and one third of the babies were identified as "at risk", indicating that this group of babies warrants long-term follow up into school going age.

Adenovirus-mediated hypoxia-targeted gene therapy using HSV thymidine kinase and bacterial nitroreductase prodrug-activating genes in vitro and in vivo

Hypoxia is an important factor in tumor growth. It is associated with resistance to conventional anticancer treatments. Gene therapy targeting hypoxic tumor cells therefore has the potential to enhance the efficacy of treatment of solid tumors. Transfection of a panel of tumor cell lines with plasmid constructs containing hypoxia-responsive promoter elements from the genes, vascular endothelial growth factor (VEGF) and erythropoietin, linked to the minimal cytomegalovirus (mCMV) or minimal interleukin-2 (mIL-2) promoters showed optimum hypoxia-inducible luciferase reporter gene expression with five repeats of VEGF hypoxic-response element linked to the mCMV promoter. Adenoviral vectors using this hypoxia-inducible promoter to drive therapeutic transgenes produced hypoxia-specific cell kill of HT1080 and HCT116 cells in the presence of prodrug with both herpes simplex virus thymidine kinase/ganciclovir and nitroreductase (NTR)/CB1954 prodrug-activating systems. Significant cytotoxic effects were also observed in patient-derived human ovarian cancer cells. The NTR/CB1954 system provided more readily controllable transgene expression and so was used for in vivo experiments of human HCT116 xenografts in nude mice. Subjects treated intratumorally with Ad-VEGFmCMV-NTR and intraperitoneal injection of CB1954 demonstrated a statistically significant reduction in tumor growth. Immunohistochemistry of treated xenografts showed a good correlation between transgene expression and hypoxic areas. Further investigation of these hypoxia-inducible adenoviral vectors, alone or in combination with existing modalities of cancer therapy, may aid in the future development of successful Gene-Directed Enzyme Prodrug Therapy systems, which are much needed for targeting solid tumors.

Small molecule FGF receptor inhibitors block FGFR-dependent urothelial carcinoma growth in vitro and in vivo

BACKGROUND

Activating mutations of FGFR3 are frequently identified in superficial urothelial carcinoma (UC) and increased expression of FGFR1 and FGFR3 are common in both superficial and invasive UC.

METHODS

The effects of inhibition of receptor activity by three small molecule inhibitors (PD173074, TKI-258 and SU5402) were investigated in a panel of bladder tumour cell lines with known FGFR expression levels and FGFR3 mutation status.

RESULTS

All inhibitors prevented activation of FGFR3, and inhibited downstream MAPK pathway signalling. Response was related to FGFR3 and/or FGFR1 expression levels. Cell lines with the highest levels of FGFR expression showed the greatest response and little or no effect was measured in normal human urothelial cells or in UC cell lines with activating RAS gene mutations. In sensitive cell lines, the drugs induced cell cycle arrest and/or apoptosis. IC(50) values for PD173074 and TKI-258 were in the nanomolar concentration range compared with micromolar concentrations for SU5402. PD173074 showed the greatest effects in vitro and in vivo significantly delayed the growth of subcutaneous bladder tumour xenografts.

CONCLUSION

These results indicate that inhibition of FGFR1 and wild-type or mutant FGFR3 may represent a useful therapeutic approach in patients with both non-muscle invasive and muscle invasive UC.

Determinants of survival in very low birth weight neonates in a public sector hospital in Johannesburg

BACKGROUND

Audit of disease and mortality patterns provides essential information for health budgeting and planning, as well as a benchmark for comparison. Neonatal mortality accounts for about 1/3 of deaths < 5 years of age and very low birth weight (VLBW) mortality for approximately 1/3 of neonatal mortality. Intervention programs must be based on reliable statistics applicable to the local setting; First World data cannot be used in a Third World setting. Many neonatal units participate in the Vermont Oxford Network (VON); limited resources prevent a significant number of large neonatal units from developing countries taking part, hence data from such units is lacking. The purpose of this study was to provide reliable, recent statistics relevant to a developing African country, useful for guiding neonatal interventions in that setting.

METHODS

This was a retrospective chart review of 474 VLBW infants admitted within 24 hours of birth, between 1 July 2006 and 30 June 2007, to the neonatal unit of Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) in Johannesburg, South Africa. Binary outcome logistic regression on individual variables and multiple logistic regression was done to identify those factors determining survival.

RESULTS

Overall survival was 70.5%. Survival of infants below 1001 grams birth weight was 34.9% compared to 85.8% for those between 1001 and 1500 grams at birth. The main determinant of survival was birth weight with an adjusted survival odds ratio of 23.44 (95% CI: 11.22 - 49.00) for babies weighing between 1001 and 1500 grams compared to those weighing below 1001 grams. Other predictors of survival were gender (OR 3. 21; 95% CI 1.6 - 6.3), birth before arrival at the hospital (BBA) (OR 0.23; 95% CI: 0.08 - 0.69), necrotising enterocolitis (NEC) (OR 0.06; 95% CI: 0.02 - 0.20), hypotension (OR 0.05; 95% CI 0.01 - 0.21) and nasal continuous positive airways pressure (NCPAP) (OR 4.58; 95% CI 1.58 - 13.31).

CONCLUSIONS

Survival rates compare favourably with other developing countries, but can be improved; especially in infants < 1001 grams birth weight. Resources need to be allocated to preventing the birth of VLBW babies outside hospital, early neonatal resuscitation, provision of NCPAP and prevention of NEC.

Feeding of infants of HIV-positive mothers

PURPOSE OF REVIEW

To highlight recent research that has contributed to an improved understanding of, or resulted in, important changes in the approach to feeding HIV-exposed infants.

RECENT FINDINGS

The administration of antiretroviral therapy to a HIV-positive pregnant woman and its continued use during breast-feeding significantly reduce postnatal HIV transmission to her child. Similarly, extended antiretroviral prophylaxis to the breast-feeding infant dramatically decreases HIV transmission and promotes HIV-free child survival. Predominant breast-feeding may be as effective as exclusive breast-feeding in reducing HIV transmission risk. The protective role of immune modulators such as interferon-gamma and interleukin-15 in preventing breast milk transmission is being better appreciated. Although infant-feeding counseling is critical to the success of infant survival strategies, it is generally done poorly with few examples of successful consequences other than in research settings.

SUMMARY

Breast-feeding of HIV-exposed infants can be made considerably safer in resource-constrained settings through the provision of maternal highly active antiretroviral therapy (HAART), maternal short-course antiretrovirals, and extended infant antiretroviral prophylaxis.

Factors affecting sodium hypochlorite extraction of CCA from treated wood

Significant amounts of chromated copper arsenate (CCA) treated wood products, such as utility poles and residential construction wood, remain in service. There is increasing public concern about environmental contamination from CCA-treated wood when it is removed from service for reuse or recycling, placed in landfills or burned in commercial incinerators. In this paper, we investigated the effects of time, temperature and sodium hypochlorite concentration on chromium oxidation and extraction of chromated copper arsenate from CCA-treated wood (Type C) removed from service. Of the conditions evaluated, reaction of milled wood with sodium hypochlorite for one hour at room temperature followed by heating at 75 degrees C for two hours gave the highest extraction efficiency. An average of 95% Cr, 99% Cu and 96% As could be removed from CCA-treated, milled wood by this process. Most of the extracted chromium was oxidized to the hexavalent state and could therefore be recycled in a CCA treating solution. Sodium hypochlorite extracting solutions could be reused several times to extract CCA components from additional treated wood samples.

Earlier discharge of very low birthweight infants from an under-resourced African hospital: a randomised trial

BACKGROUND

Very low birthweight (VLBW) infants contribute substantially to the workload and expenditure of any neonatal unit. Earlier discharge might offer advantages to the infant, the family and the health service.

AIM

To establish the outcome of preterm, VLBW infants discharged at a weight of > or = 1650 g compared with the unit's practise of discharging at a weight of > or = 1800 g.

METHODS

A total of 120 infants (62 early discharges, 58 routine discharges) were followed up for 3 months after discharge from Chris Hani Baragwanath Hospital in Soweto, South Africa. The early-discharge group was discharged at > or = 1650 g and the routine-discharge group at > or = 1800 g. Growth, morbidity and mortality at 1 and 3 months after discharge were compared.

RESULTS

At 3 months, the rate of weight gain (mean 30 vs 33 g/kg/day, p=0.06) and head circumference growth (38.9 vs 39.5 cm, p=0.10) were similar in both groups. There were no differences between the early- and routine-discharge groups in the number of outpatient visits (24 vs 16, p=0.18), frequency of re-admission (9 vs 4, p=0.17) or mortality [1 (1.6%) vs 3 (5.2%), p=0.27] following discharge.

CONCLUSION

If home circumstances are adequate, it is as safe to discharge well, singleton VLBW infants from hospital at a weight of > or = 1650 g as at > or = 1800 g.

Reducing the cost of screening novel agents using the hollow fibre assay

Although the in vivo hollow fibre assay (HFA) as utilised by the National Cancer Institute is a highly effective screening tool, it has not been adopted en masse in the cancer pharmacology field. However, in laboratories which have adopted it, the effectiveness of HFA has also been confirmed. If immunocompetent mice could be used with the HFA, thereby reducing the cost of the assay, accessibility would increase and reductions in the cost of selecting appropriate agents for early clinical trials would result. It was demonstrated here that there was no difference in terms of cell growth and response to chemotherapy for cancer cells in hollow fibres in immunocompetent compared with immunodeficient mice. The HFA can thus be performed in these less expensive and more easily available mice with the implication of considerable savings to the preclinical cancer pharmacology community.

Effect of carbon dioxide injection on production of wood cement composites from waste medium density fiberboard (MDF)

The possibility of recycling waste medium density fiberboard (MDF) into wood-cement composites was evaluated. Both new fibers and recycled steam exploded MDF fibers had poor compatibility with cement if no treatment was applied, due to interference of the hydration process by the water soluble components of the fiber. However, this issue was resolved when a rapid hardening process with carbon dioxide injection was adopted. It appears that the rapid carbonation allowed the board to develop considerable strength before the adverse effects of the wood extractives could take effect. After 3-5 min of carbon dioxide injection, the composites reached 22-27% of total carbonation and developed 50-70% of their final (28-day) strength. Composites containing recycled MDF fibers had slightly lower splitting tensile strength and lower tensile toughness properties than those containing new fibers especially at a high fiber/cement ratio. Composites containing recycled MDF fibers also showed lower values of water absorption. Unlike composites cured conventionally, composites cured under CO(2) injection developed higher strength and toughness with increased fiber content. Incorporation of recycled MDF fibers into wood cement composites with CO(2) injection during the production stage presents a viable option for recycling of this difficult to manage waste material.

Polymerase chain reaction for diagnosis of human immunodeficiency virus infection in infancy in low resource settings

BACKGROUND

Diagnosis of human immunodeficiency virus (HIV) is essential for accessing treatment. Current HIV diagnostic protocols for infants require adaptation and validation before they can be implemented in the developing world. The timing and type of HIV assays will be dictated by country-specific circumstances and experience from similar settings. The performance of an HIV-1 DNA polymerase chain reaction (PCR) test, and in particular a single test at 6 weeks of age, in diagnosing HIV subtype C infection acquired in utero or peripartum was assessed.

METHODS

A retrospective review of 1825 Amplicor HIV-1 DNA PCR version 1.5 tests performed between 2000 and 2004 in 2 laboratories in Johannesburg, South Africa on 769 effectively non-breast-fed infants from 3 clinically well characterized cohorts was undertaken. The HIV status of each infant was used as the standard against which the HIV PCR results were compared.

RESULTS

The overall sensitivity and specificity of the HIV PCR test were 99.3 and 99.5% respectively. A single test was 98.8% sensitive and 99.4% specific in the 627 infants tested at 6 weeks of age (58 HIV-infected and 569 HIV-uninfected). Repeat testing of all positive HIV PCR tests minimized false positive results.

CONCLUSIONS

In resource-poor settings where HIV PCR testing in an environment of good laboratory practice is feasible, a single 6-week HIV DNA PCR test can increase identification of HIV-infected children substantially from current levels. Further operational research on how best to implement and monitor such a diagnostic protocol in specific local settings, especially in breast-fed infants, is necessary.

Survival of very-low-birth-weight infants according to birth weight and gestational age in a public hospital

OBJECTIVES

To determine the survival rates for infants weighing 500 - 1 499 g according to birth weight (BW) and gestational age (GA).

DESIGN

This was a retrospective cohort study. Pregnancy and delivery data were collected soon after birth and neonatal data at discharge or at death.

SETTING

Chris Hani Baragwanath Hospital (CHBH), a public-sector referral hospital, affiliated to the University of the Witwatersrand.

SUBJECTS

Live births weighing between 500 g and 1 499 g delivered at or admitted to CHBH from January 2000 to December 2002.

OUTCOME MEASURES

BW and GA-specific survival rates for all live infants born at CHBH and for those admitted for neonatal care.

RESULTS

Seventy-two per cent of infants survived until discharge. The survival to discharge rate was 32% for infants weighing < 1 000 g, and 84% for those weighing 1 000 - 1 499 g. Survival rates at 26, 27 and 28 weeks' gestation were 38%, 50% and 65% respectively. Survival rates for infants admitted to the neonatal unit were better than rates for all live births, especially among those weighing < 1 000 g or with a GA < 28 weeks. There was a marked increase in survival between the 900 - 999 g and 1 000 - 1 099 g weight groups. Provision of antenatal care, caesarean section, female gender and an Apgar score more than 5 at 1 or 5 minutes were associated with better survival to hospital discharge.

CONCLUSION

Survival among infants weighing less than 1 000 g is poor. In addition to severe prematurity, the poor survival among these infants (< 1 000 g) is most likely related to the fact that they were not offered mechanical ventilation. Mechanical ventilation should be offered to infants weighing < 1 000 g as it may improve their survival even in institutions with limited resources.

Development of a modified hollow fibre assay for studying agents targeting the tumour neovasculature

BACKGROUND

Previous studies have shown extensive vascularisation surrounding subcutaneously implanted fibres when the duration of the US National Cancer Institute (NCI) hollow fibre assay was prolonged.

MATERIALS AND METHODS

The feasibility of adapting the NCI assay for evaluating agents targeting the tumour vasculature was investigated in vitro and in vivo. Finally, in the optimised assay, changes in neovasculature formation around the fibres following treatment with the anti-vascular agent paclitaxel were quantified by immunohistochemistry.

RESULTS

Correlations between cell number seeded, time in culture and vascular endothelial growth factor (VEGF) secretion were seen. In vivo studies showed that transplanting single rather than 3 fibres at a site reduced inflammation, reducing the length of the fibre transplanted, as did without any significant loss in cell growth over 21 days. A statistically significant reduction in neovascularisation surrounding the fibres was seen accompanying paclitaxel treatment.

CONCLUSION

Modifications made here to the NCI hollow fibre assay demonstrate its potential for analysing anti-tumour vasculature agents.

Evaluation of transgenic approaches for controlling tuber moth in potatoes

A wide spectrum of strategies to genetically engineer potato plants resistant to potato tuber moth, Phthorimaea operculella (Zeller), have been investigated. The potato cv Iwa was transformed with a range of genes under the transcriptional control of the CaMV 35S promoter using Agrobacterium-mediated gene transfer. The transferred genes encode protease inhibitors (spleen inhibitor and alpha1-antitrypsin inhibitor), biotin-binding proteins (avidin and streptavidin) and Cry proteins (crylAc9, cry1Ba1, crylCa5 and cry9Aa2). Of these three transgenic approaches, cry genes have proved the most useful. In order to control the expression of the cry genes in foliage and not in the tubers a light-inducible Lhca3 promoter from potato was also used. The interaction of different cry genes was investigated using an experimental approach to simulate gene pyramiding in potato. Potato plants transgenic for both the crylAc9 and cryAa2 genes were developed and evaluated to help provide a more durable resistance to potato tuber moth.

Serum procalcitonin as an early marker of neonatal sepsis

BACKGROUND

It has recently been suggested that procalcitonin (PCT) is of value in the diagnosis of neonatal sepsis, with varying results. This study was to evaluate the role of PCT as a single early marker of neonatal sepsis.

SETTING

Neonatal Unit, Johannesburg Hospital, and Microbiology Laboratory, National Health Laboratory Service (NHLS), South Africa.

SUBJECTS AND METHODS

Neonates undergoing evaluation for sepsis between April and August 2002 were eligible for inclusion. Patients were categorised into 'no infection', 'possible infection' and 'definite infection' on the basis of C-reactive protein (CRP), white cell count (WCC), platelet count and blood culture results. PCT was correlated with infection categories.

RESULTS

One hundred and eighty-three neonates were enrolled. One hundred and eighteen had no infection, 52 possible infection and 13 definite infection. PCT differed significantly among infection categories (p < 0.0001) and correlated significantly with CRP at presentation (correlation coefficient 0.404, p < 0.001) and CRP at 24 hours (correlation coefficient 0.343, p < 0.001). PCT predicted 89.5% of definite infection. Receiver operating characteristic (ROC) analysis for PCT to predict definite infection showed odds ratio (OR) 1.145 (95% confidence interval (CI): 1.05-1.25) with an area under the curve of 0.778. PCT had a negative predictive value of 0.95 (95% CI: 0.915-0.988) for definite infection.

CONCLUSIONS

Although PCT was significantly related to the category of infection, it is not sufficiently reliable to be the sole marker of neonatal sepsis. PCT would be useful as part of a full sepsis evaluation, but is relatively expensive. A negative PCT on presentation may rule out sepsis, but this needs to be evaluated further.

Transgenic Pinus radiata from Agrobacterium tumefaciens-mediated transformation of cotyledons

A method for Agrobacterium tumefaciens-mediated transformation of Pinus radiata cotyledon explants was developed using commercially available open-pollinated seed. Pinus radiata is the most widely planted commercial conifer species in the Southern Hemisphere. Reports on transformation of this species have relied on particle bombardment of embryogenic callus derived from immature embryos. The main drawback to the method is the small number of genotypes that are amenable to transformation and regeneration. Since more than 80% of genotypes of radiata pine can be regenerated using cotyledons from mature seed, cotyledon explants were cocultivated with A. tumefaciens strain AGL1 containing a plasmid coding for the neomycin phosphotransferase II (nptII) gene and the beta-glucuronidase (GUS) gene (uidA). Transformed shoots were selected using either geneticin or kanamycin. Critical factors for successful transformation were survival of the cotyledons after cocultivation and selection parameters. Of the 105 putative transformants that were recovered from selection media, 70% were positive for integration of the nptII gene when analysed by PCR. GUS histochemical assay for uidA expression was unreliable because of reaction inhibition by unidentified compounds in the pine needles. Further, only 4 of the 26 independent transformants characterised by PCR and Southern analysis contained an intact copy of both genes. The remaining 22 transformants appeared to have a truncated or rearranged copy of the T-DNA. It is possible that the truncation/rearrangements are due to the Cauliflower mosaic virus (CaMV) 35S promoter. Analysis of the T-DNA junction sites and sequencing of the introduced DNA will help elucidate the nature of T-DNA insertion so that genetic modification of radiata pine can be targeted effectively.

Vinflunine potentiates the activity of cisplatin but not 5-fluorouracil in a transplantable murine adenocarcinoma model

BACKGROUND

Vinflunine is a novel Vinca alkaloid currently undergoing Phase II clinical trials, which have previously demonstrated anti-vascular effects in a transplantable murine colon adenocarcinoma model. Previous studies with compounds showing similar effects in combination with standard anti-cancer agents have demonstrated an improved efficacy relative to the standard agents.

MATERIALS AND METHODS

In this study the synergistic effects of administering vinflunine in combination with either Cisplatin (CPL) or 5-fluorouracil (5-FU) were investigated in a well-differentiated transplantable murine colon adenocarcinoma model (MAC 29).

RESULTS

Vinflunine significantly potentiated the anti-tumour effects of CPL, but had little effect in combination with 5-FU. Using Hoescht 33342 dye labelling of the functional vasculature, clear evidence of vascular shutdown was seen for treatment groups including vinflunine.

CONCLUSION

These data demonstrate that the combination of vinflunine and CPL has significant preclinical anti-tumour activity against a transplantable murine adenocarcinoma model that is related to the anti-vascular effects of vinflunine.

Influence of Agrobacterium tumefaciens strain on the production of transgenic peas ( Pisum sativum L.)

We compared the efficiency of two Agrobacterium tumefaciens strains, AGL 1 and KYRT1, for producing transgenic pea plants. KYRT1 is a disarmed strain of Chry5 that has been shown to be highly tumourigenic on soybean. The efficacies of the strains were compared using cotyledon explants from three pea genotypes and two plasmids. The peas were sourced from field-grown plants over three Southern Hemisphere summer seasons. Overall, KYRT1 was found to be on average threefold more efficient than AGL 1 for producing transgenic plants. We suggest that KYRT1 is sensitive to cocultivation temperature as the expected increase in efficiency was not achieved at high laboratory temperatures.

Combretastatin A-1 phosphate potentiates the antitumour activity of cisplatin in a murine adenocarcinoma model

BACKGROUND

The tubulin depolymerizing drug Combretastatin A-1 phosphate (CA1P), a water-soluble derivative of combretastatin A-1, has been recently shown to have a better efficacy in experimental models than the clinically active, close structural analogue, combretastatin A-4 phosphate (CA4P). Previous studies with CA4P in combination with standard anti-cancer agents have demonstrated improved efficacy relative to the standard agents.

MATERIALS AND METHODS

In this study the synergistic effects of administering CA1P in combination with cisplatin (CPL) in a well-differentiated transplantable murine colon model (MAC 29) was evaluated.

RESULTS

CA1P at 100 mgkg-1 significantly potentiated the anti-tumour effects of CPL. The effect with CPL was similar to that seen for CA1P at its maximum tolerated dose (MTD) alone.

CONCLUSION

These data demonstrate that the combination of CA1P and CPL has significant preclinical antitumour activity against a transplantable murine adenocarcinoma model that is related to the antivascular effects of CA1P.

Antitumour 2-(4-aminophenyl)benzothiazoles generate DNA adducts in sensitive tumour cells in vitro and in vivo

2-(4-Aminophenyl)benzothiazoles represent a potent and highly selective class of antitumour agent. In vitro, sensitive carcinoma cells deplete 2-(4-aminophenyl)benzothiazoles from nutrient media; cytochrome P450 1A1 activity, critical for execution of antitumour activity, and protein expression are powerfully induced. 2-(4-Amino-3-methylphenyl)benzothiazole-derived covalent binding to cytochrome P450 1A1 is reduced by glutathione, suggesting 1A1-dependent production of a reactive electrophilic species. In vitro, 2-(4-aminophenyl)benzothiazole-generated DNA adducts form in sensitive tumour cells only. At concentrations >100 nM, adducts were detected in DNA of MCF-7 cells treated with 2-(4-amino-3-methylphenyl)-5-fluorobenzothiazole (5F 203). 5F 203 (1 microM) led to the formation of one major and a number of minor adducts. However, treatment of cells with 10 microM 5F 203 resulted in the emergence of a new dominant adduct. Adducts accumulated steadily within DNA of MCF-7 cells exposed to 1 microM 5F 203 between 2 and 24 h. Concentrations of the lysylamide prodrug of 5F 203 (Phortress) > or = 100 nM generated adducts in the DNA of sensitive MCF-7 and IGROV-1 ovarian cells. At 1 microM, one major Phortress-derived DNA adduct was detected in these two sensitive phenotypes; 10 microM Phortress led to the emergence of an additional major adduct detected in the DNA of MCF-7 cells. Inherently resistant MDA-MB-435 breast carcinoma cells incurred no DNA damage upon exposure to Phortress (< or = 10 microM, 24 h). In vivo, DNA adducts accumulated within sensitive ovarian IGROV-1 and breast MCF-7 xenografts 24 h after treatment of mice with Phortress (20 mg kg(-1)). Moreover, Phortress-derived DNA adduct generation distinguished sensitive MCF-7 tumours from inherently resistant MDA-MB-435 xenografts implanted in opposite flanks of the same mouse.

Anti-tumor and anti-vascular effects of the novel tubulin-binding agent combretastatin A-1 phosphate

The combretastatins are derived from an African medicinal plant Combretum caffrum (Combretaceae). They have previously been shown to be potent inhibitors of microtubule assembly that cause marked haemorrhagic necrosis in murine subcutaneous tumors. Promising clinical trial results with combretastatin A-4 phosphate led to this investigation of the anti-tumor and anti-vascular effects of a close structural analog, combretastatin A-1 phosphate. This compound caused identical disruption of the tubulin cytoskeleton in HUVECs in vitro at similar concentrations and duration of exposure as combretastatin A-4 phosphate. Treatment of a well-vascularised murine colon adenocarcinoma (MAC 29) with an effective dose (150 mg/kg) of combretastatin A-1 phosphate resulted in a dramatic decrease in functional vascular volume 2 hours after administration. Vascular shutdown was complete within 4 hours after treatment apart from in small areas of the tumor periphery. Morphological examination of hepatic deposits of HT29 and DLD-1 human colon tumors in nude mice demonstrated that combretastatin A-1 phosphate displays greater anti-tumor effects than the A-4 analog at the same dose and this order of activity (A-1 > A-4) is mirrored in the subcutaneous site with the same tumor type. In summary, combretastatin A-1 phosphate can exert its anti-tumor action via an anti-vascular mechanism. The results indicate that, despite having similar in vitro anti-tubulin properties, combretastatin A-1 phosphate seems to have greater in vivo anti-tumor activity than combretastatin A-4 phosphate at the same doses and may therefore be more successful in the clinic.

The intrauterine environment is a strong determinant of glucose tolerance during the neonatal period, even in prematurity

The aim of this study was to determine the contribution of birth weight and gestational age to glucose tolerance in premature neonates. The study group consisted of 100 premature and/or small-for-gestational age infants. Anthropometric measurements were performed both at birth and at the time of a standardized milk feed carried out at 19.6 +/- 12.1 d (range, 1-65 d) after birth. Fasting and postprandial glucose and insulin levels were measured. Birth weight, as a proxy mirror of the intrauterine environment, was found to influence the glucose concentration following a standardized milk feed (beta = -0.46; P = 0.01 for birth weight z-score with 60-min glucose level), whereas gestational age did not. Small-for-gestational age neonates had higher 60-min insulin levels than appropriate-for-gestational age neonates (115.4 +/- 9.5 vs. 68.4 +/- 14.2; P < 0.05) despite similar glucose levels. Neonates born of mothers who were on antihypertensive treatment were smaller and had a higher insulin secretory response than neonates from normotensive mothers. Postnatal growth velocity (kilograms per day) correlated with birth weight (beta = -0.65; P < 0.0001) and insulin resistance (beta = -0.31; P = 0.0004), independently of each other. This study shows that glucose tolerance of the neonate is determined by weight attained at birth irrespective of gestational age and that maternal blood pressure may influence insulin sensitivity of the newborn. Furthermore, catch-up growth in neonates is determined by birth weight and insulin sensitivity.

A comparison of high versus low dose recombinant human erythropoietin versus blood transfusion in the management of anaemia of prematurity in a developing country

The purpose of this study was to evaluate the effectiveness of early treatment with erythropoietin (EPO) in two different treatment regimes (high vs. low dose) in comparison to the conventional treatment of packed red blood cell (PRBC) transfusions in the management of anaemia of prematurity in a country with limited resources. An open controlled trial was conducted on 93 preterm infants (7 days postnatal age, 900-1500 g birthweight). Patients were randomly assigned either to a low dose (250 IU/kg), a high dose (400 IU/kg), or a control group. EPO was administered subcutaneously three times a week and all infants received 6 mg/kg iron orally from study entry to endpoint of therapy. Haematological parameters were measured and compared. The success was defined as an absence of transfusions and a haematocrit that did not fall below 30 per cent during the time period that the infants were in the study. The three groups were statistically comparable at study entry with respect to gestational age, birthweight, Apgar scores, and haematological values. Over the period that the infants were in the study, 75 per cent of the low dose group and 71 per cent of the high dose group met the criteria for success compared with 40 per cent in the control group (p < 0.001). However, there was no significant difference in the number of transfusions when the low and high EPO dose groups (9.5 per cent) were combined and compared with the control group (26.7 per cent) p = 0.0587. It was concluded that in stable infants, 900-1500 g, where phlebotomy losses are minimized and stringent transfusion guidelines are adhered to, EPO does not significantly decrease the number of transfusions. A conservative approach in the management of anaemia of prematurity, is a viable alternative in areas with limited resources.

Combretastatin A-1 phosphate a novel tubulin-binding agent with in vivo anti vascular effects in experimental tumours

In view of the clinical potential of a number of natural products, Combretastatin A-1 phosphate was developed as a water-soluble derivative of combretastatin A-1. This study examined the anti-tumour activity of this compound against an experimental colon tumour (MAC29) in mice. A comparison was made with the clinically active combretastatin A-4 phosphate. The new compound was well-tolerated up to a dose of 250 mg/kg and was more effective at producing tumour growth delays than the A-4 analogue. Significant growth delays were seen at a dose of 50 mg/kg whereas the A-4 phosphate produced no measurable growth delay until a dose of 150 mg/kg was administered. Histological examination of treated tumours indicated that combretastatin A-1 phosphate caused very severe haemorrhagic necrosis in the tumour tissue and analysis of the sections indicated that almost 94 percent of the tumour was dead within 24 hours of treatment. The mechanism of action of combretastatin A-1 phosphate appears to be similar to the A-4 phosphate in that tumour vascular shutdown occurs within 4 hours of treatment. In summary combretastatin A-1 phosphate, the water-soluble analogue of combretastatin A-1, is more potent against a well-vascularised murine colon tumour than its predecessor, combretastatin A-4 phosphate. These data suggest this compound may have potential for clinical development.

Hematological reference ranges in black very low birth weight infants

This study compared hematological reference ranges in black very low birth weight infants to previously published values established predominantly on white subjects. Ninety-four healthy, black, premature babies with a birth weight of 800 to 1500 g at 2-7 days of age were enrolled as part of a study comparing blood transfusions and high- versus low-dose recombinant erythropoietin in anaemia of prematurity. Peripheral venous blood was collected for a full blood count and differential, fetal hemoglobin and erythropoietin levels. The hematological parameters observed in black very low birth weight neonates are similar to previously published reference ranges, except that lower limits of normal were observed for hemoglobin and the red cell indices.

Rapid-extraction oxidation process to recover and reuse copper chromium and arsenic from industrial wood preservative sludge

Chromated copper arsenate (CCA) wood preservative can form insoluble sludges when the hexavalent chromium component is reduced by wood extractives, wood particles and preservative additives in the solution. This sludge accumulates in treating solution work tanks, sumps and in-line filters and must be disposed of as hazardous wastes by waste disposal companies at high costs. A number of commercial sludges were investigated and found to contain 18-94% copper, chromium and arsenic as oxides combined with sand, oil, wood particles, additives and wood extractives. We have developed a multi-stage recycling process whereby approximately 97% of the CCA components are recovered from the sludge. It involves extraction with sodium hypochlorite to remove and oxidize chromium (more than 90%) and extract most of the arsenic (approx. 80%) followed by extraction of the copper and remaining arsenic and chromium with phosphoric acid. The phosphoric acid extract contains some trivalent chromium, which is subsequently oxidized by sodium hypochlorite. The combined oxidized extract containing CrVI, CuII and AsV was compatible with CCA treating solutions and could be re-used commercially for treating wood without having a significant effect on the preservative fixation rate or the leach resistance of the treated wood. A cost analysis showed that the economic savings from recovery of CCA chemicals and reduced landfill costs exceeded the variable costs for materials and energy for the process by as much as Can $966 per tonne of sludge if sodium sulfite can be acquired in bulk quantities for the process.

Is prophylaxis of early-onset group B streptococcal disease appropriate for South Africa?

BACKGROUND

Early-onset group B streptococcal (GBS) disease in neonates can be prevented by the use of intrapartum chemoprophylaxis. There are two prevention strategies, one based on risk factors and the other on culture screening for GBS. This study sought to establish whether GBS chemoprophylaxis is appropriate in a developing country such as South Africa.

METHODS

All neonates with early-onset GBS disease born at Johannesburg Hospital between 1 January 1995 and 21 December 1997 were reviewed. Data were collected prospectively between 1 January and 31 October 1998. Data included demographic information, obstetric information, disease characteristics, admission details and mortality. The approximate cost of implementing both strategies was determined.

RESULTS

The overall incidence of early-onset GBS was 1.16 per 1,000 live births. The rate was significantly greater in 1998 compared with the previous years. Most of the babies were born preterm (70%), and 60% required admission to the neonatal intensive care unit (ICU) (a total of 81 ICU days). Twelve of the babies died. Assuming that chemoprophylaxis would reduce the number of ICU days by half, this would save an amount of R52,000. Culture-based chemoprophylaxis would cost R10 million, whereas an approach based on risk factors would cost R31,140.

CONCLUSION

In conclusion, we feel that early-onset GBS disease is sufficiently prevalent in our unit to justify the implementation of a chemoprophylaxis strategy based on risk factors. Whether other units should adopt a similar approach would depend on the local incidence of early-onset GBS.

Serial interleukin 6 measurements in the early diagnosis of neonatal sepsis

The objective of the present study was to evaluate serial interleukin 6 (IL6) levels in the early diagnosis of neonatal sepsis. Subjects included 255 neonates from the Neonatal Unit of Johannesburg Hospital evaluated for suspected sepsis between February and May 1998. All infants had IL6, full blood count (FBC), C reactive protein (CRP) and blood cultures done at presentation. CRP and IL6 were repeated after 24 h. Infants were categorized into groups according to the likelihood of infection on the basis of clinical presentation, CRP, FBC and culture results, i.e., group 1 (no infection) to group 4 (definite infection). IL6 was compared between the groups by the U-test of Mann-Whitney; stepwise logistic regression was done to establish the best predictors of infection, sensitivity, specificity, positive and negative predictive values were determined. The initial IL6 level was significantly raised in those infants with possible infection [880.67 pg/ml (2966.04), p value 0.0104], probable infection [422.62pg/ml (4077.7), p value 0.0021] and definite infection [11164.39pg/ml (24139.77), p value 0.0000] as compared to those infants without infection [58.65 (182.4)]. The best predictors of infection were the combination of the initial IL6 value and CRP value after 24 h (goodness of fit 97.7 per cent). An initial IL6 value below 20 pg/ml gave a negative predictive value of 90.18 per cent. It is concluded that an IL6 value done at the time of presentation of signs and symptoms suggestive of infection is useful in the early diagnosis of neonatal sepsis. In particular, an initial IL6 value below 20 pg/ml may allow antibiotics to be withheld in a number of infants evaluated for sepsis. There is no benefit in serial determination of IL6 in the diagnosis of neonatal sepsis.

Synthesis and antitumour activity of new derivatives of flavone-8-acetic acid (FAA). Part 4: Variation of the basic structure

A range of 11 derivatives of flavone-8-acetic acid (FAA) in which the structure has been substantially altered in different ways have been prepared and their anti-tumour activity evaluated in vitro against a panel of human and murine tumour cell lines and in vivo against MAC 15A. The generally poor activity observed shows that the basic structure cannot be altered much without destroying the activity.

Use of C-reactive protein to guide duration of empiric antibiotic therapy in suspected early neonatal sepsis

BACKGROUND

Serial C-reactive protein (CRP) measurements have been shown to be useful for guiding duration of antibiotic therapy in neonates. This study sought to determine whether this is a safe and practical approach in a developing country.

METHODS

The study was conducted at the Johannesburg Hospital between September 15, 1998, and January 15, 1999. Subjects included all neonates evaluated for suspected sepsis in the first 24 h of life who had negative initial and repeat CRP values (< or = 10 mg/l) [corrected]. Repeat CRP measurements were performed between 24 and 48 h after birth. Antibiotic therapy was stopped in these infants at 24 to 48 h, and they were observed until 72 h, when the final blood culture results were available. The number of positive blood cultures in this group was determined.

RESULTS

The repeat CRP estimation correctly identified 99 of 100 infants in the study as not requiring further antibiotic therapy (negative predictive value, 99%; 95% confidence intervals, 95.6 to 99.97%). The 1 infant with a positive blood culture was premature with a gestational age of 31 weeks. Eight babies required repeat evaluation for suspected sepsis, 4 presented on Day 3 to 4 and one of these babies died. All these neonates were of < or =33 weeks gestation.

CONCLUSION

The use of serial CRP measurements to guide antibiotic therapy is a safe and practical approach in neonates with suspected sepsis in a developing country.

Determination of histamine in tomatoes by liquid chromatography/mass spectrometry

The histamine level in tomato fruits and pastes was determined by 2 orthogonal techniques as a means of comparing accuracy. Close statistical agreement was found between assays for free histamine by capillary electrophoresis (with UV absorbance detection), and for the dansyl derivative by reversed-phase liquid chromatography (LC). Both techniques have adequate sensitivity for the analysis of endogenous histamine in tomatoes, but LC/electrospray tandem mass spectrometry was more sensitive by at least an order of magnitude, down to a level of 0.05 mg/kg.

HIV-1 co-infection in children hospitalised with tuberculosis in South Africa

SETTING

Hospitals associated with the Department of Paediatrics at the University of the Witwatersrand, Johannesburg, South Africa.

OBJECTIVES

To define the prevalence of human immunodeficiency virus (HIV) co-infection and differences in clinical presentation between HIV-infected and non-infected hospitalised children with tuberculosis.

DESIGN

Children were prospectively enrolled between August 1996 and January 1997.

RESULTS

Of 161 children enrolled, 42% were HIV-infected, including 67/137 with pulmonary tuberculosis (PTB) and 1/24 with extra-pulmonary disease (EPTB). Positive microscopy or bacteriology did not differ by HIV status for children with either PTB or EPTB. Although age did not differ between HIV-infected and non-infected children with PTB, non-HIV-infected children with EPTB were significantly older than those with PTB only (median age 32 months vs 14.5 months, P = 0.004). Chronic weight loss, malnutrition and the absence of BCG scarring were more common in HIV-infected children with PTB. HIV-infected children were also more likely to show cavitation (P = 0.001) and miliary TB (P = 0.01) on chest X-ray. Reactivity to tuberculin (> or = 5 mm and > or = 10 mm in HIV-infected and non-infected children, respectively) was significantly lower in HIV-infected children, as were CD4+ lymphocyte levels. The mortality rate during the study was 13.4% in HIV-infected children compared with 1.5% in non-HIV-infected children (P = 0.03).

CONCLUSIONS

There is a high prevalence of HIV co-infection in children with TB. Progressive PTB and death are more common in HIV-infected children. Tuberculin skin testing is of limited use in screening for TB in HIV-infected children even when using a cut-point of > or = 5 mm.