Proteinase inhibitor-inducing factor activity in tomato leaves resides in oligosaccharides enzymically released from cell walls

The synthesis and accumulation of proteinase inhibitor I in excised tomato leaves can be induced with oligosaccharides obtained by fungal endo-alpha-1,4-polygalacturonase digestion of a pectic polysaccharide (M(r) 5000-10,000) isolated from tomato leaves. Active oligosaccharides were also released from isolated tomato leaf cell walls by endopolygalacturonases partially purified from tomato plants. It is suggested that oligosaccharides, released from plant cell wall pectic polysaccharides by either endogenous or exogenous endopolygalacturonases at a wound or infection site, may have hormone-like roles in regulating plant defense responses in unwounded tissues many centimeters away from the site of release.

In vitro synthesis of pre-proteins of vacuolar compartmented proteinase inhibitors that accumulate in leaves of wounded tomato plants

Two proteinase inhibitor proteins that are compartmented in leaf vacuoles (lysosomes) were synthesized in vitro. mRNA was isolated from 17-day-old expanding tomato leaves by extraction with chaotropic buffers followed by chromatography on oligo(dT)-cellulose and was translated with a rabbit reticulocyte lysate system. Preparations of mRNA from leaves of both wounded plants and unwounded plants directed the incorporation of equivalent amounts of label into trichloroacetic acid-precipitable proteins. Only mRNA from leaves of wounded plants directed label into proteins that could be immunoprecipitated with rabbit IgG specific for either inhibitor I or inhibitor II. These results indicate that the wound-induced accumulation of proteinase inhibitors I and II in leaf vacuoles is a result of the presence of translatable mRNA species not present in leaves of unwounded plants. Gel electrophoresis of the immunoprecipitates in NaDodSO(4)/urea/polyacrylamide gels revealed that inhibitors I and II were translated in vitro as precursors about 2000 daltons larger than the inhibitors found in leaves. The presence of the additional polypeptide sequences in the newly synthesized inhibitors indicates that the inhibitors are processed either during or after synthesis, and the presequences may be signal peptides that are part of the process of inhibitor transport into the vacuolar compartments of tomato leaf cells.

Wound-inducible expression of a potato inhibitor II-chloramphenicol acetyltransferase gene fusion in transgenic tobacco plants

A potato inhibitor II gene (IIK) was isolated from a library of potato genes in lambda bacteriophage. An 8-kilobase-pair (kbp) insert was identified using a tomato inhibitor II cDNA as a hybridization probe, and a 2.6-kbp fragment containing the gene was subcloned into the plasmid pUC13 and characterized. The nucleotide sequence of the isolated gene exhibited 87% identity with the wound-inducible tomato inhibitor II cDNA sequence. The amino acid sequence of inhibitor IIK, deduced from the potato gene, exhibited 84% identity with the tomato inhibitor II protein. A 1000-bp restriction fragment from the 5' flanking region of the gene was fused to the open reading frame of the chloramphenicol acetyltransferase (CAT) gene. This fusion was terminated in two ways: (i) with a terminator sequence from the potato inhibitor II gene and (ii) with a terminator from the 6b gene of Ti plasmid pTiA6. These chimeric genes were transferred into tobacco cells via a binary Ti vector system, and transgenic plants were regenerated. The CAT gene was expressed in leaves of transformed plants in response to wounding when fused with the inhibitor IIK promoter and terminator regions. The chimeric gene containing the 6b terminator did not express CAT in response to wounding. The wound-inducible expression of CAT activity was systemic and was induced in tissues distal to the wounded tissues. The time course of wound induction of CAT activity in transgenic tobacco leaves is similar to that found for wound-inducible inhibitor I and II mRNAs in tomato leaves. These results demonstrate that sequences necessary and sufficient for wound inducibility are present within approximately 1000 bp of the control regions of the inhibitor IIK genes and that wound-inducible components of tobacco leaf cells can regulate these sequences.

Uptake of newly introduced universal BCG vaccination in newborns

Universal neonatal BCG vaccination was discontinued in Cork in 1972. Following an outbreak of TB in 2 creches in the HSE South, a universal BCG vaccination program was re-introduced in October 2008. The aim of this study was to determine the vaccination process (in-hospital and community) and the in-hospital uptake of the vaccine. Following informed parental consent, babies of birth weight > 2.5 Kg were eligible for in-hospital vaccination if they were not: febrile, jaundiced on phototherapy, on antibiotics and if not born to HIV- positive mothers. Parents of babies not vaccinated in-hospital were asked to book an appointment in either of the 2 Cork community clinics. The immunisation nurse collected data on BCG vaccination, prospectively. This study examined vaccination uptakes in-hospital and community over a 6 month period (October 2008 to March 2009). There were 4018 deliveries during the study period. In-hospital consent was declined in only 16 babies (<1%) while the in-hospital vaccination uptake was 80% of total liv births. Although 635 newborns were admitted to the NICU, only 46 (8%) were vaccinated while in the NICU. At least 48% of planned community vaccination has been achieved to date. In conclusion, in-hospital consent was almost universal and vaccination uptake was satisfactory. NICU exclusion criteria accounted for a significant proportion of non-vaccination in-hospital. These criteria need to be readdressed considering that all premature babies are given other routine newborn vaccines at 2 months of age, regardless of weight.

Orf: contagious pustular dermatitis

Orf is a common viral infection in sheep. It spreads to humans by direct contact. It is self-limiting, treatment having no beneficial effect. Misdiagnosis by those unfamiliar with its characteristic features is common, and may result in unnecessary treatment with antibiotics or surgery. We present a series of five cases of Orf in children of farmers in the west of Ireland, seen over a 10 year period.

Blood carbon dioxide levels and adverse outcome in neonatal hypoxic-ischemic encephalopathy

We investigated pCO(2) patterns and the relationship between pCO(2) levels and neurodevelopmental outcome in term infants with hypoxic-ischemic encephalopathy. Blood gases during the first 72 hours of life were collected from 52 infants with hypoxic-ischemic encephalopathy. Moderate hypocapnia (pCO(2) <3.3 kPa), severe hypocapnia (pCO(2) <2.6 kPa), and hypercapnia (pCO(2) >6.6 kPa) were correlated to neurodevelopmental outcome at 24 months. Normocapnia was documented in 416/551 (75.5%) of samples and was present during the entire 72 hours in only 6 out of 52 infants. Mean (standard deviation) pCO(2) values did not differ between infants with normal and abnormal outcomes: 5.43 (2.4) and 5.41 (2.03), respectively. There was no significant association between moderate hypocapnia, severe hypocapnia, or hypercapnia and adverse outcome (odds ratio [OR] = 1.84, 95% confidence interval [CI] = 0.49 to 6.89; OR = 3.16, CI = 0.14 to 28.45; and OR = 1.07, CI = 0.24 to 5.45, respectively). In conclusion, only one in nine newborns had normocapnia throughout the first 72 hours. Severe hypocapnia was rare and occurred only in ventilated babies. Hypercapnia and hypocapnia in infants with hypoxic-ischemic encephalopathy during the first 72 hours of life were not associated with adverse outcome.

Programming infant gut microbiota: influence of dietary and environmental factors

The neonatal period is crucial for intestinal colonisation, and the composition of this ecosystem in early life is influenced by such factors as mode of birth, environment, diet and antibiotics. The intestinal microbiota contributes to protection against pathogens, maturation of the immune system and metabolic welfare of the host, but under some circumstances can contribute to the pathogenesis of certain diseases. Because colonisation with non-pathogenic microbiota is important for infant health and may affect health in later life, it is important to understand how the composition of this microbial organ is established and by which dietary means (e.g. supplementation with prebiotics/probiotics/food ingredients) it can be programmed in order to achieve an ecosystem that is valuable for the host.

Using standardized patients to assess communication skills in medical and nursing students

BACKGROUND

A number of recent developments in medical and nursing education have highlighted the importance of communication and consultation skills (CCS). Although such skills are taught in all medical and nursing undergraduate curriculums, there is no comprehensive screening or assessment programme of CCS using professionally trained Standardized Patients Educators (SPE's) in Ireland. This study was designed to test the content, process and acceptability of a screening programme in CCS with Irish medical and nursing students using trained SPE's and a previously validated global rating scale for CCS.

METHODS

Eight tutors from the Schools of Nursing and Medicine at University College Cork were trained in the use of a validated communication skills and attitudes holistic assessment tool. A total of forty six medical students (Year 2 of 5) and sixty four nursing students (Year 2/3 of 4) were selected to under go individual CCS assessment by the tutors via an SPE led scenario. Immediate formative feedback was provided by the SPE's for the students. Students who did not pass the assessment were referred for remediation CCS learning.

RESULTS

Almost three quarters of medical students (33/46; 72%) and 81% of nursing students (56/64) passed the CCS assessment in both communication and attitudes categories. All nursing students had English as their first language. Nine of thirteen medical students referred for enhanced learning in CCS did not have English as their first language.

CONCLUSIONS

A significant proportion of both medical and nursing students required referral for enhanced training in CCS. Medical students requiring enhanced training were more likely not to have English as a first language.

The predictive value of early neurological examination in neonatal hypoxic-ischaemic encephalopathy and neurodevelopmental outcome at 24 months

AIM

The clinical and electrographic signs of hypoxic-ischaemic encephalopathy (HIE) evolve over the first days of life. We examined the evolution of neurological signs over the first 3 days of life, and determined whether serial administration of the Amiel-Tison Neurological Assessment at Term (ATNAT) would predict neurodevelopmental outcome at 24 months.

METHOD

Term (>37 wks' gestation) neonates born with suspected HIE between May 2003 and May 2005 in a Cork maternity unit were recruited prospectively. Modified Sarnat grading was assigned. The ATNAT was administered on days 1, 2, and 3 of life and a discharge neurological examination. Time to oral feeding and demographic variables were recorded. Developmental status was assessed using the revised Griffiths Mental Development Scales at 6, 12, and 24 months.

RESULTS

Fifty-seven infants were recruited, with 51 (31 males, 20 females) included for follow-up. Neurological examination evolved and normalized over the first 3 days of life in many cases. At 24 months, 21 children had an adverse outcome, including six deaths. Examination at all time points correlated significantly with neurological outcome at 24 months. The best correlations were found to be (1) neurological examination at discharge (r=0.65, p<0.001), (2) Sarnat grading (r=0.64, p<0.001), and (3) ATNAT on day 3 (r=0.46, p<0.001). The best predictive value was seen with neurological examination at discharge (positive and negative predictive values of 86% and 72% respectively).

INTERPRETATION

Persistence of abnormal neurological signs correlates significantly with adverse outcome. The later a neonatal neurological examination was performed, the better its predictive ability.

Placental malaria and lack of prenatal care in an area of unstable malaria transmission in eastern Sudan

A cross-sectional study was conducted in Gadarif Hospital in eastern Sudan to determine the prevalence, and evaluate the risk factors, of placental malaria. Two hundred and thirty-six delivering women were enrolled in the study. Socio-demographic characteristics were gathered through questionnaires. Maternal hemoglobin was measured, ABO blood groups were determined, and placental histological examinations for malaria were performed. The birth weight of the newborn was also recorded. The mean (SD) maternal age was 25.5 (6.0) yr and the mean (SD) hemoglobin was 9.8 (0.9) g/dl. Placental histology showed acute malaria infections in 13 (5.5%) and chronic infections in 5 (2.1%) women; 28 (11.9%) of the placentas revealed past infection and 190 (80.5%) indicated no infection. Lack of prenatal care was significantly associated with placental infections (OR = 12.0, 95% CI = 2.3-16.2; P = 0.003). There was no significant association between placental malaria infections and maternal age, parity, and blood group. Thirty-two (13.5%) of these pregnancy outcomes resulted in low birthweight babies. There was, however, no significant association between placental malaria and low birth weight (OR = 2.0, 95% CI = 0.4-4.1; P = 0.1). Thus, placental malaria infections affect pregnant women in this area of eastern Sudan regardless of their age or parity. Prenatal care should be encouraged to reduce malaria in the area. Much more research regarding malaria and pregnancy is needed.

Benchmarking care for very low birthweight infants in Ireland and Northern Ireland

BACKGROUND

Benchmarking is that process through which best practice is identified and continuous quality improvement pursued through comparison and sharing. The Vermont Oxford Neonatal Network (VON) is the largest international external reference centre for very low birth weight (VLBW) infants. This report from 2004-7 compares survival and morbidity throughout Ireland and benchmarks these results against VON.

METHODS

A standardised VON database for VLBW infants was created in 14 participating centres across Ireland and Northern Ireland.

RESULTS

Data on 716 babies were submitted in 2004, increasing to 796 babies in 2007, with centres caring for from 10 to 120 VLBW infants per year. In 2007, mortality rates in VLBW infants varied from 4% to 19%. Standardised mortality ratios indicate that the number of deaths observed was not significantly different from the number expected, based on the characteristics of infants treated. There was no difference in the incidence of severe intraventricular haemorrhage between all-Ireland and VON groups (5% vs 6%, respectively). All-Ireland rates for chronic lung disease (CLD; 15-21%) remained lower than rates seen in the VON group (24-28%). The rates of late onset nosocomial infection in the all-Ireland group (25-26%) remained double those in the VON group (12-13%).

DISCUSSION

This is the first all-Ireland international benchmarking report in any medical specialty. Survival, severe intraventricular haemorrhage and CLD compare favourably with international standards, but rates of nosocomial infection in neonatal units are concerning. Benchmarking clinical outcomes is critical for quality improvement and informing decisions concerning neonatal intensive care service provision.

Experimental approximation of the Jones polynomial with one quantum bit

We present experimental results approximating the Jones polynomial using 4 qubits in a liquid state nuclear magnetic resonance quantum information processor. This is the first experimental implementation of a complete problem for the deterministic quantum computation with one quantum bit model of quantum computation, which uses a single qubit accompanied by a register of completely random states. The Jones polynomial is a knot invariant that is important not only to knot theory, but also to statistical mechanics and quantum field theory. The implemented algorithm is a modification of the algorithm developed by Shor and Jordan suitable for implementation in NMR. These experimental results show that for the restricted case of knots whose braid representations have four strands and exactly three crossings, identifying distinct knots is possible 91% of the time.

Potential hazard of the Neopuff T-piece resuscitator in the absence of flow limitation

OBJECTIVE

(1) To assess peak inspiratory pressure (PIP), positive end expiratory pressure (PEEP) and maximum pressure relief (P(max)) at different rates of gas flow, when the Neopuff had been set to function at 5 l/min. (2) To assess maximum PIP and PEEP at a flow rate of 10 l/min with a simulated air leak of 50%.

DESIGN

5 Neopuffs were set to a PIP of 20, PEEP of 5 and P(max) of 30 cm H(2)O at a gas flow of 5 l/min. PIP, PEEP and P(max) were recorded at flow rates of 10, 15 l/min and maximum flow. Maximum achievable pressures at 10 l/min gas flow, with a 50% air leak, were measured.

RESULTS

At gas flow of 15 l/min, mean PEEP increased to 20 (95% CI 20 to 21), PIP to 28 (95% CI 28 to 29) and the P(max) to 40 cm H(2)O (95% CI 38 to 42). At maximum flow (85 l/min) a PEEP of 71 (95% CI 51 to 91) and PIP of 92 cm H(2)O (95% CI 69 to 115) were generated. At 10 l/min flow, with an air leak of 50%, the maximum PEEP and PIP were 21 (95% CI 19 to 23) and 69 cm H(2)O (95% CI 66 to 71).

CONCLUSIONS

The maximum pressure relief valve is overridden by increasing the rate of gas flow and potentially harmful PIP and PEEP can be generated. Even in the presence of a 50% gas leak, more than adequate pressures can be provided at 10 l/min gas flow. We recommend the limitation of gas flow to a rate of 10 l/min as an added safety mechanism for this device.

The pool chlorine hypothesis and asthma among boys

Swimming pool sanitation has largely been concerned with the microbiological quality of pool water, which is normally treated using a number of chlorine products. Recent studies have pointed to the potential hazards of chlorine by-products to the respiratory epithelium, particularly in indoor, poorly ventilated, pools. The aim of our study was to elucidate whether chronic exposure to indoor chlorinated swimming pools was associated with an increased likelihood of the development of asthma in boys.

METHODS

The subjects were boys aged between 6 and 12 years. Data was collected by means of parental responses to a standardized asthma questionnaire (ISAAC: International Study of Asthma and Allergies in Childhood), supplemented with additional questions regarding frequency of attendance, number of years attendance, whether the child is a swimming team member. The questionnaire return rate was 71/% (n = 121). 23 boys were excluded on the basis that they had asthma before they started swimming (n = 97). There was a significant association between number of years a boy had been swimming and the likelihood of wheezing in the last 12 months (p = 0.009; OR = 1.351; 95% CI = 1.077-1.693) and diagnosed asthma (p = 0.046; OR = 1.299; 95% CI = 1.004-1.506). The greater the number the number of years a boy had been attending an indoor, chlorinated pool, the greater the likelihood of wheezing in the last 12 months or "had asthma". Age, parental smoking habits and being a swimming team member had no association with any of the asthma variables examined. Swimming pool attendance may be a risk factor in asthma in boys.

Neonatal resuscitation program guidelines 2006: ready, steady, can't go!

New evidence-based guidelines have been launched with recommendations that may impact how resuscitations, particularly of LBW infants, are enacted.

AIM

to determine current resuscitation practices in Maternity units in Ireland and benchmarked these results to a recent study in the United States.

METHODS

A 20-question survey was developed and mailed to a lead neonatologist/paediatrician in each of 19 maternity units in Ireland in May 2006.

RESULTS

There was 84% response rate to the surveys mailed which included 10 level II and 6 level III units. NRP qualification was considered obligatory for all paediatrics doctors in all units, with 14/16 units running at least one NRP course per year (range 1-9). Self inflating bags were more commonly used (44%), followed by T-piece resuscitators (31%) and flow inflating bags (25%). Pulse oximeters to alter the fraction of inspired oxygen were used by (25%) of units during the management of very low birth weigh infants, with a useful signal being achieved in one minute in most cases. Air/oxygen blenders were available for (44%) of units; however, all units use 100% O2 for initial resuscitation. CO2 detectors for ETT position were used in only 2 units (12%). A third of units (31%) used plastic wrap to prevent heat loss in VLBW infants. CPAP/PEEP were used by 44% of the surveyed units, generally with initiating pressure of 5 cm H2O.

CONCLUSIONS

NRP is now an obligatory feature in all NICU's in Ireland compared to the 1990s when resuscitation training was disorganized and inconsistent. Variations in resuscitation practices still exist among different units. Many units may not be able to apply 2006 NRP guidelines especially for VLBW infants unless there is a significant investment in air/oxygen blenders, pulse oximeters, CO2 detectors and resuscitators that control peak pressures and CPAP/PEEP.

Persistent lactic acidosis in neonatal hypoxic-ischaemic encephalopathy correlates with EEG grade and electrographic seizure burden

BACKGROUND

Predicting at birth which infants with perinatal hypoxic-ischaemic injury will progress to significant encephalopathy remains a challenge.

OBJECTIVE

To determine whether lactic acidosis at birth in asphyxiated neonates could predict the grade of EEG encephalopathy by examining the relationship between time taken for the normalisation of lactate, severity of encephalopathy and seizure burden.

METHODS

Continuous early video-EEG monitoring was performed in babies at risk for hypoxic-ischaemic encephalopathy. Encephalopathy was graded from the EEG data. Total seizure burden (seconds) was calculated for each baby. Initial blood gas measurements of pH, base deficit and lactate were taken within 30 minutes of delivery. Time to normal serum lactate was determined in hours from birth for each infant.

RESULTS

All 50 term infants had raised initial serum lactate (median (lower, upper quartiles) 11.7 (10.2, 14.9)). There were no significant differences between the initial serum lactate, pH and base deficit in infants with normal/mildly abnormal (n = 24), moderately abnormal (n = 14), severely abnormal (n = 5) and inactive EEGs (n = 7). Time to normal lactate varied significantly with EEG grade (median (lower, upper quartile) 6.0 (4.1, 9.5) for mild/normal EEG, 13.5 (6.8, 23.5) moderate EEG, 41.5 (30.0, 55.5) severe group, 12.0 (8.1, 21.5) inactive group; p<0.001). Time to normal lactate correlated significantly with EEG seizure burden (seconds; R = 0.446, p = 0.002). Mean (SD) time to normal lactate was 10.0 (7.2) hours in infants who did not have seizures and 27.3 (19.0) hours in the 13 infants with electrographic seizures (p = 0.002).

CONCLUSIONS

Serum lactate levels in the first 30 minutes of life do not predict the severity of the ensuing encephalopathy. In contrast, sustained lactic acidosis is associated with severe encephalopathy on EEG and correlates with seizure burden.

Defining the gap between electrographic seizure burden, clinical expression and staff recognition of neonatal seizures

BACKGROUND

Neonatal seizures are often subclinical, making accurate diagnosis difficult.

OBJECTIVE

To describe the clinical manifestations of electrographic seizures recorded on continuous video-EEG, and to compare this description with the recognition of clinical seizures by experienced neonatal staff.

METHODS

Term infants, at risk of seizures, were monitored by continuous 12-channel video-EEG from <6 hours of birth for up to 72 hours. All clinical seizures were recorded by experienced neonatal staff on individual seizure charts. Video-EEG recordings were subsequently analysed. The number, duration and clinical expression of electrographic seizures were calculated (in seconds), and compared with the seizures clinically suspected by the neonatal staff.

RESULTS

Of 51 infants enrolled, nine had electrographic seizures. A further three had clinically suspected seizures, without associated electrographic abnormality. Of the total 526 electrographic seizures, 179 (34%) had clinical manifestations evident on the simultaneous video recording. The clinical seizure activity corresponded to 18.8% of the total electrographic seizure burden. Overdiagnosis also occurred frequently. Of the 177 clinically suspected seizure episodes documented by staff, 48 (27%) had corresponding electrographic evidence of seizure activity Thus, only 9% (48/526) of electrographic seizures were accompanied by clinical manifestations, which were identified and documented by neonatal staff.

CONCLUSION

Only one-third of neonatal EEG seizures displays clinical signs on simultaneous video recordings. Moreover, two-thirds of these clinical manifestations are unrecognised, or misinterpreted by experienced neonatal staff. In the recognition and management of neonatal seizures clinical diagnosis alone is not enough.

Doctors' and nurses' attitudes towards neonatal ethical decision making in Ireland

OBJECTIVE

To explore the clinical staff attitudes towards ethical decision making in neonatal intensive care units (NICUs) in Ireland, to establish differences between doctors and nurses and to compare attitudes in Ireland with those in Europe.

DESIGN

Cross-sectional study by means of an anonymous questionnaire. 64 doctors and 228 nurses in seven NICUs participated (response rates 74% and 81%, respectively). Through factor analysis the staff answers to 12 attitude statements were used to build a score whose range varied from 0 (preservation of life in any case) to 10, indicating a more individualised approach according to the patient's best interests.

MAIN OUTCOME MEASURE

Staff attitudes to ethical decision making in NICU.

RESULTS

Mean values of attitude scores were 5.8 (95% CI 5.3 to 6.2) for doctors, and 6.0 (95% CI 5.5 to 6.5) for nurses. Respondents with experience in follow-up of NICU graduates had significantly higher scores (6.7 vs 5.4, p = 0.018), while the opposite was true among more religious staff (5.8 vs 6.9, p = 0.026) and particularly for minority religions such as Muslim (4.1, 95% CI 3.1 to 5.2). Scores were higher after age 30 for nurses, and after age 40 for doctors, suggesting the adoption of a less vitalistic viewpoint as respondents grow older and more experienced. Among doctors, a relationship was found between the attitude score and their self-reported non-treatment practices.

CONCLUSIONS

In Ireland, NICU doctors and nurses hold similar attitudes towards ethical decision making. Personal and professional factors have a statistically significant impact on attitude score. Compared with the rest of Europe, attitudes in Ireland appear more similar to those of southern rather than northern European countries.

Spin based heat engine: demonstration of multiple rounds of algorithmic cooling

We experimentally demonstrate multiple rounds of heat-bath algorithmic cooling in a 3 qubit solid-state nuclear magnetic resonance quantum information processor. By pumping entropy into a heat bath, we are able to surpass the closed system limit of the Shannon bound and purify a single qubit to 1.69 times the heat-bath polarization. The algorithm combines both high fidelity coherent control and a deliberate interaction with the environment. Given this level of quantum control in systems with larger reset polarizations, nearly pure qubits should be achievable.