PPARα and PPARγ Signaling Is Enhanced in the Brain of the Naked Mole-Rat, a Mammal that Shows Intrinsic Neuroprotection from Oxygen Deprivation.

Naked mole-rats (NMRs) are a long-lived animal that do not develop age-related diseases including neurodegeneration and cancer. Additionally, NMRs have a profound ability to consume reactive oxygen species (ROS) and survive long periods of oxygen deprivation. Here, we evaluated the unique proteome across selected brain regions of NMRs at different ages. Compared to mice, we observed numerous differentially expressed proteins related to altered mitochondrial function in all brain regions, suggesting that the mitochondria in NMRs may have adapted to compensate for energy demands associated with living in a harsh, underground environment. Keeping in mind that ROS can induce polyunsaturated fatty acid peroxidation under periods of neuronal stress, we investigated docosahexaenoic acid (DHA) and arachidonic acid (AA) peroxidation under oxygen-deprived conditions and observed that NMRs undergo DHA and AA peroxidation to a far less extent compared to mice. Further, our proteomic analysis also suggested enhanced peroxisome proliferator-activated receptor (PPAR)-retinoid X receptor (RXR) activation in NMRs via the PPARα-RXR and PPARγ-RXR complexes. Correspondingly, we present several lines of evidence supporting PPAR activation, including increased eicosapetenoic and omega-3 docosapentaenoic acid, as well as an upregulation of fatty acid-binding protein 3 and 4, known transporters of omega-3 fatty acids and PPAR activators. These results suggest enhanced PPARα and PPARγ signaling as a potential, innate neuroprotective mechanism in NMRs.

Risk of Bacterial Infection in Patients With Cirrhosis and Acute Variceal Hemorrhage, Based on Child-Pugh Class, and Effects of Antibiotics.

BACKGROUND & AIMS: Antibiotics frequently are overused and are associated with serious adverse events in patients with cirrhosis. However, these drugs are recommended for all patients presenting with acute variceal hemorrhage (AVH). We investigated whether patients should be stratified for antibiotic prophylaxis based on Child-Pugh scores, to estimate risks of bacterial infection, rebleeding, and mortality, and whether antibiotics have equal effects on patients of all Child-Pugh classes. We performed a sensitivity analysis using model for end-stage liver disease (MELD) scores. METHODS: In a retrospective study, we analyzed data from 381 adult patients with cirrhosis and AVH (70% men; mean age, 56 y), admitted from 2000 through 2009 to 2 tertiary care hospitals in Edmonton, Alberta, Canada. We excluded patients with bacterial infection on the day of AVH. The association between antibiotic prophylaxis and outcomes was adjusted by liver disease severity and by a propensity score. RESULTS: The patients included in the study had mean MELD scores of 16, and 54% received antibiotic prophylaxis. Overall, antibiotic therapy was associated with lower risks of infection (adjusted odds ratio, 0.37; 95% confidence interval, 0.91-0.74) and mortality (adjusted odds ratio, 0.63; 95% confidence interval, 0.31-1.29). Among patients categorized as Child-Pugh class A given antibiotics, only 2% developed infections and the mortality rate was 0.4%. Among patients categorized as Child-Pugh class B given antibiotics, 6% developed infections, compared with 14% of patients who did not receive antibiotics; antibiotics did not affect mortality. Administration of antibiotics to patients categorized as Child-Pugh class C reduced infections and mortality by approximately 50%, compared with patients who did not receive antibiotics. MELD scores were not as useful as Child-Pugh class in identifying patients at risk for infection. CONCLUSIONS: Based on a retrospective analysis of patients with cirrhosis and AVH, those categorized as Child-Pugh class A had lower rates of bacterial infection and lower mortality rates in the absence of antibiotic prophylaxis than patients categorized as classes B or C. The recommendation for routine antibiotic prophylaxis for this subgroup requires further evaluation.

Relative survival of patients with non-malignant central nervous system tumours: a descriptive study by the Austrian Brain Tumour Registry.

BACKGROUND: Unlike malignant primary central nervous system (CNS) tumours outcome data on non-malignant CNS tumours are scarce. For patients diagnosed from 1996 to 2002 5-year relative survival of only 85.0% has been reported. We investigated this rate in a contemporary patient cohort to update information on survival. METHODS: We followed a cohort of 3983 cases within the Austrian Brain Tumour Registry. All patients were newly diagnosed from 2005 to 2010 with a histologically confirmed non-malignant CNS tumour. Vital status, cause of death, and population life tables were obtained by 31 December 2011 to calculate relative survival. RESULTS: Overall 5-year relative survival was 96.1% (95% CI 95.1-97.1%), being significantly lower in tumours of borderline (90.2%, 87.2-92.7%) than benign behaviour (97.4%, 96.3-98.3%). Benign tumour survival ranged from 86.8 for neurofibroma to 99.7% for Schwannoma; for borderline tumours survival rates varied from 83.2 for haemangiopericytoma to 98.4% for myxopapillary ependymoma. Cause of death was directly attributed to the CNS tumour in 39.6%, followed by other cancer (20.4%) and cardiovascular disease (15.8%). CONCLUSION: The overall excess mortality in patients with non-malignant CNS tumours is 5.5%, indicating a significant improvement in survival over the last decade. Still, the remaining adverse impact on survival underpins the importance of systematic registration of these tumours.

The Untapped Potential of Comparative Biology in Aging Research: Insights From the Extraordinary-Long-Lived Naked Mole-Rat.

The search for solutions to the vagaries of aging has, historically, been akin to searching at night in the bright light under street lamps by utilizing the few preexisting and well-established animal model systems. Throughout my career as a comparative biologist, I have ventured into the darkness across 4 continents and studied over 150 different animal species, many of which have evolved remarkable adaptations to survive on the harsh and rugged fitness landscape that exists outside of the laboratory setting. In this Fellows Forum, I will discuss the main focus of my research for the last 25 years and dig deeply into the biology of the preternaturally long-lived naked mole-rat that makes it an ideal model system for the characterization of successful strategies to combat aging.

Managing the post-liver transplantation anastomotic biliary stricture: multiple plastic versus metal stents: a systematic review.

BACKGROUND: Anastomotic biliary strictures (ABSs) are common after liver transplantation, especially with living donors. The strategy of balloon dilation and multiple plastic stents (MPSs) is effective in treating ABSs, but requires multiple ERCPs with the associated risks, cost, and patient burden. Covered self-expandable metal stents (SEMSs) have been increasingly used in this setting. However, it is not clear whether there are definite advantages of using SEMSs over MPSs. OBJECTIVE: To compare the efficacy and safety of MPSs and SEMSs in ABS after orthotopic liver transplantation (OLT) and living donor liver transplantation (LDLT). DESIGN: Systematic review by searching MEDLINE and EMBASE databases. PATIENTS: OLT and LDLT patients. INTERVENTIONS: MPSs versus SEMSs. MAIN OUTCOME MEASUREMENTS: Stricture resolution and adverse event rates. RESULTS: Eight studies (446 patients) using MPSs in OLT, 3 studies (120 patients) using MPSs in LDLT, and 10 studies (200 patients) using SEMSs fulfilled the inclusion and exclusion criteria. The stricture resolution rates were highest (94%-100%) when MPS duration was 12 months or longer. The stricture resolution rates with SEMSs in OLT patients were also high when stent duration was 3 months or longer (80%-95%) compared with a duration less than 3 months (53%-88%). Although the overall adverse event rates were low, the overall SEMS migration rate was significant at 16%. LIMITATIONS: No randomized, controlled trials were identified; only small case series using either MPSs or SEMSs were included. CONCLUSIONS: Although SEMSs appeared to be a promising option in the endoscopic management of ABSs after liver transplantation, current evidence does not suggest a clear advantage of SEMS use over MPSs for this indication.

Naked Mole-Rats Demonstrate Profound Tolerance to Low Oxygen, High Carbon Dioxide, and Chemical Pain.

Naked mole-rats (Heterocephalus glaber) are very unusual among subterranean mammals in that they live in large colonies and are extremely social, spending large amounts of time gathered together in underground nests more than a meter below the surface. Many respiring individuals resting in deep, poorly ventilated nests deplete the oxygen supply and increase the concentration of carbon dioxide. Consistent with living in that atmosphere, naked mole-rats tolerate levels of low oxygen and high carbon dioxide that are deadly to most surface-dwelling mammals. Naked mole-rats appear to have evolved a number of remarkable adaptations to be able to thrive in this harsh atmosphere. In order to successfully survive low oxygen atmospheres, they conserve energy utilization by reducing the physiological activity of all organs, manifest by reduced heart rate and brain activity. Amazingly, they resort to the anaerobic metabolism of fructose rather than glucose as a fuel to generate energy when challenged by anoxia. Similarly, high carbon dioxide atmospheres normally cause tissue acidosis, while naked mole-rats have a genetic mutation preventing both acid-induced pain and pulmonary edema. Together, these putative adaptations and the tolerances they provide make the naked mole-rat an important model for studying a host of biomedical challenges.

Detection of subpopulations of leucocytes in different subgroups of semen sample qualities.

The role of leucocytospermia in male subfertility is a much debated topic despite being a frequent finding. This study aimed to identify the role of leucocytes, leucocyte subpopulations and natural killer cells in male subfertility. Seventy-sex subfertile men attending a regional andrology unit were recruited into this prospective study and subdivided into groups based on their semen analysis. The different leucocyte subpopulations were identified using immunocytochemical staining. Significant levels of CD3 helper T lymphocytes (P < 0.001) were present in the oligospermic, asthenospermic, oligoasthenospermic and obstructive azoospermic group compared to the normospermic group. Significant levels of B cells (P < 0.05) were present in the asthenospermic, oligoasthenospermic and obstructive azoospermic group. The natural killer cells (CD56) were significantly raised in the oligoasthenospermic and obstructive azoospermic group (P < 0.05). Our study suggests that leucocytospermia impairs sperm function through enhanced T helper cell modulation, increased B cell population which leads to increased levels of antisperm antibody and natural killer cells mediated sperm damage. The site of seminal leucocyte production is not necessarily confined to the vas or the epididymis.

Leucocyte subpopulations in the seminal plasma and their effects on fertilisation rates in an IVF cycle.

Controversy exists on the role of leucocytospermia on fertilisation rates and IVF outcomes. The aim of our study was to identify the effect of leucocytes and leucocyte subpopulations on fertilisation rates in an IVF cycle. A prospective comparative study of the leucocyte subpopulations of seminal fluid of partners of women attending an IVF cycle was conducted. The samples underwent immunocytochemical staining. The monoclonal antibodies used in this study include CD3, CD4, CD8 (T Cells), CD14 (monocytes/macrophages), CD16 (granulocytes), CD20 (B Cells), CD45 (Pan Leucocytes), CD56 (natural killer cells) and CD69 (activated T and B Cells). Of 21 patients who were recruited into the study, seven were identified as poor fertilisers (<35%) and 14 were identified as good fertilisers (>60%). Data were analysed with SPSS version 14. The total leucocyte counts (CD45) between the poor and good fertilisers were not statistically significant. The macrophages and the monocytes (CD14) were significantly elevated in the good fertilisers group in comparison with the poor fertilisers (P < 0.05). We also found that T cells (CD2, CD4, CD8) and CD14 (macrophages) correlated significantly (r = 0.47, P value < 0.01) with the fertilisation rate. Our study confirms that the presence of leucocytes does not adversely affect the fertilisation rates and the outcome of an IVF cycle. However, macrophages and the monocytes (CD14) were significantly elevated in the good fertilisers group. The increased phagocytic activity in these individuals might increase their fertilising potential by removing spermatozoa with abnormal morphology.

Epigenetic aging of the demographically non-aging naked mole-rat.

The naked mole-rat (NMR) is an exceptionally long-lived rodent that shows no increase of mortality with age, defining it as a demographically non-aging mammal. Here, we perform bisulfite sequencing of the blood of > 100 NMRs, assessing > 3 million common CpG sites. Unsupervised clustering based on sites whose methylation correlates with age reveals an age-related methylome remodeling, and we also observe a methylome information loss, suggesting that NMRs age. We develop an epigenetic aging clock that accurately predicts the NMR age. We show that these animals age much slower than mice and much faster than humans, consistent with their known maximum lifespans. Interestingly, patterns of age-related changes of clock sites in Tert and Prpf19 differ between NMRs and mice, but there are also sites conserved between the two species. Together, the data indicate that NMRs, like other mammals, epigenetically age even in the absence of demographic aging of this species.

Cytokine expression in the seminal plasma and its effects on fertilisation rates in an IVF cycle.

Cytokines are released by various immunocompetent cell subsets in the male urogenital tract and are thought to affect sperm cell function and reproductive process. The aim of the study was to evaluate the levels and a possible role of seven seminal plasma cytokines with fertilisation rates in men attending an in vitro fertilisation (IVF) programme. A total of 36 men of couples who were undergoing traditional IVF in a regional reproductive medicine unit were recruited into this prospective study. Cytokines such as interleukin (IL)-6, IL-8, IL-10, IL-11, IL-12, tumour necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) in the seminal plasma were determined using enzyme linked immunosorbent assay. IL-6, IL-8, IL-10, IL-11 and IFN-γ were detected in all samples. IL-12, and TNF-α were detected in most samples. Levels of IL-11 were significantly higher in the good fertiliser group (P ≤ 0.05). Positive correlation between cytokines such as IL-6 and IL-8 (P < 0.03), IL-10 and IL-11 (P < 0.001) and IFN-γ and IL-10 and IL-11 (P < 0.04 and P < 0.0001 respectively) were found. Our study confirms that the six cytokines other than IL-11 do not affect spermatozoon-oocyte interaction and fertilisation rates in IVF. IL-11 could have a role in the fertilising capacity of the spermatozoa. Significant correlation exists among these cytokines which shows that cytokines rarely act in isolation but rather in a network.

The natural history of inflammatory bowel disease and primary sclerosing cholangitis after liver transplantation--a single-centre experience.

OBJECTIVE: To describe the natural history of primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) after liver transplant, the predictors of PSC and IBD recurrence, and the interaction of these disease processes. METHODS: Data regarding patients who received liver transplants for PSC at the University of Alberta Hospital (Edmonton, Alberta) from 1989 to 2006 were retrospectively reviewed. Recurrent PSC (rPSC) was defined by the Mayo Clinic criteria. Cox proportional hazards modelling and Kaplan-Meier statistics were used. RESULTS: Fifty-nine patients were studied, with a median follow-up of 68 months. A total of 71.2% of patients were diagnosed with IBD pretransplant. Clinical IBD severity post-transplant compared with severity pretransplant was unchanged in 67%, worse in 26.5% and improved in 6.1% of patients. Twenty-five per cent of patients developed rPSC posttransplant. The occurrence of at least one episode of acute cellular rejection (hazard ratio 5.7; 95% CI 1.3 to 25.8) and cytomegalovirus mismatch (hazard ratio 4.2; 95% CI 1.1 to 15.4) were found to be significant predictors of rPSC. Although not statistically significant, there was no rPSC in patients without pre- or post-transplant IBD, and in only one patient with a colectomy. Actuarial patient survival rates at one, five and 10 years posttransplant were 97%, 86% and 79%, respectively. Although a significant proportion of patients experienced worsening IBD post-transplantation, the presence or severity of IBD did not influence rPSC or patient survival. CONCLUSION: Acute cellular rejection and cytomegalovirus mismatch were both identified as independent predictors of rPSC. The impact of steroids and the ideal immunosuppressive regimen for the control of both IBD and PSC post-transplant requires further examination in prospective studies.

Effects of probiotic therapy on portal pressure in patients with cirrhosis: a pilot study.

BACKGROUND: Recent literature has supported the role of bacterial translocation as a mediator of splanchnic vasodilatation and portal hypertension. The objective of this study was to determine whether the probiotic VSL#3 would reduce portal pressure in patients with cirrhosis. METHODS: Eight patients with compensated or very early decompensated cirrhosis and hepatic venous pressure gradient (HVPG) >10 mmHg, received 2 months of VSL#3 (3600 billion bacteria daily). The HVPG, intestinal permeability, endotoxin, tumour necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, renin and aldosterone were measured at baseline and study end. RESULTS: There was no change in the HVPG or intestinal permeability from baseline to study end but there was a trend to reduction in plasma endotoxin (P=0.09), a mild but significant increase in serum TNF-alpha (P=0.02) and a significant reduction in plasma aldosterone (P=0.03). CONCLUSIONS: Within the limitations of small sample size, there does not appear to be a benefit of probiotic therapy for portal pressure reduction in patients with compensated or early decompensated cirrhosis. The reductions in endotoxin and aldosterone suggest possible beneficial effects of probiotics for this patient population. The clinical significance of the small but unexpected increase in TNF-alpha is unclear. Future studies are planned in patients with decompensated cirrhosis.

Comparison between autologous bone grafts and acrylic (PMMA) implants - A retrospective analysis of 286 cranioplasty procedures.

Decompressive craniectomy (DC) is an accepted surgical technique for reducing life-threatening levels of intracranial pressure. Remodelling the cranial vault following DC can constitute a reconstructive challenge and is known to carry significant morbidity. The aim of our study was to evaluate acrylic versus autologous cranioplasty with regard to specific complication rates. A retrospective analysis was conducted of 286 consecutive adult patients who underwent cranioplasty following supratentorial decompressive craniectomy at our institution between January 2003 and June 2013. The patients were followed based on medical records, operative reports, imaging and outpatient contacts in the postoperative course. A total of 221/286 patients in our series received an autologous bone flap. 65/286 cranioplasty procedures were carried out using acrylic (PMMA) implants to cover uni- or bilateral defects. Within the follow-up period a total of 100 operative revisions were performed. 33.3% patients in the autologous bone group and 40.6% of patients in the acrylic group developed complications requiring surgical attention. The main reason for revision was infection with a total of 37 revisions necessary to treat disturbed wound healing. Postoperative sub- and epidural hematomas requiring revision were more frequent in the acrylic group. Resorption of the autologous bone flap requiring operative revision was seen in 8/222 (3.6%) cases. Other complications included loosening of the implant or dislocation. From our data it can be concluded that cranioplasty procedures using autologous bone-flaps and acrylic implants carry signifikant morbidity, but that both are justifiable techniques for cranioplasty in adult patients.

Outcomes of peginterferon alpha-2a and ribavirin hepatitis C therapy in Aboriginal Canadians.

BACKGROUND: There is little published information on baseline characteristics and therapeutic outcomes in hepatitis C virus (HCV)-infected Aboriginal Canadians. It is unclear what proportion of HCV-infected Aboriginal people receive therapy relative to other populations. METHODS: Adults with chronic HCV infection, quantifiable serum HCV-RNA levels and compensated liver disease were assigned, at the physician's discretion, to either 24 or 48 weeks of treatment with peginterferon alpha-2a 180 mug/week plus ribavirin at a dose of 800 mg/day, or 1000 mg/day or 1200 mg/day in an open-label, expanded access program. The primary outcome was sustained virological response, defined as undetectable HCV-RNA by qualitative polymerase chain reaction (less than 50 IU/mL) at the end of 24 weeks of untreated follow-up. Baseline characteristics and outcomes in Aboriginal and non-Aboriginal patients were compared. RESULTS: A total of 2614 patients were eligible for the analysis; 44 individuals (1.7%) self-identified as being of Aboriginal heritage. The baseline characteristics of these two groups were similar. An overall sustained virological response was achieved in 47.7% and 46.5% of Aboriginal and non-Aboriginal patients, respectively. The overall frequencies of adverse events and laboratory abnormalities were similar between the two groups, although cytopenias occurred less frequently in Aboriginal patients. INTERPRETATION: Aboriginal patients were greatly under-represented in the present 'community'-based treatment program, yet viral responses were similar to those of a non-Aboriginal cohort. To increase the uptake of HCV therapy in the Aboriginal population, clarification of the obstacles to treatment is warranted.

Epigenetic repression of RASSF1A but not CASP8 in supratentorial PNET (sPNET) and atypical teratoid/rhabdoid tumors (AT/RT) of childhood.

Supratentorial primitive neuroectodermal tumors (sPNET) and atypical teratoid/rhabdoid tumors (AT/RT) of the CNS represent a biological and clinical enigma, despite advances in both molecular techniques and clinical management for these two rare embryonal brain tumors of childhood. Epigenetic changes hold great potential as possible disease mechanisms and may be manipulated therapeutically. We thus studied aberrant methylation of the genes RASSF1A and CASP8 and its consequence on expression in cell lines and primary tumors using a combination of semiquantitative methylation specific PCR (MSP), bisulfite sequencing and RT-PCR. In all, 17 samples of autopsy-derived normal appearing brain served as controls. Opposed to control tissues 19/24 sPNET and 4/6 AT/RT demonstrated aberrant methylation for the RASSF1A promoter region. Treatment of cell lines using 5-Aza-2'-deoxycytidine (5AZA) alone or in combination with trichostatin A (TSA) succeeded in re-establishing expression of RASSF1A in cell lines derived from a renal rhabdoid, an AT/RT and a medulloblastoma. A 5' CpG-rich region of CASP8 was methylated in normal tissues and in tumors. However, CASP8 showed inconsistent expression patterns in normal and tumor tissues. Our results indicate that aberrant methylation of the RASSF1A promoter region may be of importance in the origin and progression of sPNET and AT/RT while the analysed 5'-CpG rich region of the CASP8 gene does not seem to play an important role in these tumors. Further studies of epigenetic changes in these rare tumors are warranted as their biology remains obscure and treatment efforts have been rather unsuccessfull.

Cervical leukocyte sub-populations in idiopathic preterm labour.

OBJECTIVE: To investigate cervical epithelial leukocyte sub-populations in pregnant women with a history of idiopathic preterm labour. METHODS: A prospective observational study was undertaken of 106 women with a past history of idiopathic preterm delivery following spontaneous labour. A cytobrush was used to sample the epithelium of the cervix at 12-16 weeks of gestation and again 8 weeks later. All women had investigations for cervical and vaginal infection as well as serial transvaginal ultrasonography of their cervix; the mode and gestation at delivery were recorded. Leukocyte sub-populations were examined using immunocytochemistry, and the number of leukocytes per total cell count was calculated. MAIN OUTCOME MEASURES: Cervical epithelial leukocytes populations were (1) described in pregnancy, (2) observed over increasing gestation, (3) analysed in women who developed marked cervical shortening and (4) in those whose preterm labour recurred. RESULTS: There was no significant change in cervical epithelial leukocyte populations during the second trimester of pregnancy. There was no association between cervical leukocytes and cervical shortening. Women with idiopathic preterm labour that recurred had fewer cervical macrophages at the beginning of the second trimester of pregnancy than those whose subsequent pregnancy progressed beyond 35 weeks of gestation. CONCLUSIONS: Cervical epithelial macrophages may serve to prevent recurrent preterm labour, possibly by preventing ascending infection.

Fructose-driven glycolysis supports anoxia resistance in the naked mole-rat.

The African naked mole-rat's (Heterocephalus glaber) social and subterranean lifestyle generates a hypoxic niche. Under experimental conditions, naked mole-rats tolerate hours of extreme hypoxia and survive 18 minutes of total oxygen deprivation (anoxia) without apparent injury. During anoxia, the naked mole-rat switches to anaerobic metabolism fueled by fructose, which is actively accumulated and metabolized to lactate in the brain. Global expression of the GLUT5 fructose transporter and high levels of ketohexokinase were identified as molecular signatures of fructose metabolism. Fructose-driven glycolytic respiration in naked mole-rat tissues avoids feedback inhibition of glycolysis via phosphofructokinase, supporting viability. The metabolic rewiring of glycolysis can circumvent the normally lethal effects of oxygen deprivation, a mechanism that could be harnessed to minimize hypoxic damage in human disease.

Fatal recurrent subarachnoid hemorrhage after complete endovascular aneurysm occlusion.

Endovascular treatment of aneurysms has become an alternative to the neurosurgical approach. Here, we describe a patient presenting with a subarachnoid hemorrhage (SAH) due to a basilar tip aneurysm, which was completely occluded with coils. Fourteen days later the patient died due to massive recurrent SAH. Histologic evaluation showed aneurysm rerupture with coil dislocation in the subarachnoid space. This is a rare histologically documented case of fatal recurrent hemorrhage early after coil embolization of cerebral aneurysms.

Does sustained lung inflation at resuscitation reduce lung injury in the preterm infant?

BACKGROUND: Bronchopulmonary dysplasia (BPD) is a common outcome of preterm birth. Experimental animal work has shown that initial ventilation strategies injure the immature lung and may lead to BPD. Studies with asphyxiated babies have shown that, if tidal ventilation at birth is preceded by sustained lung inflation, larger inflation volumes can be achieved, which is thought to lead to clearance of lung fluid and formation of the functional residual capacity (FRC). OBJECTIVE: To see if sustained lung inflation at initial resuscitation of preterm babies would facilitate the removal of lung fluid, establish the FRC, and allow an even distribution of alveolar opening, permitting less aggressive ventilation, leading to a reduction in pulmonary inflammation and subsequent BPD. METHOD: The outcomes of 52 babies of less than 31 weeks gestation, resuscitated at birth using either a sustained lung inflation of five seconds or a conventional lung inflation of two seconds for the first assisted breath of resuscitation, were examined. Evidence of pulmonary inflammation was determined by quantification of interleukins 6, 10, and 1beta and tumour necrosis factor alpha in bronchoalveolar lavage fluid by enzyme linked immunosorbent assay. RESULTS: There were no significant differences in any of the cytokines. Death occurred in 3/26 babies in the conventional group and 6/26 babies in the sustained lung inflation group. Survival without BPD occurred in 13/26 and 14/26 respectively. CONCLUSION: The use of sustained lung inflation at resuscitation did not reduce lung injury, as measured by inflammatory markers.

Does the use of 50% oxygen at birth in preterm infants reduce lung injury?

BACKGROUND: Bronchopulmonary dysplasia is an inflammatory fibrotic condition produced as a consequence of injurious influences in the neonatal lung. Exposing the premature lung to high concentrations of oxygen is thought to play an important part in lung injury pathogenesis. OBJECTIVE: To see if the amount of oxygen used during resuscitation at birth triggers events that lead to the subsequent lung injury and if a reduction in oxygen used leads to a reduction in lung injury. METHOD: The outcomes of newborn babies less than 31 weeks gestation who were resuscitated using either 50% or 100% oxygen were examined. Eight of the babies receiving 50% oxygen required an increase in their oxygen concentration. Evidence of pulmonary inflammation was determined by quantifying interleukin 6, 1beta, and 10 and tumour necrosis factor alpha in bronchoalveolar lavage fluid by enzyme linked immunosorbent assay. RESULTS: There were no significant differences in any of the cytokines studied in either of the groups. Death occurred in 5/26 (19%) babies who received 100% oxygen and 4/26 (15%) babies who received 50% oxygen. Survival without bronchopulmonary dysplasia at 36 weeks postmenstrual age occurred in 14/26 (54%) and 13/26 (50%). CONCLUSION: Reducing the oxygen to 50% at resuscitation did not influence either short or long term outcomes, but a small benefit could not be excluded. There was no increase in adverse clinical outcomes in babies who received 100% oxygen.