Exploring the Impact of a Trauma-informed Yoga and Mindfulness Curriculum for Multiple Populations: A Pilot Study

Individuals with trauma experience negative mental health impacts and are at risk of poor cardiovascular outcomes. Unmanaged, these conditions may worsen, compromising healing and wellbeing. Yoga, particularly trauma-informed, may improve outcomes. The current pilot study explores the impact of a novel trauma-informed yoga and mindfulness curriculum on wellbeing in two parts. The first examined mental health (stress, mood) outcomes in four trauma-impacted populations: adults who were incarcerated (INC), individuals in recovery from substance use disorders (SU), veterans (VA), and vulnerable youth (YTH) assessing both the impact of individual class participation and impact of attending at least four curriculum sessions. For the subgroup of incarcerated individuals, impact by theme was examined. After curriculum sessions, stress was reduced, and mood improved. Across multiple sessions both the largest decreases in stress and greatest increase in mood occurred after participant in the first session. Further, a specific exploration of curriculum class impact by theme for participants who were incarcerated indicated no difference in impact by theme. The second part of this study explored cardiovascular outcomes for the population of those in recovery from substance use. Reductions in systolic blood pressure occurred immediately after the first curriculum session, and diastolic blood pressure reduced over three consecutive sessions.

Evaluating H295R steroidogenesis assay data for robust interpretation

The in vitro H295R steroidogenesis assay (OECD TG 456) is used to determine a chemical's potential to interfere with steroid hormone synthesis/metabolism. As positive outcomes in this assay can trigger significant higher tiered testing, we compiled a stakeholder database of reference and test item H295R data to characterize assay outcomes. Information concerning whether a Level 5 reproductive toxicity study was triggered due to a positive outcome in the H295R assay was also included. Quality control acceptance criteria were not always achieved, suggesting this assay is challenging to conduct within the guideline specifications. Analysis of test item data demonstrated that pairwise significance testing to controls allowed for overly sensitive statistically significant positive outcomes, which likely contribute to the assay's high positive hit rate. Complementary interpretation criteria (e.g., 1.5-fold change threshold) markedly reduced the rate of equivocal and positive outcomes thus improving identification of robust positive effects in the assay. Finally, a case study (positive H295R outcome and no endocrine adversity in vivo) is presented, which suggests that stricter data interpretation criteria could refine necessary in vivo follow-up testing. Overall, the described additional criteria could improve H295R data interpretation and help inform on how to best leverage this assay for regulatory purposes.

Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

Evidence for neutrino emission from the nearby active galaxy NGC 1068

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy’s active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of 79 − 20 + 22 neutrinos at tera–electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera–electron volt gamma rays from this source.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9}  eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

The Relationship of Lightning Radio Pulse Amplitudes and Source Altitudes as Observed by LOFAR

When a lightning flash is propagating in the atmosphere it is known that especially the negative leaders emit a large number of very high frequency (VHF) radio pulses. It is thought that this is due to streamer activity at the tip of the growing negative leader. In this work, we have investigated the dependence of the strength of this VHF emission on the altitude of such emission for two lightning flashes as observed by the Low Frequency ARray (LOFAR) radio telescope. We find for these two flashes that the extracted amplitude distributions are consistent with a power-law, and that the amplitude of the radio emissions decreases very strongly with source altitude, by more than a factor of 2 from 1 km altitude up to 5 km altitude. In addition, we do not find any dependence on the extracted power-law with altitude, and that the extracted power-law slope has an average around 3, for both flashes.

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100  eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5  eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100  TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100  TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100  TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

Determining Electric Fields in Thunderclouds With the Radiotelescope LOFAR

An analysis is presented of electric fields in thunderclouds using a recently proposed method based on measuring radio emission from extensive air shower events during thunderstorm conditions. This method can be regarded as a tomography of thunderclouds using cosmic rays as probes. The data cover the period from December 2011 till August 2014. We have developed an improved fitting procedure to be able to analyze the data. Our measurements show evidence for the main negative-charge layer near the -10° isotherm. This we have seen for a winter as well as for a summer cloud where multiple events pass through the same cloud and also the vertical component of the electric field could be reconstructed. On the day of measurement of some cosmic-ray events showing evidence for strong fields, no lightning activity was detected within 100 km distance. For the winter events, the top heights were between 5 and 6 km, while in the summer, typical top heights of 9 km were seen. Large horizontal components in excess of 70 kV/m of the electric fields are observed in the middle and top layers.

Radio Emission Reveals Inner Meter-Scale Structure of Negative Lightning Leader Steps

We use the Low Frequency Array (LOFAR) to probe the dynamics of the stepping process of negatively charged plasma channels (negative leaders) in a lightning discharge. We observe that at each step of a leader, multiple pulses of vhf (30-80 MHz) radiation are emitted in short-duration bursts (<10  μs). This is evidence for streamer formation during corona flashes that occur with each leader step, which has not been observed before in natural lightning and it could help explain x-ray emission from lightning leaders, as x rays from laboratory leaders tend to be associated with corona flashes. Surprisingly, we find that the stepping length is very similar to what was observed near the ground, however with a stepping time that is considerably larger, which as yet is not understood. These results will help to improve lightning propagation models, and eventually lightning protection models.

Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1  TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

Constraints on Minute-Scale Transient Astrophysical Neutrino Sources

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5}  erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52}  erg. A hypothetical population of transient sources has to be more common than 10^{-5}  Mpc^{-3}  yr^{-1} (5×10^{-8}  Mpc^{-3}  yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

Search for neutrinos from decaying dark matter with IceCube: IceCube Collaboration

With the observation of high-energy astrophysical neutrinos by the IceCube Neutrino Observatory, interest has risen in models of PeV-mass decaying dark matter particles to explain the observed flux. We present two dedicated experimental analyses to test this hypothesis. One analysis uses 6 years of IceCube data focusing on muon neutrino 'track' events from the Northern Hemisphere, while the second analysis uses 2 years of 'cascade' events from the full sky. Known background components and the hypothetical flux from unstable dark matter are fitted to the experimental data. Since no significant excess is observed in either analysis, lower limits on the lifetime of dark matter particles are derived: we obtain the strongest constraint to date, excluding lifetimes shorter than10 28 s at 90% CL for dark matter masses above 10 TeV .

Measurement of the ν μ energy spectrum with IceCube-79: IceCube Collaboration

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The ν μ energy unfolding described in this paper is based on data taken with IceCube in its 79-string configuration. A sample of muon neutrino charged-current interactions with a purity of 99.5% was selected by means of a multivariate classification process based on machine learning. The subsequent unfolding was performed using the software Truee. The resulting spectrum covers an E ν -range of more than four orders of magnitude from 125 GeV to 3.2 PeV. Compared to the Honda atmospheric neutrino flux model, the energy spectrum shows an excess of more than 1.9 σ in four adjacent bins for neutrino energies E ν ≥ 177.8 TeV . The obtained spectrum is fully compatible with previous measurements of the atmospheric neutrino flux and recent IceCube measurements of a flux of high-energy astrophysical neutrinos.

Constraints on Ultrahigh-Energy Cosmic-Ray Sources from a Search for Neutrinos above 10 PeV with IceCube

We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9}  GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5}  GeV to above 10^{11}  GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6}  GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5}  GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.

Searches for Sterile Neutrinos with the IceCube Detector

The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous ν_{μ} or ν[over ¯]_{μ} disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos experience a strong Mikheyev-Smirnov-Wolfenstein-resonant oscillation. The exclusion limits extend to sin^{2}2θ_{24}≤0.02 at Δm^{2}∼0.3  eV^{2} at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best-fit value of |U_{e4}|^{2}.

Risk assessment of neonatal excipient exposure: lessons from food safety and other areas

Newborn babies can require significant amounts of medication containing excipients intended to improve the drug formulation. Most medicines given to neonates have been developed for adults or older children and contain excipients thought to be safe in these age groups. Many excipients have been used widely in neonates without obvious adverse effects. Some excipients may be toxic in high amounts in which case they need careful risk assessment. Alternatively, it is conceivable that ill-founded fears about excipients mean that potentially useful medicines are not made available to newborn babies. Choices about excipient exposure can occur at several stages throughout the lifecycle of a medicine, from product development through to clinical use. Making these choices requires a scalable approach to analysing the overall risk. In this contribution we examine these issues.

Neonatal extracorporeal membrane oxygenation: practice patterns and predictors of outcome in the UK

OBJECTIVE

To review the UK neonatal extracorporeal membrane oxygenation (ECMO) service and identify predictors of outcome.

DESIGN

Retrospective review of the national cohort.

PATIENTS AND INTERVENTIONS

718 neonates received ECMO for respiratory failure between 1993 and 2005.

MEASUREMENTS AND RESULTS

Diagnoses were: 48.0% meconium aspiration syndrome (97.1% survivors), 15.9% congenital diaphragmatic hernia (CDH; 57.9% survivors), 15.9% sepsis (62.3% survivors), 9.5% persistent pulmonary hypertension (79.4% survivors), 5.6% respiratory distress syndrome (92.5% survivors) and 5.1% congenital lung abnormalities (24.3% survivors). The overall survival rate of 79.7% compared favourably with the worldwide Extracorporeal Life Support Organization (ELSO) Registry. Over the period of review, pre-ECMO use of advanced respiratory therapies increased (p<0.001), but ECMO initiation was not delayed (p = 0.61). The use of veno-venous (VV) ECMO increased (p<0.001) and average run time fell (p = 0.004). Patients treated with VV ECMO had a survival rate of 87.7% compared with 73.4% in the veno-arterial (VA) ECMO group; only 42.4% of those needing conversion from VV to VA ECMO survived. In non-CDH neonates, lower birth weight, lower gestational age, older age at ECMO and higher oxygenation index (OI) were associated with increased risk of death. In CDH neonates, lower birth weight and younger age at ECMO were identified as risk factors for death.

CONCLUSION

The UK neonatal ECMO service achieves good outcomes and with overall survival rate reaching 80% compares favourably with international results. Advanced respiratory therapies are used widely in UK ECMO patients. Identification of higher OI and older age at ECMO as risk factors in non-CDH neonates reinforces the importance of timely referral for ECMO.

Heterogeneity in gene loci associated with type 2 diabetes on human chromosome 20q13.1

Human chromosome 20q12-q13.1 has been linked to type 2 diabetes mellitus (T2DM) in multiple studies. We screened a 5.795-Mb region for diabetes-related susceptibility genes in a Caucasian cohort of 310 controls and 300 cases with T2DM and end-stage renal disease (ESRD), testing 390 SNPs for association with T2DM-ESRD. The most significant SNPs were found in the perigenic regions: HNF4A (hepatocyte nuclear factor 4alpha), SLC12A5 (potassium-chloride cotransporter member 5), CDH22 (cadherin-like 22), ELMO2 (engulfment and cell motility 2), SLC13A3 (sodium-dependent dicarboxylate transporter member 3), and PREX1 (phosphatidylinositol 3,4,5-triphosphate-dependent RAC exchanger 1). Haplotype analysis found six haplotype blocks globally associated with disease (p<0.05). We replicated the PREX1 SNP association in an independent case-control T2DM population and inferred replication of CDH22, ELMO2, SLC13A3, SLC12A5, and PREX1 using in silico perigenic analysis of two T2DM Genome-Wide Association Study data sets. We found substantial heterogeneity between study results.

Referral pattern of neonates with severe respiratory failure for extracorporeal membrane oxygenation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) remains the mainstay of management in neonates with severe but potentially reversible respiratory failure. In the UK, ECMO is available only as a supraregional service at four centres.

OBJECTIVE

To explore regional variations in ECMO referrals and neonatal deaths due to severe respiratory failure in England, Wales and Northern Ireland.

METHODS

In this retrospective study, data regarding ECMO referrals due to neonatal respiratory failure from January to December 2002 were obtained from the four UK ECMO centres and then subdivided according to the Government Office Regions. Anonymised data regarding neonatal deaths was obtained from Confidential Enquiry into Maternal and Child Health. Neonatal deaths were classified into four groups (group 1: deaths potentially avoidable by ECMO; group 2: deaths where it was unclear whether ECMO would have been of benefit; group 3: neonates not eligible for ECMO; and group 4: data inadequate to classify deaths).

RESULTS

There was significant regional variation in the rates of both ECMO referral (0.10 to 0.46 per 1000 live births; (p<0.001)) and neonatal deaths (groups 1 and 2) (0.09 to 0.32 per 1000 live births; (p<0.001)). Regions with high referral rates for ECMO tended towards having higher group 1 plus group 2 neonatal death rates (correlation coefficient = 0.75).

CONCLUSION

It is possible that there are significant regional variations in the uptake of ECMO and in neonatal mortality due to severe respiratory failure. A confidential prospective study may further clarify these observations and identify the factors that might lead to these variations.

Sequential dynamic gadolinium magnetic resonance perfusion-weighted imaging: effects on transit time and cerebral blood volume measurements

PURPOSE

To evaluate if two gadolinium perfusion studies can be performed during the same table occupancy without degradation of the derived data in the second study.

MATERIAL AND METHODS

Magnetic resonance (MR) perfusion studies of the whole brain were performed on 12 patients during the administration of two gadolinium boluses separated by 8 min. In six patients, gadolinium was given as two 20-ml administrations of standard 0.5 M chelate (Magnevist), whilst the other six patients received two 10-ml administrations of 1.0 M chelate (Gadovist).

RESULTS

There were no significant differences in subjective quality between the time-intensity curves of the first and second perfusion studies using either the 0.5 M or 1.0 M gadolinium chelate. The objective measurements in quality of the time-intensity curves (maximum signal change and full width at half maximum) changed by less than 5% of the original values on the second perfusion study. The first-moment mean transit times did not change significantly on the sequential studies. The regional cerebral blood volume tended to increase on the second study (by 15% on average), but this did not reach statistical significance.

CONCLUSION

The results from two sequential dynamic gadolinium-based perfusion studies can be compared in a meaningful manner using the technique described.

Profile of non communicable disease risk factors in an industrial setting

AIM

The profile of non communicable diseases (NCD) risk factors was identified in an industry by pre tested WHO's STEPS questionnaire.

SETTINGS AND DESIGN

A cross-sectional survey of all employment categories of an Industry (2000 employees) was done after randomly selecting subjects (220) from worker (52%) and non worker categories (47.4%), after informed consent.

MATERIALS AND METHODS

Information was collected on behavioural risk factors (STEP I), followed by anthropometric and blood pressure measurements by a trained investigator (STEP II). STEP III constituted biochemical assessment of "at risk" subjects (> 3 risk factors).

STATISTICAL ANALYSIS

Percentage of subjects having NCD risk factors and the odds ratios were calculated.

RESULTS

Overall risk factor profile of the study subjects revealed universal prevalence of 3 risk factors) with prevalence of hypercholesterolemia, hypertension and diabetes of 40.5, 38.2 and 19.1% respectively.

CONCLUSIONS

A high prevalence of NCD risk factors in industrial setting was seen; therefore public health approaches are required at workplace settings to curtail the rising epidemic in the productive populations.

Case report: Mucoepidermoid carcinoma in a patient with congenital agenesis of the left upper lobe

This report describes an unusual case of a mucoepidermoid carcinoma developing in a patient with congenital left upper lobe agenesis. Mucoepidermoid tumours most often develop in major bronchi and present as lobar collapse, post-obstructive pneumonia or as a mass lesion on chest radiography. On CT, the tumour is smooth, well defined, homogeneous and may enhance with intravenous contrast. Tumour calcification has been reported. Lobar agenesis often presents as a co-incidental finding on chest radiography as total or almost complete absence of aeration of the affected lung. Thoracic CT confirms the presence of the underdeveloped lung, pulmonary artery and bronchus and associated mediastinal shift and herniation of the contralateral lung. A literature review of these two conditions is presented.

Fibroblast mitogenic activity of lung lavage fluid from infants with chronic lung disease of prematurity

BACKGROUND

Lung fibrosis is thought to be important in chronic lung disease of prematurity (CLD).

METHODS

Fibroblast proliferative activity was assessed in 207 bronchoalveolar lavage fluid (BALF) samples from 43 infants. Sixteen developed CLD (birth weight 765 g (630-1230), gestation 26.5 weeks (23-29)), 18 developed respiratory distress syndrome (RDS) (birth weight 1415 g (430-4160), gestation 31 weeks (23-39)), and nine control infants (birth weight 2110 g (900-3720), gestation 32 weeks (26-41)) received mechanical ventilation for non-pulmonary reasons.

RESULTS

The fibroblast proliferative activity relative to 10% fetal calf serum was 64-75% in infants with CLD, 55-86% in the RDS group, and 42-68% in control infants during the first 5 weeks of life. Only at day 3 was there a difference between the groups (CLD 72% v control 42%, p < 0.01; RDS 63% v control 42%, p < 0.05). With the use of neutralising antibodies, platelet derived growth factor BB (PDGF-BB) and epidermal growth factor were undetectable, and insulin-like growth factor I (IGF-I) accounted for 14% (p < 0.05) and 11% (p < 0.005) of BALF mitogenic activity from the RDS and CLD groups respectively.

CONCLUSIONS

The mitogenic activity of BALF was similar in the three groups studied and was only partially accounted for by IGF-I. Growth factors other than PDGF-BB and IGF-I contribute significantly to this process.

Potassium channels in human fetal airway smooth muscle cells

Ion channels underlying the resting membrane potential were examined in human fetal airway smooth muscle (ASM). Tissue was obtained from the Medical Research Council Tissue Bank, London, UK. ASM cells were enzymatically dispersed, and ion currents were examined using a patch clamp. Although all cells were of similar size and stained intensely for vimentin, only approximately 50% stained intensely for smooth muscle alpha-actin or myosin heavy chain. Depolarization induced a tetraethylammonium (TEA)- and charybdotoxin (ChTX)-sensitive outward current that varied widely among cells (<50 to >2000 pA at +100 mV), and a smaller nonselective cation current that was similar in all cells (approximately 20 pA at +100 mV). The TEA-sensitive current was associated with three types of large conductance, ChTX-sensitive K+ channel: a 200-pS channel, which was active at negative potentials and low [Ca2+], as described for freshly isolated adult ASM, and two other K+ channels of 100 and 150 pS, previously observed only in adult ASM proliferating in culture. ChTX, but not 4-aminopyridine, caused a substantial depolarization in the current clamp mode, suggesting that, in contrast to ASM from other species or vascular smooth muscle, large conductance K+ channels rather than a delayed rectifier are the major determinant of membrane potential in this tissue. Our results show a distinct similarity between fetal ASM and adult ASM proliferating in culture. We suggest that the heterogeneity in current density and staining reflect different degrees of differentiation, rather than different cell types, and that the 100- and 150-pS K+ channels are specifically associated with a proliferative phenotype in human ASM.

Longitudinal epidemiological study of coronary heart disease in a rural population of Kheda district, Gujarat, India

The present study was undertaken to determine the incidence and related risk factors for coronary heart diseases and hypertension in the rural population of Kheda district, Gujarat (India). The observations from the first five years of this ongoing project (May 1987-May 1992) are described in this paper. Out of an initial sample of 750 individuals in the age group 30-62 years, who were selected by stratified random sampling, 714 persons (males = 429; females = 285) were actually studied, after excluding those suffering from coronary heart diseases (CHD). Initially, all the included subjects were examined clinically and appropriate laboratory investigations were done. A detailed socio-economic history was also obtained. Subsequently all of them were followed up and biannual clinical and laboratory investigations were performed. Cases of CHD were diagnosed according to the recommendations of the New York Heart Association. The overall five-year incidence of CHD was 25.17 per thousand persons. The incidence in males was 3 times higher than in females. More males suffered from myocardial infarction (MI), while in the females the incidence of sudden death was higher (33.3%). The average yearly mortality rate due to CHD was 2.46 per thousand persons. CHD was significantly associated with increased blood pressure (both diastolic and systolic), smoking, and family history of heart disease, and was weakly associated with body weight (p = 0.06).

Binding of tubocurarine to specific serum protein fractions

The binding of tritium-labelled tubocurarine to separate protein fractions of sera from normal subjects and patients with hepatic disease was measured by an electrophoretic technique. The binding of the drug to gamma globulin and albumin solutions also was studied using equilibrium dialysis. The major portion of the drug, 82-90%, was bound to the gamma globulin electrophoretic fraction of both normal and patient sera. However, as measured by equilibrium dialysis, only 15.8% of the drug was bound to the gamma globulin and 23.8% to albumin. Equilibrium dialysis yields the data by which the validity of other methods for measuring drug-protein binding can be judged. Since in a previous study we also found no difference in binding of the drug between healthy individuals and patients with hepatic disease, equilibrium dialysis measurements may reflect better the binding of the drug in vivo.

Plasma protein binding of thiopental in patients with impaired renal or hepatic function

Binding of thiopental to proteins in plasma from healthy, cirrhotic, and uremic subjects was studied using equilibrium dialysis. In plasma from healthy volunteers 28.0 plus or minus 0.9 per cent of thiopental was unbound. In plasma from patients with hepatic disease 53.0 plus or minus 2.1 per cent was unbound, while in patients with renal disease 55.7 plus or minus 1.5 per cent remained unbound. The decreased binding in uremia could not be explained completely by competitive displacement by nitrogenous end products or by hypoalbuminemia, although hypoalbuminemia may account for the decreased binding in cirrhotic patients.