Finding the fifth intercostal space for chest drain insertion: guidelines and ultrasound.

OBJECTIVES: International guidelines exist for chest drain insertion and recommend identifying the fifth intercostal space or above, around the midaxillary line. In a recent study, applying these guidelines in cadavers risked insertion in the 6th intercostal space or below in 80% of cases. However, there are limitations of cadaveric studies and this investigation uses ultrasound to determine the intercostal space identified when applying these guidelines in healthy adult volunteers. METHODS: On each side of the chest wall in 31 volunteers, the position for drain insertion was identified using the European Trauma Course method, Advanced Trauma Life Support (ATLS) method, British Thoracic Society's 'safe triangle' and the 'traditional' method of palpation. Ultrasound imaging was used to determine the relationship of the skin marks with the underlying intercostal spaces. RESULTS: Five methods were assessed on 60 sides. In contrast to the cadaveric study, 94% of skin marks lay over a safe intercostal space. However, the range of intercostal spaces found spanned the second to the seventh space. In 44% of women, the inferior boundary of the 'safe triangle' and the ATLS guidelines located the sixth intercostal space or below. CONCLUSIONS: Current guidelines often identify a safe site for chest drain insertion, although the same site is not reproducibly found. In addition, women appear to be at risk of subdiaphragmatic drain insertion when the nipple is used to identify the fifth intercostal space. Real-time ultrasonography can be used to confirm the intercostal space during this procedure, although a safe guideline is still needed for circumstances in which ultrasound is not possible.

Oral contraceptive and reproductive risk factors for ovarian cancer within sisters in the breast cancer family registry.

BACKGROUND: Oral contraceptive use has been consistently associated with a reduced risk of ovarian cancer in unrelated, average risk women; however little data exist on whether this benefit extends to higher risk women from cancer families. To examine this, we conducted family-based analyses using the Breast Cancer Family Registry. METHODS: We used generalised estimating equations to obtain the population average effect across all families (n=389 cases, n=5643 controls) and conditional logistic regression to examine within-family differences in a subset with at least two sisters discordant on ovarian cancer status (n=109 cases, n=149 unaffected sister controls). RESULTS: In the multivariable generalised estimating equation model there was a reduced risk of ovarian cancer for ever use of oral contraceptives compared with never use (OR=0.58, 95% CI: 0.37, 0.91), and in the conditional logistic model there was a similar inverse association; however, it was not statistically significant (OR=0.52, 95% CI: 0.23, 1.17). We examined this association by BRCA1/2 status and observed a statistically significant reduced risk in the non-carriers only. CONCLUSION: We observed a decreased risk of ovarian cancer with oral contraceptive use supporting that this association observed in unrelated women extends to related women at higher risk.

Impact of introducing practical obstetric multi-professional training (PROMPT) into maternity units in Victoria, Australia.

OBJECTIVE: To assess the introduction of Practical Obstetric Multi-professional Training (PROMPT) into maternity units and evaluate effects on organisational culture and perinatal outcomes. DESIGN: A retrospective cohort study. SETTING: Maternity units in eight public hospitals in metropolitan and regional Victoria, Australia. POPULATION: Staff in eight maternity units and a total of 43,408 babies born between July 2008 and December 2011. METHODS: Representatives from eight Victorian hospitals underwent a single day of training (Train the Trainer), to conduct PROMPT. Organisational culture was compared before and after PROMPT. Clinical outcomes were evaluated before, during and after PROMPT. MAIN OUTCOME MEASURES: The number of courses run and the proportion of staff trained were determined. Organisational culture was measured using the Safety Attitude Questionnaire. Clinical measures included Apgar scores at 1 and 5 minutes (Apgar 1 and Apgar 5), cord lactate, blood loss and length of baby's stay in hospital. RESULTS: Seven of the eight hospitals conducted PROMPT. Overall about 50% of staff were trained in each year of the study. Significant increases were found in Safety Attitude Questionnaire scores representing domains of teamwork (Hedges' g 0.27, 95% confidence interval [95% CI] 0.13-0.41), safety (Hedges' g 0.28, 95% CI 0.15-0.42) and perception of management (Hedges' g 0.17, 95% CI 0.04-0.31). There were significant improvements in Apgar 1 (OR 0.84, 95% CI 0.77-0.91), cord lactates (odds ratio 0.92, 95% CI 0.85-0.99) and average length of baby's stay in hospital (Hedges' g 0.03, 95% CI 0.01-0.05) during or after training, but no change in Apgar 5 scores or proportion of cases with high blood loss. CONCLUSION: PROMPT can be introduced using the Train the Trainer model. Improvements in organisational culture and some clinical measures were observed following PROMPT.

Small angle neutron scattering on an absolute intensity scale and the internal surface of diatom frustules from three species of differing morphologies.

The internal nanostructure of the diatoms Cyclotella meneghiniana, Seminavis robusta and Achnanthes subsessilis was investigated using small angle neutron scattering (SANS) to examine thin biosilica samples, consisting of isotropic (powder) from their isolated cell walls. The interpretation of SANS data was assisted by several other measurements. The N2 adsorption, interpreted within the Branuer-Emmet-Teller isotherm, yielded the specific surface area of the material. Fourier transform infrared (FTIR) and Raman spectroscopy indicates that the isolated material is amorphous silica with small amounts of organic cell wall materials acting as a filling material between the silica particles. A two-phase (air and amorphous silica) model was used to interpret small angle neutron scattering data. After correction for instrumental resolution, the measurements on two SANS instruments covered an extended range of scattering vectors 0.0011 nm(-1) < q < 5.6 nm(-1), giving an almost continuous SANS curve over a range of scattering vectors, q, on an absolute scale of intensity for each sample. Each of the samples gave a characteristic scattering curve where log (intensity) versus log (q) has a -4 dependence, with other features superimposed. In the high-q regime, departure from this behaviour was observed at a length-scales equivalent to the proposed unitary silica particle. The limiting Porod scattering law was used to determine the specific area per unit of volume of each sample illuminated by the neutron beam. The Porod behaviour, and divergence from this behaviour, is discussed in terms of various structural features and the proposed mechanisms for the bio-assembly of unitary silica particles in frustules.

Microbiome-scale analysis of aerosol facemask contamination during nebulization therapy in hospital.

BACKGROUND: Microbial contamination of aerosol facemasks could be a source of nosocomial infections during nebulization therapy in hospital, prompting efforts to identify these contaminants. Identification of micro-organisms in medical devices has traditionally relied on culture-dependent methods, which are incapable of detecting the majority of these microbial contaminants. This challenge could be overcome with culture-independent sequencing-based techniques that are suited for the profiling of complex microbiomes. AIM: To characterize the microbial contaminants in aerosol facemasks used for nebulization therapy, and identify factors influencing the composition of these microbial contaminants with the acquisition and analysis of comprehensive microbiome-scale profiles using culture-independent high-throughput sequencing. METHODS: Used aerosol facemasks collected from hospitalized patients were analysed with culture-independent 16S rRNA gene-based amplicon sequencing to acquire microbiome-scale comprehensive profiles of the microbial contaminants. Microbiome-based analysis was performed to identify potential sources of microbial contamination in facemasks. FINDINGS: Culture-independent high-throughput sequencing was demonstrated for the capacity to acquire microbiome-scale profiles of microbial contaminants on aerosol facemasks. Microbial source identification enabled by the microbiome-scale profiles linked microbial contamination on aerosol facemasks to the human skin and oral microbiota. Antibiotic treatment with levofloxacin was found to reduce contamination of the facemasks by oral microbiota. CONCLUSION: Sequencing-based microbiome-scale analysis is capable of providing comprehensive characterization of microbial contamination in aerosol facemasks. Insight gained from microbiome-scale analysis facilitates the development of effective strategies for the prevention and mitigation of the risk of nosocomial infections arising from exposure to microbial contamination of aerosol facemasks, such as targeted elimination of potential sources of contamination.

Microbiome-based source identification of microbial contamination in nebulizers used by inpatients.

Nebulizers are essential for the delivery of aerosolized medication for respiratory patients in hospital. Microbial contamination of nebulizers increases the risk of healthcare-associated infections, presenting the critical need to identify sources of contamination in order to develop effective infection prevention and control practices in hospitals. Using an innovative microbiome-based cultivation-independent microbial source identification technique, the hospital indoor environment was identified as a significant source contributing to microbial contaminants in nebulizers, providing important information to develop strategies for targeted decontamination and enhance the effectiveness of infection prevention and control practices.

Spatial and Temporal Diversity of Astrocyte Phenotypes in Spinocerebellar Ataxia Type 1 Mice.

While astrocyte heterogeneity is an important feature of the healthy brain, less is understood about spatiotemporal heterogeneity of astrocytes in brain disease. Spinocerebellar ataxia type 1 (SCA1) is a progressive neurodegenerative disease caused by a CAG repeat expansion in the gene Ataxin1 (ATXN1). We characterized astrocytes across disease progression in the four clinically relevant brain regions, cerebellum, brainstem, hippocampus, and motor cortex, of Atxn1154Q/2Q mice, a knock-in mouse model of SCA1. We found brain region-specific changes in astrocyte density and GFAP expression and area, early in the disease and prior to neuronal loss. Expression of astrocytic core homeostatic genes was also altered in a brain region-specific manner and correlated with neuronal activity, indicating that astrocytes may compensate or exacerbate neuronal dysfunction. Late in disease, expression of astrocytic homeostatic genes was reduced in all four brain regions, indicating loss of astrocyte functions. We observed no obvious correlation between spatiotemporal changes in microglia and spatiotemporal astrocyte alterations, indicating a complex orchestration of glial phenotypes in disease. These results support spatiotemporal diversity of glial phenotypes as an important feature of the brain disease that may contribute to SCA1 pathogenesis in a brain region and disease stage-specific manner.

Are sexual problems more common in women who have had a tubal ligation? A population-based study of Australian women.

OBJECTIVE: To investigate whether women who have had a tubal ligation are more likely to experience sexual problems than other women. DESIGN: Population-based telephone survey. SETTING: Australia-wide, including cities, regional towns, and rural areas. POPULATION: A total of 3448 Australian women aged between 16 and 64 years. METHODS: Women were surveyed using random-digit dialling throughout 2004 and 2005. MAIN OUTCOME MEASURES: Prevalence of sexual problems and ratings of sexual satisfaction, relationship satisfaction, and sexual pleasure. RESULTS: From a weighted sample of 2721 women, 447 (16.4%) reported having had a tubal ligation, with 85.0% currently aged between 40 and 64 years. Having a tubal ligation was not associated with any specific sexual problem, such as physical pain during sex or an inability to reach orgasm. In fact, after controlling for age and other sociodemographic differences, sterilised women were significantly less likely than non-sterilised women to lack an interest in having sex (OR 0.69, 95% CI 0.54-0.89), to take 'too long' to reach orgasm (OR 0.69, 95% CI 0.50-0.96), to experience vaginal dryness during sex (OR 0.70, 95% CI 0.50-0.96), and to find sex unpleasurable (OR 0.64, 95% CI 0.46-0.90). Sterilised women were also more likely to experience extremely high levels of sexual satisfaction (OR 1.66, 95% CI 1.27-2.18), relationship satisfaction (OR 1.29, 95% CI 1.01-1.67), and sexual pleasure (OR 1.59, 95% CI 1.20-2.12). CONCLUSIONS: Our findings suggest no adverse effects, and possibly some benefits, for the sexual lives of women undergoing tubal ligation. These findings should be included with other educational material for couples considering sterilisation as a contraception option.

Rising inability to obtain needed health care among homeless persons in Birmingham, Alabama (1995-2005).

BACKGROUND: Homeless persons depend disproportionately on the health-care safety net for medical services. National reports identify financial strains to this safety net. Whether this has affected homeless persons is unknown. OBJECTIVES: We quantified changes in the proportion of homeless persons reporting unmet need for health care in Birmingham, Alabama, comparing two periods, 1995 and 2005. We assessed whether a period effect was independent of characteristics of persons surveyed. DESIGN: Analysis of two surveys conducted with identical methods among representative samples of homeless persons in 1995 (n = 161) and 2005 (n = 161). MEASUREMENTS: Report of unmet need (inability to obtain care when needed) was the dependent variable. Two survey periods (1995 and 2005) were compared, with multivariable adjustment for sociodemographic and health characteristics. Reasons for unmet need were determined among the subset of persons reporting unmet need. RESULTS: Unmet need for health care was more common in 2005 (54%) than in 1995 (32%) (p < 0.0001), especially for non-Blacks (64%) and females (65%). Adjusting for individual characteristics, a survey year of 2005 independently predicted unmet need (odds ratio 2.68, 95% CI 1.49-4.83). Among persons reporting unmet need (87 of 161 in 2005; 52 of 161 in 1995), financial barriers were more commonly cited in 2005 (67% of 87) than in 1995 (42% of 52) (p = 0.01). CONCLUSION: A rise in unmet health-care needs was reported among Birmingham's homeless from 1995 to 2005. This period effect was independent of population characteristics and may implicate a local safety net inadequacy. Additional data are needed to determine if this represents a national trend.

Cyanovinyl phosphate: a prebiological phosphorylating agent?

Cyanovinyl phosphate may be prepared by the addition reaction of phosphate to cyanoacetylene. Kinetic studies have established that cyanovinyl phosphate undergoes a slow pseudo-first-order hydrolysis in aqueous solution. Cyanovinyl phosphate converts uridine to uridine monophosphate and phosphate to pyrophosphate.

Oligomerization of ribonucleotides on montmorillonite: reaction of the 5'-phosphorimidazolide of adenosine.

The regiospecific formation of oligomers from unblocked monomers in aqueous solution is one of the central tenets in research on the origins of life on earth. Direct experimental support for this hypothesis has been obtained in studies of the condensation of the 5'-phosphorimidazolide of adenosine (ImpA) with itself and with P1,P2-diadenosine-5',5'-pyrophosphate (AppA) in water in the presence of a montmorillonite clay. Oligomers of up to ten nucleotides in length are formed. Analysis of the trimers, tetramers, and pentamers formed from a 9:1 ImpA:AppA mixture has shown that 85% of the bonds formed are 3',5'-linked and that any 2',5'-linkages present are at the phosphodiester bond next to the 3'-terminus of the oligomers.

Conditions for purine synthesis: did prebiotic synthesis occur at low temperatures?

The rate of polymerization of hydrogen cyanide to aminomalononitrile and the tetramer, diaminomalonodinitrile, is quadratic in the total cyanide concentration. Since the reactions form part of a plausible prebiotic purine synthesis and since they compete with hydrolysis, concentration of cyanide may have been important. This may be achieved usefully by cooling to separate out ice.

Chemical evolution from hydrogen cyanide: photochemical decarboxylation of orotic acid and orotate derivatives.

Irradiation of solutions at pH 7 to pH 8.5 of orotic acid, orotidine, and orotidine 5'-phosphate with light at 254 nanometers yields the corresponding uracil derivative via the singlet excited state. This reaction completes a plausible prebiotic synthesis of uracil and its derivatives starting from HCN as the only carbon source.

Biogeography of free-living soil nematodes from the perspective of plate tectonics.

In this first biogeographical synthesis based on the morphology and known distribution of a group of free-living soil nematodes, data indicate a pre-Jurassic origin followed by West Gondwanaland radiation for some genera and Laurasian radiation for others.

Cyanoacetylene in prebiotic synthesis.

Cyanoacetylene is a major nitrogen-containing product of the action of an electric discharge on a mixture of methane and nitrogen. It reacts with simple inorganic substances in aqueous solution to give products including asparticacid, asparagine, and cytosine.

Photochemical reactions and the chemical evolution of purines and nicotinamide derivatives.

The photochemical rearrangement of a tetramer of hydrogen cyanide to 4-aminoimidazole-5-carbonitrile, a critical step in the proposed prebiotic synthesis of purines, proceeds in high yield in the absence of oxygen without photodestruction of the reaction product. The mechanism of the rearrangement involves the conversion of the excited singlet of the hydrogen cyanide tetramer to 2-imino-3-cyano-4-aminoazetine, which then rearranges to the imidazole product. The photolysis of the vinylogous enaminonitrile 1,3-dicyano4-amino-1,3-butadiene yields 6-aminonicotinonitrile. The latter reaction affords an efficient route to a nicotinamide derivative from cyanoacetylene.

Helicon plasma generator-assisted surface conversion ion source for the production of H(-) ion beams at the Los Alamos Neutron Science Center.

The converter-type negative ion source currently employed at the Los Alamos Neutron Science Center (LANSCE) is based on cesium enhanced surface production of H(-) ion beams in a filament-driven discharge. In this kind of an ion source the extracted H(-) beam current is limited by the achievable plasma density which depends primarily on the electron emission current from the filaments. The emission current can be increased by increasing the filament temperature but, unfortunately, this leads not only to shorter filament lifetime but also to an increase in metal evaporation from the filament, which deposits on the H(-) converter surface and degrades its performance. Therefore, we have started an ion source development project focused on replacing these thermionic cathodes (filaments) of the converter source by a helicon plasma generator capable of producing high-density hydrogen plasmas with low electron energy. In our studies which have so far shown that the plasma density of the surface conversion source can be increased significantly by exciting a helicon wave in the plasma, and we expect to improve the performance of the surface converter H(-) ion source in terms of beam brightness and time between services. The design of this new source and preliminary results are presented, along with a discussion of physical processes relevant for H(-) ion beam production with this novel design. Ultimately, we perceive this approach as an interim step towards our long-term goal, combining a helicon plasma generator with an SNS-type main discharge chamber, which will allow us to individually optimize the plasma properties of the plasma cathode (helicon) and H(-) production (main discharge) in order to further improve the brightness of extracted H(-) ion beams.

Neuronal Gonadotrophin-Releasing Hormone (GnRH) and Astrocytic Gonadotrophin Inhibitory Hormone (GnIH) Immunoreactivity in the Adult Rat Hippocampus.

Gonadotrophin-releasing hormone (GnRH) and gonadotrophin inhibitory hormone (GnIH) are neuropeptides secreted by the hypothalamus that regulate reproduction. GnRH receptors are not only present in the anterior pituitary, but also are abundantly expressed in the hippocampus of rats, suggesting that GnRH regulates hippocampal function. GnIH inhibits pituitary gonadotrophin secretion and is also expressed in the hippocampus of a songbird; its role outside of the reproductive axis is not well established. In the present study, we employed immunohistochemistry to examine three forms of GnRH [mammalian GnRH-I (mGnRH-I), chicken GnRH-II (cGnRH-II) and lamprey GnRH-III (lGnRH-III)] and GnIH in the adult rat hippocampus. No mGnRH-I and cGnRH-II+ cell bodies were present in the hippocampus. Sparse mGnRH-I and cGnRH-II+ fibres were present within the CA1 and CA3 fields of the hippocampus, along the hippocampal fissure, and within the hilus of the dentate gyrus. No lGnRH-III was present in the rodent hippocampus. GnIH-immunoreactivity was present in the hippocampus in cell bodies that resembled astrocytes. Males had more GnIH+ cells in the hilus of the dentate gyrus than females. To confirm the GnIH+ cell body phenotype, we performed double-label immunofluorescence against GnIH, glial fibrillary acidic protein (GFAP) and NeuN. Immunofluorescence revealed that all GnIH+ cell bodies in the hippocampus also contained GFAP, a marker of astrocytes. Taken together, these data suggest that GnRH does not reach GnRH receptors in the rat hippocampus primarily via synaptic release. By contrast, GnIH might be synthesised locally in the rat hippocampus by astrocytes. These data shed light on the sites of action and possible functions of GnRH and GnIH outside of the hypothalamic-pituitary-gonadal axis.

Magnetic resonance imaging. Diverse appearances of uveal malignant melanomas.

Fifteen patients with uveal malignant melanomas were studied by magnetic resonance imaging. The magnetic resonance imaging appearances varied from those that have been reported previously to be characteristic of these tumors. In our series, malignant melanomas were of high signal on the T1 sequence and of variable but usually also of high signal on the T2 and Short Tau Inversion Recovery (STIR) sequences, a signal combination rarely described before. We postulate that magnetic resonance imaging appearances may be dependent on variations in histologic factors and on the type and field strength of the scanner used. It is widely believed that the paramagnetic melanin in malignant melanomas gives these tumors characteristic magnetic resonance imaging appearances, but our finding of diverse magnetic resonance imaging appearances for proved malignant melanomas suggests that this may not always be the case. We advise caution in diagnosing malignant melanomas from magnetic resonance imaging appearances alone.