Environmental and sociodemographic factors associated with zoonotic pathogen occurrence in Norway rats (Rattus norvegicus) from Windsor, Ontario

AIMS

Rat-associated zoonotic pathogen transmission at the human-wildlife interface is a public health concern in urban environments where Norway rats (Rattus norvegicus) thrive on abundant anthropogenic resources and live in close contact with humans and other animal species. To identify potential factors influencing zoonotic pathogen occurrence in rats, we investigated associations between environmental and sociodemographic factors and Leptospira interrogans and Bartonella spp. infections in rats from Windsor, Ontario, Canada, while controlling for the potential confounding effects of animal characteristics (i.e., sexual maturity and body condition).

METHODS AND RESULTS

Between November 2018 and June 2021, 252 rats were submitted by collaborating pest control professionals. Kidney and spleen samples were collected for L. interrogans and Bartonella spp. PCR and sequencing, respectively. Of the rats tested by PCR, 12.7% (32/252) were positive for L. interrogans and 16.3% (37/227) were positive for Bartonella species. Associations between infection status and environmental and sociodemographic variables of interest were assessed via mixed multivariable logistic regression models with a random intercept for social group and fixed effects to control for sexual maturity and body condition in each model. The odds of L. interrogans infection were significantly higher in rats from areas with high building density (odds ratio [OR]: 3.76; 95% CI: 1.31-10.79; p = 0.014), high human population density (OR: 3.31; 95% CI: 1.20-9.11; p = 0.021), high proportion of buildings built in 1960 or before (OR: 11.21; 95% CI: 2.06-60.89; p = 0.005), and a moderate number of reports of uncollected garbage compared to a low number of reports (OR: 4.88; 95% CI: 1.01-23.63; p = 0.049). A negative association was observed between median household income and Bartonella spp. infection in rats (OR: 0.26; 95% CI: 0.08-0.89; p = 0.031).

CONCLUSIONS

Due to the complexity of the ecology of rat-associated zoonoses, consideration of environmental and sociodemographic factors is of critical importance to better understand the nuances of host-pathogen systems and inform how urban rat surveillance and intervention efforts should be distributed within cities.

Rat Hepatitis E Virus in Norway Rats, Ontario, Canada, 2018-2021

We tested liver samples from 372 Norway rats (Rattus norvegicus) from southern Ontario, Canada, during 2018-2021 to investigate presence of hepatitis E virus infection. Overall, 21 (5.6%) rats tested positive for the virus. Sequence analysis demonstrated all infections to be rat hepatitis E virus (Rocahepevirus ratti genotype C1).

OC-026 PERFORMING A SLIT ON THE MESH TO ENCIRCLE THE CORD STRUCTURES DURING LAPAROSCOPIC INGUINAL HERNIA REPAIR - A SYSTEMATIC REVIEW AND META-ANALYSIS

Aim

There are several modifications in the technique for the placement of mesh during laparoscopic inguinal hernia repair. The present study aimed to provide stronger evidence in establishing whether the slit mesh technique is superior to the non-slit technique (the most common practice). The primary outcome was recurrence and secondary outcomes were postoperative groin pain, bleeding, seroma formation and duration of surgery.

Material & Methods

Eligible studies had to compare the two methods of mesh placement slit Vs non slit in laparoscopic TEP or TAPP inguinal hernia repair. Databases searched were Embase, Medline, Cochrane collaboration, NICE guidelines search.

The meta-analysis was conducted using Review Manager software 5:4. The outcomes were expressed in odd ratios with their 95% confidence intervals. Where significant heterogeneity existed (I2>75%) a random effects model was used otherwise a fixed effects model was used.

Results

Five studies included, all were single centre studies, 4 retrospective and one prospective observational studies. 1076 patients included, 633 in the slit group and 434 in the non-slit group. The male to female ration was 9:1.

There were 10 (1.5%) recurrences in the slit group compared to 12 (2.5%) in the non-slit group 0.62, 95% CI (0.27–1.41). There was no difference in the incidence of post-operative bleeding (1.21, 95%CI 0.4–3.66), seroma formation (1.5, 95% CI 0.81–2.76), or post-operative neuralgia (0.98, 95%CI 0.11–8.92).

Conclusion

There is no advantage in performing a slit on the mesh to encircle the cord structures during laparoscopic inguinal hernia repair.

Engineered Cytochrome P450-Catalyzed Oxidative Biaryl Coupling Reaction Provides a Scalable Entry into Arylomycin Antibiotics

We report herein the first example of a cytochrome P450-catalyzed oxidative carbon-carbon coupling process for a scalable entry into arylomycin antibiotic cores. Starting from wild-type hydroxylating cytochrome P450 enzymes and engineered Escherichia coli, a combination of enzyme engineering, random mutagenesis, and optimization of reaction conditions generated a P450 variant that affords the desired arylomycin core 2d in 84% assay yield. Furthermore, this process was demonstrated as a viable route for the production of the arylomycin antibiotic core on the gram scale. Finally, this new entry affords a viable, scalable, and practical route for the synthesis of novel Gram-negative antibiotics.

Incorporating NOE-Derived Distances in Conformer Generation of Cyclic Peptides with Distance Geometry

Nuclear magnetic resonance (NMR) data from NOESY (nuclear Overhauser enhancement spectroscopy) and ROESY (rotating frame Overhauser enhancement spectroscopy) experiments can easily be combined with distance geometry (DG) based conformer generators by modifying the molecular distance bounds matrix. In this work, we extend the modern DG based conformer generator ETKDG, which has been shown to reproduce experimental crystal structures from small molecules to large macrocycles well, to include NOE-derived interproton distances. In noeETKDG, the experimentally derived interproton distances are incorporated into the distance bounds matrix as loose upper (or lower) bounds to generate large conformer sets. Various subselection techniques can subsequently be applied to yield a conformer bundle that best reproduces the NOE data. The approach is benchmarked using a set of 24 (mostly) cyclic peptides for which NOE-derived distances as well as reference solution structures obtained by other software are available. With respect to other packages currently available, the advantages of noeETKDG are its speed and that no prior force-field parametrization is required, which is especially useful for peptides with unnatural amino acids. The resulting conformer bundles can be further processed with the use of structural refinement techniques to improve the modeling of the intramolecular nonbonded interactions. The noeETKDG code is released as a fully open-source software package available at www.github.com/rinikerlab/customETKDG.

Stereocontrolled Synthesis of Arylomycin-Based Gram-Negative Antibiotic GDC-5338

We report herein an efficient, stereocontrolled, and chromatography-free synthesis of the novel broad spectrum antibiotic GDC-5338. The route features the construction of a functionalized tripeptide backbone, a high-yielding macrocyclization via a Pd-catalyzed Suzuki-Miyaura reaction, and the late-stage elaboration of key amide bonds with minimal stereochemical erosion. Through extensive reaction development and analytical understanding, these key advancements allowed the preparation of GDC-5338 in 17 steps, 15% overall yield, >99 A % HPLC, and >99:1 dr.

The transcriptional landscape of polyploid wheat

The coordinated expression of highly related homoeologous genes in polyploid species underlies the phenotypes of many of the world's major crops. Here we combine extensive gene expression datasets to produce a comprehensive, genome-wide analysis of homoeolog expression patterns in hexaploid bread wheat. Bias in homoeolog expression varies between tissues, with ~30% of wheat homoeologs showing nonbalanced expression. We found expression asymmetries along wheat chromosomes, with homoeologs showing the largest inter-tissue, inter-cultivar, and coding sequence variation, most often located in high-recombination distal ends of chromosomes. These transcriptionally dynamic genes potentially represent the first steps toward neo- or subfunctionalization of wheat homoeologs. Coexpression networks reveal extensive coordination of homoeologs throughout development and, alongside a detailed expression atlas, provide a framework to target candidate genes underpinning agronomic traits in wheat.

Characterizing the in vitro species differences in N-glucuronidation of a potent pan-PIM inhibitor GNE-924 containing a 3,5-substituted 6-azaindazole

1. Glucuronidation of amines has been shown to exhibit large species differences, where the activity is typically more pronounced in human than in many preclinical species such as rat, mouse, dog and monkey. The purpose of this work was to characterize the in vitro glucuronidation of GNE-924, a potent pan-PIM inhibitor, to form M1 using liver microsomes (LM) and intestinal microsomes (IM). 2. M1 formation kinetics varied highly across species and between liver and intestinal microsomes. In LM incubations, rat exhibited the highest rate of M1 formation (CL_int,app) at 140 ± 10 µL/min/mg protein, which was approximately 30-fold higher than human. In IM incubations, mouse exhibited the highest CL_int,app at 484 ± 40 µL/min/mg protein, which was >1000-fold higher than human. In addition, CL_int,app in LM was markedly higher than IM in human and monkey. In contrast, CL_int,app in IM was markedly higher than LM in dog and mouse. 3. Reaction phenotyping indicated that UGT1A1, UGT1A3, UGT1A9, UGT2B4 and the intestine-specific UGT1A10 contributed to the formation of M1. 4. This is one of the first reports showing that N-glucuronidation activity is significantly greater in multiple preclinical species than in humans, and suggests that extensive intestinal N-glucuronidation may limit the oral exposure of GNE-924.

Superior mesenteric artery syndrome: a single centre experience of laparoscopic duodenojejunostomy as the operation of choice

INTRODUCTION The superior mesenteric artery (SMA) syndrome, or Wilkie's syndrome, is a rare cause of postprandial epigastric pain, vomiting and weight loss caused by compression of the third part of the duodenum as it passes beneath the proximal superior mesenteric artery. The syndrome may be precipitated by sudden weight loss secondary to other pathologies, such as trauma, malignancy or eating disorders. Diagnosis is confirmed by angiography, which reveals a reduced aorto-SMA angle and distance, and contrast studies showing duodenal obstruction. Conservative management aims to increase intra-abdominal fat by dietary manipulation and thereby increase the angle between the SMA and aorta. Where surgery is indicated, division of the ligament of Treitz, anterior transposition of the third part of the duodenum and duodenojejunostomy have been described. METHODS We present four cases of SMA syndrome where the intention of treatment was laparoscopic duodenojejunostomy. The procedure was completed successfully in three patients, who recovered quickly with no short-term complications. A fourth patient underwent open gastrojejunostomy (complicated by an anastomotic bleed) when dense adhesions prevented duodenojejunostomy. CONCLUSIONS The superior mesenteric artery syndrome should be considered in patients with epigastric pain, prolonged vomiting and weight loss. Laparoscopic duodenojejunostomy is a safe and effective operation for management of the syndrome. A multi-speciality team approach including gastrointestinal, vascular and radiological specialists should be invoked in the management of these patients.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Gallbladder agenesis

This case report describes unusual congenital biliary anatomy encountered at a routine laparoscopic cholecystectomy. Imaging obtained prior to surgery (ultrasonography and magnetic resonance cholangiopancreatography) had been misleading. The case highlights the importance of careful dissection even with anticipated normal anatomy.

The Use of TOC Reconciliation as a Means of Establishing the Degree to Which Chromatographic Screening of Plastic Material Extracts for Organic Extractables Is Complete

Extracts of plastic packaging, manufacturing, and delivery systems (or their materials of construction) are analyzed by chromatographic methods to establish the system's extractables profile. The testing strategy consists of multiple orthogonal chromatographic methods, for example, gas and liquid chromatography with multiple detection strategies. Although this orthogonal testing strategy is comprehensive, it is not necessarily complete and members of the extractables profile can elude detection and/or accurate identification/quantification. Because the chromatographic methods rarely indicate that some extractables have been missed, another means of assessing the completeness of the profiling activity must be established. If the extracts are aqueous and contain no organic additives (e.g., pH buffers), then they can be analyzed for their total organic carbon content (TOC). Additionally, the TOC of an extract can be calculated based on the extractables revealed by the screening analyses. The measured and calculated TOC can be reconciled to establish the completeness and accuracy of the extractables profile. If the reconciliation is poor, then the profile is either incomplete or inaccurate and additional testing is needed to establish the complete and accurate profile. Ten test materials and components of systems were extracted and their extracts characterized for organic extractables using typical screening procedures. Measured and calculated TOC was reconciled to establish the completeness of the revealed extractables profile. When the TOC reconciliation was incomplete, the profiling was augmented with additional analytical testing to reveal the missing members of the organic extractables profile. This process is illustrated via two case studies involving aqueous extracts of sterile filters.

LAY ABSTRACT

Plastic materials and systems used to manufacture, contain, store, and deliver pharmaceutical products are extracted and the extracts analyzed to establish the materials' (or systems') organic extractables profile. Such testing typically consists of multiple chromatographic approaches whose differences help to ensure that all organic extractables are revealed, measured, and identified. Nevertheless, this rigorous screening process is not infallible and certain organic extractables may elude detection. If the extraction medium is aqueous, the process of total organic carbon (TOC) reconciliation is proposed as a means of establishing when some organic extractables elude detection. In the reconciliation, the TOC of the extracts is both directly measured and calculated from the chromatographic data. The measured and calculated TOC is compared (or reconciled), and the degree of reconciliation is an indication of the completeness and accuracy of the organic extractables profiling. If the reconciliation is poor, then the extractables profile is either incomplete or inaccurate and additional testing must be performed to establish the complete and accurate profile. This article demonstrates the TOC reconciliation process by considering aqueous extracts of 10 different test articles. Incomplete reconciliations were augmented with additional testing to produce a more complete TOC reconciliation.

'Time critical' rapid amputation using fire service hydraulic cutting equipment

INTRODUCTION

Entrapped trauma victims require extrication, which, on rare occasions, may involve amputation of a limb. Standard extrication techniques sometimes fail or may be impossible, leading to the death of the entrapped victim. We propose that the use of fire service hydraulic cutting equipment can be used effectively to urgently amputate a limb, where conventional techniques are unusable.

METHOD

The study aims to determine: (i) the potential use of this equipment to achieve expeditious life-saving amputations and (ii) the effect the fire service hydraulic cutting equipment has on the bony and surrounding soft tissues. Initially a porcine limb was used followed by fresh-frozen cadaveric lower limbs. We recorded the time, number of cuts, proximal fracture propagation and quality of bone cut when performing amputations at five levels.

RESULTS

The experiment confirms that faster guillotine amputations in human cadaveric lower limb specimens can be achieved by using fire service hydraulic cutting equipment. Overall, the average time to complete an amputation in these ideal experimental circumstances at all five levels was quicker using the hydraulic cutting equipment. Either one or two cutting actions were required to achieve the amputation using fire service hydraulic cutting equipment. The degree and proximal extent of the comminution were greater using the fire service hydraulic cutting equipment.

CONCLUSION

If circumstances and time constrains allow, a conventional amputation technique carried out by a trained medical practitioner would be preferable to the use of the fire service hydraulic cutting equipment. However, we feel that this technique could be used to perform emergent amputation under trained medical supervision, if it is felt that a standard amputation technique would take too long or the environment is too restrictive to perform a standard amputation safely.

A proteomic survey of nonribosomal peptide and polyketide biosynthesis in actinobacteria

Actinobacteria such as streptomycetes are renowned for their ability to produce bioactive natural products including nonribosomal peptides (NRPs) and polyketides (PKs). The advent of genome sequencing has revealed an even larger genetic repertoire for secondary metabolism with most of the small molecule products of these gene clusters still unknown. Here, we employed a "protein-first" method called PrISM (Proteomic Investigation of Secondary Metabolism) to screen 26 unsequenced actinomycetes using mass spectrometry-based proteomics for the targeted detection of expressed nonribosomal peptide synthetases or polyketide synthases. Improvements to the original PrISM screening approach (Nat. Biotechnol. 2009, 27, 951-956), for example, improved de novo peptide sequencing, have enabled the discovery of 10 NRPS/PKS gene clusters from 6 strains. Taking advantage of the concurrence of biosynthetic enzymes and the secondary metabolites they generate, two natural products were associated with their previously "orphan" gene clusters. This work has demonstrated the feasibility of a proteomics-based strategy for use in screening for NRP/PK production in actinomycetes (often >8 Mbp, high GC genomes) versus the bacilli (2-4 Mbp genomes) used previously.

Proteomics-based discovery of koranimine, a cyclic imine natural product

Nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs) are large enzymes responsible for the biosynthesis of medically and ecologically important secondary metabolites. In a previous report, we described a proteomics approach to screen for expressed NRPSs or PKSs from bacteria with or without sequenced genomes. Here we used this proteome mining approach to discover a novel natural product arising from rare adenylation (A) and reductase (Red) domains in its biosynthetic machinery. We also cloned the entire gene cluster and elucidated the biosynthesis of the new compound, which is produced by an unsequenced Bacillus sp. isolated from soil collected in Koran, Louisiana.

Biostructural features of additional jasplakinolide (jaspamide) analogues

The cyclodepsipeptide jasplakinolide (1) (aka jaspamide), isolated previously from the marine sponge Jaspis splendens, is a unique cytotoxin and molecular probe that operates through stabilization of filamentous actin (F-actin). We have recently disclosed that two analogues of 1, jasplakinolides B (3) and E, were referred to the National Cancer Institute's (NCI) Biological Evaluation Committee, and the objective of this study was to reinvestigate a Fijian collection of J. splendens in an effort to find jasplakinolide congeners with similar biological properties. The current efforts have afforded six known jasplakinolide analogues (4-7, 9, 10), two structures requiring revision (8 and 14), and four new congeners of 1 (11-13, 15) including open-chain derivatives and structures with modified β-tyrosine residues. Compounds were evaluated for biological activity in the NCI's 60 cell line screen and in a microfilament disruption assay in both HCT-116 and HeLa cells. These two phenotypic screens provide evidence that each cytotoxic analogue, including jasplakinolide B (3), operates by modification of microfilaments. The new structure jasplakinolide V (13) has also been selected for study by the NCI's Biological Evaluation Committee. In addition, the results of a clonogenic dose-response study on jasplakinolide are presented.

New structures and bioactivity properties of jasplakinolide (jaspamide) analogues from marine sponges

The goal of this study was to isolate and study additional jasplakinolide analogues from two taxonomically distinct marine sponges including two Auletta spp. and one Jaspis splendens. This led to the isolation of jasplakinolide (1) and eleven jasplakinolide analogues (3-13) including seven new analogues (6-10, 12, and 13). Structure elucidation of the new compounds was based on a combination of 1D and 2D NMR analysis, optical rotation, circular dichroism, and preparation of Mosher's esters. Five of the new compounds are oxidized tryptophan derivatives of 1, including a unique quinazoline derivative (9). Compounds 1, 3, 5-8, and 11 were evaluated in the NCI 60 cell line screen, and all compounds were tested in a microfilament disruption assay. Jasplakinolide B (11) exhibited potent cytotoxicity (GI(50) < 1 nM vs human colorectal adenocarcinoma (HCT-116) cells) but did not exhibit microfilament-disrupting activity at 80 nM.

Polyketide assembly lines of uncultivated sponge symbionts from structure-based gene targeting

There is increasing evidence that uncultivated bacterial symbionts are the true producers of numerous bioactive compounds isolated from marine sponges. The localization and heterologous expression of biosynthetic genes could clarify this issue and provide sustainable supplies for a wide range of pharmaceuticals. However, identification of genes in the usually highly complex symbiont communities remains a challenging task. For polyketides, one of the most important groups of sponge-derived drug candidates, we have developed a general strategy that allows one to rapidly access biosynthetic gene clusters based on chemical moieties. Using this method, we targeted polyketide synthase genes from two different sponge metagenomes. We have obtained from a sponge-bacterial association a complete pathway for the rare and potent antitumor agent psymberin from Psammocinia aff. bulbosa. The data support the symbiont hypothesis and provide insights into natural product evolution in previously inaccessible bacteria.

Using enzyme assays to evaluate the structure and bioactivity of sponge-derived meroterpenes

Enzyme screening of crude sponge extracts prioritized a 2005 Papua New Guinea collection of Hyrtios sp. for further study. The MeOH extract contained puupehenone and four puupehenone analogues (1, 2, 3, 5, and 7) along with a new diastereomer, 20-epi-hydroxyhaterumadienone (4), and a new analogue, 15-oxo-puupehenoic acid (6). The drimane terpene core of 4 and 6 was rapidly dereplicated, and the modified Mosher's method identified 4, while 1D and 2D NMR techniques were used to solve 6. These compounds plus noteworthy repository natural products and standards were tested against three lipoxygenase isozymes, human 5-, 12-, and 15-lipoxygenases. Significant potency and selectivity profiles were exhibited in the human 5-lipoxygenase assay by puupehenone (1) and jaspaquinol (9) and structural factors responsible for activity identified.

Building research capacity for evidence-informed tobacco control in Canada: a case description

Tobacco use remains the leading cause of death and disability in Canada. Insufficient research capacity can inhibit evidence-informed decision making for tobacco control. This paper outlines a Canadian project to build research capacity, defined as a community's ability to produce research that adequately informs practice, policy, and future research in a timely, practical manner. A key component is that individuals and teams within the community must mutually engage around common, collectively negotiated goals to address specific practices, policies or programs of research. An organizing framework, a set of activities to build strategic recruitment, productivity tools, and procedures for enhancing social capital are described. Actions are intended to facilitate better alignment between research and the priorities of policy developers and service providers, enhance the external validity of the work performed, and reduce the time required to inform policy and practice.

Revisiting the sponge sources, stereostructure, and biological activity of cyclocinamide a

The dramatic biogeographical variations in the secondary metabolites from Psammocinia aff. bulbosa have complicated our efforts to reisolate the two most cytotoxic of its metabolites, (+)-psymberin and (+)-cyclocinamide A. Reported now are the results of a new study that demonstrates our ability to repeatedly isolate these two compounds through targeted collection efforts. Additional study of the new sample of (+)-cyclocinamide A has enabled finalizing its biological activity and absolute stereochemistry as 4S, 7S, 11S, 14S.

The effects of exposure to an acute naturalistic stressor on working memory, state anxiety and salivary cortisol concentrations

Exposure to an acute naturalistic stressor induces both psychological and physiological changes in humans. The two studies reported here explored the impact of exposure to an acute naturalistic stressor on state anxiety, working memory and HPA axis activation (salivary cortisol). In both experiments, ten healthy male participants were exposed to an acute naturalistic stressor, helicopter underwater evacuation training (HUET), and their physiological and behavioural responses before (first study) and after (second study) the stressor were compared to ten non-stressed controls. The results of both experiments showed that working memory performance was preserved during anticipation of an acute stressor, but impairments were observed immediately after stress exposure. Participants reported significantly higher state anxiety levels during anticipation and following stress exposure, whereas significant elevations in cortisol levels were only observed 25 min post exposure to stress, but not before or immediately after stress exposure. The results of both experiments demonstrated a dissociation between behavioural and biochemical measures and provided evidence for a dissociation of the effects of stress on cognitive and physiological measures depending on the time of testing, with cognitive impairments most evident following stress exposure.

Pediatric healthcare quality: A novel approach to lifelong child health research

Medical science historically focuses on biomedical research about causes and treatment of disease. McMaster Child Health Research Institute (MCHRI), in Hamilton, Ontario, Canada, takes a different approach to research about lifelong health in children with varied chronic conditions. Staff at MCHRI propose to develop research programs to help "children with complicated lives and their families" meet the challenges of growing up in the face of threats to their health and development in order to help both children and families reach their full potential. This "noncategorical approach" to health services research is timely for addressing chronic childhood illnesses and disabilities across the life span.

Probing the bioactive constituents from chemotypes of the sponge Psammocinia aff. bulbosa

Since the report of (+)-psymberin (2) in 2004, many synthetic groups have pursued the synthesis of this compound, and our group has further collected Psammocinia aff. bulbosa to successfully isolate more 2. With more (+)-psymberin (2) in hand, additional clonogenic studies, a therapeutic efficacy assessment, and the hollow fiber assay have been completed. The inconsistent production of (+)-psymberin (2) and the classification of six Psammocinia species are further discussed herein. The most recent of these six collections resulted in the isolation of a new brominated cyclic peptide, (-)-psymbamide A (4), which is the first report of a Psammocinia-derived compound in this peptide class. The planar structure was solved via dereplication with Marinlit, HRESIMS, and 1D and 2D NMR techniques, and the absolute configuration determined using Marfey's method.

Comparison of fascaplysin and related alkaloids: a study of structures, cytotoxicities, and sources

The fascaplysin class of compounds have been further investigated from six organisms consisting of four sponge collections (Fascaplysinopsis reticulata) and two tunicate collections (Didemnum sp.). This work is an extension of an earlier communication and reports the isolation of 12 new fascaplysin derivatives: 10-bromofascaplysin (7), 3,10-dibromofascaplysin (8), homofascaplysate A (9), homofascaplysin B-1 (11), 3-bromohomofascaplysins B (12), B-1 (13), and C (15), 7,14-dibromoreticulatine (17), reticulatol (20), 14-bromoreticulatol (21), and 3-bromosecofascaplysins A (22) and B (23), along with known compounds: fascaplysin (1), reticulatine (4), 3-bromofascaplysin (6), and homofascaplysin C (14). Selected compounds were screened in a cell-based cytotoxicity assay with compounds 1, 6, and fascaplysin A (24) also screened in the NCI 60 cell line panel. A biogenetic pathway for the brominated fascaplysins and brominated related alkaloids is proposed and discussed.

2nd to 4th digit ratio and a universal mean for prenatal testosterone in homosexual men

Male homosexuals are said to have experienced high prenatal testosterone, and testosterone may have deleterious effects on the immune system. The question of the prenatal androgen status of male homosexuals is therefore of importance. There is evidence that the relative length of the 2nd and 4th digit (2D:4D) is negatively correlated with prenatal testosterone. We review the available literature, and provide further data on 2D:4D in male heterosexuals and homosexuals. Normative values of male mean 2D:4D ratio vary between 0.94 to 1.00 across populations. However, mean 2D:4D ratio is relatively constant among male homosexuals from different populations, with a mean of 0.96 to 0.97. Therefore homosexuals appear to be more androgenised (lower 2D:4D) than heterosexuals in some populations, while in others they appear to be less androgenised (higher 2D:4D) than heterosexuals. Speculations regarding the effect of early sex steroids on the health of male homosexuals should therefore focus on the effects of prenatal testosterone levels associated with 2D:4D ratios of between 0.96 and 0.97.

What causes inefficient transmission of male-killing Wolbachia in Drosophila?

Selfish genetic elements that distort the sex ratio are common in arthropods. Theory predicts they will invade and spread to fixation if they are vertically transmitted with perfect fidelity, potentially leading to host extinction. For inherited microorganisms that distort the sex ratio, inefficient vertical transmission or incomplete sex ratio distorting ability is required for host persistence. However, the relative roles of genetic and environmental factors in permitting the survival of male hosts and preventing parasite transmission are poorly understood. We examined the causes of transmission infidelity and male survival for a male-killing Wolbachia strain in Drosophila bifasciata. Under standard laboratory conditions (18 degrees C), in its standard genetic background, males are produced very rarely, and no case of reversion has been observed in 20 generations of laboratory rearing. To investigate the role of host genetic factors, Wolbachia was crossed into 27 different inbred lines of D. bifasciata, but in no case was reversion observed at preferred environmental temperatures. The role of elevated temperature in inducing inefficient transmission was examined. Whilst vertical transmission was perfect over three generations of maintenance at 23.5 degrees, transmission infidelity was observed at 25 degrees. We conclude that there is no evidence for the presence of either fixed or polymorphic host genes that repress transmission at standard environmental temperatures. However, severe temperature treatment does make vertical transmission imperfect. We suggest that the case of Wolbachia in D. bifasciata is one that is naturally balanced, the population being maintained polymorphic without the evolution of host resistance genes.

Stress distribution in the single-unit osseointegrated dental implant: finite element analyses of axial and off-axial loading

Occlusal overload may contribute to the extensive crestal bone loss often noted around late-failure dental implants. A particularly high risk of traumatic overload occurs with the posterior single-unit implant restoration because the restoration itself is usually wider than the implant, creating the potential for a cantilever effect with high bending moments. The objective of this study was to evaluate the simulated effects of axial and off-axial vertical loads on stress gradients at the implant/bone interface of a single-unit osseointegrated root-form endosseous dental implant. A two-dimensional finite element model was generated. A 490-N load was applied at 0, 2, 4, and 6 mm from the vertical axis of the implant. Off-axis loading resulted in greatly increased compressive stresses within the crestal cortical bone on the side to which the load was applied and similarly increased tensile stresses on the side opposite the load. These stresses increased considerably with each mm increase off axis of the applied load. These data suggest that off-axis loading of single-unit implant restorations provides a significant contribution to increased stresses at the implant/cortical bone interface. The distance off axis at which the load is applied is also significant.

Starvation resistance and adult body composition in a latitudinal cline of Drosophila melanogaster

Latitudinal geographic variation in Drosophila melanogaster is pervasive. Parallel clines in traits such as body size, egg size, ovariole number, and development time have been found on several continents throughout the world. However, a cline in starvation resistance and fat content in D. melanogaster has so far been found only in India. Here we investigate starvation resistance and fat content in 10 populations from South America, in which clines in body size, egg size, and development time have previously been found. We find no evidence for a cline in starvation resistance or fat content in South America. We therefore suggest that the cline in starvation resistance in India may have evolved in response to specific climatic variation found only in India.

The ratio of 2nd to 4th digit length and male homosexuality

Sexual orientation may be influenced by prenatal levels of testosterone and oestrogen. There is evidence that the ratio of the length of 2nd and 4th digits (2D:4D) is negatively related to prenatal testosterone and positively to oestrogen. We report that (a) 2D:4D was lower in a sample of 88 homosexual men than in 88 sex- and age-matched controls recruited without regard to sexual orientation, (b) within the homosexual sample, there was a significant positive relationship between mean 2D:4D ratio and exclusive homosexuality, (c) overall, there was a decrease in 2D:4D from controls to homosexual men to bisexual men and (d) fraternal birth order, a positive predictor of male homosexuality, was not associated with 2D:4D in a sample of 240 Caucasian men recruited without regard to sexual orientation and 45 homosexual men.Further work is needed to confirm the relationships between 2D:4D and sexual orientation. However, these and other recent data tend to support an association between male homosexuality and high fetal testosterone. Very high testosterone levels may be associated with a sexual preference for both men and women.

Modulation of oviductal transport in mares by local application of prostaglandin E2

Equine embryos enter the uterus 144-156 h after ovulation, before which time the passage of embryos through the oviduct is halted in the region of the ampullary-isthmic junction. It is thought that further onward movement of embryos to the uterus is facilitated by secretion of prostaglandin E2 (PGE2) by the embryos, which relaxes the smooth muscle of the isthmus. In the present study, the effect of a single local application of PGE2 on oviductal transport was examined in 22 Thoroughbred and Pony mares that were inseminated on alternate days during oestrus. On day 4 after ovulation, the ipsilateral ovary, oviduct and tip of the uterine horn were visualized by flank laparoscopy, and either a commercial preparation of PGE2 suspended in a triacetin-based gel or a control gel containing no PGE2 was dripped along the external surface of the oviduct. On day 5, the uterus of each mare was flushed three times with phosphate-buffered saline containing 1% (v/v) fetal bovine serum and, if no embryo was recovered, the flushing procedure was repeated on day 7 or 8. Overall, the embryo recovery rate was similar in PGE2-treated and control mares (65 and 63%, respectively). However, the recovery rate of embryos on day 5 was significantly higher for PGE2-treated mares than for control mares (60 versus 0%; P < 0.01), indicating an increased rate of embryo transport in PGE2-treated mares. Furthermore, unfertilized oocytes were recovered from nine of the PGE2-treated mares on day 5 but from none of the control mares. All of the embryos recovered on day 5 were compacted morulae, whereas all of those recovered on days 7 or 8 were expanding blastocysts. The results of the present study support the role of embryonic PGE2 in oviductal transport in mares. The results also demonstrate that a single local application of PGE2 is a simple and practical method for speeding the passage of embryos through the oviduct for nonsurgical recovery of morulae from the uterus.

Agape and moral meaning in pastoral counseling

Argues that the essential key in authentically understanding pastoral counseling and moral meaning is the experience and concept of agape. Details four aspects of agape and illustrates them via clinical examples taken from survivors of childhood sexual abuse.

GRID and Multiphonon States

The development of the GRID technique for determining nuclear level lifetimes of excited low-spin states populated in thermal neutron capture reactions has resulted in the ability to perform detailed studies of proposed multiphonon excitations for the first time. This paper discusses the experimental evidence for multiphonon excitations determined using the GRID technique. In deformed nuclei several good examples of γγK(π) = 4(+) excitations have been established, whereas the experimental evidence gathered on K(π)= 0(+) bands is contradictory, and any interpretations will likely involve the mixing of several different configurations. In vibrational nuclei the GRID technique has helped to establish the existence of multiple quadrupole phonon excitations in (114)Cd, and an almost complete set of quadrupole-octupole coupled states in (144)Nd.

Body composition of preterm infants during infancy

AIMS

To examine body composition in preterm infants.

METHODS

Body composition was measured by dual energy x-ray absorptiometry (DEXA) at hospital discharge, term, 12 weeks, and at 6 and 12 months corrected age in 125 infants (birthweight < or = 1750 g, gestational age < or = 34 weeks).

RESULTS

Body weight derived by DEXA accurately predicted that determined by conventional scales. In both sexes lean mass (LM), fat mass (FM), %FM, bone area (BA), bone mineral mass (BMM), and bone mineral density (BMD) increased rapidly during the study; significant changes were detectable between discharge and term. At 12 months, LM, BA, and BMM, but not FM, %FM, or BMD were greater in boys than in girls. Corrected for age, LM was less than those of the reference term infant; FM and %FM were similar; BMM was greater. Corrected for weight, LM was similar to those of the reference infant, while the FM and %FM of study infants were slightly greater.

CONCLUSIONS

DEXA accurately measures body mass. Body composition in preterm boys and girls differs. Interpretation of DEXA values may depend on whether age or body weight are regarded as the appropriate reference.

In vitro evaluation of the Thermafil technique with and without gutta percha coating

To determine the sealing ability of the Thermafil technique with and without gutta percha on the plastic carrier, 40 maxillary incisors were divided into four treatment groups: (A) Thermafil with gutta percha on the carrier; (B) Thermafil without gutta percha on the carrier; (C) lateral condensation with standardize gutta percha; and (D) a single standardized gutta percha cone. Average leakage in groups A-D were 0.64 mm, 1.32 mm, 0.53 mm, and 0.72 mm, respectively. The only significant difference was between the Thermafil without gutta percha and the other three groups (p < 0.05).

Feeding preterm infants after hospital discharge: effect of dietary manipulation on nutrient intake and growth

The objective of this study was to compare formula intake, the time of weaning, and growth in preterm infants (< or = 1750-g birth weight, < or = 34-wk gestation) fed a standard term or preterm infant formula after initial hospital discharge. Infants were randomized at hospital discharge to be fed a preterm infant formula from discharge to 6 mo corrected age (group A), a term formula from discharge to 6 mo (group B), or the preterm formula (discharge to term) and the term formula (term to 6 mo (group C). Infants were seen biweekly (discharge to term) and monthly (term to 6 mo), when intake was measured and anthropometry and blood sampling were performed. The results were analyzed using ANOVA. Although nutrient intake was similar, at 6 mo girls were lighter (6829 versus 7280 g) and shorter (64.4 versus 66.0 cm) than boys (p < 0.05). Patient characteristics were similar between the treatment groups. Although the volume of intake differed (B > C > A; p < 0.001), energy intake was similar in the groups. Because of differences in formula composition, protein, calcium, and phosphorus intakes differed (B < C < A; p < 0.001). Lower protein intakes were related to lower blood urea nitrogen levels (B < C < A; p < 0.001). At 6 mo, infant boys in B and C were lighter (6933, 6660 < 7949 g), shorter (65.3, 64.9 < 67.1 cm), and had a smaller head circumference (43.7, 43.7 < 44.8 cm; p < 0.05) than infants in group A. Preterm infants were found to increase their volume of intake to compensate for differences in energy density between formulas. After hospital discharge, infant boys fed a preterm formula grew faster than infant girls fed a preterm formula or infant boys fed a term formula.

A TEM study of two water-based adhesive systems bonded to dry and wet dentin

To keep the exposed collagen scaffold penetrable to resin, it has been recommended that the conditioned dentin surface be maintained in a visibly moist condition, a clinical technique commonly referred to as wet bonding. In this study, resin-dentin interfaces produced with two water-based adhesive systems--OptiBond (OPTI, Kerr) and Scotchbond Multi-Purpose (SBMP, 3M)--were compared by transmission electron microscopy, following the application of either a dry- or a wet-bonding technique. The hypothesis advanced was that the ultramorphology of the hybrid layer would differ depending on which bonding method was applied. A morphologically well-organized hybrid layer of collagen fibrils intermingled with resin in tiny interfibrillar channels was consistently formed by the OPTI system. The SBMP system was found to produce a hybrid layer with a more variable ultrastructure, less distinctly outlined collagen fibrils, and a characteristic electron-dense phase located at its surface. No major differences in hybrid layer ultrastructure were observed when the two adhesive systems investigated were bonded to either dry or wet dentin. When the adhesives were dry-bonded, no ultrastructural evidence of collapsed demineralized collagen, incompletely or not at all infiltrated by resin, could be detected. In addition, when the two adhesives were bonded to wet dentin, no signs of overwetting phenomena, that would have indicated that water was ineffectively removed, were apparent. It has been hypothesized that the amount of water provided with the hydrophilic primer solution of either of the two adhesive systems investigated suffices to re-hydrate and re-expand the gently air-dried and collapsed collagen network. Further research should be directed to determine whether this hypothesized self-rewetting effect can be extrapolated to other adhesive systems that provide water-based primers.

Epoxy-embedded versus nonembedded TEM examination of the resin-dentin interface

When transmission electron microscopy (TEM) is used to evaluate resin-dentin interface specimens for completeness of hybridization, the epoxy resin embedding medium that normally facilitates ultrathin sectioning may produce a secondary or artifactual hybrid layer. This secondary hybrid layer, composed of epoxy resin rather than adhesive resin, may fill the pores that remain as evidence of incomplete resin infiltration, obscuring the fact that they ever existed. In this study, resin-dentin interfaces produced by two dentin adhesive systems, Optibond (OPTI, Kerr) and Scotchbond Multi-Purpose (SBMP, 3M), were comparatively investigated by TEM in epoxy-embedded and nonembedded nondemineralized sections. The hypothesis advanced was that no difference in ultramorphology of the hybrid layer would result from either specimen preparation method. The two adhesive systems were applied to four mid-coronal dentin disks per manufacturer's instructions. One half of each sample was processed following common procedures for TEM sample preparation with epoxy embedding, whereas the other half was not embedded but instead immersed in hexamethyldisilazane (HMDS), dried and mounted so that it protruded from a base of cold-cure acrylic resin. Each sample was then sectioned using a diamond knife in an ultramicrotome. With either means of preparation, a hybrid layer with a relatively uniform electron density and a loose collagen fibril arrangement with electron lucent interfibrillar channels was formed by OPTI. At the base of the hybrid layer, collagen fibrils were anchored in the underlying unaffected dentin, and no microporosities or gaps were observed. Similarly, whether SBMP was embedded or nonembedded, it was found to have a hybrid layer of variable electron density and an electron dense phase localized at the surface of the hybrid layer. No porosities were evident at the base of the hybrid layer. Thus, with either of the two adhesive systems, no ultrastructural difference in hybrid layer formation was observed between epoxy-embedded and nonembedded sections, and no direct evidence of ineffective resin-infiltration of the demineralized collagen scaffold was found.