Pseudomonas aeruginosa strains recovered from chronic pulmonary infections in cystic fibrosis patients are frequently mucoid. Such strains express elevated levels of alginate but reduced levels of the aggregative polysaccharide Psl; however, the mechanistic basis for this regulation is not completely understood. Elevated pslA expression was observed in an amrZ null mutant and in strains expressing a DNA-binding-deficient AmrZ. AmrZ is a transcription factor that positively regulates twitching motility and alginate synthesis, two phenotypes involved in P. aeruginosa biofilm development. AmrZ bound directly to the pslA promoter in vitro, and molecular analyses indicate that AmrZ represses psl expression by binding to a site overlapping the promoter. Altered expression of amrZ in nonmucoid strains impacted biofilm structure and architecture, as structured microcolonies were observed with low AmrZ production and flat biofilms with amrZ overexpression. These biofilm phenotypes correlated with Psl levels, since we observed elevated Psl production in amrZ mutants and lower Psl production in amrZ-overexpressing strains. These observations support the hypothesis that AmrZ is a multifunctional regulator mediating transition of P. aeruginosa biofilm infections from colonizing to chronic biofilms through repression of the psl operon while activating the algD operon.
We explored dispositional differences in the ability to self-regulate attentional processes in the domain of public speaking. Participants first completed measures of speech anxiety and attentional control. In a second session, participants prepared and performed a short speech. Fear of public speaking negatively impacted performance only for those low in attentional control. Thus, attentional control appears to act as a buffer that facilitates successful self-regulation despite performance anxiety.
attention; attentional control; public speaking; self-regulation; anxiety
schizophrenia; cognitive behavior therapy; psychological therapy; meta-analysis
With the exception of target site mutations, insecticide resistance mechanisms in the principle malaria vector Anopheles gambiae, remains largely uncharacterized in Burkina Faso.
Here we detected high prevalence of resistance in Vallée du Kou (VK) to pyrethroids, DDT and dieldrin, moderate level for carbamates and full susceptibility to organophosphates. High frequencies of L1014F kdr (75%) and Rdl (87%) mutations were observed showing strong correlation with pyrethroids/DDT and dieldrin resistance. The frequency of ace1R mutation was low even in carbamate resistant mosquitoes. Microarray analysis identified genes significantly over-transcribed in VK. These include the cytochrome P450 genes, CYP6P3 and CYP6Z2, previously associated with pyrethroid resistance. Gene Ontology (GO) enrichment analysis suggested that elevated neurotransmitter activity is associated with resistance, with the over-transcription of target site resistance genes such as acetylcholinesterase and the GABA receptor. A rhodopsin receptor gene previously associated with pyrethroid resistance in Culex pipiens pallens was also over-transcribed in VK.
This study highlights the complex network of mechanisms conferring multiple resistance in malaria vectors and such information should be taken into account when designing and implementing resistance control strategies.
► High pyrethroids, DDT and dieldrin resistance in VK, moderate for carbamate ► High frequencies kdr and Rdl mutations in VK with strong correlation with resistance ► Detection using microarray of genes upregulated in VK notably CYP6P3 and CYP6Z2 P450s ► Neurotransmitter activity GO terms enriched in VK; Ace-1/GABA receptor upregulated ► A rhodopsin gene associated with resistance in Culex p. pallens upregulated in VK
VK, Vallée du Kou; DDT, dichlorodiphenyltrichloroethane; kdr, knockdown resistance; RDL, resistance to dieldrin; GO, Gene Ontology; MoH, Ministry of Health; IRS, indoor residual spraying; LLINs, long lasting insecticide nets; AChE, acetylcholinesterase; GSTs, glutathione-S-transferases; WHO, World Health Organization; SINE, short interspersed element; FC, fold change; sHSP, small Heat Shock Protein; qRT-PCR, quantitative reverse transcriptase polymerase chain reaction; GABA, gamma-aminobutyric acid; Anopheles gambiae; Malaria; Insecticide resistance; Burkina Faso; Microarray
Hand-assisted laparoscopic nephrectomy for polycystic kidney disease seemed to result in shorter length of hospital stay and reduced need for transfusion compared with patients undergoing the same procedure with an open technique.
Background and Objectives:
Historically, nephrectomy for autosomal dominant polycystic kidney disease was performed by an open technique. We performed this study to compare outcomes in hand-assisted laparoscopic nephrectomy with open nephrectomy in this population.
Charts of patients with autosomal dominant polycystic kidney disease who underwent nephrectomy by a transplant surgeon from January 1, 2000, to December 31, 2011, were reviewed. The hand-assisted laparoscopic nephrectomy group was compared with the open group. Data collected included unilateral versus bilateral nephrectomy, operative time, complications, transfusion requirement, and length of stay.
Of the 78 patients identified, 18 underwent open transabdominal nephrectomy, 56 underwent hand-assisted laparoscopic nephrectomy, and 2 underwent hand-assisted laparoscopic nephrectomy that was converted to an open procedure. Two patients were excluded because another major procedure was performed at the same time as the nephrectomy. Operative times were similar. Patients undergoing open bilateral nephrectomy were more likely to receive transfusion (odds ratio, 3.57 [95% confidence interval, 0.74–17.19]; P = .016), and the length of stay was longer in the open groups (5.9 days vs 4.0 days for unilateral [P = .013] and 7.8 days vs 4.6 days for bilateral [P = .001]). Overall complication rates were similar. The most frequent complications associated with hand-assisted laparoscopic nephrectomy were the development of an incisional hernia at the hand-port site and arteriovenous fistula thrombosis.
Hand-assisted laparoscopic nephrectomy can be safely performed without increased operative times or complications. The hand-assisted laparoscopic nephrectomy group enjoyed a shorter length of stay, and fewer patients in this group received transfusion. For patients considering renal transplantation, avoidance of transfusion is important to prevent sensitization and limiting access to compatible organs.
Nephrectomy; Polycystic kidney disease
This investigation evaluated standardized process of care data collected on selected hospitals serving a remote rural section of westernmost North Carolina.
Centers for Medicare and Medicaid Services data were analyzed retrospectively for multiple clinical parameters at Fannin Regional Hospital, Murphy Medical Center, and Union General Hospital. Data were analyzed by paired t-test for individual comparisons among the three study hospitals to compare the three facilities with each other, as well as with state and national average for each parameter.
Centers for Medicare and Medicaid Services “Hospital Compare” data from 2011 showed Fannin Regional Hospital to have significantly higher composite scores on standardized clinical process of care measures relative to the national average, compared with Murphy Medical Center (P = 0.01) and Union General Hospital (P = 0.01). This difference was noted to persist when Fannin Regional Hospital was compared with Union General Hospital using common state reference data (P = 0.02). When compared with national averages, mean process of care scores reported from Murphy Medical Center and Union General Hospital were both lower but not significantly different (−3.44 versus −6.07, respectively, P = 0.54).
The range of process of care scores submitted by acute care hospitals in western North Carolina is considerable. Centers for Medicare and Medicaid Services “Hospital Compare” information suggests that process of care measurements at Fannin Regional Hospital are significantly higher than at either Murphy Medical Center or Union General Hospital, relative to state and national benchmarks. Further investigation is needed to determine what impact these differences in process of care may have on hospital volume and/or market share in this region. Additional research is planned to identify process of care trends in this demographic and geographically rural area.
process of care; hospital quality; North Carolina; rural
Although a cure for HCV is on the near horizon, emerging drug cocktails will be expensive, associated with side-effects and resistance making a global vaccine an urgent priority given the estimated high incidence of infection around the world. Due to the highly heterogeneous nature of HCV, an effective HCV vaccine which could elicit broadly cross-neutralizing antibodies has represented a major challenge. In this study, we tested for the presence of cross-neutralizing antibodies in human volunteers who were immunized with recombinant glycoproteins gpE1/gpE2 derived from a single HCV strain (HCV1 of genotype 1a). Cross neutralization was tested in Huh-7.5 human hepatoma cell cultures using infectious recombinant HCV (HCVcc) expressing structural proteins of heterologous HCV strains from all known major genotypes, 1–7. Vaccination induced significant neutralizing antibodies against heterologous HCV genotype 1a virus which represents the most common genotype in North America. Of the 16 vaccinees tested, 3 were selected on the basis of strong 1a virus neutralization for testing of broad cross-neutralizing responses. At least 1 vaccinee was shown to elicit broad cross-neutralization against all HCV genotypes. Although observed in only a minority of vaccinees, our results prove the key concept that a vaccine derived from a single strain of HCV can elicit broad cross-neutralizing antibodies against all known major genotypes of HCV and provide considerable encouragement for the further development of a human vaccine against this common, global pathogen.
This case report outlines the investigation and management of a young patient presenting with left iliac fossa pain and sepsis. A CT was performed which was initially reported as not showing a perforation, however closer analysis provided evidence of subcutaneous emphysema in the anterior abdominal wall. This evidence justified urgent operative intervention. We review the evidence with regard to this presentation.
PRESENTATION OF CASE
A previously fit 24-year-old male presented with left iliac fossa pain and features of sepsis. A CT provided subtle but distinctive evidence of retroperitoneal perforation secondary to diverticulitis, in the form of surgical emphysema in the anterior abdominal wall. In view of this, urgent operation was considered justified on suspicion of visceral perforation. A diverticular perforation was confirmed intra-operatively, and a sigmoid colectomy with primary anastomosis was performed, together with a covering ileostomy. The patient made a good post-operative recovery.
Diverticular disease and its complications are becoming more common in a younger age group, in whom perforation may present late or may not be suspected. In this context special attention must be paid to any radiological evidence of perforation.
Surgical emphysema in the abdominal wall is an indicator of retroperitoneal perforation, and its presence should be excluded before the possibility of perforation is dismissed. This may be of especial value in younger age groups amongst whom perforation may be less clinically obvious.
Diverticulitis; Retroperitoneal; Perforation; Surgical emphysema
Trypanosoma cruzi, an intracellular protozoan etiologic agent of Chagas disease is covered by a dense coat of mucin-type glycoproteins, which is important to promote the parasite entry and persistence in the mammalian host cells. The O-glycosylation of T. cruzi mucins (Tc-mucins) is initiated by enzymatic addition of α-O-N-acetylglucosamine (GlcNAc) to threonine (Thr) by the UDP-GlcNAc:polypeptide α-N-acetylglucosaminyltransferase (pp-α-GlcNAcT) in the Golgi. The Tc-mucin is characterized by the presence of a high structural diversity of O-linked oligosaccharides found among different parasite strains, comprising two O-glycan Cores. In the Core 1, from strains principally associated with the domestic transmission cycle of Chagas disease, the GlcNAc O-4 is substituted with a β-galactopyranose (βGalp) unit, and in the most complex oligosaccharides the GlcNAc O-6 is further processed by the addition of β1 → 2-linked Galp residues creating a short linear Galp-containing chain. In the Core 2 structures, expressed by strains isolated from T. cruzi sylvatic hosts, the GlcNAc O-4 carries a β-galactofuranose (βGalf) unit and the GlcNAc O-6 can carry a branched Galpβ1 → 3[Galpβ1 → 2]Galpβ1 → 6 motif. The O-glycans carrying nonreducing terminal βGalp are available for sialylation by a surface T. cruzi trans-sialidase activity. Based on structural results, this review summarizes available data on the highly conserved process, which adds the GlcNAc unit in α-linkage to Thr residues the basis of the post-translational modification system in T. cruzi mucins. In addition, a mechanism unique employed by the parasite to transfer exogenous sialic acid residues to Tc-mucins is presented.
Trypanosoma cruzi; Posttranslational modification; Mucins; pp-α-GlcNAcT; trans-sialidase
End-stage liver disease caused by chronic hepatitis C virus (HCV) infection is the leading indication for liver transplantation in the Western world. However, immediate re-infection of the grafted donor liver by circulating virus is inevitable and progresses much faster than the original disease. Standard antiviral therapy is not well tolerated and usually ineffective in liver transplant patients while anti-HCV immunotherapy is hampered by the extreme genetic diversity of the virus and its ability to spread via cell-cell contacts.
We have generated a human monoclonal antibody against SR-BI, mAb16-71, that can efficiently prevent infection of Huh-7.5 hepatoma cells and primary hepatocytes by cell-culture-derived HCV (HCVcc). Using an Huh7.5 co-culture system we demonstrated that mAb16-71 interferes with direct cell-to-cell transmission of HCV. Finally we evaluated the in vivo efficacy of mAb16-71 in ‘human liver uPA-SCID mice’ (chimeric mice). A two-week anti-SR-BI therapy that was initiated one day before viral inoculation completely protected all chimeric mice from infection with serum-derived HCV of different genotypes. Moreover, a 9-day post-exposure therapy that was initiated 3 days after viral inoculation (when viremia was already observed in the animals) suppressed the rapid viral spread observed in untreated control animals. After cessation of anti-SR-BI-specific antibody therapy, a rise of the viral load was observed.
Using in vitro cell culture and human liver-chimeric mouse models, we show that a human monoclonal antibody targeting the HCV co-receptor SR-BI completely prevents infection and intrahepatic spread of multiple HCV genotypes. This strategy may be an efficacious way to prevent infection of allografts following liver transplantation in chronic HCV patients, and may even hold promise for the prevention of virus rebound during or following anti-viral therapy.
liver transplantation; HCV; chimeric mice; prevention; immunotherapy
Iron is an essential nutrient for most bacterial pathogens, but is restricted by the host immune system. Mycobacterium tuberculosis (Mtb) utilizes two classes of small molecules, mycobactins and carboxymycobactins, to capture iron from the human host. Here, we show that an Mtb mutant lacking the mmpS4 and mmpS5 genes did not grow under low iron conditions. A cytoplasmic iron reporter indicated that the double mutant experienced iron starvation even under high-iron conditions. Loss of mmpS4 and mmpS5 did not change uptake of carboxymycobactin by Mtb. Thin layer chromatography showed that the ΔmmpS4/S5 mutant was strongly impaired in biosynthesis and secretion of siderophores. Pull-down experiments with purified proteins demonstrated that MmpS4 binds to a periplasmic loop of the associated transporter protein MmpL4. This interaction was corroborated by genetic experiments. While MmpS5 interacted only with MmpL5, MmpS4 interacted with both MmpL4 and MmpL5. These results identified MmpS4/MmpL4 and MmpS5/MmpL5 as siderophore export systems in Mtb and revealed that the MmpL proteins transport small molecules other than lipids. MmpS4 and MmpS5 resemble periplasmic adapter proteins of tripartite efflux pumps of Gram-negative bacteria, however, they are not only required for export but also for efficient siderophore synthesis. Membrane association of MbtG suggests a link between siderophore synthesis and transport. The structure of the soluble domain of MmpS4 (residues 52–140) was solved by NMR and indicates that mycobacterial MmpS proteins constitute a novel class of transport accessory proteins. The bacterial burden of the mmpS4/S5 deletion mutant in mouse lungs was lower by 10,000-fold and none of the infected mice died within 180 days compared to wild-type Mtb. This is the strongest attenuation observed so far for Mtb mutants lacking genes involved in iron utilization. In conclusion, this study identified the first components of novel siderophore export systems which are essential for virulence of Mtb.
In the late 19th century the French physician Armand Trousseau recognized that treating anemic tuberculosis patients with iron salts exacerbated the disease. In 1911 Twort postulated that mycobacteria produce an essential growth factor which was identified in 1953 as mycobactin. The hydrophobic mycobactin and its more water-soluble cousin carboxymycobactin are small molecules made by Mycobacterium tuberculosis to scavenge iron from its human host. While the biosynthesis of these siderophores has been decoded, it was unknown how M. tuberculosis secretes these molecules. In this study, we identified two similar transport systems, MmpS4/MmpL4 and MmpS5/MmpL5, which are required for biosynthesis and export of siderophores by M. tuberculosis. The lack of these transport systems drastically decreased the number of M. tuberculosis cells in the lungs and spleens of infected mice. Lung examination and histological assessment in mice infected with the mmpS4/S5 deletion strain showed almost no signs of infection. Further, none of the mice infected with this strain died within 180 days in contrast to wild-type M. tuberculosis. In this study, we identified the first components of a novel siderophore export system in M. tuberculosis and showed the importance of siderophore export for virulence of M. tuberculosis.
This study measured the effects of two previously untested practical considerations - venting and transmission delays - on speech intelligibility in a simulated unilateral wireless system, where a target signal in background noise was transmitted wirelessly to the hearing-impaired (HI) listener.
Speech reception thresholds (SRTs) relative to the signal-to-noise ratio (SNR) were measured by varying the surrounding babble noise level. The target signal was presented at 0° azimuth in the soundfield and unilaterally via an insert earphone, using open and closed fittings with simulated-wireless delays ranging between 0-160 ms. SRTs were also measured unaided and with participants’ current hearing aid(s).
Thirty-three mild-to-moderate sensorineural HI adults participated in the experiment.
For an open fitting, the results showed a 5-dB SNR benefit in SRT compared to unaided performance at shorter delays. For a closed fitting, the majority of participants could accurately recognize speech below −20 dB SNR across delays.
These results highlight the efficacy of wireless systems with HI adults. Speech-intelligibility benefits are affected by transmission delays only when the delay is greater than 40 ms and the coupling is vented.
Hearing impairment; speech intelligibility; wireless technology
Hepatitis C virus (HCV) replication in primary liver cells is less robust than that in hepatoma cell lines, suggesting that innate antiviral mechanisms in primary cells may limit HCV replication or spread. Here, we analyzed expression of 47 genes associated with interferon (IFN) induction and signaling following HCV infection of primary human fetal liver cell (HFLC) cultures from 18 different donors. We report that cell culture-produced HCV (HCVcc) induced expression of Type III (λ) IFNs and of IFN-stimulated genes (ISGs). Little expression of Type I IFNs was detected. Levels of IFNλ and ISG induction varied among donors and, often, between adapted and non-adapted HCV chimeric constructs. Higher levels of viral replication were associated with greater induction of ISGs and of λ IFNs. Gene induction was dependent on HCV replication, as UV-inactivated virus was not stimulatory and an antiviral drug, 2′-C-methyladenosine, reduced induction of λ IFNs and ISGs. The level of IFNλ protein induced was sufficient to inhibit HCVcc infection of naïve cultures.
Together, these results indicate that despite its reported abilities to blunt the induction of an IFN response, HCV infection is capable of inducing antiviral cytokines and pathways in primary liver cell cultures. Induction of ISGs and λ IFNs may limit the growth and spread of HCV in primary cell cultures and in the infected liver. HCV infection of HFLC may provide a useful model for the study of gene induction by HCV in vivo.
Hepacivirus; Type III IFN; Type I IFN; hepatocyte; RT-PCR
Here, we demonstrate that primary cultures of human fetal liver cells (HFLC) reliably support infection with laboratory strains of HCV, although levels of virus replication vary significantly between different donor cell preparations and frequently decline in a manner suggestive of active viral clearance. To investigate possible contributions of the interferon (IFN) system to control of HCV infection in HFLC, we exploited the well-characterized ability of paramyxovirus (PMV) V proteins to counteract both IFN induction and antiviral signaling. The V proteins of measles virus (MV) and parainfluenza virus 5 (PIV5) were introduced into HFLC using lentiviral vectors encoding a fluorescent reporter for visualization of HCV-infected cells. V protein-transduced HFLC supported enhanced (10–100 fold) levels of HCV infection relative to un-transduced or control vector-transduced HFLC. Infection was assessed by measurement of virus-driven luciferase, by assays for infectious HCV and viral RNA, and by direct visualization of HCV-infected hepatocytes. Live cell imaging between 48 and 119 hrs post-infection demonstrated little or no spread of infection in the absence of PMV V protein expression. In contrast, V protein-transduced HFLC showed numerous HCV infection events. V protein expression efficiently antagonized the HCV-inhibitory effects of added IFNs in HFLC. In addition, induction of the type III IFN, IL29, following acute HCV infection was inhibited in V protein-transduced cultures.
These studies suggest that the cellular IFN response plays a significant role in limiting the spread of HCV infection in primary hepatocyte cultures. Strategies aimed at dampening this response may be key to further development of robust HCV culture systems, enabling studies of virus pathogenicity, and the mechanisms by which HCV spreads in its natural host cell population.
Hepatocyte; Parainfluenza virus; measles virus; interferon; STAT
Essential thrombocythaemia (ET) is a rare clonal myeloproliferative disorder characterized by a sustained elevation in platelet count and megakaryocyte hyperplasia. Anagrelide is used in the treatment of ET, where it has been shown to reduce platelet count. Anagrelide is metabolized by cytochrome P450 (CYP) 1A2, and previous studies of the effect of food on the bioavailability and pharmacokinetics of anagrelide were conducted prior to the identification of the active metabolite, 3-hydroxyanagrelide.
The objectives of this study were to determine the effect of food and caffeine on the pharmacokinetics of anagrelide and its active metabolite, 3-hydroxyanagrelide, to monitor electrocardiogram (ECG) parameters following drug administration, and to document the relationship between palpitations, ECG changes and caffeine intake
Thirty-five healthy subjects who received 1 mg of anagrelide following either a 10-h fast or within 30 min of a standardized breakfast, including two cups of coffee, were studied.
Time to maximum (peak) plasma concentration (Cmax) of anagrelide was 4.0 h in the fed and 1.5 h in the fasted group (p < 0.05); similar results were observed for 3-hydroxyanagrelide. The mean Cmax of anagrelide was 4.45 ± 2.32 ng/mL and 5.08 ± 2.99 ng/mL in the fed/caffeine and fasted groups, respectively; peak concentrations were higher for 3-hydroxyanagrelide in both the fed/caffeine and fasted groups. The most frequent adverse events (AEs) were headache (60 %) and palpitations (40 %). There were no serious AEs and all ECGs were normal, although significant reductions in PR interval, QRS length and QT interval were observed in both groups. Heart rate increased after anagrelide administration in both fed/caffeine and fasted states (p < 0.01); however, increased heart rate was significantly more frequent in the fed/caffeine state than in the fasted state (p < 0.001 for heart rate increase in the first hour after drug administration). There was a trend towards a greater heart rate increase in subjects reporting palpitations than in those without (mean heart rate ± SD at 1 h: 10.1 ± 6.4 vs. 8.0 ± 8.4 beats/min [p = 0.35]; at 4 h: 12.7 ± 7.5 vs. 9.1 ± 8.8 beats/min [p = 0.10], respectively).
We conclude that food/caffeine delayed absorption of anagrelide. Anagrelide was generally well tolerated and had small effects on ECG parameters and heart rate. Caffeine may be implicated in a higher increase in heart rate and increased frequency of palpitations observed following administration of anagrelide with food/caffeine versus fasting.
Osmolytes are small, chemically diverse, organic solutes that function as an essential component of cellular stress response. Protecting osmolytes enhance protein stability via preferential exclusion, and non-protecting osmolytes, such as urea, destabilize protein structures. Although much is known about osmolyte effects on proteins, less is understood about osmolyte effects on nucleic acids and their counterion atmospheres. Non-protecting osmolytes destabilize nucleic acid structures, but effects of protecting osmolytes depend on numerous factors including the type of nucleic acid and the complexity of the functional fold. To begin quantifying protecting osmolyte effects on nucleic acid interactions we used small angle x-ray scattering (SAXS) techniques to monitor DNA duplexes in the presence of sucrose. This protecting osmolyte is a commonly used contrast matching agent in SAXS studies of protein-nucleic acid complexes, thus it is important to characterize interaction changes induced by sucrose. Measurements of interactions between duplexes showed no dependence on the presence of up to 30% sucrose except under high Mg2+ conditions where stacking interactions were disfavored. The number of excess ions associated with DNA duplexes, reported by anomalous small angle x-ray scattering (ASAXS) experiments, was sucrose independent. Although protecting osmolytes can destabilize secondary structures, our results suggest that ion atmospheres of individual duplexes remain unperturbed by sucrose.
In recent years mass spectrometry based techniques have emerged as structural biology tools for the characterization of macromolecular, non-covalent assemblies. Many of these efforts involve preservation of intact protein complexes within the mass spectrometer, providing molecular weight measurements that allow the determination of subunit stoichiometry and real-time monitoring of protein interactions. Attempts have been made to further elucidate subunit architecture through the dissociation of subunits from the intact complex by colliding it into inert gas atoms such as argon or xenon. Unfortunately, the amount of structural information that can be derived from such strategies is limited by the nearly ubiquitous ejection of a single, unfolded subunit. Here, we present results from the gas-phase dissociation of protein-protein complexes upon collision into a surface. Dissociation of a series of tetrameric and pentameric proteins demonstrate that alternative subunit fragments, not observed through multiple collisions with gas atoms, can be generated through surface collision. Evidence is presented for the retention of individual subunit structure, and in some cases, retention of non-covalent interactions between subunits and ligands. We attribute these differences to the rapid large energy input of ion-surface collisions, which leads to the dissociation of subunits prior to the unfolding of individual monomers.
In the city of Bobo-Dioulasso in Burkina Faso, Anopheles arabiensis has superseded Anopheles gambiae s.s. as the major malaria vector and the larvae are found in highly polluted habitats normally considered unsuitable for Anopheles mosquitoes. Here we show that An. gambiae s.l. adults emerging from a highly polluted site in the city centre (Dioulassoba) have a high prevalence of DDT resistance (percentage mortality after exposure to diagnostic dose = 65.8% in the dry season and 70.4% in the rainy season, respectively). An investigation into the mechanisms responsible found an unexpectedly high frequency of the 1014S kdr mutation (allele frequency = 0.4), which is found at very low frequencies in An. arabiensis in the surrounding rural areas, and an increase in transcript levels of several detoxification genes, notably from the glutathione transferase and cytochrome P450 gene families. A number of ABC transporter genes were also expressed at elevated levels in the DDT resistant An. arabiensis. Unplanned urbanisation provides numerous breeding grounds for mosquitoes. The finding that Anopheles mosquitoes adapted to these urban breeding sites have a high prevalence of insecticide resistance has important implications for our understanding of the selective forces responsible for the rapid spread of insecticide resistant populations of malaria vectors in Africa.
Congenital muscular torticollis (CMT) is the third commonest congenital deformity, commonly presenting in the first week of life. Due to contracture and shortening of the sternocleidomastoid muscle, the head is tilted towards the affected side; however there may also be a varying degree of rotation towards the contralateral side. Most infants with CMT can be managed non-surgically, however if this is unsuccessful surgery may be necessary, with many different techniques described. In this case report, we describe a 17-year old woman with persistent left sided CMT despite botulinum toxin paralysis that was successfully treated with surgery.
congenital muscular torticollis; idiopathic torticollis.
Preventing malaria used to seem as simple as killing the vector, the mosquito; however, a recent study shows that this concept is now anything but simple. The highly effective use of insecticide-treated bed nets and indoor insecticide spraying is being challenged by mosquito resistance to insecticides. In West Africa, populations of this mosquito vector are now resistant to all 4 classes of insecticide approved for this use. And no new classes of insecticide are anticipated until 2020, at the earliest. Development of newer classes of insecticide is crucial because if resistance continues unchecked, the hard-earned progress in malaria control in Africa could be quickly reversed.
Malaria control depends on mosquito susceptibility to insecticides. We tested Anopheles gambiae mosquitoes from Côte d’Ivoire for resistance and screened a subset for target site mutations. Mosquitoes were resistant to insecticides of all approved classes. Such complete resistance, which includes exceptionally strong phenotypes, presents a major threat to malaria control.
pyrethroids; DDT; organophosphates; carbamates; acetylcholinesterase; Anopheles gambiae; mosquitoes; Côte d’Ivoire; malaria; vector-borne infections; insecticide resistance
During in vitro fertilization (IVF), fertility patients are expected to self-administer many injections as part of this treatment. While newer medications have been developed to substantially reduce the number of these injections, such agents are typically much more expensive. Considering these differences in both cost and number of injections, this study compared patient preferences between GnRH-agonist and GnRH-antagonist based protocols in IVF.
Data were collected by voluntary, anonymous questionnaire at first consultation appointment. Patient opinion concerning total number of s.c. injections as a function of non-reimbursed patient cost associated with GnRH-agonist [A] and GnRH-antagonist [B] protocols in IVF was studied.
Completed questionnaires (n = 71) revealed a mean +/− SD patient age of 34 +/− 4.1 yrs. Most (83.1%) had no prior IVF experience; 2.8% reported another medical condition requiring self-administration of subcutaneous medication(s). When out-of-pocket cost for [A] and [B] were identical, preference for [B] was registered by 50.7% patients. The tendency to favor protocol [B] was weaker among patients with a health occupation. Estimated patient costs for [A] and [B] were $259.82 +/− 11.75 and $654.55 +/− 106.34, respectively (p < 0.005). Measured patient preference for [B] diminished as the cost difference increased.
This investigation found consistently higher non-reimbursed direct medication costs for GnRH-antagonist IVF vs. GnRH-agonist IVF protocols. A conditional preference to minimize downregulation (using GnRH-antagonist) was noted among some, but not all, IVF patient sub-groups. Compared to IVF patients with a health occupation, the preference for GnRH-antagonist was weaker than for other patients. While reducing total number of injections by using GnRH-antagonist is a desirable goal, it appears this advantage is not perceived equally by all IVF patients and its utility is likely discounted heavily by patients when nonreimbursed medication costs reach a critical level.
GnRH-antagonist; IVF; Preference; Patient cost; Health economics
Effective delivery of cardiopulmonary resuscitation (CPR) and prompt defibrillation following sudden cardiac arrest (SCA) is vital. Updated guidelines for adult basic life support (BLS) were published in 2010 by the European Resuscitation Council (ERC) in an effort to improve survival following SCA. There has been little assessment of the ability of rescuers to meet the standards outlined within these new guidelines.
We conducted a retrospective analysis of the performance of first year healthcare students trained and assessed using either the new 2010 ERC guidelines or their 2005 predecessor, within the University of Birmingham, United Kingdom. All students were trained as lay rescuers during a standardised eight hour ERC-accredited adult BLS course.
We analysed the examination records of 1091 students. Of these, 561 were trained and assessed using the old 2005 ERC guidelines and 530 using the new 2010 guidelines. A significantly greater proportion of candidates failed in the new guideline group (16.04% vs. 11.05%; p < 0.05), reflecting a significantly greater proportion of lay-rescuers performing chest compressions at too fast a rate when trained and assessed with the 2010 rather than 2005 guidelines (6.04% vs. 2.67%; p < 0.05). Error rates for other skills did not differ between guideline groups.
The new ERC guidelines lead to a greater proportion of lay rescuers performing chest compressions at an erroneously fast rate and may therefore worsen BLS efficacy. Additional study is required in order to define the clinical impact of compressions performed to a greater depth and at too fast a rate.
Adult; Basic life support (BLS); Cardiopulmonary resuscitation (CPR); 2005 European Resuscitation Council (ERC) guidelines; 2010 European Resuscitation Council (ERC) guidelines; Cardiac arrest
The type I interferon (IFN) response protects cells from invading viral pathogens. The cellular factors that mediate this defense are the products of interferon-stimulated genes (ISGs). Although hundreds of ISGs have been identified since their discovery over 25 years ago1,2,3, only few have been characterized with respect to antiviral activity. For most, little is known about their antiviral potential, their target specificity, and their mechanisms of action. Using an overexpression screening approach, we show that different viruses are targeted by unique sets of ISGs, with each viral species susceptible to multiple antiviral genes with a range of inhibitory activities. To conduct the screen, over 380 ISGs were tested for their ability to inhibit the replication of several important viruses including hepatitis C virus (HCV), yellow fever virus (YFV), West Nile virus (WNV), chikungunya virus (CHIKV), Venezuelan equine encephalitis virus (VEEV), and human immunodeficiency virus (HIV-1). Broadly acting effectors included IRF1, C6orf150, HPSE, RIG-I, MDA5, and IFITM3, while more targeted antiviral specificity was observed with DDX60, IFI44L, IFI6, IFITM2, MAP3K14, MOV10, NAMPT, OASL, RTP4, TREX1, and UNC84B. Combined expression of two-ISG pairs showed additive antiviral effects similar to moderate IFN doses. Mechanistic studies revealed a common theme of translational inhibition for numerous effectors. Several ISGs, including ADAR, FAM46C, LY6E, and MCOLN2, enhanced replication of certain viruses, highlighting another layer of complexity in the highly pleiotropic IFN system.
Background and methods
A longitudinal Anopheles gambiae s.l. insecticide-resistance monitoring programme was established in four sentinel sites in Burkina Faso. For three years, between 2008 and 2010, WHO diagnostic dose assays were used to measure the prevalence of resistance to all the major classes of insecticides at the beginning and end of the malaria transmission season. Species identification and genotyping for target site mutations was also performed and the sporozoite rate in adults determined.
At the onset of the study, resistance to DDT and pyrethroids was already prevalent in An. gambiae s.l. from the south-west of the country but mosquitoes from the two sites in central Burkina Faso were largely susceptible. Within three years, DDT and permethrin resistance was established in all four sites. Carbamate and organophosphate resistance remains relatively rare and largely confined to the south-western areas although a small number of bendiocarb survivors were found in all sites by the final round of monitoring. The ace-1R target site resistance allele was present in all localities and its frequency exceeded 20% in 2010 in two of the sites. The frequency of the 1014F kdr mutation increased throughout the three years and by 2010, the frequency of 1014F in all sites combined was 0.02 in Anopheles arabiensis, 0.56 in An. gambiae M form and 0.96 in An. gambiae S form. This frequency did not differ significantly between the sites. The 1014S kdr allele was only found in An. arabiensis but its frequency increased significantly throughout the study (P = 0.0003) and in 2010 the 1014S allele frequency was 0.08 in An. arabiensis. Maximum sporozoite rates (12%) were observed in Soumousso in 2009 and the difference between sites is significant for each year.
Pyrethroid and DDT resistance is now established in An. gambiae s.l. throughout Burkina Faso. Results from diagnostic dose assays are highly variable within and between rounds of testing, and hence it is important that resistance monitoring is carried out on more than one occasion before decisions on insecticide procurement for vector control are made. The presence of 1014S in An. gambiae s.l., in addition to 1014F, is not unexpected given the recent report of 1014S in Benin but highlights the importance of monitoring for both mutations throughout the continent. Future research must now focus on the impact that this resistance is having on malaria control in Burkina Faso.
Malaria; Anopheles gambiae; kdr; Insecticide; Resistance; 1014F; 1014S; ace-1R