Genomic description of acquired fluconazole- and echinocandin-resistance in patients with serial Candida glabrata isolates

Candida glabrata is one of the most common causes of systemic candidiasis, often resistant to antifungal medications. To describe the genomic context of emerging resistance, we conducted a retrospective analysis of 82 serially collected isolates from 33 patients from population-based candidemia surveillance in the United States. We used whole-genome sequencing to determine the genetic relationships between isolates obtained from the same patient. Phylogenetic analysis demonstrated that isolates from 29 patients were clustered by patient. The median SNPs between isolates from the same patient was 30 (range: 7-96 SNPs), while unrelated strains infected four patients. Twenty-one isolates were resistant to echinocandins, and 24 were resistant to fluconazole. All echinocandin-resistant isolates carried a mutation either in the FKS1 or FKS2 HS1 region. Of the 24 fluconazole-resistant isolates, 17 (71%) had non-synonymous polymorphisms in the PDR1 gene, which were absent in susceptible isolates. In 11 patients, a genetically related resistant isolate was collected after recovering susceptible isolates, indicating in vivo acquisition of resistance. These findings allowed us to estimate the intra-host diversity of C. glabrata and propose an upper boundary of 96 SNPs for defining genetically related isolates, which can be used to assess donor-to-host transmission, nosocomial transmission, or acquired resistance. IMPORTANCE In our study, mutations associated to azole resistance and echinocandin resistance were detected in Candida glabrata isolates using a whole-genome sequence. C. glabrata is the second most common cause of candidemia in the United States, which rapidly acquires resistance to antifungals, in vitro and in vivo.

Synthesis, structure-activity relationships, cocrystallization and cellular characterization of novel smHDAC8 inhibitors for the treatment of schistosomiasis

Schistosomiasis is a major neglected parasitic disease that affects more than 265 million people worldwide and for which the control strategy consists of mass treatment with the only available drug, praziquantel. In this study, we chemically optimized our previously reported benzhydroxamate-based inhibitors of Schistosoma mansoni histone deacetylase 8 (smHDAC8). Crystallographic analysis provided insights into the inhibition mode of smHDAC8 activity by the highly potent inhibitor 5o. Structure-based optimization of the novel inhibitors was carried out using the available crystal structures as well as docking studies on smHDAC8. The compounds were evaluated in screens for inhibitory activity against schistosome and human HDACs (hHDAC). The in vitro and docking results were used for detailed structure activity relationships. The synthesized compounds were further investigated for their lethality against the schistosome larval stage using a fluorescence-based assay. The most promising inhibitor 5o showed significant dose-dependent killing of the schistosome larvae and markedly impaired egg laying of adult worm pairs maintained in culture.

Robotic-assisted, laparoscopic, and open incisional hernia repair: early outcomes from the Prospective Hernia Study

PURPOSE

To provide a comparative analysis of short-term outcomes after open, laparoscopic, and robotic-assisted (RAS) ventral incisional hernia (VIH) repairs that include subject-reported pain medication usage and hernia-related quality of life (QOL).

METHODS

Subjects were ≥ 18 years old and underwent elective open, laparoscopic or RAS VIH repair without myofascial release. Perioperative clinical outcomes through 30 days were analyzed as were prescription pain medication use and subject-reported responses to the HerQLes Abdominal QOL questionnaire. Observed differences in baseline characteristics were controlled using a weighted propensity score analysis to obviate potential selection bias (inverse probability of treatment weighting, IPTW). A p value < 0.05 was considered statistically significant.

RESULTS

Three hundred and seventy-one subjects (RAS, n = 159; open, n = 130; laparoscopic, n = 82) were enrolled in the study across 17 medical institutions within the United States. Operative times were significantly different between the RAS and laparoscopic groups (126.2 vs 57.2, respectively; p < 0.001). Mean length of stay was comparable for RAS vs laparoscopic (1.4 ± 1.0 vs 1.4 ± 1.1, respectively; p = 0.623) and differed for the RAS vs open groups (1.4 ± 1.0 vs 2.0 ± 1.9, respectively; p < 0.001). Conversion rates differed between RAS and laparoscopic groups (0.6% vs 4.9%; p = 0.004). The number of subjects reporting the need to take prescription pain medication through the 2-4 weeks visit differed between RAS vs open (65.2% vs 79.8%; p < 0.001) and RAS vs laparoscopic (65.2% vs 78.75%; p < 0.001). For those taking prescription pain medication, the mean number of pills taken was comparable for RAS vs open (23.3 vs 20.4; p = 0.079) and RAS vs laparoscopic (23.3 vs 23.3; p = 0.786). Times to return to normal activities and to work, complication rates and HerQLes QOL scores were comparable for the RAS vs open and RAS vs laparoscopic groups. The reoperation rate within 30 days post-procedure was comparable for RAS vs laparoscopic (0.6% vs 0%; p = 0.296) and differed for RAS vs open (0.6% vs 3.1%; p = 0.038).

CONCLUSIONS

Short-term outcomes indicate that open, laparoscopic, and robotic-assisted approaches are effective surgical approaches to VIH repair; however, each repair technique may demonstrate advantages in terms of clinical outcomes. Observed differences in the RAS vs laparoscopic comparison are longer operative time and lower conversion rate in the RAS group. Observed differences in the RAS vs open comparison are shorter LOS and lower reoperation rate through 30 days in the RAS group. The operative time in the RAS vs open comparison is similar. The number of subjects requiring the use of prescription pain medication favored the RAS group in both comparisons; however, among subjects reporting a need for pain medication, there was no difference in the number of prescription pain medication pills taken. While the study adds to the body of evidence evaluating the open, laparoscopic, and RAS approaches, future controlled studies are needed to better understand pain and QOL outcomes related to incisional hernia repair.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02715622.

Histone deacetylase inhibition modulates histone acetylation at gene promoter regions and affects genome-wide gene transcription in Schistosoma mansoni

BACKGROUND

Schistosomiasis is a parasitic disease infecting hundreds of millions of people worldwide. Treatment depends on a single drug, praziquantel, which kills the Schistosoma spp. parasite only at the adult stage. HDAC inhibitors (HDACi) such as Trichostatin A (TSA) induce parasite mortality in vitro (schistosomula and adult worms), however the downstream effects of histone hyperacetylation on the parasite are not known.

METHODOLOGY/PRINCIPAL FINDINGS

TSA treatment of adult worms in vitro increased histone acetylation at H3K9ac and H3K14ac, which are transcription activation marks, not affecting the unrelated transcription repression mark H3K27me3. We investigated the effect of TSA HDACi on schistosomula gene expression at three different time points, finding a marked genome-wide change in the transcriptome profile. Gene transcription activity was correlated with changes on the chromatin acetylation mark at gene promoter regions. Moreover, combining expression data with ChIP-Seq public data for schistosomula, we found that differentially expressed genes having the H3K4me3 mark at their promoter region in general showed transcription activation upon HDACi treatment, compared with those without the mark, which showed transcription down-regulation. Affected genes are enriched for DNA replication processes, most of them being up-regulated. Twenty out of 22 genes encoding proteins involved in reducing reactive oxygen species accumulation were down-regulated. Dozens of genes encoding proteins with histone reader motifs were changed, including SmEED from the PRC2 complex. We targeted SmEZH2 methyltransferase PRC2 component with a new EZH2 inhibitor (GSK343) and showed a synergistic effect with TSA, significantly increasing schistosomula mortality.

CONCLUSIONS/SIGNIFICANCE

Genome-wide gene expression analyses have identified important pathways and cellular functions that were affected and may explain the schistosomicidal effect of TSA HDACi. The change in expression of dozens of histone reader genes involved in regulation of the epigenetic program in S. mansoni can be used as a starting point to look for possible novel schistosomicidal targets.

Meticillin-resistant Staphylococcus aureus (MRSA) acquisition risk in an endemic neonatal intensive care unit with an active surveillance culture and decolonization programme

BACKGROUND

Meticillin-resistant Staphylococcus aureus (MRSA) is a leading cause of healthcare-associated infection in the neonatal intensive care unit (NICU). Decolonization may eliminate bacterial reservoirs that drive MRSA transmission.

AIM

To measure the association between colonization pressure from decolonized and non-decolonized neonates and MRSA acquisition to inform use of this strategy for control of endemic MRSA.

METHODS

An eight-year retrospective cohort study was conducted in a level-4 NICU that used active surveillance cultures and decolonization for MRSA control. Weekly colonization pressure exposures were defined as the number of patient-days of concurrent admission with treated (decolonized) and untreated (non-decolonized) MRSA carriers in the preceding seven days. Poisson regression was used to estimate risk of incident MRSA colonization associated with colonization pressure exposures. The population-attributable fraction was calculated to assess the proportion of overall unit MRSA incidence attributable to treated or untreated patients in this setting.

FINDINGS

Every person-day increase in exposure to an untreated MRSA carrier was associated with a 6% increase in MRSA acquisition risk [relative risk (RR): 1.06; 95% confidence interval (CI): 1.01-1.11]. Risk of acquisition was not influenced by exposure to treated, isolated MRSA carriers (RR: 1.01; 95% CI: 0.98-1.04). In the context of this MRSA control programme, 22% (95% CI: 4.0-37) of MRSA acquisition could be attributed to exposures to untreated MRSA carriers.

CONCLUSION

Untreated MRSA carriers were an important reservoir for transmission. Decolonized patients on contact isolation posed no detectable transmission threat, supporting the hypothesis that decolonization may reduce patient-to-patient transmission. Non-patient reservoirs may contribute to unit MRSA acquisition and require further investigation.

Association of thrombophilia and catheter-associated thrombosis in children: a systematic review and meta-analysis

Essentials It is unclear if thrombophilia increases the risk of catheter-associated thrombosis in children. We conducted a meta-analysis on thrombophilia and pediatric catheter-associated thrombosis. Presence of ≥1 trait confers additional risk of venous thrombosis in children with catheters. Limitations of included studies preclude us from recommending routine thrombophilia testing.

SUMMARY

Background The association between thrombophilia and deep vein thrombosis (DVT) associated with central venous catheter (CVC) use, the most important pediatric risk factor for thrombosis, is unclear in children. Pediatric studies with small sample sizes have reported conflicting results. We sought to evaluate whether, among children with CVCs, thrombophilia increases the risk of CVC-associated DVT (CADVT). Materials and methods We systematically searched MEDLINE, EMBASE, the Web of Science, the Cochrane Central Register for Controlled Trials, PubMed and reference lists for controlled studies published from the inception of the database until September 2015. Included were studies of children aged <21 years with CVCs who were systematically tested for thrombophilic traits that are commonly screened for in clinical practice. Pooled prevalence rates and pooled odds ratios (pORs) of CADVT with thrombophilia were estimated by use of a random effects model. Results We analyzed 16 cohort studies with 1279 children, 277 of whom had CADVT, and with 12 traits tested. There was significant heterogeneity in the included studies. The presence of one or more traits was associated with CADVT (pOR 3.20; 95% confidence interval [CI] 1.56-6.54). Although the prevalence of most traits was < 0.10, children with protein C deficiency, elevated factor VIII levels and the FV Leiden mutation had an increased prevalence of CADVT. The association with thrombophilia seemed to be stronger for symptomatic CADVT (pOR 6.71; 95% CI 1.93-23.37) than for asymptomatic CADVT (pOR 2.14; 95% CI 1.10-4.18). Conclusions On the basis of the low prevalence of specific traits, the relatively weak association with CADVT, and the limitations of the included studies, we cannot recommend routine testing of thrombophilias in children with CADVT.

Anaplasma phagocytophilum increases the levels of histone modifying enzymes to inhibit cell apoptosis and facilitate pathogen infection in the tick vector Ixodes scapularis

Epigenetic mechanisms have not been characterized in ticks despite their importance as vectors of human and animal diseases worldwide. The objective of this study was to characterize the histones and histone modifying enzymes (HMEs) of the tick vector Ixodes scapularis and their role during Anaplasma phagocytophilum infection. We first identified 5 histones and 34 HMEs in I. scapularis in comparison with similar proteins in model organisms. Then, we used transcriptomic and proteomic data to analyze the mRNA and protein levels of I. scapularis histones and HMEs in response to A. phagocytophilum infection of tick tissues and cultured cells. Finally, selected HMEs were functionally characterized by pharmacological studies in cultured tick cells. The results suggest that A. phagocytophilum manipulates tick cell epigenetics to increase I. scapularis p300/CBP, histone deacetylase, and Sirtuin levels, resulting in an inhibition of cell apoptosis that in turn facilitates pathogen infection and multiplication. These results also suggest that a compensatory mechanism might exist by which A. phagocytophilum manipulates tick HMEs to regulate transcription and apoptosis in a tissue-specific manner to facilitate infection, but preserving tick fitness to guarantee survival of both pathogens and ticks. Our study also indicates that the pathogen manipulates arthropod and vertebrate cell epigenetics in similar ways to inhibit the host response to infection. Epigenetic regulation of tick biological processes is an essential element of the infection by A. phagocytophilum and the study of the mechanisms and principal actors involved is likely to provide clues for the development of anti-tick drugs and vaccines.

Intersatellite range monitoring using optical interferometry

We report on an interferometer designed to provide 1-10 nm/square root(Hz) displacement measurement resolution, in the range 0.01 Hz to 1 Hz, while in low Earth orbit. The interferometer comprises two units, each with its own laser and in separate satellites, which would be in the same orbit separated by approximately 50 km. We discuss the requirements on the interferometer subsystem and describe the optical transponder distance measurement, including a phase locking method to generate a heterodyne beat signal between the two lasers. Design, fabrication, and testing of a "flightlike" engineering model interferometer is outlined, and results from environmental and performance tests are reported.

Census, molecular characterization and developmental expression of Leucine-Rich-Repeat proteins in Plasmodium falciparum

The capacity of Leucine-Rich Repeat or LRR proteins to interact with many ligands enables them to contribute to important cellular functions ranging from the regulation of the cell cycle to protein trafficking and signal transduction. In Plasmodium falciparum, little is known about the expression of these LRR proteins. Here, we identified the PfLRR genes and determined their transcriptional expression during the intraerythrocytic parasite life cycle. Exhaustive analysis of the P. falciparum genome revealed 14 potential genes encoding LRR-containing proteins, designated from PfLRR1 to PfLRR14. Molecular cloning and sequencing of the corresponding cDNA indicated that all PfLRRs contain 4-10 LRR motifs. Real-time quantitative PCR revealed that most of genes are highly expressed in late intraerythrocytic stages, including late trophozoites and schizonts. The ability of P. falciparum to express LRR-containing proteins will enable further investigations into the parasite interactome and create opportunities for discovering candidate drug targets.

Upper airway collapsibility, dilator muscle activation and resistance in sleep apnoea

The calibre of the upper airway is thought to be dependant upon its passive anatomy/collapsibility and the activation of pharyngeal dilator muscles. During awake periods, the more collapsible upper airway in obstructive sleep apnoea (OSA) increases the dilator muscle activity through a negative-pressure reflex. A direct correlation between the critical closing pressure (P(crit)), as a measure of anatomy/collapsability and electromyogram (EMG) activity of genioglossus EMG (GG-EMG) and tensor palatini EMG (TP-EMG), was hypothesised. The relationship between these indices and pharyngeal resistance (R(phar)) was also examined. The study involved eight males with a mean age of 48 (interquartile range 46-52) yrs with OSA, and an apnoea/hypopnoea index of 75 (65-101).hr(-1) on two nights breathing normally and on nasal continuous positive airway pressure (nCPAP). The P(crit )was measured during nonrapid eye movement sleep on nCPAP using brief, incremental reductions in mask pressure. GG-EMG and TP-EMG were measured breath-by-breath, awake, during sleep onset and on nCPAP. R(phar) was measured using airway pressures and flow. Wakeful GG-EMG, early sleep TP-EMG and the sleep decrement in TP-EMG were directly related to P(crit). Muscle activation was negatively correlated with R(phar) for TP-EMG awake and GG-EMG early in sleep. In conclusion these results confirm that dilator muscle activation is directly related to airway narrowing and reduces resistance across patients with obstructive sleep apnoea.

[Human pulmonary trichomonoses]

Colonization of human lungs by various Trichomonas species is a frequent occurrence, but is unknown to most physicians. At this site of infection, the parasite develops into an amoeboid form that renders it unrecognizable. For this reason it has been overlooked until recently. Morphological identification is not feasible under these conditions and molecular tools provide the only means of identification. The species involved are not restricted to Trichomonas tenax, a saprophyte of the mouth that is usually cited in the rare cases of pleuropulmonary trichomoniasis reported in the literature. The recent discovery of species previously unknown in humans raises further questions, including the zoonotic potential of these microorganisms and the existence of species of animal origin that have adapted to humans. Anaerobiosis in poorly ventilated alveolar lumen, rather than immunodepression, seems to be the factor that promotes proliferation of this parasite. The diagnosis of trichomoniasis and its treatment by specific drugs will make it possible to evaluate the pathogenicity of these parasites.

Persisting concentrating and second gas effects on oxygenation during N2O anaesthesia

Theoretical modelling predicts that the concentrating effect of nitrous oxide (N2O) uptake on alveolar oxygenation is a persisting phenomenon at typical levels of ventilation - perfusion (V/Q) inhomogeneity under anaesthesia. We sought clinical confirmation of this in 20 anaesthetised patients. Arterial oxygen pressure (P(aO2)) was measured after a minimum of 30 min of relaxant general anaesthesia with an inspired oxygen (F(I O2)) of 30%. Patients were randomly allocated to two groups. The intervention group had N2O introduced following baseline blood gas measurements, and the control group continued breathing an identical F(I O2) in nitrogen (N2). The primary outcome variable was change in P(aO2). Mean (SD) in P(aO2) was increased by 1.80 (1.80) kPa after receiving a mean of 47.5 min of N2O compared with baseline conditions breathing O2/N2 (p = 0.01). This change was significantly greater (p = 0.03) than that in the control group: + 0.09 (1.37) kPa, p = 0.83 and confirms the presence of significant persisting concentrating and second gas effects.

The tapeworm Ligula intestinalis (Cestoda: Pseudophyllidea) inhibits LH expression and puberty in its teleost host, Rutilus rutilus

The tapewormLigula intestinalisoccurs in the body cavity of its cyprinid second intermediate host, in this study the roachRutilus rutilus, and inhibits host gonadal development. The mechanism by which infected fish are prevented from reproducing is unknown. Comparison of parameters, such as body length and weight, and condition factor and age, between infected and uninfected individuals, indicated only minor effects of parasitism on growth and condition. In contrast, seasonal gonadal development, as observed in uninfected fish, did not occur in infected fish, and gonads remained small and blocked at the primary oocyte stage in female roach. As immature ovaries and testes are still present, the parasite is presumed to act upon the brain–pituitary–gonadal axis of the fish to inhibit further development of reproductive organs. We investigated theLigula/fish interaction at the level of the pituitary gland by determination of gonadotrophin (LH) content using a heterologous RIA for carp (Cyprinus carpio) LHβ subunit. The results indicated that the pituitary glands of infected roach contained approximately 50% less LH than non-infected fish. After the cloning and sequencing of roach LHβ subunit, we measured roach LHβ mRNA levels by real-time RT-PCR. A corresponding 50% reduction in LHβ mRNA pituitary levels was determined. These results reflect a significant and measurable effect of parasitism on the pituitary gland, and lend support to the hypothesis that excretory/secretory products released from the parasite interact with the brain–pituitary–gonadal axis of the fish host and thus inhibit gonadal development.

Molecular phylogenies of Blastocystis isolates from different hosts: implications for genetic diversity, identification of species, and zoonosis

Small-subunit (SSU) rRNA gene sequences were obtained by PCR from 12 Blastocystis isolates from humans, rats, and reptiles for which elongation factor 1alpha (EF-1alpha) gene sequences are already available. These new sequences were analyzed by the Bayesian method in a broad phylogeny including, for the first time, all Blastocystis sequences available in the databases. Phylogenetic trees identified seven well-resolved groups plus several discrete lineages that could represent newly defined clades. Comparative analysis of SSU rRNA- and EF-1alpha-based trees obtained by maximum-likelihood methods from a restricted sampling (13 isolates) revealed overall agreement between the two phylogenies. In spite of their morphological similarity, sequence divergence among Blastocystis isolates reflected considerable genetic diversity that could be correlated with the existence of potentially >/=12 different species within the genus. Based on this analysis and previous PCR-based genotype classification data, six of these major groups might consist of Blastocystis isolates from both humans and other animal hosts, confirming the low host specificity of Blastocystis. Our results also strongly suggest the existence of numerous zoonotic isolates with frequent animal-to-human and human-to-animal transmissions and of a large potential reservoir in animals for infections in humans.

Molecular phylogenies of Blastocystis isolates from different hosts: implications for genetic diversity, identification of species, and zoonosis

Small-subunit (SSU) rRNA gene sequences were obtained by PCR from 12 Blastocystis isolates from humans, rats, and reptiles for which elongation factor 1alpha (EF-1alpha) gene sequences are already available. These new sequences were analyzed by the Bayesian method in a broad phylogeny including, for the first time, all Blastocystis sequences available in the databases. Phylogenetic trees identified seven well-resolved groups plus several discrete lineages that could represent newly defined clades. Comparative analysis of SSU rRNA- and EF-1alpha-based trees obtained by maximum-likelihood methods from a restricted sampling (13 isolates) revealed overall agreement between the two phylogenies. In spite of their morphological similarity, sequence divergence among Blastocystis isolates reflected considerable genetic diversity that could be correlated with the existence of potentially >/=12 different species within the genus. Based on this analysis and previous PCR-based genotype classification data, six of these major groups might consist of Blastocystis isolates from both humans and other animal hosts, confirming the low host specificity of Blastocystis. Our results also strongly suggest the existence of numerous zoonotic isolates with frequent animal-to-human and human-to-animal transmissions and of a large potential reservoir in animals for infections in humans.

Use of individual polymorphism to validate potential functional markers: case of a candidate lectin (BgSel) differentially expressed in susceptible and resistant strains of Biomphalaria glabrata

BgSel has been identified in Biomphalaria glabrata as a candidate adhesion molecule exhibiting both an Ig-like domain and a carbohydrate recognition domain showing similarities with the l domain of C-type lectins. As susceptibility or resistance of B. glabrata to the trematode Echinostoma caproni correlates with a differential hemocytic adhesive behavior, we investigated the expression of BgSel in snails selected for their susceptibility or resistance. Semi-quantitative RT-PCR analysis of BgSel expression revealed that (i) BgSel expression level was high in susceptible snails and almost undetectable in resistant snails, and that (ii) exposure to the parasite did not affect the expression level of BgSel in either strain. In order to validate this apparent association between low levels of BgSel expression and resistance, we used Real-Time PCR to characterize the relative expression of BgSel in individual snails segregating for susceptibility/resistance. Results established that differential expression of BgSel represents a functional strain marker, but is not a marker of resistance/susceptibility. It is suggested that this correlative approach may be a rapid and efficient alternative to complete functional analyses, and may facilitate the validation of candidate transcripts potentially identified through the numerous differential analyses of animal transcriptomes.

Low molecular weight heparin for the prevention of hepatic veno-occlusive disease (VOD) after hematopoietic stem cell transplantation: a prospective phase II study

We evaluated 40 patients undergoing high-dose chemo/radiotherapy (HDCT) and hematopoietic stem cell transplantation (HSCT) (allogeneic (22), autologous (18)) to determine the safety and feasibility of administering low molecular weight heparin (LMWH) as hepatic veno-occlusive disease (VOD) prophylaxis. Patients received a once daily subcutaneous injection of dalteparin 2500 anti-Xa i.u. commencing the day prior to starting HDCT, and continuing until day +30 post HSCT or hospital discharge, whichever came first. Dosage adjustments were made for patients developing renal failure. All bleeding episodes were recorded and graded and VOD was diagnosed and graded according to Seattle criteria. At 100 days of follow-up, the overall survival and probability of regimen-related mortality were 85 and 15%, respectively. Nine patients developed VOD. The probability of developing VOD post allogeneic and autologous HSCT was 28% (95% CI, 6-45) and 17% (95% CI, 0-32), respectively. VOD was graded as moderate (n=8) and severe (n=1). VOD resolved in all cases except for one patient who died secondary to severe VOD and multiorgan failure. Clinically significant bleeding episodes occurred in three patients; 24 patients developed minor bleeding not requiring specific therapy. All bleeding episodes resolved. These results suggest that LMWH for VOD prophylaxis is safe with a low incidence of serious bleeding events. Whether it is superior to unfractionated heparin, however, is unknown and should be addressed within the context of a randomized controlled trial.

Rationale for including orofacial myofunctional therapy in university training programs

This article provides information on the need felt by speech-language pathologists for training in orofacial myofunctional phenomena. Results of a survey indicate 97.7% of respondents felt training is necessary, while only 7.9% felt their training was adequate. ASHA position statements regarding orofacial myology are reviewed. ASHA and IAOM suggested competencies are also included.

Impact of Medicare denials on noninvasive vascular diagnostic testing

PURPOSE

The purpose of this study was to evaluate the impact of Medicare coverage limitations and claim denials on noninvasive vascular diagnostic testing.

METHODS

All Medicare claims for noninvasive vascular diagnostic studies from January 1, 1999, to December 31, 1999, were identified from the hospital billing database according to Current Procedural Terminology codes for carotid artery duplex ultrasound scan, venous duplex ultrasound scan, and lower-extremity arterial Doppler scan. Reasons for Medicare denial of payment for these tests were reviewed and a cost analysis was performed.

RESULTS

During the 1-year period, there were 1096 noninvasive vascular diagnostic studies performed on Medicare patients. Of these 1096 tests, 176 (16.1%) were denied by Medicare (19.6% of 408 carotid duplex ultrasound scans, 16.8% of 345 venous duplex ultrasound scans, and 11.1% of 343 lower-extremity arterial Doppler scans). Of the noninvasive vascular tests denied by Medicare, an abnormal result was present in 72.5% of carotid duplex ultrasound scans, 32.8% of venous duplex ultrasound scans, and 78.9% of lower-extremity arterial Doppler scans. Overall, 88.1% of all initially denied claims (N = 176) were ultimately reimbursed by Medicare after resubmission, including 77.1% of the 118 claims denied based on compliance rules for "medical necessity."

CONCLUSION

Because of coverage limitations, Medicare denials of noninvasive vascular diagnostic tests can lead to potential uncompensated physician and hospital technical fees if denied claims are unrecognized. Vascular laboratories performing these tests need to review compliance with Medicare guidelines. Improvements may need to be made at both the provider and Medicare carrier levels in obtaining reimbursement for appropriately ordered noninvasive vascular diagnostic studies.

Cardiac and respiratory activity at arousal from sleep under controlled ventilation conditions

Arousal from sleep is associated with elevated cardiac and respiratory activity. It is unclear whether this occurs because of homeostatic mechanisms or a reflex activation response associated with arousal. Cardiorespiratory activity was measured during spontaneous arousals from sleep in subjects breathing passively on a ventilator. Under such conditions, homeostatic mechanisms are eliminated. Ventilation, end-tidal PCO2, mask pressure, diaphragmatic electromyograph, heart rate, and blood pressure were measured in four normal subjects under two conditions: assisted ventilation and a normal ventilation control condition. In the control condition, there was a normal, sleep-related fall in ventilation and rise in end-tidal PCO2. Subsequently, at an arousal, there was an increase in respiratory and cardiac activity. In the ventilator condition, a vigorous cardiorespiratory response to a spontaneous arousal from sleep remained. These results indicate that sleep-related respiratory stimuli are not necessary for the occurrence of elevated cardiorespiratory activity at an arousal from sleep and are consistent with the hypothesis that such activity is at least in part due to a reflex activation response.

Gait changes in children with spastic diplegia after selective dorsal rhizotomy

Twenty-six ambulatory children underwent preoperative and 1-year postoperative assessments after selective dorsal rhizotomy. These included spasticity, passive range of motion, tone, three-dimensional motion analysis, and electromyography. Independent and dependent ambulators were evaluated separately. A decrease in spasticity was found in all lower extremity muscle groups. An increase in passive range of motion was found only at the hip for both independent and dependent ambulators. Gait changes included increases in velocity and stride length in the independent ambulators. An improvement in hip extension during stance was found in the dependent ambulators only; however, an increase in knee extension and dorsiflexion in stance were seen in both groups. Selective dorsal rhizotomy improves both passive and dynamic range of motion in children with spastic diplegia.

Effect of age on sleep onset-related changes in respiratory pump and upper airway muscle function

In normal young men, there is an abrupt fall in ventilation (VE), a rise in upper airway resistance (UAR), and falls in the activities of the diaphragm (Di), intercostals (IC), genioglossus (GG), and tensor palatini (TP) at sleep onset. On waking, there is an abrupt increase in VE and fall in UAR and an increase in the activities of Di, IC, GG, and TP. The aim of this study was to determine whether these changes are age dependent. Nine men aged 20 to 25 yr were compared with nine men aged 42 to 67 yr. Airflow, UAR, Di, and IC surface electromyograms (EMGs) and the intramuscular EMGs of GG and TP were recorded. It was found that the falls in IC, GG, and TP at the transition from alpha to theta electroencephalogram (EEG) activity were significantly greater in the older than in the younger men (P < 0.05) and that the fall in Di was also greater, although this was only marginally significant (P = 0.15). The rise in GG at theta-to-alpha transitions was also greater in the older than in the younger men, and there was a trend for TP to be higher.

Molecular cloning of a putative alpha3-fucosyltransferase from Schistosoma mansoni

Alpha 3-fucosylation of protein or lipid substrates is an important component of the host/parasite interactions during schistosomiasis. In this process, alpha3-fucosyltransferases (alpha3-FucTs) are considered as key enzymes ensuring both parasite survival and adaptation in their (in)vertebrate hosts. In this paper, we report the molecular cloning of a putative alpha3-FucT from Schistosoma mansoni that we termed SmFucTA. The full-length SmFucTA encodes a typical transmembrane type II protein with a short cytoplasmic domain, a transmembrane segment and a long C-terminal catalytic domain. In this region, the GDP-fucose binding site is well conserved whereas the putative acceptor site displays sequence divergence compared to the corresponding region from vertebrate and invertebrate alpha3-FucTs. Southern blot analysis suggested that SmFucTA is present as several copies or has highly related counterparts in the S. mansoni genome. Northern blot revealed a single SmFucTA transcript at 2 kb in adult worms. Affinity purified antibodies directed against recombinant SmFucTA identified a 50 kDa native protein that localizes to the subtegumental and parenchymal regions of adult worms.

Accumulation of matrilysin (MMP-7) and macrophage metalloelastase (MMP-12) in actinic damage

Photodamage is characterized by degradation of collagen and accumulation of abnormal elastin in the superficial dermis and several matrix metalloproteinases have previously been implicated in this process. Using immunohistochemistry and in situ hybridization, we have studied the localization of two elastolytic matrix metalloproteinases, matrilysin (matrix metalloproteinase-7) and human macrophage metalloelastase (matrix metalloproteinase-12) in solar damage. Human macrophage metalloelastase protein was detected in the superficial dermis in areas of elastotic material. Matrix metalloproteinase-7 was seen in the mid-dermis in regions with less damaged elastic fibers and morphologically better preserved collagen as well as in a band-like pattern below basal keratinocytes in eight of 18 solar elastosis. In samples taken from healthy volunteers 3 d after repeated ultraviolet A or ultraviolet B photoprovocation, occasional immunopositive cells for human macrophage metalloelastase (stromal) or matrix metalloproteinase-7 (sweat gland epithelium) were detected. In samples taken 1 d after ultraviolet B exposure, however, basal keratinocytes were matrix metalloproteinase-7 immunopositive, explaining the linear immunostaining below basal keratinocytes noted particularly in ultraviolet B treated 3 d specimens. Upregulation of metalloelastase was also demonstrated in the skin of hairless mice after repeated ultraviolet exposure. In normal skin, no staining for human macrophage metalloelastase or matrix metalloproteinase-7 was observed in association with elastin. The amount of immunoreactivity for the substrates of matrix metalloproteinase-7, versican, and tenascin, was clearly increased in solar elastosis and photoprovocated skin; versican but not tenascin was detected in the same areas as matrix metalloproteinase-7. Our results suggest that both matrix metalloproteinase-7 and -12 may contribute to remodeling of elastotic areas in sun-damaged skin.

Impact of therapeutic interchange from pravastatin to lovastatin in a Veterans Affairs Medical Center

OBJECTIVE

To evaluate the impact of a therapeutic interchange from pravastatin to lovastatin on treatment outcomes, quality of life, patient satisfaction, and costs.

STUDY DESIGN

A prospective cohort study of 170 patients switched from pravastatin to lovastatin from September 1997 through November 1997.

PATIENTS AND METHODS

The therapeutic interchange program promoting lovastatin as the preferred agent went into effect June 2, 1997 after Merck & Co. was awarded the Veterans Health Administration national contract for 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors. Patients were switched to lovastatin by either their primary care physician during routine clinic visits or the pharmacist by mail. The following outcomes were measured before and after conversion to lovastatin: lipid values, liver function tests, National Cholesterol Education Program (NCEP) low-density cholesterol (LDL-C) goals achieved, quality of life (QOL) (measured by the Medical Outcomes Study 36-item short-form health survey [SF-36]), medication tolerance (measured with a global symptom survey), patient satisfaction, and cost-minimization analysis.

RESULTS

Lipid values and liver function test results were similar for pravastatin and lovastatin treatment. Forty percent of patients achieved NCEP LDL-C goals before and after formulary conversion. There were no significant differences between pravastatin and lovastatin in QOL, medication tolerance, and patient satisfaction. The projected cost savings from this therapeutic interchange was approximately $211,000 annually.

CONCLUSION

Therapeutic interchange from pravastatin to lovastatin resulted in substantial cost savings. QOL, patient satisfaction, and achievement of NCEP LDL-C goals were maintained.

UVB irradiation stimulates deposition of new elastic fibers by modified epithelial cells surrounding the hair follicles and sebaceous glands in mice

UVB irradiation stimulates the synthesis of elastin in the skin of humans and experimental animals. In this study we localized the site and the cells that are responsible for the synthesis of murine dermal elastic fibers. SKH-1 hairless mice were irradiated with UVB and the skin removed for light microscopy, electron microscopy, in situ hybridization, immunohistochemistry, and biochemical studies. In response to chronic low doses of UVB there was an initial moderate increase in tropoelastin mRNA in the papillary dermis. By contrast, there was a continuous marked elevation of collagen alpha1(I) message localizing to sites of inflammatory cell influx throughout the upper and lower dermis. After 25 wk of UV irradiation there was a 2-fold increase in skin elastin, yet total collagen remained unchanged. Serial desmosine analysis from en face sections indicated the increase in elastin content was due to dermal elastic fibers, an increase in the size and number of the dermal cysts, and an increase in subpanniculus elastic fibers. Elastin stains of en face sections suggested that the elastic fibers in the upper dermis were exclusively derived from cells lining the epithelial root sheath and sebaceous glands. In response to UV irradiation, the elastic fibers increased in number and size, wrapping around these structures and aligning in both directions as long fibers parallel to the body axis. Electron micrographs indicated that modified epithelial cells in close proximity to the flattened epithelial cells that encircled the root sheath and sebaceous glands were the source of the elastic fibers.

Activity of respiratory pump and upper airway muscles during sleep onset

Ventilation decreases at sleep onset. This change is initiated abruptly at alpha-theta electroencephalographic transitions. The aim of this study was to determine the contributions of reduced activity in respiratory pump muscles and upper airway dilator muscles to this change. Surface electromyograms over the diaphragm (Di) and intercostal muscles and fine-wire intramuscular electrodes in genioglossus (GG) and tensor palatini (TP) muscles were recorded in nine healthy young men. It was shown that phasic Di and both phasic and tonic TP activities were lower during theta than during alpha activity. Breath-by-breath analysis of the changes at alpha-theta transitions during the sleep-onset period showed a number of changes. At alpha-theta transitions, phasic activity of Di, intercostal, and GG muscles fell and rose again, and phasic and tonic activities of TP fell and remained at low levels during theta. With a state transition from theta to alpha, the phasic and tonic activities of the Di, GG, and TP increased dramatically. It is now clear that the fall in ventilation that occurs with sleep is related to a fall in activities of both upper airway dilator muscles and respiratory pump muscles.

Report of a new patient with transposition of the great arteries with deletion of 22q11.2

We report on a new patient with d-transposition of the great arteries who was found to have deletion of 22q11.2. He had minor facial anomalies, normal T- and B-cell subsets, and transient hypocalcemia. Similar to rare previous reports, our patient's extracardiac manifestations were relatively mild.

Duplex-directed vena caval filter placement: report of initial experience

BACKGROUND

Fluoroscopy, cost, and patient transport contribute to difficulties occasionally associated with the placement of vena caval filters. Follow-up data in the literature document the use of duplex ultrasonography in visualizing the filter and determining caval patency. Filter placement at the bedside or in the vascular laboratory with duplex ultrasonography may simplify this common procedure. We have attempted to define the feasibility of this method.

METHODS

Patients referred to the vascular surgery service for vena caval interruption were evaluated for ability to visualize the renal veins and inferior vena cava. Location of renal veins, maximum diameter of the vena cava, and presence or absence of thrombus were documented. If visualization was adequate, placement was performed at the bedside for patients in intensive care or in the vascular laboratory for nonmonitored patients. The initial 10 patients and subsequent patients in whom there was a question of adequate deployment underwent completion abdominal roentgenography. Patient follow-up was difficult. Duplex ultrasonography was used to assess migration, thrombus adherent to the filter, and vena caval patency. Patients in whom filter placement was prophylactic were given anticoagulants at the discretion of the primary physician. Inadequate visualization or vena caval size greater than 28 mm prompted fluoroscopic placement of the vena caval filter, because only Greenfield titanium filters were used in the study.

RESULTS

Twenty-nine patients were referred for vena caval interruption. Inadequate visualization occurred in four obese patients, and filters were placed by fluoroscopy. There were no vena caval measurements greater than 24 mm. Twenty-five filters were placed without technical difficulty. One filter tilted into the right renal vein, requiring a suprarenal filter placed by fluoroscopy. Patient retrieval for follow-up has been difficult, but by ultrasonography there has been one vena caval thrombosis and no major filter migration. There have been no reported pulmonary emboli other than the one patient with initial tilt of the filter.

CONCLUSIONS

Placement of vena caval filters is feasible with duplex ultrasonography. Visualization is the only limiting condition to placement and occurs rarely. Reducing the need for fluoroscopy, lowering costs, and not needing to transport the critically ill patient support the use of this system. Intravascular ultrasonography in selected patients may eliminate the need for fluoroscopic placement of vena caval filters.

Cost-effective method for bedside insertion of vena caval filters in trauma patients

BACKGROUND

The need for patient transport for inferior vena cava (IVC) filter placement impacts patient safety, comfort, charges, and nursing care. Bedside, ultrasound-guided IVC filter placement may offer an acceptable, cost-effective alternative.

METHODS

Prospective cohort study of 55 consecutive trauma patients requiring IVC filter placement. During a 13-month period (August of 1995-September of 1996), patients meeting criteria for IVC filter were evaluated. Complications were recorded, and the potential financial savings were determined.

RESULTS

Of 3,172 trauma admissions, 55 patients met IVC filter criteria and 49 patients had IVC filters placed under ultrasound guidance. In six patients (10.9%), ultrasound guided filter placement failed. There were four complications in four patients (8.2%). Over 13 months, charges were reduced by $69,800 when compared with radiology suite placement and $118,300 when compared with operative placement.

CONCLUSIONS

Ultrasound guided, bedside placement of IVC filters is a safe, cost-effective method of pulmonary embolism prophylaxis in select trauma patients.

Developmental skills of children with spastic diplegia: functional and qualitative changes after selective dorsal rhizotomy

OBJECTIVE

This study examined changes in muscle tone, passive range of motion, stability, and mobility in developmental skills at 6 months and 1 year after selective dorsal rhizotomy (SDR).

DESIGN

Prospective outcome study of a consecutive sample.

SETTING

Private children's hospital.

PATIENTS

Twenty-six children with spastic diplegia: 13 independent and 13 dependent ambulators (assistive devices).

RESULTS

A decrease in spasticity was seen at 6 months after SDR, with no further decrease at 1 year. Increases in passive range of motion of the hip and ankle were seen at 6 months after SDR. The ability to assume and maintain developmental positions with improved alignment and stability was seen more frequently at 6 months after SDR, whereas an improvement in the ability to perform transitional movements was seen more frequently at 1 year after SDR.

CONCLUSION

SDR decreases spasticity and increases lower extremity range of motion in children with spastic diplegia and appears to be associated with the ability to assume a greater variety of developmental positions with improved alignment, thus greater stability. Improvements in the ability to perform difficult transitional movements at 1 year after SDR are most likely the result of the combined effect of maturation, SDR, and intensive therapeutic intervention.