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An implantable joint-angle transducer (IJAT) was implemented to provide command-control information from the wrist for functional neuromuscular stimulation (FNS) neuroprostheses. The IJAT uses the Hall effect to sense joint angle. The objectives of this study were to evaluate (1) chronic functionality, (2) safety and biocompatibility, (3) repeatability of the implantation procedure, and (4) clinical feasibility. Accelerated bench testing projected an operating period of over 50 years. In chronic animal experiments, stable output was obtained from three of four IJATs for periods of 10 to 19 months. Histology revealed acceptable osseointegration of the implant. The device has been implanted in human subjects for over 2 years and provides an excellent control signal for hand grasp. We conclude that this device is safe and effective for chronic human use as a control input for an implanted hand neuroprosthesis. [ABSTRACT FROM AUTHOR]

Aminopeptidase N (APN/CD13) is a zinc-dependent M1 aminopeptidase that contributes to cancer progression by promoting angiogenesis, metastasis, and tumor invasion. We have previously identified hydroxamic acid-containing analogues that are potent inhibitors of the APN homologue from the malarial parasite Plasmodium falciparum M1 aminopeptidase ( Pf A-M1). Herein, we describe the rationale that underpins the repurposing of Pf A-M1 inhibitors as novel APN inhibitors. A series of novel hydroxamic acid analogues were developed using a structure-based design approach and evaluated their inhibition activities against APN. N -(2-(Hydroxyamino)-2-oxo-1-(3',4',5'-trifluoro-[1,1'-biphenyl]-4-yl)ethyl)-4-(methylsulfonamido)benzamide ( 6ad ) proved to be an extremely potent inhibitor of APN activity in vitro, selective against other zinc-dependent enzymes such as matrix metalloproteases, and possessed limited cytotoxicity against Ad293 cells and favorable physicochemical and metabolic stability properties. The combined results indicate that compound 6ad may be a useful lead for the development of anticancer agents.

Background.: Bloodstream infection (BSI) to due vancomycin-resistant Enterococcus (VRE) is an important complication of hematologic malignancy. Determining when to use empiric anti-VRE antibiotic therapy in this population remains a clinical challenge., Methods.: A single-center cohort representing 664 admissions for induction or hematopoietic stem-cell transplant (HSCT) from 2006 to 2014 was selected. We derived a prediction score using risk factors for VRE BSI and evaluated the model's predictive performance by calculating it for each of 16232 BSI at-risk inpatient days., Results.: VRE BSI incidence was 6.5% of admissions (2.7 VRE BSI per 1000 BSI at-risk days). Adjusted 1-year mortality and length of stay were significantly higher in patients with VRE BSI. VRE colonization (adjusted odds ratio [aOR] = 8.4; 95% confidence interval [CI] = 3.4-20.6; P < .0001), renal insufficiency (aOR = 2.4; 95% CI = 1.0-5.8; P = .046), aminoglycoside use (aOR = 4.7; 95% CI = 2.2-9.8; P < .0001), and antianaerobic antibiotic use (aOR = 2.8; 95% CI = 1.3-5.8; P = .007) correlated most closely with VRE BSI. A prediction model with optimal performance included these factors plus gastrointestinal disturbance, severe neutropenia, and prior beta-lactam antibiotic use. The score effectively risk-stratified patients (area under the receiver operating curve = 0.84; 95% CI = 0.79-0.89). At a threshold of ≥5 points, per day probability of VRE BSI was increased nearly 4-fold., Conclusions.: This novel predictive score is based on risk factors reflecting a plausible pathophysiological model for VRE BSI in patients with hematological malignancy. Integrating VRE colonization status with risk factors for developing BSI is a promising method of guiding rational use of empiric anti-VRE antimicrobial therapy in patients with hematological malignancy. Validation of this novel predictive score is needed to confirm clinical utility., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com)

Recurrent Clostridium difficile infection (CDI) is a consequence of intestinal dysbiosis and is particularly common following hematopoietic stem cell transplantation (HSCT). Fecal microbiota transplantation (FMT) is an effective method of treating CDI by correcting intestinal dysbiosis by passive transfer of healthy donor microflora. FMT has not been widely used in immunocompromised patients, including HSCT recipients, owing to concern for donor-derived infection. Here, we describe initial results of an FMT program for CDI at a US HSCT center. Seven HSCT recipients underwent FMT between February 2015 and February 2016. Mean time post HSCT was 635 days (25-75 interquartile range [IQR] 38-791). Five of the patients (71.4%) were on immunosuppressive therapy at FMT; 4 had required long-term suppressive oral vancomycin therapy because of immediate recurrence after antibiotic cessation. Stool donors underwent comprehensive health and behavioral screening and laboratory testing of serum and stool for 32 potential pathogens. FMT was administered via the naso-jejunal route in 6 of the 7 patients. Mean follow-up was 265 days (IQR 51-288). Minor post-FMT adverse effects included self-limited bloating and urgency. One patient was suspected of having post-FMT small intestinal bacterial overgrowth. No serious adverse events were noted and all-cause mortality was 0%. Six of 7 (85.7%) patients had no recurrence; 1 patient recurred at day 156 post FMT after taking an oral antibiotic and required repeat FMT, after which no recurrence has occurred. Diarrhea was improved in all patients and 1 patient with gastrointestinal graft-versus-host disease was able to taper off systemic immunosuppression after FMT. With careful donor selection and laboratory screening, FMT appears to be a safe and effective therapy for CDI in HSCT patients and may confer additional benefits. Larger studies are necessary to confirm safety and efficacy and explore other possible effects., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The use of arginine isosteres is a known strategy to overcome poor membrane permeability commonly associated with peptides or peptidomimetics that possess this highly polar amino acid. Here, we apply this strategy to peptidomimetics that are potent inhibitors of the malarial protease, plasmepsin V, with the aim of enhancing their activity against Plasmodium parasites, and exploring the structure-activity relationship of the P3 arginine within the S3 pocket of plasmepsin V. Of the arginine isosteres trialled in the P3 position, we discovered that canavanine was the ideal and that this peptidomimetic potently inhibits plasmepsin V, efficiently blocks protein export and inhibits parasite growth. Structure studies of the peptidomimetics bound to plasmepsin V provided insight into the structural basis for the enzyme activity observed in vitro and provides further evidence why plasmepsin V is highly sensitive to substrate modification., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Mycobacterium tuberculosis (Mtb) Cmr (Rv1675c) is a CRP/FNR family transcription factor known to be responsive to cAMP levels and during macrophage infections. However, Cmr's DNA binding properties, cellular targets and overall role in tuberculosis (TB) complex bacteria have not been characterized. In this study, we used experimental and computational approaches to characterize Cmr's DNA binding properties and identify a putative regulon. Cmr binds a 16-bp palindromic site that includes four highly conserved nucleotides that are required for DNA binding. A total of 368 binding sites, distributed in clusters among ~200 binding regions throughout the Mycobacterium bovis BCG genome, were identified using ChIP-seq. One of the most enriched Cmr binding sites was located upstream of the cmr promoter, and we demonstrated that expression of cmr is autoregulated. cAMP affected Cmr binding at a subset of DNA loci in vivo and in vitro, including multiple sites adjacent to members of the DosR (DevR) dormancy regulon. Our findings of cooperative binding of Cmr to these DNA regions and the regulation by Cmr of the DosR-regulated virulence gene Rv2623 demonstrate the complexity of Cmr-mediated gene regulation and suggest a role for Cmr in the biology of persistent TB infection., (© The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Plasmepsin V, an essential aspartyl protease of malaria parasites, has a key role in the export of effector proteins to parasite-infected erythrocytes. Consequently, it is an important drug target for the two most virulent malaria parasites of humans, Plasmodium falciparum and Plasmodium vivax. We developed a potent inhibitor of plasmepsin V, called WEHI-842, which directly mimics the Plasmodium export element (PEXEL). WEHI-842 inhibits recombinant plasmepsin V with a half-maximal inhibitory concentration of 0.2 nM, efficiently blocks protein export and inhibits parasite growth. We obtained the structure of P. vivax plasmepsin V in complex with WEHI-842 to 2.4-Å resolution, which provides an explanation for the strict requirements for substrate and inhibitor binding. The structure characterizes both a plant-like fold and a malaria-specific helix-turn-helix motif that are likely to be important in cleavage of effector substrates for export.

Following erythrocyte invasion, malaria parasites export a catalogue of remodeling proteins into the infected cell that enable parasite development in the human host. Export is dependent on the activity of the aspartyl protease, plasmepsin V (PMV), which cleaves proteins within the Plasmodium export element (PEXEL; RxL↓xE/Q/D) in the parasite's endoplasmic reticulum. Here, we generated transition state mimetics of the native PEXEL substrate that potently inhibit PMV isolated from Plasmodium falciparum and Plasmodium vivax. Through optimization, we identified that the activity of the mimetics was completely dependent on the presence of P1 Leu and P3 Arg. Treatment of P. falciparum-infected erythrocytes with a set of optimized mimetics impaired PEXEL processing and killed the parasites. The striking effect of the compounds provides a clearer understanding of the accessibility of the PMV active site and reaffirms the enzyme as an attractive target for the design of future antimalarials.

A whole-organism screen of approximately 87000 compounds against Trypanosoma brucei brucei identified a number of promising compounds for medicinal chemistry optimization. One of these classes of compounds we termed the pyridyl benzamides. While the initial hit had an IC50 of 12 μM, it was small enough to be attractive for further optimization, and we utilized three parallel approaches to develop the structure-activity relationships. We determined that the physicochemical properties for this class are generally favorable with particular positions identified that appear to block metabolism when substituted and others that modulate solubility. Our most active compound is 79, which has an IC50 of 0.045 μM against the human pathogenic strain Trypanosoma brucei rhodesiense and is more than 4000 times less active against the mammalian L6 cell line.

The malaria parasite Plasmodium falciparum exports several hundred proteins into the infected erythrocyte that are involved in cellular remodeling and severe virulence. The export mechanism involves the Plasmodium export element (PEXEL), which is a cleavage site for the parasite protease, Plasmepsin V (PMV). The PMV gene is refractory to deletion, suggesting it is essential, but definitive proof is lacking. Here, we generated a PEXEL-mimetic inhibitor that potently blocks the activity of PMV isolated from P. falciparum and Plasmodium vivax. Assessment of PMV activity in P. falciparum revealed PEXEL cleavage occurs cotranslationaly, similar to signal peptidase. Treatment of P. falciparum-infected erythrocytes with the inhibitor caused dose-dependent inhibition of PEXEL processing as well as protein export, including impaired display of the major virulence adhesin, PfEMP1, on the erythrocyte surface, and cytoadherence. The inhibitor killed parasites at the trophozoite stage and knockdown of PMV enhanced sensitivity to the inhibitor, while overexpression of PMV increased resistance. This provides the first direct evidence that PMV activity is essential for protein export in Plasmodium spp. and for parasite survival in human erythrocytes and validates PMV as an antimalarial drug target., Competing Interests: The authors have declared that no competing interests exist.

The incidence of congenital diaphragmatic hernia (CDH) is about 4.8/10,000 live births. Its typical clinical presentation is respiratory distress occurring immediately after birth or in the first few hours or days of a child's life. It is characterized by a high mortality rate. Exceptionally, CDH can occur at an older age, its symptoms then frequently reflecting gastrointestinal obstruction or mild respiratory symptoms. In such cases CDH presents a far more complex diagnostic problem. The paper presents the cases of two girls without typical symptomatology, aged 5.5 and 10 years, in whom CDH was detected incidentally upon thorough physical examination and chest x-rays. Further radiographic evaluation, which included barium contrast study and spiral computed tomography, confirmed the suspicion of a left-sided posterolateral diaphragmatic hernia with associated intestinal malrotation. Surgical intervention conclusively confirmed a diaphragmatic defect at the site of Bochdalek's foramen in both cases. The vital capacity of the older girl, which was low before the surgery (VC 1.66 L; 69% of predicted), was significantly increased a month after the surgical treatment (VC 2.25 L; 92% of predicted). The generally expressed view that the clinical onset of CDH is rare after the neonatal period seems to be erroneous. Some papers report on the clinical presentation of CDH after the neonatal period in as many as 13%-14% of infants and young children suffering from CDH. Infants and young children with a delayed clinical occurrence of CDH can present with respiratory or gastrointestinal symptomatology. Children presenting with gastrointestinal symptoms have been shown to be significantly older than those presenting with respiratory symptoms. In older children and adolescents, the symptoms and signs of CDH, which include acute hernial incarceration, nausea, recurrent vomiting, diarrhea, obstipation, acute gastric dilatation, subcostal pain, failure to thrive and recurrent chest infections, habitually present a significant diagnostic problem. Diagnostic errors are mainly due to the fact that the possibility of CDH in that age is totally neglected. The most recurrent diagnostic misinterpretations in such cases are pneumonia or massive pleuropneumonia, empyema, pneumothorax, lung cysts and bullae, and gastric volvulus. Thus, whenever a child presents with uncommon respiratory or gastrointestinal symptoms and an anomalous chest x-ray, a differential diagnosis of CDH should be considered. Otherwise, an accurate diagnosis in both young and older children will most probably be only reached at autopsy. In conclusion, the presented cases corroborate the finding that CDH in older children may present with scarce symptoms, mostly gastrointestinal, or may be altogether asymptomatic and unrecognized until as late as adolescence. However, when a diagnosis of CDH has been established, albeit asymptomatic, it must be promptly treated surgically in order to prevent complications, such as strangulation or bowel perforation, and thus avert a potentially fatal outcome. The size itself of the herniac foramen is unlikely to be a determining factor at the time of clinical presentation of CDH. Surgical occlusion of CDH may in older children result in an improved vital capacity, as such cases are rarely associated with major pulmonary hypoplasia. Complications resulting from surgical treatment of CDH in older children are more likely to occur in the gastrointestinal system, as a consequence of the associated bowel malrotation and inadequate bowel fixation. Finally, these two cases corroborate the diagnostic value of accurate history taking and thorough physical examination.

The urachus is an embryonic structure that persists after birth in some individuals and can cause various problems. We report a case of an inflamed urachal cyst filled with a thick yellow fluid and several calculi in a woman with a 1-month history of dysuria. Physical examination revealed a fist-sized tumor located infraumbically in the midline. The patient's erythrocyte sedimentation rate was elevated; the results of all other routine laboratory studies were normal. Sonography showed a regularly shaped, ovoid, hypoechoic cystic area in the abdominal wall measuring 8 x 4 x 3 cm and containing several hyperechoic masses associated with acoustic shadowing. The wall of the cyst was inhomogeneous, and a thin hypoechoic linear tract linked the superior aspect of the mass to the umbilicus. The results of excretory urography, voiding cystography, and cystoscopy excluded an abnormality of the urinary system. A urachal cyst was diagnosed, and the mass was surgically removed. The surgical specimen was sent for histopathologic analysis, which confirmed the diagnosis., (Copyright 2002 Wiley Periodicals, Inc.)

An implantable joint angle transducer (IJAT) was developed to provide command-control and feedback-control information for chronic use with functional neuromuscular stimulation (FNS) neuroprostheses. The IJAT uses Hall effect sensors to transduce joint angle. A titanium encapsulated array of Hall effect sensors and support circuitry is surgically implanted in one bone, and a similarly encapsulated permanent magnet in an opposing bone, across a joint. The IJAT provides consistent, reliable, high quality signals that reflect joint movement from midsized two-degree-of-freedom joints. IJAT's were implanted using a chronic in vivo dog model to demonstrate the feasibility of implantation and periodic measurement techniques, and to validate modeling techniques used for prediction of function and calibration. The flexion resolution ranged from 0.4 to 3.0 degrees over a range of 115 degrees. The maximum deviation from a linear response was 9 degrees. The resolution and linearity depend on several transducer and joint geometry parameters, and can be predicted prior to implantation and calibrated after implantation. The results of this study 1) defined the most appropriate hermetic capsule designs for the IJAT sensor and magnet, 2) defined the best orientation of the magnetic field to optimize device function, 3) provided a computer model of the IJAT to aid in placement, calibration, and evaluation of the device, 4) verified the surgical techniques used to implant the device, and 5) verified the long-term functionality and the biocompatibility of the device.

An implantable integrated stimulator and telemetry system has been developed. The system is capable of fulfilling the stimulus and telemetry needs of advanced functional neuromuscular stimulation (FNS) applications requiring multiple channels of stimulation and multiple channels of sensor or biopotential sensing. This system provides a command control structure, an inductive radio frequency link providing power to the implant device as well as two-way transcutaneous communication, an ASIC for decoding the command and for providing functional control within the implant, and modular circuitry providing the application specific implant functions. Biocompatible hermetic packaging, lead systems, and in-line connectors suitable for long-term implantation, provide encapsulation for the circuitry and access to the electrodes and sensors used in the application. The first implant configuration realized from this modular system is targeted for clinical implementation in persons with tetraplegia at the C6 level for restoration of hand function, using wrist position as the command control source. The implant device realized has ten channels of stimulation and telemetry used to control and sense a joint angle transducer implanted in the radio-carpal joint of the wrist. A prototype device has been fabricated and is undergoing testing in an animal.

In an attempt to determine whether the clinical data obtained by primary survey may be used as early outcome predictors in children who had sustained head trauma, children aged 0-14 with clinical diagnoses of coma, contusion, comotio, skull fracture or a combination of these diagnoses or who had been hospitalized for at least 3 days, between 1987 and 1990, were reviewed retrospectively. The outcome was defined by the clinical condition of children 6 months following head trauma using a Glasgow outcome scale (GOS), and was classified: good (good recovery and moderate disability) and poor (severe disability, persistent vegetative state, death). Of 70 children with trauma, 43 patients (61.4%) were separated by this method. The pupillary appearance and reactivity, Glasgow coma scale (GCS) and motor response graded by GCS were compared with the outcome. The analysis demonstrated that the early significant predictors of outcome of head trauma are the pupillary appearance and reactivity as well as Glasgow coma scale. Motor response graded by GCS did not achieve statistical significance (z = 1.5, P > 0.05) as a predictor of outcome. In this analysis, we have graded motor response according to the GCS criteria, thus it is not excluded that the use of different criteria could demonstrate the importance of motor response as an outcome predictor. In order to ascertain the significance of predictors in early outcome prognosis of head trauma, a relative risk for poor outcome was calculated. Our results showed that the significant predictors in descending order of preference are: pupillary reactivity, pupillary appearance and GCS.(ABSTRACT TRUNCATED AT 250 WORDS)

The therapeutic effect of aminophylline in children having severe asthmatic attacks with a special emphasis on an appropriate dose, adequate administration and measurement of serum aminophylline concentrations is presented. The study group consisted of 24 patients with severe asthmatic attacks. The patients were assigned to three groups according to the dosage of aminophylline administered. Patients in Group 1 received a dose of 7 mg/kg body weight, those in Group 2 5 mg/kg body weight and those in Group 3 (previously treated with theophylline) 4 mg/kg body weight. For each patient, clinical and laboratory parameters were followed. The results demonstrated that adequate therapeutic response and optimal serum theophylline concentrations were achieved only in Group 1. Patients in which lower doses of aminophylline were employed (Group 2 and Group 3) showed neither the adequate therapeutic response not did achieve the adequate serum theophylline concentrations, and administration of aminophylline had to be repeated. In the majority of patients, mild hyperglicemia was noticed. The mechanism and the sequence of events how it occurred was not determined. In conclusion, this data show that aminophylline, if administered in an adequate dose, is a drug of choice in the treatment of children with severe asthmatic attacks.

The study presents the results of a long term investigation of 60 epileptic children with Rolandic (centrotemporal) spikes in EEG. The results could be summarized as follows: the Rolandic epilepsy is relatively frequent entity (13.4% of the total number of epileptic children). The age span was from 3--13 years, with a peak of age incidence between the 7th and 8th year of life. More than half of children had nocturnal fits only. From the clinical point of view 60% of children had generalized crises, and the remaining 40% had partial attacks corresponding to the functional organization of the Rolandic cortical area. The evolution of the Rolandic epilepsy in childhood is favourable. More than 50% didn't have more attacks after the introduction of antiepileptic therapy, and 3/4 of them could be classified as practically cured after an long-term follow-up (criterion: an attack-free period of at least 5 years. Finally, in more than 80% of cases after three years of follow-up the spikes have disappeared from the EEG tracings which were completely normal.