Robust and Transparent Silver Oxide Coating Fabricated at Room Temperature Kills Clostridioides difficile Spores, MRSA, and Pseudomonas aeruginosa

Antimicrobial coatings can inhibit the transmission of infectious diseases when they provide a quick kill that is achieved long after the coating application. Here, we describe the fabrication and testing of a glass coating containing Ag2O microparticles that was prepared from sodium silicate at room temperature. The half-lives of both methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa on this coating are only 2-4 min. The half-life of Clostridioides difficile spores is about 9-12 min, which is extremely short for a spore. Additional tests on MRSA demonstrate that the coating retains its antimicrobial activity after abrasion and that an increased loading of Ag2O leads to a shorter half-life. This coating combines the properties of optical transparency, robustness, fast kill, and room temperature preparation that are highly desirable for an antimicrobial coating.

Premise Plumbing Pipe Materials and In-Building Disinfectants Shape the Potential for Proliferation of Pathogens and Antibiotic Resistance Genes

In-building disinfectants are commonly applied to control the growth of pathogens in plumbing, particularly in facilities such as hospitals that house vulnerable populations. However, their application has not been well optimized, especially with respect to interactive effects with pipe materials and potential unintended effects, such as enrichment of antibiotic resistance genes (ARGs) across the microbial community. Here, we used triplicate convectively mixed pipe reactors consisting of three pipe materials (PVC, copper, and iron) for replicated simulation of the distal reaches of premise plumbing and evaluated the effects of incrementally increased doses of chlorine, chloramine, chlorine dioxide, and copper-silver disinfectants. We used shotgun metagenomic sequencing to characterize the resulting succession of the corresponding microbiomes over the course of 37 weeks. We found that both disinfectants and pipe material affected ARG and microbial community taxonomic composition both independently and interactively. Water quality and total bacterial numbers were not found to be predictive of pathogenic species markers. One result of particular concern was the tendency of disinfectants, especially monochloramine, to enrich ARGs. Metagenome assembly indicated that many ARGs were enriched specifically among the pathogenic species. Functional gene analysis was indicative of a response of the microbes to oxidative stress, which is known to co/cross-select for antibiotic resistance. These findings emphasize the need for a holistic evaluation of pathogen control strategies for plumbing.

Antimicrobial mechanism of cuprous oxide (Cu2O) coatings

Some very effective antimicrobial coatings exploit copper or cuprous oxide (Cu2O) as the active agent. The aim of this study is to determine which species is the active antimicrobial - dissolved ions, the Cu2O solid, or reactive oxygen species. Copper ions were leached from Cu2O into various solutions and the leachate tested for both dissolved copper and the efficacy in killing Pseudomonas aeruginosa. The concentration of copper species leached from Cu2O into aqueous solution varied greatly with the composition of the aqueous solution. For a range of solution buffers, killing of P. aeruginosa was highly correlated with the concentration of copper in the leachate. Further, 10 µL bacterial suspension droplets were placed on Cu2O coatings, with or without a polymer barrier layer, and tested for bacterial kill. Killing occurred without contact between bacterium and solid, demonstrating that contact with Cu2O is not necessary. We therefore conclude that soluble copper species are the antimicrobial agent, and that the most potent species is Cu+. The solid quickly raises and sustains the concentration of soluble copper species near the bacterium. Killing via soluble copper ions rather than contact should allow copper coatings to kill bacteria even when fouled, which is an important practical consideration.

Influence of pipe materials on in-building disinfection of P. aeruginosa and A. baumannii in simulated hot water plumbing

A framework is needed to account for interactive effects of plumbing materials and disinfectants on opportunistic pathogens (OPs) in building water systems. Here we evaluated free chlorine, monochloramine, chlorine dioxide, and copper-silver ionization (CSI) for controlling Pseudomonas aeruginosa and Acinetobacter baumannii as two representative OPs that colonize hot water plumbing, in tests using polyvinylchloride (PVC), copper-PVC, and iron-PVC convectively-mixed pipe reactors (CMPRs). Pipe materials vulnerable to corrosion (i.e., iron and copper) altered the pH, dissolved oxygen, and disinfectant levels in a manner that influenced growth trends of the two OPs and total bacteria. P. aeruginosa grew well in PVC CMPRs, poorly in iron-PVC CMPRs, and was best controlled by CSI disinfection, whereas A. baumannii showed the opposite trend for pipe material and was better controlled by chlorine and chlorine dioxide. Various scenarios were identified in which pipe material and disinfectant can interact to either hinder or accelerate growth of OPs, illustrating the difficulties of controlling OPs in portions of plumbing systems experiencing warm, stagnant water.

Facile Implementation of Antimicrobial Coatings through Adhesive Films (Wraps) Demonstrated with Cuprous Oxide Coatings

Antimicrobial coatings have a finite lifetime because of wear, depletion of the active ingredient, or surface contamination that produces a barrier between the pathogen and the active ingredient. The limited lifetime means that facile replacement is important. Here, we describe a generic method for rapidly applying and reapplying antimicrobial coatings to common-touch surfaces. The method is to deposit an antimicrobial coating on a generic adhesive film (wrap), and then to attach that modified wrap to the common-touch surface. In this scenario, the adhesion of the wrap and antimicrobial efficacy are separated and can be optimized independently. We demonstrate the fabrication of two antimicrobial wraps, both using cuprous oxide (Cu₂O) as the active ingredient. The first uses polyurethane (PU) as the polymeric binder and the second uses polydopamine (PDA). Our antimicrobial PU/Cu₂O and PDA/Cu₂O wraps, respectively, kill >99.98% and >99.82% of the human pathogen, P. aeruginosa, in only 10 min, and each of them kill >99.99% of the bacterium in 20 min. These antimicrobial wraps can be removed and replaced on the same object in <1 min with no tools. Wraps are already frequently used by consumers to coat drawers or cars for aesthetic or protective purposes.

Porous Antimicrobial Coatings for Killing Microbes within Minutes

Antimicrobial coatings can be used to reduce the transmission of infectious agents that are spread by contact. An effective coating should kill microbes in the time between users, which is sometimes minutes or less. Fast killing requires fast transport, and our proposed method of fast transport is a porous coating where the contaminated liquid imbibes (infiltrates) into the pores to achieve rapid contact with active material inside the pores. We test the hypothesis that a porous antimicrobial coating will enable faster inactivation of microorganisms than a planar coating of the same material. We use hydrophilic pores with dimensions of 5-100 μm such that liquid droplets imbibe in seconds, and from there transport distances and times are short, defined by the pore size rather than the droplet size. Our coating has two levels of structure: (A) a porous scaffold and (B) an antimicrobial coating within the pore structure containing the active ingredient. Two scaffolds are studied: stainless steel and poly(methyl methacrylate) (PMMA). The active ingredient is electrolessly deposited copper. To enhance adhesion and growth of copper, a layer of polydopamine (PDA) is deposited on the scaffold prior to deposition of the copper. This porous copper coating kills 99.84% of Pseudomonas aeruginosa within 3 min, which is equivalent to a half-life of 27 s. In contrast, the same layer of PDA/copper on a nonporous coating kills 79.65% in the same time frame, consistent with the hypothesis that the killing rate is increased by the addition of porosity. Using the porous PMMA scaffold, the porous antimicrobial coating kills >99.99% P. aeruginosa in 5 min, which is equivalent to a half-life of 21 s. The higher rate of kill on the porous antimicrobial solid is appropriate for hindering the spread of infectious agents on common-use objects.

Desiccation-Tolerance of Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium chimaera, Mycobacterium abscessus and Mycobacterium chelonae

Desiccation-tolerance of cells of four strains of Mycobacterium chimaera and individual strains of Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium abscessus, and Mycobacterium chelonae were measured by two methods. The survival of water-acclimated cells both in filter paper and on the surface of stainless-steel coupons were measured. In filter paper at 40% relative humidity at 25 °C, survival of patient isolates of M. avium and M. chimaera cells was 28% and 34% after 21 days of incubation, whereas it was 100% for the Sorin 3T isolate of M. chimaera. On stainless-steel biofilms after 42 days of incubation at 40% relative humidity at 25 °C, survival of water-acclimated cells of M. intracellulare was above 100%, while M. chelonae cells did not survive beyond 21 days, and survival of water-acclimated cells of M. avium and M. abscessus was 18% and 14%, respectively. On stainless-steel coupons, survival of patient and Sorin 3T isolates of M. chimaera was quite similar, specifically between 14% and 28% survival, after 42 days of incubation at 40% relative humidity at 25 °C. The experiments would support the hypothesis that some nontuberculous mycobacterial species are relatively desiccation-tolerant, whereas others are not. Further, long-term survival of the two M. chimaera strains is consistent with the presence of that species in Sorin 3T heater-coolers shipped throughout the world.

Transparent Anti-SARS-CoV-2 and Antibacterial Silver Oxide Coatings

Transparent antimicrobial coatings can maintain the aesthetic appeal of surfaces and the functionality of a touch-screen while adding the benefit of reducing disease transmission. We fabricated an antimicrobial coating of silver oxide particles in a silicate matrix on glass. The matrix was grown by a modified Stöber sol-gel process with vapor-phase water and ammonia. A coating on glass with 2.4 mg of Ag2O per mm2 caused a reduction of 99.3% of SARS-CoV-2 and >99.5% of Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus compared to the uncoated glass after 1 h. We envisage that screen protectors with transparent antimicrobial coatings will find particular application to communal touch-screens, such as in supermarkets and other check-out or check-in facilities where a number of individuals utilize the same touch-screen in a short interval.

Transparent and Sprayable Surface Coatings that Kill Drug-Resistant Bacteria Within Minutes and Inactivate SARS-CoV-2 Virus

Antimicrobial coatings are one method to reduce the spread of microbial diseases. Transparent coatings preserve the visual properties of surfaces and are strictly necessary for applications such as antimicrobial cell phone screens. This work describes transparent coatings that inactivate microbes within minutes. The coatings are based on a polydopamine (PDA) adhesive, which has the useful property that the monomer can be sprayed, and then the monomer polymerizes in a conformal film at room temperature. Two coatings are described (1) a coating where PDA is deposited first and then a thin layer of copper is grown on the PDA by electroless deposition (PDA/Cu) and (2) a coating where a suspension of Cu2O particles in a PDA solution is deposited in a single step (PDA/Cu2O). In the second coating, PDA menisci bind Cu2O particles to the solid surface. Both coatings are transparent and are highly efficient in inactivating microbes. PDA/Cu kills >99.99% of Pseudomonas aeruginosa and 99.18% of methicillin-resistant Staphylococcus aureus (MRSA) in only 10 min and inactivates 99.98% of SARS-CoV-2 virus in 1 h. PDA/Cu2O kills 99.94% of P. aeruginosa and 96.82% of MRSA within 10 min and inactivates 99.88% of SARS-CoV-2 in 1 h.

Weekly paclitaxel, carboplatin, cetuximab, and cetuximab, docetaxel, cisplatin, and fluorouracil, followed by local therapy in previously untreated, locally advanced head and neck squamous cell carcinoma

BACKGROUND

The survival advantage of induction chemotherapy (IC) followed by locoregional treatment is controversial in locally advanced head and neck squamous cell carcinoma (LAHNSCC). We previously showed feasibility and safety of cetuximab-based IC (paclitaxel/carboplatin/cetuximab-PCC, and docetaxel/cisplatin/5-fluorouracil/cetuximab-C-TPF) followed by local therapy in LAHNSCC. The primary end point of this phase II clinical trial with randomization to PCC and C-TPF followed by combined local therapy in patients with LAHNSCC stratified by human papillomavirus (HPV) status and T-stage was 2-year progression-free survival (PFS) compared with historical control.

PATIENTS AND METHODS

Eligible patients were ≥18 years with squamous cell carcinoma of the oropharynx, oral cavity, nasopharynx, hypopharynx, or larynx with measurable stage IV (T0-4N2b-2c/3M0) and known HPV by p16 status. Stratification was by HPV and T-stage into one of the two risk groups: (i) low-risk: HPV-positive and T0-3 or HPV-negative and T0-2; (ii) intermediate/high-risk: HPV-positive and T4 or HPV-negative and T3-4. Patient reported outcomes were carried out.

RESULTS

A total of 136 patients were randomized in the study, 68 to each arm. With a median follow up of 3.2 years, the 2-year PFS in the PCC arm was 89% in the overall, 96% in the low-risk and 67% in the intermediate/high-risk groups; in the C-TPF arm 2-year PFS was 88% in the overall, 88% in the low-risk and 89% in the intermediate/high-risk groups.

CONCLUSION

The observed 2-year PFS of PCC in the low-risk group and of C-TPF in the intermediate/high-risk group showed a 20% improvement compared with the historical control derived from RTOG-0129, therefore reaching the primary end point of the trial.

Absence of Inhibitors in Previously Untreated Patients with Severe Haemophilia A after Exposure to a Single Intermediate Purity Factor VIII Product

Use of high purity and recombinant factor VIII (FVIII) concentrates has been thought to be associated with an increased incidence of FVIII inhibitors in patients with severe haemophilia A. Comparison with comparable historical control groups has suggested that the true incidence of inhibitors in patients with severe haemophilia A was ~20-25%, similar to the incidence seen with new high purity and recombinant FVIII products.

We have conducted a study of inhibitor development in a cohort of 37 boys with severe haemophilia A (VIII: C <2 u/dl) exposed only to a single FVIII concentrate (BPL 8Y) with no previous blood or blood product exposure. This factor VIII concentrate is an intermediate purity product with a specific activity of ~2 IU/mg protein and contains well preserved von Willebrand factor multimers. It is manufactured by conventional fractionation technologies and terminally dry heat treated at 80° C for 72 h.

A Prospective Study of HIV-Infected Haemophilic Boys and the Prognostic Significance of Immune and Haematological Abnormalities

Fifty-seven haemophilic boys have been studied prospectively determining T lymphocyte subsets and haematological parameters over a period of 26 months. Clinical follow up of these patients has continued for a further 41 months. At the beginning of the study 21 boys were HIV antibody seropositive and seroconversion was documented in a further 9 during the study period, giving a 52.6% incidence of HIV seropositivity. It has been possible to define a group of patients with persistently falling T4 values and these have shown clinical evidence of HIV infection. Although persistent generalized lymphadenopathy has been observed in 30% of HIV antibody positive boys and some boys have had unexplained fevers, only one boy has progressed to have the acquired immune deficiency syndrome (AIDS) some 5 years and 3 months from HIV seroconversion. This boy had a persistently falling T4 value. The importance of these findings is discussed. To date the abnormalities found in these haemophilic boys irrespective of their age are similar to those already reported in adult haemophiliacs.

The effect of Nordic hamstring exercise training volume on biceps femoris long head architectural adaptation

The aim of this study was to determine the time course of architectural adaptations in the biceps femoris long head (BF_LH ) following high or low volume eccentric training. Twenty recreationally active males completed a two week standardized period of eccentric Nordic hamstring exercise (NHE) training, followed by four weeks of high (n = 10) or low volume (n = 10) training. Eccentric strength was assessed pre- and post intervention and following detraining. Architecture was assessed weekly during training and after two and four weeks of detraining. After six weeks of training, BF_LH fascicles increased significantly in the high (23% ± 7%, P < .001, d = 2.87) and low volume (24% ± 4%, P < .001, d = 3.46) groups, but reversed following two weeks of detraining (high volume: -17% ± 5%, P < .001, d = -2.04; low volume: -15% ± 3%, P < .001, d = -2.56) after completing the intervention. Both groups increased eccentric strength after six weeks of training (high volume: 28% ± 20%, P = .009, d = 1.55; low volume: 34% ± 14%, P < .001, d = 2.09) and saw no change in strength following a four week period of detraining (high volume: -7% ± 7%, P = .97, d = -0.31; low volume: -2% ± 5%, P = .99, d = -0.20). Both low and high volume NHE training stimulate increases in BF_LH fascicle length and eccentric knee flexor strength. Architectural adaptations reverted to baseline levels within two weeks after ceasing training, but eccentric strength was maintained for at least four weeks. These observations provide novel insight into the effects of training volume and detraining on BF_LH architecture and may provide guidance for the implementation of NHE programs.

Imaging of Anaplastic Thyroid Carcinoma

Anaplastic thyroid carcinoma is fatal if unresectable. However, improved survival has been reported after gross total resection and multimodality therapy. In this report, we describe the contrast-enhanced high-resolution CT characteristics of anaplastic thyroid carcinoma in 57 patients. Anaplastic thyroid carcinoma presented as a large neck mass with necrosis in 82% of cases. The tumors demonstrated common extrathyroidal extension (91%). Sixty-two percent of tumors demonstrated calcification. Visceral space invasion involved the esophagus (62%), trachea (57%), and larynx (29%). Carotid artery encasement was present in 42%, and 43% involved the internal jugular vein. Sixty-three percent had lateral compartment lymphadenopathy; 58% of these nodes were necrotic, and 11% were cystic. No metastatic nodes had calcification. Central compartment lymphadenopathy was seen in 56% of cases, and lateral retropharyngeal lymphadenopathy was detected in 12%. Knowledge of these imaging features aids in guiding the approach to the initial tissue diagnosis with either fine-needle aspiration or core biopsy, assessing the feasibility of surgical resection, and determining prognosis.

Hypoxic preconditioning of myoblasts implanted in a tissue engineering chamber significantly increases local angiogenesis via upregulation of myoblast vascular endothelial growth factor-A expression and downregulation of miRNA-1, miRNA-206 and angiopoietin-1

Vascularization is a major hurdle for growing three-dimensional tissue engineered constructs. This study investigated the mechanisms involved in hypoxic preconditioning of primary rat myoblasts in vitro and their influence on local angiogenesis postimplantation. Primary rat myoblast cultures were exposed to 90 min hypoxia at <1% oxygen followed by normoxia for 24 h. Real time (RT) polymerase chain reaction evaluation indicated that 90 min hypoxia resulted in significant downregulation of miR-1 and miR-206 (p < 0.05) and angiopoietin-1 (p < 0.05) with upregulation of vascular endothelial growth factor-A (VEGF-A; p < 0.05). The miR-1 and angiopoietin-1 responses remained significantly downregulated after a 24 h rest phase. In addition, direct inhibition of miR-206 in L6 myoblasts caused a significant increase in VEGF-A expression (p < 0.05), further establishing that changes in VEGF-A expression are influenced by miR-206. Of the myogenic genes examined, MyoD was significantly upregulated, only after 24 h rest (p < 0.05). Preconditioned or control myoblasts were implanted with Matrigel™ into isolated bilateral tissue engineering chambers incorporating a flow-through epigastric vascular pedicle in severe combined immunodeficiency mice and the chamber tissue harvested 14 days later. Chambers implanted with preconditioned myoblasts had a significantly increased percentage volume of blood vessels (p = 0.0325) compared with chambers implanted with control myoblasts. Hypoxic preconditioned myoblasts promote vascularization of constructs via VEGF upregulation and downregulation of angiopoietin-1, miR-1 and miR-206. The relatively simple strategy of hypoxic preconditioning of implanted cells - including non-stem cell types - has broad, future applications in tissue engineering of skeletal muscle and other tissues, as a technique to significantly increase implant site angiogenesis.

Environmental Nontuberculous Mycobacteria in the Hawaiian Islands

Lung disease caused by nontuberculous mycobacteria (NTM) is an emerging infectious disease of global significance. Epidemiologic studies have shown the Hawaiian Islands have the highest prevalence of NTM lung infections in the United States. However, potential environmental reservoirs and species diversity have not been characterized. In this cross-sectional study, we describe molecular and phylogenetic comparisons of NTM isolated from 172 household plumbing biofilms and soil samples from 62 non-patient households and 15 respiratory specimens. Although non-uniform geographic sampling and availability of patient information were limitations, Mycobacterium chimaera was found to be the dominant species in both environmental and respiratory specimens. In contrast to previous studies from the continental U.S., no Mycobacterium avium was identified. Mycobacterium intracellulare was found only in respiratory specimens and a soil sample. We conclude that Hawai’i’s household water sources contain a unique composition of Mycobacterium avium complex (MAC), increasing our appreciation of NTM organisms of pulmonary importance in tropical environments.

In the U.S., the Hawaiian Islands have the highest number of nontuberculous mycobacterial (NTM) lung disease cases per capita. The tropical climate, geographical isolation of the islands, and aquifer water sources may have influence such prevalence. Previous studies suggest that NTM thrive in water biofilms and soil. To broaden our understanding of potential environmental reservoirs and species composition of NTM in the Hawaiian Islands, we sampled environmental sites and examined patient isolates. Our recovery and identification of Mycobacterium chimaera and several other clinically relevant NTM species and the absence of Mycobacterium avium in both the indigenous environment and clinical specimens underscore the need for further studies to define the environmental factors that drive NTM lung disease and species composition in high prevalence locations such as the Hawaiian Islands.

Methylobacterium spp. as an indicator for the presence or absence of Mycobacterium spp

OBJECTIVE/BACKGROUND

A published survey of bacteria in showerhead biofilm samples revealed that Methylobacterium spp. and Mycobacterium spp. seldom coexisted in biofilms.

METHODS

To confirm that information, biofilm samples were collected from household plumbing of Mycobacterium avium patients and Methylobacterium spp. and M. avium numbers were measured by direct colony counts.

RESULTS

The results demonstrated that if Methylobacterium spp. were present, Mycobacterium spp. were absent, and the opposite.

CONCLUSION

The data demonstrate that microbial populations in biofilms can influence the presence or absence of opportunistic premise plumbing pathogens and, thereby, increase the range of strategies to reduce exposure to waterborne pathogens. Finally, by assessing for the visual presence of methylobacteria as pink pigmentation on showers and shower curtains, homeowners and managers of hospitals and other buildings can quickly determine whether a premise plumbing biofilm sample has mycobacteria with a high degree of assurance.

Central Nervous System and Head and Neck Histiocytoses: A Comprehensive Review on the Spectrum of Imaging Findings

The histiocytoses are a rare group of varied but related disorders characterized by abnormal tissue proliferation of macrophages and dendritic cells within tissues. The purpose of this article was to review the imaging findings in patients presenting with CNS and with head and neck manifestations of these disorders. Histiocytoses include but are not limited to Rosai-Dorfman disease, Erdheim Chester disease, Langerhans cell histiocytosis, histiocytic sarcoma, and juvenile xanthogranuloma. A review of the literature was performed to determine the sites of disease involvement. This article includes the demographics, histopathologic criteria for diagnosis, and imaging features of these histiocytoses, and describes the manifestations in locations known to harbor disease: intraaxial and extra-axial intracranial regions, the calvaria, skull base, hypothalamopituitary axis, orbits, paranasal sinuses, spine, and the head and neck region. Histiocytoses have variable imaging appearances in the CNS and in the head and neck region, and radiologists should be aware of the spectrum of findings to avoid mistaking them for other disease processes.

Learning Objective

To understand the general pathophysiology, clinical presentation, and typical imaging characteristics of the most common histiocytoses; comprehend the morphologic and immunohistochemical characteristics of these histiocytoses and the hallmark findings on pathology; and be able to differentiate between these disorders based on their most common presentations.

Ammonia gas transport and reactions in unsaturated sediments: implications for use as an amendment to immobilize inorganic contaminants

Use of gas-phase amendments for in situ remediation of inorganic contaminants in unsaturated sediments of the vadose zone may be advantageous, but there has been limited development and testing of gas remediation technologies. Treatment with ammonia gas has a potential for use in treating inorganic contaminants (such as uranium) because it induces a high pore-water pH, causing mineral dissolution and subsequent formation of stable precipitates that decrease the mobility of some contaminants. For field application of this treatment, further knowledge of ammonia transport in porous media and the geochemical reactions induced by ammonia treatment is needed. Laboratory studies were conducted to support calculations needed for field treatment design, to quantify advective and diffusive ammonia transport in unsaturated sediments, to evaluate inter-phase (gas/sediment/pore water) reactions, and to study reaction-induced pore-water chemistry changes as a function of ammonia delivery conditions, such as flow rate, gas concentration, and water content. Uranium-contaminated sediment was treated with ammonia gas to demonstrate U immobilization. Ammonia gas quickly partitions into sediment pore water and increases the pH up to 13.2. Injected ammonia gas advection front movement can be reasonably predicted by gas flow rate and equilibrium partitioning. The ammonia gas diffusion rate is a function of the water content in the sediment. Sodium, aluminum, and silica pore-water concentrations increase upon exposure to ammonia and then decline as aluminosilicates precipitate when the pH declines due to buffering. Up to 85% of the water-leachable U was immobilized by ammonia treatment.

Phase II trial of everolimus and erlotinib in patients with platinum-resistant recurrent and/or metastatic head and neck squamous cell carcinoma

BACKGROUND

Enhanced phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway is one of the key adaptive changes accounting for epidermal growth factor receptor (EGFR) inhibitor-resistant growth in head and neck squamous cell carcinoma (HNSCC). We designed a phase II clinical trial of EGFR tyrosine kinase inhibitor (TKI), erlotinib, in association with the mTOR inhibitor, everolimus, based on the hypothesis that the downstream effects of Akt through inhibition of mTOR may enhance the effectiveness of the EGFR-TKI in patients with recurrent/metastatic HNSCC.

PATIENTS AND METHODS

Patients with histologically or cytologically confirmed platinum-resistant HNSCC received everolimus 5 mg and erlotinib 150 mg daily orally until disease progression, intolerable toxicity, investigator or patient decision. Cytokines and angiogenic factors profile, limited mutation analysis and p16 immunohistochemistry status were included in the biomarker analysis.

RESULTS

Of the 35 assessable patients, 3 (8%) achieved partial response at 4 weeks, 1 confirmed at 12 weeks; overall response rate at 12 weeks was 2.8%. Twenty-seven (77%) patients achieved disease stabilization at 4 weeks, 11 (31%) confirmed at 12 weeks. Twelve-week progression-free survival (PFS) was 49%, median PFS 11.9 weeks and median overall survival (OS) 10.25 months. High neutrophil gelatinase lipocalin (P = 0.01) and vascular endothelial growth factor (VEGF) (P = 0.04) plasma levels were significantly associated with worse OS.

CONCLUSIONS

The combination of erlotinib and everolimus did not show significant benefit in unselected patients with platinum-resistant metastatic HNSCC despite a manageable toxicity profile. Markers of tumor invasion and hypoxia identify a group of patients with particularly poor prognosis.

CLINICAL TRIAL NUMBER

NCT00942734.

Procedure for fabricating biofunctional nanofibers

Electrospinning is an effective processing method for preparing nanofibers decorated with functional groups. Nanofibers decorated with functional groups may be utilized to study material-biomarker interactions i.e. act as biosensors with potential as single molecule detectors. We have developed an effective approach for preparing functional polymers where the functionality has the capacity of specifically binding with a model protein. In our model system, the functional group is 2,4-dinitrophenyl (DNP) and the protein is anti-DNP IgE (Immunoglobulin E). The functional polymer, α,ω-bi[2,4-dinitrophenyl caproic][poly(ethylene oxide)-b-poly(2-methoxystyrene)-b-poly(ethylene oxide)] (CDNP-PEO-P2MS-PEO-CDNP), is prepared by anionic living polymerization. The difunctional initiator utilized in the polymerization was prepared by electron transfer reaction of α-methylstyrene and potassium (mirror) metal. The 2-methoxystyrene monomer was added first to the initiator, followed by the addition of the second monomer, ethylene oxide, and finally the living polymer was terminated by methanol. The α,ω-dihydroxyl polymer [HO-PEO-P2MS-PEO-OH] was reacted with N-2,4-DNP-∈-amino caproic acid, by DCC coupling, resulting in the formation of α,ω-bi[2,4-dinitrophenylcaproic][poly(ethyleneoxide)-b-poly(2-methoxystyrene)-b-poly(ethylene oxide)] (CDNP-PEO-P2MS-PEO-CDNP). The polymers were characterized by FT-IR, (1)H NMR and Gel Permeation Chromatography (GPC). The molecular weight distributions of the polymers were narrow (1.1-1.2) and polymers with molecular weights greater than 50,000 was used in this study. The polymers were yellow powders and soluble in tetrahydrofuran. A water soluble CDNP-PEO-P2MS-PEO-CDNP/ DMEG (dimethoxyethylene glycol) complex binds and achieves steady state binding with solution IgE within a few seconds. Higher molecular weight (water insoluble i.e. around 50,000) CDNP-PEO-P2MS-PEO-CDNP polymers, containing 1% single wall carbon nanotubes (SWCNT) were processed into electroactive nanofibers (100 nm to 500 nm in diameter) on silicon substrate. Fluorescence spectroscopy shows that anti-DNP IgE interacts with the nanofibers by binding with the DNP functional groups decorating the fibers. These observations suggest that appropriately functionalized nanofibers hold promise for developing biomarker detection device.

Erdheim-Chester disease of the central nervous system: new manifestations of a rare disease

BACKGROUND AND PURPOSE

ECD is a rare non-Langerhans-cell histiocytosis, which can involve the CNS; therefore, CNS imaging findings have been described in only a small number of patients. To gain additional insight into the CNS manifestations of ECD, we reviewed the findings on imaging of the brain, head and neck, and spine in patients with ECD who presented to our institution. Here, we illustrate manifestations that have not, to our knowledge, been previously described.

MATERIALS AND METHODS

CT, MR imaging, and PET/CT studies of the brain, maxillofacial region, and spine were reviewed in 11 patients with ECD.

RESULTS

Four new manifestations of ECD were present, including the following: a stellate appearance of intracranial extra-axial lesions, ependymal enhancement along the lateral ventricle with deep linear extension to the lentiform nucleus, irregular enhancement in the pons, and diffuse involvement of the vertebral column on PET/CT.

CONCLUSIONS

ECD has a variety of imaging appearances in the CNS, including new manifestations described herein. Neuroradiologists should be aware of these manifestations to avoid mistaking them for other disease processes.

Management of devastating ocular trauma--experience of maxillofacial surgeons deployed to a forward field hospital

Combat-related eye injuries continue to increase in frequency and are generally secondary to Improvised Explosive Devices. Many ocular injuries are potentially preventable by the wearing of ballistic eye protection. The management of penetrating eye trauma is normally outside the routine practice of maxillofacial surgeons in the UK. The aim of this paper is to describe the surgical techniques used in the modern management of devastating ocular trauma including selected case examples managed by British military maxillofacial surgeons deployed to Afghanistan.

Thyroid function and the natural history of depression: findings from the Caerphilly Prospective Study (CaPS) and a meta-analysis

OBJECTIVE

Low thyroid function has been associated with depression in clinical populations. We have examined whether thyroid function in the normal range is associated with minor psychiatric morbidity.

DESIGN

Prospective cohort study of 2269 middle aged men (45-59 years) with thyroid function (total T(4) only, TSH unavailable) measured between 1979 and 1983 and with repeat measures of minor psychiatric morbidity (GHQ-30) over a mean of 12.3 years follow-up. We also undertook a systematic review and meta-analysis of population-based studies examining thyroid function and mood.

RESULTS

There was a positive association between total T(4) and chronic psychiatric morbidity (odds ratio 1.21, 95% CI 1.02-1.43, P= 0.03), but this was consistent with chance after adjusting for social class, alcohol and smoking behaviours. The association with incident and recovery from psychiatric morbidity was weaker and consistent with chance. We identified seven eligible studies, from our systematic review and included six studies, including our own, in a meta-analysis. The pooled estimate showed a positive association (odds ratio 1.12, 95% CI 1.02-1.22, P-value = 0.01) between depression and T(4) and an inverse association with TSH (odds ratio 0.92, 95% CI 0.88-0.97, P= 0.0007) with no evidence of heterogeneity or publication bias.

CONCLUSION

The results from CaPS and our meta-analysis are consistent and suggest that, if anything, higher levels of thyroxine in the normal range are associated with increased risk of depression. The effects of thyroid hormone on mood may differ in normal populations and patients with clinical thyroid dysfunction.

A comparative study of anticoagulant control in patients on long-term warfarin using home and hospital monitoring of the international normalised ratio

BACKGROUND

Capillary whole-blood point-of-care prothrombin-INR (PT-INR) testing at home is an alternative to hospital-based monitoring for patients on lifelong warfarin.

AIM

To retrospectively assess the safety and efficacy of home point-of-care testing for children on long-term warfarin.

METHOD

All patients who had been on point-of-care home monitoring for at least 6 months were included in the study. Their warfarin control was assessed while on home monitoring and compared to that achieved in a similar period before changing from hospital monitoring.

RESULTS

Thirty-seven patients were studied for a mean of 1.0 year on clinic monitoring and 1.07 years on home monitoring. The clinic monitoring tests were within a therapeutic range for a median 70.0 (inter-quartile range 34.5) and the home monitoring were within range for median 75.0 (inter-quartile range 44.5). There were no major haemorrhagic or thrombotic complications in either group during the study period. Only 2.3% of all tests had an INR greater than 6.0 with no statistical differences seen between the clinic and home monitoring groups.

CONCLUSION

Home point-of-care testing in children on lifelong warfarin is safe, effective and offers a number of advantages to the child and family. Ongoing training and support for the families is essential for this service.

Parotid gland oncocytosis: CT findings with histopathologic correlation

Oncocytic neoplasms result from metabolically altered cells that accumulate abundant mitochondria within their cytoplasm by oncocytic metaplasia. In this report, the CT findings are described and correlated with the histopathologic features of a case of oncocytoma involving the parotid gland that arose in a background of nodular oncocytic hyperplasia. When imaging demonstrates multiple small nodules in the parotid gland with a large, solid, or cystic mass, the diagnosis of oncocytic neoplasia should be considered.

Early factor VIII exposure and subsequent inhibitor development in children with severe haemophilia A

Recent reports have suggested that the incidence of inhibitors in haemophilia is the highest in those first exposed to factor VIII under 6 months of age. In this study, we investigated inhibitor development in children first exposed to FVIII as neonates and also examined the effect of other genetic and environmental variables. Three hundred and forty-eight children with severe haemophilia A were investigated. Inhibitors developed in 68 of 348 (20%), with 34 of 348 (10%) high titre inhibitors. The incidence in relation to initial FVIII exposure was: <1 month nine of 35 (26%), 1-6 months 13 of 51 (25%), 6-12 months 27 of 130 (21%), 12-18 months 13 of 66 (20%) and >18 months six of 66 (9%). While we observed a significant difference in inhibitor development and age at first exposure across all age groups (P = 0.018), no significant difference was observed in children treated at different time points during the first year of life (P = 0.44). Similar results were obtained for high titre inhibitors. There was also no difference in the incidence of inhibitors in relation to initial FVIII exposure in a subgroup of 144 children with the intron 22 mutation. Inhibitors developed more frequently in those initially treated with recombinant when compared with plasma-derived FVIII (P = 0.006) and in those with a major molecular defect (P = 0.009). In this study, exposure to FVIII during the neonatal period was not associated with a higher incidence of inhibitors than those treated later during the first year of life. Initial treatment with recombinant FVIII and the presence of a major molecular defect were the most important variables affecting inhibitor development.

"One-stop" clinics in the investigation and diagnosis of head and neck lumps

This article considers the issues raised by the NICE guidelines "Improving outcomes in head and neck cancers" (2004) with particular emphasis on the guidelines regarding the creation of "one-stop" neck lump assessment clinics. Tissue sampling is an essential function of the clinics and the relative merits of fine needle aspiration cytology (FNAC) and ultrasound-guided core biopsy (US-CB) in the context of a one-stop model are discussed. All cancer service providers in the UK have a duty to implement the NICE guidelines, with the intention of improving cancer services to our patients. The measures against which head and neck cancer teams are to be accredited through the process of peer review will specify such a clinic to be in place. Teams should implement the guidance in such a way that there is a genuine benefit to patients. In many centres this may require clinicians to learn new skills and adopt different ways of working.

Ultrasound-guided core biopsy for the diagnosis of lumps in the neck: results in 82 patients

Ultrasound-guided core biopsy of nodes (n = 78) and other lumps (n = 4) in the neck allowed a firm histological diagnosis in 76 of 82 patients (93%). Of the remaining six patients, histological examination was equivocal in four and valueless in two. Of 18 patients with a diagnosis of lymphoma only 3 required excision of the node to provide additional information for the planning of treatment.

A safety evaluation of drotrecogin alfa (activated) in hematopoietic stem cell transplant patients with severe sepsis: lessons in clinical research

We conducted an open-label, multicenter, single-arm clinical trial to investigate the safety and efficacy of drotrecogin alfa (activated) (Drot AA) in hematopoietic stem cell transplant (HSCT) patients with severe sepsis. Drot AA was administered as a continuous i.v. infusion of 24 microg/kg/h for 96 h. The target enrollment was 250 patients in 15-20 transplant centers over a 2-year period (March 2003-March 2005). However, after only 10 months, in December 2003, the trial was stopped due to a low enrollment of seven patients at three of the 15 sites that were open for accrual. Six of the seven patients completed the drug infusion. Two patients experienced serious bleeding events. The first patient developed a nonfatal diffuse alveolar hemorrhage 2 days after study-drug completion. The second patient had severe coagulopathy and developed a fatal intracranial hemorrhage on the third day of drug infusion. Three of the seven patients were alive 100 days after the HSCT. The slow enrollment rate was attributed to changes in transplant preparatory regimens, enhancements in antimicrobial prophylactic protocols and the use of antimicrobial-coated catheters. The small number of patients in this report precludes a definitive assessment of the safety and efficacy of Drot AA in HSCT patients.

The rare coagulation disorders - review with guidelines for management from the United Kingdom Haemophilia Centre Doctors' Organisation

The rare coagulation disorders are heritable abnormalities of haemostasis that may present significant difficulties in diagnosis and management. This review summarizes the current literature for disorders of fibrinogen, and deficiencies of prothrombin, factor V, FV + VIII, FVII, FX, the combined vitamin K-dependent factors, FXI and FXIII. Based on both collective clinical experience and the literature, guidelines for management of bleeding complications are suggested with specific advice for surgery, spontaneous bleeding, management of pregnancy and the neonate. We have chosen to include a section on Ehlers-Danlos Syndrome because haematologists may be consulted about bleeding manifestations in such patients.

Experience with routine intraabdominal cultures during laparoscopic gastric bypass with implications for antibiotic prophylaxis

BACKGROUND

Techniques for laparoscopic Roux-en-Y gastric bypass that do not use bowel cross-clamping raise a question of increased risk for infectious complications. However, to the authors' knowledge, no studies have recorded routine intraoperative peritoneal cultures. This article reports the authors' experience with routine peritoneal cultures during laparoscopic Roux-en-Y gastric bypass and the role of antibiotic prophylaxis.

METHODS

From January 2000 to March 2000, 66 consecutive patients undergoing a laparoscopically divided proximal Roux-en-Y gastric bypass had peritoneal fluid aspirated for routine culture. No mechanical or oral antibiotic bowel preparation was used. All the patients received preoperative intravenous antibiotic prophylaxis with Levoquin 500 mg and Flagyl 500 mg. Peritoneal fluid was aspirated from the left gutter near the site of the enteroenterostomy before irrigation with 1,000 ml of normal saline containing 50,000 U of bacitracin and 1 of kanamycin.

RESULTS

The follow-up period averaged 9 months for 100% of patients. For 15 patients (22.7%), the culture results were positive. The 22 organisms cultured involved 15 streptococcus species, 4 anaerobes, 2 staphylococcus species, and 1 enterobacter. None of the patients experienced a clinical infection or required an extension of antibiotics beyond the first 24 h.

CONCLUSIONS

This study demonstrated frequent peritoneal contamination during laparoscopic gastric bypass. Prophylactic intravenous antibiotics and antibiotic irrigation may have reduced the risk of clinically significant infections in this small uncontrolled series.

Gadolinium an alternative contrast agent for sialography in patients with iodine sensitivity

The use of iodinated contrast material in radiography is contraindicated in patients with known iodine sensitivity and such patients may present a management dilemma. The successful use of gadolinium in contrast sialography is described.

Massive acute haemolysis in neonates with glucose-6-phosphate dehydrogenase deficiency

Three neonates with glucose-6-phosphate dehydrogenase (G6PD) deficiency are described. All three patients suffered an episode of massive acute haemolysis, in the absence of blood group incompatibilities, infection, or ingestion of oxidising agents known to trigger haemolysis. One patient died, but the other two survived after an exchange transfusion. This highlights that G6PD deficiency in the neonatal period may present with severe anaemia in association with hyperbilirubinaemia.

Prenatal origin of hyperdiploid acute lymphoblastic leukemia in identical twins

Studies in identical twins and with neonatal blood spots (Guthrie cards) have backtracked the origin of childhood acute leukemia and their associated chromosomal translocations to before birth. High hyperdiploidy is the most common genetic abnormality in childhood acute lymphoblastic leukemia (ALL). Evidence for an in utero initiation of this important genetic event in ALL is available from blood spots but remains limited. Twin children with hyperdiploid ALL have not hitherto been reported. We describe a pair of 2-year-old monozygotic twins with concordant B-cell precursor ALL and hyperdiploid karyotypes. One twin's leukemic cells had two rearranged TCRD alleles and one of these was a clonotypic Vdelta2-Ddelta3 sequence shared with leukemic cells of the other twin. The twins' leukemic cells had several different IGH V(H)-J(H) rearrangements but shared two common D(H)-J(H) 'stem' sequences. We conclude that ALL in these twins is likely to have originated prenatally in one fetus before spreading to the other via intraplacental anastomoses. It is likely that one or more additional postnatal genetic events was required for overt leukemogenesis.

Laparoscopic approach to the management of intraabdominal unicentric Castleman?s disease

Castleman's disease, or angiofollicular lymphoid hyperplasia, is a rare lymphoproliferative disorder of unknown etiology. We present the case of an 18-year-old woman who was admitted with symptoms of fatigue, weakness, early satiety, and weight gain. A subhepatic mass anterior to the pancreas was discovered on ultrasound. After being treated via the laparoscopic approach with complete surgical resection she recovered well. This case thus represents a new application for laparoscopy and expands the indications for its use.

Laparoscopic ventral hernia repair during the learning curve

Large series of laparoscopic ventral hernia repair have shown excellent results. However, published comparative studies have had conflicting outcomes. We retrospectively reviewed the first 29 laparoscopic ventral hernia repairs performed at a VA Medical Center from January 2000 to June 2001. The outcome was compared to that of open repairs performed during the same time period. Outcomes between the groups were similar in all respects, except for the length of stay. The conversion rate for the laparoscopic approach was 13.8%. There was one death in the laparoscopic group due to an unrecognized enterotomy. There were three recurrences in the open group and one in the laparoscopic group with a mean follow up of 13 months. In our series, laparoscopic hernia repair resulted in a shorter hospital stay but no other significant benefits, along with a risk of missed enterotomy. The risk-benefit ratio for this procedure may be high during the learning curve.

Knockout mice heterozygous for Sod2 show alterations in cardiac mitochondrial function and apoptosis

Heart mitochondria from heterozygous (Sod2(-/+)) knockout mice have a 50% reduction in manganese superoxide dismutase (MnSOD) activity. The decrease in MnSOD activity was associated with increased mitochondrial oxidative damage as demonstrated by a decrease in the activities of iron sulfhydryl proteins sensitive to oxygen stress (aconitase and reduced nicotinamide adenine dinucleotide-oxidoreductase). Mitochondrial function was altered in the Sod2(-/+) mice, as shown by decreased respiration by complex I and an increase in the sensitivity of the permeability transition to induction by calcium and t-butylhydroperoxide. The increased induction of the permeability transition in heart mitochondria from Sod2(-/+.)mice was associated with increased release of cytochrome c and an increase in DNA fragmentation. Cardiomyocytes isolated from neonatal Sod2(-/+) and Sod2(-/-) mice were more sensitive to cell death than cardiomyocytes from Sod2(+/+) mice after t-butylhydroperoxide treatment, and this increased sensitivity was prevented by inhibiting the permeability transition with cyclosporin A. These experiments demonstrate that MnSOD may play an important role in the induction of the mitochondrial pathway of apoptosis in the heart, and this appears to occur primarily through the permeability transition.

Aberrant dimerization of von Willebrand factor as the result of mutations in the carboxy-terminal region: identification of 3 mutations in members of 3 different families with type 2A (phenotype IID) von Willebrand disease

The 3' end of the VWF gene was screened in the affected members of 3 different families with type 2A (phenotype IID) von Willebrand disease (vWD). Exons 49 to 52 of the VWF gene were amplified and screened for mutations by chemical cleavage mismatch detection. Mismatched bands were detected in exon 52 of 2 patients and in exon 51 of a third patient. Using direct DNA sequencing, a heterozygous G8562A transition leading to a Cys2008Tyr substitution was found in all the patients in family 1, and a T8561A transversion leading to a Cys2008Ser substitution was found in both patients from family 2. In a patient from a third family, an 8-base deletion from nucleotide 8437 to 8444 was identified in exon 51. The 2 mutations in exon 52 were reproduced by in vitro site-directed mutagenesis of full-length von Willebrand factor (vWF) cDNA and transiently expressed in COS-7 cells. The corresponding recombinant VWFs for these 2 mutations exhibited the typical aberrant vWF:Ag multimer pattern seen in the plasma of the patients. These 3 mutations demonstrate the importance of other carboxy-terminal cysteines in addition to the reported Cys2010 residue, in the normal dimerization of vWF, and their essential role in the assembly of normal multimeric vWF. (Blood. 2001;98:674-680)