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1.
Clin Oncol (R Coll Radiol) ; 34(6): 398-406, 2022 06.
Article in English | MEDLINE | ID: mdl-35065849

ABSTRACT

AIM: To evaluate the value of a multidisciplinary team (MDT), including a neuroradiologist and a neurosurgeon, review of contouring in stereotactic radiosurgery (SRS). MATERIALS AND METHODS: A sequential audit of all patients receiving intracranial SRS at local institution was conducted. Lesions were contoured first by a clinical oncologist, then reviewed/edited by the MDT. The initial contour was compared with the final contour using Jaccard conformity (JCI) and geographical miss indices (GMI). The dosimetric impact of a contouring change was assessed using plan metrics to both original and final contours. RESULTS: In total, 113 patients and 142 lesions treated over 22 months were identified. The mean JCI was 0.92 (0.32-1.00) and 38% needed significant editing (JCI <0.95). The mean GMI was 0.03 (0.0-0.65) and 17% showed significant miss (GMI >0.05). Resection cavities showed more changes, with lower JCI and higher GMI (P < 0.05). There was no significant improvement on JCI or GMI shown over time. The dosimetric analysis indicated a strong association of conformity metrics with planning target volume dose metrics; a 0.1 change in gross tumour volume conformity metric association with a 6-17% change in dose to 95% of the resulting planning target volume. Greater association was seen in the resection cavity, suggesting the geographical nature of a typical contouring error gives rise to greater potential change in dose. Clinical outcomes compared well with published series. The median survival was 20 months; the local relapse-free rate in the treated areas was 0.89 (0.8-0.94) at 40 months; the radionecrosis-free rate at 40 months was 0.9 (0.83-0.95) with a median of 17 months to developing radionecrosis. CONCLUSIONS: This work highlights that MDT contour review adds significant value to SRS and the approach translates into reduced local recurrence rates at the local institution compared with previously published data. No improvement in clinical oncologist contouring over time was shown, indicating that a collaborative approach is needed regardless of the experience of the clinical oncologist. MDT input is recommended in particular for contouring of resection cavities.


Subject(s)
Brain Neoplasms , Oncologists , Radiation Injuries , Radiosurgery , Brain Neoplasms/surgery , Humans , Neurosurgeons , Radiation Injuries/etiology , Radiosurgery/methods , Retrospective Studies , Treatment Outcome
3.
J Pharmacol Toxicol Methods ; 102: 106660, 2020.
Article in English | MEDLINE | ID: mdl-31838234

ABSTRACT

INTRODUCTION: Platelets are under investigation for their role in host defence and inflammatory lung diseases and have been demonstrated to be recruited to the lung. However, the mechanisms and consequences of platelet recruitment into lungs are poorly understood. We have utilised a murine model to investigate the mechanisms of platelet involvement in lung inflammation induced by intranasal administration of LPS. OBJECTIVES: Our aim was to characterise lung platelet recruitment following LPS inhalation in mice using immunohistochemistry, and non-invasive and invasive radiolabelled platelet tracking techniques. RESULTS: Intranasal administration of LPS caused an increase in lung platelet staining in lung tissue and elicited the recruitment of radiolabelled platelets into the lung. Prior to these responses in the lung, we observed an earlier decrease in blood platelet counts, temporally associated with platelet recruitment to the liver and spleen. Non-invasive measurements of thoracic radioactivity reflected changes in blood counts rather than extravascular lung platelet recruitment. However, both in situ counting of radiolabelled platelets and immunostaining for platelet surface markers showed LPS-induced increases in extravascular platelets into lung airspaces suggesting that some of the platelets recruited to the lung enter air spaces. CONCLUSIONS: Intranasal administration of LPS activates the innate immune response which includes a fall in peripheral blood platelet counts with subsequent platelet recruitment to the lung, spleen and liver, measured by immunohistochemistry and radiolabelling techniques.


Subject(s)
Blood Platelets/metabolism , Inflammation/physiopathology , Lung Diseases/physiopathology , Lung/metabolism , Administration, Inhalation , Animals , Cell Movement/physiology , Female , Immunity, Innate/physiology , Immunohistochemistry , Inflammation/immunology , Lipopolysaccharides/administration & dosage , Liver/metabolism , Lung Diseases/immunology , Mice , Mice, Inbred BALB C , Platelet Count , Radioisotopes , Spleen/metabolism
4.
J Control Release ; 301: 13-27, 2019 05 10.
Article in English | MEDLINE | ID: mdl-30853527

ABSTRACT

The regeneration of complex tissues and organs remains a major clinical challenge. With a view towards bioprinting such tissues, we developed a new class of pore-forming bioink to spatially and temporally control the presentation of therapeutic genes within bioprinted tissues. By blending sacrificial and stable hydrogels, we were able to produce bioinks whose porosity increased with time following printing. When combined with amphipathic peptide-based plasmid DNA delivery, these bioinks supported enhanced non-viral gene transfer to stem cells in vitro. By modulating the porosity of these bioinks, it was possible to direct either rapid and transient (pore-forming bioinks), or slower and more sustained (solid bioinks) transfection of host or transplanted cells in vivo. To demonstrate the utility of these bioinks for the bioprinting of spatially complex tissues, they were next used to zonally position stem cells and plasmids encoding for either osteogenic (BMP2) or chondrogenic (combination of TGF-ß3, BMP2 and SOX9) genes within networks of 3D printed thermoplastic fibers to produce mechanically reinforced, gene activated constructs. In vivo, these bioprinted tissues supported the development of a vascularised, bony tissue overlaid by a layer of stable cartilage. When combined with multiple-tool biofabrication strategies, these gene activated bioinks can enable the bioprinting of a wide range of spatially complex tissues.


Subject(s)
Bioprinting , Gene Transfer Techniques , Ink , Tissue Engineering , Alginates , Animals , Bone Morphogenetic Protein 2/genetics , DNA/administration & dosage , Hydrogels , Mesenchymal Stem Cells , Methylcellulose , Plasmids , Porosity , Printing, Three-Dimensional , SOX9 Transcription Factor/genetics , Swine , Transforming Growth Factor beta3/genetics
5.
Acta Biomater ; 55: 226-238, 2017 06.
Article in English | MEDLINE | ID: mdl-28363788

ABSTRACT

Controlling the phenotype of mesenchymal stem cells (MSCs) through the delivery of regulatory genes is a promising strategy in tissue engineering (TE). Essential to effective gene delivery is the choice of gene carrier. Non-viral delivery vectors have been extensively used in TE, however their intrinsic effects on MSC differentiation remain poorly understood. The objective of this study was to investigate the influence of three different classes of non-viral gene delivery vectors: (1) cationic polymers (polyethylenimine, PEI), (2) inorganic nanoparticles (nanohydroxyapatite, nHA) and (3) amphipathic peptides (RALA peptide) on modulating stem cell fate after reporter and therapeutic gene delivery. Despite facilitating similar reporter gene transfection efficiencies, these nanoparticle-based vectors had dramatically different effects on MSC viability, cytoskeletal morphology and differentiation. After reporter gene delivery (pGFP or pLUC), the nHA and RALA vectors supported an elongated MSC morphology, actin stress fibre formation and the development of mature focal adhesions, while cells appeared rounded and less tense following PEI transfection. These changes in MSC morphology correlated with enhanced osteogenesis following nHA and RALA transfection and adipogenesis following PEI transfection. When therapeutic genes encoding for transforming growth factor beta 3 (TGF-ß3) and/or bone morphogenic protein 2 (BMP2) were delivered to MSCs, nHA promoted osteogenesis in 2D culture and the development of an endochondral phenotype in 3D culture, while RALA was less osteogenic and appeared to promote a more stable hyaline cartilage-like phenotype. In contrast, PEI failed to induce robust osteogenesis or chondrogenesis of MSCs, despite effective therapeutic protein production. Taken together, these results demonstrate that the differentiation of MSCs through the application of non-viral gene delivery strategies depends not only on the gene delivered, but also on the gene carrier itself. STATEMENT OF SIGNIFICANCE: Nanoparticle-based non-viral gene delivery vectors have been extensively used in regenerative medicine, however their intrinsic effects on mesenchymal stem cell (MSC) differentiation remain poorly understood. This paper demonstrates that different classes of commonly used non-viral vectors are not inert and they have a strong effect on cell morphology, stress fiber formation and gene transcription in MSCs, which in turn modulates their capacity to differentiate towards osteogenic, adipogenic and chondrogenic lineages. These results also point to the need for careful and tissue-specific selection of nanoparticle-based delivery vectors to prevent undesired phenotypic changes and off-target effects when delivering therapeutic genes to damaged or diseased tissues.


Subject(s)
Gene Transfer Techniques , Materials Testing , Mesenchymal Stem Cells/metabolism , Nanoparticles/metabolism , Animals , Durapatite/chemistry , Durapatite/pharmacology , Mesenchymal Stem Cells/cytology , Peptides/chemistry , Peptides/pharmacology , Polyethyleneimine/chemistry , Polyethyleneimine/pharmacology , Swine
7.
Prostate Cancer Prostatic Dis ; 19(1): 100-6, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26754260

ABSTRACT

BACKGROUND: In men with high Gleason PC and rapid PSA progression after surgery, failure rates remain unacceptably high despite salvage radiation. We explored a novel multimodality approach of docetaxel with anti-angiogenic therapy before salvage radiotherapy (RT). METHODS: This was a phase 2 single-arm prospective open-label trial with historic controls. Eligible men had a rising PSA of 0.1-3.0 ng ml(-1) within 4 years of radical prostatectomy, no metastases except resected nodal disease, no prior androgen-deprivation therapy (ADT) and Gleason 7-10. Men received four cycles of docetaxel 70 mg m(-2) every 3 weeks with low dose prednisone and sunitinib 37.5 mg daily for 14/21 days each cycle, with no ADT. Salvage prostate bed RT (66 Gy) started at day 100. The primary end point was progression-free survival (PFS) rate at 24 months. Safety data, quality of life (QOL) and dose-limiting toxicities (DLTs) were measured over time. RESULTS: Thirty-four men accrued in this multi-institutional clinical trial: 24% of men were node positive, 47% were Gleason 8-10, median PSA at entry was 0.54. The trial was terminated prematurely owing to excess DLTs (nine) including grade 3 hand-foot syndrome (n=4), neutropenic fever (n=2), AST increase (n=1), fatigue (n=1) and vomiting with diarrhea (n=1). PFS rate at 24 months was 51% (95% CI: 33, 67%) with a median PFS of 26.2 months (95% CI: 12.5, -). Six men (17.6%) had an undetectable PSA at 2 years. CONCLUSIONS: Sunitinib and docetaxel/prednisone followed by salvage RT resulted in excess pre-specified DLTs. Although nearly half of the men experienced durable disease control, efficacy was not greater than expected with radiation alone. The use of the intermediate end point of PFS in this salvage setting permitted an early decision on further development of this combination.


Subject(s)
Indoles/administration & dosage , Neoplasm Recurrence, Local/drug therapy , Prednisone/administration & dosage , Prostatic Neoplasms/drug therapy , Pyrroles/administration & dosage , Taxoids/administration & dosage , Adult , Aged , Disease-Free Survival , Docetaxel , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Grading , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/radiotherapy , Prostate-Specific Antigen/metabolism , Prostatectomy , Prostatic Neoplasms/pathology , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Quality of Life , Salvage Therapy , Sunitinib
8.
J Perinatol ; 35(3): 198-203, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25275696

ABSTRACT

OBJECTIVE: The aim of this study is to investigate the association between birth defects (BDs), prematurity and small-for-gestational age (SGA) in a population-based sample. STUDY DESIGN: Participants were singleton live births enrolled in the National Birth Defects Prevention Study, including 18 737 case infants with one or more BD and 7999 controls. Logistic regression models to evaluate associations between BDs, prematurity and fetal growth were computed while adjusting for covariates. RESULT: Cases were significantly more likely to be born prematurely than controls, particularly at 24 to 28 weeks of gestation. The highest odds ratios for preterm birth were found for intestinal atresia, anencephaly, gastroschisis and esophageal atresia. Infants with BDs were also significantly more likely to be SGA than controls (17.2 and 7.8%). CONCLUSION: Infants with BDs are more likely than controls to be born prematurely and SGA. Findings from this study present additional evidence demonstrating a complex interaction between the development of BDs, prematurity and intrauterine growth.


Subject(s)
Congenital Abnormalities/epidemiology , Infant, Small for Gestational Age , Premature Birth/epidemiology , Adult , Birth Weight , Case-Control Studies , Female , Gestational Age , Humans , Infant, Extremely Premature , Infant, Newborn , Logistic Models , Male , Odds Ratio , Pregnancy , Young Adult
9.
Eur J Pain ; 17(4): 514-26, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23169679

ABSTRACT

BACKGROUND: Osteoarthritis (OA) is a highly prevalent, age-related pain condition that poses a significant clinical problem. Here, in the monosodium iodoacetate (MIA) model of OA, we have characterized pain behaviours and associated changes at the first pain synapse in the dorsal horn of the spinal cord. METHODS: Mice received intra-articular injections of 0.5, 0.75 and 1 mg MIA and mechanical paw withdrawal threshold was monitored for up to 4 weeks. An intrathecal injection of peptide antagonist calcitonin gene-related peptide (CGRP8-37 ) was given 3 weeks post MIA and paw withdrawal thresholds were measured after 1 and 3 h. Immunohistochemical analysis of the lumbar dorsal horn was carried out and activity-evoked CGRP release was measured from isolated lumbar dorsal horn slices - with dorsal roots attached. RESULTS: By 2 weeks after intra-articular MIA injection, mechanical hypersensitivity was established in the ipsilateral hindpaw. There was no evidence of sensory neuron damage in lumbar dorsal root ganglia 7 days after 1 mg MIA. However, both dorsal horn neuron activation and microglial response (Fos and Iba-1 immunostaining) but not reactive astrocytes (glial fibrillary acidic protein) were observed. Evoked CGRP release was greater from dorsal horn slices of MIA-treated mice compared with control. Furthermore, intrathecal administration of peptide antagonist CGRP8-37 acutely attenuated established MIA-induced mechanical hypersensitivity. CONCLUSIONS: Intra-articular MIA is associated with referred mechanical hypersensitivity and increased release of CGRP from primary afferent fibres in the dorsal horn where second-order neuron activation is associated with a microglial response. Antagonism of CGRP receptor activation provides a therapeutic avenue for the treatment of pain in OA.


Subject(s)
Arthritis, Experimental/physiopathology , Hyperalgesia/physiopathology , Osteoarthritis/physiopathology , Posterior Horn Cells/physiology , Spinal Cord/physiopathology , Animals , Arthritis, Experimental/chemically induced , Arthritis, Experimental/metabolism , Behavior, Animal/drug effects , Behavior, Animal/physiology , Calcitonin Gene-Related Peptide/pharmacology , Hyperalgesia/chemically induced , Hyperalgesia/metabolism , Iodoacetic Acid , Male , Mice , Mice, Inbred C57BL , Microglia/metabolism , Motor Activity/physiology , Osteoarthritis/chemically induced , Osteoarthritis/metabolism , Peptide Fragments/pharmacology , Physical Stimulation , Posterior Horn Cells/drug effects , Posterior Horn Cells/metabolism , Spinal Cord/drug effects , Spinal Cord/metabolism
10.
J Laryngol Otol ; 126(10): 1033-40, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22992270

ABSTRACT

INTRODUCTION: Endoscopic, transnasal management of pituitary gland neoplasms is a widely accepted alternative to the traditional microscopic approach. This study aimed to determine outcomes and complication rates for the largest UK series of endoscopic, trans-sphenoidal hypophysectomies reported to date. METHODS: We performed a retrospective analysis of 136 primary resections and 35 revision cases performed at a tertiary referral centre. RESULTS AND ANALYSIS: Total tumour resection was confirmed in over 85 per cent of primary and revision cases, with biochemical remission in 60 per cent. The incidence of complications such as epistaxis, sphenoid sinus problems, endocrine insufficiency, visual disturbance, post-operative haemorrhage, cranial nerve injury and mortality was significantly lower, compared with similar series using the microscopic approach. CONCLUSION: Despite its steep 'learning curve', our series demonstrates that the endoscopic approach not only allows superior anatomical visualisation and therefore facilitates full oncological resection of tumours, but also reduces the incidence of peri-operative complications.


Subject(s)
Adenoma/surgery , Endoscopy/methods , Hypophysectomy/methods , Pituitary Neoplasms/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Endoscopy/adverse effects , Female , Humans , Hypophysectomy/adverse effects , Male , Middle Aged , Postoperative Complications , Reoperation , Young Adult
12.
J Laryngol Otol ; 125(3): 311-3, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21106141

ABSTRACT

OBJECTIVE: Cerebrospinal fluid leakage is the most common complication of endoscopic trans-sphenoidal pituitary surgery. However, there is no uniformly accepted way of managing this complication when it occurs intra-operatively. This paper describes a quick, simple technique, involving layered fibrin glue and gelatin sponge, which does not compromise post-operative patient follow up. METHOD: Retrospective review of all endoscopic pituitary surgery cases conducted at a single institution since the introduction of this technique in 2002. RESULTS: A total of 120 endoscopic pituitary operations were performed (96 primary procedures and 24 revisions). All intra-operative cerebrospinal fluid leaks were managed using the described method, with a failure rate of 3.6 per cent. The overall post-operative leakage rate was 1.7 per cent. CONCLUSION: This simple, conservative technique avoids the need for further dissection and the use of non-absorbable foreign material, and has a low incidence of post-operative cerebrospinal fluid leakage.


Subject(s)
Adenoma/surgery , Hemostatics/therapeutic use , Neurosurgical Procedures/adverse effects , Pituitary Neoplasms/surgery , Aged , Bismuth/therapeutic use , Cerebrospinal Fluid Leak , Cerebrospinal Fluid Rhinorrhea/etiology , Cerebrospinal Fluid Rhinorrhea/therapy , Drug Combinations , Endoscopy , Fibrin Tissue Adhesive/therapeutic use , Gelatin Sponge, Absorbable/therapeutic use , Humans , Hydrocarbons, Iodinated/therapeutic use , Male , Neurosurgical Procedures/methods , Retrospective Studies , Sphenoid Sinus/surgery
14.
Hum Reprod ; 24(2): 360-6, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19010807

ABSTRACT

BACKGROUND: With >1% of US births occurring following use of assisted reproductive technology (ART), it is critical to examine whether ART is associated with birth defects. METHODS: We analyzed data from the National Birth Defects Prevention Study, a population-based, multicenter, case-control study of birth defects. We included mothers of fetuses or live-born infants with a major birth defect (case infants) and mothers who had live-born infants who did not have a major birth defect (control infants), delivered during the period October 1997-December 2003. We compared mothers who reported ART use (IVF or ICSI) with those who had unassisted conceptions. Multiple logistic regression was used to adjust for the following confounders: maternal race/ethnicity, maternal age, smoking and parity; we stratified by plurality. RESULTS: ART was reported by 1.1% of all control mothers, and by 4.5% of control mothers 35 years or older. Among singleton births, ART was associated with septal heart defects (adjusted odds ratio [aOR] = 2.1, 95% confidence intervals [CI] 1.1-4.0), cleft lip with or without cleft palate (aOR = 2.4, 95% CI 1.2-5.1), esophageal atresia (aOR = 4.5, 95% CI 1.9-10.5) and anorectal atresia (aOR = 3.7, 95% CI 1.5-9.1). Among multiple births, ART was not significantly associated with any of the birth defects studied. CONCLUSIONS: These findings suggest that some birth defects occur more often among infants conceived with ART. Although the mechanism is not clear, couples considering ART should be informed of all potential risks and benefits.


Subject(s)
Congenital Abnormalities/epidemiology , Reproductive Techniques, Assisted/adverse effects , Case-Control Studies , Female , Humans , Infant, Newborn , Pregnancy , Risk Factors , United States/epidemiology
15.
Clin Genet ; 75(2): 180-4, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19021635

ABSTRACT

We report Down syndrome (DS)-associated congenital gastrointestinal (GI) defects identified during a 15 year, population-based study of the etiology and phenotypic consequences of trisomy 21. Between 1989 and 2004, six sites collected DNA, clinical and epidemiological information on live-born infants with standard trisomy 21 and their parents. We used chi-squared test and logistic regression to explore relationships between congenital GI defects and infant sex, race, maternal age, origin of the extra chromosome 21, and presence of a congenital heart defect. Congenital GI defects were present in 6.7% of 1892 eligible infants in this large, ethnically diverse, population-based study of DS. Defects included esophageal atresia/tracheoesophageal fistula (0.4%), pyloric stenosis (0.3%), duodenal stenosis/atresia (3.9%), Hirschsprung disease (0.8%), and anal stenosis/atresia (1.0%). We found no statistically significant associations between these defects and the factors examined. Although not significant, esophageal atresia was observed more often in infants of younger mothers and Hispanics, Hirschsprung disease was more frequent in males and in infants of younger mothers and blacks, and anal stenosis/atresia was found more often among females and Asians.


Subject(s)
Down Syndrome/complications , Gastrointestinal Tract/abnormalities , Abnormalities, Multiple/etiology , Abnormalities, Multiple/genetics , Adult , Down Syndrome/pathology , Duodenal Obstruction/etiology , Esophageal Atresia/etiology , Ethnicity , Female , Hirschsprung Disease/etiology , Humans , Infant , Male , United States
17.
Am J Med Genet A ; 146A(18): 2385-9, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-18698630

ABSTRACT

There have been no large population-based studies of the prevalence of achondroplasia and thanatophroic dysplasia in the United States. This study compared data from seven population-based birth defects monitoring programs in the United States. We also present data on the association between older paternal age and these birth defects, which has been described in earlier studies. The prevalence of achondroplasia ranged from 0.36 to 0.60 per 10,000 livebirths (1/27,780-1/16,670 livebirths). The prevalence of thanatophoric dysplasia ranged from 0.21 to 0.30 per 10,000 livebirths (1/33,330-1/47,620 livebirths). In Texas, fathers that were 25-29, 30-34, 35-39, and > or =40 years of age had significantly increased rates of de novo achondroplasia among their offspring compared with younger fathers. The adjusted prevalence odds ratios were 2.8 (95% CI; 1.2, 6.7), 2.8 (95% CI; 1.0, 7.6), 4.9 (95% CI; 1.7, 14.3), and 5.0 (95% CI; 1.5, 16.1), respectively. Using the same age categories, the crude prevalence odds ratios for de novo cases of thanatophoric dysplasia in Texas were 5.8 (95% CI; 1.7, 9.8), 3.9 (95% CI; 1.1, 6.7), 6.1 (95% CI; 1.6, 10.6), and 10.2 (95% CI; 2.6, 17.8), respectively. These data suggest that thanatophoric dysplasia is one-third to one-half as frequent as achondroplasia. The differences in the prevalence of these conditions across monitoring programs were consistent with random fluctuation. Birth defects monitoring programs may be a good source of ascertainment for population-based studies of achondroplasia and thanatophoric dysplasia, provided that diagnoses are confirmed by review of medical records.


Subject(s)
Achondroplasia/epidemiology , Paternal Age , Thanatophoric Dysplasia/epidemiology , Adult , Confidence Intervals , Humans , Infant, Newborn , Male , Odds Ratio , Prevalence , Sentinel Surveillance , Texas/epidemiology , United States/epidemiology
18.
Inhal Toxicol ; 20(11): 1029-36, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18720170

ABSTRACT

Nonhuman primates are often the animal models of choice to study the infectivity and therapy of inhaled infectious agents. Most animal models for inhaled infectious diseases use aerosol/droplets generated by an atomization technique such as a Collison nebulizer that produces particles in the size range of 1 to 3 microm in diameter. There are few data in the literature on deposition patterns in monkeys. Our study was designed to measure the deposition pattern in monkeys using droplets having diameters of 2 and 5 microm using an exposure system designed to expose monkeys to aerosols of infectious agents. Six cynomolgus monkeys were exposed to droplets. The aerosol solution was generated from a Vero cell supernate containing DMEM + 10% fetal bovine serum tagged with Tc-99m radiolabel. Collison and Retec nebulizers were used to generate small and large droplets, respectively. The particle size (as determined from a cascade impactor) showed an activity median aerodynamic diameter (AMAD) of 2.3 and 5.1 microm for the Collison and Retec nebulizer, respectively. The animals were anesthetized, placed in a plethysmography box, and exposed to the aerosol. The deposition pattern was determined using a gamma camera. Deposition in the head airways was 39% and 58% for 2.3- and 5.1-microm particle aerosols, respectively, whereas the deposition in the deep lung was 12% and 8%, respectively. This information will be useful in developing animal models for inhaled infectious agents.


Subject(s)
Lung/metabolism , Technetium/metabolism , Administration, Inhalation , Aerosols , Animals , Cell Extracts/administration & dosage , Chlorocebus aethiops , Female , Lung/diagnostic imaging , Macaca fascicularis , Male , Nasal Mucosa/metabolism , Nebulizers and Vaporizers , Nose/diagnostic imaging , Particle Size , Radionuclide Imaging , Technetium/administration & dosage , Vero Cells
19.
Occup Environ Med ; 65(6): 420-9, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18032532

ABSTRACT

BACKGROUND: The use of chlorine for water disinfection results in the formation of numerous contaminants called disinfection by-products (DBPs), which may be associated with birth defects, including urinary tract defects. METHODS: We used Arkansas birth records (1998-2002) to conduct a population-based case-control study investigating the relationship between hypospadias and two classes of DBPs, trihalomethanes (THM) and haloacetic acids (HAA). We utilised monitoring data, spline regression and geographical information systems (GIS) to link daily concentrations of these DBPs from 263 water utilities to 320 cases and 614 controls. We calculated ORs for hypospadias and exposure to DBPs between 6 and 16 weeks' gestation, and conducted subset analyses for exposure from ingestion, and metrics incorporating consumption, showering and bathing. RESULTS: We found no increase in risk when women in the highest tertiles of exposure were compared to those in the lowest for any DBP. When ingestion alone was used to assess exposure among a subset of 40 cases and 243 controls, the intermediate tertiles of exposure to total THM and the five most common HAA had ORs of 2.11 (95% CI 0.89 to 5.00) and 2.45 (95% CI 1.06 to 5.67), respectively, compared to women with no exposure. When exposure to total THM from consumption, showering and bathing exposures was evaluated, we found an OR of 1.96 (95% CI 0.65 to 6.42) for the highest tertile of exposure and weak evidence of a dose-response relationship. CONCLUSIONS: Our results provide little evidence for a positive relationship between DBP exposure during gestation and an increased risk of hypospadias but emphasise the necessity of including individual-level data when assessing exposure to DBPs.


Subject(s)
Hypospadias/chemically induced , Prenatal Exposure Delayed Effects/chemically induced , Water Pollutants, Chemical/toxicity , Water Purification , Arkansas/epidemiology , Case-Control Studies , Chlorine/chemistry , Disinfection , Environmental Exposure/adverse effects , Environmental Exposure/analysis , Environmental Monitoring/methods , Epidemiological Monitoring , Female , Fluoroacetates/analysis , Fluoroacetates/toxicity , Humans , Hypospadias/epidemiology , Infant, Newborn , Male , Maternal-Fetal Exchange , Pregnancy , Trihalomethanes/analysis , Trihalomethanes/toxicity , Water Pollutants, Chemical/analysis , Water Supply/analysis
20.
J Laryngol Otol ; 121(12): e23, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18034914

ABSTRACT

OBJECTIVE: We report a case of post-partum surgical cervical emphysema, which is a rare but well recognised complication of labour. By reporting the first case in the ENT literature, we aim to raise awareness of this complication, particularly amongst trainees, to ensure that patients are managed most appropriately. CASE REPORT: A 36-year-old, primigravida woman developed neck swelling and odynophagia post-partum. Surgical cervical emphysema was palpated, with further examination excluding pneumomediastinum and pneumothorax. The patient was managed conservatively, with complete resolution of symptoms within a week. CONCLUSIONS: Surgical cervical emphysema, pneumothorax and pneumomediastinum are all well recognised post-partum complications. The vast majority of cases do not present with respiratory or cardiac compromise and can be appropriately managed conservatively, with expectation of resolution in a fortnight. There is no evidence that such patients are at increased risk during subsequent pregnancies.


Subject(s)
Neck/diagnostic imaging , Puerperal Disorders/diagnostic imaging , Subcutaneous Emphysema/diagnostic imaging , Subcutaneous Emphysema/etiology , Adult , Female , Humans , Radiography , Remission, Spontaneous
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