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2.
BJS Open ; 5(2)2021 03 05.
Article in English | MEDLINE | ID: mdl-33839749

ABSTRACT

BACKGROUND: Ventra hernias are increasing in prevalence and many recur despite attempted repair. To date, much of the literature is underpowered and divergent. As a result there is limited high quality evidence to inform surgeons succinctly which perioperative variables influence postoperative recurrence. This systematic review aimed to identify predictors of ventral hernia recurrence. METHODS: PubMed was searched for studies reporting prognostic data of ventral hernia recurrence between 1 January 1995 and 1 January 2018. Extracted data described hernia type (primary/incisional), definitions of recurrence, methods used to detect recurrence, duration of follow-up, and co-morbidity. Data were extracted for all potential predictors, estimates and thresholds described. Random-effects meta-analysis was used. Bias was assessed with a modified PROBAST (Prediction model Risk Of Bias ASsessment Tool). RESULTS: Screening of 18 214 abstracts yielded 274 individual studies for inclusion. Hernia recurrence was defined in 66 studies (24.1 per cent), using 41 different unstandardized definitions. Three patient variables (female sex, age 65 years or less, and BMI greater than 25, 30, 35 or 40 kg/m2), five patient co-morbidities (smoking, diabetes, chronic obstructive pulmonary disease, ASA grade III-IV, steroid use), two hernia-related variables (incisional/primary, recurrent/primary), six intraoperative variables (biological mesh, bridged repair, open versus laparoscopic surgery, suture versus mesh repair, onlay/retrorectus, intraperitoneal/retrorectus), and six postoperative variables (any complication, surgical-site occurrence, wound infection, seroma, haematoma, wound dehiscence) were identified as significant prognostic factors for hernia recurrence. CONCLUSION: This study summarized the current evidence base for predicting ventral hernia recurrence. Results should inform best practice and future research.


Subject(s)
Hernia, Ventral/surgery , Herniorrhaphy/methods , Laparoscopy , Surgical Mesh , Suture Techniques , Herniorrhaphy/instrumentation , Humans , Randomized Controlled Trials as Topic , Recurrence , Treatment Outcome
3.
World J Surg ; 43(2): 396-404, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30187090

ABSTRACT

Large ventral hernias are a significant surgical challenge. "Loss of domain" (LOD) expresses the relationship between hernia and abdominal volume, and is used to predict operative difficulty and success. This systematic review assessed whether different definitions of LOD are used in the literature. The PubMed database was searched for articles reporting large hernia repairs that explicitly described LOD. Two reviewers screened citations and extracted data from selected articles, focusing on the definitions used for LOD, study demographics, study design, and reporting surgical specialty. One hundred and seven articles were identified, 93 full-texts examined, and 77 were included in the systematic review. Sixty-seven articles were from the primary literature, and 10 articles were from the secondary literature. Twenty-eight articles (36%) gave a written definition for loss of domain. These varied and divided into six broad groupings; four described the loss of the right of domain, six described abdominal strap muscle contraction, five described the "second abdomen", five describing large irreducible hernias. Six gave miscellaneous definitions. Two articles gave multiple definitions. Twenty articles (26%) gave volumetric definitions; eight used the Tanaka method [hernia sac volume (HSV)/abdominal cavity volume] and five used the Sabbagh method [(HSV)/total peritoneal volume]. The definitions used for loss of domain were not dependent on the reporting specialty. Our systematic review revealed that multiple definitions of loss of domain are being used. These vary and are not interchangeable. Expert consensus on this matter is necessary to standardise this important concept for hernia surgeons.


Subject(s)
Hernia, Ventral/surgery , Abdominal Cavity/surgery , Humans
4.
Musculoskelet Surg ; 100(3): 213-216, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27650374

ABSTRACT

PURPOSE: Avascular necrosis (AVN) of the humeral head is a devastating complication of proximal humeral fracture (PHF) that often results in long-term morbidity for the patient. Rates of AVN depend on the number of fracture fragments and are highly variable. The literature suggests that timely stable and anatomic reduction may decrease the rate at which AVN develops after PHF. To our knowledge, there is no literature published investigating a temporal relationship between the timing of PHF fixation and rates of AVN. METHODS: Operative records of one orthopedic trauma surgeon were used to identify patients that underwent open reduction internal fixation for PHF at our institution between 2007 and 2012. Radiographs at presentation were reviewed and used to classify the fractures into two, three or four parts. Date and time of the initial radiograph were recorded as were the date and time of available intra-operative fluoroscopic images. The time from presentation radiograph to operative fixation was calculated (hours). Available follow-up plain films were then reviewed and evaluated for the presence or absence of humeral head AVN. RESULTS: Time to surgery (less than or greater than 72 h) and patient age did not correlate with development of AVN after PHF (p > 0.26). Notably, the number of fracture fragments did influence the rate of AVN identified in patients with PHF (p = 0.002). CONCLUSION: Early operative intervention does not appear to decrease the rate of development of avascular necrosis after PHF.


Subject(s)
Bone Plates , Fracture Fixation, Internal , Osteonecrosis/diagnostic imaging , Osteonecrosis/surgery , Radiography , Shoulder Fractures/diagnostic imaging , Shoulder Fractures/surgery , Adolescent , Adult , Aged , Follow-Up Studies , Fracture Fixation, Internal/methods , Fracture Healing , Humans , Middle Aged , Retrospective Studies , Treatment Outcome
5.
J Phys Chem A ; 119(50): 12339-48, 2015 Dec 17.
Article in English | MEDLINE | ID: mdl-26469080

ABSTRACT

The room-temperature photoabsorption spectra of a number of linear alkynes with internal triple bonds (e.g., 2-butyne, 2-pentyne, and 2- and 3-hexyne) show similar resonances just above the lowest ionization threshold of the neutral molecules. These features result in a substantial enhancement of the photoabsorption cross sections relative to the cross sections of alkynes with terminal triple bonds (e.g., propyne, 1-butyne, 1-pentyne, ...). Based on earlier work on 2-butyne [ Xu et al., J. Chem. Phys. 2012, 136, 154303 ], these features are assigned to excitation from the neutral highest occupied molecular orbital (HOMO) to a shape resonance with g (l = 4) character and approximate π symmetry. This generic behavior results from the similarity of the HOMOs in all internal alkynes, as well as the similarity of the corresponding gπ virtual orbital in the continuum. Theoretical calculations of the absorption spectrum above the ionization threshold for the 2- and 3-alkynes show the presence of a shape resonance when the coupling between the two degenerate or nearly degenerate π channels is included, with a dominant contribution from l = 4. These calculations thus confirm the qualitative arguments for the importance of the l = 4 continuum near threshold for internal alkynes, which should also apply to other linear internal alkynes and alkynyl radicals. The 1-alkynes do not have such high partial waves present in the shape resonance. The lower l partial waves in these systems are consistent with the broader features observed in the corresponding spectra.

6.
J Chem Phys ; 143(3): 034304, 2015 Jul 21.
Article in English | MEDLINE | ID: mdl-26203024

ABSTRACT

The absolute photoabsorption cross sections of 1- and 2-butyne have been recorded at high resolution by using the vacuum-ultraviolet Fourier-Transform spectrometer at the SOLEIL Synchrotron. Both spectra show more resolved structure than previously observed, especially in the case of 2-butyne. In this work, we assess the potential importance of Rydberg states with higher values of orbital angular momentum, l, than are typically observed in photoabsorption experiments from ground state molecules. We show how the character of the highest occupied molecular orbitals in 1- and 2-butyne suggests the potential importance of transitions to such high-l (l = 3 and 4) Rydberg states. Furthermore, we use theoretical calculations of the partial wave composition of the absorption cross section just above the ionization threshold and the principle of continuity of oscillator strength through an ionization threshold to support this conclusion. The new absolute photoabsorption cross sections are discussed in light of these arguments, and the results are consistent with the expectations. This type of argument should be valuable for assessing the potential importance of different Rydberg series when sufficiently accurate direct quantum chemical calculations are difficult, for example, in the n ≥ 5 manifolds of excited states of larger molecules.

7.
J Chem Phys ; 141(11): 114303, 2014 Sep 21.
Article in English | MEDLINE | ID: mdl-25240354

ABSTRACT

The absolute photoabsorption cross section of propyne was recorded between 62,000 and 88,000 cm(-1) by using the vacuum-ultraviolet, Fourier-transform spectrometer at the Synchrotron Soleil. This cross section spans the region including the lowest Rydberg bands and extends above the Franck-Condon envelope for ionization to the ground electronic state of the propyne cation, X̃(+). Room-temperature spectra were recorded in a flowing cell at 0.9 cm(-1) resolution, and jet-cooled spectra were recorded at 1.8 cm(-1) resolution and a rotational temperature of ~100 K. The reduced widths of the rotational band envelopes in the latter spectra reveal new structure and simplify a number of assignments. Although nf Rydberg series have not been assigned previously in the photoabsorption spectrum of propyne, arguments are presented for their potential importance, and the assignment of one nf series is proposed. As expected from previous photoelectron spectra, Rydberg series are also observed above the adiabatic ionization threshold that converge to the v3(+) = 1 and 2 levels of the C≡C stretching vibration.

8.
Phys Chem Chem Phys ; 16(39): 21629-44, 2014 Oct 21.
Article in English | MEDLINE | ID: mdl-25196806

ABSTRACT

The recently introduced synchrotron radiation-based Fourier transform spectroscopy has been employed to study the excited electronic states of thiophene. A highly resolved photoabsorption spectrum has been measured between ∼5 and 12.5 eV, providing a wealth of new data. High-level ab initio computations have been performed using the second-order algebraic-diagrammatic construction (ADC(2)) polarization propagator approach, and the equation-of-motion coupled-cluster (EOM-CC) method at the CCSD and CC3 levels, to guide the assignment of the spectrum. The adiabatic energy corrections have been evaluated, thereby extending the theoretical study beyond the vertical excitation picture and leading to a significantly improved understanding of the spectrum. The low-lying π→π* and π→σ* transitions result in prominent broad absorption bands. Two strong Rydberg series converging onto the X(~)(2)A2 state limit have been assigned to the 1a2→npb1(1)B2 and the 1a2→nda2(1)A1 transitions. A second, and much weaker, d-type series has been assigned to the 1a2→ndb1(1)B2 transitions. Excitation into some of the Rydberg states belonging to the two strong series gives rise to vibrational structure, most of which has been interpreted in terms of excitations of the totally symmetric ν4 and ν8 modes. One Rydberg series, assigned to the 3b1→nsa1(1)B1 transitions, has been identified converging onto the Ã(2)B1 state limit, and at higher energies Rydberg states converging onto the B(~)(2)A1 state limit could be identified. The present spectra reveal highly irregular vibrational structure in certain low energy absorption bands, and thus provide a new source of information for the rapidly developing studies of excited state non-adiabatic dynamics and photochemistry.

9.
Ann Oncol ; 23(12): 3075-3081, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22767584

ABSTRACT

BACKGROUND: Cyclophosphamide-methotrexate-5-fluorouracil (CMF) is often selected as adjuvant chemotherapy for older patients with early-stage breast cancer due to perceived superior tolerability. We sought to measure persistence with CMF, adherence to oral cyclophosphamide, and the association of these with toxic effects. PATIENTS AND METHODS: CALGB 49907 was a randomized trial comparing standard chemotherapy (CMF or AC, provider/patient choice) with capecitabine in patients aged ≥65 with stage I-IIIB breast cancer. Those randomized to standard therapy and choosing CMF were prescribed oral cyclophosphamide 100 mg/m(2) for 14 consecutive days in six 28-day cycles. Persistence was defined as being prescribed six cycles of at least one of the three CMF drugs. Adherence was the number of cyclophosphamide doses that women reported they had taken divided by the number prescribed. Persistence and adherence were based on case report forms and medication calendars. RESULTS: Of 317 randomized to standard chemotherapy, 133 received CMF. Median age was 73 (range 65-88). Seventy-one percent submitted at least one medication calendar; 65% persisted with CMF. Non-persistence was associated with node negativity (P = 0.019), febrile neutropenia (P = 0.002), and fatigue (P = 0.044). Average adherence was 97% during prescribed cycles. CONCLUSIONS: Self-reported adherence to cyclophosphamide was high, but persistence was lower, which may be attributable to toxic effects.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Medication Adherence , Patient Compliance , Age Factors , Aged , Aged, 80 and over , Capecitabine , Chemotherapy, Adjuvant/adverse effects , Cyclophosphamide/adverse effects , Cyclophosphamide/therapeutic use , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Female , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Fluorouracil/therapeutic use , Humans , Methotrexate/adverse effects , Methotrexate/therapeutic use
10.
Br J Radiol ; 85(1016): 1085-92, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22422379

ABSTRACT

OBJECTIVE: To compare a 2 day bowel preparation regime of barium, iodine and a mild stimulant laxative with a 1 day iodine-only regime for CT colonography (CTC). METHODS: 100 consecutive patients underwent CTC. The first 50 patients (Regime 1) ingested 1 bisacodyl tablet twice a day 3 days before CTC and 1 dose each of 50 ml of barium and 20 ml of iodinated contrast per day starting 2 days before CTC. The second 50 patients (Regime 2) ingested 3 doses of iodinated contrast over 24 h prior to CTC. Volumes of residual stool and fluid, and the effectiveness of stool and fluid tagging, were graded according to methods established by Taylor et al (Taylor S, Slaker A, Burling D, Tam E, Greenhalgh R, Gartner L, et al. CT colonography: optimisation, diagnostic performance and patient acceptability of reduced-laxative regimens using barium-based faecal tagging. Eur Radiol 2008; 18: 32-42). A 3 day low-residue diet was taken by both cohorts. Questionnaires rating the side-effects and burden of the bowel preparation were compared to a control cohort of patients undergoing barium enema. RESULTS: The proportion of colons producing none/scattered stool (score 1) was 90.3% with Regime 1 and 65.0% with Regime 2 (p<0.005). Any residual stool was significantly better tagged with Regime 1 (score 5), with 91.7% of Regime 1 exhibiting optimum tagging vs 71.3% of Regime 2 (p<0.05). No significant differences in side-effects between the bowel preparation regimes for CTC were elicited. Bowel preparation for barium enema was tolerated significantly worse than both of the CTC bowel preparation regimes. CONCLUSION: Regime 1, containing a 3 day preparation of a mild laxative, barium and iodine, produced a significantly better prepared colon, with no difference in patient acceptability.


Subject(s)
Cathartics/administration & dosage , Colonography, Computed Tomographic/methods , Contrast Media/administration & dosage , Laxatives/administration & dosage , Aged , Analysis of Variance , Anemia, Iron-Deficiency/etiology , Barium Sulfate/administration & dosage , Bisacodyl/administration & dosage , Body Fluids , Colonography, Computed Tomographic/standards , Colorectal Neoplasms/diagnosis , Diatrizoate Meglumine/administration & dosage , Drug Combinations , Enema/methods , Feces , Female , Gastrointestinal Hemorrhage/etiology , Humans , Iodine/administration & dosage , Male , Patient Satisfaction , Prospective Studies , Surveys and Questionnaires
11.
Soc Stud Sci ; 41(5): 667-90, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22164720

ABSTRACT

When scientists from two or more disciplines work together on related problems, they often face what we call 'science friction'. As science becomes more data-driven, collaborative, and interdisciplinary, demand increases for interoperability among data, tools, and services. Metadata--usually viewed simply as 'data about data', describing objects such as books, journal articles, or datasets--serve key roles in interoperability. Yet we find that metadata may be a source of friction between scientific collaborators, impeding data sharing. We propose an alternative view of metadata, focusing on its role in an ephemeral process of scientific communication, rather than as an enduring outcome or product. We report examples of highly useful, yet ad hoc, incomplete, loosely structured, and mutable, descriptions of data found in our ethnographic studies of several large projects in the environmental sciences. Based on this evidence, we argue that while metadata products can be powerful resources, usually they must be supplemented with metadata processes. Metadata-as-process suggests the very large role of the ad hoc, the incomplete, and the unfinished in everyday scientific work.


Subject(s)
Climate Change , Cooperative Behavior , Information Dissemination , Interdisciplinary Communication , Science , Ecology , Humans
12.
Chem Commun (Camb) ; 47(47): 12610-2, 2011 Dec 21.
Article in English | MEDLINE | ID: mdl-22051794

ABSTRACT

We report a novel aluminium-ion rechargeable battery comprised of an electrolyte containing AlCl(3) in the ionic liquid, 1-ethyl-3-methylimidazolium chloride, and a V(2)O(5) nano-wire cathode against an aluminium metal anode. The battery delivered a discharge capacity of 305 mAh g(-1) in the first cycle and 273 mAh g(-1) after 20 cycles, with very stable electrochemical behaviour.

13.
Eur J Cancer ; 47(5): 683-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21324674

ABSTRACT

BACKGROUND: Chemotherapy-induced ovarian failure (CIOF) is a frequent side-effect of adjuvant chemotherapy that results in rapid bone loss. We hypothesised that zoledronic acid (ZA), a third-generation amino bisphosphonate, would prevent bone loss in premenopausal women who developed CIOF. METHODS: Women (439) were randomised to intravenous (i.v.) ZA 4 mg every 3 months for 2 years starting within 1-3 months after randomization (arm A) or 1 year after randomization (arm B, controls). CIOF was prospectively defined as ≥ 3 months of amenorrhoea, follicle-stimulating hormone (FSH) ≥ 30 MIU/ml and non-pregnant at 1 year. The primary end-point was the percentage change in bone mineral density (BMD) in the lumbar spine (LS) from baseline to 12 months in the ZA and in control groups in women who developed CIOF; the secondary end-point was BMD in LS at 3 years in all randomised women. FINDINGS: One hundred and fifty (56%) met the definition of CIOF at 1 year. Overall, grade 3 toxicities of ZA were fatigue (1%) arthralgias (21%) and pain (84%). The median percent change (interquartile range, IQR) at 1 year was +1.2% (-0.5% to +2.8%) and -6.7% (-9.7% to -2.9%) p<0.001 and at 3 years was +1.0% (-1.6% to +5.2%) and -0.5% (-3.7% to +3.2%) p=0.019 in arms A and B, respectively. INTERPRETATION: ZA every 3 months is well tolerated and prevents rapid bone loss in premenopausal women that develop CIOF. Giving ZA with rather than 1 year after the start of adjuvant chemotherapy is the preferred sequence to prevent bone loss.


Subject(s)
Antineoplastic Agents/adverse effects , Bone Density Conservation Agents/administration & dosage , Bone Density/drug effects , Diphosphonates/administration & dosage , Imidazoles/administration & dosage , Premenopause , Primary Ovarian Insufficiency/chemically induced , Adult , Bone Density Conservation Agents/adverse effects , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant/adverse effects , Diphosphonates/adverse effects , Fatigue/chemically induced , Female , Fever/chemically induced , Humans , Imidazoles/adverse effects , Infusions, Intravenous , Middle Aged , Pain/chemically induced , Prospective Studies , Zoledronic Acid
14.
J Wound Care ; 19(10): 457-60, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20948495

ABSTRACT

Hidradenitis suppurativa (HS) is a frustrating disease to treat for both the patient and the practitioner. In severe cases, aggressive management will often have a more tolerable outcome. We present the case of a 46-year-old gentleman with a long-standing history of severe HS, who was treated successfully with wide surgical excision, followed by a full-thickness skin graft and negative pressure wound therapy (both pre- and post-operatively). A review of the literature revealed few reports of HS treatment using these sequential steps.


Subject(s)
Hidradenitis Suppurativa/therapy , Negative-Pressure Wound Therapy/methods , Biopsy , Hidradenitis Suppurativa/diagnosis , Hidradenitis Suppurativa/epidemiology , Hidradenitis Suppurativa/etiology , Humans , Male , Middle Aged , Perioperative Care/methods , Severity of Illness Index , Skin Care/methods , Skin Transplantation , Treatment Outcome
16.
Bone Marrow Transplant ; 44(6): 353-9, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19289999

ABSTRACT

We studied the feasibility and efficacy of a two-step approach to Auto-SCT for patients with AML in second remission. Step 1 consisted of consolidation chemotherapy using cytarabine 2000 mg/m(2) i.v. every 12 h for 4 days plus etoposide 40 mg/kg total dose by continuous i.v. infusion over the same 4 days. PBSC were collected after G-CSF stimulation during recovery from this chemotherapy. Step 2, auto-SCT, used a preparative regimen of oral BU 16 mg/kg over 4 days followed by etoposide 60 mg/kg i.v. Of the 50 patients entered on Step 1, two died from treatment complications, and seven failed to proceed to transplantation. A median CD34+ cell dose of 5.9 x 10(6)/kg was collected in a median of three collections. With a median follow-up of 8.2 years, 5-year disease-free survival (DFS) is 28%. The most important prognostic factor was cytogenetics, with acute promyelocytic leukemia (APL) patients having a 5-year DFS of 67% compared with 16% for others. We conclude that this two-step approach to autologous transplantation produces good CD34+ mobilization and that this approach has cured some patients. Results in patients with APL are especially promising.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Antineoplastic Agents, Phytogenic/therapeutic use , Cytarabine/therapeutic use , Etoposide/therapeutic use , Leukemia, Myeloid, Acute/therapy , Peripheral Blood Stem Cell Transplantation , Adult , Aged , Aging , Antigens, CD34/analysis , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/adverse effects , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Agents, Phytogenic/adverse effects , Combined Modality Therapy/adverse effects , Cytarabine/administration & dosage , Cytarabine/adverse effects , Disease-Free Survival , Etoposide/administration & dosage , Etoposide/adverse effects , Female , Humans , Ideal Body Weight , Infusions, Intravenous , Kaplan-Meier Estimate , Leukemia, Myeloid, Acute/classification , Leukemia, Myeloid, Acute/mortality , Male , Middle Aged , Peripheral Blood Stem Cell Transplantation/adverse effects , Remission Induction , Transplantation, Autologous , Treatment Outcome , Treatment Refusal , Young Adult
17.
J Dent Res ; 86(6): 556-9, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17525357

ABSTRACT

Osteoclasts play a vital role in orthodontic tooth movement. Transactivation of nuclear factor kappaB (NFkappaB) by phosphorylation of the p65 component of NFkappaB at amino acid 536 (p65*(536)) plays a role in osteoclast differentiation stimulated by receptor activator of nuclear factor kappaB-ligand (RANK-L). We hypothesized that this transactivation pathway might be involved in the responses of alveolar bone cells during orthodontic tooth movement. We detected sharp increases in the levels of p65*(536) 3 and 12 hrs after the application of orthodontic stimuli in rats. In cell culture, osteoclast-like cells displayed no changes in p65*(536) in response to RANK-L, but levels rapidly increased after the cells were mechanically scraped. We conclude that p65*(536) is produced rapidly in response to orthodontic stimuli and mechanical insults, and may be important in bone remodeling associated with orthodontic tooth movement.


Subject(s)
Osteoclasts/metabolism , Tooth Movement Techniques , Transcription Factor RelA/metabolism , Alveolar Process/cytology , Animals , Biomechanical Phenomena , Cell Differentiation/genetics , Cell Line , Electrophoresis, Polyacrylamide Gel , Immunoblotting , Immunoenzyme Techniques , Immunohistochemistry , Male , Mice , Phosphorylation , RANK Ligand/metabolism , Rats , Rats, Sprague-Dawley , Stress, Mechanical , Time Factors , Transcription Factor RelA/analysis , Transcriptional Activation/genetics
18.
Eur Phys J E Soft Matter ; 20(1): 109-17, 2006 May.
Article in English | MEDLINE | ID: mdl-16733645

ABSTRACT

Ionically modified silica nanoparticles with large counter anions (sulfonate, isostearate) at two silica volume fractions (13 and 27%) form a viscous fluid and a glass but not crystalline solids. Dielectric spectroscopy, Brillouin scattering and shear rheometry were employed to investigate these new nanoparticle-based fluids. The glass transition temperature and hence the local dynamics are governed by the large counter anions, whereas the flow properties can be controlled by the spatial correlation between the nanoparticles, e.g. by tuning the volume fraction of hard cores and local interactions between segments in the soft corona. Liquid-like ordering of the cores was revealed by X-ray scattering and found to influence significantly the macroscopic flow properties of these salts.


Subject(s)
Nanostructures/chemistry , Silicon Dioxide/chemistry , Crystallization , Particle Size , Phase Transition , Rheology , Scattering, Radiation , Spectrum Analysis , Surface Properties , X-Ray Diffraction
19.
Eur Respir J ; 26(6): 1080-5, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16319339

ABSTRACT

Long-term survival in lung transplantation is limited by the development of obliterative bronchiolitis, a condition characterised by inflammation, epithelial injury, fibroproliferation and obliteration of bronchioles leading to airflow obstruction. To investigate the role of the bronchial epithelium in the pathogenesis of obliterative bronchiolitis the current study aimed to establish primary bronchial epithelial cell cultures (PBEC) from lung allografts. Four to six bronchial brushings were obtained from sub-segmental bronchi of lung allografts. Cells were seeded onto collagen-coated plates and grown to confluence in bronchial epithelial growth medium. Bronchial brushings (n=33) were obtained from 27 patients. PBECs were grown to confluence from 12 out of 33 (39%) brushings. Failure to reach confluence was due to early innate infection. Bacteria were usually isolated from both bronchoalveolar lavage and culture media, but a separate population was identified in culture media only. Primary culture of bronchial epithelial cells from lung transplant recipients is feasible, despite a high rate of early, patient-derived infection. Latent infection of the allograft, identified only by bronchial brushings, may itself be a persistent stimulus for epithelial injury. This technique facilitates future mechanistic studies of airway epithelial responses in the pathogenesis of obliterative bronchiolitis.


Subject(s)
Bronchiolitis Obliterans/pathology , Bronchoalveolar Lavage Fluid/cytology , Epithelial Cells/pathology , Lung Transplantation/adverse effects , Adolescent , Adult , Biopsy, Needle , Cells, Cultured , Chi-Square Distribution , Female , Graft Rejection , Graft Survival , Humans , Immunohistochemistry , Lung Transplantation/methods , Male , Middle Aged , Postoperative Complications/pathology , Probability , Respiratory Mucosa/pathology , Risk Factors , Sampling Studies , Sensitivity and Specificity , Statistics, Nonparametric , Transplantation, Homologous
20.
J Pediatr Surg ; 40(9): 1482-3, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16150353

ABSTRACT

We report a case of a successful surgical resection of a Wilms' tumor in the right kidney with a coincidental preoperative imaging finding of a left-sided inferior vena cava. To our knowledge, these 2 conditions occurring together has not been previously reported in literature. Diagnostic features and the value of magnetic resonance imaging are emphasized. We also review the literature of major venous anomalies and their influence on surgical procedures carried out on such patients.


Subject(s)
Kidney Neoplasms/surgery , Vena Cava, Inferior/abnormalities , Wilms Tumor/surgery , Child , Functional Laterality , Humans , Kidney Neoplasms/pathology , Magnetic Resonance Imaging , Male , Vena Cava, Inferior/pathology , Vena Cava, Inferior/surgery , Wilms Tumor/pathology
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