Effects of Static Electric Fields on the Excitations of Silver Nanowire Dimers.

We theoretically studied the introduction of static electric fields to Ag10 nanowire dimer systems, including the effects of this field on optical absorption characteristics and the orbitals responsible for these excitations. Linear-response time-dependent density functional theory computations were performed on three distinct dimer systems: end-to-end, parallel, and 90° angle dimer systems separated by a closest interparticle distance of 7.0 Å. The calculations were performed in the presence of a 0.1 V/Å electric field strength applied in the z and y directions. The orientation of the dimer system and the direction of the applied static electric field each play a significant role in the resulting absorption spectra and the electronic structure of the nanowires. As a result, a dimer system can exhibit a blue shift for the longitudinal excitation and a red shift for the transverse excitation in the presence of one direction of the static electric field but not for the other direction. Notably, the electron density shifts from one nanowire to the other in the presence of the static electric field. Changes in optical characteristics and electronic structure suggest that the usage of a static electric field with a particular spatial configuration of nanowires provides a way to tune the optical properties of the system.

Education: A compassionate use of cefiderocol to treat osteomyelitis caused by an XDR Pseudomonas aeruginosa.

We report a 59-year-old male with left leg osteomyelitis caused by an XDR Pseudomonas aeruginosa strain following a road traffic accident. Limited treatment options and adverse antimicrobial reaction led to consideration of cefiderocol together with appropriate surgical intervention. Improved bony remodelling over the tibia and fibula was observed with good bony alignment and no adverse features. Physiotherapy support was continued for 4 months following treatment, which resulted in good functional mobility, improved proprioception and full ability to bear weight. This case also adds to multiple reports that describe safe and successful use of cefiderocol to treat MDR, aerobic Gram-negative infections.

Anti-viral therapy for prevention of perinatal HBV transmission: extending therapy beyond birth does not protect against post-partum flare.

BACKGROUND: Antepartum anti-viral therapy (AVT) is often administered to prevent perinatal transmission of hepatitis B virus (HBV) infection. Little is known about the effect of AVT on post-partum flare rates and severity. AIM: To examine whether extending AVT beyond birth influences the post-partum course. METHODS: One hundred and one pregnancies in 91 women with HBV DNA levels ≥log 7 IU/mL were included. AVT (initially lamivudine, later tenofovir disoproxil fumarate) was commenced from 32 weeks gestation and stopped soon after birth and at 12 weeks post-partum. Outcomes according to post-partum treatment duration were examined: Group 1 = AVT ≤4 weeks (n = 44), Group 2 = AVT >4 weeks (n = 43), Group 3 = no AVT (n = 14). RESULTS: The majority of women were HBeAg+ (97%), median age 29 years, baseline HBV DNA log 8.0 IU/mL and follow-up 48 weeks post-partum. Post-partum treatment duration was 2 weeks for Group 1 and 12 weeks for Group 2, P < 0.01. Flare rates were not significantly different: Group 1 = 22/44 (50%), Group 2 = 17/43 (40%) and Group 3 = 4/14 (29%), P = 0.32. Onset of flare was similar at 8/10/9 weeks post-partum for Groups 1/2/3 respectively, P = 0.34. The majority of flares spontaneously resolved. HBeAg seroconversion (n = 1/5/1 in Groups 1/2/3, P = 0.27) was not associated with treatment duration or the occurrence of a post-partum flare. CONCLUSIONS: Post-partum flares are common and usually arise early after delivery. They are often mild in severity and most spontaneously resolve. Extending anti-viral therapy does not protect against post-partum flares or affect HBeAg seroconversion rates.

Matching the numerator with an appropriate denominator to demonstrate low amputation incidence associated with a London hospital multidisciplinary diabetic foot clinic.

AIMS: To establish a method to assess amputation incidence that addresses the problems matching a numerator with an appropriate denominator in London and to demonstrate low amputation incidence associated with the activity of our multidisciplinary diabetic foot clinic. METHODS: Hospital-coded inpatient data was examined to derive the numerator: the number of non-traumatic amputations performed on subjects with diabetes each financial year where the Primary Care Trust commissioner code was our main local Primary Care Trust. Denominators were derived from the main local Primary Care Trust's Quality and Outcomes Framework data sets. Not all Primary Care Trust subjects with diabetes receive inpatient care at our hospital, so that the denominators were corrected for the hospital's percentage market share for the provision of inpatient diabetes care for the Primary Care Trust each financial year, derived from the Dr Foster database. RESULTS: Between April 2004 and April 2009, 44 Primary Care Trust subjects with diabetes underwent 34 minor and 10 major amputations at the hospital. Although the Primary Care Trust populations with and without diabetes increased, the hospital's Primary Care Trust percentage market share decreased, so that overall denominators decreased. The mean annual incidence of minor, major and total amputations over the five financial years was 14.7, 4.2 and 18.9 per 10 000 subjects with diabetes,respectively, and 3.9, 1.1 and 5.0 per 100 000 of the general population, respectively. CONCLUSIONS: We report for the first time amputation incidence in a London population. Acknowledging the limitations of accurately defining incidence in London, we demonstrate low amputation incidence associated with our multidisciplinary diabetic foot clinic.

Conservative management of diabetic forefoot ulceration complicated by underlying osteomyelitis: the benefits of magnetic resonance imaging.

AIMS: To assess efficacy of conservative management of neuropathic forefoot ulcers with underlying osteomyelitis in subjects with diabetes when magnetic resonance imaging (MRI) is used to confirm or establish diagnosis and to guide antibiotic duration. METHODS: A retrospective cohort study over 6 years assessing rates of ulcer healing, relapse and amputation. Antibiotics were continued for 3-month cycles with interval MRI: if the lesion had healed and bone signal change resolved or improved, antibiotics were discontinued; if the lesion had not healed or there was no difference in bone signal change, antibiotics were continued for a further 3-month cycle; clinical or radiological deterioration resulted in endoluminal or open vascular surgical intervention where appropriate, or digital or more proximal amputation. RESULTS: There were 53 episodes in 47 subjects (mean +/- sd age 62 +/- 13 years, duration of diabetes 19 +/- 13 years, glycated haemoglobin 8.4 +/- 1.6%; six with Type 1 diabetes and seven with end-stage renal failure). Successful healing without relapse was achieved in 40 episodes (75%) [median (range) duration of antibiotics 6 (3-12) months and follow-up post-cessation of antibiotics 15 (3-58) months]. Relapse occurred in six episodes (13%) at 31 (2-38) months post-cessation of antibiotics. There were one major (2%) and eight minor (15%) amputations. Five subjects have died (11%), all without foot ulcers. CONCLUSIONS: High rates of healing and low rates of amputation were achieved. The use of MRI was associated with long courses of antibiotics, but particularly low relapse rate.

Alcohol and tobacco use among males in two districts in Sri Lanka.

OBJECTIVES: To investigate the prevalence and consumption of tobacco and alcohol among males in the Colombo and Polonnaruwa districts. DESIGN: A cross-sectional study based on multistage cluster sampling was carried out in four Medical Officer of Health (MOH) areas in the Colombo (urban) and Polonnaruwa (rural) districts to assess the prevalence of tobacco and alcohol use. The Public Health Midwife areas were considered as primary clusters. The sample consisted of males over 18 years. There were 1318 from the Colombo District and 1366 from the Polonnaruwa District. The quantity frequency method was used to assess consumption. RESULTS: Abstinence was significantly higher in the rural areas (75.2%) compared to urban areas (56.6%) (p < 0.001). Prevalence of current drinking in the urban areas (32.9%) was significantly higher than in rural areas (20.8%) (p < 0.001). Alcohol consumption in the urban areas (33.1 units/week) was significantly higher than in rural areas (20.9) (p < 0.004). 51.6/1000 males in the urban areas and 14.6/1000 males in rural areas consumed daily. The prevalence of current smoking was also higher in the urban areas (29.9%) than (p = 0.052) in rural areas (24.4%). CONCLUSION: High-risk alcohol consumption was prevalent especially in urban areas as indicated by the mean alcohol consumption and number who consumed spirits daily. The prevalence of smoking is much lower than in many Asian countries but similar to western Europe.

Sentinel lymph node biopsy in the Sultanate of Oman.

OBJECTIVE: To establish the feasibility of newly started sentinel lymph node (SLN) biopsy in our center at the Royal Hospital in the Sultanate of Oman. METHODS: Twenty five patients with Breast cancer and melanoma were staged with sentinel lymph node (SLN) biopsy, followed by Axillary lymph Node Dissection (ALND). Axillary SLN were detected by injection of blue dye alone or with radioisotope. Intraoperatively, a gamma probe detector identified the isotope-labeled SLN. Two patients underwent preoperative lymphoscintigraphy. The SLNs were examined histologically by hematoxylin-eosin staining and, if negative by this method an immunohistochemical staining (IHC) was done. RESULTS: The only failure to detect inguinal SLN was one case after neoadjuvant chemotherapy. Total detection rate of SLN was of 96%. Metastatic spread occurred in 11 patients of these 9 had other lymph node (LN) involved. Nine patients had no SLN involvement and no other LNs involved. CONCLUSIONS: Ethically, according to the international recommendations and looking to the statistics of the Sultanate all clinical NO should have the choise of SLN biopsy prior to ALND.

Hook wire localization procedure in biopsy and diagnosis of early breast cancers: Oman experience.

INTRODUCTION: Between January 2000 and December 2005, a total of 30 cases of impalpable suspicious breast lesions (microcalcifications or impalpable lumps classified as BRADS IV and above) were biopsied after hook wire localization. This is a retrospective review of these cases. RESULTS: One third of the suspicious lesions were malignant or pre-malignant. All these had further oncological treatment and follow up. CONCLUSIONS: Hook wire localization biopsy remains an important tool for the diagnosis of impalpable lesions of the breast. The incidence of malignancy in our series was similar to the published international levels. Our series is small, so there is a need to review the data with bigger number.

Meckel Gruber syndrome--a single gene cause of recurrent neural tube defects.

Meckel Gruber syndrome (MGS), an autosomal recessive disorder characterised by posterior encephalocoele, multicystic kidneys and post-axial polydactyly should be recognised by obstetricians and paediatricians to counsel parents regarding the 25% recurrence risk. We report a consanguineous family with MGS affecting three infants.

Which patients with hepatitis C develop liver complications?

To identify variables that are independent predictors of adverse outcomes in chronic hepatitis C, we analyzed a cohort of 455 patients followed for a median of 4.7 years. Associations were sought between demographic and behavioral factors, hepatitis C virus (HCV) genotype, liver histology and liver tests at entry, and development of liver complications, hepatocellular carcinoma (HCC), hepatic transplantation and liver-related death. Independent predictors were identified by multivariate analysis. The following were associated with a significantly higher rate of liver complications: age; birth in Asia, Europe, Mediterranean region, or Egypt; transmission by blood transfusion or sporadic cases; HCV genotypes 1b and 4 (compared with 1/1a); fibrosis stage 3 or 4 (cirrhosis); serum albumin; bilirubin; prothrombin time; and alpha-fetoprotein. However, the only independent predictors of liver-related complications were sporadic transmission (P <.001), advanced fibrosis (P =.004), and low albumin (P <.001). The corresponding independent risk factors for HCC were male gender (P =. 07), sporadic transmission (P <.001), and albumin (P <.001); bilirubin (P =.02) was an additional predictor of transplantation or liver-related death. It is concluded that only patients with advanced hepatic fibrosis or cirrhosis, are at risk of developing hepatic complications of chronic hepatitis C during 5-year follow-up. Among such patients, abnormalities in serum albumin, bilirubin, or prothrombin time indicate a high probability of complications. Patients without definite risk factors for HCV (sporadic cases) are at higher risk of complications, possibly because of interaction between older age, duration of infection, country of birth, and HCV genotypes 1b and 4.

Role of oxidative stress in hypoxia-reoxygenation injury to cultured rat hepatic sinusoidal endothelial cells.

To characterize the role of oxidative stress in cultured rat sinusoidal endothelial cells, we studied the production of superoxide after reoxygenation, the relationship of reduced glutathione (GSH) levels to cell injury, and the protective efficacy of antioxidants. Hypoxia (pO(2) 1-2 mm Hg) was achieved by culturing cells under 95% N(2)5% CO(2) for 4 hours. Reoxygenation was then reestablished, and viability was determined at 24 hours by trypan blue exclusion; putative protective agents were added at the time of reoxygenation (4 hours). As previously reported, reoxygenation after 4 hours hypoxia accentuated sinusoidal cell death fourfold compared with hypoxic or normoxic controls (P <.0001). Superoxide was not produced on reoxygenation, and superoxide dismutase provided no protection against reoxygenation injury. Cellular levels of GSH fell to 37 +/- 4% of normoxic controls (P <.0001) following reoxygenation. These changes were essentially abrogated by Trolox (Aldrich Chemical Co., Milwaukee, WI) and dimethyl sulfoxide, both of which also completely protected against reoxygenation injury. When cellular GSH levels were lowered by addition of diethylmaleate (which conjugates GSH), this reduced the viability of endothelial cells cultured under normoxic conditions and greatly augmented reoxygenation injury. Conversely, addition of exogenous GSH partially protected endothelial cells against hypoxia-reoxygenation injury. Desferrioxamine also protected against reoxygenation injury, but catalase was only partly protective. It is concluded that sinusoidal endothelial cells undergo significant intracellular oxidative stress following reoxygenation, and their viability is critically dependent on GSH levels. Reactive oxygen species are likely mediators of oxidative stress in hepatic sinusoidal endothelial cells.

RP59500 (Quinupristin/dalfopristin): three case reports of its use in infection due to Enterococcus faecium.

We describe three cases of Enterococcus faecium sepsis arising in immunocompromised patients, severely ill with other conditions, who were treated with the new injectable streptogramin RP59500. There are still few reports of clinical experience with this drug. All had bacteriological resolution, with one patient recovering fully. Although two of the three patients died, this was due to underlying disease in one case and a gram-negative superinfection in another. Quinupristin/dalfopristin therapy was not associated with significant adverse effects in any of the patients.

TB or not TB?

These 3 cases illustrate what we believe to be unusual presentations of tuberculosis. In no case was there conclusive proof of infection with Mycobacterium tuberculosis using histological, microbiological or radiological techniques. All were treated empirically with anti-tuberculous medication, with complete recovery. With the re-emergence of tuberculosis, there may be a rise in such cases, and the importance of their recognition and empirical treatment is discussed.

The central role of sinusoidal endothelial cells in hepatic hypoxia-reoxygenation injury in the rat.

The role of individual cell types in hepatic hypoxia-reoxygenation (reperfusion) injury has not been completely defined. We therefore examined the effects of hypoxia and hypoxia-reoxygenation on the viability of rat hepatocytes, Kupffer cells, and sinusoidal endothelial cells (SECs) in primary culture and whether direct exposure to hypoxia followed by reoxygenation activated Kupffer cells. Cultures of hepatocytes (purity > 99%), Kupffer cells (97%), and endothelial cells (> 93%) were established as single-cell types and as cocultures. Hypoxia was achieved by culturing cells under 95% N2/5% CO2, and cell viability was estimated by lactate dehydrogenase (LDH) leakage and Trypan blue exclusion. Kupffer cells and endothelial cells were more resistant to hypoxia than hepatocytes. Following 4-8 hours of hypoxia, reoxygenation accentuated cell death in endothelial cells. In contrast, reoxygenation did not accentuate cell death in hepatocytes or in resting Kupffer cells. The activation of Kupffer cells by the addition of lipopolysaccharide failed to alter their response to hypoxia-reoxygenation. The addition of phorbol myristate acetate to Kupffer cells stimulated the production of superoxide as expected, and the medium from these activated cells augmented the cellular injury of hypoxic hepatocytes. In contrast, hypoxia-reoxygenation did not stimulate Kupffer cells to produce superoxide or other hepatotoxic products. Moreover, Kupffer cells in coculture with hepatocytes did not augment hepatocyte injury after hypoxia-reoxygenation. Likewise, in cocultures of Kupffer cells and SECs, the presence of the Kupffer cell failed to enhance endothelial injury following hypoxia-reoxygenation, and these cocultures did not produce superoxide after reoxygenation. Thus, despite other evidence that Kupffer cells are activated in the intact liver during reperfusion injury, when present in isolation, only endothelial cells possess the innate capacity to undergo hypoxia-reoxygenation injury. Furthermore, changes in oxygen tension alone are not sufficient to activate Kupffer cells to secrete superoxides or other cell products that are toxic to hepatocytes or endothelial cells. It is concluded that SECs play a central role in hypoxia-reoxygenation injury, and the factors that activate Kupffer cells in vivo require further study.