Rhodium catalysed conversion of carbenes into ketenes and ketene imines using PNN pincer complexes

PNN pincer-type rhodium complexes catalyze ketene and ketene imine synthesis, using CO or an isocyanide and a carbene precursor.

Classical Swine Fever in Wild Hog: Report of its Prevalence in Northeast India

Classical swine fever virus (CSFV) is the causative agent of a highly contagious disease, hog cholera in pigs. The disease is endemic in many parts of the world and vaccination is the only way to protect the animals from CSFV infection. Wild hogs belong to the species Sus Scrofa Cristatus under the family Suidae are quite susceptible to CSFV infection. The epidemiological role concerning classical swine fever (CSF) in India is largely unknown. We report here the three isolated cases of CSF in wild hogs from three National parks, namely Kaziranga National Park, Manas National Park and Jaldapara National Park, from north-east part of India. The post-mortem and histopathological findings were clearly indicative for CSFV infection. The presence of CSFV genome was demonstrated in several organs and tissues collected from hogs died due to viral infection. In addition, CSF-specific antibodies were detected in two wild hogs as well as in eighteen feral pigs from the same locations. The phylogenetic analysis of the partial E2 protein gene and 5' untranslated region of CSFV isolates from the wild hog showed identities with genotype 2.2 of the Indian isolates. Occurrence of CSF in wild hogs may pose a potent threat in the epidemiology of the virus in Northeast part of India. To the best of our knowledge, the report presented in the manuscript is the first comprehensive report on CSF in wild hogs form Northeast India. The findings reported would help us to understand the epidemiology and biology of CSFV in wild animals.

The use of a prospective audit proforma to improve door-to-mask times for acute exacerbations chronic obstructive pulmonary disease (COPD) requiring non-invasive ventilation (NIV)

Non-invasive ventilation (NIV) is an evidence based management of acidotic, hypercapnic exacerbations of COPD. Previous national and international audits of clinical practice have shown variation against guideline standards with significant delays in initiating NIV. We aimed to map the clinical pathway to better understand delays and reduce the door-to-NIV time to less than 3 hours for all patients with acidotic, hypercapnic exacerbations of COPD requiring this intervention, by mandating the use of a guideline based educational management proforma.The proforma was introduced at 7 acute hospitals in North London and Essex and initiated at admission of the patient. It was used to record the clinical pathway and patient outcomes until the point of discharge or death. Data for 138 patients were collected. 48% of patients commenced NIV within 3 hours with no reduction in door-to-mask time during the study period. Delays in starting NIV were due to: time taken for review by the medical team (101 minutes) and time taken for NIV to be started once a decision had been made (49 minutes). There were significant differences in door-to-NIV decision and mask times between differing respiratory on-call systems, p < 0.05). The introduction of the proforma had no effect on door-to-mask times over the study period. Main reasons for delay were related to timely access to medical staff and to NIV equipment; however, a marked variation in practice within these hospitals was been noted, with a 9-5 respiratory on-call system associated with shorter NIV initiation times.

Access to diphtheria antitoxin for therapy and diagnostics

The most effective treatment for diphtheria is swift administration of diphtheria antitoxin (DAT) with conjunct antibiotic therapy. DAT is an equine immunoglobulin preparation and listed among the World Health Organization Essential Medicines. Essential Medicines should be available in functioning health systems at all times in adequate amounts, in appropriate dosage forms, with assured quality, and at prices individuals and the community can afford. However, DAT is in scarce supply and frequently unavailable to patients because of discontinued production in several countries, low economic viability, and high regulatory requirements for the safe manufacture of blood-derived products. DAT is also a cornerstone of diphtheria diagnostics but several diagnostic reference laboratories across the European Union (EU) and elsewhere routinely face problems in sourcing DAT for toxigenicity testing. Overall, global access to DAT for both therapeutic and diagnostic applications seems inadequate. Therefore--besides efforts to improve the current supply of DAT--accelerated research and development of alternatives including monoclonal antibodies for therapy and molecular-based methods for diagnostics are required. Given the rarity of the disease, it would be useful to organise a small stockpile centrally for all EU countries and to maintain an inventory of DAT availability within and between countries.

An ultra-broadband low-frequency magnetic resonance system

MR probes commonly employ resonant circuits for efficient RF transmission and low-noise reception. These circuits are narrow-band analog devices that are inflexible for broadband and multi-frequency operation at low Larmor frequencies. We have addressed this issue by developing an ultra-broadband MR probe that operates in the 0.1-3MHz frequency range without using conventional resonant circuits for either transmission or reception. This "non-resonant" approach significantly simplifies the probe circuit and allows robust operation without probe tuning while retaining efficient power transmission and low-noise reception. We also demonstrate the utility of the technique through a variety of NMR and NQR experiments in this frequency range.

Drying, burning and emission characteristics of beehive charcoal briquettes: an alternative household fuel of Eastern Himalayan Region

Beehive charcoal briquettes were produced from powdered charcoal in which soil was added as binder. It was found to be an eco-friendly, clean and economic alternative source of household fuel for the people of Eastern Himalayan Region. Experiments were conducted to determine natural drying behaviour, normalised burn rate, temperature profile and emission of CO, CO2, UBHC (unburnt hydrocarbons) and NO(x) of beehive briquettes prepared from 60:40; 50:50 and 40:60 ratios of charcoal and soil. It was observed that under natural drying conditions (temperature, humidity) briquettes took 433 hr to reach equilibrium moisture content of 5.56-10.29%. Page's model was found suitable to describe the drying characteristics of all three combinations. Normalised burn rate varied between 0.377-0.706% of initial mass min⁻¹. Total burning time of briquette ranged between 133-143 min. The peak temperature attained by briquettes ranged from 437 °C to 572 °C. All the briquette combinations were found suitable for cooking and space heating. Emission of CO, CO2, UBHC, NO and NO2 ranged between 68.4-107.2, 922-1359, 20.9-50.8, 0.19-0.29 and 0.34-0.64 g kg⁻¹, respectively which were less than firewood.

A cohort study to identify simple clinical tests for chronic respiratory failure in obese patients with sleep-disordered breathing

BACKGROUND

Chronic respiratory failure complicating sleep-disordered breathing in obese patients has important adverse clinical implications in terms of morbidity, mortality and healthcare utilisation. Screening strategies are essential to identify obese patients with chronic respiratory failure.

METHOD

Prospective data were collected from patients with obesity-related sleep-disordered breathing admitted for respiratory assessment at a UK national sleep and ventilation centre. Hypercapnia was defined as an arterial partial pressure of carbon dioxide of >6kPa.

RESULTS

245 obese patients (56±13 years) with a body mass index of 48±12 kg/m(2), forced vital capacity (FVC) of 2.1±1.1 L, daytime oximetry (SpO2) of 91±6% and abnormal overnight oximetry were included in the analysis. Receiver operator curve analysis for the whole group showed that an FVC ≤3 L had a sensitivity of 90% and a specificity of 41% in predicting hypercapnia, and an SpO2 ≤95% had a sensitivity of 83% and a specificity of 63% in predicting hypercapnia. Gender differences were observed and receiver operator curve analysis demonstrated 'cut-offs' for (1) SpO2 of ≤95% for men and ≤93% for women and (2) FVC of ≤3.5 L for men and ≤2.3 L for women, in predicting hypercapnia.

CONCLUSIONS

The measurement of FVC and clinic SpO2 in obese patients with abnormal overnight limited respiratory studies predicted hypercapnia. This may have clinical utility in stratifying patients attending sleep clinics.

Two-dimensional NQR using ultra-broadband electronics

We have recently developed an ultra-broadband instrument that can effectively excite and detect NMR and NQR signals over a wide frequency range. Our current system operates between 100 kHz and 3.2 MHz using an un-tuned sample coil. The major benefits of this instrument compared to conventional NQR/NMR systems include increased robustness, ease of use (in particular for multi-frequency experiments), and elimination of the need for tuning adjustments in the hardware. Here we describe its use for performing two-dimensional (2D) scans, which allow improved interpretation of complex NQR spectra by detecting the connected resonances. Our method relies on population transfers between the three energy levels of spin-1 nuclei (such as (14)N) by using multi-frequency excitation and a single RF coil. Experimental results on pure samples and mixtures are also presented.

-174G/C polymorphism in the interleukin-6 promoter is differently associated with prostate cancer incidence depending on race

Interleukin-6 (IL-6), a pro-inflammatory cytokine, is involved in prostate cancer progression, including androgen independence. Serum IL-6 levels also correlate with prostate tumor burden, prostate-specific antigen levels and metastasis. Since circulating cytokine levels vary considerably inter-individually, such variation could be linked to genetic factors, including genetic polymorphism. The -174G>C/rs1800795 polymorphism in the IL-6 promoter is functionally relevant in terms of transcriptional regulation and disease association. We investigated a possible association of the -174G/C polymorphism with prostate cancer. Since significant racial disparities exist in prostate cancer incidence, we also investigated this association between the -174G/C polymorphism and prostate cancer in Caucasians and African-Americans, separately. Direct sequencing of the PCR amplicon from genomic DNA was used for genotyping rs1800795 in all subjects [age-matched controls (N = 140) and prostate cancer patients (N = 164)]. Sample size and power was calculated using the PGA software. We found the GG genotype to be associated with increased risk of prostate cancer in Caucasian subjects, whereas the CC genotype was associated with increased risk in the African-American sample set. Such a dimorphic genotypic association with cancer and race is unique and suggests a complex gene-gene and gene-environment interaction.

Tri-isopropylsilyl thioglycosides as masked glycosyl thiol nucleophiles for the synthesis of S-linked glycosides and glyco-conjugates

Tri-isopropylsilyl thio-glycosides (TIPS S-glycosides), readily synthesized from glycosyl halides, glycosyl acetates, or p-methoxyphenyl glycosides, were in one-pot de-silylated and S-alkylated, -acylated, or -glycosylated in high yields and short time.

Immunodiagnosis as an aid for early detection of Fasciola gigantica by glutathione S-transferase (GST)

In the present study, effort to isolate purified GST from Fasciola gigantica homogenate and its early detection for confirmation of infection has been successful. In this study, immunoprotection studies with GST and antibody titer post-infection has revealed GST to be an immunogenic protein with high sensitivity to detect anti-Fasciola antibody as early as two weeks post-infection in large ruminants.

Summary of the British Thoracic Society guideline for diagnostic flexible bronchoscopy in adults

Flexible bronchoscopy is an essential, established and expanding tool in respiratory medicine. Its practice, however, needs to be safe, effective and for the right indications to maximise clinical utility. This guideline is based on the best available evidence and is a revised update of the British Thoracic Society guideline on diagnostic flexible bronchoscopy.

A new approach of denoising the regular and chaotic signals using Empirical Mode Decomposition: comparison and application

The Empirical Mode Decomposition has been used to present a new approach for denoising of regular and chaotic time series originating from the nonlinear systems. The proposed filtering approach is based on the frequency distribution of different Intrinsic Mode Functions (IMFs). It provides complete frequency and noise strength information present in the data set. The actual frequencies in an experimental data set are distributed among different IMFs which are subsequently disentangled through the algorithm resulting into filtered as well as noise components. The filtered signal is produced only after a suppression (hard threshold) of noise components. The noise strength present in the data set is produced by the identified noisy IMFs. This innovative approach has been tested for linear, nonlinear, and chaotic types of calculated data sets with various levels of simulated noise strengths and results have been compared with the existing methods. The validity of the present approach is confirmed by experimentally observed astrophysical data as well as data from a neutron detector. A sharp improvement in the signal strength has been observed with the proposed method in comparison to the existing methods.

Role of NF-κB as a Prognostic Marker in Breast Cancer : A Pilot Study in Indian Patients

The nuclear factor κB (NF-κB) is a superfamily of transcription factors. It plays an important role in development & progression of cancer. This study was conducted in a tertiary care centre to investigate the significance of NF-κB as a prognostic marker in breast cancer and study its relation with established prognostic markers such as tumor grade, lymph node status, hormone receptor & HER-2/neu expression. We measured NF-κB expression of breast cancer tissue as a test sample & from fibroadenoma as a control. Measurement was done by Western Blot Technique using p65 protein of NF-κB super family of transcription factors. ER,PR and HER-2/neu were measured by immunohistochemistry methods. NF-κB/p65 is significantly associated with large tumor size (≥5 cm), high grade tumors, negative ER, negative PR, positive HER-2/neu and high NPI (≥5.4) scores. NF-κB/p65 expression implies aggressive biological behaviour of breast cancer & this study validates significant association of NF-κB /p65 overexpression with large tumor size, negative estrogen & progesterone receptor status and overexpression of c-erbB2 oncoprotein.

Provision of home mechanical ventilation and sleep services for England survey

The Department of Health is promoting the generation of specialist networks to manage long term ventilatory weaning and domiciliary non-invasive ventilation patients. Currently the availability of these services in England is not known. We performed a short survey to establish the prevalence of sleep and ventilation diagnostic and treatment services. The survey focussed on diagnostic services and Home Mechanical Ventilation (HMV) provision, and was divided into (a) availability of diagnostics, (b) funding, and (c) patient groups. This survey has confirmed that the majority of Home Mechanical Ventilation set-ups are currently for Obesity Related Respiratory Failure and Chronic Obstructive Pulmonary Disease. We have found that there is variable provision of diagnostic services, with the majority of units offering overnight oximetry (95%) but only 55% of responders providing a home mechanical ventilation service. Even more interestingly, less than two thirds of units charged their primary care trust for this service. These data may assist in the development of regional networks and specialist home mechanical ventilation centres.

Detection of constitutive and inducible clindamycin resistance of staphlococcus in a rural tertiary care hospital

Clindamycin has gained immense importance in the treatment of Staphylococcal infections following resistance to Beta-lactam antibiotics, especially after emergence of Methicillin Resistant Staphylococcus aureus. Clindamycin is a valuable treatment option for Staphylococcal isolates that are erythromycin resistant and clindamycin sensitive. However following exposure to erythromycin, clindamycin sensitive strains may lead to constitutive clindamycin resistance and treatment failure. But labeling all erythromycin resistant Staphylococci as clindamycin resistant strain prevents its use in infections caused by true clindamycin sensitive strains. This study aims to detect the presence of inducible clindamycin resistance among clinical isolates of Staphylococci. The detection of inducible clindamycin resistance was performed by D-Test as per the NCCLS guidelines. Among two hundred clinical isolates of Staphylococci studied, there was 24% inducible Clindamycin resistance among all the Staphylococci isolates: 29.4% among Methicillin Resistant Staphylococcus aureus and 21% among Methicillin Sensitive Staphylococcus aureus. It is advisable to include inducible clindamycin resistance testing as part of routine antimicrobial susceptibility testing.

Direct observation of long-lived isomers in 212Bi

Long-lived isomers in (212)Bi have been studied following (238)U projectile fragmentation at 670 MeV per nucleon. The fragmentation products were injected as highly charged ions into a storage ring, giving access to masses and half-lives. While the excitation energy of the first isomer of (212)Bi was confirmed, the second isomer was observed at 1478(30) keV, in contrast to the previously accepted value of >1910 keV. It was also found to have an extended Lorentz-corrected in-ring half-life >30 min, compared to 7.0(3) min for the neutral atom. Both the energy and half-life differences can be understood as being due a substantial, though previously unrecognized, internal decay branch for neutral atoms. Earlier shell-model calculations are now found to give good agreement with the isomer excitation energy. Furthermore, these and new calculations predict the existence of states at slightly higher energy that could facilitate isomer deexcitation studies.

New isomers in the full seniority scheme of neutron-rich lead isotopes: the role of effective three-body forces

The neutron-rich lead isotopes, up to (216)Pb, have been studied for the first time, exploiting the fragmentation of a primary uranium beam at the FRS-RISING setup at GSI. The observed isomeric states exhibit electromagnetic transition strengths which deviate from state-of-the-art shell-model calculations. It is shown that their complete description demands the introduction of effective three-body interactions and two-body transition operators in the conventional neutron valence space beyond (208)Pb.

Copper induced oxidative stress in tea (Camellia sinensis) leaves

Tea [Camellia sinensis L. (O.) Kuntze] is an economically important plantation crop of India but is prone to attack by several fungal pathogens. Copper based fungicides are being used for decades to control fungal diseases in tea which may lead to accumulation of copper in the soil. The biochemical responses to increasing concentrations of copper (50 to 700 microM) were investigated in the leaves of two cultivars of tea commonly grown in the Darjeeling hills. Exposure to excess Cu resulted in increased lipid peroxidation (level of TBARS increased from 3.5 micromol g(-1) f.wt. in control to 12 micromol g(-1) f.wt. in TS-520 plants exposed to 700 mM of Cu), reduced chlorophyll content (from 83.7 microg g(-1) f.wt. in control to 22.5 microg g(-1) f.wt. in TS-520 plants exposed to 700 mM of Cu), higher levels of phenolic compounds(total phenol content increased from 4.54 mg g(-1) f.wt. in control to 5.79 mg g(-1) f.wt. in TS-520 plants exposed to 400 mM of Cu) and an increase in peroxidase enzyme levels. Two new peroxidase isozymes (POD1 and POD2) were detected in plants exposed to Cu. In addition, biochemical responses in two tested cultivars, TS-462 and TS-520 differed significantly. TS-520 was found to be more sensitive to increasing concentrations of Cu. Superoxide dismutase activity increased progressively from 2.55 U mg(-1) protein in control to 5.59 U mg(-1) protein in TS-462 but declined from 4.75 U mg(-1) protein in control to 3.33 U mg(-1) protein in TS-520 when exposed to Cu concentrations higher than 400 microM. Asharp increase in the activity of ascorbate peroxidase (from 0.53 units in control to 2.37 units in plants exposed to 400 mM of Cu) was noticed at the 10th day of exposure in the more tolerant cultivar. On the other hand, catalase levels increased only marginally (from 8.4 to 10.1 units in TS 520 and 8.7 to 10.9 units in TS 462) in both the cultivars. From this study, it appears that Cu exposure led to the production of reactive oxygen species in the leaves resulting in significant lipid peroxidation. Tea plants try to mitigate this oxidative damage through accumulation of phenolic compounds and induction of antioxidant enzymes.

Primary squamous cell carcinoma of kidney - a case report of unusual local recurrence with literature review

Primary squamous cell carcinoma of the kidney is a rare clinical entity. Primary squamous cell carcinoma is more frequently reported in urinary bladder and male urethra than in kidney. Primary renal squamous cell carcinoma (RSCC) accounts for less than 5% of urothelial tumours in urinary system. Very few cases of primary squamous cell carcinoma of kidney have been reported in the world literature. Only forty-six cases over forty four years had been reported from Mayo Clinic. These neoplasms are highly aggressive and locally advanced or metastatic at the time of presentation. Here we report such a case of primary squamous cell  carcinoma of kidney in a 50-year-old lady at a locally recurrent stage with fistulous tract formation.  Palliative radiotherapy came out to be a good clinical modality even in locally recurrent stage in this patient. DOI: http://dx.doi.org/10.3329/bjms.v11i3.11734 Bangladesh Journal of Medical Science Vol. 11 No. 03 July’12

Radiotracers for SPECT imaging: current scenario and future prospects

Single photon emission computed tomography (SPECT) has been the cornerstone of nuclear medicine and today it is widely used to detect molecular changes in cardiovascular, neurological and oncological diseases. While SPECT has been available since the 1980s, advances in instrumentation hardware, software and the availability of new radiotracers that are creating a revival in SPECT imaging are reviewed in this paper.

The biggest change in the last decade has been the fusion of CT with SPECT, which has improved attenuation correction and image quality. Advances in collimator design, replacement of sodium iodide crystals in the detectors with cadmium zinc telluride (CZT) detectors as well as advances in software and reconstruction algorithms have all helped to retain SPECT as a much needed and used technology.

Today, a wide spectrum of radiotracers is available for use in cardiovascular, neurology and oncology applications. The development of several radiotracers for neurological disorders is briefly described in this review, including [123I]FP-CIT (DaTSCANTM) available for Parkinson's disease. In cardiology, while technetium-99m labeled tetrofosmin and technetium-99m labeled sestamibi have been well known for myocardial perfusion imaging, we describe a recently completed multicenter clinical study on the use of [123I]mIBG (AdreViewTM) for imaging in chronic heart failure patients. For oncology, while bone scanning has been prevalent, newer radiotracers that target cancer mechanisms are being developed. Technetium-99m labeled RGD peptides have been reported in the literature that can be used for imaging angiogenesis, while technetium-99m labeled duramycin has been used to image apoptosis.

While PET/CT is considered to be the more advanced technology particularly for oncology applications, SPECT continues to be the modality of choice and the workhorse in many hospitals and nuclear medicine centers. The cost of SPECT instruments also makes them more attractive in developing countries where the cost of a scan is still prohibitive for many patients.

Optical and bio-sensing characteristics of ZnO nanotubes grown by hydrothermal method

ZnO nanostructures were fabricated on copper substrates by hydrothermal method at an optimized growth temperature of -95 degrees C. Structural properties were investigated by field emission scanning electron and transmission electron microscopy. Distinct morphologies were found to be formed at different growth times. The formation of nanotubes mainly involved the initial nucleation followed by the growth of nanorods at 95 degrees C, and then with the increase of dissolution time at room temperature, the preferential chemical dissolution of the metastable Zn-rich [0001] polar surfaces resulted in removing the atoms from the surfaces, thus leading to the thinning of the wall of the nanostructures. Completely hollow ZnO nanotubes could be obtained at a high dissolution time. The room temperature photoluminescence and optical absorption properties of ZnO nanotubes have been studied as a function of dissolution time. The efficacy of ZnO nanotubes for glucose sensing applications has been studied.

Summary of the British Thoracic Society guidelines for advanced diagnostic and therapeutic flexible bronchoscopy in adults

This new guideline covers the rapidly advancing field of interventional bronchoscopy using flexible bronchoscopy. It includes the use of more complex diagnostic procedures such as endobronchial ultrasound, interventions for the relief of central airway obstruction due to malignancy and the recent development of endobronchial therapies for chronic obstructive pulmonary disease and asthma. The guideline aims to help all those who undertake flexible bronchoscopy to understand more about this important area. It also aims to inform respiratory physicians and other specialists dealing with lung cancer of the procedures possible in the management and palliation of central airway obstruction. The guideline covers transbronchial needle aspiration and endobronchial ultrasound-guided transbronchial needle aspiration, electrocautery/diathermy, argon plasma coagulation and thermal laser, cryotherapy, cryoextraction, photodynamic therapy, brachytherapy, tracheobronchial stenting, electromagnetic navigation bronchoscopy, endobronchial valves for emphysema and bronchial thermoplasty for asthma.