Metabolism of 2-Chloro-4-Nitrophenol in a Gram Negative Bacterium, Burkholderia sp. RKJ 800

A 2-Chloro-4-nitrophenol (2C4NP) degrading bacterial strain designated as RKJ 800 was isolated from a pesticide contaminated site of India by enrichment method and utilized 2C4NP as sole source of carbon and energy. The stoichiometric amounts of nitrite and chloride ions were detected during the degradation of 2C4NP. On the basis of thin layer chromatography, high performance liquid chromatography and gas chromatography-mass spectrometry, chlorohydroquinone (CHQ) and hydroquinone (HQ) were identified as major metabolites of the degradation pathway of 2C4NP. Manganese dependent HQ dioxygenase activity was observed in the crude extract of 2C4NP induced cells of the strain RKJ 800 that suggested the cleavage of the HQ to γ-hydroxymuconic semialdehyde. On the basis of the 16S rRNA gene sequencing, strain RKJ 800 was identified as a member of genus Burkholderia. Our studies clearly showed that Burkholderia sp. RKJ 800 degraded 2-chloro-4-nitrophenol via hydroquinone pathway. The pathway identified in a gram negative bacterium, Burkholderia sp. strain RKJ 800 was differed from previously reported 2C4NP degradation pathway in another gram-negative Burkholderia sp. SJ98. This is the first report of the formation of CHQ and HQ in the degradation of 2C4NP by any gram-negative bacteria. Laboratory-scale soil microcosm studies showed that strain RKJ 800 is a suitable candidate for bioremediation of 2C4NP contaminated sites

Study - Skin changes in internal malignancy

BACKGROUND: Internal malignancies are accompanied by various skin changes which may be specific infiltrates or non-specific changes. This study is aimed at determining the frequency of such changes in malignant disease treatment center attendees in India. METHODS: A study of 300 confirmed cases of internal malignancy at a malignant disease treatment center was undertaken to evaluate these skin changes. Specific infiltrates were confirmed by histopathology. Statistical methods were employed to calculate significance in non-specific lesions by comparing with 300 controls not suffering from internal malignancy. RESULTS: Skin changes were present in 82 (27.3%). Cutaneous metastases were found in 19 (6.3%); non-contiguous in 5 (1.6%); contiguous in 14 (4.3%). Non-specific skin lesions numbered 74 (11.6%) in 52 patients. Statistically significant non-specific skin changes were acquired ichthyosis, herpes zoster and generalized pruritus. CONCLUSION: Metastases usually occurred late in internal malignancy (17, 5.6%) except in a case each of histiocytic lymphoma and non-Hodgkin's lymphoma (2, 0.7%) where the lesions preceded malignancy by 3 months and 1 month respectively. Contiguous nodules were a marker of relapse after surgery in 3 (1%)

Autistic traits and individual brain differences: functional network efficiency reflects attentional and social impairments, structural nodal efficiencies index systemising and theory-of-mind skills

Background: Autism is characterised not only by impaired social cognitive 'empathising' but also by superior rule-based 'systemising'. These cognitive domains intertwine within the categorical diagnosis of autism, yet behavioural genetics suggest largely independent heritability, and separable brain mechanisms. We sought to determine whether quantitative behavioural measures of autistic traits are dimensionally associated with structural and functional brain network integrity, and whether brain bases of autistic traits vary independently across individuals. Methods: 30 right-handed neurotypical adults (12 females) were administered psychometric (Social Responsiveness Scale, Autism Spectrum Quotient, and Systemising Quotient) and behavioural (Attention Network Test and theory-of-mind reaction time) measures of autistic traits, and structurally (diffusion tensor imaging) and functionally (500 s of 2 Hz eyes-closed resting fMRI) derived graph-theoretic measures of efficiency of information integration were computed throughout the brain and within subregions. Results: Social impairment was positively associated with functional efficiency (r=.47, p=.006), globally and within temporo-parietal and prefrontal cortices. Delayed orienting of attention likewise associated with greater functional efficiency (r=-.46., p=.0133). Systemising was positively associated with global structural efficiency (r=.38, p=0.018), driven specifically by temporal pole; theory-of-mind reaction time was related to structural efficiency (r=-.40, p=0.0153) within right supramarginal gyrus. Limitations: Interpretation of these relationships is complicated by the many senses of the term 'connectivity', including, functional, structural, and computational; by the approximation inherent in group functional anatomical parcellations when confronted with individual variation in functional anatomy; and by the validity, sensitivity and specificity of the several survey and experimental behavioural measures applied as correlates of brain structure and function. Conclusions: Functional connectivities highlight distributed networks associated with domain-general properties such as attentional orienting and social cognition broadly, associating more impaired behaviour with more efficient brain networks that may reflect heightened feedforward information flow subserving autistic strengths and deficits alike. Structural connectivity results highlight specific anatomical nodes of convergence, reflecting cognitive and neuroanatomical independence of systemising and theory-of-mind. In addition, this work shows that individual differences in theory-of-mind related to brain structure can be measured behaviourally, and offers neuroanatomical evidence to pin down the slippery construct of ‘systemising’ as the capacity to construct invariant contextual associations

Private patient perceptions about a public programme; what do private Indian tuberculosis patients really feel about directly observed treatment?

<p>Abstract</p> <p>Background</p> <p>India accounts for one-fifth of the global incident cases of tuberculosis(TB). The country presently has the world's largest directly observed treatment, short course (DOTS) programme, that has shown impressive results and covers almost 100% of the billion-plus Indian population. Despite such a successful programme, the majority of Indian patients with tuberculosis prefer private healthcare, although repeated audits of this sector have shown the quality to be poor.</p> <p>We aimed to ascertain the level of awareness and knowledge of private patients with tuberculosis attending our clinic at a tertiary private healthcare institute with regards to the DOTS programme, understanding the reasons behind their preference for private healthcare, and evaluating their perceptions and reasons for accepting or failing to accept directly observed therapy as a treatment option.</p> <p>Methods</p> <p>A structured interview schedule was administered to private patients with tuberculosis at the P.D. Hinduja Hospital and Medical Research Centre, Mumbai, India between January 2006 to November 2007.</p> <p>Results</p> <p>Only 30 of 200 patients (15%) were aware of the DOTS programme. After being explained what directly observed therapy was, 136 patients (68%) found this form of treatment unacceptable.183 patients (91.5%) preferred buying the drugs themselves to visiting a DOTS centre. 90 patients (45%) were not prepared to be observed while swallowing their TB drugs, finding it an intrusion of privacy.</p> <p>Conclusions</p> <p>Our study reveals a poor knowledge and awareness of the DOTS programme among the cohort of TB patients that we interviewed. The control of TB in India will undoubtedly benefit from more patients being attracted to and treated by the existing DOTS programmes. However, directly observed treatment, in its present form, is considered too rigid and intrusive and is unlikely to be accepted by a majority of patients seeking private healthcare. Novel strategies and more flexible options will have to be devised to ensure higher cure rates without compromising patient choice.</p

Discovering Conformational Sub-States Relevant to Protein Function

Background: Internal motions enable proteins to explore a range of conformations, even in the vicinity of native state. The role of conformational fluctuations in the designated function of a protein is widely debated. Emerging evidence suggests that sub-groups within the range of conformations (or sub-states) contain properties that may be functionally relevant. However, low populations in these sub-states and the transient nature of conformational transitions between these substates present significant challenges for their identification and characterization. Methods and Findings: To overcome these challenges we have developed a new computational technique, quasianharmonic analysis (QAA). QAA utilizes higher-order statistics of protein motions to identify sub-states in the conformational landscape. Further, the focus on anharmonicity allows identification of conformational fluctuations that enable transitions between sub-states. QAA applied to equilibrium simulations of human ubiquitin and T4 lysozyme reveals functionally relevant sub-states and protein motions involved in molecular recognition. In combination with a reaction pathway sampling method, QAA characterizes conformational sub-states associated with cis/trans peptidyl-prolyl isomerization catalyzed by the enzyme cyclophilin A. In these three proteins, QAA allows identification of conformational sub-states, with critical structural and dynamical features relevant to protein function. Conclusions: Overall, QAA provides a novel framework to intuitively understand the biophysical basis of conformational diversity and its relevance to protein function. © 2011 Ramanathan et al

Marked alveolar apoptosis/proliferation imbalance in end-stage emphysema

BACKGROUND: Apoptosis has recently been proposed to contribute to the pathogenesis of emphysema. METHODS: In order to establish if cell fate plays a role even in end-stage disease we studied 16 lungs (9 smoking-associated and 7 α1antitrypsin (AAT)-deficiency emphysema) from patients who had undergone lung transplantations. Six unused donor lungs served as controls. Apoptosis was evaluated by TUNEL analysis, single-stranded DNA laddering, electron microscopy and cell proliferation by an immunohistochemical method (MIB1). The role of the transforming growth factor (TGF)-β1 pathway was also investigated and correlated with epithelial cell turnover and with the severity of inflammatory cell infiltrate. RESULTS: The apoptotic index (AI) was significantly higher in emphysematous lungs compared to the control group (p ≤ 0.01), particularly if only lungs with AAT-deficiency emphysema were considered (p ≤ 0.01 vs p = 0.09). The proliferation index was similar in patients and controls (1.9 ± 2.2 vs 1.7 ± 1.1). An increased number of T lymphocytes was observed in AAT-deficiency lungs than smoking-related cases (p ≤ 0.05). TGF-β1 expression in the alveolar wall was higher in patients with smoking-associated emphysema than in cases with AAT-deficiency emphysema (p ≤ 0.05). A positive correlation between TGF-βRII and AI was observed only in the control group (p ≤ 0.005, r(2 )= 0.8). A negative correlation was found between the TGF-β pathway (particularly TGF-βRII) and T lymphocytes infiltrate in smoking-related cases (p ≤ 0.05, r(2 )= 0.99) CONCLUSION: Our findings suggest that apoptosis of alveolar epithelial cells plays an important role even in end-stage emphysema particularly in AAT-deficiency disease. The TGFβ-1 pathway does not seem to directly influence epithelial turnover in end-stage disease. Inflammatory cytokine different from TGF-β1 may differently orchestrate cell fate in AAT and smoking-related emphysema types