Tubercular dactylitis: Fine needle aspiration cytology as a diagnostic modality

OBJECTIVE: To evaluate the efficacy of aspiration cytology in the early diagnosis of tuberculous dactylitis and describe the spectrum of cytomorphologic features in these cases. STUDY DESIGN: We studied 12 cases of dactylitis diagnosed as of tubercular etiology by fine needle aspiration cytology (FNAC) over a period of 6 years and assessed the clinicoradiologic features. The stained slides were reviewed and the spectrum of features noted. RESULTS: The most common clinical presentation was an indurated swelling of the involved digit (100%). On radiography, most often an expansile, lytic lesion along with soft tissue swelling was noted in 83% of cases. However, the clinical diagnosis did not consider a tubercular (TB) etiology. FNAC of these cases showed variable features; the most common was granulomas with or without necrosis (75% in total). Two cases showed acute suppurative cytology, and 1 revealed only fibroblasts and afew neutrophils. On the basis of suspicion, staining for acid-fast bacilli (AFB) was done in all cases, and bacilli were identified in all of them after a thorough search. These patients were soon started on antituberculous therapy, with significant improvements. CONCLUSION: FNAC can serve as an inexpensive and comparatively less invasive procedure for early diagnosis of TB dactylitis, permitting timely initiation of specific therapy. This study also highlighted the unusual cytomorphology in some cases. Clinicians and pathologists should maintain a high index of suspicion in cases of dactylitis and stain for AFB in all cases.     

Decreased GABA Receptor Binding in the Cerebral Cortex of Insulin Induced Hypoglycemic and Streptozotocin Induced Diabetic Rats

Hypoglycemia is the major problem to blood glucose homeostasis in treatment of diabetes and is associated with severe irreversible consequences including seizures, coma and death. GABAergic inhibitory function in the cerebral cortex plays an important role in controlling the excitability and responsiveness of cortical neurons. Present study analysed effects of insulin induced hypoglycemia and streptozotocin induced diabetes on the cortical GABA receptor binding, GABA_Aά1, GABA_B receptor subtype expression, GAD and GLUT3 expression. Diabetic rats showed decreased [³H] GABA binding in the cerebral cortex compared to control while hypoglycemia exacerbated the decrease. GABA receptor subunits; GABA_Aά1, GABA_B and GAD expression significantly decreased in diabetic rats whereas hypoglycemia significanly decreased the expression compared to diabetic. GLUT3 expression significantly up regulated during both hypo and hyperglycemia. Our results showed that hypoglycemia and hyperglycemia decreased GABAergic neuroprotective function in the cerebral cortex, which account for the increased vulnerability of cerebral cortex to subsequent neuronal damage during hypo/hyperglycemia.     

Alkaline pre-treatment of oilseed rape straw for bioethanol production: evaluation of glucose yield and pre-treatment energy consumption

The objective of the research was to investigate the effect of biomass loading, alkali (NaOH) concentration and pre-treatment time on the yield of glucose obtained following alkaline pre-treatment and enzymatic hydrolysis of oilseed rape (OSR) straw. A maximum glucose yield of (440.6 ± 14.9) g glucose kg⁻¹ biomass was obtained when OSR straw was pre-treated at a biomass loading of 50 g kg⁻¹ and an alkali concentration of 0.63 mol dm⁻³ NaOH for 30 min. The energy efficiency of glucose extraction (0.39 kg glucose MJ⁻¹ consumed) was highest when OSR straw was pre-treated at a biomass loading of 50 g kg⁻¹ and an alkali concentration of 0.63 or 0.75 mol dm⁻³ for 30 min. The study demonstrated alkaline pre-treatment of OSR straw is superior to acid pre-treatment in terms of glucose yield and energy efficiency.     

Signalling in space and time: systems dynamics of intracellular communication

The second edition of the EMBO Spatial meeting took place in May 2011 in Engelberg, Switzerland. Although the work presented at the meeting covered a challengingly broad range of topics, it accomplished the rare goal of promoting interactions between cell biologists, neuroscientists, systems biologists and mathematicians, all united by a common interest in understanding how cells integrate signals in space and time.     

Analyzing media coverage of the global fund diseases compared with lower funded diseases (childhood pneumonia, diarrhea and measles)

Background

Pneumonia, diarrhea and measles are the leading causes of death in children worldwide, but have a disproportionately low share of international funding and media attention [1]–[3]. In comparison, AIDS, tuberculosis and malaria - diseases that also significantly affect children – receive considerably more funding and have relatively high media coverage. This study investigates the potential relationship between media agenda setting and funding levels in the context of the actual burden of disease.

Methods

The news databases Lexis Nexis, Factiva, and Google News Archive were searched for the diseases AIDS, TB and Malaria and for lower funded pediatric diseases: childhood pneumonia, diarrhea, and measles. A sample of news articles across geographic regions was also analyzed using a qualitative narrative frame analysis of how the media stories were told.

Results

There were significantly more articles addressing the Global Fund diseases compared to the lower funded pediatric diseases between 1981 and 2008 (1,344,150 versus 291,865 articles). There were also notable differences in the framing of media narratives: 1) There was a high proportion of articles with the primary purpose of raising awareness for AIDS, TB and malaria (46.2%) compared with only 17.9% of the pediatric disease articles. 2) Nearly two-thirds (61.5%) of the AIDS, tuberculosis and malaria articles used a human rights, legal or social justice frame, compared with 46.2% for the lower funded pediatric disease articles, which primarily used an ethical or moral frame.

Conclusion

This study demonstrates that lower funded pediatric diseases are presented differently in the media, both quantitatively and qualitatively, than higher funded, higher profile diseases.     

Longevity of animals under reactive oxygen species stress and disease susceptibility due to global warming

The world is projected to experience an approximate doubling of atmospheric CO_2 concentration in the next decades. Rise in atmospheric CO_2 level as one of the most important reasons is expected to contribute to raise the mean global temperature 1.4 ℃-5.8 ℃ by that time. A survey from 128 countries speculates that global warming is primarily due to increase in atmospheric CO_2 level that is produced mainly by anthropogenic activities. Exposure of animals to high environmental temperatures is mostly accompanied by unwanted acceleration of certain biochemical pathways in their cells. One of such examples is augmentation in generation of reactive oxygen species(ROS) and subsequent increase in oxidation of lipids, proteins and nucleic acids by ROS. Increase in oxidation of biomolecules leads to a state called as oxidative stress(OS). Finally, the increase in OS condition induces abnormality in physiology of animals under elevated temperature. Exposure of animals to rise in habitat temperature is found to boost the metabolism of animals and a very strong and positive correlation exists between metabolism and levels of ROS and OS. Continuous induction of OS is negatively correlated with survivability and longevity and positively correlated with ageing in animals. Thus, it can be predicted that continuous exposure of animals to acute or gradual rise in habitat temperature due to global warming may induce OS, reduced survivability and longevity in animals in general and poikilotherms in particular. A positive correlation between metabolism and temperature in general and altered O_2 consumption at elevated temperature in particular could also increase the risk of experiencing OS in homeotherms. Effects of global warming on longevity of animals through increased risk of protein misfolding and disease susceptibility due to OS as the cause or effects or both also cannot be ignored. Therefore, understanding the physiological impacts of global warming in relation to longevity of animals will become very crucial challenge to biologists of the present millennium.     

Cytomorphologic spectrum in paraganglioma

OBJECTIVE: To study the detailed cytologic features of paragangliomas (PGs) and delineate features helpful in predicting behavior. STUDY DESIGN: We performed retrospective analysis of 12 cases cytologically suggested as PG over a period of 10 years. Smears were reviewed for cellularity, pattern, shape, cytoplasm, nuclear features and background. Cytologic diagnosis was correlated with clinicoradiologic features, histologic features and immunocytochemistry. RESULTS: Patient age ranged from 12 to 65 years, with male preponderance; they presented with a mass lesion. Sites involved were head and neck (5), retroperitoneum (5) and mediastinum (2). Smears were cellular; cells were round to oval, plasmacytoid and spindled and seen as scattered, in clusters, acinar and perivascular pattern. The most consistent feature was presence of pink granules. Pleomorphism was present in all but 1 case and less prominent in tumors with metastasis. Mitoses were more frequently seen in malignant cases. CONCLUSION: Cytologic features of PG are diverse. Although there are certain main features, they are not diagnostic unless combined with data on site, histology and ancillary studies. Presence of granules, mild pleomorphism, frequent mitoses and necrosis needs careful evaluation for malignancy potential and warrants close follow-up.     

GTP avoidance in Tetrahymena thermophila requires tyrosine kinase activity, intracellular calcium, NOS, and guanylyl cyclase

Guanosine 5'-triphosphate (GTP) is a chemorepellent in Tetrahymena thermophila that has been shown to stimulate cell division as well as ciliary reversal. Previous studies have proposed that GTP avoidance is linked to a receptor-mediated, calcium-based depolarization. However, the intracellular mechanisms involved in GTP avoidance have not been previously documented. In this study, we examine the hypothesis that GTP signals through a tyrosine kinase pathway in T. thermophila. Using behavioral assays, enzyme immunosorbent assays, Western blotting, and immunofluorescence, we present data that implicate a tyrosine kinase, phospholipase C, intracellular calcium, nitric oxide synthase (NOS) and guanylyl cyclase in GTP signaling. The tyrosine kinase inhibitor genistein eliminates GTP avoidance in Tetrahymena in behavioral assays. Similarly, pharmacological inhibitors of phospholipase C, NOS, and guanylyl cyclase all eliminated Tetrahymena avoidance to GTP. Immunofluorescence data shows evidence of tyrosine kinase activity in the cilia, suggesting that this enzyme activity could be directly involved in ciliary reversal.     

Efficiency of Coleus aromaticus extract in modifying cyclophosphamide and mitomycin-C induced clastogenicity in mouse bone marrow cells

The anticlastogenic potency of the ethanolic extract of a medicinal plant, C. aromaticus was investigated by taking bone marrow chromosomal aberration assay and micronucleus (MN) test as the test parameters. Swiss albino mice were fed orally with different doses (10,15, 25, 50 and 100 mg/kg body weight) of ethanolic extract for 7 days and on the 7th day, two doses each of anticancer drugs cyclophosphamide (CP; 25 and 50 mg/kg body weight) and mitomycin-C (MMC; 4 and 8 mg/kg body weight) were injected, ip, to different groups of animals. Bone marrow MN preparations were made at 24 and 48 hr time intervals. Coleus extract reduced CP and MMC induced MN and lower doses of the extract were found to be more effective than higher doses. The effective doses of extract in MN test were selected to study the anticlastogenic effects against CP (25 and 50 mg/kg body weight) and MMC (2 and 4 mg/kg body weight) induced chromosomal aberrations. The results indicate the protective effect of C. aromaticus against CP and MMC induced cytogenetic damage.