Bringing the hospital to the patient: first treatment of stroke patients at the emergency site

Background

Early treatment with rt-PA is critical for favorable outcome of acute stroke. However, only a very small proportion of stroke patients receive this treatment, as most arrive at hospital too late to be eligible for rt-PA therapy.

Methods and Findings

We developed a “Mobile Stroke Unit”, consisting of an ambulance equipped with computed tomography, a point-of-care laboratory system for complete stroke laboratory work-up, and telemedicine capabilities for contact with hospital experts, to achieve delivery of etiology-specific and guideline-adherent stroke treatment at the site of the emergency, well before arrival at the hospital. In a departure from current practice, stroke patients could be differentially treated according to their ischemic or hemorrhagic etiology even in the prehospital phase of stroke management. Immediate diagnosis of cerebral ischemia and exclusion of thrombolysis contraindications enabled us to perform prehospital rt-PA thrombolysis as bridging to later intra-arterial recanalization in one patient. In a complementary patient with cerebral hemorrhage, prehospital diagnosis allowed immediate initiation of hemorrhage-specific blood pressure management and telemedicine consultation regarding surgery. Call-to-therapy-decision times were 35 minutes.

Conclusion

This preliminary study proves the feasibility of guideline-adherent, etiology-specific and causal treatment of acute stroke directly at the emergency site.     

A molecular phylogeny of ichthyophiid caecilians (Amphibia: Gymnophiona: Ichthyophiidae): out of India or out of South East Asia?

Recent molecular phylogenetic studies indicate that the rafting Indian plate harboured several isolated vertebrate lineages between ca. 130 and 56 Myr ago that dispersed and diversified 'out of India' following accretion with Eurasia. A single family of the amphibian order Gymnophiona, the Ichthyophiidae, presently occurs on the Indian plate and across much of South East Asia. Ichthyophiid phylogeny is investigated in order to test competing out of India and out of South East Asia hypotheses for their distribution. Partial sequences of mitochondrial 12S and 16S rRNA and cytochrome b genes for 20 ichthyophiids and proximate outgroups were assembled. Parsimony, maximum-likelihood and distance analyses all recover optimum trees in which uraeotyphlids plus Ichthyophis cf. malabarensis are the sister taxa to all other Ichthyophis, among which the South East Asian taxa are monophyletic. Tree topology and branch lengths indicate that the Indian lineages are more basal and older, and thus are more consistent with the hypothesis that ichthyophiids dispersed from the Indian subcontinent into South East Asia. The estimated relationships also support monophyly of Sri Lankan Ichthyophis, and non-monophyly of striped and unstriped Ichthyophis species groups. Mitochondrial DNA sequences provide evidence that should assist current problematic areas of caecilian taxonomy.     

Therapeutic Non-Toxic Doses of TNF Induce Significant Regression in TNFR2-p75 Knockdown Lewis Lung Carcinoma Tumor Implants

Tumor necrosis factor-alpha (TNF) binds to two receptors: TNFR1/p55-cytotoxic and TNFR2/p75-pro-survival. We have shown that tumor growth in p75 knockout (KO) mice was decreased more than 2-fold in Lewis lung carcinoma (LLCs). We hypothesized that selective blocking of TNFR2/p75 LLCs may sensitize them to TNF-induced apoptosis and affect the tumor growth. We implanted intact and p75 knockdown (KD)-LLCs (>90%, using shRNA) into wild type (WT) mice flanks. On day 8 post-inoculation, recombinant murine (rm) TNF-α (12.5 ng/gr of body weight) or saline was injected twice daily for 6 days. Tumor volumes (tV) were measured daily and tumor weights (tW) on day 15, when study was terminated due to large tumors in LLC+TNF group. Tubular bones, spleens and peripheral blood (PB) were examined to determine possible TNF toxicity. There was no significant difference in tV or tW between LLC minus (-) TNF and p75KD/LLC-TNF tumors. Compared to 3 control groups, p75KD/LLC+TNF showed >2-5-fold decreases in tV (p<0.001) and tW (p<0.0001). There was no difference in tV or tW end of study vs. before injections in p75KD/LLC+TNF group. In 3 other groups tV and tW were increased 2.7-4.5-fold (p<0.01, p<0.0002 and p<0.0001). Pathological examination revealed that 1/3 of p75KD/LLC+rmTNF tumors were 100% necrotic, the remaining revealed 40-60% necrosis. No toxicity was detected in bone marrow, spleen and peripheral blood. We concluded that blocking TNFR2/p75 in LLCs combined with intra-tumoral rmTNF injections inhibit LLC tumor growth. This could represent a novel and effective therapy against lung neoplasms and a new paradigm in cancer therapeutics.     

Synthesis,DNA Binding,and Oxidative Cleavage Studies of Fe(II) and Co(III) Complexes Containing Bioactive Ligands

The two complexes containing bioactive ligands of the type and [Fe(L)] (PF₆)₂ (1) (where L = [1-{[2-{[2-hydroxynaphthalen-1-yl)methylidine]amino}phenyl)imino] methyl}naphthalene-2-ol]) and [Co(L₁L₂)] (PF₆)₃ (2) (where L₁L₂ = mixed ligand of 2-seleno-4-methylquinoline and 1,10-phenanthroline in the ratio 1:2, respectively) were synthesized and structurally characterized. The DNA binding property of the complexes with calf thymus DNA has been investigated using absorption spectra, viscosity measurements, and thermal denaturation experiments. Intrinsic binding constant K_b has been estimated at room temperature. The absorption spectral studies indicate that the complexes intercalate between the base pairs of the CT-DNA tightly with intrinsic DNA binding constant of 2.8 × 10⁵ M^?1 for (1) and 4.8 × 10⁵ M^?1 for (2) in 5 mM Tris-HCl/50 mM NaCl buffer at pH 7.2, respectively. The oxidative cleavage activity of (1) and (2) were studied by using gel electrophoresis and the results show that complexes have potent nuclease activity.     

Tuberculosis contact screening and isoniazid preventive therapy in a South Indian district: operational issues for programmatic consideration

Background

Under India''s Revised National Tuberculosis Control Programme (RNTCP), all household contacts of sputum smear positive Pulmonary Tuberculosis (PTB) patients are screened for TB. In the absence of active TB disease, household contacts aged <6 years are eligible for Isoniazid Preventive Therapy (IPT) (5 milligrams/kilogram body weight/day) for 6 months.

Objectives

To estimate the number of household contacts aged <6 years, of sputum smear positive PTB patients registered for treatment under RNTCP from April to June''2008 in Krishna District, to assess the extent to which they are screened for TB disease and in its absence initiated on IPT.

Methods

A cross sectional study was conducted. Households of all smear positive PTB cases (n = 848) registered for treatment from April to June''2008 were included. Data on the number of household contacts aged <6 years, the extent to which they were screened for TB disease, and the status of initiation of IPT, was collected.

Results

Households of 825 (97%) patients were visited, and 172 household contacts aged <6 years were identified. Of them, 116 (67%) were evaluated for TB disease; none were found to be TB diseased and 97 (84%) contacts were initiated on IPT and 19 (16%) contacts were not initiated on IPT due to shortage of INH tablets in peripheral health centers. The reasons for non-evaluation of the remaining eligible children (n = 56, 33%) include no home visit by the health staff in 25 contacts, home visit done but not evaluated in 31 contacts. House-hold contacts in rural areas were less likely to be evaluated and initiated on IPT [risk ratio 6.65 (95% CI; 3.06–14.42)].

Conclusion

Contact screening and IPT implementation under routine programmatic conditions is sub-optimal. There is an urgent need to sensitize all concerned programme staff on its importance and establishment of mechanisms for rigorous monitoring.     

Genetic Structure of Tibeto-Burman Populations of Bangladesh: Evaluating the Gene Flow along the Sides of Bay-of-Bengal

Human settlement and migrations along sides of Bay-of-Bengal have played a vital role in shaping the genetic landscape of Bangladesh, Eastern India and Southeast Asia. Bangladesh and Northeast India form the vital land bridge between the South and Southeast Asia. To reconstruct the population history of this region and to see whether this diverse region geographically acted as a corridor or barrier for human interaction between South Asia and Southeast Asia, we, for the first time analyzed high resolution uniparental (mtDNA and Y chromosome) and biparental autosomal genetic markers among aboriginal Bangladesh tribes currently speaking Tibeto-Burman language. All the three studied populations; Chakma, Marma and Tripura from Bangladesh showed strikingly high homogeneity among themselves and strong affinities to Northeast Indian Tibeto-Burman groups. However, they show substantially higher molecular diversity than Northeast Indian populations. Unlike Austroasiatic (Munda) speakers of India, we observed equal role of both males and females in shaping the Tibeto-Burman expansion in Southern Asia. Moreover, it is noteworthy that in admixture proportion, TB populations of Bangladesh carry substantially higher mainland Indian ancestry component than Northeast Indian Tibeto-Burmans. Largely similar expansion ages of two major paternal haplogroups (O2a and O3a3c), suggested that they arose before the differentiation of any language group and approximately at the same time. Contrary to the scenario proposed for colonization of Northeast India as male founder effect that occurred within the past 4,000 years, we suggest a significantly deep colonization of this region. Overall, our extensive analysis revealed that the population history of South Asian Tibeto-Burman speakers is more complex than it was suggested before.     

Sphingosine,a Modulator of Human Translesion DNA Polymerase Activity

Translesion (TLS) DNA polymerases are specialized, error-prone enzymes that synthesize DNA across bulky, replication-stalling DNA adducts. In so doing, they facilitate the progression of DNA synthesis and promote cell proliferation. To potentiate the effect of cancer chemotherapeutic regimens, we sought to identify inhibitors of TLS DNA polymerases. We screened five libraries of ∼3000 small molecules, including one comprising ∼600 nucleoside analogs, for their effect on primer extension activity of DNA polymerase η (Pol η). We serendipitously identified sphingosine, a lipid-signaling molecule that robustly stimulates the activity of Pol η by ∼100-fold at low micromolar concentrations but inhibits it at higher concentrations. This effect is specific to the Y-family DNA polymerases, Pols η, κ, and ι. The addition of a single phosphate group on sphingosine completely abrogates this effect. Likewise, the inclusion of other sphingolipids, including ceramide and sphingomyelin to extension reactions does not elicit this response. Sphingosine increases the rate of correct and incorrect nucleotide incorporation while having no effect on polymerase processivity. Endogenous Pol η activity is modulated similarly as the recombinant enzyme. Importantly, sphingosine-treated cells exhibit increased lesion bypass activity, and sphingosine tethered to membrane lipids mimics the effects of free sphingosine. Our studies have uncovered sphingosine as a modulator of TLS DNA polymerase activity; this property of sphingosine may be associated with its known role as a signaling molecule in regulating cell proliferation in response to cellular stress.     

Is One Sputum Specimen as Good as Two during Follow-Up Cultures for Monitoring Multi Drug Resistant Tuberculosis Patients in India?

Background

In India, the Revised National Tuberculosis Control Programme (RNTCP) has adopted the strategy of examining two specimens during follow-up culture examinations to monitor the treatment response of multi-drug resistant tuberculosis (MDR-TB) patients.

Objectives

To determine the incremental yield of the second sputum specimen during follow-up culture examinations among patients with MDR-TB and the effect on case management on changing from two to one specimen follow-up strategy.

Methods

A cross sectional record review of MDR-TB patients registered during 2008–09 under RNTCP was undertaken in three MDR-TB treatment sites of India.

Results

Of 1721 pairs of follow-up sputum culture examinations done among 220 MDR-TB patients, 451(26%) were positive with either of the two specimens; 29(1.7%) were culture positive only on the second specimen indicating the incremental yield. To detect one additional culture positive result on the second specimen, 59 specimens needed to be processed. If we had examined only one specimen, we would have missed 29 culture-positive results. By current RNTCP guidelines, however, a single specimen policy would have altered case management in only 3(0.2%) instances, where patients would have missed a one month extension of the intensive phase of MDR-TB treatment. There is no meaningful advantage in using two specimens for the monitoring of MDR-TB patients. A single specimen policy could be safely implemented with negligible clinical effect on MDR-TB patients and favourable resource implications for RNTCP.     

The Phylogeography of Y-Chromosome Haplogroup H1a1a-M82 Reveals the Likely Indian Origin of the European Romani Populations

Linguistic and genetic studies on Roma populations inhabited in Europe have unequivocally traced these populations to the Indian subcontinent. However, the exact parental population group and time of the out-of-India dispersal have remained disputed. In the absence of archaeological records and with only scanty historical documentation of the Roma, comparative linguistic studies were the first to identify their Indian origin. Recently, molecular studies on the basis of disease-causing mutations and haploid DNA markers (i.e. mtDNA and Y-chromosome) supported the linguistic view. The presence of Indian-specific Y-chromosome haplogroup H1a1a-M82 and mtDNA haplogroups M5a1, M18 and M35b among Roma has corroborated that their South Asian origins and later admixture with Near Eastern and European populations. However, previous studies have left unanswered questions about the exact parental population groups in South Asia. Here we present a detailed phylogeographical study of Y-chromosomal haplogroup H1a1a-M82 in a data set of more than 10,000 global samples to discern a more precise ancestral source of European Romani populations. The phylogeographical patterns and diversity estimates indicate an early origin of this haplogroup in the Indian subcontinent and its further expansion to other regions. Tellingly, the short tandem repeat (STR) based network of H1a1a-M82 lineages displayed the closest connection of Romani haplotypes with the traditional scheduled caste and scheduled tribe population groups of northwestern India.