Randomised controlled trial evaluating the role of tirofiban in high-risk non-ST elevation acute coronary syndromes: an East Indian perspective

INTRODUCTION

Glycoprotein IIb/IIIa inhibitors such as tirofiban inhibit platelet aggregation. We evaluated the immediate and early outcomes in patients with high-risk non-ST elevation acute coronary syndrome (NSTE ACS) who received tirofiban with conventional therapy compared to patients who received only conventional therapy (a combination of aspirin, clopidogrel, low-molecular-weight heparin with or without beta-blockers and angiotensin-converting enzyme inhibitors).

METHODS

A total of 165 patients received conventional therapy with a placebo, and 136 patients received conventional therapy with tirofiban after randomisation. The outcomes were measured on Day 7, Day 14, one month and three months after the administration of therapy.

RESULTS

A significant reduction was noted in the occurrence of primary endpoints in patients receiving tirofiban, compared to those who received a placebo at seven days (14 versus 32; p-value is 0.036), 14 days (14 versus 28; p-value is 0.043), one month (19 versus 34; p-value is 0.01) and three months (30 versus 44; p-value is less than 0.001) after administration. There was a significant reduction in the occurrence of fatal myocardial infarction (MI) (1 versus 8; p-value is 0.044) and non-fatal MI at Day 7 (1 versus 8; p-value is 0.044), and refractory ischaemia at the end of one month (14 versus 24; p-value is 0.04) and three months (25 versus 36; p-value is less than 0.01) in patients receiving tirofiban as compared to those receiving a placebo.

CONCLUSION

It may be concluded that tirofiban has a definite role in improving the outcome of patients with high-risk NSTE ACS.

Adenomyosis: still largely under-diagnosed

Underlying adenomyosis is often the cause of treatment failure for patients undergoing Mirena insertion, endometrial ablation and/or hysteroscopic resection for abnormal uterine bleeding and/or pelvic pain. In this cohort of abnormal uterine bleeding, clinicians rarely considered adenomyosis as a differential diagnosis. In such cases, gynaecologists concentrated primarily on menstrual flow. Symptoms of pelvic pain, dyspareunia, pelvic pressure symptoms and type of dysmenorrhoea were not queried. Frequently, no correlation was sought to account for a uterus noted to be enlarged either clinically or at hysteroscopy. Given the limitation of ultrasound scan (USS) in diagnosing adenomyosis, and gynaecologists' reliance on USS findings, adenomyosis often remains undiagnosed before a hysterectomy. An earlier diagnosis of adenomyosis requires a good history, correlation of clinical examination and ultrasound scan findings and a back-up MRI service. Once adenomyosis is suspected, women can be appropriately counselled so that they are fully aware of the possible failure of conservative management. If conservative management is chosen, they should be followed-up and hysterectomy offered for persistent symptoms.

A diagnostic dilemma: functioning noncommunicating uterine horn and elevated levels of CA125

BACKGROUND

Müllerian duct abnormalities are important to diagnose, considering the various clinical manifestations, implications for reproductive life, different treatment options, and prognoses. However, they are often difficult to diagnose, especially by noninvasive means. Here we discuss the diagnostic difficulty incurred in a case of unicornuate uterus with functioning noncommunicating horn having a high level of cancer antigen 125 as a presenting feature.

CASE

Unicornuate uterus with raised serum CA125.

CONCLUSIONS

Mullerian duct anomaly can be a differential diagnosis in women with adnexal mass and elevated CA125.

Siva is an apoptosis-selective p53 target gene important for neuronal cell death

p53 plays a central role in neuronal cell death resulting from acute injury or disease. To define the pathway by which p53 triggers apoptosis, we used microarray analysis to identify p53 target genes specifically upregulated during apoptosis but not cell cycle arrest. This analysis identified a small subset of targets highly selective for the p53 apoptotic response, including Siva, a proapoptotic protein whose function is not well understood. Siva's expression pattern suggests that it plays an instructive role in apoptosis, and accordingly, we demonstrate that Siva is essential for p53-dependent apoptosis in cerebellar granule neurons. In addition, we determine that endogenous Siva is associated with the plasma membrane and that Caspase-8 and Bid are important for neuronal apoptosis. Our studies highlight the participation of membrane signaling events in p53's apoptotic program in primary neurons and have significant implications for understanding the mechanisms underlying pathogenesis after neuronal injury and in neurodegenerative diseases.

Studies on codon usage inThermoplasma acidophilum and its possible implications on the occurrences of lateral gene transfer

Codon usage studies have been carried out on the coding sequences of Thermoplasma acidophilum, which is an archaeon and grows at very low pH and high temperature. Overall codon usage data analysis indicates that all the four bases are almost equifrequent at the third position of codons, which is expected (since genomic GC % of this genome is about 46%). However, multivariate statistical analysis indicates that there are two major trends in the codon usage variation among the genes in this organism. In the first major trend it is observed that genes having G and C ending codons are clustered at one end while, A and T ending ones are clustered at the other end. We have also found a significant positive correlation between the expressivities of genes and GC contents at the synonymous third codon positions. In the second major trend, it is seen that the genes are clustered into three distinct parts. A comparative analyses of codon usage data of T. acidophilum and Sulfolobus solfataricus reveals that one of the three clusters of genes of T. acidophilum is very similar to a considerable number of S. solfataricus genes, suggesting possible occurrences of lateral gene transfer between these two microorganisms as reported by earlier workers.

Investigation on the causes of codon and amino acid usages variation between thermophilic Aquifex aeolicus and mesophilic Bacillus subtilis

Base composition, codon usages and amino acid usages have been analyzed by taking 529 orthologous sequences of Aquifex aeolicus and Bacillus subtilis, having different optimal growth temperatures. These two bacteria do not have significant difference in overall GC composition, but GC(1+2) and GC3 levels were found to vary significantly. Significant increments in purine content and GC3 composition have been observed in the coding sequences of Aquifex aeolicus than its Bacillus subtilis counterparts. Correspondence analyses on codon and amino acid usages reveal that variation in base composition actually influences their codon and amino acid usages. Two selection pressures acting on the nucleotide level (GC3 and purine enrichment), causes variation in the amino acid usage differently in different protein secondary structures. Our results suggest that adaptation of amino acid usages in coil structure of Aquifex aeolicus proteins is under the control of both purine increment and GC3 composition, whereas the adaptation of the amino acids in the helical region of thermophilic bacteria is strongly influenced by the purine content. Evolutionary perspectives concerning the temperature adaptation of DNA and protein molecules of these two bacteria have been discussed on the basis of these results.

Evolutionary forces in shaping the codon and amino acid usages in Blochmannia floridanus

Endosymbiotic relationship has great effect on ecological system. Codon and amino acid usages bias of endosymbiotic bacteria Blochmannia floridanus (whose host is an ant Camponotus floridanus) was investigated using experimentally known genes of this organism. Correspondence Analysis on RSCU values show that there exists only one single explanatory major axis that is linked to the strand specific mutational biases. Majority of the genes have a tendency to concentrate on the leading strand, which may be related to the adaptive property related to the replication mechanisms. Amino acid usages were markedly different between the highly and lowly expressed genes in this organism and in particular, GC rich amino acids were found to occur significantly higher in highly expressed genes than the lowly expressed genes. Comparative analyses of the orthologous genes of Escherichia coli and Blochmannia floridanus show that highly expressed genes are significantly more conserved than lowly expressed genes. Based on our results we concluded that strand specific mutational bias is strongly operational in selecting the codon usage in this organism. Replicational-transcriptional selection can be invoked from the presence of majority of highly expressed genes in the leading strand. Conservation of GC rich amino acids in the highly expressed genes to its ancestor is the major source of variation in amino acid usages in the organism. Hydrophobicity of the genes is the second major source in differentiating the genes according to their amino acid usages in this organism.

A partial sequence of lipoxygenase gene from genomic DNA of aromatic rice (Oryza sativa L.)

Aromatic (Bas-370, PB-1) and non-aromatic (Pusa-677, Pusa-834) rice were selected for the characterization and for distribution of lipoxygenase (Lox) genes. Polymorphism was observed when genomic DNA of rice varieties was hybridized with a heterologous lipoxygenase probe. A distinct polymorphic fragment (approximately 1.2 kb) was found in Bas-370. Sub-genomic library of Bas-370 was constructed and screened with LoxA probe. The smallest putative clone (pBas-14) of approximately 1.2 kb was sequenced. Complete nucleotide and deduced amino acid sequence showed the clone was 1134 bp long and comprised of 378 amino acid residues. PCR amplification of genomic DNA from four rice varieties with a soybean Lox primer also showed a polymorphic fragment of size approximately 600 bp (amplicon) in aromatic varieties that was sequenced directly. Nucleotide sequence alignment between pBas-14 and amplicon concluded that the amplicon was a part of the insert pBas-14.

Power Doppler ultrasonography for the evaluation of skin tumors other than malignant melanoma

The purpose of this prospective study was to evaluate the value of power Doppler ultrasonography (PDUS) in assessing the vascularity of skin tumors other than malignant melanoma, and to investigate possible diagnostic criteria to help to distinguish malignant from benign tumors preoperatively. Seventy-one patients with the clinical diagnosis of a skin tumor were initially evaluated by ultrasonography. Then PDUS was performed and the presence and type of vascularity (peripheral or mixed) were investigated. Of the 19 benign and 52 malignant lesions, 3 could not be visualized with US. Forty-nine lesions were found to have vascularity (21 peripheral, 28 mixed-type) on PDUS. Of the malignant lesions, 26 showed mixed and 17 showed peripheral-type vascularity; for benign lesions these numbers were 2 and 4 respectively. The presence of vascularity correlated well with pathological behavior (malignant versus benign) (P = 0.00002), width (P = 0.0001), thickness (P = 0.001), dermal disruption (P = 0.0018), and subdermal extension (P = 0.002) of the tumor; however, the type of vascularity correlated only with thickness (P = 0.014). In relation to malignancy, the sensitivity of the presence of vascularity on PDUS was 88% and the specificity was 63%. These values were 93% and 40% respectively, for the mixed type of vascularity when it was accepted as a feature of malignancy. PDUS may help to distinguish malignant from benign skin tumors during preoperative evaluation.

DNA unwinding mechanism for the transcriptional activation of momP1 promoter by the transactivator protein C of bacteriophage Mu

Transcription factor-induced conformational changes in DNA are one of the mechanisms of transcription activation. C protein of bacteriophage Mu appears to transactivate the mom gene of the phage by this mode. DNA binding by C to its site leads to torsional changes that seem to compensate for a weak momP1 promoter having a suboptimal spacing of 19 bp between the poor -35 and -10 elements. The C-mediated unwinding could realign the promoter elements for RNA polymerase recruitment to the reoriented promoter. In this study, the model has been tested by mutational analysis of the spacer region of momP1 and by assessing the strength of the mutant promoters. The response to C-mediated transactivation was dependent on the spacer length of the promoters. Mutants with 17-bp spacing between the two promoter elements showed reduced activity in the presence of the transactivator as compared with their basal level. A synthetic promoter with near consensus promoter elements and optimal 17-bp spacing was also tested to evaluate the model. The results imply a role for C-mediated unwinding in mom transcription activation.

A versatile in vivo footprinting technique using 1,10-phenanthroline-copper complex to study important cellular processes

A number of reagents have been used to define the sequence-specific protein-DNA contacts by footprinting analysis. We report a new in vivo technique using the complex of 1,10-phenanthroline and copper [(OP(2))Cu] as a probe to study various intracellular DNA-protein interactions in whole cells. The versatility of the protocol is demonstrated by applying the technique to address various processes. The protocol is applied to (i) detect structural alterations in DNA as a result of single base substitution, (ii) footprint site-specific DNA-binding proteins, (iii) analyze promoter occupancy by RNA polymerase and (iv) analyze molecular interactions during transcription initiation. The results demonstrate that in vivo (OP)(2)Cu probing is a useful tool in studying important cellular processes involving DNA-protein interactions and has potential applications in post-genomic research.

Methyl (SR)-10-chloro-1,2,3,4,5,6-hexahydro-6-hydroxy-8-methoxy-1-methyl-1,9-phenanthroline-6-carboxylate

In the title compound, C(16)H(19)ClN(2)O(4), the pyridine ring is nearly planar, the piperidine ring is non-planar and the cyclohexane ring adopts a screw-boat conformation. The carboxylate group makes a dihedral angle of 80.9 (2) degrees with the least-squares plane through the cyclohexane ring.

Effect of osmolytes and chaperone-like action of P-protein on folding of nucleocapsid protein of Chandipura virus

Amino acid sequences of nucleocapsid proteins are mostly conserved among different rhabdoviruses. The protein plays a common functional role in different RNA viruses by enwrapping the viral genomic RNA in an RNase-resistant form. Upon expression of the nucleocapsid protein alone in COS cells and in bacteria, it forms large insoluble aggregates. In this work, we have reported for the first time the full-length cloning of the N gene of Chandipura virus and its expression in Escherichia coli in a soluble monomeric form and purification using nonionic detergents. The biological activity of the soluble recombinant protein has been tested, and it was found to possess efficient RNA-binding ability. The state of aggregation of the recombinant protein was monitored using light scattering. In the absence of nonionic detergents, it formed large aggregates. Aggregation was significantly reduced in the presence of osmolytes such as d-sorbitol. Aggregate formation was suppressed in the presence of another viral product, phosphoprotein P, in a chaperone-like manner. Both the osmolyte and phosphoprotein P also suppressed aggregation to a great extent during refolding from a guanidine hydrochloride-denatured form. The function of the phosphoprotein and osmolyte appears to be synergistic to keep the N-protein in a soluble biologically competent form in virus-infected cells.

Intrinsic DNA distortion of the bacteriophage Mu momP1 promoter is a negative regulator of its transcription. A novel mode of regulation of toxic gene expression

The momP1 promoter of the bacteriophage Mu mom operon is an example of a weak promoter. It contains a 19-base pair suboptimal spacer between the -35 (ACCACA) and -10 (TAGAAT) hexamers. Escherichia coli RNA polymerase is unable to bind to momP1 on its own. DNA distortion caused by the presence of a run of six T nucleotides overlapping the 5' end of the -10 element might prevent RNA polymerase from binding to momP1. To investigate the influence of the T(6) run on momP1 expression, defined substitution mutations were introduced by site-directed mutagenesis. In vitro probing experiments with copper phenanthroline ((OP)(2)Cu) and DNase I revealed distinct differences in cleavage patterns among the various mutants; in addition, compared with the wild type, the mutants showed an increase (variable) in momP1 promoter activity in vivo. Promoter strength analyses were in agreement with the ability of these mutants to form open complexes as well as to produce momP1-specific transcripts. No significant role is attributed to the overlapping and divergently organized promoter, momP2, in the expression of momP1 activity, as determined by promoter disruption analysis. These data support the view that an intrinsic DNA distortion in the spacer region of momP1 acts in cis as a negative element in mom operon transcription. This is a novel mechanism of regulation of toxic gene expression.