Management of Acute Pulmonary Embolism: Consensus Statement for Indian Patients.

Pulmonary embolism (PE) is an important cause of morbidity and mortality among hospitalized patients. Although the exact epidemiology of PE is not known in India, Some of the studies show that more frequently it is missed and not managed appropriately leading to significant cardiovascular morbidity and mortality. Justification and purpose: Indian guidelines for the diagnosis and treatment of acute PE are not yet formulated. The objective of this consensus statement is to propose a diagnostic and management approach for acute PE in India. PROCESS: A working group of 15 experts in the management of acute PE (cardiologists, pulmonologist, haematologist, emergency specialist and intensivists). This consensus statement makes recommendations for diagnosis and management for PE based on literature review, including Indian data.

Similar response patterns to topical minoxidil foam 5% in frontal and vertex scalp of men with androgenetic alopecia: a microarray analysis.

BACKGROUND: There are regional variations in the scalp hair miniaturization seen in androgenetic alopecia (AGA). Use of topical minoxidil can lead to reversal of miniaturization in the vertex scalp. However, its effects on other scalp regions have been less well studied. OBJECTIVES: To determine whether scalp biopsies from men with AGA show variable gene expression before and after 8 weeks of treatment with minoxidil topical foam 5% (MTF) vs. placebo. METHODS: A placebo-controlled double-blinded prospective pilot study of MTF vs. placebo was conducted in 16 healthy men aged 18-49 years with Hamilton-Norwood type IV-V thinning. The subjects were asked to apply the treatment (active drug or placebo) to the scalp twice daily for 8 weeks. Stereotactic scalp photographs were taken at the baseline and final visits, to monitor global hair growth. Scalp biopsies were taken at the leading edge of hair loss from the frontal and vertex scalp before and after treatment with MTF and placebo, and microarray analysis was performed using the Affymetrix GeneChip HG U133 Plus 2.0. RESULTS: Global stereotactic photographs showed that MTF induced hair growth in both the frontal and vertex scalp of patients with AGA. Regional differences in gene expression profiles were observed before treatment. However, MTF treatment induced the expression of hair keratin-associated genes and decreased the expression of epidermal differentiation complex and inflammatory genes in both scalp regions. CONCLUSIONS: These data suggest that MTF is effective in the treatment of both the frontal and vertex scalp of patients with AGA.

MAGIC Tool: integrated microarray data analysis.

SUMMARY: Several programs are now available for analyzing the large datasets arising from cDNA microarray experiments. Most programs are expensive commercial packages or require expensive third party software. Some are freely available to academic researchers, but are limited to one operating system. MicroArray Genome Imaging and Clustering Tool (MAGIC Tool) is an open source program that works on all major platforms, and takes users 'from tiff to gif'. Several unique features of MAGIC Tool are particularly useful for research and teaching. AVAILABILITY: http://www.bio.davidson.edu/MAGIC

Tuberculosis of temporomandibular joint.

Tuberculosis of the temporomandibular joint is a very rare disease. Its close relation to the parotid can cause diagnostic confusion. This case is being reported keeping this point in view.

Loss of heterozygosity at chromosome 11p15 in Wilms tumors: identification of two independent regions.

Loss of heterozygosity (LOH) on the short arm of chromosome 11 is the most frequent genetic alteration in Wilms tumors, indicating that one or more tumor suppressor genes that map to this chromosomal region are involved in the development of the disease. The WT1 gene located on 11p13 has been characterized but mutations in this gene occur in only about 10% of Wilms tumors. A second locus (WT2) at chromosome 11p15 has also been described in Wilms tumors but thus far efforts to clone the WT2 gene(s) have been frustrated by the large size (approximately 10 Mb) of this region. Using a high-density marker LOH analysis of 11p15.5-15.4, we have refined the location of a Wilms tumor suppressor gene between the markers D11S1318-D11S1288 (approximately 800 kb) within 11p15.5. We have also identified a second, novel region of LOH that spans the markers D11S1338-D11S1323 (approximately 336 kb) at 11p15.5-p115.4. Thus a second distinct locus, in addition to the previously defined WT2, on chromosome 11p15.5, appears to play a role in the development of Wilms tumors.

Two distinct tumor suppressor loci within chromosome 11p15 implicated in breast cancer progression and metastasis.

Chromosome 11p15 has attracted considerable attention because of the biological importance of this region to human disease. Apart from being an important tumor suppressor locus showing loss of heterozygosity (LOH) in several adult and childhood cancers, 11p15 has been shown by linkage analysis to harbor the gene(s) for the Beckwith-Wiedemann syndrome. Furthermore, the clustering of known imprinted genes in the 11p15.5 region suggests that the target gene may also be imprinted. However, positional cloning efforts to identify the target genes have been complicated by the large size (approximately 10 Mb) and complexity of LOH at 11p15. Here, we have analyzed 94 matched normal and breast tumor samples using 17 polymorphic markers that map to 11p15.5-15.4. We have defined precisely the location of a breast tumor suppressor gene between the markers D11S1318 and D11S4088 (approximately 500 kb) within 11p15.5. LOH at this region occurred in approximately 35-45% of breast tumors analyzed. In addition, we have fine-mapped a second, critical region of LOH, that spans the markers D11S1338-D11S1323 (approximately 336 kb) at 11p15.5-p15.4, that is lost in approximately 55-60% of breast tumors. There is a striking correlation between the loss of the two 11p loci and the clinical and histopathological features of breast tumors. LOH at region 1 correlated significantly (P = 0.016) with early events in malignancy and invasiveness. In contrast, the loss of the more proximal region 2, is highly predictive (P = 0.012) of aggressive metastatic disease. Thus, two distinct tumor suppressor loci on chromosome 11p15 may contribute to tumor progression and metastasis in breast cancer. The fine mapping of this intriguing chromosomal region should facilitate the cloning of the target genes and provide critical clues to understanding the mechanisms that contribute to the evolution of adult and childhood cancers.

Microsatellite instability at a single locus (D11S988) on chromosome 11p15.5 as a late event in mammary tumorigenesis.

Replication errors at microsatellite repeats are markers for genomic instability in hereditary nonpolyposis colon carcinoma and in some sporadic cancers. Microsatellite sequences may show alterations in one or both alleles in some tumors, suggesting an error in the DNA replication of dinucleotide repeats. We have investigated microsatellite instability (MSI) in sporadic breast tumors at several loci on the short arm of chromosome 11. Among microsatellites studied we found a high frequency of MSI at one specific locus, D11S988 on chromosome 11p15.5. Most colorectal tumors that exhibit MSI display abnormalities of at least one other locus and usually more. By contrast we have detected only one abnormal microsatellite in all the tumors examined. This marker lies between the TH and HBB genes, a subregion previously suggested to harbor a putative tumor suppressor gene for breast cancer. Loss of heterozygosity for chromosome markers at 11p15 has earlier been correlated with poor prognosis. In an unselected panel of primary breast tumors, we observed that 20 of 69 showed mobility shifts of D11S988 in tumor compared with corresponding normal DNA samples. Tumors with instability at D11S988 were rapidly proliferating compared with tumors without MSI. DNA aneuploidy, estrogen receptor positivity and moderate to poorly differentiated tumor phenotype were also characteristics of tumors with MSI at this locus and the majority also exhibited loss of heterozygosity at one or more of the six 11p loci analyzed. Taken together these data suggest that MSI at the D11S988 locus is a late event in mammary tumorigenesis and may be associated with progression of breast carcinomas.

Antimalarial activity of novel ring-contracted artemisinin derivatives.

Bromoacetal 2 undergoes a novel ring-contracted reaction to give the aldehyde 3 in the presence of DBU or triethylamine. The aldehyde 3 is reduced to the alcohol 4 and oxidized to the carboxylic acid 5. The alcohol 4 reacts with dihydroartemisinin to give the two diastereoisomers 38 and 39. All the compounds were tested for antimalarial activity in mice infected with chloroquine sensitive Plasmodium berghei. If the activity of a compound was comparable to that of the standard compound, such as arteether, it was tested against chloroquine resistant NS strain infection in mice. Initially the compounds were administered subcutaneously, and if found to be active, they were tested by oral route. The antimalarial activity of compounds 19, 38, and 39 was found to be comparable to that of arteether when tested in K-173-infected mice. They were also active against chloroquine resistant NS strain infection in mice.

Estrogen receptor mutations in tamoxifen-resistant breast cancer.

Clinical resistance to antiestrogens like tamoxifen is a major problem in the treatment of hormone-dependent breast cancers. Since the estrogen receptor plays a central role in mediating the effects of estrogens and antiestrogens, we hypothesized that mutations in the estrogen receptor could be one mechanism by which breast tumors evolve from a hormone-dependent to a hormone-independent phenotype. The eight exons of the estrogen receptor complementary DNA from 20 tamoxifen-resistant and 20 tamoxifen-sensitive tumors were screened by Single Strand Conformation Polymorphism (SSCP), and the variant conformers were sequenced to identify the nucleotide changes. A 42-base pair replacement was found in exon 6 of a tamoxifen-resistant tumor. A single base pair deletion in exon 6 of a tamoxifen-resistant metastatic tumor but not in the primary tumor was detected in another case. If translated, both these mutations could generate truncated receptors with an intact DNA-binding domain and a defective hormone-binding domain that could constitutively activate transcription of previously estrogen-responsive genes. The remaining 18 of 20 tamoxifen-resistant tumors did not contain mutations in any of the 8 exons of the estrogen receptor complementary DNA. These results suggest that mutations in the estrogen receptor occur at a low frequency and do not account for most estrogen-independent, tamoxifen-resistant breast tumors.

Somatostatin inhibition of gastrin gene expression: involvement of pertussis toxin-sensitive and -insensitive pathways.

These studies were performed to determine the intracellular pathways involved in regulating gastrin gene expression. The inclusion of 10(-4) M forskolin or 10(-4) M dibutyryl cyclic AMP (DBcAMP) in incubation medium containing dog antral mucosa resulted in 249% and 323% increases, respectively, in gastrin mRNA levels. The stimulatory effects of forskolin and DBcAMP were both inhibited significantly by 10(-6) M somatostatin. Preincubation of antral mucosa with pertussis toxin nearly abolished the inhibitory effects of somatostatin on gastrin mRNA stimulated by forskolin, but had no effect following DBcAMP. To examine whether calcium-dependent pathways might be involved in regulating gastrin gene expression, antral mucosa was incubated with increasing concentrations of calcium or the ionophore ionomycin. Both agents produced only modest increases in gastrin mRNA, which were abolished by the addition of somatostatin to the incubation medium. These studies indicate that somatostatin appears to inhibit gastrin gene expression through mechanisms involving both pertussis toxin-sensitive and -insensitive pathways.

The effects of peptide histidine isoleucine on antral gastrin and somatostatin.

The present studies were directed to determine whether peptide histidine isoleucine (PHI) affects expression of the gastrin and somatostatin genes and whether such effects may be functionally linked. In separate experiments, the effects of PHI on medium gastrin and somatostatin concentrations, the incorporation of 35S-labelled amino acids into newly synthesized gastrin and somatostatin, and steady state gastrin and somatostatin mRNA were determined. PHI inhibited basal expression of the gastrin gene at all levels examined, while no significant effect on basal somatostatin gene expression could be detected. PHI also decreased carbachol-stimulated antral gastrin release and simultaneously increased somatostatin release. However, in contrast to its structural analogues, secretin and gastric inhibitory peptide, the immunoneutralization of endogenous somatostatin by the administration of specific antibodies did not affect significantly the capacity of PHI to inhibit gastrin release into the culture medium stimulated by carbachol. The results of these studies indicate that PHI exerts a physiological inhibitory effect on antral gastrin cells and that this inhibition may occur at several steps along the biosynthetic pathway. In addition, unlike its structural analogues, PHI inhibition of carbachol-stimulated gastrin release is not functionally linked to its stimulatory effects on somatostatin release.

Efficacy of carbamazepine in premenstrual syndromes. A report on four cases.

Five patients presented with severe mood disturbance and behaviour change during the premenstruum. Suspiciousness was an important feature in four of them. They were treated with carbamazepine 200-400 mg orally at bedtime for 7 days before the onset of menses. The follow-up period varied from 1 1/2 years to 2 menstrual cycles. Four patients showed remarkable improvement; one patient dropped out because of allergic rash.

Somatostatin stimulates gastrin mRNA turnover in dog antral mucosa.

Previous studies have demonstrated that antral somatostatin exerts inhibitory effects on gastrin cells via paracrine pathways, accomplished by its release from somatostatin-containing cells into the immediate interstitial environment of the gastrin cell. The present studies were directed to examine the effect of somatostatin on gastrin gene transcription in the dog antrum and to determine whether somatostatin modulates gastrin mRNA turnover. In response to the immunoneutralization of endogenous antral somatostatin, basal gastrin gene transcriptional activity increased by 34 +/- 3.3% (p less than 0.01). Moreover, somatostatin significantly inhibited gene transcription that had been stimulated by dibutyryl-cAMP and carbachol. To determine the effect of somatostatin on gastrin mRNA turnover, antral mucosal fragments were incubated with antibodies to somatostatin, total RNA was extracted, and gastrin mRNA was measured at several time points. Following the immunoneutralization of antral somatostatin, maximum induction was achieved at 60 min, at which time gastrin mRNA levels had increased by 184 +/- 6.0% (p less than 0.01). At that time, a somatostatin analogue which is biologically active, but nonimmunoreactive with the antiserum, was added to the incubation medium. The analogue produced a prompt and steady de-induction of gastrin mRNA concentration, which returned to basal levels by 120 min. Regression analysis of RNA induction and de-induction profiles demonstrated a 292 +/- 40.6% increase (p less than 0.01) in gastrin mRNA turnover induced by somatostatin. In separate experiments antral mucosa was incubated with cycloheximide, both in the presence and absence of somatostatin antibodies. Incubation in the presence of cycloheximide resulted in a 52.3 +/- 8.4% (p less than 0.01) increase in gastrin mRNA levels under basal conditions, but had no effect following antral somatostatin immunoneutralization. Our results indicate that, although somatostatin inhibits gastrin gene transcription, its predominant effect on gastrin gene expression appears to occur at the posttranscriptional level by increasing the turnover of gastrin mRNA.

Inhibition of antral gastrin cells by peptide histidine isoleucine.

The present studies were directed to determine whether peptide histidine isoleucine (PHI), like its structural analogues secretin and gastric inhibitory peptide, inhibits antral gastrin. In separate experiments, the effects of PHI on medium gastrin concentrations, the incorporation of [35S]methionine into newly synthesized gastrin, and steady-state gastrin mRNA were determined. The inclusion of PHI in the incubation medium decreased medium gastrin levels at all concentrations examined, an effect that was not altered by the addition of 10(-6) M tetrodotoxin to the medium. PHI also inhibited the incorporation of [35S]methionine into newly synthesized gastrin in a concentration-dependent manner. Steady-state levels of gastrin mRNA were determined by dot-blot hybridization, using a 32P-labeled gastrin cRNA probe. PHI inhibited gastrin mRNA levels in a concentration-dependent manner; in contrast, no effect on the levels of actin and ubiquitin mRNA could be detected, indicating specificity of PHI on gastrin mRNA. The results of these studies indicate that PHI may exert a physiological inhibitory effect on antral gastrin cells and that this inhibition may occur at several steps along the biosynthetic pathway.

Inhibition of gastrin gene expression by somatostatin.

Previous studies performed in this laboratory have demonstrated somatostatin-containing cells in close proximity to gastrin cells in antral mucosa and have shown that somatostatin exerts a local regulatory effect on gastrin release. The present studies were directed to determine whether the effects of somatostatin on the antral gastrin cell involve pretranslational events. The effects of somatostatin on gastrin mRNA were determined by dot blot hybridization using a gastrin antisense RNA probe derived from human gastrin cDNA. Inclusion of somatostatin in the incubation medium caused a dose-dependent inhibition of steady-state gastrin mRNA. Conversely, when antral somatostatin was neutralized by the addition of specific somatostatin antibodies to the incubation medium, gastrin mRNA levels increased by 116 +/- 31% over control values (P less than 0.01). Northern blot hybridization of total antral RNA demonstrated a single major band with a molecular size of approximately 620 nucleotides, closely matching the predicted size of gastrin mRNA. The effect of somatostatin on the rate of gastrin gene transcription was examined using nuclear run-off transcription assays. Inclusion of antibodies to somatostatin in the incubation medium resulted in a 33.8 +/- 3.3% increase in gastrin gene transcriptional activity (P less than 0.01). These studies indicate that, in addition to its established effect on peptide release, somatostatin exerts inhibitory effects on antral gastrin cells at the pretranslational level. Although this inhibition appears to occur in part at the gene transcriptional level, the results also indicate that somatostatin may affect posttranscriptional processing of gastrin mRNA.

3'-terminal polyadenylate sequences of Escherichia coli tryptophan synthetase alpha-subunit messenger RNA.

Our earlier studies have shown that the mRNA from many bacterial species, including Escherichia coli and Bacillus subtilis, is extensively polyadenylated, but with shorter poly(A) segments than those associated with eukaryotic mRNA. In this paper, we show that about 40% of the mRNA for the tryptophan synthetase alpha-subunit (TrpA) of E. coli carries a 3'-terminal polyadenylate sequence of 15 to 20 residues. This conclusion was supported by several independent lines of evidence. About 40% of trpA mRNA bound to oligo(dT)-cellulose at high ionic strength and was eluted with water. Treatment with RNase H in the presence of oligo(dT)12-18 destroyed the ability of trpA mRNA to bind to oligo(dT)-cellulose, presumably through the degradation of the poly(A) tract. trpA mRNA could be used as template for complementary DNA synthesis with reverse transcriptase in a reaction that was absolutely dependent on oligo(dT)12-18 as primer. The identity of the cDNA product as a complement to trpA mRNA was established by specific hybridization. In addition, it was possible to synthesize polyadenylated trpA mRNA in toluene-permeabilized cells of E. coli transformed with a recombinant plasmid carrying the trpA gene. In view of the fact that the trpA gene and its 3'-untranslated region contain no continuous deoxyadenylate sequences larger than five nucleotides, one can conclude that the polyadenylate moiety is added post-transcriptionally.

Messenger ribonucleic acid for the lipoprotein of the Escherichia coli outer membrane is polyadenylated.

Earlier studies had shown that a large portion of bacterial messenger RNA carries 3'-terminal polyadenylate sequences, albeit of somewhat shorter length than those associated with eukaryotic mRNA. In this paper, we show for the first time that a specific prokaryotic mRNA is polyadenylated. Three independent lines of evidence demonstrate that a 3'-terminal polyadenylate sequence 10 to 15 nucleotides in length is associated with about 40% of the mRNA of the outer membrane lipoprotein of Escherichia coli: 40% of lipoprotein mRNA binds to oligodeoxythymidylate-substituted cellulose at high ionic strength and is eluted by water; treatment of lipoprotein mRNA with oligodeoxythymidylate and ribonuclease H destroys its ability to bind to oligodeoxythymidylate-cellulose; and in the presence of oligodeoxythymidylate, lipoprotein mRNA can serve as template for the synthesis of DNA complementary to lipoprotein mRNA by reverse transcriptase. In view of the fact that the lpp gene and its downstream-flanking region contain no continuous deoxyadenylate sequences longer than five nucleotides, the polyadenylate moiety must be added post-transcriptionally. It was possible to demonstrate the synthesis of polyadenylated lipoprotein mRNA in toluene-permeabilized cells of E. coli, opening the way for the study of its biosynthesis.

DNA-binding abilities of bisguanylhydrazones of anthracene-9,10-dicarboxaldehyde.

DNA-binding strengths of three anthracene-9,10-dicarboxaldehyde hydrazones were examined by spectral shifts of the drug-DNA combinations, spectral titration by Scatchard plots, elevation of DNA melting temperature during complexation and comparison of spectral shifts in the presence of DNA's having variable base contents. Dissociation of the DNA-complexes was also observed. The results showed a strong degree of binding by the three compounds. They did not exhibit noticeable base-pair specificity, but both associated with and dissociated rapidly from DNA. Scatchard plots for DNA association indicated two types of binding; the stronger was most likely due to intercalation of the planar anthracene ring into the DNA double helix. No direct correlation can be drawn between the observed anti-cancer activities and DNA binding affinities of these compounds in vitro.

Construction of a cDNA library from polyadenylated RNA of Bacillus subtilis and the determination of some 3'-terminal sequences.

We had found previously that polyadenylated RNA constitutes a surprisingly large fraction of mRNA in both Escherichia coli and Bacillus subtilis [Gopalakrishna et al., Nucl. Acids Res. 9 (1981) 3545-3554; Biochem. 21 (1982) 2724-2729]. We have also shown [Gopalakrishna and Sarkar, J. Biol. Chem. 257 (1982) 2747-2750] that polyadenylated RNA from B. subtilis can serve as a template for the synthesis of complementary DNA by reverse transcriptase using oligo(dT) as primer. In this work, we show that the cDNA thus synthesized contains sequences representative of poly(A)+RNA and can serve as template for double-stranded (ds) cDNA synthesis. The ds cDNA could be inserted into the PstI site of pBR322 and cloned in E. coli DH1. The cDNA inserts from a few cloned recombinant pBR322 plasmids were transferred to M13mp18 bacteriophage for sequence determination. Six cDNA species had terminal oligo(dT) sequences, indicating that they represented the complement of poly(A)+RNA. This constitutes independent and direct evidence for the existence of bacterial polyadenylated mRNA and opens the way for studying the nucleotide sequences that control polyadenylation.