Transcriptomic analysis of resistance and short-term induction response to pyrethroids, in Anopheles coluzzii legs

BACKGROUND

Insecticide-treated bed nets and indoor residual spraying comprise the major control measures against Anopheles gambiae sl, the dominant vector in sub-Saharan Africa. The primary site of contact with insecticide is through the mosquitoes' legs, which represents the first barrier insecticides have to bypass to reach their neuronal targets. Proteomic changes and leg cuticle modifications have been associated with insecticide resistance that may reduce the rate of penetration of insecticides. Here, we performed a multiple transcriptomic analyses focusing on An. coluzzii legs.

RESULTS

Firstly, leg-specific enrichment analysis identified 359 genes including the pyrethroid-binder SAP2 and 2 other chemosensory proteins, along with 4 ABCG transporters previously shown to be leg enriched. Enrichment of gene families included those involved in detecting chemical stimuli, including gustatory and ionotropic receptors and genes implicated in hydrocarbon-synthesis. Subsequently, we compared transcript expression in the legs of a highly resistant strain (VK7-HR) to both a strain with very similar genetic background which has reverted to susceptibility after several generations without insecticide pressure (VK7-LR) and a lab susceptible population (NG). Two hundred thirty-two differentially expressed genes (73 up-regulated and 159 down-regulated) were identified in the resistant strain when compared to the two susceptible counterparts, indicating an over-expression of phase I detoxification enzymes and cuticular proteins, with decrease in hormone-related metabolic processes in legs from the insecticide resistant population. Finally, we analysed the short-term effect of pyrethroid exposure on An. coluzzii legs, comparing legs of 1 h-deltamethrin-exposed An. coluzzii (VK7-IN) to those of unexposed mosquitoes (VK7-HR) and identified 348 up-regulated genes including those encoding for GPCRs, ABC transporters, odorant-binding proteins and members of the divergent salivary gland protein family.

CONCLUSIONS

The data on An. coluzzii leg-specific transcriptome provides valuable insights into the first line of defense in pyrethroid resistant and short-term deltamethrin-exposed mosquitoes. Our results suggest that xenobiotic detoxification is likely occurring in legs, while the enrichment of sensory proteins, ABCG transporters and cuticular genes is also evident. Constitutive resistance is primarily associated with elevated levels of detoxification and cuticular genes, while short-term insecticide-induced tolerance is linked with overexpression of transporters, GPCRs and GPCR-related genes, sensory/binding and salivary gland proteins.

Primary progression in NMOSD. Does it really exist?

Acute myelitis, in conjunction with a longitudinally extensive MRI pattern, is a core feature of aquaporin 4 IgG-associated neuromyelitis optica spectrum disorders (NMOSD). According to current diagnostic criteria for transverse myelitis and NMOSD, clinical worsening should not exceed 3-4 weeks from attack onset. Recently, we were able to document, through frequent clinical examination and radiological follow-up, the unusual case of an ab initio progressive myelopathy, ultimately attributed to aquaporin-4 autoimmunity. Although this case might merely represent an overlooked cluster of individual clinical attacks, it could, however, draw attention to the controversial concept of disease progression in the context of NMOSD.

Efficient genome editing in the olive fruit fly, Bactrocera oleae

The olive fruit fly, Bactrocera oleae, causes great damage to the quality and quantity of olive production worldwide. Pest management approaches have proved difficult for a variety of reasons, a fact that has brought about a need for alternative tools and approaches. Here we report for the first time in B. oleae the development of the clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) gene editing tool, using the well-known eye colour marker gene scarlet. Two synthetic guide RNAs targeting the coding region of the scarlet gene were synthesized and shown to work efficiently in vitro. These reagents were then microinjected along with purified Cas9 protein into early-stage embryos. Successful CRISPR-induced mutations of both copies of the scarlet gene showed a striking yellow eye phenotype, indicative of gene disruption. Multiple successful CRISPR events were confirmed by PCR and sequencing. The establishment of an efficient CRISPR-based gene editing tool in B. oleae will enable the study of critical molecular mechanisms in olive fruit fly biology and physiology, including the analysis of insecticide resistance mechanisms and the discovery of novel insecticide targets, as well as facilitate the development of novel biotechnology-based pest control strategies.

Vitamin D in mild cognitive impairment and Alzheimer's disease. A study in older Greek adults

BACKGROUND

In recent years, accumulating evidence has linked vitamin D deficiency to cognitive dysfunction and dementia. This study aimed at determining the relevance of serum 25-hydroxyvitamin D concentrations in mild cognitive impairment (MCI) and Alzheimer's disease (AD) in older Greek adults. It also examined whether the vitamin D level could be considered a predisposing factor for conversion from MCI to AD.

METHODS

The study enrolled 350 subjects aged 65 years and over, allocated into three groups consisting of 103 healthy subjects (HS), 109 individuals with MCI, and 138 patients with AD, respectively. Serum 25-hydroxyvitamin D [25(OH)D] concentrations, measured in ng/ml, were determined by electrochemiluminescence, and we used the Mini-Mental State Examination (MMSE) and the Cambridge Cognition Examination (CAMGOG) to evaluate the subjects' cognitive status. One follow-up examination was performed for the MCI patients 30 months ± three months after the initial evaluation.

RESULTS

Compared to HS, serum 25(OH)D levels were significantly decreased in individuals with MCI (p =0.012) and patients with AD (p <0.001). Moreover, serum 25(OH)D concentrations were significantly decreased in patients with AD compared to individuals with MCI (p =0.003) and also significantly lower in individuals with MCI who progressed to AD compared to those who remained MCI (p =0.028). After adjusting for confounders, multivariate analysis revealed that an increase of vitamin D concentration by one ng/mL reduces the risk of MCI by 4 % (OR =0.96, 95 % CI =0.92-0.99, p =0.006), the risk of AD by 8 % (OR =0.92, 95 % CI =0.89-0.95, p <0.001), and in an individual with MCI reduces the risk of conversion to AD by 10 % (OR =0.90, 95 % CI =0.83-0.96, p =0.003).

CONCLUSIONS

The present study reveals that serum vitamin D levels are significantly decreased in subjects with MCI and patients with AD compared to HS. Additionally, individuals with MCI who progressed to AD presented significantly lower vitamin D levels than those who remained MCI. These results suggest that preserving adequate vitamin D status in older adults could delay or prevent cognitive decline. HIPPOKRATIA 2020, 24(3): 120-126.

Enhanced genome assembly and a new official gene set for Tribolium castaneum

Background

The red flour beetle Tribolium castaneum has emerged as an important model organism for the study of gene function in development and physiology, for ecological and evolutionary genomics, for pest control and a plethora of other topics. RNA interference (RNAi), transgenesis and genome editing are well established and the resources for genome-wide RNAi screening have become available in this model. All these techniques depend on a high quality genome assembly and precise gene models. However, the first version of the genome assembly was generated by Sanger sequencing, and with a small set of RNA sequence data limiting annotation quality.

Results

Here, we present an improved genome assembly (Tcas5.2) and an enhanced genome annotation resulting in a new official gene set (OGS3) for Tribolium castaneum, which significantly increase the quality of the genomic resources. By adding large-distance jumping library DNA sequencing to join scaffolds and fill small gaps, the gaps in the genome assembly were reduced and the N50 increased to 4753kbp. The precision of the gene models was enhanced by the use of a large body of RNA-Seq reads of different life history stages and tissue types, leading to the discovery of 1452 novel gene sequences. We also added new features such as alternative splicing, well defined UTRs and microRNA target predictions. For quality control, 399 gene models were evaluated by manual inspection. The current gene set was submitted to Genbank and accepted as a RefSeq genome by NCBI.

Conclusions

The new genome assembly (Tcas5.2) and the official gene set (OGS3) provide enhanced genomic resources for genetic work in Tribolium castaneum. The much improved information on transcription start sites supports transgenic and gene editing approaches. Further, novel types of information such as splice variants and microRNA target genes open additional possibilities for analysis.

MOLECULAR TYPING OF MYCOBACTERIUM KANSASII — A GLOBAL PERSPECTIVE

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Long-term effects of prolonged-release fampridine in cognitive function, fatigue, mood and quality of life of MS patients: The IGNITE study

BACKGROUND

Studies have reported conflicting results regarding the potential benefit of prolonged release (PR) fampridine in other domains besides walking. Moreover, only a small number of studies have explored long- term effects of PR fampridine. The aim of this study was to assess cognitive function, quality of life, mood and fatigue in MS patients treated with fampridine after 6 and 12 months of treatment.

METHODS

IGNITE was an observational, open label study. Subjects were examined with the timed 25-ft walk (T25FW) and the BICAMS battery and were asked to complete the Multiple Sclerosis Impact Scale (MSIS-29), Modified Fatigue Impact Scale (MFIS), Beck Depression Inventory-II (BDI-II) and MS International Quality-of-Life questionnaire (MUSIQOL) at baseline and at weeks 24 and 48. Patients were sub-grouped into responders (n:40) and non-responders (n:20) according to T25FW performance after 2 weeks on treatment.

RESULTS

After 6 months, statistically significant improvement was observed on T25FW (p < .001), SDMT (p < .001) and MSIS29 (p < .001), for responders. After 1 year on treatment, statistically significant improvement was observed in T25FW (p < .001), MSIS29 (p = .004), SDMT (p < .001) and MUSIQOL (p = .03) for responders. There were no statistically significant improvements for the non-responders.

CONCLUSIONS

PR Fampridine may have a beneficial effect on information processing speed though not on memory. Study data provide some evidence that fampridine treatment may reduce the impact of MS on daily activities and improve quality of life but has no effect on subjective fatigue and mood.

Genetic diversity of mycobacterium tuberculosis in northern Greece

The aim of the present study was to describe the genetic diversity of Mycobacterium tuberculosis (M.tuberculosis) strains circulating in the region of Northern Greece. A total of thirty-seven M. tuberculosis clinical isolates were analysed by the spoligotyping method. According to the results, six clusters comprising seventeen strains were detected, and the remaining twenty strains showed unique patterns. The M.tuberculosis families according to SITVITWEB were distributed as follows: Haarlem (H) (27.0%); T (24.3%); Beijing (13.5%); Latin-America and Mediterranean (LAM) (5.4%) and S (2.7%). The remaining isolates (27%) did not match any isolates within the database and they were characterized as orphans. Regarding GenoType MTBDRplus results, two strains (5.4%) were Multi-Drug-Resistant, four strains (10.8%), were isoniazid monoresistant, while the remaining thirty-one strains (83.8%) were susceptible. In conclusion, in the region of Macedonia-Thrace (Northern Greece), there was high phylogenetic diversity among M. tuberculosis isolates. Molecular tools used and data presented can have regional and national impact on tuberculosis control.

Coexistence of multiple sclerosis and ankylosing spondylitis: report of two cases

BACKGROUND

Multiple sclerosis (MS) only rarely coexists with ankylosing spondylitis (AS). The optimal management of these patients represents a major challenge.

METHODS

In the present study, we report 2 cases of AS with definite MS comorbidity. One of the AS-MS cases had received anti-TNFα treatment, which was discontinued due to exacerbation of the MS. In addition, we discuss 3 more AS cases with neurological symptoms and atypical white matter demyelinating MRI lesions after anti-TNFα treatment.

DISCUSSION

Given the fact that anti-TNFα drugs can potentially exacerbate a latent MS or induce atypical demyelination in the central nervous system, they should be discouraged or discontinued in relevant cases. The remaining effective therapeutic options for MS are either contradictory for AS (interferon-β), have no definite data regarding their safety/efficacy in AS (glatiramer acetate, azathioprine, natalizumab, fingolimod), or their efficacy in MS-AS is associated with increased treatment risks (rituximab). Any of these proposed treatments may require active patient's informed consent.

Fatal case of extensively drug-resistant Mycobacterium tuberculosis Beijing genotype infection in an injecting drug user, Athens, Greece, 2012

Binary file ES_Abstracts_Final_ECDC.txt matches

Fatal case of extensively drug-resistant Mycobacterium tuberculosis Beijing genotype infection in an injecting drug user, Athens, Greece, 2012

We present the first fatal case of extensively drug-resistant tuberculosis (XDR-TB) in an injecting drug user (IDU) in Athens, Greece, co-infected with human immunodeficiency virus and hepatitis C virus and discuss the implications for public health. Despite immediate initiation of treatment, the patient's condition gradually deteriorated and he died 16 days after hospital admission because of multiple organ failure. The contact tracing investigation revealed no further infections among the patient's contacts.

Impact of the Gen-Probe Amplified MTD® Test on tuberculosis diagnosis in children

OBJECTIVE

To evaluate the performance of the Gen-Probe Amplified MTD® Test (AMTD) for childhood tuberculosis (TB) diagnosis compared to conventional culture.

DESIGN

We retrospectively studied 121 childhood cases (73 males; median age 7 years, range 1-16). Pulmonary samples (104/152, 68%) included gastric aspirates (n = 53), induced sputum samples (n = 43), bronchial aspirates and bronchoalveolar lavage (n = 8). Extra-pulmonary samples (48/152, 32%) included lymph nodes (n = 34) and other sterile fluids (n = 14). Specimens were examined using acid-fast bacilli (AFB) microscopy, AMTD and bacterial culture using BACTEC™ MGIT™ 960 and Löwenstein-Jensen (LJ) media.

RESULTS

A clinical diagnosis of TB was made in 50/121 (41%) children (43/50 pulmonary disease). AFB microscopy was positive in 6%; Mycobacterium tuberculosis was recovered by culture from 16/50 (32%) and AMTD was positive in 29/50 (58%). AMTD sensitivity, specificity, positive predictive value and negative predictive value compared to culture were respectively 100%, 85%, 50% and 100%. For pulmonary vs. extra-pulmonary disease, the performance of AMTD compared to culture was respectively 100%, 77%, 46% and 100% vs. 100%, 97.5%, 75% and 100%.

CONCLUSIONS

Nucleic acid amplification tests are more sensitive and very specific methods for the rapid detection of M. tuberculosis. The AMTD technique increases TB detection in children compared to conventional culture.

Tuberculosis in Greece: bacteriologically confirmed cases and anti-tuberculosis drug resistance, 1995-2009

The Greek National Reference Laboratory for Mycobacteria is a major source of tuberculosis (TB)-related data for Greece, where the TB burden and epidemiology still need to be better defined. We present data regarding newly diagnosed TB cases and resistance to anti-TB drugs during the last 15 years in Greece. Although the total number of newly detected ?? cases has declined, cases among immigrants are increasing. Resistance to first-line anti-TB drugs is widely prevalent, although stable or declining. The implementation of an efficient and effective countrywide TB surveillance system in Greece is urgently needed.

Tuberculosis in Greece: bacteriologically confirmed cases and anti-tuberculosis drug resistance, 1995-2009

The Greek National Reference Laboratory for Mycobacteria is a major source of tuberculosis (TB)-related data for Greece, where the TB burden and epidemiology still need to be better defined. We present data regarding newly diagnosed TB cases and resistance to anti-TB drugs during the last 15 years in Greece. Although the total number of newly detected TB cases has declined, cases among immigrants are increasing. Resistance to first-line anti-TB drugs is widely prevalent, although stable or declining. The implementation of an efficient and effective countrywide TB surveillance system in Greece is urgently needed.

The prevalence of oligoclonal bands in the CSF of patients with primary neurodegenerative dementia

BACKGROUND

Recent guidelines from the United States and Europe on the diagnosis and management of dementia include advice that younger patients with dementia should undergo CSF examination, which frequently includes analysis for oligoclonal bands (OCB). The presence of CNS specific OCB has traditionally been considered suggestive of an inflammatory aetiology, although the interpretation of such a finding in the presence of a normal CSF white cell count and protein is more difficult.

METHODS

We reviewed retrospectively the prevalence of OCB, determined using agarose isoelectric focusing, in a series of 131 well characterised patients with a final diagnosis of a degenerative dementia who had undergone CSF examination.

RESULTS

The mean age of the patients was 60.0 (SD 8.4) years. Seventy (53%) patients had Alzheimer's disease (AD), forty seven (36 %) had frontotemporal lobar degeneration (FTLD), seven (5%) had Dementia with Lewy bodies and the remaining seven (5%) patients had other rarer neurodegenerative dementias. Neuropathological examination had been performed in fifteen (11%) patients. CNS specific OCB were present in nine (7%) patients in this cohort, all of whom had normal CSF white cell counts: four AD patients (a prevalence of 6%), four FTLD patients (a prevalence of 9%), and one patient with Creutzfeldt-Jakob disease (a prevalence of 25%). Investigation of these patients, including two with neuropathologically verified AD and one with post-mortem confirmed CJD, did not reveal an alternative aetiology for their dementia.

CONCLUSION

A central immune response can occur in primary neurodegenerative dementias, albeit uncommonly.

CRD-BP: a c-Myc mRNA stabilizing protein with an oncofetal pattern of expression

The Coding Region Determinant-Binding Protein (CRD-BP) is an RRM and KH-domain-containing protein that recognizes specifically at least three RNAs. It binds to one of the two c-myc mRNA instability elements, to the 5'Un Translated Region (UTR) of the leader 3 IGF-II mRNA and to the oncofetal H19 RNA. CRD-BP has been assigned a role in stabilizing c-myc mRNA by preventing its endonucleolytic cleavage and in repressing the translation of the leader 3 IGF-II mRNA, the major embryonic species of this message. CRD-BP is normally expressed only in fetal tissues. However, its expression is detected in primary tumors and transformed cell lines of different origins. The vast majority of colon (80%) and breast (60%) tumors and sarcomas (73%) express CRD-BP whereas in other tumor types, for example prostate carcinomas, its expression is rare. CRD-BP expression has also been detected in benign tumors such as breast fibroadenomas, meningiomas and other benign mesenchymal tumors, implying a role for this gene in abnormal cell proliferation. In breast carcinomas, CRD-BP expression and or gene copy number gains in the region encompassing the c-myc locus were detected in approximately 75% of tumors, implying that the deregulated expression of c-myc may be more widespread than previously believed. Infiltrated lymph nodes, corresponding to CRD-BP-positive primary tumors, were also found positive indicating that monitoring for CRD-BP could prove useful for the detection and monitoring of disseminated disease.

C-MYC and IGF-II mRNA-binding protein (CRD-BP/IMP-1) in benign and malignant mesenchymal tumors

Mouse coding region determinant-binding (mCRD-BP) and human IGF-II mRNA-binding 1 (hIMP-1) proteins are orthologous mRNA-binding proteins that recognize c-myc and IGF-II mRNA, respectively, and regulate their expression posttranscriptionally. Here, we confirm that human CRD-BP/IMP-1 binds to c-myc mRNA and that it is predominantly expressed in fetal tissues. Moreover, hCRD-BP/IMP-1 expression was detected in cell lines of neoplastic origin and in selected primary tumors. In a series of 33 malignant and 10 benign mesenchymal tumors, 73% and 40%, respectively, were found to express hCRD-BP/IMP-1. In particular, expression was significant in 14 Ewing's sarcomas, all of which were positive. The data suggest that hCRD-BP/IMP-1 plays a role in abnormal cell proliferation in mesenchymal tumors.

Labdane type diterpenes down-regulate the expression of c-Myc protein, but not of Bcl-2, in human leukemia T-cells undergoing apoptosis

Sclareol (1) and ent-3beta-hydroxy-13-epi-manoyl oxide (2) belong to the labdane type diterpenes. They were isolated from the leaves and from the fruits of Cistus creticus subsp. creticus, and were found to be active against human leukemic cell lines. Compound 2 was converted to its thiomidazolide derivative (3). Compounds 1 and 3 were found to induce apoptotic cell death in human T-cell leukemia lines and to interfere with their cell cycle, arresting cells at G(0/1) phase. Apoptosis can involve the activation and/or suppression of critical genes such as c-myc whose reduction or its inappropriate expression can be associated with induction of cell death and bcl-2 whose activation prevents apoptosis in the latter case. In order to detect any concomitant effect (1 and 3) upon c-myc and bcl-2 oncogene expression, we performed Western blot analysis to determine the levels of expression of these two genes upon treatment with the above compounds. Western blot analysis showed that of c-myc proto-oncogene levels were markedly reduced before massive apoptosis ensued in H33AJ-JA1 and MOLT3 cells, while bcl-2 expression remained unaffected. Thus, induction of apoptosis due to compounds 1 and 3 in these T-cell leukemic cell lines is preceded by c-myc down regulation and furthermore sustained bcl-2 expression does not rescue cells from apoptosis under the conditions used.

The polyadenylation inhibitor cordycepin (3'dA) causes a decline in c-MYC mRNA levels without affecting c-MYC protein levels

Study of the distribution of the poly(A) tail length of c-myc mRNA in several cell lines revealed a distinct, prevailing population with short poly(A) tails, derived through sequential deadenylation. To elucidate the possible in vivo function of this distinct short tailed c-myc mRNA population, the polyadenylation inhibitor cordycepin was used. This resulted in a decline in steady state c-myc mRNA levels with the remaining messenger mostly oligoadenylated. However, c-MYC proteins did not follow the reduction of the c-myc mRNA. On the other hand, in cells exposed to physiological agents known to downregulate c-myc expression, the reduction of mRNA steady state levels, was reflected upon c-MYC protein levels. The dissociation between c-myc mRNA and protein levels caused by cordycepin was not due to the stabilization of the c-MYC proteins and was not an indiscriminate effect since in the presence of cordycepin, c-fos mRNA and protein levels concomitantly declined. Our data indicate that under these conditions, a long poly(A) tail is not instrumental for c-myc mRNA translation and furthermore, the discrepancy in the steady state of c-myc mRNA level: c-MYC protein ratio between control cells and cells treated with cordycepin indicates that c-myc mRNA is subjected to translational control.

Comparative total mortality in 25 years in Italian and Greek middle aged rural men

STUDY OBJECTIVE

Mortality over 25 years has been low in the Italian and very low in the Greek cohorts of the Seven Countries Study; factors responsible for this particularity were studied in detail.

PARTICIPANTS AND SETTINGS

1712 Italian and 1215 Greek men, aged 40-59 years, cohorts of the Seven Countries Study, representing over 95% of the populations in designated rural areas.

DESIGN

Entry (1960-61) data included age, systolic blood pressure (SBP), smoking habits, total serum cholesterol, body mass index (BMI), arm circumference, vital capacity (VC), and forced expiratory volume in 3/4 seconds (FEV); the same data were obtained 10 years later. Multivariate Cox analysis was performed with all causes death in 25 years as end point.

MAIN RESULTS

Italian men had higher entry levels of SBP, arm circumference, BMI, and VC; Greek men had higher cholesterol levels, smoking habits, and FEV. Mortality of Italian men was higher throughout; at 25 years cumulative mortality was 48.3% and 35.3% respectively. Coronary heart disease and stroke mortality increased fivefold in Italy and 10-fold in Greece between years 10 and 25. The only risk factor with a significantly higher contribution to mortality in Italian men was cholesterol. However, differences in entry SBP (higher in Italy) and FEV (higher in Greece) accounted for, according to the Lee method, 75% of the differential mortality between the two populations. At 10 years increases in SBP, cholesterol, BMI, and decreases in smoking habits, VC, FEV, and arm circumference had occurred (deltas). SBP increased more and FEV and VC decreased more in Italy than in Greece. Deltas, fed stepwise in the original model for the prediction of 10 to 25 years mortality, were significant for SBP, smoking, arm circumference, and VC in Greece, and for SBP and VC in Italy.

CONCLUSION

Higher mortality in Italian men is related to stronger positive effects of entry SBP and weaker negative (protective) effects of FEV; in addition 10 year increases in SBP are higher and 10 year decreases in FEV are larger in Italy. Unaccounted factors, however, related to, for example, differences in the diet, may also have contributed to the differential mortality of these two Mediterranean populations.

In vivo generation of 3' and 5' truncated species in the process of c-myc mRNA decay

It has been demonstrated that the half-life of c-myc mRNA is modulated in response to physiological agents. The elucidation of the decay process and the identification of the critical steps in the in vivo c-myc mRNA degradation pathway can be approached by following the fate of c-myc mRNA under the influence of such factors. IFN-alpha was the factor used to modulate c-myc mRNA half-life in HeLa 1C5 cells, a stable clone derived from HeLa cells. This cell line carries multiple copies of the c-myc gene, under the control of the dexamethasone inducible mouse mammary tumor virus-long terminal repeat (MMTV-LTR). Exposure of HeLa 1C5 cells to IFN-alpha resulted in a further 2-fold increase over the dexamethasone-induced c-myc mRNA. However, the c-myc mRNA in IFN-alpha treated cells was less stable than that in the control cells. RNase H mapping of the 3' untranslated region of c-myc mRNA revealed, in addition to the full length mRNA, three smaller fragments. These fragments were proven to be truncated, non-adenylated c-myc mRNA species generated in vivo. Exposure of HeLa 1C5 cells to Interferon-alpha before induction with dexamethasone resulted in the enhanced presence of these intermediates. RNase H analysis of c-myc mRNA after actinomycin D chase revealed that deadenylation led to the formation of a relatively more stable oligoadenylated c-myc mRNA population which did not appear to be precursor to the truncated intermediates. The detection of truncated 3' end c-myc mRNA adenylated fragments as well, implies that the c-myc mRNA degradation process may follow an alternative pathway possibly involving endonucleolytic cleavage.

Synthesis of some 3',5'-dideoxy-5'-C-phosphonomethyl nucleosides

Ammonium [1-(3',5',6'-trideoxy-beta-D-erythro-hexofuranosyl)thymine]-6'- phosphonate (1), ammonium 3',5'-dideoxycytidine-5'-C-methylphosphonate (2) and 3',5'-dideoxyadenosine-5'-C-methyl phosphonic acid (3) have been synthesized and tested for anti-HIV activity. The key steps involved an Arbuzov reaction between triethyl phosphite and 3,5,6-trideoxy-6-iodo-1,2-O-isopropylidene-alpha-D-erythro- hexofuranose (7), followed by condensation with the appropriate nucleoside bases. The substances 1, 2 and 3 have been tested in vitro against HIV.