Biomedical subjects

M Bucci

Publications and source records attributed to M Bucci.

At least 55 records · Page 3Linked to original sources

PubMed1998

Association of human papillomavirus type 11 with carcinoma of the penis.

Human papillomaviruses (HPVs) are epithelium-tropic viruses associated with several cutaneous, epithelial, and mucosal lesions. The oncogenic potential varies considerably among the more than 70 different genotypes so far identified. HPV 6 and 11 are generally found in benign genital condilomata or laryngeal papillomas, but they have been sporadically associated with genital malignancies. Polymerase chain reaction (PCR) primed by degenerated consensus oligonucleotides (from a late region of the HPV genome) allows one to amplify a broad spectrum of HPV, whereas the amplification with specific primers is restricted to a limited number of HPVs. Therefore, the restriction fragment length polymorphism assay permits one to identify the HPV type present in the PCR product. We report a case of an invasive verrucous carcinoma of the penis associated with HPV 11, a type previously considered noncarcinogenic.

Carcinoma, Verrucous↗

PubMed1998

The detection of human papillomavirus DNA in skin tags.

Human papillomavirus (HPV) is associated with benign cutaneous or mucosal lesions and with malignant tumours, but none of the HPV types has so far been related to skin tags. Skin biopsy specimens from 49 Caucasian patients suffering from the presence of multiple soft fibromas were analysed by means of dot blot hybridization and by polymerase chain reaction assays aimed at detecting all known HPV types. The results revealed the presence of HPV DNA type 6/11 in 88% of the skin tags examined. This result supports the hypothesis that HPV plays a part in the progression of cutaneous soft fibromas, as previously reported for laryngeal papillomas.

Adult↗

PubMed1998

A novel fluorescence-based genetic strategy identifies mutants of Saccharomyces cerevisiae defective for nuclear pore complex assembly.

Nuclear pore complexes (NPCs) are large proteinaceous portals for exchanging macromolecules between the nucleus and the cytoplasm. Revealing how this transport apparatus is assembled will be critical for understanding the nuclear transport mechanism. To address this issue and to identify factors that regulate NPC formation and dynamics, a novel fluorescence-based strategy was used. This approach is based on the functional tagging of NPC proteins with the green fluorescent protein (GFP), and the hypothesis that NPC assembly mutants will have distinct GFP-NPC signals as compared with wild-type (wt) cells. By fluorescence-activated cell sorting for cells with low GFP signal from a population of mutagenized cells expressing GFP-Nup49p, three complementation groups were identified: two correspond to mutant nup120 and gle2 alleles that result in clusters of NPCs. Interestingly, a third group was a novel temperature-sensitive allele of nup57. The lowered GFP-Nup49p incorporation in the nup57-E17 cells resulted in a decreased fluorescence level, which was due in part to a sharply diminished interaction between the carboxy-terminal truncated nup57pE17 and wt Nup49p. Interestingly, the nup57-E17 mutant also affected the incorporation of a specific subset of other nucleoporins into the NPC. Decreased levels of NPC-associated Nsp1p and Nup116p were observed. In contrast, the localizations of Nic96p, Nup82p, Nup159p, Nup145p, and Pom152p were not markedly diminished. Coincidentally, nuclear import capacity was inhibited. Taken together, the identification of such mutants with specific perturbations of NPC structure validates this fluorescence-based strategy as a powerful approach for providing insight into the mechanism of NPC biogenesis.

Alleles↗

PubMed1998

Treatment of severe intermittent claudication with PGE1--a short-term vs a long-term infusion plan--a 20 week, European randomized trial--analysis of efficacy and costs.

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe intermittent claudication was studied by comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 109 patients (96 completed the study) with an average total walking distance of 65.5 +/- 8 m (range 20-109). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 microg PGE1, 5 days each week for 4 weeks). In phase 3 (4-week interval period) PGE1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP, phase 2 treatment was performed in 2 days by a 2-hour infusion (1st day: morning 20 microg, afternoon 40 microg; 2nd day morning and afternoon 60 microg). The reduced dosage was used only at the first cycle (week 0) to evaluate reduced tolerability or side effects. Full dosage (60 microg b.i.d.) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of the 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks (101.5% in STP vs 78.3% in LTP), at 8 weeks (260.9% STP vs 107.3% LTP), and at 20 weeks (351% STP vs 242% LTP). Comparable increases in pain-free walking distance were observed in the two groups. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 7% of the treated subjects in the LTP and 5% in the STP. Average cost of LTP was approximately 6,588 ECU; for STP the average cost was approximately 1,881 ECU. The cost to achieve an improvement in walking distance of 1 m was 35.6 ECU with the LTP and 9.45 ECU with the STP (26% of the LTP cost; p<0.02). For an average 100% increase in walking distance the LTP cost was 1,937 ECU vs 550 ECU with STP (p<0.02). The cost of PGE1 (including infusion and operative costs) was 25% of the total cost for LTP (24.9% for STP). In summary, between-group-analysis favors STP, in terms of walking distance and costs. Results indicate good efficacy and tolerability of PGE1 treatment. With STP less time is spent in infusion and more can be spent in the exercise program. STP reduces costs, speeds up rehabilitation, and may be used in a larger number of nonspecialized units available to follow the protocol.

Alprostadil↗

PubMed1998

[Analysis of costs and results of prostaglandin (PGE1 alpha-cyclodestrin) therapy of peripheral arterial diseases].

BACKGROUND: In this study patients with peripheral vascular disease were treated with PGE1 alpha-ciclodestrina. In the intermittent claudication group (walking distance at inclusion between 200-600 m) we included 55 patients treated with PGE1 alpha-ciclodestrina (15 diabetics) and 22 controls (not treated with PGE1 alpha-ciclodestrina). In the critical ischemia group 46 patients were treated and 47 patients followed up as controls (rest pain or necrotic lesions had been present for more than 2 weeks). METHODS: Patients with intermittent claudication were evaluated by a treadmill test (walking distance was the endpoint) and in those with critical ischemia the number of minor and major amputations in 12 months were considered as endpoints. A dose of PGE1 alpha-ciclodestrina (60-80 micrograms/day for 2 days) was repeated either every 6 or, in alternative, every 10 weeks. In the control group only antiplatelet agents, support treatment (control of risk factors) and exercise were used. RESULTS: All subgroups of patients treated with PGE1 alpha-ciclodestrina with intermittent claudication increased their walking distance (including the subgroup of diabetics). In critical ischemia there were no major amputations (only 2 minor amputations) in the PGE1 alpha-ciclodestrina group vs 10.6% (of major amputations) in the control group. Also an evaluation of laser Doppler flow, volume flow and transcutaneous PO2 indicated in subgroups of patients an improvement of microcirculation and limb perfusion with PGE1 alpha-ciclodestrina. CONCLUSIONS: The cost analysis and the quality of life evaluation indicated a benefit of preserving limbs from amputation.

Alprostadil↗

PubMed1998

[European trial of PGE1 alpha cyclodextrin. Short-term vs. long-term therapy in intermittent claudication].

BACKGROUND: The efficacy, safety and cost of prostaglandin E1 (PGE1 alpha-ciclodestrina) in the treatment of severe intermittent claudication was studied comparing a long term treatment protocol (LTP) with a short term treatment protocol (STP) in a randomised, 20-week study. METHODS: The study has selected 120 patients (109 were included and 99 completed the study). The average total walking distance at inclusion was 65.5 +/- 8 m (range 20-109). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP phase 2 was the main treatment phase. The treatment was performed with 2-hour infusions (60 micrograms PGE1 alpha-ciclodestrina, 5 days each week for 4 weeks. In phase 3 (4-week interval period) PGE1 alpha-ciclodestrina was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP phase 2 treatment was performed in two days with a 2-hour infusion (1st day: morning 20 micrograms, afternoon 40 micrograms; 2nd day 60 micrograms, morning and afternoon). The reduced dosage was used only at the first cycle to evaluate reduced tolerability or side effects. Full dosage (60 micrograms b.i.d.) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, 12 (phase 3). The observation period was between weeks 12 and 20 (phase 4). For both protocols a treadmill test was performed at inclusion, at the beginning of each phase and at the end of 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors plan was used in both groups. RESULTS: Intention-to-treat analysis indicated an increase in walking distance which improved at 4 weeks (101.5% in STP vs 78.3% in LTP), at 8 weeks (260.9% in STP vs 107.3% in LTP) and at 20 weeks (351% in STP vs 242% in LTP). Comparable increases in pain-free walking distance were observed in the two groups. No serious drug-related side effects were observed. Local, mild, adverse reactions were seen in 7% of the treated subjects in the LTP and 5% in the STP. The average cost of LTP was approximately 6.588 ECU; for STP the average costs was approximately 1881 ECU. The cost to achieve an improvement in walking distance of 1 m was 35.6 ECU with the LTP and 9.45 ECU with the STP (26% of the LTP cost; P < 0.02). For an average 100% increase in walking distance LTP cost was 1937 ECU vs 550 ECU with STP (P < 0.02). The cost of PGE1 alpha-ciclodestrina (including infusion and operative costs) was 25% of the total cost for LTP (24.9% for STP). CONCLUSION: In summary between-group-analysis favours STP considering walking distance and costs. Results indicate good efficacy and tolerability of PGE1 alpha-ciclodestrina treatment. With STP less time is spent in infusion and more can be spent in the exercise program. STP reduces costs, speeds up rehabilitation and may be used in a larger number of non-specialised units available to follow the protocol.

Alprostadil↗

PubMed1998

[Reduction of cardiovascular morbidity/mortality in arteriopathies treated ith PGE1 alpha-cyclodextrin].

BACKGROUND: Cardiovascular morbidity and mortality were evaluated in two groups of vascular patients (one treated with PGE1 alpha-ciclodestrina according to the short term protocol and one reference group) with a follow up of at least 24 month. METHODS: The former group included patients who had been treated with at least four PGE1 alpha-ciclodestrina, short-term treatment cycles per year while the latter was a historical reference group managed without prostaglandins. The two groups were comparable for sex and age distribution. RESULTS: In the PGE1 alpha-ciclodestrina group 142 patients (mean age 64 +/- 17; M:F = 84:58) had been treated (47 for intermittent claudication and 95 for critical ischemia: 43 for rest pain, and 52 for localised gangrene). The historical reference group included 157 patients (mean age 65 +/- 18: M:F = 91:66); 53 with intermittent claudication and 104 with critical ischemia (49 rest pain, 55 gangrene). In claudicants yearly cardiovascular morbidity was reduced from the 15% observed in the reference group to 10% in patients treated with PGE1 alpha-ciclodestrina. Yearly mortality decreased from 11% in the reference group to 6% in the treated group. In rest pain patients morbidity decreased from 24% in the reference group to 19% in the treated group. Mortality also decreased (from 16% to 11%). In patients with gangrene the difference in morbidity between the reference group (35%) and the PGE1 alpha-ciclodestrina group (27%) was even more evident (P < 0.025). In this group the mortality per year was reduced from 26% in the reference group to 17% in the PGE1 alpha-ciclodestrina treated group. CONCLUSION: It appears that cyclic treatment with PGE1 alpha-ciclodestrina produces not only an improvement in signs and symptoms related to vascular disease but also an important decrease in cardiovascular morbidity and mortality which has not been previously reported.

Age Distribution↗

PubMed1998

[Cardiovascular morbidity/mortality modified by the use of FGE1 alpha-cyclodextran and calcium heparin in patients with severe vascular diseases].

BACKGROUND: Morbidity and mortality were evaluated in three groups of vascular patients: one group was treated with PGE1 alpha-ciclodestrina according to the short term protocol; the second group was treated with PGE1 alpha-ciclodestrina and subcutaneous calcium heparin (SCH; 0.5 ml once daily, in the evening) while a third group was a historical reference group. METHODS: All included patients had a follow up of at least 12 months. The historical reference group had been managed without PGE1 alpha-ciclodestrina or SCH while in the two PGE1 alpha-ciclodestrina groups included patients who had been treated with at least four PGE1 alpha-ciclodestrina short-term treatment cycles per year. The 3 groups were comparable for sex and age distribution. In the PGE1 alpha-ciclodestrina group 142 patients (64 +/- 17; M:F = 84:58) had been treated (47 for intermittent claudication and 95 for critical ischemia). The historical reference group included 157 patients (65 +/- 18: M:F = 91:66); 53 with intermittent claudication and 104 with critical ischemia). The group treated with PGE1 alpha-ciclodestrina and SCH included 74 patients (27 with claudication and 47 with critical ischemia). RESULTS: In claudicants yearly cardiovascular morbidity was reduced from 15.5% in the reference group to 10.2% in patients treated with PGE1 alpha-ciclodestrina and to 7.9% in those treated with PGE1 alpha-ciclodestrina and SCH. Mortality decreased from 11.3% in the reference group to 6% in the PGE1 alpha-ciclodestrina group and to 5.1% in the PGE1 alpha-ciclodestrina + SCH group. In patients with critical limb ischemia morbidity decreased from 28.6% in the reference group to 23.2% in PGE1 alpha-ciclodestrina-group and to 19.4% in the PGE1 alpha-ciclodestrina + SCH group. Mortality also decreased from 16% (reference group) to 13% in the PGE1 alpha-ciclodestrinagroup, to 10.3% in the PGE1 alpha-ciclodestrina + SCH group. CONCLUSION: Cyclic treatment with PGE1 alpha-ciclodestrina produces an important decrease in cardiovascular morbidity and mortality which could be further reduced by the chronic use of subcutaneous calcium heparin.

Aged↗

PubMed1998

Identification of an alternative open reading frame ("hidden gene"?) stringently required for infectivity of poliovirus cDNA clones.

Translation of the uncapped poliovirus RNA starts at the AUG triplet spanning positions 741-743, and proceeds uninterrupted for almost the entire length of the genome. Such a cap-independent mechanism of internal initiation of translation determines that a long, extra-cistronic region extends between the 5'-end and the main open reading frame (ORF). We have identified 10 short ORFs initiated by the alternative translation initiation codons ACG, AUA, and GUG in the 5'-terminal extra-cistronic region (5'-ECR) of poliovirus RNA. Mutations introduced in all but one of these mini-cistrons had no effect on the infectivity of full-length cDNA clones, except when they modified a "hidden frame" spanning between nucleotides 157-192 (starting triplet: ACG). The mini cistron 157-192 is conserved in position, length and sequence in the genome of all types and strains of poliovirus. Adaptation to rat (Lansing) or mouse (variant of Sabin 2) is accompanied by a consistent pattern of changes in the primary sequence of this "hidden frame". The substitutions that abrogated the infectivity of cDNA clones were not expected to modify the predicted secondary structure of the 5'-ECR, and they did not alter the ability of the IRES to direct internal initiation of translation in bi-cistronic mRNAs. The infectivity of the mutated poliovirus cDNAs could be complemented in trans by co-transfecting the target COS-1 cells with an expression vector containing just the 5'-ECR of poliovirus type 2 (Lansing strain). The infectivity of poliovirus cDNA could be restored by co-transfecting short RNA transcripts of the wt 5'-ECR (Lansing), suggesting that the complementation in trans indeed requires the expression of the helper cDNA clone.

Animals↗

PubMed1998

Increased infectivity of hepatitis A virus cDNA clones with engineered 5'-terminal extra-cistronic sequences.

The genomic RNA of Hepatitis A virus (HAV), a picornavirus of the hepatovirus group, is a single-stranded molecule, ca. 7.5 kb in length of positive polarity. Translation of this uncapped RNA starts at the 10th (or 11th) AUG triplet (position 734-36), by a mechanism of internal initiation of translation. The long sequences extending between the uncapped 5'-end and the translation initiation site contain two (instead of just one) pyrimidine-rich tracts (PRTs) spanning nucleotides 94-140 and 711-724, respectively. The latter lies only 11 nucleotides upstream from the initiation site of translation, and the question arose as to whether the notoriously poor replication ability of HAV was a consequence of a down regulation of translation due to the too short "spacer" sequence intervening between the 3'-PRT and the initiation of the main open reading frame. To address this issue, a series of full-length HAV cDNA clones were constructed in which the "spacer" sequence (normally 11 nts) was brought to 45 nts. Following transfection of COS-1 cells with these constructs, the amount of HAV (+)-strand RNA was determined by dot hybridization using a strand-specific RNA probe. HAV cDNA clones carrying a 45-nt "spacer" increased two-fold the rate of (+)-strand viral RNA synthesis, suggesting that the poor translation ability of HAV RNA may be one of the mechanisms responsible for the lengthy replication cycle of HAV.

Animals↗

PubMed1997

Factor Xa as an interface between coagulation and inflammation. Molecular mimicry of factor Xa association with effector cell protease receptor-1 induces acute inflammation in vivo.

Coagulation proteases were tested in a rat model of acute inflammation. Subplantar injection of Factor Xa (10-30 microg) produced a time- and dose-dependent edema in the rat paw, and potentiated carrageenin-induced edema. In contrast, the homologous protease Factor IXa was ineffective. This inflammatory response was recapitulated by the Factor Xa sequence L83FTRKL88(G), which mediates ligand binding to effector cell protease receptor-1 (EPR-1), while a control scrambled peptide did not induce edema in vivo. Conversely, injection of the EPR-1-derived peptide S123PGKPGNQNSKNEPP137 (corresponding to the receptor binding site for Factor Xa) inhibited carrageenin-induced rat paw edema, while the adjacent EPR-1 sequence P136PKKRERERSSHCYP150 was without effect. EPR-1-Factor Xa-induced inflammation was characterized by fast onset and prominent perivascular accumulation of activated and degranulated mast cells, was inhibited by the histamine/serotonin antagonists cyproheptadine and methysergide, but was unaffected by the thrombin-specific inhibitor, Hirulog. These findings suggest that through its interaction with EPR-1, Factor Xa may function as a mediator of acute inflammation in vivo. This pathway may amplify both coagulation and inflammatory cascades, thus contributing to the pathogenesis of tissue injury in vivo.

Amino Acid Sequence↗

PubMed1997

In vivo dynamics of nuclear pore complexes in yeast.

While much is known about the role of nuclear pore complexes (NPCs) in nucleocytoplasmic transport, the mechanism of NPC assembly into pores formed through the double lipid bilayer of the nuclear envelope is not well defined. To investigate the dynamics of NPCs, we developed a live-cell assay in the yeast Saccharomyces cerevisiae. The nucleoporin Nup49p was fused to the green fluorescent protein (GFP) of Aequorea victoria and expressed in nup49 null haploid yeast cells. When the GFP-Nup49p donor cell was mated with a recipient cell harboring only unlabeled Nup49p, the nuclei fused as a consequence of the normal mating process. By monitoring the distribution of the GFP-Nup49p, we could assess whether NPCs were able to move from the donor section of the nuclear envelope to that of the recipient nucleus. We observed that fluorescent NPCs moved and encircled the entire nucleus within 25 min after fusion. When assays were done in mutant kar1-1 strains, where nuclear fusion does not occur, GFP-Nup49p appearance in the recipient nucleus occurred at a very slow rate, presumably due to new NPC biogenesis or to exchange of GFP-Nup49p into existing recipient NPCs. Interestingly, in a number of existing mutant strains, NPCs are clustered together at permissive growth temperatures. This has been explained with two different hypotheses: by movement of NPCs through the double nuclear membranes with subsequent clustering at a central location; or, alternatively, by assembly of all NPCs at a central location (such as the spindle pole body) with NPCs in mutant cells unable to move away from this point. Using the GFP-Nup49p system with a mutant in the NPC-associated factor Gle2p that exhibits formation of NPC clusters only at 37 degrees C, it was possible to distinguish between these two models for NPC dynamics. GFP-Nup49p-labeled NPCs, assembled at 23 degrees C, moved into clusters when the cells were shifted to growth at 37 degrees C. These results indicate that NPCs can move through the double nuclear membranes and, moreover, can do so to form NPC clusters in mutant strains. Such clusters may result by releasing NPCs from a nuclear tether, or by disappearance of a protein that normally prevents pore aggregation. This system represents a novel approach for identifying regulators of NPC assembly and movement in the future.

Biological Transport↗

PubMed1997

Defining the essential functional regions of the nucleoporin Nup145p.

Studies of the essential nucleoporin Nup145p have shown that its depletion is coincident with a block in RNA export and that deletion of its amino-terminal domain results in clustering of nuclear pore complexes. To further define the functional domains of Nup145p, we have characterized a panel of nup145 mutants. Deletions from both the amino terminus and the carboxy terminus resulted in temperature sensitive mutants that accumulated polyadenylated RNA in the nucleus at the non-permissive temperature. In addition, these mutants also displayed constitutive clustering of nuclear pore complexes in localized patches of the nuclear envelope. These results suggested that an internal region of Nup145p consisting of amino acids 593-893 is essential for function. Accordingly, when this region was deleted, growth was not supported at any temperature, whereas the region alone was able to complement a null mutation when expressed on a high copy plasmid. Previous studies have suggested that Nup145p is cleaved into two polypeptides of approximately 65 and 80 kDa. Interestingly, our experiments suggest that cleavage occurs in vivo. However, a small internal deletion of 17 amino acid residues that abolished cleavage had no effect on cell growth. Therefore, cleavage is not necessary for Nup145p function. When a sequence harboring the Nup145p cleavage site required for Nup145p cleavage was inserted in a chimeric protein, it was not sufficient for mediating cleavage. Cleavage likely requires a second region from amino acid residues 247-524 in addition to the cleavage site.

Fungal Proteins↗

PubMed1996

The synovial-like membrane at the bone interface in loose total hip replacements contains high levels of extracellular group II phospholipase A2.

Progressive lysis of bone in loose total hip replacement has been ascribed to the capacity of the synovial-like membrane present at the bone interface to produce prostaglandin E2 and cytokines such as tumor necrosis factor (TNF alpha). Phospholipase A2 (PLA2) produces rate limiting precursor i.e. arachidonic acid in the biosynthesis of various types of biologically active lipids including prostaglandins. It has been shown that extracellular human group II phospholipase A2 is present in large amount in synovial fluid of patients with synovitis and that the expression of this enzyme is under the control of cytokines such as TNF alpha. Furthermore, the human extracellular enzyme has been also shown to induce in an experimental animal model to cause disruption of a synovial like membrane without increasing prostaglandin production. Here we have evaluated PLA2 and TNF alpha levels in the supernatant of homogenate of the synovial-like membrane present at the bone interface retrieved from six patients with a loose non septic failed total hip replacement. In all the membranes examined were found high levels of both TNF alpha (856 +/- 211 units/ml) and extracellular phospholipase A2 (2616 +/- 862 ng/ml). These findings suggest that extracellular PLA2 may play a major role in the process that cause disruption of the membrane at the bone-prosthesis interface.

Bone and Bones↗

PubMed1996

A foodborne outbreak of gastroenteritis involving Listeria monocytogenes.

An outbreak of gastroenteritis occurred in Italy among 39 persons who had attended a private supper. All guests were previously healthy, young, non-pregnant adults; 18 (46%) had symptoms, mostly gastrointestinal (78%), with a short incubation period. Four were hospitalized with acute febrile gastroenteritis, two of whom had blood cultures positive for Listeria monocytogenes. No other microorganisms were recovered from the hospitalized patients' specimens. Epidemiological investigation identified rice salad as the most likely vehicle of the food-borne outbreak. L. monocytogenes was isolated from three leftover foods, the kitchen freezer and blender. Isolates from the patients, the foods and the freezer were indistinguishable: serotype 1/2b, same phage type and multilocus enzyme electrophoretic type. Eight (36%) of 22 guests tested were found to have antibodies against L. monocytogenes, compared with none of 11 controls from the general population. This point source outbreak was probably caused by infection with L. monocytogenes. Unusual features included the high attack rate among immunocompetent adults and the predominance of gastrointestinal symptoms.

Adolescent↗

PubMed1996

[Keratoacanthoma centrifugum marginatum. Possible etiological role of papillomavirus and therapeutic response to etretinate].

INTRODUCTION: Keratoacanthoma centrifugum marginatum is an uncommon keratoacanthoma of unknown etiology. We report a case suggesting a possible etiological role for a papillomavirus. Etretinate was an effective treatment. CASE REPORT: A 65-year-old woman had keratoacanthoma centrifugum marginatum of the antero-inferior aspect of the lower third of the right leg for 5 years. Fifteen years earlier, an infection had occurred at the same site after a trauma and was treated by oral antibiotics. Surgical exeresis was difficult due to the wide spread of the lesion. Etretinate given at an initial dose of 1 mg/kg/d for 6 weeks then reduced by half for 2 months led to nearly complete cure. DISCUSSION: Keratoacanthoma centrifugum marginatum, verrucous carcinoma and epidermal carcinoma have some histological characteristics in common, suggesting a possible common etiological agent which could be certain strains of the human papillomavirus (HPV). In our case etretinate provided cure, possibly due to its antitumoral activity and perhaps due to its antiviral activity. The presence of koilocytes suggested HPV infection which was confirmed by PCR. This test does not however provide proof of the etiological role of HPV. We are currently studying the presence of HPV in keratoacanthomas and their possible etiological role.

Aged↗

PubMed1995

Mutational analysis of the 3'-terminal extra-cistronic region of poliovirus RNA: secondary structure is not the only requirement for minus strand RNA replication.

A series of mutations were introduced in the 3'-terminal untranslated region (3'-UTR) of full-length infectious poliovirus cDNA clones, and following transfection of COS-1 cells the ability of these constructs to generate viable viral particles and/or to support viral RNA synthesis was assayed. Substitution of the 3'-UTR of poliovirus RNA with the equivalent sequences of HAV RNA abrogated viral RNA replication, whereas the introduction of extended 'foreign' sequences between the open reading frame and the 3'-UTR was well tolerated. Point mutation that either destabilized the stem-and-loop structure or altered the sequence of the loop in domain 'Y' (nomenclature as per Pilipenko et al., [Nuclei Acids Res. 20 (1992) 1739-1745]) abolished both the infectivity and viral RNA synthesis. These were not restored by compensatory mutation that reconstructed the native secondary structure of this domain, suggesting that the secondary/tertiary folding of the 3'-UTR is not the only determinant for template recognition at initiation of RNA synthesis, but rather that a specific primary sequence is indeed required.

Animals↗

PubMed1995

Alkaline phosphatase distribution in the plasma membrane of uterine epithelial cells is markedly altered during early pregnancy in the rat.

Ultrastructural and light microscopic cytochemical methods were used to study the distribution and changes in distribution of alkaline phosphatase in the apical plasma membrane of rat uterine epithelial cells during different stages of early pregnancy up to the time of attachment of the blastocyst. Reaction product generated by alkaline phosphatase (AP) was located along the apical plasma membrane at each stage investigated. However, a very different organization of reaction product was observed depending on the time during early pregnancy with a continuous pattern appearing all along the microvilli on day 1. This pattern was subsequently converted into a clumped and highly 'patchy' appearance around the time of blastocyst attachment by day 6 of pregnancy. This change in pattern and distribution was only seen on the luminal epithelial cells with glandular epithelial cells and blood vessels displaying an unchanging distribution.

Alkaline Phosphatase↗