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M Mikkonen

Publications and source records attributed to M Mikkonen.

15 recordsLinked to original sources
PubMed1996

The early gene region completes the nucleotide sequence of Lactobacillus delbrueckii subsp. lactis phage LL-H.

Transcription of genes from phage LL-H can be divided into an early phase and a late phase. The early gene region was located in a 5.9-kb segment of the phage LL-H genome and it was part of the sequence that completed the phage LL-H genome sequence, 34 659 bp in size. Phage LL-H is the first completely sequenced Lactobacillus phage. In the main coding strand of phage LL-H genome 48 putative ORFs could be detected, but only four small putative ORFs could be found in the opposite strand. The ORFs covered 85.6% of the main coding strand. Function could be assigned to eleven of the phage LL-H ORFs either by biochemical analyses or by database homologies. A single-strand-binding protein, SSB, was detected in addition to the previously determined functions (small and large subunits of terminase, intron-encoded endonuclease, six structural proteins, phage lysin). For 15 additional ORFs of phage LL-H homology was detected in databases, but no function could be inferred for them.

Bacteriophages↗
PubMed1996

Defective site-specific integration elements are present in the genome of virulent bacteriophage LL-H of Lactobacillus delbrueckii.

The phage attachment site, attP, and the integrase-encoding gene, int, are sufficient to promote site-specific integration of the temperate phage mv4 genome into the chromosome of the Lactobacillus delbrueckii host (L. Dupont, B. Boizet-Bonhoure, M. Coddeville, F. Auvray, and P. Ritzenthaler, J. Bacteriol. 177:586--595, 1995). The mv4 genome region containing these elements was compared at the nucleotide and amino acid levels with that of the closely related virulent phage LL-H. Complex DNA rearrangements were identified; a truncated integrase gene and two sites homologous to the mv4 attP site were detected in the genome of the virulent phage LL-H. These observations suggest that the two phages derive from a common temperate ancestor.

Amino Acid Sequence↗
PubMed1995

A group I intron in the terminase gene of Lactobacillus delbrueckii subsp. lactis phage LL-H.

An 837 nt long group IA intron was discovered in the Lactobacillus delbrueckii subsp. lactis virulent phage LL-H genome. The LL-H intron conforms well to the secondary structure that is common to all group I introns. The only exception is that the extreme 3' nucleotide of the intron is an A residue instead of the usual G; despite this the intron is efficiently spliced in vivo. This LL-H intron contains an ORF, ORF168, which shows homology with endonucleases encoded by ORFs contained in Bacillus subtilis phage introns. At present, the LL-H intron is the only one found in the phages of lactic acid bacteria and the first one to be found in a phage belonging to the most abundant taxonomic group, group B or Siphoviridae. The LL-H intron interrupts gene terL, the product of which (50.5 kDa, TerL) is significantly homologous to the large subunit of B. subtilis phage SPP1 terminase. The product of the upstream gene, terS of LL-H (15.9 kDa, TerS), shows homology to small subunits of B. subtilis phage terminases.

Amino Acid Sequence↗
PubMed1994

Characterization of the genome region encoding structural proteins of Lactobacillus delbrueckii subsp. lactis bacteriophage LL-H.

Two regions from the genome of the virulent Lactobacillus delbrueckii subsp. lactic bacteriophage LL-H were sequenced (2330 and 12939 bp; 44% of the 34.6-kb genome). Together with the previously sequenced region containing the major capsid protein-encoding gene (2498 bp), the sequence had 21 open reading frames (ORFs) on the main coding strand. Only two putative ORFs were detected on the complementary strand. The ORFs covered 93.2% of the sequence. All but four of the ORFs were preceded by a ribosome-binding site. Only four longer non-coding stretches of sequences (175-278 nucleotides (nt) in size) were present. The longest of the non-coding regions contained an A + T-rich sequence that is surrounded by eight perfect copies of an 8-nt sequence that is present both as direct and inverted repeats. This region could represent the origin of replication. All the previously mapped structural protein-encoding genes of phage LL-H were included in the sequence. Genes were identified for the following five proteins: gp19 (encoded by gene g17), gp58 (g71), gp61 (g57), gp75 (g70) and gp89 (g88). N-terminal amino-acid sequencing was performed on gp19 and gp75, and it was found that the N-terminal Met had been post-translationally removed from both proteins.

Bacteriophages↗
PubMed1994

Ribosome binding site consensus sequence of Lactobacillus delbrueckii subsp. lactis bacteriophage LL-H.

The putative ribosome binding sites preceding 32 of Lactobacillus delbrueckii subsp. lactis bacteriophage LL-H genes were compared. A highly conserved consensus sequence for the ribosome binding sites of LL-H genes was inferred, GAAAGGAG. This study included the characterization of the last nucleotides of the 3'-end of the 16S rRNA molecule from L. delbrueckii subsp. lactis and its comparison to the ribosome binding site consensus sequence.

Bacteriophages↗
PubMed1984

Prevalence of oral mucosal lesions associated with wearing removable dentures in Finnish adults.

Of a representative sample of 8000 persons aged 30 and over living in Finland, 3875 users of removable dentures were examined. The condition of the oral mucosa was recorded during clinical examinations. The prevalence of oral mucosal lesions associated with removable dentures was analyzed according to age, sex, place of residence, geographical region of living, and type and location of prosthesis. Lesions were found in about 50% of the denture wearers. Women were affected more often than men. The prevalence of lesions decreased with age and differed slightly according to region of living and place of residence. Compared with the wearing of partial dentures, wearing complete dentures increased the risk of lesions. Only one of the 72 denture users who wore a denture with metallic base plate had oral mucosal lesions associated with wearing a denture.

Adult↗
PubMed1984

Oral hygiene, dental visits and age of denture for prevalence of denture stomatitis.

A representative sample of Finnish denture wearers (n = 3875) aged 30 or over were examined clinically and interviewed about their oral hygiene habits, use of dental services and possible prosthetic treatment during last visit to a dentist. Of these denture wearers, over 80% brushed their dentures at least once a day, and 16% visited a dentist at least once in 2 yr. For denture stomatitis the age-standardized risk ratio decreased with brushing frequency in women and increased in men. For frequency of dental visits the prevalence of denture stomatitis increased in both men and women when visits were made over 2-yr intervals. The prevalence of denture stomatitis was higher in the group with dentures over 1 yr old. It seems that the oral hygiene measures as they are generally carried out and regular dental visits are not effective enough methods in preventing denture stomatitis.

Adult↗
PubMed1983

Clinical and radiologic re-examination of apicoectomized teeth.

Healing after periapical surgery was studied clinically and radiologically in 108 patients in whom apicoectomy had been performed on 174 teeth. Histologic diagnosis was used to determine healing results; teeth with periapical granuloma tend to heal less successfully than teeth showing inflammation or cysts. Postoperative treatment played an important role in the healing process. In making a prognosis one must include preoperative status (including periodontal status), operating method, and postoperative treatment. The age of the patient also has some influence on healing.

Adolescent↗
PubMed1982

Screening of asymptomatic postmenopausal women for gynecological malignancies, with special reference to endometrial sampling methods.

To investigate the applicability of cytological and histological endometrial sampling methods and to study the incidence of silent premalignant or malignant gynecological diseases during the postmenopausal years, 415 asymptomatic women were examined both clinically and with cytological smears and 360 of them also examined with jet wash or pistolet aspiration and Vabra curettage. Examination with jet wash, pistolet aspiration and Vabra curettage was possible in 57.2%, 83.1% and 76.1% of the cases, respectively. The cytological specimens (jet wash, pistolet) and the Vabra curettage specimens were inadequate in 3.7% and 44.5% of cases, respectively. Our study revealed two malignant (one mammary and one gastric cancer with ovarian metastases), seven premalignant (four endometrial and three cervical) and 55 benign gynecological or mammary lesions, amounting to 15.4% of the 415 women. These results, with only four severe endometrial lesions, indicate the restriction of endometrial screening examinations to only well-defined high risk women. Of the methods used, the pistolet aspiration is the most recommendable due to its applicability, patient acceptance, diagnostic reliability and the low incidence of unsatisfactory samples.

Adult↗
PubMed1982

Prevalence of different morphologic forms of the human tongue in young Finns.

Morphologic variations on the surface of the human tongue were examined in 381 patients divided by age into three groups (Group I--3 to 8 years old; Group II--9 to 16 years old; and Group III--17 to 35 years old). In Group I there were 84 pre-school children; in Group II there were 146 schoolchildren; in Group III there were 151 dental students and dental nurse students. The prevalence of variations in the morphology of the tongue surface in the three groups combined was as follows: fissured tongue, 5.0 percent; filiform atrophy, 5.5 percent; geographic tongue, 2.1 percent, and hairy tongue, 8.3 percent. Prevalence of both fissured tongue (p less than 0.05) and filiform atrophy (p less than 0.01) increased with the age of the population. Geographic tongue and hairy tongue did not increase significantly with age. Fissured tongue was more common in males than in females (p less than 0.05). The amount of filiform atrophy and hairy tongue was not significantly different in males and females.

Adolescent↗
PubMed1982

The pH of stimulated and resting saliva in different morphologic forms of the tongue surface in a young population.

Salivary condition and its correlation to tongue morphology was studied in 149 dental students. The students were divided according to the morphologic form of the tongue. The salivary pH and the buffer capacity of resting and stimulated saliva were determined. The pH values in the resting saliva of the fissured tongue group were more alkaline than those in the control group. The difference in pH values of stimulated saliva in the fissured tongue and control groups was only indicative. The stimulated saliva values of the normal tongue and the geographic tongue groups were similar. The pH valves of resting saliva in the geographic tongue group were more acidic than those in the normal tongue group. The salivary pH values of the filiform atrophy group were more acidic than those of the control group: resting salivar highly significantly and stimulated saliva significantly. The pH values of the hairy tongue group were also more acidic than those of the control group: both resting saliva and stimulated saliva highly significantly. No differences were observed in salivary buffer capacity, although buffer capacity in the hairy tongue group seemed to be lower than in the other groups.

Adult↗
PubMed1982

Subcutaneous emphysema.

Swelling appeared in an eight-year-old girl after amalgam restoration. The swelling, subcutaneous emphysema, due to the presence of air in the connective tissue disappeared over a period of two days; no complications occurred. The clinical importance of subcutaneous emphysema is that the migration of air to the mediastinum can cause death. According to the literature, many dental and oral procedures can cause subcutaneous emphysema. Since it can cause many complications due to infection, prophylactic antibiotic therapy is necessary.

Child↗
PubMed1979

Copper allergy and copper IUD.

Epicutaneous tests with copper, nickel and cobalt were performed in 37 patients using copper IUD who had shown side-effects to the IUD. None of them was allergic to copper; four were allergic to nickel and one to cobalt. Metal allergy was not considered to be the cause of the side-effects in any of the patients.

Adult↗