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J Kalinowski

Publications and source records attributed to J Kalinowski.

At least 37 records · Page 2Linked to original sources
PubMed1999

Effects of monitoring condition and frequency-altered feedback on stuttering frequency.

The purpose of the study was to examine stuttering frequency during speaking conditions that are believed to mitigate stuttering frequency both with normal nonaltered auditory feedback (NAF) and a known fluency-enhancing feedback. Specifically, stuttering frequency was examined as a function of three monitoring conditions under NAF and frequency-altered feedback (FAF): no monitoring (i.e., speaking alone, in the absence of audio and visual recording), audiovisual monitoring (i.e., speaking alone with audiovisual recording), and audiovisual monitoring with observers (i.e., speaking with audiovisual recording in the presence of two observers). Seven adults and one adolescent who stutter served as participants. Stuttering frequency was differentially affected across monitoring conditions under each auditory feedback condition (p = .027). Post hoc analyses revealed no significant difference in stuttering frequency between the two conditions in the absence of the observers (i.e., no monitoring vs. audiovisual monitoring) under NAF (p = .45). There was, however, a significant difference in stuttering frequency for the no-monitoring and audiovisual-monitoring conditions relative to the audiovisual-monitoring-with-observers condition (p = .0002). There was no statistically significant difference in stuttering frequency across monitoring conditions under FAF (p > .05). The findings are consistent with the notion that during NAF stuttering frequency varies as a function of hierarchical socio-environmental conditions in which inanimate monitoring conditions constitute one entity. Such a relationship does not exist during FAF.

Adult↗
PubMed1999

Expression of the Corynebacterium glutamicum panD gene encoding L-aspartate-alpha-decarboxylase leads to pantothenate overproduction in Escherichia coli.

The Corynebacterium glutamicum panD gene was identified by functional complementation of an Escherichia coli panD mutant strain. Sequence analysis revealed that the coding region of panD comprises 411 bp and specifies a protein of 136 amino acid residues with a deduced molecular mass of 14.1 kDa. A defined C. glutamicum panD mutant completely lacked L-aspartate-alpha-decarboxylase activity and exhibited beta-alanine auxotrophy. The C. glutamicum panD (panDC. g.) as well as the E. coli panD (panDE.c.) genes were cloned into a bifunctional expression plasmid to allow gene analysis in C. glutamicum as well as in E. coli. The enhanced expression of panDC.g. in C. glutamicum resulted in the formation of two distinct proteins in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, leading to the assumption that the panDC.g. gene product is proteolytically processed into two subunits. By increased expression of panDC.g. in C. glutamicum, the activity of L-aspartate-alpha-decarboxylase was 288-fold increased, whereas the panDE.c. gene resulted only in a 4-fold enhancement. The similar experiment performed in E. coli revealed that panDC.g. achieved a 41-fold increase and that panDE.c. achieved a 3-fold increase of enzyme activity. The effect of the panDC.g. and panDE.c. gene expression in E. coli was studied with a view to pantothenate accumulation. Only by expression of the panDC.g. gene was sufficient beta-alanine produced to abolish its limiting effect on pantothenate production. In cultures expressing the panDE.c. gene, the maximal pantothenate production was still dependent on external beta-alanine supplementation. The enhanced expression of panDC.g. in E. coli yielded the highest amount of pantothenate in the culture medium, with a specific productivity of 140 ng of pantothenate mg (dry weight)-1 h-1.

Amino Acid Sequence↗
PubMed1998

Corynebacterium striatum chloramphenicol resistance transposon Tn5564: genetic organization and transposition in Corynebacterium glutamicum.

The clinical isolate Corynebacterium striatum M82B (formerly Corynebacterium xerosis M82B) carries the 50-kb R-plasmid pTP10 conferring resistance to the antibiotics chloramphenicol, erythromycin, kanamycin, and tetracycline. DNA sequence analysis of the chloramphenicol resistance region revealed the presence of the 4155-bp transposable element Tn5564. The ends of Tn5564 are identical 22-bp inverted repeats flanked by a 6-bp target site duplication. The central region of Tn5564 encodes the chloramphenicol resistance gene cmx, specifying a transmembrane chloramphenicol efflux protein, and an open reading frame homologous to transposases of insertion sequences identified in Arthrobacter nicotinovorans and Bordetella pertussis. Furthermore, the 1715-bp insertion sequence IS1513 encoding a putative transposase of the IS30 family is an integral part of Tn5564 and is located upstream of cmx. For transposon mutagenesis, Tn5564 was transferred to Corynebacterium glutamicum on a mobilizable Escherichia coli plasmid using RP4-mediated intergeneric conjugation. Transposition of Tn5564 in C. glutamicum occurred with a frequency of 3.3 x 10(-8) and resulted in an insertion into target sites containing the central palindromic tetranucleotide CTAG. A Tn5564-induced mutant strain of C. glutamicum was found to carry the transposon in the ftsZ gene region.

Amino Acid Sequence↗
PubMed1998

Isoleucine uptake in Corynebacterium glutamicum ATCC 13032 is directed by the brnQ gene product.

By complementation analysis of an isoleucine-uptake-deficient Escherichia coli strain, it was shown that a 1.6-kb HindIII-StuI fragment of Corynebacterium glutamicum ATCC 13032, located downstream of the aecD gene, encodes an isoleucine uptake system. Sequence analysis revealed that the complementing fragment carried an open reading frame, termed brnQ, that encodes a protein with sequence similarities to branched-chain amino acid carriers of gram-positive and gram-negative bacteria. The brnQ gene specifies a predominantly hydrophobic protein of 426 amino acid residues with a calculated molecular mass of 44.9 kDa. A topology prediction by neural network computer analysis suggests the existence of 12 hydrophobic segments that most probably form transmembrane alpha-helices. A C. glutamicum mutant strain harboring a defined deletion of brnQ in the chromosome showed a considerably lower isoleucine uptake rate of 0.04 nmol min-1 mg (dry mass)-1 as compared to the wild-type strain rate of 1.2 nmol min-1 mg (dry mass)-1. Overexpression of brnQ by means of a tac promotor resulted in an elevated uptake rate for isoleucine of 11.3 nmol min-1 mg (dry mass)-1. Evidently, the brnQ gene encodes the only transport system in C. glutamicum directing isoleucine uptake.

Amino Acid Sequence↗
PubMed1998

Mice lacking the type I interleukin-1 receptor do not lose bone mass after ovariectomy.

We measured the effects of ovariectomy on the bone mass of mice that lacked type I interleukin-1 receptor (IL-I R1 -/- mice) in two genetic backgrounds (C57BL/6 x 129/Sv and C57BL/6) to investigate the role of interleukin-1 in the actions of estrogen on bone. At three weeks after surgery, ovariectomized wild-type mice decreased trabecular bone volume in the proximal humerus by 70% in a C57BL/6 x 129/Sv background and 48% in a C57BL/6 background compared to sham-operated controls. In contrast, there was no significant decrease in trabecular bone mass in IL-1 R1 -/- mice after ovariectomy. The estrogen status of all groups was confirmed by measurement of uterine wet weight. These results demonstrate that a functional IL-1 response pathway is required for mice to lose trabecular bone mass after ovariectomy in this model and they imply that IL-1 is an important mediator of the effects of ovariectomy on bone mass. Hence, therapeutic interventions that block the effects of IL-1 on bone may be beneficial for treating diseases of rapid bone loss such as post-menopausal osteoporosis.

Animals↗
PubMed1998

Quantitative electroencephalogram of posterior cortical areas of fluent and stuttering participants during reading with normal and altered auditory feedback.

In the left and right hemisphere, posterior quantitative electroencephalogram Beta band activity (13.5-25.5 Hz) of seven adult participants who stutter and seven age-matched normal controls was obtained while subjects read text under three experimental conditions of normal auditory feedback, delayed auditory feedback, and frequency-altered feedback. Data were obtained from surface electrodes affixed to the scalp using a commercial electrode cap. Electroencephalogram activity was amplified, band-pass analog-filtered, and then digitized. During nonaltered auditory feedback, stuttering participants displayed Beta band hyperreactivity, with the right temporal-parietal lobe region showing the greatest activity. Under conditions of delayed auditory feedback and frequency-altered auditory feedback, the stuttering participants displayed a decrease in stuttering behavior accompanied by a strong reduction in Beta activity for the posterior-temporal-parietal electrode sites, and the left hemisphere posterior sites evidenced a larger area of reactivity. Such findings suggest than an alteration in the electrical fields of the cortex occurred in the stuttering participants under both conditions, possibly reflecting changes in neurogenerator status or current dipole activity. Further, one could propose that stuttering reflects an anomaly of the sensory-linguistic motor integration wherein each hemisphere generates competing linguistic messages at hyperreactive amplitudes.

Adolescent↗
PubMed1998

A latent trait approach to the development of persistent stuttering.

The premise that stuttering disorders develop according to the orthogenetic principle, preceding in a continuous, unilinear fashion from a state of relative lack of differentiation to a state of increasing differentiation and hierarchic integration, was examined. Responses to Woolf's Perceptions of Stuttering Inventory of 87 individuals who stutter were analyzed using a Rasch 1980 latent trait model for dichotomously scored data. Analyses of responses indicated struggle, avoidance, and expectation through the development of stuttering that became increasingly articulated, integrated, stable, and yet responsive to environmental changes. Four stages of development were noted: Stage I was characterized by the expectation of interruptions in the flow of speech, the addition of unnecessary sounds, and general body tension. Stage II was typified by distinctions between troublesome and not so troublesome words and sounds and between the speaker and various audiences and contexts for speaking. In Stage III, speech control decreased despite more focused and complex efforts to control the environment and the speech apparatus. Stage IV was characterized by automatic scanning of all speech, increasingly uncontrolled body movements, and attempts to produce fluent speech by way of comprehensive changes to sound, rhythm, and pitch. Follow-up of 29 respondents suggested the latent struggle was generally stable over time.

Adolescent↗
PubMed1997

The Corynebacterium glutamicum cglIM gene encoding a 5-cytosine methyltransferase enzyme confers a specific DNA methylation pattern in an McrBC-deficient Escherichia coli strain.

The cglIM gene of the coryneform soil bacterium Corynebacterium glutamicum ATCC 13032 has been cloned and characterized. The coding region comprises 1092 nucleotides and specifies a protein of 363 amino acid residues with a deduced Mr of 40700. The amino acid sequence showed striking similarities to methyltransferase enzymes generating 5-methylcytosine residues, especially to M x NgoVII from Neisseria gonorrhoeae recognizing the sequence GCSGC. The cglIM gene is organized in an unusual operon which contains, in addition, two genes encoding stress-sensitive restriction enzymes. Using PCR techniques the entire gene including the promoter region was amplified from the wild-type chromosome and cloned in Escherichia coli. Expression of the cglIM gene in E. coli under the control of its own promoter conferred the C. glutamicum-specific methylation pattern to co-resident shuttle plasmids and led to a 260-fold increase in the transformation rate of C. glutamicum. In addition, the methylation pattern produced by this methyltransferase enzyme is responsible for the sensitivity of DNA from C. glutamicum to the modified cytosine restriction (Mcr) system of E. coli.

Amino Acid Sequence↗
PubMed1997

Effect of altered auditory feedback on people who stutter during scripted telephone conversations.

The effect of altered auditory feedback (AAF) conditions on stuttering during scripted telephone conversations was investigated. Nine adult participants made 15 scripted telephone calls to business in New York City. Alterations in the participants' auditory feedback signal were generated by a commercially available digital signal processor (Casa Futura Technologies Desktop Fluency System Model BTD-400) that shifted participants' speech one-half octave down in frequency, produced a 50-ms delay, or produced non-altered auditory feedback. The AAF effects produced by the digital signal processor were not perceived by the recipients of the telephone calls. The proportion of stuttering events per scripted telephone conversations were significantly reduced in the AAF conditions relative to the non-altered auditory feedback condition (p = .0004). Stuttering frequency was reduced by 55% and 60% for the FAF and DAF, respectively. These findings demonstrate the applicability of this technology to situations of daily living involving telephone use.

Adult↗
PubMed1997

Effect of monaural and binaural altered auditory feedback on stuttering frequency.

The effect of monaural and binaural alterations in auditory feedback on stuttering frequency was investigated. Eleven participants who stutter read aloud under nonaltered auditory feedback (NAF) and monaural and binaural conditions of frequency altered feedback [(FAF), on-quarter octave shift upward] and delayed auditory feedback [(DAF), 50-ms delay] at a normal speech rate. Relative to the NAF condition, reductions in stuttering frequency of approximately 60%-75% were found with the altered auditory feedback conditions. Post hoc single-df comparisons revealed a reduction in stuttering frequency with altered auditory feedback versus NAF (p < 0.0001), a greater reduction in stuttering frequency for binaural compared to monaural altered auditory feedback (p = 0.028), and nonsignificant differences in stuttering frequencies for right versus left monaural conditions (p = 0.54) and DAF versus FAF (p = 0.70).

Adolescent↗
PubMed1997

A Corynebacterium glutamicum gene conferring multidrug resistance in the heterologous host Escherichia coli.

A chromosomal DNA fragment from the erythromycin-sensitive bacterium Corynebacterium glutamicum ATCC 13032 was shown to mediate resistance against erythromycin, tetracycline, puromycin, and bleomycin in Escherichia coli. Multicopy cloning of the fragment did not cause a resistance phenotype in C. glutamicum. The corresponding gene encodes a hydrophobic protein with 12 potential transmembrane-spanning ex-helical segments showing similarity to drug-H+ antiporters.

Amino Acid Sequence↗
PubMed1997

Formant frequency characteristics of elderly speakers in contextual speech.

The present study measured F1 and F2 formant frequency levels of elderly and young male and female speakers producing the /i/, /ae/, [symbol: see text], /u/, and /a/ vowels in two carrier phrases. Results of a series of ANOVAs showed significant interactions of speaker age x vowel for both F1 and F2 formant frequencies for the male and female speakers. Results suggested that while elderly male speakers exhibit significant alterations in vowel production during contextual speech, elderly female speakers generally maintain formant frequency integrity or appropriate articulatory posturing during contextual vowel productions.

Adult↗
PubMed1997

Effect of speaking into a passive resonator on stuttering frequency.

The effect on stuttering frequency of speaking into a passive resonator was investigated. Eight participants who stuttered read aloud with and without the benefit of the resonator. A statistically significant reduction of approximately 30% in stuttering frequency was observed while the participants spoke with the resonator. These and similar commercially available devices may be employed with individuals who stutter, particularly children, as a means of enhancing fluency.

Adolescent↗
PubMed1997

Effect of frequency altered feedback and audience size on stuttering.

The effect of frequency altered feedback (FAF) and audience size on stuttering frequency was examined. Nine adults who stutter orally read to audiences of two, four and 15 people under conditions of FAF (one-half octave shift down) and non-altered auditory feedback (NAF). There was no statistically significant effect of audience size on stuttering frequency (p > 0.05). A statistically significant reduction in stuttering frequency was found under FAF relative to NAF (p < 0.5). Collapsed across audience conditions, stuttering frequency was reduced by 74%. These findings suggest that FAF may be useful as a treatment tool.

Adult↗