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PubMed1997

Ropy slime-producing Lactobacillus sake strains possess a strong competitive ability against a commercial biopreservative.

Aseptically handled Frankfurters were treated with a commercial Lactobacillus alimentarius biopreservative and inoculated with different cell concentrations of four ropy slime-producing Lactobacillus sake strains. The packages were vacuum sealed and kept at 6 degrees C for 28 days, after which the production of ropy slime was evaluated. The inoculation test was controlled by sealing the different control packages containing either aseptically manufactured sausages without any bacterial inoculation, packages containing biopreservative only or packages inoculated only with the four different ropy slime-producing strains. Authenticity of the biopreservative strain after the cold storage period was ascertained by performing EcoRI restriction endonuclease analysis of 30 randomly selected isolates originating from the biopreservative control packages. All patterns were identical to the pattern of the original L. alimentarius biopreservative strain. The biopreservative was found to be ineffective against the four ropy slime-producing L. sake strains. The strongest slime producers inoculated with approximately 1 colony forming units (CFU)/cm2 could compete efficiently with the L. alimentarius inoculated at a level of 10(7) CFU/cm2 on sausage surfaces. This commercial biopreservative failed to occupy the vital niche of the four ropy slime-producing L. sake strains leading to spoilage in almost all packages.

Food Packaging↗
PubMed1987

Proximal retinal contribution to the intraretinal 8-Hz pattern ERG of cat.

We investigated the retinal depth of origin of the pattern ERG (PERG) in cat by recording extracellular responses to contrast reversal grating stimuli and performing a current source-density analysis of the depth profiles. The local ERG (LERG) was recorded within the retina; the waveform varied with grating spatial phase position of the microelectrode. The LERG at any arbitrary single spatial phase was not equivalent to the corneal PERG. To obtain an "intraretinal PERG" equivalent to the corneal PERG, we summed LERGs from many spatial phases over a complete grating cycle. This intraretinal PERG was analogous to the corneal PERG in having only even harmonic components and also in being independent of the grating spatial phase. The absence of the fundamental and odd harmonics appeared to result from the summation of responses across grating spatial phase rather than from an intrinsic generator mechanism. The spatial contrast sensitivity function for the intraretinal PERG at 8 Hz was tuned, with peak sensitivity between 0.5 and 0.75 cycles per degree in the area centralis. The 8-Hz PERG response was maximum in the proximal retina at approximately 23% depth from the internal limiting membrane (ILM). This depth lies within the inner plexiform layer and is proximal to the depth at which the b-wave was maximum (49-61% depth). PERG and flash-elicited ERG responses exhibited different amplitude profiles as a function of retinal depth. Analysis of the 8-Hz PERG depth profiles identified generators in the proximal retina between the ILM and the inner plexiform-inner nuclear boundary. The analysis suggested that at least two generators were present. The proportional contribution to the corneal PERG from each of the two or more proximal generators was not determined. Contributions to the corneal PERG from more distal generators, however, were not specifically excluded. The intraretinal recordings suggest that under some conditions contrast reversal gratings at 8 Hz can elicit current generators in the proximal retina of cat. These generators appear to respond to local retinal illumination, and the intraretinal PERG results from nonlinear elements of at least two generators. Spatial tuning of the intraretinal PERG may reflect properties of the underlying LERG components, including the M-wave.

Animals↗
PubMed1975

Pancreatitis of unusual origin.

The anatomic pattern seen in the three patients with contiguous gastric duplications associated with pancreatic ducts evidently predisposes the patient to pancreatitis. In the previous patient reported upon from this institution, the correlation of severe bleeding episodes with attacks of pancreatitis strongly supports the concept of blood blocking the pancreatic ductal system, thereby producing pancreatitis. Passage of viscous mucoid secretions from the aberrant gastric mucosa into the pancreatic ductal system also might retard the normal flow of pancreatic juice, producing elevation of the serum amylase level and pain. Overdistention of the gastric duplication also might be considered as a source of pain, but such mechanisms can be considered only speculation at present. Diagnosis is usually made after more than one exploratory laparotomy. Hemorrhage may result, should the gastric duplication contain parietal cells, leading to hemoductal pancreatitis, hematemesis or melena and anemia. At least one in five patients with a gastric duplication possesses another intestinal duplication. Developmental defects commonly are associated with gastric cysts. Almost identical anatomy was present in the patients with contiguous duplications. That two such rare pancreatic disorders were documented in the same institution within two years suggests that this pattern of developmental defect is more common that had previously been expected.

Adolescent↗
PubMed2005

Investigation of genetic heterogeneity in Mycobacterium tuberculosis isolates from tuberculosis patients using DNA fingerprinting.

BACKGROUND: DNA fingerprinting of Mycobacterium tuberculosis (MTB) based on IS6110 has been shown to be a powerful epidemiologic tool. Restriction enzyme analysis (REA) is a fingerprinting technique, which is used for differentiation and investigation of genetic diversity among mycobacterial species. AIMS: To investigating the genetic heterogeneity in MTB isolates in Ahvaz, Iran. SETTINGS AND DESIGN: It was a cross-sectional study conducted in Ahvaz, Iran. METHODS AND MATERIAL: One hundred and eighty clinical isolates of MTB were collected from TB reference unit, PHLS, Ahvaz, Iran. The PCR-REA employed uses a simple DNA extraction followed by a PCR step involving a single primer based on the insertion sequence IS6110. Restriction enzyme analysis was performed on the amplification products using HaeIII enzyme. STATISTICAL ANALYSIS: Data was analyzed using SPSS software and chi-square test/Fishers' exact test was applied wherever applicable. RESULTS: The isolates were divided into four clusters based on their REA patterns. Cluster I contained 71.1% of strains with two fragments of 72 and 118. Cluster II with three fragments of 72, 118, and 194; cluster III with three fragments of 118, 194, and 234; and cluster IV with four fragments of 72, 118, 194, and 234 base pairs. As many as 73.8% of the identical fingerprint patterns were seen in male patients. Accounting the men as the major population in the study, there was no significant difference between REA patterns and sex; similarly, with age, patients' occupation and degree of smear positivity. However, we found significant correlation between REA patterns and patients' origin. As many as 61.6% of identical patterns were found in the patients who were lived in the same suburb. CONCLUSIONS: By PCR-based REA typing, the isolates studied were grouped into four clusters each containing between two and four fragments. However, in order to ascertain the level of heterogeneity of MTB isolates in their sample, further testing with a more discriminatory method is needed.

Adult↗
PubMedDate not supplied

Clinical and electroencephalographic evidence for sites of origin of seizures with diffuse electrodecremental pattern.

A diffuse electrodecremental ictal pattern (DEP) has been associated with tonic seizures and, less often, with other forms of epilepsy and has been considered to reflect a generalized seizure disorder of diffuse cortical or subcortical (brainstem) origin. In some seizures associated with DEP, however, focal ictal manifestations have been observed. We reviewed the records of all patients admitted to our seizure monitoring unit for 3 years and detected 39 patients with seizures associated with DEP. In 23 of 39 patients, clinical ictal behaviors resembled seizures of unilateral supero/mesiofrontal lobe origin and interictal EEG showed a prominent unilateral frontal component. Nine of 39 had complex absences (CA)/complex partial seizures (CPS); 4 of them were of unilateral frontal lobe origin. Seven of 39 patients had tonic or atonic seizures. Seven patients were studied further with subdural electrodes. Ictal onsets showed a high-frequency frontal lobe discharge. We conclude that in a subgroup of patients a generalized electrodecremental pattern on scalp EEG results from a regional cortical high-frequency ictal discharge originating in a single frontal lobe.

Adult↗
PubMed1972

Temporal pattern of neurogenesis in spinal cord: cytoarchitecture and directed growth of axons.

Neurogenesis was studied in rat spinal cord by correlation of the observations from [(3)H]thymidine autoradiography and Golgi techniques. The temporal pattern of the origin of neurons systematically lagged along the ventro-dorsal and rostro-caudal axes. The temporal pattern was correlated with the topographic pattern of the release and segregation of the newly formed neuroblasts from the neuroepithelium. These temporal and topographic patterns of neuroblast genesis imparted an order to the settling of the neuroblasts. Further, the emerging cytoarchitecture of the differentiating neuroblasts resulted in the formation of oriented interfaces along which the axons grew. The "pioneering" fibers grew along the interfaces formed by the regressed neuroepithelium and the assembled neuroblasts. As development progressed, the axons formed later "selectively fasciculated" along the "pioneering" fibers in a staggered pattern as a result of their differential times of origin. These temporal and topographic patterns occurred in a manner such that the preexisting structure served as an "organizing structure" or foundation upon which the axonal processes formed later in the developmental sequence were oriented and assembled.

Animals↗
PubMed2004

Computerized high-density mapping of the pulmonary veins: new insights into their electrical activation in patients with atrial fibrillation.

AIM: To report the method and findings of computerized high-density mapping of pulmonary veins (PVs) in patients undergoing their electrical isolation for atrial fibrillation (AF). METHODS AND RESULTS: In 17 consecutive patients (8 M, age 55+/-11 years), a 64 electrode basket catheter was placed in the target PVs and 56 bipolar electrograms were recorded, analyzed and isochronal maps were generated. PVs were mapped during sinus rhythm, left-sided pacing and ectopic activity. The sites of earliest activation at the veno-atrial junction were defined as the atrium to vein conduction breakthroughs. PV activation pattern was classified as predominantly longitudinal or transverse, according to the direction of the impulse from the breakthroughs. The ectopic pattern was defined as multifocal, when distant areas in the PV had activation times within 10ms. Thirty-one PVs were mapped. The activation pattern was predominantly longitudinal in 13 PVs and transverse in 18 PVs. Two breakthroughs were identified in 22 PVs and three in nine. All the breakthroughs were evident simultaneously in sinus rhythm and left-sided pacing changed only the predominance of the breakthrough. Ectopies were mapped in 10 PVs: eight showed a multifocal and two a monofocal pattern; six ectopies originated from the proximal tract of the PV. CONCLUSION: High-density mapping of PV identifies a typical activation pattern. Multiple and discrete breakthroughs are simultaneously identified in sinus rhythm. The majority of the mapped ectopies has a multifocal pattern and proximal origin.

Atrial Fibrillation↗
PubMedDate not supplied

Distribution of surviving tumor cells after chemoradiotherapy in tongue and floor of mouth carcinomas.

BACKGROUND: Conservative surgery according to the clinical response to induction therapy is applied in breast carcinomas but not yet in head and neck carcinomas. The possibility of conservative surgery after induction therapy for preservation of function was examined. METHODS: Forty-three tongue and 15 floor of mouth carcinomas that had received induction therapy and tumor resection were submitted for a comparative investigation on the clinical effect of induction therapy and cancer cell degeneration, which was examined in semiserial specimens from the bread-loaf sections of the excised materials, and a classification of the surviving tumor cell distribution in the tissue was proposed. The distribution was divided into four patterns according to the dispersion and volume of the remaining tumor cells (pattern I, no surviving tumor cells; pattern IIA, viable tumor cells in the central superficial region of the original tumor tissue; pattern IIB, viable cells in the superficial portion, but distributed widely; pattern III, massive tumor cell nests in the deep portion, but centrally localized; pattern IVA, sporadical viable cell islands, but not in the periphery; and pattern IVB, diffuse viable cells scattered throughout the original tumor tissue). RESULTS: The original tumor size did not affect the remaining viable tumor cell distribution pattern, but sporadic distribution patterns (patterns IVA and IVB) were observed in most of the T4 cases. In many cases, especially in tumors of the nondiffuse invasion type (invasion of grade 1 and 2), the tumor remission rate was inversely correlated with the dispersion of the viable tumor cells. However, some cases of grade 3 and 4 invasion exhibited sporadical surviving tumor cells even though a high tumor remission rate was obtained. These tumors, especially those located on the floor of the mouth, recurred with high frequency. CONCLUSIONS: Conservative surgery can be applied to nondiffuse invasion cases, according to the tumor remission rate. In T3 and T4 cases exhibiting grade 3 or 4 invasion, conservative surgery is ill-advised, even if more than 90% tumor remission is obtained.

Carcinoma↗
PubMed2004

Improvement of CDG diagnosis by combined examination of several glycoproteins.

Congenital disorders of glycosylation (CDG) represent a family of genetic diseases with broad clinical presentation. Initial diagnosis is currently mainly based on the identification of hyposialylated serum transferrin (TF) by isoelectric focusing (IEF). To improve the diagnosis of known CDG types and to identify so far unknown CDG cases, additional glycoproteins, alpha1-antitrypsin titrypsin (alpha1-AT) and alpha1-antichymotrypsin (alpha1-ACT), were studied. According to the patterns of transferrin, enzyme assays and mutation analysis, 16 patients with various clinical symptoms suspicious for CDG were divided into three groups: group A (n = 6) with confirmed CDG; group B (n = 4) with clear abnormal TF-IEF patterns of unknown origin (all known CDG types were excluded) and group C (n = 6) with borderline TF-IEF patterns; 164 samples served as a control group. Automated IEF of TF, alpha1-AT and alpha1-ACT was carried out using a PhastSystem. CDG patients with glycosylation defects of known origin (group A) and patients with abnormal TF-IEF patterns due to glycosylation defects of as yet unknown origin (group B) showed abnormal IEF patterns of all three glycoproteins. These results confirmed generalized defects of glycosylation. Furthermore, the IEF pattern of alpha1-ACT seems to allow a differentiation between CDG Ia and CDG Ic. However, patients with borderline TF-IEF pattern (group C) showed a normal alpha1-AT-IEF pattern. Four of these six patients also showed a normal alpha1-ACT-IEF pattern; this constellation suggests that CDG can most likely be excluded. In the two remaining patients of group C with a borderline TF-IEF pattern an abnormal pattern of alpha1-ACT-IEF was obtained which needs further investigations. We conclude that the combined investigation of three glycoproteins provides additional information in the diagnostic work-up of patients with possible CDG. The suspicion of CDG in patients with apparent glycosylation defects of unknown origin or borderline TF-IEF pattern can be either substantiated or weakened.

Adolescent↗
PubMed1988

Adenocarcinomas of major and minor salivary gland origin: a histopathologic review of treatment failure patterns.

Fifty-four cases of adenocarcinoma of major and minor salivary gland origin were seen between 1960 and 1980. Fifty of these were treated definitively. Planned surgery combined with radiation was the initial treatment for 22 patients (44%), surgery alone for 15 (30%), and radiation alone for 13 (26%). Of the patients receiving surgery with curative intent, 82% underwent complete resections (i.e., negative margins). Cervical lymph node involvement was present in 23% of cases, and 73% of these patients died of their disease within 3 years. Distant metastases developed in 37% of patients, with a median time of 1 year; 93% of these patients died within 3 years. Histologic grading was performed using objective criteria. Thirty-four percent of tumors were well-differentiated, 27% moderately differentiated, and 39% poorly differentiated. Patients with well-differentiated adenocarcinomas tended to survive disease-free longer and developed fewer distant metastases than those patients with moderately or poorly differentiated tumors.

Actuarial Analysis↗
PubMed1983

Morphological and somatic clonal analyses of pattern triplications.

The growth of pattern triplications induced by a 48-hr 29 degrees C treatment given to larvae homo- or hemizygous for a ts cell-lethal mutation was examined to determine which structures result from new, regulative growth and which are produced by the original imaginal disc cells. Pattern triplications contain one complete leg pattern (orthodrome) and two partial patterns (antidrome and paradrome). The results of two morphological analyses and one somatic clonal analysis suggest that in triplications in which the antidrome and paradrome become more complete distally (diverge) the paradrome is formed by a portion of the original leg pattern, and the antidrome and orthodrome are formed by extra, regulative growth. A different result is suggested for triplications in which the antidrome and paradrome become less complete distally (converge). In these, the orthodrome appears to be formed by the original leg pattern and the antidrome and paradrome by extra growth. These results agree with predictions based on the polar coordinate model of positional information.

Animals↗
PubMed1998

Time-frequency analysis using the matching pursuit algorithm applied to seizures originating from the mesial temporal lobe.

OBJECTIVES: The ability to analyze patterns of recorded seizure activity is important in the localization and classification of seizures. Ictal evolution is typically a dynamic process with signals composed of multiple frequencies; this can limit or complicate methods of analysis. The recently-developed matching pursuit algorithm permits continuous time-frequency analyses, making it particularly appealing for application to these signals. The studies here represent the initial applications of this method to intracranial ictal recordings. METHODS: Mesial temporal onset partial seizures were recorded from 9 patients. The data were analyzed by the matching pursuit algorithm were continuous digitized single channel recordings from the depth electrode contact nearest the region of seizure onset. Tine frequency energy distributions were plotted for each seizure and correlated with the intracranial EEG recordings. RESULTS: Periods of seizure initiation, transitional rhythmic bursting activity, organized rhythmic bursting activity and intermittent bursting activity were identified. During periods of organized rhythmic bursting activity, all mesial temporal onset seizures analyzed had a maximum predominant frequency of 5.3-8.4 Hz with a monotonic decline in frequency over a period of less than 60 s. The matching pursuit method allowed for time-frequency decomposition of entire seizures. CONCLUSIONS: The matching pursuit method is a valuable tool for time-frequency analyses of dynamic seizure activity. It is well suited for application to the non-stationary activity that typically characterizes seizure evolution. Time-frequency patterns of seizures originating from different brain regions can be compared using the matching pursuit method.

Algorithms↗
PubMed1993

An ascending spinal pathway transmitting a central rhythmic pattern to the magnocellular red nucleus in the cat.

The activity of cells in the magnocellular red nucleus (RNm) was recorded extra- and intracellularly in the curarized thalamic cat performing fictive locomotion. The locomotor episodes were detected from the rhythmic activity recorded in the motor nerves of the contralateral hindlimb. It was confirmed that, during fictive locomotion, a large proportion of the rubrospinal cells (56% in our sample) exhibit a rhythmic pattern of activity which is synchronized with the efferent spinal motor nerve activity. On the basis of the intracellular recordings it was established that phases of intense synaptic activity with mixed excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) are involved in this rhythmicity. After eliminating the cerebellar input to the RNm, it was observed that the cells still received intense excitatory and inhibitory inputs, resulting in a continuous modulation of their membrane potential, due to the occurrence of EPSPs and IPSPs. During fictive locomotor-like activity and after elimination of the cerebellar afferents to the RNm, it was observed that the spontaneous PSPs in RNm cells (in the case of 45% of the cells) were organized in repetitive subthreshold bursts occurring in phase relationships with the activity recorded in the motor nerves. Some extracellularly recorded cells (12%) showed a rhythmic firing pattern. It is generally recognized that, in the thalamic cat preparation, the locomotor pattern observed in efferent nerves originates from the central pattern generator (CPG) of the spinal cord. It therefore seems likely that the rhythmicity observed here in the RNm may originate from the spinal CPG and be transmitted through the spino-rubral pathway ascending in the ventral part of the cord. It is concluded that the spino-rubral pathway may transmit both somatosensory information and corollary discharges relating to the activity of the spinal CPG for locomotion.

Animals↗
PubMed1997

Establishment and characterization of spontaneous mesothelioma cell lines derived from F344 rats.

Three mesothelioma cell lines (MeET-4, MeET-5, and MeET-6) established from ascitic fluid of F344 rats with spontaneous abdominal mesothelioma have been maintained through at least 60 passages on the DMEM with 10% FBS. Two of original tumours consisted of epithelioid cells growing in a papillary pattern, while one (original tumour of MeET-5) had sarcomatous areas composed of spindle-shaped tumour cells. The cell line originating from MeET-5 showed a constantly beiphasic growth pattern during the repetitive subcloning, while the other two lines retained a monophasic growth pattern. Although the growth pattern was different, the tumour cells in all three lines were positive for vimentin and keratin and ultrastructurally showed an abundant distribution of glycogen granules in the cytoplasm and numerous long microvilli on all surface. The modal chromosome number of cell lines varied from 41 to 71, and abnormal chromosomes were frequently seen. All cell lines established formed colonies on semi-solid medium and could be successfully transplanted, growing tumour masses in syngeneic rats and thus indicating their malignant nature. Cell lines grew even on a medium with a low concentration of FBS. The evidence suggests that they may produce growth factors that enable them to survive unfavourable medium conditions.

Abdominal Neoplasms↗
PubMed2001

Primate origins: evolutionary change in digital ray patterning and segmentation.

This study presents evidence that the first primates share with extant lemurs, tarsiers, and anthropoids hand proportions unlike those of their close relatives, the tree shrews (Scandentia), colugos (Dermoptera), and plesiadapiforms. Specifically, early primates as well as modern strepsirhines and haplorhines have relatively short metacarpals and long proximal phalanges giving them a grasping, prehensile hand. Limb development was studied in the primate Microcebus murinus and a comparative sample of rodents, artiodactyls, and marsupials to investigate the role of embryonic patterning in the morphogenesis and evolution of primate hand proportions. Comparative analysis shows that the derived finger proportions of primates are generated during the early phases of digital ray patterning and segmentation, when the interzone cells marking the presumptive metacarpo- and interphalangeal joints first appear. Interspecific variation in relative digit and metapodial proportions therefore has high developmental penetrance; that is, adult differences are observed at early ontogenetic stages. The paleontological, comparative, and developmental data are therefore consistent with the hypothesis that the early Cenozoic origin of primates involved an evolutionary change in digital ray pattern formation ultimately yielding a grasping, prehensile hand.

Animals↗
PubMed2005

Epigenetic status of the H19 locus in human oocytes following in vitro maturation.

Imprinting is an epigenetic modification that is reprogrammed in the germ line and leads to the monoallelic expression of some genes. Imprinting involves DNA methylation. Maternal imprint is reset during oocyte growth and maturation. In vitro maturation (IVM) of oocytes may, therefore, interfere with imprint acquisition and/or maintenance. To evaluate if maturing human oocytes in vitro would be hazardous at the epigenetic level, we first determined the methylation profile of the H19 differentially methylated region (DMR). The methylation status of the H19 DMR seems particularly vulnerable to in vitro culture conditions. We analyzed oocytes at different stages of maturation following IVM, germinal vesicle (GV), metaphase I (MI), and metaphase II (MII), using the bisulfite mutagenesis technique. Our results indicated that the unmethylated specific maternal profile for the H19 DMR was stably established at the GV stage. The majority of MI-arrested oocytes exhibited an altered pattern of methylation, the CTCF-binding site being methylated in half of the DNA strands analyzed. Of the 20 MII oocytes analyzed, 15 showed the normal unmethylated maternal pattern, while 5 originating from two different patients exhibited a methylated pattern. These findings highlight the need for extended analysis on MII-rescued oocytes to appreciate the epigenetic safety of the IVM procedure, before it becomes a routine and practical assisted reproductive procedure.

Adult↗
PubMed1999

[Acute myocardial infarct in the setting of a hyperpotassemia: electrocardiographic findings].

Graded hyperkalemia and acute myocardial ischemia are remarkably reflected (and can even be predicted) in the surface ECG when they occur alone. If, however, acute ischemia supervenes in the setting of previous hyperkalemia, the ECG changes are less known. We describe a patient who suffered an acute septal myocardial infarction while his extracellular potassium was high. Changes in the ECG waveform brought about by both acute ischemia and hyperkalemia are emphasized. The origin of a sine-wave ventricular activation pattern, the supraventricular origin and likely sinoventricular conduction, versus ventricular tachycardia is, as well, discussed. Correction of hyperkalemia and other metabolic disturbances, as the first and most important therapeutic target, is critical when the origin and nature of the rhythm are controversial.

Aged↗
PubMed1976

Fast and slow motor units in ageing.

The differences in onset and degree of old age changes in different muscles are explained by the differentiation and different reactivity of fast and slow motor units with respect to physiological, structural and biochemical characteristics. The main changes in the motor units in old age are described. The general basic change is a progressive random disturbance of neuromuscular contact ascribed to a decrease of the trophic function of the neuron. The main motor disturbances in old age, i.e; slowness, decrease of muscle strength and lack of fine coordination are explained in terms of physiological changes in senescent motor units. The reactions of senescent motor units differ from one unit to another as shown, e.g. in denervation, reinnervation and regeneration (transplantation) studies. The trend to a shift from a heterogeneous to a more uniform muscle fibre pattern and the defficiencies in recovery of the original muscle fibre pattern in reinnervation and regeneration of senescent muscle is demonstrated and explained by a decrease of the differentiating capacity of different motor units. The changes in the heterogeneous fibre pattern of skeletal and the homogeneous fibre pattern of the papillary heart muscle in old age are contrasted.

Aging↗