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PubMed1994

A dedicated MRI apparatus for medical and industrial applications.

So far, one of the major obstacles to the development of special purpose MRI imaging apparatus has been the lack of a magnetic technology that could cater to the need for a light, compact and efficient magnet, capable of providing the required field uniformity at a reasonable cost. Today, recent advances in magnet design permit attaining, with the use solely of ferrite, low-cost, small-scale scanners, which can open up new areas of application of MRI, in both medical and industrial fields. A novel apparatus (ARTOSCAN) is described and some examples of applications in different fields are shown. The apparatus has been designed specifically for the imaging of extremities, but possible applications on the industrial side are numerous and not yet all identified. Such a device could be used, for example, in the agricultural, food, and oil industries, where some of the needs for nondestructive quality-control devices could be fulfilled. Some tests have been performed that demonstrate the potential of the apparatus in the study of rock properties, of the drying process of pasta and wood, and to display flaws that could be present in ceramic materials before firing.

Equipment Design↗
PubMed1996

Collagenolytic activities with differentiation of the cultured cells from the murine hair apparatus.

Immature hair apparatus cells were cultured for 3 days to allow to proliferate and differentiate into several subpopulations including hair-shaft type cells on day 6. Zymographic and immunocytochemical studies of the culture media were performed to examine whether the differentiated and/or immature cells from the murine hair apparatus can secrete type IV collagenases. Zymography showed the presence of 72 and 92 kDa type IV collagenases in media, in which hair apparatus cells had been cultured for 3 and 6 days. Most of the cells cultured for 3 and 6 days showed positive reactions with the mouse anti-gelatinase monoclonal antibody in the perinuclear cytoplasm. These data suggest that the differentiated cells as well as immature cells in the hair apparatus may retain the ability to produce and secrete 72 and 92 kDa collagenases.

Animals↗
PubMed2005

An automated apparatus for the real-time monitoring of bioluminescence in plants.

We developed an automated, high-throughput, bioluminescence-monitoring apparatus that can monitor 1920 individual plant seedlings under uniform light conditions. The apparatus is composed of five units: (i) a plate platform that can hold 20 96-well microplates under uniform light conditions, (ii) a scintillation counter, (iii) a robot that conveys plates between the plate platform and a scintillation counter, (iv) a sequence controller, and (v) an external computer that collects and analyzes bioluminescence data automatically. The apparatus gave reproducible and reliable results for both bioluminescence photon counts and period length of bioluminescence rhythms; neither was affected by the well position in a plate or the plate position on the platform. The apparatus is a powerful tool for both large-scale detailed analysis of gene expression and large-scale screening of mutants.

Arabidopsis↗
PubMed2005

Capillary electrophoresis apparatus equipped with a bioluminescence detector using a batch- or flow-type detection cell.

We developed a capillary electrophoresis (CE) apparatus equipped with a batch- or flow-type bioluminescence (BL) detection cell. Firefly luciferin-luciferase BL reaction was used to analyze samples of nucleotides, such as ATP, dATP, ADP, GTP, UTP, CTP, ITP, and TTP. In the CE apparatus with the batch-type cell, ATP was detected at concentrations of 5-100 microM, while the other nucleotides were not detected at concentrations less than 500 microM. The electropherogram of ATP included two BL peaks; the latter peak showed peculiar broadening, which continued up to ca. 2.5 h. In the CE apparatus with the flow-type cell, ATP, dATP, and ADP were detected with single peaks with detection limits of 1, 75, and 100 microM, respectively. The other nucleotides, GTP, UTP, CTP, ITP, and TTP, were not detected at concentrations less than 0.5 mM. A mixture of 10 microM ATP and 100 microM dATP was examined using the CE apparatus with the flow-type BL detection cell. ATP and dATP were separated using running buffer at pH 10 containing 1 mM phenylboronic acid. The interaction between ATP and phenylboronic acid delayed the migration time of ATP.

Electrophoresis, Capillary↗
PubMed2005

Long-term preservation using a new apparatus combined with suppression of pro-inflammatory cytokines improves donor heart function after transplantation in a canine model.

OBJECTIVE: We developed a new apparatus for long-term heart preservation that combines simple immersion with coronary perfusion. In a previous study, we reported that suppression of pro-inflammatory cytokines, such as tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta), improved results after transplantation. In this study, we evaluated whether long-term preservation using our apparatus for continuous coronary perfusion, combined with suppression of pro-inflammatory cytokines, improves donor heart function after transplantation in a canine model. METHODS: We used adult mongrel dogs in this study. Coronary vascular beds were washed with University of Wisconsin (UW) solution after arresting hearts with glucose-insulin-potassium solution. The heart was then excised and preserved for 12 hours with a combination of immersion and coronary perfusion using a preservation apparatus. Adult mongrel dogs were divided into 2 groups: the coronary perfusion (CP) group (n = 7) and the FR167653 (FR-CP) group (n = 6). In the CP group, we used a 4 degrees C UW solution for immersion and coronary perfusion. In the FR-CP group, we used a 4 degrees C UW solution supplemented with 20 mg/liter of the anti-inflammatory agent FR167653 for immersion and coronary perfusion. At 2 and at 3 hours after orthotopic transplantation, we compared hemodynamic parameters with pre-operative values in donor animals, with right atrial pressure at 10 mm Hg and with 5 microg/kg/min dopamine infusion. We compared serum concentrations of TNF-alpha from the coronary sinus and compared electron microscopic studies between the 2 groups. RESULTS: Three hours after transplantation, cardiac output (CO), left ventricular pressure (LVP), and -LVdp/dt were significantly greater (p < 0.05) in the FR-CP group than in the CP group (CO, 178% +/- 65% vs 93% +/- 40%; LVP, 115% +/- 22% vs 73% +/-26%; -LVdp/dt, 168% +/- 13% vs 61% +/- 17%, respectively). Electron microscopic studies showed that glycogen was well preserved in the FR-CP group compared with the CP group. Serum concentrations of TNF-alpha were decreased significantly in the FR-CP group compared with the CP group at 3 hours after reperfusion (161 +/- 54 pg/dl vs 642 +/- 636 pg/dl, respectively). CONCLUSION: Hemodynamics after transplantation were significantly better in the FR-CP group than in the CP group. The combined preservation method of continuous perfusion and immersion using our apparatus in conjunction with suppression of pro-inflammatory cytokines improves donor heart function after transplantation.

Animals↗
PubMed1998

The division apparatus of plastids and mitochondria.

Mitochondria and plastids in eukaryotic cells contain distinct genomes and multiply in the cytoplasm by binary division of preexisting organelles. Mitochondrial and plastid nuclei are easily visualized as compartments in the matrix of organelles by high-resolution fluorescence microscopy and by immunoelectron microscopy using anti-DNA antibodies. Plastid and mitochondrial division can be clearly separated into two main events: division of the organelle nuclei, and then division of the rest of the organelles, the process of organellokinesis (mitochondriokinesis and plastidokinesis). The mechanical apparatus that regulates organellokinesis has remained undetermined. In 1986, the plastid-dividing apparatus (PD ring) for plastidokinesis was first identified by us in the primitive red alga Cyanidium caldarium RK-1. The PD ring is located in the cytoplasm outside the organelle envelope at the constricted isthmus of dividing organelles and has subsequently been found in all eukaryotic plants examined. We were also the first to identify the mitochondrion-dividing apparatus (MD ring) for mitochondriokinesis in the unicellular red alga Cyanidioschyzon merolae in 1993. Eukaryotic cell division is therefore controlled by at least three dividing apparata (rings), a contractile ring, an MD ring, and a PD ring, while bacterial division is controlled by a single bacterial contractile FtsZ ring. The aims of this review are to present the fine structure, process of formation, and contraction of the organelle-dividing apparatus, focusing on evolutionary conservation and diversion from the bacterial contractile ring.

Cell Division↗
PubMed2000

A culture apparatus for maintaining H2 at sub-nanomolar concentrations.

We devised a microbial culture apparatus capable of maintaining sub-nanomolar H2 concentrations. This apparatus provides a method for study of interspecies hydrogen transfer by externally fulfilling the thermodynamic requirement for low H2 concentrations, thereby obviating the need for use of cocultures to study some forms of metabolism. The culture vessel is constructed of glass and operates by sparging a liquid culture with purified gases, thereby removing H2 as it is produced. We used the culture apparatus to decouple a syntrophic association in an ethanol-consuming, methanogenic enrichment culture, allowing ethanol oxidation to dominate methane production. We also used the culture apparatus to grow pure cultures of the ethanol-oxidizing, proton-reducing Pelobacter acetylenicus (WoAcy 1), and to study the bioenergetics of growth.

Anaerobiosis↗
PubMed2002

New-types of apparatus for producing microcapsules and microgranules.

Two types of simple compact apparatuses for microencapsulation and microgranulation have been developed. The vibration-type apparatus is a better fit for producing gel-like microgranules of 1.5-3.0 mm in diameter to be used in production of food (fodder) products and additives and microgranulated cell culture. The spray apparatus is fit for operation in two modes: drop-forming (particles of 100-500 microm in diameter) and spray modes (particles of 10-50 microm in diameter). The apparatus is most efficient when used in the mode of forming the particles directly in the medium of liquid nitrogen with successive lyophilic drying (without preliminary defrosting). It is used for microgranulating the live virus materials with their virulence being preserved.

Acrylic Resins↗
PubMed2003

Design and evaluation of an early stage drug release apparatus.

This paper describes the design and evaluation of an early stage drug release apparatus (ERA) to determine drug release from pellets at times less than 1 min. The apparatus comprises a stirred sample chamber in which the sample is retained by a BS150 mesh screen (0.106 mm), and a series of jacketed cups containing the medium (80 ml) which are raised and lowered in turn over the fixed sample chamber for specified periods. Three types of early release studies were used: single 60s study (single cup), 10s followed by 50s (two cups) and 10, 20, 30...60s multiple changeover differential release (six cups). The effects of stirrer speed, stirrer position and multiple changeover on drug release from standard paracetamol-alginate pellets were investigated. Drug release rates from non-disintegrating pellets were reproducibly determined. The three types of early release study schemes yielded reproducible drug release data over sampling times less than 1 min. Stirrer speed, and depth, and changeover motion of release cups affected drug release but yielded reproducible results. Release from the standard pellets used to study the apparatus took 3 days to stabilize and remained stable thereafter. The apparatus can be used for screening of pellet formulations of sparingly soluble drugs during their developmental stage and regular quality assurance studies of pellets (>150 mesh size). Along with early release studies of pellets, it could be easily modified to study other types of formulations and for automation.

Drug Implants↗
PubMed1999

The function of the disco-muscular apparatus in the human temporomandibular joint.

The morphology and function of the disco-muscular apparatus of the human TMJ is a controversial subject. Connections between the muscles which move the mandible and the "disco-capsular complex" have been described in a contradictory way. The disco-muscular apparatus is also described as being more extensive than that of the M. pterygoideus alone to include to the Mm. temporalis and masseter. However, the involvement of the latter is considered to be a peripheral variation of the normal anatomy and of little, if any, functional significance. The existence of independent relationships between the deep portions of the masseter and temporal muscles and the disco-capsular apparatus of the human TMJ is rarely discussed or explained. The morphologic findings were derived from fixed and unfixed human temporomandibular joints (TMJ) of varying ages and both sexes, whereby the functional maturity of the masticatory apparatus was taken into consideration. The results of the study show that aside from fibers originating from the superior venter of the M. pterygoideus lateralis, additional muscle or connective tissue fibers from the perimysium of the M. masseter are inserted to varying extents into the disc. The same is true for the M. temporalis, which is also directly connected to the disc via muscular or fibrous elements, or indirectly via fibers from the M. masseter. The insertion of the M. pterygoideus lateralis is always in the medial portion of the Discus articularis and those of the Mm. temporalis and masseter in the middle and lateral portions of the disc respectively. It is highly probable that a direct force transfer through the Mm. temporalis and masseter to the articular disc takes place, and that these muscles contribute to the movement of the disc during jaw movement, whereas the size and form of the muscle insertions are subject to a great deal of individual variation.

Adolescent↗
PubMed2003

Experience with bicanalicular intubation of the lacrimal drainage apparatus combined with conventional external dacryocystorhinostomy.

AIM: The aim of this study was to assess the success rate of bicanalicular intubation of lacrimal drainage apparatus in chronic dacryocystitis patients who were at high risk of failure of surgery of dacryocystorhinostomy. MATERIAL AND METHODS: A total of 24 patients with chronic dacryocystitis (25 eyes) including 11 males and 13 females (age range 3-80 years) having high risk factors of failure of dacryocystorhinostomy were enrolled. Factors such as previous attacks of acute dacryocystitis, trauma in lacrimal sac region, previously failed dacryocystorhinostomies, formation of false passages in the lacrimal drainage apparatus were considered. Conventional dacryocystorhinostomy followed by bicanalicular intubation of the lacrimal drainage apparatus with Jain metal silicone the lacrimal intubation tube (20-23 gauge) was performed in all these patients. The patients were followed up at weekly intervals for two months, at 6 months and at 1 year post surgery. RESULTS: A total of 25 eyes in 24 patients (including 11 males and 3 females) were operated upon using the technique of bicanalicular intubation of lacrimal drainage apparatus with conventional external dacryocystorhinostomy. The procedure was successfully performed in 22 out of the 25 eyes. Perioperative complications included punctual damage due to recurrent attempts at passing these probes in 2 patients and mild damage to nasal mucosa in 5 patients. The majority of patients did not experience any untoward symptoms from these silicone tubes. However, in three eyes there was felt a mild foreign body sensation and two patients had chronic conjunctival erythema. The tubes could not be retained in two of these three eyes. Additionally, in one eye there was spontaneous extrusion of tubes whilst sneezing 3 months after surgery. All these three eyes had a recurrence of symptoms due to non-retention of the tubes and needed re-operation. On average the tubes were retained for a period of six months before they were spontaneously extruded or removed. Fifteen patients retained the silicone tubes for more than 1 year. The procedure gave a success rate of 76% (19/25 eyes) and these were the eyes in which the tubes had been retained for more than 6 months. The success was not influenced by the age or sex of patient, laterality of eye, aetiology of chronic dacryocystitis, or evidence of bony deformity or abnormality of the sac. CONCLUSIONS: Bicanalicular intubation for lacrimal drainage system is a simple, inexpensive and straight forward adjunct to conventional external dacryocystorhinostomy. The procedure is strongly indicated for patients with chronic dacryocystitis who are at high risk of surgical failure. Carefully performed, it gives a 76% success rate and is not influenced by the different variables examined.

Adolescent↗
PubMed2001

Galactolipids not associated with the photosynthetic apparatus in phosphate-deprived plants.

The galactolipid digalactosyldiacylglycerol (DGGD) is one of the major constituents of thylakoids, accounting for about 25% of polar lipids found in these membranes. Although the presence of DGDG has frequently been correlated with the structural and functional integrity of the photosynthetic apparatus, it is still a matter of debate of what the in-vivo function of DGDG actually might be. To further the understanding of the role of DGDG within the photosynthetic apparatus, experiments were conducted on different Arabidopsis thaliana lines with altered DGDG content. The dgd1 mutant is characterized by a 90% reduction in the DGDG content, resulting in a severe dwarfism during growth. Complementation of the dgd1 mutant with a DGD1 cDNA completely restored the wild-type characteristics, while photosynthesis-related parameters were intermediate in transgenic plants with a partial reduction in DGD1 activity caused by post-transcription gene silencing due to over-expression of a DGD1 cDNA in wild-type plants. These data provide clear evidence for a causal relationship between the DGDG content, and the structure and function of the photosynthetic apparatus. However, a significant DGDG accumulation in the dgd1/pho1 double mutant was without any detectable effect on photosynthetic activity, indicating that the molecular DGDG species synthesized upon phosphate deprivation in leaves cannot substitute for the DGDG species present under normal nutrient supply of plants. It is suggested that depending on the environmental growth conditions different pools of DGDG species exist in plants of which one is not associated with the photosynthetic apparatus.

Arabidopsis↗
PubMed1999

Long-term heart preservation using a new portable hypothermic perfusion apparatus.

OBJECTIVE: Perfusion storage is not often used clinically compared with simple immersion because of complicated circuits and demanding management. We developed a new apparatus for preservation combined with simple immersion and continuous coronary perfusion. METHODS: The main characteristics of this apparatus are as follows: (1) hypothermic storage, (2) does not require any energy source, (3) variable perfusion pressure, and (4) portability. The perfusion apparatus is composed of a storage chamber, a cooling chamber, and metal bars from which a perfusate bag is suspended. Adult mongrel dogs were divided into two groups: the coronary perfusion group (CP, n = 6) and the simple immersion group (SI, n = 6). Coronary vascular beds of the dog were washed out with a University of Wisconsin (UW) solution following cardiac arrest obtained using a GIK solution. The hearts were then excised. In the CP group, the heart graft, which was immersed in a 4 degrees C UW solution, was perfused with the same solution at a flow rate of 35 approximately 50 ml/hr. In the SI group, the heart graft was immersed in a 4 degrees C UW solution only. The heart graft was preserved for 12 hours in both groups. Beta-adenosine triphosphate (beta-ATP), phosphocreatine (Pcr), and inorganic phosphate (Pi) levels were measured immediately after excision of the heart, and at 3, 6, and 12 hours after preservation. Beta-ATP, Pcr, and Pi values were expressed as a percentage of control values, which had been obtained immediately after excision of the heart. Water content of the myocardium was measured prior to and after 12-hour preservation. The preserved graft was then evaluated through orthotopic transplantation. RESULTS: Beta-ATP/Pi levels at 6 and 12 hours after preservation were significantly higher in the CP group than in the SI group (62 +/- 5 versus 39 +/- 7%, 48 +/- 5 versus 22 +/- 8%, respectively, p < 0.05). Pcr/Pi levels at 6 and 12 hours after preservation were 30 +/- 9% and 22 +/- 8%, respectively in the CP group, while Pcr/Pi levels in the SI group were detected in only one case. There was no significant difference in water content either prior to or after 12-hour preservation between the two groups. Histopathologically, irregular expansion and/or contraction of myocardial fibers were more severe in the SI group than in the CP group. The recovery rate of hemodynamic parameters 2 hours after heart transplantation was significantly (p < 0.05) higher in the CP group than in the SI group. CONCLUSION: Stable and safe long-term canine heart preservation with continuous coronary perfusion associated with immersion is possible using this new apparatus, and may have broad clinical application.

Adenosine↗
PubMed1995

Measurement of small tissue volumes using Holden's apparatus.

A reproducible method for the estimation of volumes of small tissue samples was needed to allow comparison of the biological activity of tissue explants and to relate symptom improvement to procedures such as adenoidectomy or polypectomy. Holden's apparatus, which utilizes fluid displacement between two chambers, was compared to displacement in a 20 ml syringe. Two observers made four readings each on 20 tissue samples (range 0.37 to 4.70 ml) using both methods for comparison. A two-way analysis of variance for replicated data gave an F ratio of 0.6885 (df = 19; p > 0.8) for Holden's apparatus, and an F ratio of 1.4307 (df = 19; p > 0.1) for the 20 ml syringe. The standard error of the mean for repeated readings on the same sample by an observer was 0.001 ml for Holden's apparatus and 0.014 ml for the syringe method. For accurate estimation of small tissue volumes within 0.01 ml we recommend Holden's apparatus.

Adenoids↗
PubMed2000

Temperature-controlled microscopy for imaging living cells: apparatus, thermal analysis and temperature dependency of embryonic elongation in Caenorhabditis elegans.

A new experimental apparatus for temperature-controlled microscopy has been developed for the study of the temperature dependency of developmental processes in the nematode Caenorhabditis elegans. However, the application of this apparatus is rather general and can be used for a wide range of temperatures between - 10 and 90 degrees C. The new apparatus is easy to use, inexpensive, simple to construct, and is designed for precise temperature control of oil-immersion microscopy using epifluorescence. Thermal analysis of the experimental apparatus shows the effects of each of its components, as well as the effects of uncertainty in temperature measurements. Finally, results of this study indicate that: (i) embryos incubated and imaged at temperatures of 8 degrees C and below do not elongate; (ii) the initial elongation rate is strongly temperature-dependent between 9 and 25 degrees C.

Animals↗
PubMed1990

Transfer of free vascularized bone and skin-bone autografts: experiences in the application of external fixation apparatus.

The results of transfer of free vascularized bone and skin-bone autografts in 95 patients with defects (54) and nonunions (41) of tubular bones of different genesis are presented. In 71 cases, an external fixation apparatus was used for purposes of osteosynthesis. In 50 cases, the Ilizarov apparatus was applied prior to osteoplasty to correct deformity and fully or partially to correct a shortening of the extremity bone segment. In seven cases, lengthening of the bone segment was performed using an external fixation apparatus after osteoplastic reconstruction of the defect. Treatment was completed in 76 cases (80.0 percent); of these, the outcome was positive in 89.5 percent of cases. Failure was recorded in 10.5 percent of cases. The advantages of using an external fixation apparatus in combination with vascularized bone and osteocutaneous autografts are discussed.

Adolescent↗
PubMed1981

Cooperation of kinetochores and pole in the establishment of monopolar mitotic apparatus.

Monopolar mitotic apparatus can be produced in sea urchin eggs by a manoeuvre that distributes the four poles of the second mitosis into four separate blastomeres. The pole of the monopolar mitotic apparatus generates a half-spindle that is similar in structural details to the half-spindle of a normal bipolar mitotic apparatus, although the chromosomes are not as well aligned as in a normal metaphase plate. The chromosomes are oriented; one kinetochore faces the pole while its sister kinetochore faces away from the pole. The poleward kinetochore is connected to the pole by bundles of microtubules. No microtubules are seen on the sister kinetochore that faces away from the pole. Therefore, a single pole can direct most of the events in the establishment of a mitotic apparatus. Our interpretation examines the cooperation of kinetochores and poles in the formation of microtubules between them, stressing the half-spindle as the medium of cooperation and leaving open the question whether the kinetochores are origins or terminations of microtubules.

Animals↗
PubMed2004

Associations of the major pseudopilin XpsG with XpsN (GspC) and secretin XpsD of Xanthomonas campestris pv. campestris type II secretion apparatus revealed by cross-linking analysis.

The major pseudopilin XpsG is an essential component of type II secretion apparatus of Xanthomonas campestris pv. campestris. Along with other ancillary pseudopilins, it forms a pilus-like structure spanning between cytoplasmic and outer membranes. Associations of pseudopilins with non-pseudopilin members of type II secretion apparatus were not well documented, probably due to their dynamic or unstable nature. In this study, by treating intact cells with a cleavable cross-linker dithiobis(succinimidylpropionate) (DSP), followed by metal chelating chromatography and immunoblotting on secretion-positive strains of X. campestris pv. campestris, we discovered associations of XpsGh with XpsN (GspC), as well as XpsD. These associations were detectable in a strain missing all components, but XpsO, of the type II secretion apparatus. However, chromosomal non-polar mutation in each gene exerted different effects upon the association between the other two. The XpsGh/XpsD association is undetectable in xpsN mutant; however, it was restored to a limited extent by overproducing XpsD protein. The XpsGh/XpsN association is unaltered by a lack of XpsD protein or an elevation of its abundance. Co-immune precipitation between XpsN and XpsD, while being independent of XpsG, was nonetheless enhanced by raising XpsG protein level. These observations agree with the proposition that the type II secretion apparatus in a cell may exist as an integrated multiprotein complex with all components working in concert. Moreover, in functional machinery, the association of the major pseudopilin XpsG with secretin XpsD appears strongly dependent on the existence of XpsN, the GspC protein.

Bacterial Proteins↗