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PubMedDate not supplied

Correlation of sperm motion parameters with fertility in rats treated subchronically with epichlorohydrin.

We investigated the relationship between fertility and sperm motin endpoints in rats treated subchronically with the male reproductive toxicant, epichlorohydrin (ECH). Male rats were given ECH orally for 23 days at dosages of 0, 6.25, 12.5, or 25 mg/kg/day. They were mated twice (at 19 and 22 days) to estimate fertility by (1) detection of fertilized ova (presence of sperm head and tail or two pronuclei) 18 hours after mating and by (2) counting implants on day 14 of gestation. Both indices showed dose-related reductions (P less than 0.001). Motion parameters of cauda epididymal sperm were assessed using the CellSoft computer-assisted sperm motion analysis (CASA) system after the rats were asphyxiated on day 25. Curvilinear velocity, straight-line velocity, linearity, and amplitude of lateral head displacement were reduced in a dose-related manner. The fertility indices, percent fertilized ova, and percent implantation on day 14 of gestation were correlated significantly (r = 0.68; P = 0.0001). The following motion parameters were also correlated significantly with fertility (P less than 0.0003; r1 = percent fertilized ova and r2 = percent implantation): linearity (r1 = 0.42; r2 = 0.40), amplitude of lateral head displacement (r1 = 0.54; r2 = 0.48), curvilinear velocity (r1 = 0.53; r2 = 0.50), straight-line velocity (r1 = 0.55; r2 = 0.50), and percent motile sperm (r1 = 0.42; r2 = 0.32). These results suggest a relationship between toxicant-induced reductions in sperm motion and fertility.

Animals↗
PubMed1990

[Magnetic stimulation of the scalp: the responses of the masseter muscles. I].

Magnetic stimulation of nervous elements is a new neurophysiological technique. It easily succeeds in stimulating the brain motor cortex. We applied this technique to the trigeminal motor system, recording responses in masseter muscles. The magnetic stimulations at 4 cm laterally to the vertex on the biauricular line elicited responses in the contralateral masseter due to activation of motor cortex or adjacent elements along the cortico-nuclear pathway. The ipsilateral responses to the same stimuli and to more lateral ones presented shorter latencies and they were ascribed to direct stimulation of the trigeminal nerve, probably its intracisternal portion. The latency values were 6.9 +/- 0.71 ms and 3.6 +/- 0.3 ms respectively.

Adult↗
PubMed1989

[Experimental study of the influence of removal of the zygomatic arch on craniofacial growth and development].

To observe effects of the procedure on craniofacial growth and development, the author removed 10mm of the right zygomatic arch from rats. The subjects (128 rats) were divided into 3 groups: operation group, sham-operation group, and control group. Surgical removal of the right side of the zygomatic arch was performed on 51 rats; sham operations were performed on 42 rats, and 35 rats served as controls. Operations were performed 30 days after the animals' births. The rats were sacrificed 60 to 120 days after birth. Lateral and parietal cephalograms of the crania were projected by means of a profile projector, model V-16, and enlarged 5 times. Because they reveal craniofacial-facial morphology most clearly, 15 lateral and 7 parietal points were selected. Coordinates of these points were plotted by means of an X--Y plotter system Tracings were composed as follows: For lateral cephalograms, the intersphenoid synchondrosis(S)was the zero point, and the line between S and the basion (Ba) was the abscissa. For parietal cephalograms, the occipital bone was the zero point; and the line between (0) and the upper central (Ui) was the abscissa. The masseter muscles were microsectioned for observation of changes in muscle fibers. Results 1. There were no significant differences among the body weights of the 3 groups (control, operation, and sham operation). 2. There were no significant differences in ulnar length among the 3 groups 3. Facial asymmetry and changes in occlusion were noted in the group observed 120 days after surgery. 4. Lateral cephalographic examination showed that the zygomatic arch has almost no influence on craniofacial growth and development in terms of relations among the points examined. 5. Parietal cephalographic examination showed that removal of the zygomatic arch promoted depth development and suppressed width development in the zygomatic-arch region of the side on which surgery was performed. This may indicate that the zygomatic arch acts to suppress anterior and posterior craniofacial growth and development while promoting growth and development in the lateral dimension. 6. Horizontal cytology of the masseter muscle showed atrophied masseteric tissue at the resected site of the zygomatic arch. But, because this was a partial resection, influence of muscular function is slight. And data obtained from this experiment must be considered the outcome of the removal of the zygomatic arch itself.

Animals↗
PubMed2002

Induction of cell death by sera from patients with acute brain injury as a mechanism of production of autoantibodies.

OBJECTIVE: To investigate the capacity of blood draining from the central nervous system of patients with acute brain injury to induce cell death, and to determine whether this phenomenon could be a way to induce the production of autoantibodies. METHODS: The induction of cell death of several human leukemia cell lines cultured in vitro in the presence of serum collected from the brain or the systemic circulation of patients with acute brain injury was analyzed by flow cytometry after staining with annexin V and propidium iodide. The percentages of apoptotic lymphocytes derived directly from the patients were also quantified. To investigate the mechanisms responsible for the induction of cell death, the expression of apoptosis-related molecules, as well as the effect of addition of several molecules known to interfere with apoptosis, was evaluated in the cell cultures. The presence of serum autoantibodies at the time of injury and 6 months later was studied. RESULTS: Systemic serum and, especially, serum draining from the brain lesions induced the in vitro death of the leukemia cell lines used. Moreover, there were higher percentages of ex vivo dead lymphocytes in regional blood than in systemic blood 48 hours after injury. These effects seemed to be induced by an exogenous and/or endogenous opioid, since they were blocked by the opioid antagonist, naloxone. Furthermore, such effects were mediated by an increased expression of Bax. Importantly, apoptotic Jurkat cells were bound to autoantibodies, and patients with acute brain injury produced serum autoantibodies some months after the injury. However, they did not develop a full autoimmune disease at that time. CONCLUSION: Serum factors from acute brain injuries induce cell death, both in vivo and in vitro. Apoptotic cells and, even more so, necrotic cells in acute brain injury are potential sources for autoantigen presentation that may stimulate autoimmune responses.

Acute Disease↗
PubMed2002

Initial clinical experience with infrared-reflecting skin markers in the positioning of patients treated by conformal radiotherapy for prostate cancer.

PURPOSE: To evaluate an infrared (IR) marker-based positioning system in patients receiving conformal radiotherapy for prostate cancer. METHODS AND MATERIALS: During 553 treatments, the ability of the IR system to automatically position the isocenter was recorded. Setup errors were measured by means of orthogonal verification films and compared to conventional positioning (using skin drawings and lasers) in 184 treatments. RESULTS: The standard deviation of anteroposterior (AP) and lateral setup errors was significantly reduced with IR marker positioning compared to conventional: 2 vs. 4.8 mm AP (p < 0.01) and 1.6 vs. 3.5 mm laterally (p < 0.01). Longitudinally, the difference was not significant (3.5 vs. 3.0 mm). Systematic errors were on the average smaller AP and laterally for the IR method: 4.1 vs. 7.8 mm AP (p = 0.01) and 3.1 vs. 5.6 mm lateral (p = 0.07). Longitudinally, the IR system resulted in somewhat larger systematic errors: 5.0 vs. 3.4 mm for conventional positioning (p = 0.03). The use of an off-line correction protocol, based on the average deviation measured over the first four fractions, allowed virtual elimination of systematic errors. Inability of the IR system to correctly locate the markers, leading to an executional failure, occurred in 21% of 553 fractions. CONCLUSION: IR marker-assisted patient positioning significantly improves setup accuracy along the AP and lateral axes. Executional failures need to be reduced.

Humans↗
PubMed2005

Far-lateral transcondylar approach: surgical technique and its application in neurenteric cysts of the cervicomedullary junction. Report of two cases.

Neurenteric cysts are rare benign lesions of the central nervous system that are lined by endodermal cell-derived epithelium. Although they occur mostly in the spine, they can occur intracranially, most often in the posterior fossa. Neurenteric cysts that are located in the anterior cervicomedullary junction are even rarer and often require a skull base approach for adequate resection. The authors describe two cases of neurenteric cysts arising from the cervicomedullary junction that were resected via a far-lateral transcondylar approach. They discuss the surgical approach and operative nuances involved in removing these lesions, and review the clinical presentation of neurenteric cysts in this region as well as the neuroimaging characteristics, histopathological findings, and surgical management. Intraoperative videos are presented.

Adult↗
PubMed1995

Motor neuron disease caused by mutations in superoxide dismutase 1.

A subset of pedigrees with dominant inheritance of familial amyotrophic lateral sclerosis have mutations in superoxide dismutase 1. Initial studies suggested that disease-linked mutations impaired superoxide dismutase 1 activity, which is consistent with the notion that disease results from increased oxidative injury. However, results of recent cell culture and transgenic studies demonstrate that mutant proteins retaining high levels of superoxide dismutase 1 activity cause motor neuron degeneration; elevating the level of wild-type superoxide dismutase 1 does not cause disease. These findings suggest that the familial amyotrophic lateral sclerosis phenotype may occur through other mechanisms that can now be explored in model systems.

Amyotrophic Lateral Sclerosis↗
PubMed2005

Conditional expression of a myocardium-specific transgene in zebrafish transgenic lines.

To develop the first heart-specific tetracycline (Tet)-On system in zebrafish, we constructed plasmids in which the cardiac myosin light chain 2 promoter of zebrafish was used to drive the reverse Tet-controlled transactivator (rtTA) and the green fluorescent protein (GFP) reporter gene was preceded by an rtTA-responsive element. In the zebrafish fibroblast cell-line, rtTA-M2, one of rtTA's derivatives, demonstrated the highest increase in luciferase activity upon doxycycline (Dox) induction. We then generated two germ lines of transgenic zebrafish: line T03 was derived from microinjection of a plasmid containing rtTA-M2 and a plasmid containing a responsive reporter gene, whereas line T21 was derived from microinjection of a single dual plasmid. Results showed that line T21 was superior to line T03 in terms of greater GFP intensity after induction and with of minimal leakiness before induction. The photographic images of induced GFP in the heart of F2 larvae showed that the fluorescent level of GFP was dose-responsive. The level of GFP expressed in the F3 3 days postfertilization larvae that were treated with Dox for 1 hr decreased gradually after the withdrawal of the inducer; and the fluorescent signal disappeared after 5 days. The GFP induction and reduction were also tightly controlled by Dox in the F3 adult fish from line T21. This Tet-On system developed in zebrafish shows much promise for the study of the gene function in a specific tissue at the later developmental stage.

Animals↗
PubMed1997

A high-resolution, confocal laser-scanning microscope and flash photolysis system for physiological studies.

We describe the construction of a high-resolution confocal laser-scanning microscope, and illustrate its use for studying elementary Ca2+ signalling events in cells. An avalanche photodiode module and simple optical path provide a high efficiency system for detection of fluorescence signals, allowing use of a small confocal aperture giving near diffraction-limited spatial resolution (< 300 nm lateral and < 400 nm axial). When operated in line-scan mode, the maximum temporal resolution is 1 ms, and the associated computer software allows complete flexibility to record line-scans continuously for long (minutes) periods or to obtain any desired pixel resolution in x-y scans. An independent UV irradiation system permits simultaneous photolysis of caged compounds over either a uniform, wide field (arc lamp source) or at a tightly focussed spot (frequency-tripled Nd:YAG laser). The microscope thus provides a versatile tool for optical studies of dynamic cellular processes, as well as excellent resolution for morphological studies. The confocal scanner can be added to virtually any inverted microscope for a component cost that is only a small fraction of that of comparable commercial instruments, yet offers better performance and greater versatility.

Animals↗
PubMed1989

Optimum focusing in an ultrasonic annular array imaging system using a nonspherical lens.

In this paper, a new focusing method for ultrasonic annular array imaging systems is presented. The technique minimizes the lateral resolution for a specified sidelobe suppression over the depth of interest, using a nonspherical lens for line focusing in transmit in combination with continuous dynamic focusing in receive. For this purpose, an effective analysis model is developed for calculating the impulse response of an annulus with an arbitrarily-shaped lens in the whole imaging plane. Using this analysis method, an iterative technique is then applied to obtain an optimum transmit delay profile when continuous receive focusing is employed at all imaging points along the depth of view. The delay profile is optimum in the sense that the lateral beam width is minimized under a specified sidelobe suppression at three depths of the imaging field. The continuous receive focusing is realized in a new digital focusing system which enables arbitrary control of transmit time delays and dynamic focusing in the receive mode. In the proposed system, focusing is achieved by adjusting the sampling time for each array element according to the arrival time differences among array elements for a given focal point. Experimental results show the validity of the analysis model and the optimum lens design.

Humans↗
PubMed1990

Carcinoembryonic antigen enhances metastatic potential of human colorectal carcinoma.

Patients with human colorectal carcinoma have a poor prognosis when serum carcinoembryonic antigen level exceeds 5 ng/mL. The hypothesis that carcinoembryonic antigen enhances metastasis by promoting the attachment of tumor cells to Kupffer cells and hepatocytes was tested in an experimental metastasis model in which colorectal carcinoma cells were injected into the spleens of BALB/c athymic nude mice and liver colonies counted 5 weeks later. Pretreatment with systemic injections of carcinoembryonic antigen significantly increased the metastatic potential of a poorly metastatic colorectal carcinoma cell line KM-12c, but did not induce the nonmetastatic colorectal carcinoma cell line HC 2998 to produce metastases, nor did carcinoembryonic antigen make the highly metastatic colorectal carcinoma cell line mHC 1410 more metastatic. Carcinoembryonic antigen did not stimulate proliferation of colorectal carcinoma but appeared to be a cofactor for metastasis possibly as an adhesion factor.

Animals↗
PubMed2001

Measurements of intraventricular pressure in a patient shunted from the ventricle to the internal jugular vein against the direction of blood flow (the El-Shafei shunt).

OBJECT: After demonstrating the anti-siphoning properties of a distensible tube in vitro, El-Shafei constructed a shunting system that directs CSF flow into the internal jugular vein against the flow of blood. Though clinically effective, the in vivo pressure dynamics of this type of shunt system have not been investigated. METHODS: After failure at multiple other extracranial absorptive sites, an 18-year-old woman was shunted from the lateral ventricle to the internal jugular vein against the direction of blood flow. The shunt system contained an in-line noninvasive telemonitor allowing examination of postural intracranial pressure dynamics in the awake state. This shunt system demonstrated postural pressure dynamics that were consistent with a stringent nonsiphoning shunting system. CONCLUSIONS: These observations validate the use of the El-Shafei shunt placement as a biologically nonsiphoning CSF absorptive system. In addition, the stringency of the anti-siphoning properties of the internal jugular vein open the possibility of preferentially using this shunting system in patients who clearly exhibit symptoms of shunt overdrainage.

Adolescent↗
PubMed1988

Acute infusion of chemotactic or enkephalin-analog peptides into rat cerebral ventricles: scanning and transmission electron microscopy of leukocyte immigration in vivo.

Acute infusions of the formylated chemotactic peptide formyl-methionyl-leucyl-phenylalanine-lysine (FMLPL) or enkephalin analogue (Sandoz peptide) were made to the lateral cerebral ventricle of adult male rats to examine potential cellular responses within the central nervous system (CNS). Ependymal regions lining the third ventricle atop the hypothalamus were examined using scanning and transmission electron microscopy. The formylated peptide induced a significant, primarily neutrophilic cellular response in animals sacrificed 1 h after infusion. Cells were observed within and external to neuropil blood capillaries, suggestive of emigration from vasculature in response to the peptide. In contrast, the enkephalin analogue did not induce any leukocyte cellular response within the same time frame. Earlier studies have shown a monocyte/macrophage response in the same setting to the opioid peptides beta-endorphin, and to a lesser extent, methionine enkephalin. The present findings suggest that a formylated peptide is a potent stimulus for neutrophil migration within a CNS site, while opioid peptides may be variable with respect to effectiveness on cells of the immune system within the CNS, depending upon chemical configuration.

Animals↗
PubMed2001

Early membrane estrogenic effects required for full expression of slower genomic actions in a nerve cell line.

Interpretations of steroid hormone actions as slow, nuclear, transcriptional events have frequently been seen as competing against inferences of rapid membrane actions. We have discovered conditions where membrane-limited effects potentiate later transcriptional actions in a nerve cell line. Making use of a two-pulse hormonal schedule in a transfection system, early and brief administration of conjugated, membrane-limited estradiol was necessary but not sufficient for full transcriptional potency of the second estrogen pulse. Efficacy of the first pulse depended on intact signal transduction pathways. Surprisingly, the actions of both pulses were blocked by a classical estrogen receptor (ER) antagonist. Thus, two different modes of steroid hormone action can synergize.

Alkaloids↗
PubMed2004

Osmotic properties of the sealed tubular system of toad and rat skeletal muscle.

A method was developed that allows conversion of changes in maximum Ca(2+)-dependent fluorescence of a fixed amount of fluo-3 into volume changes of the fluo-3-containing solution. This method was then applied to investigate by confocal microscopy the osmotic properties of the sealed tubular (t-) system of toad and rat mechanically skinned fibers in which a certain amount of fluo-3 was trapped. When the osmolality of the myoplasmic environment was altered by simple dilution or addition of sucrose within the range 190-638 mosmol kg(-1), the sealed t-system of toad fibers behaved almost like an ideal osmometer, changing its volume inverse proportionally to osmolality. However, increasing the osmolality above 638 to 2,550 mosmol kg(-1) caused hardly any change in t-system volume. In myoplasmic solutions made hypotonic to 128 mosmol kg(-1), a loss of Ca(2+) from the sealed t-system of toad fibers occurred, presumably through either stretch-activated cationic channels or store-operated Ca(2+) channels. In contrast to the behavior of the t-system in toad fibers, the volume of the sealed t-system of rat fibers changed little (by <20%) when the osmolality of the myoplasmic environment changed between 210 and 2,800 mosmol kg(-1). Results were also validated with calcein. Clear differences between rat and toad fibers were also found with respect to the t-system permeability for glycerol. Thus, glycerol equilibrated across the rat t-system within seconds to minutes, but was not equilibrated across the t-system of toad fibers even after 20 min. These results have broad implications for understanding osmotic properties of the t-system and reversible vacuolation in muscle fibers. Furthermore, we observed for the first time in mammalian fibers an orderly lateral shift of the t-system networks whereby t-tubule networks to the left of the Z-line crossover to become t-tubule networks to the right of the Z-line in the adjacent sarcomere (and vice versa). This orderly rearrangement can provide a pathway for longitudinal continuity of the t-system along the fiber axis.

Aniline Compounds↗
PubMed1997

The Probot--an active robot for prostate resection.

As men age, their prostates can enlarge, causing urinary difficulty. Surgery to correct this [transurethral resection of the prostate (TURP)] is a skilled and time-consuming operation requiring many repetitive motions of a cutter. A robot has been developed to perform these motions, relieving the surgeon of much of the burden of surgery. This robot has been tried both in the laboratory and later on human subjects and has proved itself capable of performing prostate resection. The Probot system consists of on-line imaging and three-dimensional prostate model construction, an appropriate surgeon-computer interface, a counterbalanced mounting frame and a computer controlled robot.

Computer Graphics↗
PubMed2005

Atrial fibrillation ablation.

Radiofrequency catheter ablation is currently used widely and successfully to treat a variety of arrhythmias, and ablation for atrial fibrillation represents the frontier of arrhythmia research. Development in many areas will offer to the electrophysiologic community a more rational and effective background upon which select patients for ablation and identify the optimal ablative strategy. Among mechanisms recognized for having a role in atrial fibrillation stay pulmonary vein focal triggers, rotor at the pulmonary vein-left atrial junction, a critical mass to sustain fibrillatory conduction and vagal ganglia. The latter represents the frontier of research as with new technologies based on magnetic resonance imaging they could be easily and specifically identified and targeted for ablation. It is fundamental that both CARTO and NavX systems are currently investigating integration with magnetic resonance imaging to reconstruct the left atrium. Furthermore a learning curve effect can be abated with the use of new systems for the remote control of the catheter such as stereotaxis. In the last decade, we empirically devised a technique that is both safe and effective for curing atrial fibrillation. Briefly, using a three-dimensional mapping system, either CARTO or NavX system, we reconstruct the left atrium and the pulmonary ostia; thereafter circumferential ablation lines are normally created starting at the lateral mitral annulus and withdrawing posterior then anterior to the left-sided pulmonary veins, passing between the left superior pulmonary vein and the left atrial appendage before completing the circumferential line on the posterior wall of the left atrium. The right pulmonary veins are isolated in a similar fashion, and then a posterior line connecting the two circumferential lines on the roof is performed to reduce the risk of macroreentrant atrial tachycardias. The endpoint for circumferential ablation is a > 70-90% reduction in voltage within the isolated regions. In this article we sought to describe critical methodological aspects of our techniques along with future implementation with new technologies and to summarize our published clinical experience on the most prestigious journals.

Atrial Fibrillation↗
PubMed1998

Polarized expression of heterologous membrane proteins transfected in a human endothelial-derived cell line.

The generation and maintenance of cell polarity in endothelial cells is poorly understood, partly because of a lack of a permanent endothelial in vitro model system. Here we evaluated the spontaneously immortalized human endothelial-derived cell line ECV304 as an in vitro model system for the study of the polarized expression of heterologous membrane proteins. Several stable ECV304 clones were generated by calcium phosphate transfection/G418 selection with cDNAs encoding membrane proteins of known cell surface distribution in the epithelial Madin Darby canine kidney (MDCK) cell line: influenza hemagglutinin and uvomorulin/E-cadherin were used as markers for the apical, respectively lateral cell membrane, the human lymphocyte surface marker CD7 served as an example of a circumferentially distributed membrane protein. Analysis of the transfected ECV304 clones using conventional and confocal immunofluorescence microscopy and immunoelectron microscopy revealed the same membrane distribution of the heterologous proteins in ECV304 cells as in MDCK cells. This polarized expression of heterologous membrane proteins in the endothelial-derived ECV304 cell line indicates efficient protein sorting/membrane trafficking mechanisms. The apical, lateral and basal cell membrane domains could be distinguished in ECV304 cells by confocal immunofluorescence microscopy. The permanent endothelial-derived ECV304 cell line may be a useful in vitro model system for the study of endothelial cell polarity.

Animals↗