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Abstract
The authors correlated neurologic features of rostral lateral pontine infarct (rLPI) with lesion location on MRI. rLPI is a motor-sensory stroke presenting as crural monoparesis or crural dominant hemiparesis and segmental superficial or deep sensory disturbances. The dorsolateral pontine base causes crural paresis without supranuclear facial palsy.
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Serum and synovial fluid concentrations of bovine chondrocalcin in dogs. Vet J 2002; 163:211-3. [PMID: 12093197 DOI: 10.1053/tvjl.2001.0645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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A case of familial amyloid polyneuropathy homozygous for the transthyretin Val30Met gene with motor-dominant sensorimotor polyneuropathy and unusual sural nerve pathological findings. ARCHIVES OF NEUROLOGY 2001; 58:1914-8. [PMID: 11709003 DOI: 10.1001/archneur.58.11.1914] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To report a case of familial amyloid polyneuropathy homozygous for the amyloidogenic transthyretin (ATTR) Val30Met gene with motor-dominant sensorimotor polyneuropathy and unusual sural nerve pathological findings. METHODS Mass spectrometry analysis and polymerase chain reaction-restricting fragment length polymorphism were performed. A right sural nerve biopsy specimen was obtained for histological investigation. SETTING Academic medical center. RESULTS A 56-year-old Japanese man living in a local town (Nakajima, Japan) in Ishikawa Prefecture, a nonendemic area of type I familial amyloidotic polyneuropathy, had vitreous amyloidosis, motor-dominant sensorimotor polyneuropathy, erectile dysfunction, and urinary incontinence. He had neither orthostatic hypotension nor indolent diarrhea. Restriction enzyme analysis with EcoT22 I of amplified DNA and mass spectrometry analysis revealed homozygosity for ATTR Val30Met. Of 8 family members, 5 were evaluated and found to be heterozygous for ATTR Val30Met; a family history found no relative with the similar neurologic disorders. The sural nerve biopsy specimen showed focal edema and an amyloid deposit in the subperineural tissue, associated with moderate loss of myelinated and unmyelinated fibers. CONCLUSIONS In addition to the findings characteristic of homozygosity for ATTR Val30Met such as vitreous amyloidosis and relatively less autonomic involvements, this case had the unique findings of motor-dominant sensorimotor polyneuropathy and unusual sural nerve biopsy specimen results.
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Abstract
We report a rare association of amyotrophic lateral sclerosis (ALS) with incidental pulmonary and muscle sarcoidosis. A 63-year-old woman presented with slowly progressive weakness and atrophy of the extremities starting from the left leg. The biopsy of a small mass in the left gastrocnemius revealed a typical sarcoid nodule. She was treated with corticosteroid for possible sarcoid neuromyopathy. In spite of the treatment, her clinical course was relentlessly progressive and she died of bulbar palsy. Autopsy revealed a loss of motor neurons in the anterior horn, vacuolar degeneration of the lateral funiculus, and noncaseating granulomas in paratracheal lymph nodes and lungs. No granulomatous lesion or cellular infiltration was found in the spinal cord.
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Abstract
The movement of the carpal bones in gripping was clarified in the giant panda (Ailuropoda melanoleuca) by means of macroscopic anatomy, computed tomography (CT) and related 3-dimensional (3-D) volume rendering techniques. In the gripping action, 3-D CT images demonstrated that the radial and 4th carpal bones largely rotate or flex to the radial and ulnar sides respectively. This indicates that these carpal bones on both sides enable the panda to flex the palm from the forearm and to grasp objects by the manipulation mechanism that includes the radial sesamoid. In the macroscopic observations, we found that the smooth articulation surfaces are enlarged between the radial carpal and the radius on the radial side, and between the 4th and ulnar carpals on the ulnar side. The panda skilfully grasps using a double pincer-like apparatus with the huge radial sesamoid and accessory carpal.
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Abstract
To evaluate the function of the constrictor urethrae of dogs that had urinary incontinence and were diagnosed as having ectopic ureter, the urethral pressure profile (UPP) was measured by means of a microchip catheter transducer. The UPPs (14.5 +/- 3.3 mmHg) of the four dogs suffering from ectopic ureter were much lower (p<0.001) than the UPPs of clinically healthy female dogs (35.3 +/- 5.7 mmHg). In the cases of ectopic ureter, it was shown that the UPP was lowered, and it was suggested that this would lead to the expression of urinary incontinence.
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Safe and efficacious dosage of flecainide acetate for treating equine atrial fibrillation. J Vet Med Sci 2000; 62:711-5. [PMID: 10945288 DOI: 10.1292/jvms.62.711] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To determine a safe and efficacious dose of flecainide acetate for treating equine atrial fibrillation (Af), the safe dosage level was determined by injecting 1, 2, or 3 mg/kg i.v. of 1% flecainide acetate solution at a rate of 0.2 mg/kg/min to five clinically healthy horses. Clinical signs and the ECG were monitored (HR, PR, QRS, and QT intervals) and blood was taken to measure the plasma flecainide concentration pre- and post-administration. No abnormal signs were observed in the 1- or 2-mg/kg groups, while agitation was observed in three of five horses in the 3-mg/kg group. The QRS, and QT intervals for the 3-mg/kg group increased significantly. The peak plasma flecainide concentrations were 1.316 +/- 358 (SD) ng/ml, 1,904 +/- 314 ng/ml, and 2,251 +/- 387 ng/ml for the 1-, 2-, and 3-mg/kg groups, respectively. To evaluate the efficacy of flecainide, Af was induced by right atrial pacing in six clinically healthy horses, and 1% flecainide acetate solution was then administered until they converted to sinus rhythm. All horses with induced Af converted. For the conversion, a total dose of 1.40 +/- 0.63 mg/kg flecainide was required, the duration of administration was 7.00 +/- 3.15 min and plasma flecainide concentration at conversion was 1,303 +/- 566 ng/ml. In conclusion, flecainide acetate is a safe and effective antiarrhythmic agent for equine Af, and the clinically effective dosage is 1 to 2 mg/kg.
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[Two cases of thalamic infarction presenting with "thalamic astasia"]. Rinsho Shinkeigaku 2000; 40:383-7. [PMID: 10967658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
We report two cases of so-called 'thalamic astasia', associated with thalamic infarction. A 76-year-old-man suddenly noted to fall down to the left side without severe hemiparesis. An MRI showed an infarction in the superolateral portion of the right thalamus. Over eight weeks, his astasia gradually disappeared. A 69-year-old-man suddenly noted inability to stand with loss of balance. He showed mild hemiparesis, hypesthesia and cerebellar signs on the right side. Although right hemiparesis was slight, he was unable to stand by himself. An MRI demonstrated an infarction in the ventrolateral to ventroposterior portion of the left thalamus. Three weeks later, his symptoms except for cerebellar ataxia remarkably disappeared. The overlapped MRI lesions of these two cases were localized in the ventrolateral thalamus, such as Vimi (nucleus ventrointermedii internus), Vci (nucleus ventrocaudalis internus), Cemc (nucleus centralis thalami magnocellularis). These lesions are so-called 'vestibular thalamic nuclei', in which fibers from vestibulocerebellum are terminated. Involvement of the thalamic connectivity explains that two patients noted inability to stand. Thus we concluded that these two patients had thalamic astasia, described by Masdeu and Gorelick.
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Cyclic GMP/cyclic GMP-dependent protein kinase system prevents excitotoxicity in an immortalized oligodendroglial cell line. J Neurochem 2000; 74:633-40. [PMID: 10646514 DOI: 10.1046/j.1471-4159.2000.740633.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Previously, we have demonstrated that excitotoxicity of oligodendrocyte-like cells (OLC), differentiated from immortalized rat O-2A progenitor cells (CG-4 cells), is prevented by cyclic AMP-elevating agents. We now report that some agents that elevate cyclic GMP prevent OLC excitotoxicity. Kainate-induced injury was prevented by cyclic GMP analogues (8-bromo-cyclic GMP and dibutyryl cyclic GMP), a guanylate cyclase activator [atrial natriuretic peptide (ANP)], and phosphodiesterase inhibitors [3-isobutyl-1-methylxanthine (IBMX), ibudilast, propentofylline, and rolipram]. When both forskolin and 8-bromo-cyclic GMP were added, kainate-induced injury was additively prevented. There was a strong positive correlation between suppression of kainate-induced Ca2+ influx and prevention of injury by these chemicals. The measurement of intracellular cyclic AMP and cyclic GMP by radioimmunoassay demonstrated the following: an increase of cyclic GMP with treatment with 8-bromo-cyclic GMP, dibutyryl cyclic GMP, and ANP; an increase of cyclic AMP with treatment with ibudilast and rolipram; and an increase of both cyclic AMP and cyclic GMP with treatment with IBMX and propentofylline. Kainate-induced Ca2+ influx was decreased by 8-(4-chlorophenylthiol)-guanosine-3',5'-monophosphate, an activator of cyclic GMP-dependent protein kinase (PKG), or okadaic acid, an inhibitor of protein phosphatases 1 and 2A. RT-PCR and westem blotting of OLC demonstrated transcription of PKG II gene and translation of PKG Ibeta mRNA, but no translation of PKG Ialpha mRNA. Therefore, we concluded that the cyclic GMP/PKG system prevents OLC excitotoxicity.
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Non-N-methyl-D-aspartate glutamate receptors mediate oxygen--glucose deprivation-induced oligodendroglial injury. Brain Res 2000; 854:207-15. [PMID: 10784123 DOI: 10.1016/s0006-8993(99)02359-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Cells of oligodendroglial lineage are susceptible to oxygen and glucose deprivation. When oligodendrocyte-like cells differentiated from CG-4-immortalized rat O-2A progenitor cells were exposed to hypoxia alone or glucose deprivation alone for 48 h, release of lactate dehydrogenase (LDH) into the culture medium did not increase. However, when cells were deprived of both oxygen and glucose for 6 or 12 h preceding reoxygenation for 2 h, LDH release increased. Adding glucose to the medium protected against cell death and increased lactate production in a concentration-dependent manner. Cell damage induced by deprivation of oxygen and glucose was prevented by calcium-free medium or by non-N-methyl-D-aspartate glutamate receptor (GluR) antagonists, such as 6-cyano-7-nitroquinoxaline-2,3-dione or LY293558, but not by the voltage-dependent calcium channel blocker, nimodipine, or by the N-methyl-D-aspartate GluR antagonist, MK-801. The glutamate concentration in the medium from cells exposed to oxygen-glucose deprivation for 12 h was 49.70+/-3.04 microM/l, which is sufficient to activate GluRs during deprivation of oxygen and glucose. Apoptotic cells detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) or Hoechst 33258 staining did not increase in cells exposed to oxygen-glucose deprivation for 12 h and subsequent reoxygenation for 2 h. No DNA laddering was detected by agarose gel electrophoresis from cells exposed to deprivation of oxygen and glucose. Neither acetyl-YVAD-CHO, an inhibitor of caspase-1-like proteases, nor acetyl-DEVD-CHO, an inhibitor of caspase-3-like proteases, prevented oxygen-glucose deprivation-induced injury. Thus, oxygen and glucose deprivation causes calcium-influx-induced necrotic cell damage in cells of oligodendroglial lineage via non-N-methyl-D-aspartate GluR channels.
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[A 54-year-old man with action myoclonus, parkinsonism and epilepsy]. NO TO SHINKEI = BRAIN AND NERVE 1999; 51:999-1007. [PMID: 10586420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
We describe 3-year clinical course of a 54-year-old Japanese man who presented with action myoclonus, parkinsonism and epilepsy. There was no family history or consanguinity. The patient was well until the age of 51 years (in 1986), when he noted slow movements, memory disturbance and left hand tremor. He was treated with anti-Parkinson drugs without any improvements. Soon thereafter, he developed a gait disturbance and generalized tonic clonic seizures. He was admitted to our service at the age of 53 years. General physical examination revealed no hepatosplenomegaly. Neurological examination showed mild dementia. Neither retinal pigmentation nor cherry red spot was noted. He was unable to walk due to marked frozen gait. His upward gaze was limited and saccadic eye movement was slow. He had action myoclonus in both upper extremities and resting tremor on the left side. He showed mild left hemiparesis. Deep tendon reflex was hyperactive in both side with extensor plantar responses. MRI demonstrated cortical atrophy, especially marked at the bilateral temporal lobes with a right side predominance. Leukocyte lysosomal enzyme activities of beta-hexosaminidase, beta-galactosidase and sialidase were within normal limits. The patient died of pneumonia on April 25, 1989. At the time of a neurological CPC, neurologists reached the clinical diagnosis of adult-type neuronal ceroid-lipofuscinosis. Postmortem examination revealed bilateral bronchopneumonia. The brain weighed 1,219 g and showed atrophy of the temporal lobes. Histological examination showed neuronal cells with swollen cytoplasm and lipofuscin-like granules throughout the CNS, including the cerebral cortex, thalamus, substantia nigra, motor nuclei of the brain stem, dentate nuclei, inferior olivary nuclei. Clarke's nuclei and anterior horn cells. Marked neuronal loss was noted in the right temporal lobe and substantia nigra. Electron micrographs of the frontal cortex revealed "fingerprint profiles" in the cytoplasm of neuronal and glial cells. Pathological findings were consistent with the diagnosis of adult-type neuronal ceroid-lipofuscinosis (Kufs' disease).
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[Apraxia of eyelid closure in a patient with progressive supranuclear palsy]. Rinsho Shinkeigaku 1999; 39:940-3. [PMID: 10614158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
We reported a 68-year-old man with progressive supranuclear palsy who present with apraxia of eyelid closure. He showed horizontal and vertical supranuclear ophthalmoplegia, neck dystonic posture, pseudobulbar palsy and subcortical dementia. He opened his eyes almost all day long except for sleeping. His spontaneous blinking was noted at less than 1 per a minute. Although he closed his eyes reflexively, he could not close his eyes by verbal command. He occasionally closed his eyelids by using both hands. The surface electromyographic (EMG) findings revealed that the frequency of frontal muscle contraction did not decrease, and rather increased during verbal command to close his eyes. The contraction frequency of orbicularis oculi muscle did not increase by the command of voluntary eyelid closure. It is suggested that abnormal contractions of frontalis and orbicularis oculi muscles which are correlated in eyelid closing and opening might contribute to the apraxia of eyelid closure.
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CT examination of the guttural pouch (auditory tube diverticulum) in Przewalski's Horse (Equus przewalskii). J Vet Med Sci 1999; 61:1019-22. [PMID: 10535506 DOI: 10.1292/jvms.61.1019] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The domestic horse (Equus caballus) have the large symmetrical guttural pouches (the auditory tube diverticulum) formed by saccate bulge of the auditory tube. In this study, CT examination was carried out in the head of Przewalski's horse (Equus przewalskii), the only true wild horse living at present. As results of the examination, Przewalski's horse possessed the large symmetrical guttural pouches divided into medial and lateral compartments by the stylohyoid bone. Moreover, the right and left guttural pouches meet each other at the median part to form a thin septum. As CT sections get close to the part of the occipital condyle, the lateral compartment disappeared, and the medial compartment gradually became small toward the base of the skull. These results indicate that the nuchal-basal part of the medial compartment is not well-developed as compared with the domestic horse.
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Abstract
The manipulation mechanism of the giant panda (Ailuropida melanoleuca) was examined by means of CT (computed tomography) and 3-dimensional (3-D) Volume Rendering techniques. In the 3-D images of the giant panda hand, not only the bones but also the muscular system was visualised. Sections of the articulated skeleton were obtained. It was demonstrated that the hand of the panda is equipped with separately moulded manipulation units as follows: (1) the radial sesamoid (RS), the radial carpal, and the first metacarpal (R-R-M) complex; and (2) the accessory carpal (AC) and the ulnar (A-U) complex. When the giant panda grasps anything, the R-R-M complex strongly flexes at the wrist joint, the RS becomes parallel with the AC, and the phalanges bend and hold the object. It is shown that the well-developed opponens pollicis and abductor pollicis brevis muscles envelop and fix the objects between the R-R-M complex and the phalanges during grasping.
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MRI examination of the masticatory muscles in the gray wolf (Canis lupus), with special reference to the M. temporalis. J Vet Med Sci 1999; 61:581-6. [PMID: 10423677 DOI: 10.1292/jvms.61.581] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We examined the head of the gray wolf (Canis lupus) using MRI methods. Although the arising surface of the M. temporalis was not so enlarged in the frontal bone, the small frontal bone did not disturb the M. temporalis from occupying the lateral space of the frontal area in the gray wolf as in the domesticated dog. In the gray wolf, it is suggested that the M. temporalis may not be well-developed in terms of size of arising area, but in the thickness of running bundles. We suggest that the dog has changed the three-dimensional plan of the M. temporalis during the domestication and that the M. temporalis has developed a large arising surface in the frontal bone and lost the thickness of belly in the frontal area in accordance with the enlargement of the frontal bone and the increase in brain size.
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[Ibudilast prevents oxygen-glucose deprivation-induced oligodendroglial injury]. NO TO SHINKEI = BRAIN AND NERVE 1999; 51:49-54. [PMID: 10065460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Previously we have demonstrated that ibudilast, which is used clinically for treating patients with asthma and cerebrovascular diseases, prevents excitotoxicity of oligodendroglial lineage mediated by Ca2+ influx via non-N-methyl-D-aspartate (NMDA) glutamate receptor (GluR) channels. We here present a finding that ibudilast prevents oxygen-glucose deprivation (OGD)-induced oligodendroglial injury. The oligodendrocyte-like cells (OLC), differentiated from the CG-4 cell line established from rat oligodendrocyte-type-2 astrocyte (O-2A) progenitor cells, were exposed to hypoxia in the absence of glucose for 12 h and subsequent reoxygenation for 2 h. Cell damage was evaluated by measuring activity of lactate dehydrogenase (LDH) released into the culture medium. OGD for 12 h induced 30 to 50% LDH release into the medium. OLC damage induced by deprivation of oxygen and glucose was prevented by ibudilast at concentrations of > or = 50 microM. The protection given by ibudilast against OGD-induced injury was enhanced by prostacyclin (PGI2). OGD-induced OLC injury was prevented by 6-cyano-7-nitroquinoxaline-2, 3-dione (CNQX), an inhibitor of non-NMDA GluR or deprivation of Ca2+ from culture medium. While ibudilast increased intracellular cAMP at concentrations of > or = 10 microM, at least 100 microM concentrations were needed to increase intracellular cGMP. Therefore, we concluded that ibudilast prevented OGD-induced oligodendroglial injury possibly by increasing intracellular cAMP which modulates Ca2+ influx via non-NMDA GluR channels.
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Intrinsic atrioventricular conductive function in horses with a second degree atrioventricular block. J Vet Med Sci 1997; 59:149-51. [PMID: 9101472 DOI: 10.1292/jvms.59.149] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The atrioventricular (AV) conductive functions were investigated before and after the pharmacological autonomic nervous blockade (PAB) through the electrophysiological study on six horses (AV block group) in which the dropped beats occurred more frequently (over 200 beats/24 hr) and on five horses (control group) in which the dropped beats occurred sporadically (under 200 beats/24 hr) or in which the arrhythmias were not recognized at all on the long-term electrocardiogram. As a result, AV conductivity, conduction time and refractoriness in the AV block group were lower, longer and higher, respectively, than those in the control group even after PAB. These results indicate the intrinsic AV conductive functions in the AV block group were withdrawing than in the control group.
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Abstract
Although the horse is considered an elite athlete with a specific VO2max some 2-4 times higher than man, maximal O2 transport is compromised both by moderately severe arterial desaturation and by failure to extract all O2 from blood perfusing exercising muscle. This prompted the present study to ascertain whether correction of arterial desaturation would proportionally augment VO2max and, if so, would O2 extraction behave in a manner predicted by diffusional transport limitation. Six two year old thoroughbreds were exercised to VO2max on a treadmill each on three separate occasions breathing gases of FIO2 = 0.15, 0.21 and 0.35, each used once in balanced order. VO2, ventilation, arterial and pulmonary arterial blood gases, pressures and lactate levels were measured both submaximally and maximally at each FIO2 and cardiac output was computed by mass balance for O2. At FIO2 = 0.21, VO2max = 143.9 +/- 4.8 ml kg-1 min-1, arterial saturation (SaO2) was 81.6 +/- 3.3% while venous PO2 (PvO2) was 15.3 +/- 1.4 Torr. At FIO2 = 0.35, VO2max was 172.6 +/- 8.2 ml kg-1 min-1, SaO2 reached 97.4 +/- 0.4% and PvO2 was 23.4 +/- 0.7 Torr. VO2max at FIO2 = 0.15 was 109.8 +/- 4.1 ml kg-1 min-1, SaO2 fell to 68.1 +/- 2.5% and PvO2 was 10.6 +/- 1.0 Torr, all changes being significant, p < 0.01. As FIO2 was varied, VO2max changed proportionally to calculated mean capillary Po2 as well as to total O2 delivery. These data confirm substantial O2 supply dependence of VO2max in the horse, and in such a manner as to be consistent with the hypothesis of combined diffusive and convective transport limitation within muscle.
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Hypoxic helium breathing does not reduce alveolar-arterial PO2 difference in the horse. RESPIRATION PHYSIOLOGY 1995; 100:253-60. [PMID: 7481115 DOI: 10.1016/0034-5687(94)00138-p] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In a previous study we evaluated the mechanism of alveolar-arterial PO2 (AaPO2) reduction when nitrogen is replaced with helium in normoxia (FIO2 = 0.21). The reduction in AaPO2 was not due to changes in VA/Q inequality, pulmonary O2 diffusing capacity, or cardiac output, but to more complete diffusion equilibration as a consequence of the higher ventilation and thus PAO2 (which reduced the average slope of the hemoglobin O2 dissociation curve (ODC), and thus enhanced diffusive equilibration). We hypothesized that hypoxic He/O2 breathing in contrast would not reduce the AaPO2 because PAO2 and PaO2, although higher with He than N2, would remain constrained to the linear region of the ODC. Breathing hypoxic gas mixtures did constrain the PAO2 to the linear region of the ODC, even when PAO2 was increased by He/O2 breathing. Thus, the average slope of the ODC did not change when He replaced N2 and this explains the lack of change in AaPO2, as hypothesized.
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Abstract
Exercise in normal human subjects causes deterioration of matching of ventilation to blood flow in the lungs, but only in about 50% of those examined. A previous study (Wagner et al. 1989) of 5 horses showed no significant worsening of ventilation/blood flow (VA/Q) relationships during heavy exercise as determined by multiple inert gas elimination technique (MIGET). Because of the small number of horses in that study and the 50% human incidence of exercise induced VA/Q mismatch, we studied an additional 6 Thoroughbreds, comparing VA/Q relationships at the walk (1.4 m/s, 0 degrees incline) and during galloping (9.6 +/- 0.3 m/s, 7% incline). Such data were collected under 4 different conditions wherein inspired gas was 1) air, 2) 21% O2 in helium, 3) 15% O2 in N2 and 4) 15% O2 in helium. Each horse exercised 4 times (morning and afternoon of 2 days, with inspired gas conditions randomised). There was a small but significant increase in VA/Q mismatch (similar under all 4 conditions). The second moment of the VA/Q distribution (determined by the MIGET) increased significantly (P < 0.01) from 0.31 +/- 0.01 at the walk to 0.38 +/- 0.02 during gallop. This increase however is small: 0.38 is well within the range of this parameter for normal human subjects (where the 95% upper confidence limit is 0.60). This study shows that a small amount of exercise induced VA/Q mismatch can occur in the horse as in man, but the mechanism remains to be elucidated and its clinical significance remains to be established.(ABSTRACT TRUNCATED AT 250 WORDS)
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Mechanism of reduction in alveolar-arterial PO2 difference by helium breathing in the exercising horse. J Appl Physiol (1985) 1994; 76:2794-801. [PMID: 7928913 DOI: 10.1152/jappl.1994.76.6.2794] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Previous work has shown that replacing N2 in air with He at the same inspired O2 fraction reduces the exercise-induced alveolar-arterial PO2 difference (AaPO2) in horses but has provided no mechanism explaining this effect. We sought to distinguish among possible causes by using the multiple inert gas elimination technique. Six horses were studied on a high-speed treadmill while they breathed either ambient air or normoxic He-O2. O2 uptake reached 138.0 ml.min-1.kg-1 and was not affected by He-O2. Temperature-corrected arterial PO2 was 76.7 Torr (air) and 86.9 Torr (He-O2) (P < 0.01). Corresponding AaPO2 was 22.3 and 15.9 Torr, respectively (P < 0.01). Mean AaPO2 predicted from ventilation-perfusion inequality did not change with He-O2 (12.7 Torr with air and 11.9 Torr with He-O2). Mean arterial PCO2 was 50.1 Torr with air and 44.1 Torr with He-O2 (P < 0.01); minute ventilation and tidal volume were correspondingly higher by 140 l/min and 1.0 liter, respectively, with He-O2. Pulmonary O2 diffusing capacity, cardiac output, and all ventilation-perfusion dispersion indexes did not change with He-O2. Intrapulmonary shunt was insignificant. Higher ventilation with He-O2 explained only approximately 4 Torr of the 10-Torr rise observed in arterial PO2. The remainder (and the corresponding fall in AaPO2) was due to more complete diffusion equilibration as a consequence of the higher minute ventilation and thus alveolar PO2, which reduced the average slope of the O2 dissociation curve, thereby increasing the ratio of diffusive to perfusive conductance.
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40 HEMODYNAMIC CONSEQUENCES OF SPLENECTOMY IN THE HORSE. Med Sci Sports Exerc 1993. [DOI: 10.1249/00005768-199305001-00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
An open-reading frame designated 1R1, on DNA component 1 of bean golden mosaic geminivirus (BGMV), has been identified as the coat protein gene. A DraI restriction fragment of BGMV DNA1 that includes 1R1 was inserted into the SmaI pKK223-3 expression vector. The 32 kD protein expressed in Escherichia coli cells reacted with antibodies to the BGMV capsid polypeptide and behaved identically to purified capsid protein in western blots.
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Clinical and endocrinological features of statistical clusters of women with climacteric symptoms. TOHOKU J EXP MED 1985; 146:59-68. [PMID: 3927516 DOI: 10.1620/tjem.146.59] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Clinical and endocrinological features of women with climacteric symptoms, who were clustered by means of factor analysis and cluster analysis, were evaluated as to serum concentrations of estradiol, progesterone, follicle-stimulating hormone and luteinizing hormone, and also as to mean ages as well as a rate of premenopausal women or that of postmenopausal women against all women in each one of the clusters. Comparison of these parameters among these clusters indicated, with statistical significance, that vasomotor symptoms, neurotic symptoms, and depressive state of the climacteric women are endocrinologically characterized by a depressed level of serum estrogen, relatively high level of serum estrogen, and an elevation of serum gonadotropin, particularly of luteinizing hormone, respectively.
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Abstract
With a view to evaluating pituitary-ovarian relationships in women approaching the menopause, serial determinations of basal body temperature (BBT) and of serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and oestradiol were performed in 5 pre-menopausal and 9 young women throughout a complete menstrual cycle. The hormone levels in the early follicular phase and on LH peak-days in the two groups were then compared. In the pre-menopausal group the age range was 43-45 yr and the length of the menstrual cycles investigated varied from 30-56 days, the BBT curves being biphasic. Two pre-menopausal women demonstrated concentrations of FSH and LH that were higher than those in the young women, even though their serum oestradiol levels in the early follicular phase remained within the upper and lower mean values observed in the young women. This finding confirmed that, in addition to reduced ovarian oestrogen secretion, another, as yet unknown, factor must exist, which can produce a rise in serum gonadotrophin levels in women approaching the menopause.
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[The correlation between climacteric symptoms and plasma levels of catecholamines (author's transl)]. NIHON NAIBUNPI GAKKAI ZASSHI 1980; 56:993-9. [PMID: 7461226 DOI: 10.1507/endocrine1927.56.7_993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Although climacteric symptoms, particularly, vasomotor symptoms such as hot flushes, have been suggested to correlate with depletion of ovarian estrogen secretion, its precise mechanism to producing these symptoms has still remained unknown. On the other hand, catecholamines have been presumed to be related to an onset of the climacteric symptoms. This study was carried out to elucidate the correlation between the climacteric symptoms and plasma levels of catecholamines. Thirty-eight women complaining of climacteric symptoms were studied. These subjects were evaluated for their symptoms and the severity of the symptoms was expressed in numerical figure, 0 to 3, according to its degrees: none, slight, moderate, and marked, respectively. At the same time venous blood samples were drawn to determine the plasma levels of catecholamines, using an Renzini's fluorimetric assay method improved by Miura. Eventually, a correlation between severities of the symptoms and plasma catecholamines was made. Plasma epinephrine levels were found to be elevated as the severity of the hot flush progressed from none to marked. No symptoms other than hot flush showed such significant correlation with plasma epinephrine or norepinephrine levels. This result suggests that the onset of hot flush is closely related with an increased activity of the adrenomedullary sympathetic nervous system.
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Correlation between climacteric symptoms and serum levels of estradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone. Am J Obstet Gynecol 1977; 129:65-7. [PMID: 900171 DOI: 10.1016/0002-9378(77)90822-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Correlation between the climacteric symptoms and serum levels of estradiol. progesterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) was studied in 191 premenopausal and postmenopausal women. Significant correlation was obtained between the climacteric symptoms represented by the menopausal index of Kupperman and associates and serum levels of estradiol as well as LH in a subgroup of the premenopausal women, ages 35 to 39 years. The symptoms were shown to be significantly related in serum levels of LH and inversely related to estradiol. These results confirmed that climacteric symptoms, at least in premenopausal women 35 to 39 years of age, could result from a low output of ovarian estrogen and a high production of pituitary gonadotropin.
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[Relationship between general malaise of women in or around the time of menopause and serum estradiol, FSH, and LH levels]. HORUMON TO RINSHO. CLINICAL ENDOCRINOLOGY 1977; 25:903-6. [PMID: 912935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Acute effects of intravenous infusion of conjugated estrogen on serum levels of LH and FSH in post-menopausal and castrated women. TOHOKU J EXP MED 1977; 121:315-9. [PMID: 194359 DOI: 10.1620/tjem.121.315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In order to quantify the changes of feed-back effect of estrogen on the release of pituitary gonadotropin which is regulated by the hypothalamic-pituitary-ovarian system, the responses of LH and FSH to the intravenous infusion of 20 mg of conjugated estrogen were studied in 49 post-menopausal and 20 castrated women. In the group of women within 1 year after menopause, serum LH levels were elevated following the infusion of the conjugated estrogen. The responses of serum LH and FSH levels were different between post-menopausal and castrated women. The data indicated that the difference between the two groups was probably due to the difference of secrection patterns of the gonadotropins in post-menopausal and castrated women.
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Abstract
Serum estradiol, progesterone, LH and FSH were concomitantly measured by radioimmunoassay in pre- and post-menopausal women in an attempt to study hormonal changes occurring in menopause. The level of serum estradiol in post-menopausal women was maintained at the same level as in pre-menopausal stage within one year after menopause and thereafter began to decrease to the senile minimal level. On the other hand, the mean serum levels of FSH and LH were elevated gradually after menopause. At the conclusion of this study, it was suggested that the key point of the mechanism of menopause may exist not only in the depletion of ovarian function but in the change of the regulatory mechanism of LH and FSH secretion by aging.
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Changes in hypophysio-ovarian endocrinological function of post-menopausal and castrated women. TOHOKU J EXP MED 1976; 120:19-24. [PMID: 960105 DOI: 10.1620/tjem.120.19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The serum levels of estradiol, progesterone, LH and FSH were determined by radioimmunoassay in post-menopausal and castrated women and the data obtained at the same periods after menopause and castration were compared. The serum levels of estradiol and progesterone in post-menopausal women within 1 year after menopause were higher than those of castrated women. The result suggested that ovarian function was indeed depressed in the post-menopausal women but was still preserved for 1 to 2 years after menopause. In the post-menopausal women, the levels of serum LH and FSH rose gradually to reach a peak at 1 to 3 years after menopause, when the production of ovarian sex steroid hormones presumably ceased. On the contrary, the serum LH and FSH levels of castrated women began to decrease gradually 4 to 9 years after castration. It is highly suggestive from these findings that a negative feedback mechanism is elicited by ageing.
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