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J H Wood

Publications and source records attributed to J H Wood.

At least 19 recordsLinked to original sources
PubMed1991

Experimental isovolemic haemodilution-induced augmentation of carotid blood flow and oxygen transport through graded carotid stenoses.

The effect of haemodilution without volume expansion (isovolemic haemodilution) was assessed with respect to blood flow and oxygen transport across stenotic lesions of progressive severity in the dog carotid artery. As the mean haematocrit (Hct) was reduced from 40 +/- 1% (+/- SEM) to 32 +/- 0% (p less than 0.001), reductions in vascular resistance were significant across the 90% (p less than 0.001) and 95% (p less than 0.0003) relative carotid stenoses. Isovolemic haemodilution reduced fresh blood viscosity significantly by 27 +/- 3% (p less than 0.001) and 42 +/- 4% (p less than 0.001) at the low shear rates of 10 sec-1 and 1 sec-1 which are typical of low-flow states. Following a 20% reduction in Hct 30 to 35% increase (p less 0.001) in carotid blood flow occurred at non-critical degrees of stenosis while a mean 83% increase (p less than 0.001) occurred at the highly critical 95% relative stenosis. Oxygen transport after a 22% decrease in blood haemoglobin was significantly increased by 28% (p less than 0.01) at the 95% relative stenosis level. These data provide a physiologic rationale for the beneficial effects of haemodilution in acute cerebral ischaemia, cerebral vasospasm and cerebral revascularization or carotid endarterectomy.

Animals↗
PubMed1990

LC determination of the diastereomers of 1-(beta-D-glucopyranosyl)phenobarbital in human urine.

The "product enantioselectivity" associated with the urinary excretion of the phenobarbital N-glucoside conjugates has not been determined previously. A liquid chromatography method using gradient elution was developed for quantifying both phenobarbital N-glucoside conjugates, phenobarbital, and p-hydroxyphenobarbital. Following a single oral dose of phenobarbital to male Caucasian and Oriental subjects, both phenobarbital N-glucoside conjugates were observed in the urine. In seven subjects, 3.3-10.6% of the phenobarbital dose was detected as a single phenobarbital N-glucoside (S configuration at the C-5 position of the barbiturate ring). The other phenobarbital N-glucoside diastereomer accounted for less than 1.5% of the phenobarbital dose. The urinary excretion of the major phenobarbital N-glucoside diastereomer paralleled the urinary excretion of phenobarbital and was comparable in both Caucasian and Oriental subjects. These results indicate a pronounced selectivity for the formation and/or urinary excretion of the phenobarbital N-glucosides.

Asian People↗
PubMed1989

High-performance liquid chromatographic method for the determination of salicylic acid and its metabolites in urine by direct injection.

A direct injection method has been developed for the determination of salicylic acid and its metabolites in urine. Urine samples are treated with hydroxylamine to convert salicyl acyl glucuronide to salicylhydroxamic acid, which can be accurately quantitated by direct injection into a high-performance liquid chromatographic system along with salicylic acid, gentisic acid and salicyluric acid. Salicyl phenolic glucuronide is quantitated by difference after hydrochloric acid hydrolysis at 65 degrees C with no loss of salicylic acid by sublimation or hydrolytic loss of salicyluric acid. This method has been applied to urine samples from human subjects and the results are discussed.

Chromatography, High Pressure Liquid↗
PubMed1986

Management of spasmodic torticollis.

Based on a review of the literature, the management of spasmodic torticollis may begin with the conservative measures of pharmacotherapy, sensory feedback, or percutaneous dorsal column stimulation. Approximately 50% of patients will benefit from an adequate trial of these modalities. With particularly resistant and disabling torticollis, the ablative procedures of microsurgical cervical rhizotomy or stereotaxic thalamotomy have offered significant relief in about 74% and 56%, respectively, of properly selected cases. Nevertheless, the variability in the duration of response to all forms of therapy has made the treatment of spasmodic torticollis a difficult and often frustrating undertaking.

Electric Stimulation Therapy↗
PubMed1986

Pathophysiology of cerebrospinal fluid in head injury: Part 1. Pathological changes in cerebrospinal fluid solute composition after traumatic injury.

After head injury, many complex neurochemical events occur locally, at the site of initial injury, and globally, as a result of secondary phenomena. Neurochemical alterations in the cerebrospinal fluid after injury can be utilized to reflect these events. The authors review the role of the cerebrospinal fluid in the treatment of head injury as it relates to the diagnosis, prognosis, and further elucidation of the pathophysiological manifestations of head injury at the cellular and biochemical level.

Acetylcholine↗
PubMed1986

Pathophysiology of cerebrospinal fluid in head injury: Part 2. Biochemical markers for central nervous system trauma.

Many substances are released into the cerebrospinal fluid after head injury. The study of these substances and their relationship to the severity and outcome of head trauma has lead to the search for biochemical markers to aid in the quantification of the severity of the lesion and serve as a prognostic guide. The authors review the potential usefulness of biochemical markers, qualities of an ideal marker, and several potential enzymes that may be utilized as markers in central nervous system trauma.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1985

Physiological neuroendocrinology of peptides, steroids and other hormones in cerebrospinal fluid.

Cerebrospinal fluid acts as a conduit in neuroendocrine regulation. Valid assessment of normal cerebrospinal fluid levels of peptides, steroids and other hormones requires clarification of reference concentrations in control patients and normal volunteers. Awareness of factors which may alter neuronal activity and, in turn, the relative composition of cerebrospinal fluid constituents is essential to the accurate sampling and hormonal analysis of cerebrospinal fluid.

Angiotensin II↗
PubMed1985

Primary lymphoma of the central nervous system diagnosed by computed tomographic scan-directed needle biopsy with a frozen section immunoperoxidase technique.

Primary lymphoma of the central nervous system is an uncommon neoplasm that requires definitive diagnosis because it is potentially treatable. We report a case in which the diagnosis of lymphoma was unsuspected and was made by needle biopsy with computed tomographic scan direction. A frozen section immunoperoxidase technique demonstrated monoclonality. When combined with a compatible morphological appearance, this confirmed the diagnosis of lymphoma. This case demonstrates the importance of this immunochemical method in the rapid diagnosis of central nervous system lymphomas.

Adult↗
PubMed1979

Cerebral abscesses produced by bacterial implantation and septic embolisation in primates.

The degree of brain abscess encapsulation is positively related to surgical mortality and methods to enhance capsule wall formation, therefore, have therapeutic relevance. Two primate models are described which may be useful in the investigation of encapsulation of traumatic and metastatic brain abscesses. Direct intracerebral inoculation induces abscesses displaying more prominent inflammatory responses and encapsulation than does septic embolisation, despite similar abscess age and size. Cerebral ischaemia surrounding metastatic suppurative foci may retard capsule wall formation.

Animals↗
PubMed1979

CSF HVA and 5-HIAA.

Explore the source record for details and available documents.

Homovanillic Acid↗
PubMed1979

Low cerebrospinal fluid gamma-aminobutyric acid content in seizure patients.

Gamma-Aminobutyric acid (GABA) has been implicated in the neurochemistry of epilepsy. Lumbar cerebrospinal fluid (CSF) GABA concentrations determined using an ion-exchange fluorometric assay reflect brain GABA content. The mean lumbar CSF GABA concentration among 21 medicated patients with intractable seizures was significantly lower (p less than 0.001) than that of 20 unmedicated normal volunteers. Patients with generalized tonic-clonic (grand mal) and complex partial (psychomotor) seizures had significantly lower (p less than 0.05) CSF GABA concentrations than those with simple partial (focal sensory/motor) seizures. Although lumbar CSF GABA levels in our seizure patients did not significantly correlate with serum concentrations of phenytoin, phenobarbital, or primidone, additional study of medication-free epileptic patients may be required to evaluate the possibility of anticonvulsant-drug-induced CSF GABA alterations.

Adult↗
PubMed1979

CSF calcium: clinical correlates in affective illness and schizophrenia.

In a study of electrolytes in lumbar cerebrospinal fluid (csf) from psychiatric patients, the authors found a positive correlation between calcium concentration and symptom severity in hospitalized depressed patients. CSF calcium levels tended to decrease as patients improved. In four rapidly cycling patients, CSF calcium was higher during depression than during mania. Mean CSF calcium for the depressed patients as a group was not significantly different from neurological controls or other psychiatric patients. Symptom remission from acute psychosis in schizophrenic patients was accompanied by a significant increase in CSF calcium concentration. These findings are discussed in relationship to calcium-induced alterations in neuronal and physiological excitability.

Bipolar Disorder↗
PubMed1978

Tetracycline. Another example of generic bioinequivalence.

Because of the Food and Drug Administration batch certification assurances, state government systems generally purchase antibiotics from the lowest bidder. A tetracycline hydrochloride tablet purchased in this manner is shown to be inferior to the innovator capsule product.

Biological Availability↗