Search PubMed⌕ Search

Biomedical subjects

J J Townsend

Publications and source records attributed to J J Townsend.

At least 73 records · Page 4Linked to original sources
PubMed1979

Morphology of central nervous system disease in immunosuppressed mice after peripheral herpes simplex virus inoculation. Trigeminal root entry zone.

Inoculation of mice and rabbits on the cornea with herpes simplex type 1 virus has been shown to cause an ascending infection of the trigeminal nerve, ganglion, and descending tract within the brainstem (2, 3, 7). A discrete, destructive, and primarily demyelinative lesion is seen on the central nervous system side of the trigeminal root entry zone 5 to 8 days after infection (8, 15, 16). This study, utilizing Swiss mice, demonstrated that immunosuppression with cyclophosphamide prior to infection with herpes simplex type virus causes a marked reduction of the mononuclear infiltrate within the central nervous system and a significant decrease in myelin destruction when compared with the infected, nonimmunosuppressed control animals. The content of virus in the brainstem was similar in both groups by day 8 as were the neutralizing antibody titers to herpes simplex type 1 virus. These results suggest that the cellular response plays a definitive role in the destruction of central nervous system tissue after peripheral infection with herpes simplex type 1 virus.

Animals↗
PubMed1978

Central nervous system susceptibility to herpes simplex infection.

Four days after inoculation of herpes simplex virus (HSV) on the rabbit cornea, distinctive and reproducible lesions appear in the trigeminal root entry zone. These viral lesions, situated in the central nervous system (CNS) portion of the root, consist of severe myelin destruction accompanied by mononuclear cell infiltration and partial sparing of axons. Immunofluorescent study demonstrated abundant viral antigen, and by electron microscopy viral nucleocapsids were found to be numerous within astrocytes and were rarely found in other cell types. In contrast, the adjacent peripheral nervous system (PNS) tissue appears unaffected by the presence of virus. The mechanism for this marked difference in response of the central nervous system and the peripheral nervous system may depend upon the susceptibility of astrocytes to viral infection and replication. The selective nature of the lesion provides an easily reproducible model for further investigation of the response of nervous system tissue to HSV.

Animals↗
PubMed1978

Histological changes in skeletal muscle after temporary independent occlusion of arterial and venous supply.

In both replantation and transplantation, circulation is restored to ischemic muscle by vascular anastomoses. As a result, the length of time that skeletal muscle will endure ischemia is important to know clinically. Using microsurgical techniques, we shut off the blood supply to the quadriceps femoris muscle in adult Wistar rats--by occluding the artery, the vein, or both for varying time intervals. The muscle was maintained in the animal for 48 hours, and then examined histologically. Our results indicate that the period of warm ischemia should be limited to about one hour, because a longer period of arterial ischemia produces severe histological changes in muscle. The limiting factor seems to be the arterial, rather than the venous supply. The possibility of muscle regeneration after such ischemic insults was not investigated.

Animals↗
PubMed1977

Radiation therapy for pineal tumors and suprasellar germinomas.

Data on all patients with pineal body tumors and suprasellar germinomas seen at the University of California--San Francisco over a 25-year period were reviewed. Of 19 patients treated, 15 are still alive. Although treatment techniques varied, all patients received irradiation to the primary tumor site but not to the spinal cord. The tumor dose ranged from 4,000 to 5,500 rads using megavoltage equipment. The authors recommended a dose of 4,500-5,000 rads given over a period of five to six weeks.

Adolescent↗
PubMed1977

A metastasizing ependymoma of the cauda equina. Case report.

A case is described in which a metastatic ependymoma of the cauda equina recurred after prolonged remission. Similarities to five previously reported cases are discussed, with emphasis on the mode of metastasis. Factors most closely associated with distant metastases include early onset, numerous local operations, long survival, and massive local recurrence at the time of distant metastases.

Adult↗
PubMed1976

Myoclonus in Alzheimer disease. A confusing sign.

Myoclonus in association with dementia of later adult life has been considered almost pathognomonic of Creutzfeldt-Jakob disease. However, myoclonus may also be seen with Alzheimer disease, and when the myoclonus occurs as an early manifestation of Alzheimer disease, distinction from Creutzfeldt-Jakob disease may prove difficult.

Aged↗
PubMed1976

The treatment of meningiomas in childhood.

Thirteen cases of meningiomas in the pediatric age group seen at the University of California are reviewed. Four of these patients are alive; one had complete surgical resection of tumor and three had subtotal resection followed by irradiation, with total tumor doses of 4500 to 5500 rads. On the basis of these data, together with our total experience in the treatment of 188 patients with meningiomas, we conclude that patients who have complete surgical resection need no further treatment but patients who have subtotal removal may have recurrences delayed or prevented by the addition of postoperative irradiation to their therapeutic regimens.

Adolescent↗
PubMed1976

The neuropathology of progressive rubella panencephalitis of late onset.

The clinicopathological changes in a case of progressive rubella panencephalitis of late onset have been presented. The prominent pathological findings in the brain included diffuse destruction of white matter with perivascular inflammatory cells and gliosis, moderate neuronal loss, numerous amorphous vascular deposits in the white matter and severe generalized cerebellar atrophy. These changes are compared and contrasted with those found in congenital rubella and other latent viral illnesses.

Adult↗
PubMed1976

Cerebellar glioblastoma multiforme in an adult.

One of the few well documented cases of cerebellar glioblastoma multiforme in an adult is reported. In addition, to our knowledge, it is the first reported case in which the angiographic, pneumoencephalographic, nuclear scan and CAT data have been correlated. In this case the CAT scan proved the most sensitive in the demonstration of tumor.

Age Factors↗
PubMed1975

Progressive rubella panencephalitis. Late onset after congenital rubella.

In children with congenital rubella infection the deficits remain stable; neurologic deterioration after the first few years of life is not believed to occur. We have encountered three patients with a definite or presumptive diagnosis of congenital rubella, in whom a progressive neurologic illness developed that began in the second decade and was characterized by spasticity, ataxia, intellectual deterioration, and seizures. High antibody titers to rubella virus in serum and spinal fluid were present in two, and all had increased cerebrospinal-fluid protein and gamma globulin. Extensive attempts to recover a virus from brain and body fluids were unsuccessful. The brains of two patients showed a widespread, progressive, subacute panencephalitis mainly affecting white matter. These data suggest that rubella virus may be a cause of progressive panencephalitis.

Adolescent↗
PubMed1975

Acquired toxoplasmosis. A neglected cause of treatable nervous system disease.

The neurological manifestations of six cases of acquired central nervous system toxoplasmosis are compared with the 39 well-documented cases from the literature. Half of the patients had underlying systemic diseases (18 malignant neoplasms, two renal transplants, three collagen vascular diseases) treated with intensive immunosuppressive therapy. The remainder had primary toxoplasmosis. Three major neurological patterns were seen: (1) diffuse encephalopathy with or without seizures, (2) meningoencephalitis, and (3) singular or multiple progressive mass lesions. Routine neurological diagnostic studies were not helpful. The Sabin-Feldman dye test or IgM indirect fluorescent antibody test or both were effective in confirming the diagnosis. Twenty-seven patients died without a clinical diagnosis of toxoplasmosis. The diagnosis was made terminally in four additional patients. Thirteen of fourteen patients who received a full course of sulfadiazine or pyrimethamine or both did well. Toxoplasmosis should be considered in the immunosuppressed patient who appears with neurological involvement.

Adult↗
PubMed1975

Unilateral megalencephaly: hamartoma or neoplasm?

The clinical and pathologic findings in three cases of unilateral megalencephaly, showing a spectrum of mild to severe involvement, are presented. The first case demonstrated an increase in neuronal size and mild gliosis and is contrasted with the second and third cases, which showed a progressive enlargement and bizarre appearance of neurons associated with an increase in number and size of astrocytes. The relationship of these cases to developmental and neoplastic disease in the brain is discussed.

Brain↗
PubMedDate not supplied

Recurrent laryngeal nerve histopathology in spastic dysphonia: a preliminary study.

Spastic dysphonia is a severe voice disorder ordinarily described as psychogenic. Organic-neurologic changes secondary to central or peripheral nervous system involvement have also been postulated and led recently to the surgical treatment of spastic dysphonia by unilateral section of the recurrent laryngeal nerve (RLN). This study reports the histologic findings from these resections of the RLN from patients with an average 9.5 years duration of spastic dysphonia. Thirty percent of the RLNs examined demonstrated significant abnormalities as compared to age-matched controls. Although no reactive changes were noted by light microscopy, groups of fibers which did not stain for myelin or axons were found in RLNs from patients with spastic dysphonia. A preliminary ultrastructural study of these areas in one RLN revealed sheets of unmyelinated axons. These findings suggest an organic basis for spastic dysphonia at least in some patients.

Adult↗