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Biomedical subjects

C Oster

Publications and source records attributed to C Oster.

At least 19 recordsLinked to original sources
PubMed1995

Human immunodeficiency virus type 1 cellular RNA load and splicing patterns predict disease progression in a longitudinally studied cohort.

We report the results of a longitudinal study of RNA splicing patterns in 31 early-stage human immunodeficiency virus disease patients with an average follow-up time of 3 years. Eighteen patients showed no evidence for disease progression, whereas 13 patients either showed a > or = 50% reduction in baseline CD4 count or developed opportunistic infections. Levels of unspliced, tat, rev, and nef mRNAs in peripheral blood mononuclear cells were measured by a reverse transcriptase-quantitative, competitive PCR assay. Viral RNA was detected in all patients at all time points. All 13 rapid progressors had viral RNA loads that were > or = 1 log unit greater than those of the slow progressors. In addition, seven of the rapid progressors showed a reduction of more than threefold in the ratio of spliced to unspliced RNA over the 3 years of follow-up. Conversely, two slow progressors with intermediate levels of viral RNA showed no splicing shift. These results confirm earlier observations that viral RNA is uniformly expressed in early-stage patients. We further show that cellular RNA viral load is predictive of disease progression. Importantly, the shift from a predominately spliced or regulatory viral mRNA pattern to a predominately unspliced pattern both is associated with disease progression and adds predictive utility to measurement of either RNA class alone.

AIDS Vaccines↗
PubMed1993

The prognostic utility of delayed-type hypersensitivity skin testing in the evaluation of HIV-infected patients. Military Medical Consortium for Applied Retroviral Research.

Many reagents and techniques have been used for delayed-type hypersensitivity (DTH) skin testing in the evaluation of HIV-infected patients, resulting in varied interpretation of the utility of DTH skin testing in this population. We report the development of a simple algorithm for selection of DTH antigens and the clinical relevance of DTH skin testing in HIV disease. Antigens and concentrations for testing were first evaluated in a demographically matched, HIV-negative, immunologically healthy population. The testing scheme was then applied to the HIV population of interest for 5 years at several clinical sites. The antigens and concentrations selected resulted in 100% reactivity to two or more antigens in the HIV-negative cohort. Anergy is thus a distinct immunologic abnormality. Although some correlation (r2 = 0.6) of skin test reactivity and CD4 cell count was found in a cohort of HIV-infected individuals, anergy was found to be independently predictive of the development of symptomatic late-stage disease (Walter Reed Stage 6), AIDS, or death. This stepwise evaluation of skin testing and reagents has led to the modification of the skin testing protocol by defining the minimum number of antigens required and establishing the independent prognostic role of DTH skin testing in the evaluation of HIV-infected patients. The addition of mumps (40 CFU/ml), tetanus (1:10), and candida (1:10) to the purified protein derivative (PPD) skin test provides the critical controls to evaluate the status of PPD skin test in HIV-infected individuals as well as to provide a useful and prognostic clinical immunology evaluation.

Adult↗
PubMed1990

"Bounces": an analysis of short-term return visits to a public hospital emergency department.

From July through September 1987, our emergency department registered 17,214 patients, of whom 569 (3%) returned within two days of initial registration. Cases were reviewed to identify factors associated with return visits. Patient-related factors were responsible for a majority of repeat visits (267 cases, 53%). Illness-related factors, particularly evolution of disease under close outpatient observation, prompted return in 68 cases (13%). An additional 60 patients (12%) returned with new problems unrelated to their initial presentation. Physician-related factors were the primary reason for return in 92 cases (18%). Problems with our public health-care system prompted return in 18 cases (4%). Eighty-seven returning patients (19%) required emergency hospitalization, including 28 discharged due to physician errors. Regular case review of short-term returns to the ED should be included in a comprehensive ED-based program of quality assurance.

Emergency Service, Hospital↗
PubMed1988

Indigenous human cutaneous leishmaniasis caused by Leishmania tropica in Kenya.

Six Leishmania isolates from 3 indigenous Kenyans (2 isolates from one patient) and 2 Canadian visitors in Kenya were characterized by cellulose acetate electrophoresis. The isolates were compared among themselves and with reference strains of Leishmania donovani, L. aethiopica, L. major, L. tropica, and L. arabica using 9 enzymes: malate dehydrogenase (MDH), malic enzyme (ME), phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), aspartate aminotransferase (ASAT), adenylate kinase (AK), mannose phosphate isomerase (MPI), glucose phosphate isomerase (GPI), and phosphoglucomutase (PGM). Enzyme migration patterns of isolates from the 3 indigenous Kenyans were indistinguishable from those of 2 L. tropica reference strains. The isolates from the 2 Canadians yielded migration patterns of 7 enzymes that were indistinguishable from those of 2 L. tropica reference strains. However, migration patterns of 2 enzymes, PGM and ME, differed from all migration patterns of the 10 reference strains. Balb/c mice were inoculated with stationary phase promastigotes cultured from 3 stabilates from the lesions of 2 of the Kenyan patients. The mice developed no gross pathological lesions in 6 months time. All of the study patients developed cutaneous leishmaniasis while living in or visiting districts in Central and Rift Valley Provinces, Kenya. This is the first report of human cutaneous leishmaniasis caused by L. tropica indigenous to Africa south of the Sahara.

Adolescent↗
PubMed1985

Regional variation in prevalence of antibody against human T-lymphotropic virus types I and III in Kenya, East Africa.

The prevalence of antibodies against HTLV-III and -I was studied among populations of 6 distinctly different regions of Kenya, an equatorial African country in which AIDS has rarely been observed. Overall, 21% of subjects had ELISA reactions suggesting the presence of antibody against HTLV-III. The frequency of HTLV-III antibodies was highest among the Turkana people (50%) and lowest among the Masai (8%). Prevalence increased with age but was not related to sex. The pattern of ELISA-detected antibody against HTLV-I was similar. The specificity of these antibodies was supported by Western blot analysis of a subset of sera with high and low ELISA ratios, in which 66% and 73% of those with ELISA ratios considered positive (= greater than 5.0 in this study) also had a profile of bands consistent with HTLV-III and HTLV-I respectively. The antibodies detected were not cross-reactive between HTLV-III and HTLV-I on Western blot analysis. In a series of subjects with various parasitic and infectious diseases, patients with idiopathic splenomegaly and with schistosomiasis had a high proportion of antibodies against both HTLV-III and HTLV-I. This survey shows that reactivity in the ELISA HTLV-III and HTLV-I assays are common among Kenyans but vary considerably by region.

Adolescent↗
PubMed1985

Arthrographically assisted splint therapy.

Occlusal splints are often constructed to aid in treatment of temporomandibular joint meniscus displacement. Techniques for arthrographically locating the point of meniscal displacement and for fabrication of an appropriate occlusal splint are described.

Cartilage, Articular↗
PubMed1985

Evaluation of arthrographically assisted splint therapy in treatment of TMJ disk displacement.

Eighty-two patients with audible clicking were evaluated and treated with splints made by using arthrographic assistance. In the course of this study, it became apparent that the later the opening click, the earlier the closing click. It was not always possible to auscultate or palpate either an opening or a closing click in many patients with arthrographic findings of disk displacement with reduction. Since the opening click was the only audible sound in some patients, clinical judgment alone cannot be used to replace the displaced disk at an optimal mandibular position. The elimination of the opening click does not always signify recapture of the disk. Maxillomandibular and incisal relationships limit the amount of protrusion possible to recapture the displaced disk.

Adolescent↗
PubMed1984

Cutaneous leishmaniasis in Kenya: transmission of Leishmania major to man by the bite of a naturally infected Phlebotomus duboscqi.

One leishmanial stock was isolated from a Phlebotomus duboscqi female captured in Baringo District, Kenya, and others from papular lesions that developed at sites where this sandfly had fed on a man. When characterized by cellulose acetate electrophoresis (eight enzymes examined), these isolates proved to be identical to known Leishmania major strains from man and a rodent (Arvicanthis sp.) and different from L. donovani and L. adleri, which also occur in Baringo. This is the first case of human cutaneous leishmaniasis caused by L. major reported from Kenya.

Electrophoresis, Cellulose Acetate↗
PubMed1979

Sensory deprivation and homeostasis.

Most afferent inputs are sensory stimulants, and physical activity is probably one of the most significant of all sensory stimulations. Gravity is a constant stimulus. These demands are also known as stress, and the stressor effect as the general adaptation syndrome (Selye). In this study, these demands are called sensory afferent stimuli, which are necessary triggers to start the hypothalamus-pituitary-adrenal mechanism and thus maintain the general mechanical, autonomic and metabolic functions of the body in the state of homeostasis. If the sensory stimulus is removed, there is no stressor effect and the cycle of response is eliminated. This results in a decreased hypothalamus-pituitary response and a decreased production of ACTH and corticoids. A decrease in the sensory input creates changes in the central nervous system and in the musculoskeletal system which are compatible with lack of the hypothalamus-pituitary responses. When a person becomes ill, physical inactivity as well as sensory and perceptual deprivation are at a maximum, and the absence of these stimuli interrupts the cycle of homeostasis. Physical activity is one of the most important stressors (sensory input) or triggering mechanisms for the cycle of homeostasis (hypothalamus-pituitary-adrenal cycle). Therefore, it is imperative to provide the patient with physical activities which ensure motion and take into account the effect of gravity. This is best accomplished by a program of physical, occupational and recreational therapy.

Aged↗
PubMed1977

Signs of sensory deprivation versus cerebral injury in post-hip-fracture patients.

Patients with a primary diagnosis of "postoperative hip fracture" often have a poor prognosis because of their inability to participate in rehabilitation programs. They tend to remain in a state of physical inactivity and sensory deprivation. The signs and symptoms of head injury associated with the hip fracture may be overlooked and attributed to sensory deprivation. Thirty-nine patients with fractured hip and 18 with multiple fractures were studied by means of electroencephalography, echoencephalography, and computer axial tomography. In 7, the findings indicated a cerebral lesion. At operation, a subdural hematoma was found in 5 patients and a tumor in 2; all but one made a dramatic recovery. Thus, after hip fracture, it is important that the patient be tested appropriately so that signs and symptoms of sensory deprivation may not be confused with those of an occult head injury. When indicated, surgical intervention may be a life-saving process.

Age Factors↗
PubMed1976

Sensory deprivation in geriatric patients.

Sensory deprivation speeds up the degenerative changes normally associated with aging and enhances the loss of functional cells in the central nervous system. Since it connotes reduction or absence of stimulation of the five senses, it involves the patient's physical activity, social relationships, intellectual status and overall "value system." Geriatric patients with various illnesses are particularly vulnerable to sensory deprivation, which becomes increasingly pronounced as physical or mental deterioration progresses. All cells require stimulation for continued growth and activity; lack of stimulation leads to atrophy, with secondary physical or psychosocial abnormalities. Depression acts as a negative reinforcement of stimuli, and anxiety acts as a blocking mechanism. The goal of rehabilitation is to maintain and strengthen the patient's social values and to preserve mental and physical motility. The recommended procedure involves assessment of medical, psychologic and social factors, and determination of whether organic disease is present. A specific treatment plan to meet the individualized needs of each patient is then established so as to minimize sensory deprivation and maximize physical and mental functioning. Re-evaluation (physical and psychologic) at regular intervals establishes a pattern not only for individual comparison but for comparison with results in untreated control groups.

Aged↗
PubMed1975

Evaluation of a multidisciplinary care program for stroke patients in a day care center.

With funds received by the Rehabilitation Center at Martin Place Hospital East from the Michigan Association of Regional Medical Programs, a Rehabilitation Day Care Center was established. Initially it was called the Stroke Day Care Center (SDCC). Its purpose was to provide comprehensive care to patients with disabilities due to stroke and related diseases according to the "day at the hospital, night at home" concept. A complex of medical and allied services was furnished, based upon the patient's attendance at the SDCC from one to five days a week. The goal was to promote for the patient an earlier return of functional vocational, social and home activities by effectively providing him and his family with multidisciplinary care. In this SDCC program the main emphasis was on testing the feasibility of lowering the cost of stroke-patient care by: a) shortening the hospital stay; b) reducing the need for in-patient care in facilities for non-acute illness; c) shortening the stay in extended care facilities; d) returning younger stroke victims earlier to the labor force; e) identifying the number of stroke patients who could live at home if provided with a modified day care program; and f) assessing the need for purely recreational and social activities in future programs. The evaluation was based on a comprehensive study of 108 patients during the period February 1972 to June 1973. This project is offered as a model for the development and expansion of rehabilitation-recreation day care centers for the handicapped of all ages.

Activities of Daily Living↗