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Biomedical subjects

R L Carter

Publications and source records attributed to R L Carter.

At least 127 records · Page 7Linked to original sources

An epidemiological study of natural in utero infection with bovine leukemia virus.

The purpose of this study was to examine rates of natural in utero infection with bovine leukemia virus for association with breed, sex, dam age, dam parity and time of maternal seroconversion. Analyses conducted for breed and sex, dam age and parity and time of maternal seroconversion were the FUNCAT procedure for categorical data, Wilcoxon Rank Sums test and Fisher's exact test, respectively. A total of 223 calves born between July 1979, and September 1980, to cows infected with bovine leukemia virus in the University of Florida Dairy Research Unit herd were tested for detectable bovine leukemia virus antibodies prior to the consumption of colostrum. Sera were tested for antibodies by agar-gel immunodiffusion and radioimmunoprecipitation using the glycoprotein-51 antigen. In a group of 125 calves in which in utero infection could be confirmed through serological follow-up (group A), eight calves (6.4%) had precolostral bovine leukemia virus antibodies. For all 223 calves (group B), 18 (8.1%) had detectable bovine leukemia virus antibodies. For calves in group A, no associations were detected between precolostral bovine leukemia virus antibodies and breed (p = 0.66), dam age (p = 0.86), dam parity (p = 0.83), or time of maternal seroconversion to bovine leukemia virus (p = 0.50). However, precolostral bovine leukemia virus antibodies were found in 17.4% of the males and 3.6% of the females in group A (p = 0.11) and in 12.4% of the males and 3.6% of the females in group B (p = 0.04).

Age Factors↗

Assessment of the diet of patients with rheumatoid arthritis and osteoarthritis.

There have been many and divergent thoughts expressed both in the scientific and in the lay literature regarding diets for patients with arthritis (1-8). However, few experimental observations pertain to either the nutritional status of arthritis patients or the clinical value of putative nutritional therapies (1-8). Until such time as the notion that dietary manipulation can alleviate particular symptoms for selected patients is proved, it is prudent to advise patients to maintain sound nutritional practices in accordance with contemporary standards (4-8, 13-16). Our data indicate that many arthritis patients are at least marginally inadequate in selected nutrients, some of which (vitamin E and zinc) might relate to immunologic events important in perpetuating the disease. These observations provide a basis for nutritional counseling of arthritis patients.

Adolescent↗

Aphasia and speech organization in children.

A long-standing controversy concerns whether lateralized cerebral specialization for speech and language is present at the time of language origins (developmental invariance) or whether it gradually develops from initial bilaterality (developmental progression). Thus controversy is complicated by conflicting reports of the incidence of childhood aphasia. The discrepancies are largely due to one early study. When methods for estimating speech organization distributions are applied to later studies, the developmental invariance position is supported.

Adolescent↗

Fetal death in utero: effect on estrone, estradiol-17 beta and progesterone levels in the ewe.

Polyvinyl catheters were placed in the maternal femoral artery (MA) and maternal uterine vein (UV) of 11 near-term ewes and in the umbilical vein of their fetuses. 1-5 days postoperatively 100 ml of air were injected into the umbilical vein of 7 fetuses. 4 fetuses served as controls. Samples of blood from MA were taken 15 min prior to air embolism and every 15 min for 3 h, then at +4, +5 and +6 h after air injection. Plasma levels of estrone (E1) estradiol (E2) and progesterone (P) were determined by radioimmunoassay. In MA and UV of treated ewes there was a significant decrease in P, but not in E1 or E2 after fetal death compared to control ewes. Control levels of P in MA were 9.6 ng/ml; values at 1, +2, +4 and +6 h were 8.8, 3.3, 2.3 and 1.2 ng/ml, respectively.

Animals↗

A statistical approach to the determination of the fertile period.

17 beta-Estradiol (E2), basal body temperature (BBT) and luteinizing hormone (LH), were measured in normally menstruating women. The preovulatory E2 observations were characterized by variations about a constant level during the preovula-peak. The BBT observations typically varied about a constant level during the preovulatory phase then about a higher constant level during the postovulatory phase. The change points in E2 and BBT were detected using a Bayesian detection rule and a midcycle 'fertile period' was marked off. The midcycle 'fertile periods' appear to bracket the ovulation event and the method shows promise as a natural family planning method. Several practical limitations of the method are discussed.

Bayes Theorem↗

Pain and dysphagia in patients with squamous carcinomas of the head and neck: the role of perineural spread.

Clinical and pathological features of perineural spread have been investigated in patients with squamous carcinomas at several sites in the head and neck. In 100 surgical cases, the clinical and pathological findings were congruent in 76%. Combined clinical and histological evidence of perineural invasion was recorded in 33% and the overall incidence of nerve involvement detected morphologically was 44%. Perineural infiltration was demonstrated histologically in 51% of major excisions from the buccal cavity and in 34% of resections from the oropharynx, hypopharynx and cervical oesophagus. The neurological findings were dominated by hypoaesthesia, dysaesthesia and referred pain - mainly in the territories of cranial nerves V and IX. Multiple and/or sequential nerve involvement was occasionally seen. No correlation was established between nerve invasion and metastasis to regional lymph nodes. Long-distance infiltration of nerve trunks, and multiple involvement, are grave prognostic features.In 17 terminal patients submitted to autopsy, 65% had combined clinical and pathological evidence of perineural spread and the overall incidence of nerve involvement detected morphologically was 88%. Sensory changes again predominated. Multiple nerve involvement was observed in 35%. An apparently new `dysphagia syndrome' is described in 4 patients with oropharyngeal carcinomas in whom gross mechanical obstruction was simulated by a combination of perineural spread of tumour into the ipsilateral vagal trunk, sometimes accompanied by segmental infarction, variable invasion of the sympathetic chain, and `splinting' of the pharynx by local fibrosis and tumour in the soft tissues of the neck. Short-term palliation was achieved in these patients with high-dose steroids.

Adult↗

Calcium phosphate deposition disease in great danes.

A new clinicopathologic syndrome, possibly familial, in Great Dane dogs, resembles the familial childhood variant of calcium pyrophosphate dihydrate deposit disease in man, except that the mineral deposits were composed of amorphous calcium phosphate or hydroxyapatite rather than pyrophosphate. The syndrome was characterized clinically by paraplegia and incoordination in very young puppies which was caused by concentric constriction of the posterior cervical spinal cord. Canal stenosis resulted from dorsal displacement of the seventh cervical vertebra and deformation of the vertebral articular processes. Mineral deposition in the diarthrodial joints of the axial skeleton could be seen on radiographs of weanling puppies, and the appendicular skeleton became involved as the dogs matured. Periarticular mineralization of the limbs was associated with shorter bones, a thin cortex, abnormal bone curvature, and increased medullary trabeculae. Bone alterations were associated with abnormalities of the growth plate, which had focal areas of cartilage calcification. Soft tissue mineralization, seen in all dogs, was a primary feature of the disease process. Serum calcium concentrations were within the normal range, but serum phosphorus concentrations were decreased.

Animals↗

Decay of colostral antibodies to bovine leukemia virus with application to detection of calfhood infection.

An estimated weighted-regression method was used to describe the decay of colostral bovine leukemia virus (BLV) antibodies in the calf, as measured by agar-gel immunodiffusion with glycoprotein antigen. The prediction equation, based on 473 observations from 130 animals, was log10 inverse titer = 1.29 -0.012 age (days). The half-life of BLV antibodies was estimated to be 25.8 days. Ages at which colostral antibodies were last detected were between 51 and 187 days. Normal limits of antibody decay were estimated and used to identify virus-induced active antibodies in calves during the colostral antibody period. Calves known to be infected were identified between 2 and 180 days of age, using 95% limits. Application of this procedure for the early serologic detection of BLV-infected calves in eradication or control programs is discussed.

Age Factors↗

The diagnosis and surgical management of olfactory neuroblastoma: the role of craniofacial resection.

The diagnosis and clinical management of olfactory neuroblastoma are discussed. Computerized tomography is a valuable means of assessing the pre-operative extent of disease and the efficacy of subsequent major surgery. The tissue diagnosis is facilitated by electron microscopy, demonstrating the presence of dense core vesicles and cytoplasmic filaments. Radiotherapy followed by craniofacial resection is the treatment of choice for olfactory neuroblastomas that are locally extensive at presentation.

Adolescent↗

Ten human carcinoma cell lines derived from squamous carcinomas of the head and neck.

Ten cell lines of human squamous carcinomas of the tongue and larynx have been established from surgical specimens removed from 36 unselected patients, in order to provide systems for investigating the invasive and tissue-destructive capacity of squamous carcinomas of the head and neck. The morphology, ultrastructure and growth characteristics of the 10 lines are described. Detailed cytogenetic analysis of the first 4 lines indicates that each is karyotypically unique, with no evidence of cross-contamination. Nine of the 10 cell lines secrete immunoreactive beta human chorionic gonadotrophin (beta-hCG) in the culture medium. No correlation was demonstrated between the ability of the cell lines to secrete plasminogen activator and their capacity to grow in soft agar or as xenografts in immune-deficient mice.

Aged↗

Five human tumour cell lines derived from a primary squamous carcinoma of the tongue, two subsequent local recurrences and two nodal metastases.

Five tumour cell lines have been derived from a primary squamous carcinoma of the tongue, from 2 subsequent local recurrences, and from 2 lymph-node metastases--all from the same patient. While the cell lines shared many morphological and biochemical characteristics, those derived from recurrences and metastases appeared to be less differentiated, were less well organized in culture, and displayed fewer desmosomes and tonofilaments than cells in the primary tumour line. A recurrent line showing greatest morphological divergence from the primary tumour line also demonstrated the greatest differences at the ultrastructural level, in increased production of plasminogen activator and in the composition of cell-surface glycoproteins.

Carcinoma, Squamous Cell↗

Some mechanisms of local bone destruction by squamous carcinomas of the head and neck.

An in vitro osteolysis assay with 45Ca-labelled mouse calvaria has been used to investigate mechanisms of direct bone invasion by squamous carcinomas of the head and neck. Short-term (3-day) organ cultures of 8 fresh squamous carcinomas showed varying degrees of in vitro bone-resorbing activity which was blocked by indomethacin, an inhibitor of prostaglandin synthesis. Supernatant media from 6 established cell lines also induced bone resorption in vitro and evoked an osteoclastic response in the cultured calvaria. Osteolysis by supernatant media was not blocked by indomethacin in all the tumour-cell lines, and the production of non-prostaglandin osteolysins by the indomethacin-resistant lines is postulated. The two principal findings that emerge are: (1) Stimulants for osteoclastic activity are derived from both squamous-carcinoma cells and from host cells in the tumour stroma. (2) These stimulants are diverse. Indomethacin-sensitive agents, presumed to be prostaglandins, are most convincingly demonstrated in the fresh tumours. Indomethacin-resistant agents, presumably not prostaglandins, are more characteristic of the carcinoma cell lines.

Adult↗

An unexpected fungal infection in a patient with leukaemia.

A 58-year-old man, who was entering remission from acute monocytic leukaemia, died unexpectedly after five days of fever. Cultures of necropsy material grew the yeast Trichosporon beigelii, and subsequent histological examination showed a widely disseminated infection. This fungus usually causes a localised lesion of the hair shaft (piedra). Deep-seated infections due to Trichosporon spp. have been recorded infrequently and disseminated infections on only five previous occasions. None of these has been from the United Kingdom. This case report describes some of the difficulties of diagnosis.

Humans↗

Reliability and validity of the 24-hour recall.

The reliability and validity of the 24-hour dietary recall method was tested statistically by comparing observed with recalled intakes of kilocalories and protein. Data on observed intake of 28 children, aged 10 through 12, with asthma, cystic fibrosis, or diabetes, participating in a summer camp program, were obtained by unobtrusive observation. The same subjects were interviewed within 24 hours after the observation. Intakes of kilocalories and of protein were computed for both observed and recalled data. The two sets of data were compared by paired t-test and regression analysis. A large and significant difference was found between mean recalled and mean observed intakes for both kilocalories and protein. This coupled with a low but significant coefficient for reliability limits the usefulness of this dietary assessment tool in the age group studied.

Child↗

A Bayesian change-point problem with an application to the prediction and detection of ovulation in women.

Under the assumptions of independent normally distributed and sequentially observed responses, a Bayesian rule for detecting a change from a constant mean response is derived. It is known that both basal body temperature (BBT) and preovulatory estrogen values undergo such a change in mean value at some random time during the menstrual cycle. The Bayesian rule is applied to estrogen to predict ovulation and to BBT to detect ovulation. Data from an aggregate of women are used to obtain prior information about the change-points and the parameters that define the changes in estrogen and BBT. A method is proposed by which the accumulation of information for a specific women can be incorporated into the aggregate prior information.

Bayes Theorem↗