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Biomedical subjects

C L Miller

Publications and source records attributed to C L Miller.

At least 73 records · Page 4Linked to original sources
PubMed1991

Shunt lengthening: a descriptive review.

Shunt lengthening is a neurosurgical procedure unique to the pediatric patient. It is considered to be a minor operation to the professional, but means another hospitalization to parents of children who have often times already had many hospitalizations. A review of 27 children who underwent routine shunt lengthening revealed that none developed the most common complication of infection following this operation. After questioning parents about their need for information on shunt lengthening, a fact sheet explaining the procedure was written. As a result of our findings and need to be more cost efficient while safely caring for patients, we have been successful in changing nursing management of these children.

Body Height↗
PubMed1991

Regulation and a possible stage-specific function of Oct-2 during pre-B-cell differentiation.

The Oct-2 gene appears to encode a developmental regulator of immunoglobulin gene transcription. We demonstrate that the Oct-2 gene is expressed at low levels in a variety of transformed pre-B-cell lines and is induced specifically in these cells by lipopolysaccharide signalling. This work extends an earlier observation in the pre-B-cell line 70Z/3 and therefore suggests that the inducible expression of the Oct-2 gene, like that of the kappa gene, is a characteristic feature of the pre-B stage of B-cell development. In 70Z/3 cells, the lymphokine interleukin-1 also induces the expression of the Oct-2 and kappa loci. Interestingly, expression of the Oct-2 gene is rapidly induced at the transcriptional level and may not require de novo protein synthesis. Since the changes in the activity of the Oct-2 locus completely correlate with the changes of the activity of the kappa locus, the two genes may be transcriptionally regulated by a common trans-acting factor. In 70Z/3 cells, transforming growth factor beta, an inhibitor of kappa-gene induction, blocks the upregulation of Oct-2 but not the activation of NF-kappa B. These results suggest that the combinatorial action of increased levels of Oct-2 and activated NF-kappa B may be necessary for the proper stage-specific expression of the kappa locus.

Animals↗
PubMed1990

IL-4 potentiates the IL-2-dependent proliferation of mouse cytotoxic T cells.

In addition to the regulation of B lymphocyte growth and differentiation, the cytokine IL-4 (BSF-1) exerts effects on T lymphocytes and other bone marrow-derived lineages. We show here that recombinant mouse IL-4 synergizes with low levels of IL-2 to increase the yield of cytotoxic activity in a primary MLR, and the proliferation of both cloned IL-2-dependent CTL lines and cells obtained from a primary MLR. IL-4 did not induce the proliferation of any of several cloned CTL cell lines on its own. It also did not replace IL-2 in stimulating the growth or reactivation of quiescent, antigen-dependent CTL clones. However, IL-4 was synergistic with IL-2 after reactivation of the quiescent cells with antigen plus IL-2. Enhancement by IL-4 of the IL-2-driven proliferation of an antigen-independent line was blocked by the addition of anti-IL-4 monoclonal antibody. Although incubation of the CTL clones with IL-4 or with IL-2 plus IL-4 induced a transient increase in the expression of the mRNA encoding the 55 kDa IL-2 receptor, no change in the number or affinity of IL-2 receptors because of IL-4 was detected. This suggests that IL-4 does not potentiate the IL-2 response by altering IL-2 receptor levels. Instead, we propose that the synergistic effect of IL-4 is mediated by a different signalling mechanism from that used by IL-2.

Animals↗
PubMed1990

Development of precytotoxic T cells in cyclosporine-suppressed mixed lymphocyte reactions.

Cyclosporine (CsA) blocked the generation of cytolytic activity in a primary MLR of mouse spleen cells. As expected from the known mechanism of action of this drug, it also blocked the accumulation of IL-2 during the MLR. Addition of human rIL-2 did not overcome the inhibition of CTL generation, even when it was added daily to keep its level similar to that produced in a normal MLR. Daily addition was necessary, because the CsA-inhibited MLR consumed IL-2, either by utilization or degradation. The outcome of a 5-day MLR in the presence of CsA (CsA-MLR) depended on whether or not IL-2 was continuously present. In the presence of IL-2, there was no generation of CTL activity, probably because such cultures contained IL-2-dependent suppressive elements described previously. However, when day 5 CsA-MLR cells generated in the absence of IL-2 were washed and recultured with human rIL-2, there was a burst of CTL activity, with a more than 50-fold increase in alloantigen-specific cytotoxicity within 24 to 48 h. This increase is not explainable simply by the proliferation of existing effector CTL. The noncytotoxic cells produced in an MLR in the presence of CsA, and which can be rapidly activated to cytotoxic effector cells by IL-2, are termed "precursor-effector CTL" (peCTL). They could be detected by day 3 of a primary CsA-MLR culture. Their conversion to effector CTL by IL-2 was not inhibited by CsA. Exposure of peCTL to IL-4 also generated CTL activity, to a somewhat lesser degree than IL-2, but the IL-4-induced activation was inhibited by CsA, suggesting that it depended on the induction of another CsA-sensitive lymphokine. The intracellular levels of mRNA encoding the CTL-specific serine esterases CCP1 and CCP2 (granzymes B and C, respectively) increased rapidly during the IL-2-driven conversion of peCTL to effector CTL. This study demonstrates that in the presence of CsA precursors for CTL can accumulate, and that these can be rapidly converted to cytotoxic effector cells by IL-2.

Animals↗
PubMed1990

Delayed growth in two German shepherd dog littermates with normal serum concentrations of growth hormone, thyroxine, and cortisol.

Four German Shepherd Dogs from a litter of 10 were evaluated because of postnatal onset of proportionate growth stunting that clinically resembled well-documented hypopituitary dwarfism in that breed. Although 2 pups had histologic evidence of hypopituitarism, the remaining 2 pups had normal serum growth hormone concentration and adrenocorticotropin secretory capability, and normal adrenal function test and thyroid function study results. Furthermore, the initially stunted German Shepherd Dogs grew at a steady rate until at 1 year, body weight and shoulder height approximated normal measurements. Seemingly, delayed growth in these pups may represent one end of a clinical spectrum associated with hypopituitarism in German Shepherd Dogs.

Adrenal Cortex↗
PubMed1990

Antigen presentation by the CD4 positive monocyte subset.

Although CD4 antigen is expressed on monocytes (MO), its functional role is uncharacterized. In this study, isolated human MO were separated into CD4+ and CD4- MO subsets and assessed for presentation of tetanus toxoid. The CD4- MO subset had decreased antigen presenting cell (APC) capacity as well as increased PGE2 production when compared to the CD4+ MO subset. Addition of a cyclo-oxygenase inhibitor (Indomethacin) did not restore the CD4- MO subset's APC capacity to that of the similarly treated CD4+ MO subset, eliminating differential PGE2 production as the primary cause of differential APC capacity. Production of monokines such as IL-1 and plasminogen activator, which affect APC capacity, was similar in the CD4 MO subsets. However, tumor necrosis factor (TNF) production (IFN gamma plus MDP-induced) of the CD4+ MO subset was slightly greater than that of the CD4- MO. CD4- MO's lower APC capacity is not totally explained by their differential IL-1, TNF, or PGE2 production.

Adult↗
PubMed1990

Anterior protrusion of retroperitoneal processes. A mimic of lesser sac or gastrohepatic masses.

The space between the left lobe of the liver and the lesser curvature of the stomach normally contains intraperitoneal structures. These include the gastrohepatic recess of the greater peritoneal cavity, the medial recess of the lesser sac and the interposed gastrohepatic ligament. An anterior protrusion of retroperitoneum can project into this space, dorsal to the posterior reflection of the medial compartment of the lesser sac. Tumors that extend into this fossa are anterior and medial to the fundic and upper body region of the stomach. These tumors may cause confusion regarding their origin if the radiologist is not aware of the existence of this retroperitoneal protrusion. Between 1982, and 1986, 183 patients with pancreatic cancer were hospitalized at our institution, 63 of whom had computed tomography (CT) scans of the abdomen. Four of these patients (6.3%) demonstrated direct tumor extension anterior to the stomach. During this same period, four large benign retroperitoneal tumors also exhibited this finding. Masses in the gastrohepatic interval between the liver and stomach can be extensions of retroperitoneal processes and should not be assumed to represent intraperitoneal involvement.

Diagnosis, Differential↗
PubMed1989

Limited sensitivity of ultrasound for the detection of rotator cuff tears.

Bilateral rotator cuff sonography was performed on 56 patients referred for shoulder arthrography to detect rotator cuff tears. Since one patient had bilateral arthrography there were 57 arthrograms. Twenty-seven shoulders had rotator cuff tears shown on arthrography, 15 of which were detected by sonography. Eleven were false negative by sonography, and one was indeterminate. Of the 30 shoulders with negative arthrograms, 28 had normal sonograms and two were false positive. Sensitivity was 58%, specificity was 93% and overall accuracy was 77%. The positive and negative predictive values were 88% and 72%. These results suggest that sonography has limited value in screening patients for rotator cuff tears and that a positive sonographic reading is more reliable than a negative one. Theories relating to the variable anatomic configuration of a tear are postulated to explain these results, which differ from those previously reported.

Adult↗
PubMed1989

Barriers to implementation of a prenatal care program for low income women.

By the middle of the second year of the Michigan Prenatal/Postpartum Care (PPC) program to provide pregnancy-related services to low income women who were ineligible for Medicaid or other insurance, only 25 per cent of the participating health departments were enrolling greater than 90 per cent of contracted potential clients. Using a survey of program directors and relevant state documents, we identified several barriers to successful implementation: institutional (program complexity, high levels of administrative concerns along with low levels of communication between local health departments and providers); economic (inadequate resources for provider reimbursement, outreach, transportation, high-risk pregnancies, or administrative overhead); psychological (servicing populations with multiple and hard to care for problems, potential discomfort of low income women with traditional providers); and informational (insufficient information about the program infiltrating the target community).

Female↗
PubMed1989

Rotator cuff tears: prospective comparison of MR imaging with arthrography, sonography, and surgery.

Thirty-eight patients with suspected rotator cuff tears were examined at 1.5 T by using a loop-gap resonator surface coil. The MR findings were compared prospectively in a blinded fashion with the results from double-contrast arthrography in all 38 patients, high-resolution sonography in 23 patients, and surgery in 16 patients. In the total group of 38 patients, MR imaging detected 22 of 22 tears and 14 of 16 intact cuffs as determined by arthrography. In the 16 surgically proved cases, MR and arthrography showed identical results, with 92% sensitivity in the diagnosis of 12 tears and 100% specificity in the diagnosis of four intact cuffs. In a subgroup of 23 patients, sonography detected nine of 15 tears and seven of eight intact cuffs as determined by comparison with arthrography. In 10 surgically proved cases, sonography was 63% sensitive in the diagnosis of eight rotator cuff tears and 50% specific in the diagnosis of two intact cuffs. For the diagnosis of rotator cuff tears, MR imaging is comparable to arthrography in both sensitivity and specificity. In this study, sonography was not as accurate in the diagnosis of rotator cuff tears as were the other two techniques. These results suggest that MR imaging should be considered the noninvasive test of choice for patients with suspected rotator cuff disease.

Arthrography↗
PubMed1988

Surveillance of antibody to measles, mumps, and rubella by age.

Before the introduction of measles, mumps, and rubella vaccine a survey was carried out to measure antibody prevalence to the three viruses by age. A total of 8716 samples of serum collected by five public health laboratories in different parts of England during 1986-7 were tested. Despite the current measles vaccination programme 60% of children aged 1-2 years did not have measles antibody and over 80% did not have antibodies to mumps and rubella. In the 3-4 year age group 17% of the children were susceptible to measles, 55% to mumps, and 73% to rubella. The results suggest that vaccinating children early in the second year of life will be necessary to eliminate the three diseases. The survey provides baseline data for continuing surveillance of the immediate and long term effects of the new vaccination strategy.

Adolescent↗
PubMed1987

The influence of subjective factors on temporary threshold shifts after exposure to music and noise of equal energy.

The present study examined the influence of subjective factors on temporary threshold shifts (TTS) after exposure to noise and music. Two groups of subjects, those who indicated liking and those who indicated disliking pop/rock music, were exposed to both noise and music on separate occasions. Subjects who liked the music exhibited less TTS following music than noise. They also exhibited less TTS in music than the subjects who disliked the music. Those who disliked the music evidenced greater magnitude of TTS in music than noise.

Attitude↗