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L M White

Publications and source records attributed to L M White.

At least 55 records · Page 3Linked to original sources
PubMed1996

Enlargement of the third intercondylar tubercle of Parsons as a sign of osteoarthritis of the knee: a paleopathologic and radiographic study.

PURPOSE: To correlate presence and size of the third intercondylar tubercle of Parsons (TITP) with occurrence and severity of osteoarthritis of the knee. MATERIALS AND METHODS: In 100 paleopathologic tibial specimens and on 160 clinical knee radiographs, size of the TITP was correlated with osteoarthritis of medical and lateral femorotibial joints (FTJ) and with prominence of tibial spines. RESULTS: TITP size correlated significantly with osteoarthritis of the tibial plateau in the paleopathologic specimens (P<.0001). TITP size correlated significantly with osteoarthritis of medial FTJ and tibial spines on radiographs (P<.0001). Of 85 patients without osteoarthritis of the medial FTJ, 49 (58%) had no TITP, 33 (39%) had small TITPs, and three (4%) had medium or large TITPs. TITPs were found in 15 (88%) of 17 patients with pronounced osteoarthritis. CONCLUSION: Frequency and prominence of TITPs are increased in patients with osteoarthritis of the medial FTJ and prominent tibial spines. Prominent TITP is a secondary sign of osteoarthritis. At histologic examination, increasing size of TITPs represents osteophytosis or enthesopathy of the TITP.

Adolescent↗
PubMed1996

Does altered biomechanics cause marrow edema?

PURPOSE: To determine if altered weight bearing causes the appearance of marrow edema on magnetic resonance (MR) images. MATERIALS AND METHODS: Twelve volunteers underwent MR imaging with a short inversion time inversion-recovery (STIR) sequence at 1.5 T. The hips, knees, ankles, and feet were evaluated before and 2 weeks after altered weight bearing achieved with overpronation of one foot. Three volunteers underwent imaging a third time, 2 weeks after overpronation was stopped. Two observers assessed the images for evidence of marrow edema. RESULTS: Changes were seen on images in 11 volunteers; the overpronated side only was affected in 10. Most changes occurred in the foot followed by the tibia and the femur. Most changes were a diffuse increase in marrow edema. In two volunteers, the changes resembled those of stress fractures. CONCLUSION: Altered weight bearing should be added to the list of causes of increased medullary signal intensity (ie, marrow edema) on MR images.

Adult↗
PubMed1996

Shoulder impingement syndrome: influence of shoulder position on rotator cuff impingement--an anatomic study.

OBJECTIVE: The purpose of the study was to investigate the relationship of the distal supraspinatus tendon to the coracoacromial arch on radiographs and MR imaging at various shoulder positions. MATERIALS AND METHODS: Radiopaque and gadolinium-impregnated markers were sutured to the distal aspect of the supraspinatus tendon and along the coracoacromial ligament in three cadavers. While varying positions of the shoulder, we obtained gross anatomic visualization, radiographs, and MR images. RESULTS: Impingement of the distal aspect of the supraspinatus tendon between the acromion and the greater tuberosity of the humerus was well visualized during forward flexion and abduction of more than 30 degrees. Shoulder impingement was best seen at 60 degrees forward flexion, 60 degrees abduction, and internal rotation. CONCLUSION: MR imaging of different shoulder positions may help reveal the pathogenesis of shoulder impingement syndrome.

Aged↗
PubMed1996

Allele-specific replication of 15q11-q13 loci: a diagnostic test for detection of uniparental disomy.

Allele-specific replication differences have been observed in imprinted chromosomal regions. We have exploited this characteristic of an imprinted region by using FISH at D15S9 and SNRPN (small nuclear ribonucleo protein N) on interphase nuclei to distinguish between Angelman and Prader-Willi syndrome patient samples with uniparental disomy of chromosome 15q11-q13 (n = 11) from those with biparental inheritance (n = 13). The familial recurrence risks are low when the child has de novo uniparental disomy and may be as high as 50% when the child has biparental inheritance. The frequency of interphase cells with asynchronous replication was significantly lower in patients with uniparental disomy than in patients with biparental inheritance. Within the sample population of patients with biparental inheritance, those with altered methylation and presumably imprinting center mutations could not be distinguished from those with no currently detectable mutation. This test is cost effective because it is performed on interphase cells from the same hybridized cytological preparation in which a deletion is excluded, and additional specimens are not required to determine the parental origin of chromosome 15.

Adult↗
PubMed1995

Study of osteomyelitis: utility of combined histologic and microbiologic evaluation of percutaneous biopsy samples.

PURPOSE: To determine the utility of combined histologic and microbiologic evaluation of percutaneous biopsy samples in cases of suspected osteomyelitis. MATERIALS AND METHODS: Twenty-five patients with suspected osteomyelitis were prospectively studied over a 1-year period. With usual trephine techniques under radiologic guidance, core and aspiration biopsy samples were obtained in each patient for both histologic and microbiologic analyses. RESULTS: Sixteen biopsy specimens demonstrated histologic evidence of osteomyelitis. Of these, eight were also culture positive. Seven of the eight culture-negative, histologically positive cases were interpreted as chronic osteomyelitis. In no patient were cultures positive and histologic findings negative. Three of 19 patients with proved osteomyelitis had negative histologic and microbiologic findings. The sensitivity of culture in the diagnosis of osteomyelitis in our study was 42%; the sensitivity of both culture and histologic findings was 84%. CONCLUSION: Although the volume of a biopsy specimen is a major determinant of culture yield, a portion of a percutaneous biopsy sample should be histologically evaluated for possible osteomyelitis.

Acute Disease↗
PubMed1995

Exacerbation of congestive heart failure after administration of polyethylene glycol-electrolyte lavage solution.

OBJECTIVE: To report a patient with exacerbation of congestive heart failure after administration of polyethylene glycol-electrolyte lavage solution (PEG-ELS). METHODS: A MEDLINE search was performed, using the terms congestive heart failure (CHF), gastric lavage, colonoscopy, irrigation, and gastroparesis, of English-language articles published from January 1980 through January 1995, as well as review of pertinent articles' bibliographies. CASE SUMMARY: A 45-year-old white woman with left ventricular systolic dysfunction and diabetic gastroparesis received 4 L of a PEG-ELS as preparation for colonoscopy. Within 24 hours she presented to the emergency department with shortness of breath and increased bilateral lower extremity edema. She was admitted and treated with intravenous furosemide therapy. After aggressive diuresis her symptoms returned to baseline and she was discharged. DISCUSSION: The literature search revealed no report of a patient requiring hospitalization as a result of sodium and water retention after bowel preparation with PEG-ELS. CHF is not considered a contraindication to the use of this solution; however, most studies that included patients with heart failure did not describe the degree of left ventricular dysfunction. Our patient's severe CHF, in combination with chronic renal insufficiency, resulted in significant retention of sodium and water. CONCLUSIONS: Patients with severe left ventricular dysfunction and chronic renal insufficiency who are being considered for procedures that necessitate bowel cleansing with PEG-ELS may be at risk for sodium and water retention and exacerbation of CHF.

Electrolytes↗
PubMed1994

Scintigraphic flare in skeletal lymphoma.

The authors describe the bone scan flare phenomenon in a patient with treated skeletal lymphoma. This was confirmed by both gallium scanning and computed tomography. If serial bone scintigraphy is used for assessing the treatment response of lymphoma, the flare phenomenon must be recognized.

Adult↗
PubMed1994

Doppler sonography of adnexal masses: the predictive value of the pulsatility index in benign and malignant disease.

OBJECTIVE: The purpose of this study was to determine whether pulsed Doppler sonography can be used to distinguish between benign and malignant adnexal masses on the basis of pulsatility index. SUBJECTS AND METHODS: In an 18-month period, all patients in whom an adnexal mass was detected at sonography had further evaluation of the mass by color and pulsed Doppler sonography. Ninety-nine patients with 102 masses that were surgically removed were included in the study. The pulsatility indexes were calculated from the reproducible spectral waveforms generated from flow centrally or peripherally within or immediately adjacent to the mass. Each lesion was categorized on the basis of its gray scale morphologic features as typically benign or indeterminate/malignant in appearance. RESULTS: Of the 102 adnexal masses, 89 were benign and 13 were malignant. In seven of the 89 benign lesions, no flow could be detected, and these were excluded from analysis. Of the remaining 82 benign lesions, 65 showed pulsatility indexes consistently equal to or greater than 1.0, and 17 showed pulsatility indexes of less than 1.0. Ten of the 13 malignant lesions had pulsatility indexes consistently less than 1.0, and three primary malignant tumors had their lowest pulsatility indexes ranging between 1.1 and 1.8. Sixty-five of the 68 masses with pulsatility indexes equal to or greater than 1.0 were benign, for a positive predictive value of 96% for benign disease. Ten of the 27 masses with pulsatility indexes of less than 1.0 were malignant, for a positive predictive value of 37% for malignant disease. Forty-five masses were detected in perimenopausal and postmenopausal patients. In this group, the pulsatility index had a positive predictive value of 88% for benign disease and 47% for malignant disease. In this study, 45 of 49 masses that had a typically benign sonographic appearance had pulsatility indexes equal to or greater than 1.0. All 49 masses had benign histology. In the remaining 46 masses with an indeterminate/malignant sonographic appearance, 20 of 23 with pulsatility indexes equal to or greater than 1.0 were benign, and 10 of 23 with pulsatility indexes of less than 1.0 were malignant. CONCLUSION: Our results show a high positive predictive value of high-impedance flow in benign adnexal disease and a predominance of low-impedance flow in malignant adnexal disease. However, the pulsatility indexes showed considerable overlap between benign and malignant lesions, indicating that Doppler sonography has severe limitations in the differentiation of benign from malignant adnexal disease on the basis of low-impedance flow (pulsatility index < 1.0).

Adenofibroma↗
PubMed1994

Levonorgestrel implants as a contraceptive in captive white-tailed deer.

Silastic implants containing levonorgestrel (LNG) were evaluated as a contraceptive in captive white-tailed deer (Odocoileus virginianus). Six adult females and six female fawns received either six or nine implants in autumn. Each implant contained 36 mg of LNG. Blood was analyzed by radioimmunoassay to determine LNG release profile for 5 mo post-implantation. Serum LNG concentrations rose significantly (P = 0.0005) 3 days post-implantation, leveled off after 7 days, and did not change (P = 0.5913) during the remaining 5 mo. Mean (+/- SE) LNG concentrations for all months were higher (P = 0.0377) in adult and fawn females implanted with nine versus six rods (138.1 +/- 14.4 versus 56.7 +/- 12.3 pg/ml, respectively). Serum LNG levels did not differ between adults and fawns. Five of the six implanted adult females had normal estrous cyclicity; three of these five adult females became pregnant in the first year. Four implanted females (two yearlings and two adults) were monitored during a second year, and housed with a fertile buck; three of them became pregnant. We do not recommend the use of LNG in deer.

Animals↗
PubMed1993

Effect of exposure to low level lead on growth and growth hormone release in rats.

This study was undertaken to examine the effect of exposure to low level lead on growth and growth hormone (GH) release. Female pups exposed to lead beginning in utero were smaller than controls on postnatal day 7 (P = 0.06). There was no corresponding effect in males. No overall differences in body weights were detected in either sex with respect to treatment effect. No differences in food or water intake were observed at any time. Pituitaries from 49-day-old lead-treated pups responded to in vitro incubation with growth hormone releasing factor (GRF) with a smaller increase in GH release than those from control pups (P = 0.08). In the case of the dams, lead did not affect body weight, body length, food consumption or pituitary responsiveness; however, water consumption was significantly increased in the lactating dam (P < 0.05). Interestingly, blood lead content in 5-day-old pups (43.3 +/- 2.7 micrograms/dl) exposed to lead in utero was more than twice that of their 49-day-old litter-mates (18.9 +/- 0.7 micrograms/dl). At 49 days blood lead levels in female pups (19.94 +/- 0.8 micrograms/dl) were significantly higher than those of male pups (17.00 +/- 1.1 micrograms/dl). Maternal blood lead levels on the same day averaged 22.7 +/- 2.5 micrograms/dl. This study suggests that exposure to a low level of lead can reduce pituitary responsiveness to a hypothalamic stimulus. In addition, the data reinforce the importance of considering age and sex when evaluating the toxic effects of lead.

Animals↗
PubMed1991

Brain acetylcholinesterase activity in forest songbirds exposed to a new method of UULV fenitrothion spraying.

Brain acetylcholinesterase (AChE) activity was measured in forest songbirds exposed to Ultra Ultra Low Volume (UULV) aerial spraying of fenitrothion in New Brunswick for spruce budworm control. Brain AChE activity was determined in 324 songbirds from the sprayed blocks and 47 from an unsprayed control area, and represented four species. In most cases, more than half of the individuals of any species sampled were diagnosed as "exposed" (greater than or equal to 20% inhibition) to the fenitrothion sprays and had a mean percent level of inhibition of 40% or greater, relative to mean control values. The proportion of birds with life-threatening levels of inhibition (greater than or equal to 50%) was usually less than 20%. The largest proportion of birds with life-threatening inhibition was found after the first 210 g AI/ha spray. The White-throated Sparrow had the highest proportion (25-55%) of individuals with life-threatening inhibition after all sprays. Brain AChE inhibition was greater in exposed birds collected after the first 210 g AI/ha spray than after the second one. Variation among species' responses to the sprays is discussed in relation to habitat and foraging preferences. Several sampling biases which may contribute to underestimation of the impact of fenitrothion spraying on birds are identified.

Acetylcholinesterase↗
PubMed1991

Acute effects of a pedicled omental graft on cold-induced brain oedema in cats.

When used as a prophylactic measure and in chronic experiments, omental transposition has been shown to reduce ischaemic and traumatic oedema in the spinal cord and ischaemic oedema in the brain. We designed this experiment to evaluate the acute effects of a pedicled omental graft on cold-induced brain oedema in cats. Focal oedema was induced in the left frontoparietal region of the brain of nine anaesthetized cats. In five cats, a laparotomy was done and a pedicled omental graft was placed on the lesioned left hemisphere immediately after the cold lesion was made. All cats were sacrificed 72 hours later, and the water content of the white matter was determined in the lesioned and the normal hemispheres. The mean water content of the lesioned hemisphere of the treated group of animals was not significantly different from that of the control group. We conclude that a pedicled omental graft failed to reduce vasogenic oedema in an acute model and probably has no role in the acute management of brain oedema.

Animals↗
PubMed1991

Effect of lead on TRH and GRF binding in rat anterior pituitary membranes.

The effect of lead on binding of the hypothalamic peptides thyroid releasing hormone (TRH) and growth hormone releasing factor (GRF) to rat anterior pituitary receptors was examined in this study. Concentrations of lead ranging from 0.01 to 1 microM did not alter [3H]TRH binding; concentrations above 1 microM increased TRH association with pituitary receptors. A previously uncharacterized ligand, [125I]GRF (human 1-44 amide), was used to examine the binding of GRF to anterior pituitary receptors. A high affinity site (GRFH = 18.1%, KH = 11.5 pM) was displaced by human growth hormone releasing factor (hGRF) (1-44)-NH2 or hGRF (1-29)-NH2 but not by rat growth hormone releasing factor (rGRF) (1-29)-NH2. Use of this ligand also revealed a class of low affinity binding sites (GRFL = 81.9%, KL = 0.39 microM) which has not been previously described. The low affinity site could be displaced by hGRF (1-44)-NH2, hGRF (1-29)-NH2 and rGRF (1-29)-NH2. A synthetic growth hormone releasing peptide (GHRP) also interacted with the low affinity GRF binding site. Lead dose-dependently displaced the binding of [125I]GRF to its pituitary receptors. The IC50 of lead for inhibiting [125I]GRF binding was 0.195 mM added lead or 52 pM free lead. These data suggest that one mechanism by which lead may affect pituitary function is through inhibition of receptor binding.

Animals↗
PubMed1991

Simultaneous immunohistochemical detection of IUdR and BrdU infused intravenously to cancer patients.

Cell cycle kinetics of solid tumors in the past have been restricted to an in vitro labeling index (LI) measurement. Two thymidine analogues, bromodeoxyuridine (BrdU) and iododeoxyuridine (IUdR), can be used to label S-phase cells in vivo because they can be detected in situ by use of monoclonal antibodies (MAb) against BrdU (Br-3) or IUdR (3D9). Patients with a variety of solid tumors (lymphoma, brain, colon cancers) received sequential intravenous IUdR and BrdU. Tumor tissue removed at the end of infusion was embedded in plastic and treated with MAb Br-3 and 3D9 sequentially, using a modification of a previously described method. Clearly single and double labeled cells were visible, which enabled us to determine the duration of S-phase (Ts) and the total cell cycle time (Tc), in addition to the LI in these tumors. Detailed control experiments using tissue culture cell lines as well as bone marrow cells from leukemic patients are described, including the comparison of this double label technique with our previously described BrdU-tritiated thymidine technique. We conclude that the two methods are comparable and that the IUdR/BrdU method permits rapid and reliable cell cycle measurements in solid tumors.

Antibodies, Monoclonal↗
PubMed1990

Vaccination with membrane-associated idiotype provides greater and more prolonged protection of animals from tumor challenge than the soluble form of idiotype.

The purpose of this work was to compare the efficacy of immunizing mice with a soluble vs a cell-associated form of a tumor Ag. A murine B cell tumor (2C3), which displays an Id on its cell surface, grows progressively and gives rise to Id-negative tumor variants in nonimmunized animals. We previously reported that the tumor variants arise as a consequence of Id-specific T cell suppression of the Id+ tumor. The Id-specific effector T cells are CD4+, CD8-. Based upon these findings vaccination protocols have been designed and tested to determine whether the expansion of tumor-specific effector T cells would eliminate the Id+ tumors and prevent the subsequent generation of Id- tumor variants in vivo. MHC-restricted T cells typically recognize soluble Ag subsequent to modification by an APC, and APC may ultimately express a processed form of the Ag that is different from that expressed on the surface of the tumor cells. Based upon this assumption, the efficacy of immunizing mice with cell-associated 2C3 Id was compared to immunization with a soluble form of the same Id. Mice were immunized with either irradiated 2C3 cells or syngeneic spleen cells to which 2C3 protein was covalently linked. These immunization protocols provided a complete and lasting protection against a tumor challenge of up to 1 x 10(6) tumor cells. In contrast, most mice hyperimmunized with a soluble form of the Id did not survive this level of tumor challenge in spite of the production of significant levels of anti-Id antibodies. Mice immunized with the soluble form of the Id, which did survive, produced slowly progressing tumors expressing a 1000-fold less of the marker Id. These results illustrate the importance of understanding and properly exploiting a host's natural response to a tumor-specific Ag when designing effective immunization protocols for cancer therapy.

Animals↗