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K Gregory

Publications and source records attributed to K Gregory.

At least 19 recordsLinked to original sources
PubMed2001

Obstetrician-gynecologists' knowledge and training about antenatal corticosteroids.

OBJECTIVE: To characterize the clinical decisions, knowledge, opinions, and education of obstetricians and gynecologists about antenatal corticosteroids. METHODS: Questionnaires mailed to 1020 ACOG Fellows included items on demographics, knowledge, clinical practice patterns, and educational background regarding antenatal corticosteroids. RESULTS: The survey response rate was 47.8%. Almost all respondents (94%) reported administering antenatal corticosteroids, with reduction of respiratory distress syndrome (82%) as the primary reason for antenatal corticosteroid administration. Most (59.2%) were unaware of newly recognized associations between multiple administrations of corticosteroids and fetal growth restriction. In hypothetical clinical situations, responses by physicians who completed their residency training before 1970 indicated less likelihood to administer corticosteroids when administration is relatively indicated per National Institutes of Health (NIH) and ACOG guidelines than those trained later (P <.001). Only 8% of the entire sample rated their knowledge of antenatal corticosteroids as comprehensive; most (68%) rated it as adequate. Respondents rated residency training as a much better source of antenatal corticosteroid knowledge than medical school. CONCLUSION: Most obstetrician-gynecologists reported using antenatal corticosteroids; however, in general, many were not aware of more recent information regarding potential risks. This survey suggests that a multipronged educational approach is warranted to update obstetrician-gynecologists about antenatal corticosteroids.

Adult↗
PubMed2001

Premature rupture of the membranes: an evidence-based approach to clinical care.

Management of the patient with premature rupture of membranes is a relatively common but often perplexing problem frequently faced by the obstetrician. Despite the recent advances in perinatal care, premature membrane rupture, especially in the preterm patient, remains a potentially serious complication with important maternal and fetal implications. This review will address the important questions concerning the management of premature rupture of membranes and will attempt to provide comprehensive answers as they appear in the medical literature.

Adrenal Cortex Hormones↗
PubMed2000

Femur length and trisomy 21: impact of gestational age on screening efficiency.

OBJECTIVE: This study assesses two methods used to define relatively short femur in screening for trisomy 21 and examines changes in performance of screening with gestational age. DESIGN: Retrospective analysis of data on menstrual age, femur length (FL) and biparietal diameter (BPD) in 49 trisomy 21 pregnancies and 6069 normal controls. Reference ranges were derived for BPD/FL versus menstrual age and for FL versus BPD. Two methods of defining short femur (BPD/FL and observed-to-expected FL ratio) were examined for false-positive rates and detection rates for trisomy 21 at different gestational ages. RESULTS: In the control group the BPD/FL ratio and its standard deviation decreased with menstrual age. Trisomy 21 was associated with a significantly higher BPD/FL ratio (P < 0.001) and the deviation increased significantly with menstrual age (P < 0.05). Eleven percent of 28 fetuses examined at 15-17 weeks had a BPD/FL above the 95th centile compared with 24% of 21 fetuses examined at 18-20 weeks (P = 0.40). The median observed-to-expected FL ratio in the control group was 1.0 throughout the gestational age range but the standard deviation decreased significantly with menstrual age (P < 0.01). Trisomy 21 was associated with a significantly reduced observed-to-expected FL ratio (P < 0.001) and the deviation increased significantly with menstrual age (P < 0.05). A fixed cut-off of 0.91 for observed-to-expected FL ratio provided a false-positive rate of 12% at 15-17 weeks compared with 6% at 18-20 weeks of gestation (P < 0.001) with detection rates of 29 and 38%, respectively (P = 0.73). CONCLUSION: Irrespective of the definition used to define the condition, relatively short femur is a poor marker for trisomy 21 particularly when the assessment takes place before 18 weeks of gestation.

Adult↗
PubMed2000

A randomized phase II study of SRL172 (Mycobacterium vaccae) combined with chemotherapy in patients with advanced inoperable non-small-cell lung cancer and mesothelioma.

Mycobacterial preparations have been used with limited success against cancer apart from superficial bladder cancer. Recently, a therapeutic vaccine derived from Mycobacterium vaccae has been given to patients with prostate cancer and melanoma indicating a possible beneficial effect on disease activity in such patients. We have recently initiated a series of randomized studies to test the feasibility and toxicity of combining a preparation of heat-killed Mycobacterium vaccae (designated SRL172) with a multidrug chemotherapy regimen to treat patients with inoperable non-small cell lung cancer (NSCLC) and mesothelioma. 28 evaluable patients with previously untreated symptomatic NSCLC and mesothelioma were randomized to receive either 3 weekly intravenous combination chemotherapy alone, or chemotherapy given with monthly intra-dermal injections of SRL172. Safety and tolerability were scored by common toxicity criteria and efficacy was evaluated by survival of patients and by tumour response assessed by CT scanning. The toxicity of chemotherapy was similar in the two groups. SRL172 caused mild inflammation at the injection site. In the group of patients randomized to receive chemotherapy combined with SRL172, there was a trend towards improved response rate (54% vs. 33%) with more patients in the combined arm receiving radical surgery and radiotherapy, improved median survival (9.7 months vs. 7.5 months) and improved 1 year survival (42% vs. 18%). SRL172 appeared to improve sleep (P = 0.08) and improved appetite (P = 0.01). There was no detectable change in serum cytokine levels for gamma-interferon and TNF-alpha before and after treatment. In patients with NSCLC and mesothelioma, there may be a beneficial interaction when chemotherapy is administered in combination with SRL172. Confirmation of this effect and further investigation is underway in a randomized phase III trial and in laboratory models.

Adjuvants, Immunologic↗
PubMed2000

Nurse the patient!

Explore the source record for details and available documents.

Clinical Competence↗
PubMed1998

Hysterectomy in a decade of change: more than a weighty matter.

Objective: Hysterectomy is the second most common surgical procedure performed in the United States. Interest to decrease use of hysterectomy has focused on developing explicit criteria for surgery, peer review and second opinion, as well as changing reimbursement incentives. The purpose of this study is to describe the change in the number of hysterectomies, the indications for hysterectomies, and the histopathology of hysterectomy specimens over the last 10 years at one private, nonprofit, academic, community hospital that does not have a formal system for monitoring hysterectomy use.Methods: Retrospective study utilizing administrative data matched with pathology reports for nonmalignant hysterectomies performed in 1985, 1990, and 1995. Uterine weight and histopathologic diagnoses were recorded. When pathology reports were unavailable, cases were reviewed to determine if the indication was related to prolapse or urinary incontinence. Outcome measures included number of procedures performed, indications for procedures and uterine pathology (uterine weight, histopathology). We utilized the Cochran-Mantel-Haenszel chi(2) and the Kruskal-Wallis rank sum statistic (P <.05).Results: The number of hysterectomies declined from 631 in 1985 to 461 in 1995 (P =.007). The median uterine weight increased (P =.0007), and there was a decrease in the number of specimens with absent histopathology, decreasing from 6% in 1985 to 3% in 1995 (P =.013). This difference was explained by changes in the number of procedures performed on patients with private insurance and HMO reimbursement (P =.018).Conclusions: While the proportion of surgeries performed for specific indications did not change, the number of hysterectomies performed decreased, and there were fewer normal specimens.

Journal Article↗
PubMed1996

Periodontal status of diabetic and non-diabetic men: effects of smoking, glycemic control, and socioeconomic factors.

Periodontal disease is more prevalent and more severe in diabetic than in non-diabetic individuals but the magnitude of this increase is still being debated. This prospective, cross-sectional study compared the periodontal status of 118 diabetic men and 115 age-matched non-diabetic men. Plaque and gingival indices, bleeding scores, probing depth, loss of attachment, and number of missing teeth were measured in a blinded manner. Smoking status, glycemic control, socioeconomic status, and previous dental care were also assessed. These parameters were significantly higher in diabetic than non-diabetic men: plaque index, P < 0.0001; gingival index, P < 0.0002; bleeding score, P < 0.0001; probing depth, P = 0.0059; loss of attachment, P < 0.0001; and missing teeth, P < 0.005. These parameters were significantly higher in smokers than non-smokers: gingival index, probing depth, and loss of attachment. The duration of diabetes was not significantly related to the periodontal measures. Glycemic control as assessed by fasting plasma glucose and glycohemoglobin values was not significantly correlated to periodontal status. These studies indicate, for this study group, that diabetes significantly affects all measured parameters of periodontal status.

Adult↗
PubMed1995

The outcome of macrosomic infants weighing at least 4500 grams: Los Angeles County + University of Southern California experience.

OBJECTIVE: To describe the maternal and neonatal outcome of macrosomic infants weighing at least 4500 g. METHODS: Maternal and neonatal records of infants with birth weights of at least 4500 g were identified during 1991. Outcome variables included the mode of delivery and incidence of maternal and perinatal complications. RESULTS: The study sample consisted of 227 infant and mother pairs. Mean (+/- standard deviation) birth weight was 4706 +/- 219 g. A trial of labor was allowed in 192 women, and elective cesarean delivery was performed in 35 patients. The overall cesarean rate, including elective cesarean delivery and failed trial of labor, was 30.8% (70 of 227). Of those undergoing a trial of labor, 82% (157) delivered vaginally. Shoulder dystocia occurred 29 times, for an incidence of 18.5% in vaginal deliveries for macrosomia. There were seven cases each of Erb palsy and clavicular fracture, and one humeral fracture. By 2 months of age, all affected infants were without permanent sequelae. There was no birth asphyxia or perinatal mortality related to delivery for macrosomia. Maternal complications included increased risk of lacerations requiring repair (especially third- or fourth-degree lacerations) when vaginal delivery was complicated by shoulder dystocia (relative risk [RR] 5.4, 95% confidence interval [CI] 3.1-9.4). There was no statistically significant difference with respect to hemorrhage or hospital stay for women who had a vaginal delivery (with or without shoulder dystocia) compared with women who had a cesarean delivery. However, infectious morbidity increased significantly in those patients who underwent a cesarean after a trial of labor compared with women who had a vaginal delivery (RR 7.1, 95% CI 3.9-13.1) or elective cesarean birth (RR 5.4, 95% CI 3.1-9.4). Ninety-one percent of patients undergoing elective cesarean delivery had no complications. CONCLUSION: Vaginal delivery is a reasonable alternative to elective cesarean for infants with estimated birth weights of at least 4500 g, and a trial of labor can be offered.

Adolescent↗
PubMed1995

An identified glutamatergic interneuron patterns feeding motor activity via both excitation and inhibition.

1. Previously we demonstrated that glutamate is an important neurotransmitter in the CNS of Helisoma. Exogenous glutamate applied to the buccal ganglia mimicked both the excitatory and inhibitory effects of subunit 2 (S2) of the tripartite central pattern generator (CPG) on S2 postsynaptic motor neurons. Here we identify buccal interneuron B2 as an S2 interneuron by utilizing a combination of electrophysiology, pharmacology, and intracellular staining. In addition, neurons that were electrophysiologically and morphologically characterized as neuron B2 demonstrated antiglutamate immunoreactivity, suggesting that neuron B2 is a source of endogenous glutamate in the buccal ganglia. 2. Depolarization of neuron B2 evoked excitatory postsynaptic potentials in motor neurons excited by S2. The excitatory effects of B2 depolarization and S2 activation were reversibly antagonized by the ionotropic glutamate receptor antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione, similar to the antagonism shown previously for application of exogenous glutamate. Depolarization of neuron B2 also evoked inhibitory postsynaptic potentials in motor neurons inhibited by S2. When such motor neurons were maintained in isolated cell culture, application of exogenous glutamate produced a direct hyperpolarization of the membrane potential. 3. The activity of neuron B2 is necessary for the production of the standard pattern of buccal motor neuron activity, which underlies functional feeding movements. The subunits of the tripartite buccal CPG must be active in the temporal sequence S1-S2-S3 to produce the standard feeding pattern. Rhythmic inhibition from neuron B2 terminated activity in S1 postsynaptic motor neurons and entrained the frequency of activity in S3 postsynaptic motor neurons. Hyperpolarization of neuron B2 disrupted the production of the standard motor pattern by eliminating S2 postsynaptic potentials in identified buccal motor neurons, thereby prolonging S1 activity and disrupting S3 bursting. 4. These data support the hypothesis that S2 neuron B2 is glutamatergic and demonstrate that glutamatergic transmission, and especially inhibition, is fundamental to the production of behaviorally critical motor neuron activity patterns in Helisoma.

6-Cyano-7-nitroquinoxaline-2,3-dione↗
PubMed1993

Relaxation of vascular smooth muscle induced by low-power laser radiation.

The relaxation of rabbit aorta rings induced by low-power laser radiation was investigated in vitro to determine the location of the chromophore(s) responsible for this response and evaluate possible mechanisms. An action spectrum for relaxation was measured on rabbit thoracic aorta rings precontracted with norepinephrine. The decrease in isometric tension was measured during exposure to laser light (351-625 nm) delivered via a fiber optic to a small spot on the adventitial surface. The shortest UV wavelength (351 nm) was 35-fold more effective than 390 nm and 1700-fold more effective than 460 nm. Ultraviolet wavelengths also produced greater maximum relaxation (0.40-0.45) than visible wavelengths (0.20-0.25), suggesting that photovasorelaxation involves more than one chromophore. The adventitial layer was not necessary for photovasorelaxation, indicating that the light is absorbed by a chromophore in the medial layer. The same degree of relaxation was obtained on rings without adventitia when either one-half of the ring, or a small spot was irradiated indicating that communication between smooth muscle cells spreads a signal from the area illuminated to the entire ring. The mechanism for photovasorelaxation was investigated using potential inhibitors. N-monomethyl-L-arginine and N-amino-L-arginine, inhibitors of nitric oxide synthase, did not alter photovasorelaxation nor did indomethacin, an inhibitor of cyclooxygenase, and zinc protoporphyrin, an inhibitor of heme oxygenase.

Animals↗
PubMed1993

Evaluation of routine diabetes and lipid screening after age 35 in candidates for or current users of oral contraceptives.

OBJECTIVE: To evaluate the efficacy of a diabetes and lipid screening program in women aged 35 or older who either were currently using a low-estrogen-dose oral contraceptive (OC) (0.03-0.04 ethinyl estradiol) or who desired to initiate low-dose OC therapy after using a non-OC method or following a recent pregnancy. METHODS: Healthy women with no history of abnormal glucose tolerance, hypertension, or hyperlipidemia aged 35 years and older were routinely screened for diabetes (fasting and 2-hour values after 75 g glucose) and dyslipidemia (fasting total cholesterol, high-density lipoprotein [HDL] and low-density lipoprotein [LDL] cholesterol, and triglycerides). Three groups of women were studied: women currently using low-dose OCs (OC group), women desiring to change to OC therapy (non-OC group), and women within 3 months post-pregnancy (postpartum group). RESULTS: The three groups were similar in age, parity, body mass index (BMI), and mean arterial pressure. The mean months of contraceptive use were not different between the OC group (30.2 months; 95% confidence interval [CI] 26.6-33.8) and the non-OC group (38.4 months; 95% CI 32.0-44.8). The mean fasting serum glucose, after adjusting for age and BMI, was significantly lower in the OC group (82.4 +/- 9.4 mg/dL) than in the non-OC and postpartum groups (87.2 +/- 12.5 and 86.8 +/- 13.0 mg/dL, respectively; P = .01). After adjustments, no differences between the groups were found in the 2-hour post-glucose levels, triglycerides, or HDL or LDL cholesterol levels. The non-OC group was found to have a significantly lower total cholesterol level (188.7 +/- 32.4 mg/dL) than the OC and postpartum groups (202.7 +/- 38.1 and 204.4 +/- 41.0 mg/dL; P = .02) after adjusting for age and BMI. This association lost its significance after applying multiple range tests, maintaining an alpha error of 0.05. CONCLUSION: The absence of significant adverse metabolic markers in longer-term OC users over the age of 35, in comparison to similar-age control groups, does not support the routine use of lipid and diabetes screening before initiating or during the use of low-dose OCs.

Adult↗
PubMed1992

Removal of retained intrauterine contraceptive devices in pregnancy.

Using real-time ultrasound and clinical expertise gained from chorionic villus sampling, we describe a technique for ultrasound-guided intrauterine device removal in those cases in which the string is not visible. Utilizing a stone clamp for intrauterine manipulation, we were easily able to extract the device without interrupting the pregnancy. We concur with recent recommendations advocating all intrauterine devices can be removed if pregnancy termination is declined.

Adult↗
PubMed1991

Optical coherence tomography.

A technique called optical coherence tomography (OCT) has been developed for noninvasive cross-sectional imaging in biological systems. OCT uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue microstructures in a way that is analogous to ultrasonic pulse-echo imaging. OCT has longitudinal and lateral spatial resolutions of a few micrometers and can detect reflected signals as small as approximately 10(-10) of the incident optical power. Tomographic imaging is demonstrated in vitro in the peripapillary area of the retina and in the coronary artery, two clinically relevant examples that are representative of transparent and turbid media, respectively.

Coronary Disease↗
PubMed1990

Beyond drug effects and dependent variables: the use of the Poisson-Erlang model to assess the effects of D-amphetamine on information processing.

Several studies have shown that d-amphetamine (DAMP) speeds mean reaction time (RT). However, the use of mean RT may obscure important aspects of the drug response. Therefore we applied the Poisson-Erlang (PE) stochastic model of choice reaction time proposed by Pieters (1985) to the RT distribution. This model proposes that the RT distribution is generated by two states: Processing (P) and Distraction (D). RT represents the sum of the time spent in each of these states. P is the time taken to complete a set of cognitive operations which are required to give a correct response. D represents the time taken by all other activities. RTs were collected using a task (SERS) in which stimulus and response complexity each had two levels, easy and hard. Subjects were tested pre- and postdrug. Drug conditions were: placebo, 10 mg d-amphetamine (DAMP), 4 mg of the dopamine agonist, pimozide, and a combination of DAMP and pimozide (COMBO). Parameters of the model were derived using methods described by Pieters. Four measures were analyzed: Processing Time (PT); Mean Time per distraction (XTD); Distraction Rate (DR); and Total Distraction Time per trial (TDT). Mean RT is also presented. Analyses of the effects of task conditions on the parameters of the model were made using the predrug sessions. Mean RT was increased by both stimulus and response complexities as was PT. TDT was increased by the task conditions. The PE measures did not change over days. DAMP speeded mean RT. However, this effect did not interact with the task factors. DAMP speeded processing and reduced distraction. Processing was speeded only in the hard response condition, distraction time was reduced only in the easy response condition. The results indicate that the PE model can be successfully applied to fast RT tasks. More importantly, the parameters of the model revealed important pharmacological effects that were not apparent in mean RT. DAMP speeds cognitive operations related to motor preparation and reduces the effects of distraction. Consistent with past studies there are no indications that DAMP interacted with stimulus processing. The distraction effect appears to be mediated by an increase in the rate of distraction and a decrease in the average time of these distractions.

Adult↗
PubMed1990

Self-generated mnemonics for enhancing free recall performance in older learners.

The effectiveness of self-generated mnemonic strategies for free-recall list learning was examined in 94 older community-dwelling adults. Participants were presented with a list of 19 nouns and were given seven minutes to commit the list to memory with three minutes for recall. Performance was measured immediately following recall and after a 2-day delay. Forty-five percent of the participants reported using a specific organizational mnemonic encoding strategy to facilitate recall. At both immediate and delayed recall, those individuals who reported using a well-articulated mnemonic outperformed those reporting the use of repetition or making simple associations. The results suggest that many older adults can spontaneously generate specific elaborative encoding strategies and that pre-existing encoding skills should be assessed prior to remedial memory training for older adults.

Aged↗
PubMed1987

Medical students' expectations for encounters with minority and nonminority patients.

The authors examined the expectations of firstyear medical students (n = 139) at the University of California, Los Angeles, School of Medicine in regard to interacting with black, Latino, Asian, and white patients. Using slides and a questionnaire, the results indicated that students expected to be significantly less comfortable interviewing blacks than other patients and to view blacks and Latinos as less likely to comply with treatment than whites and Asians. Black and Hispanic students were significantly more likely than white and Asian students to expect black and Hispanic patients to comply with treatment.

Adolescent↗