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The survival for patients with advanced breast cancer following conventional combination chemotherapy remains limited. Attempts to circumvent drug resistance have involved high-dose chemotherapy along with autologous hematopoietic stem cell support. Despite this, relapse remains the primary cause of death. Breast tumor cells are commonly found in hematopoietic stem cell collections. The role of reinfused occult tumor cells in malignant relapse following high-dose chemotherapy has yet to be determined but is likely to have a negative impact. Strategies to decrease stem cell contamination under investigation include: (1) improved regimens for stem cell mobilization, (2) enhanced techniques for tumor cell detection, (3) targeted tumor cell purging and (4) alternative sources of stem cells. These approaches hold promise for improving the outcome of patients undergoing high-dose chemotherapy and stem cell reinfusion for poor-prognosis breast cancer.

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Expansion of the preadmission process for same-day-admit (SDA) surgery patients through our Admissions Evaluation Center has provided an efficient and convenient means for complete patient evaluation up to 30 days in advance of surgery. Traditionally, collection of blood samples for the pretransfusion testing that is necessary to select compatible blood for transfusion occurs within 72 hours of admission, consistent with standards to ensure detection of red blood cell (RBC) alloantibodies formed as a result of recent transfusion or pregnancy. As a result, samples for many SDA patients were submitted Stat the morning of surgery, resulting in an unwieldy amount of testing and delay in blood availability. To address this problem, the time interval for collection of patient blood samples for pretransfusion testing was extended to 30 days prior to surgery. To ensure safety, this change required documentation of patient transfusion and pregnancy history at 2 specific timepoints. Input from a multidisciplinary team was vital to assess the process of blood ordering and administration and to determine the best means to accomplish these steps. Implementation of the new process resulted in a decreased number of emergent requests for compatibility testing, decreased delays in blood delivery, and elimination of canceled surgery due to cases with unexpected RBC antibodies.

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We describe the successful treatment of a pregnant patient with chronic myelogenous leukemia in chronic phase by using only leukapheresis. Following 20 leukapheresis procedures initiated during the 13th week of gestation and performed over approximately 7 weeks, the patients white blood cell count dropped from 242,000/microl to 19,300/microl. The WBC remained stable over the ensuing 17 weeks until the time of delivery. The patient gave birth by cesarean section to a healthy 2,640 g boy at 37.5 weeks of gestation. This is the second report of the successful use of leukapheresis alone for chronic myelogenous leukemia in chronic phase during the first half of pregnancy. We conclude that where leukapheresis is available, it may provide an alternative treatment to chemotherapy or alpha-interferon, especially in light of their potential teratogenic and leukemogenic side-effects.

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The preovulatory luteinizing hormone (LH) surge results from the integration of complex interactions among gonadal steroids and hypothalamic and pituitary hormones. To evaluate changes in LH secretory dynamics that occur during the rat LH surge, we have 1) obtained frequently sampled serum LH concentration time series, 2) used both waveform-dependent and waveform-independent convolution analyses, and 3) independently assessed proestrous LH half-life and basal non-gonadotropin-releasing hormone (GnRH)-dependent LH secretion during the LH surge. Waveform-independent pulse analysis revealed a 24-fold increase in the maximal pulsatile LH secretory rate attained during late proestrus compared with early proestrus. A 15-fold increase was quantified for the mean LH secretory rate. In complementary analyses, we applied a measured LH half-life of 17 +/- 2.7 min and a median basal LH secretion rate of 0.0046 microgram. l-1. min-1 for convolution analysis, revealing a 16-fold increase in the mass of LH released/burst and more than sixfold rise in the amplitude of the secretory peaks. Evaluation of the approximate entropy of the LH surge profiles was performed, showing an increase in the orderliness of the LH release process during the surge. We conclude that both quantitative (mass/burst) and qualitative (approximate entropy) features of LH release are regulated during the proestrous LH surge.

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OBJECTIVE: To evaluate a modification of a commercially available reagent kit (COATEST APC Resistance Kit) for functional activated protein C (APC) resistance testing, and to determine the ability of the modified assay to demonstrate APC resistance in patients receiving warfarin. DESIGN: Functional APC resistance testing was performed using both the first-generation COATEST APC Resistance Kit and a modified, or second-generation, version of the COATEST assay that uses predilution of the patient sample with factor V-deficient plasma. Factor V genotyping for APC resistance (FV R506Q) was performed using a well-characterized polymerase chain reaction-restriction fragment length polymorphism method. SETTING: University medical center. PATIENTS: Seventy-three individuals referred for hypercoagulability testing who were not receiving warfarin therapy and 29 patients with a history of venous thrombosis who were receiving warfarin therapy. MAIN OUTCOME MEASURE: Sensitivity and specificity as determined by comparing functional APC resistance to the FV R506Q genotype. RESULTS: In 73 patients referred for hypercoagulability testing, but not receiving warfarin therapy, a sensitivity of 0.86 and a specificity of 0.75 were obtained with the first-generation COATEST assay. In contrast, a sensitivity and specificity of 1.0 were obtained when the second-generation COATEST assay was employed. In 29 patients receiving warfarin, the first-generation assay exhibited a sensitivity and specificity of 0.88 and 0.95, respectively, whereas the sensitivity and specificity for the second-generation assay was 1.0. CONCLUSIONS: Predilution of patient plasma with factor V-deficient plasma results in improved sensitivity and specificity of the COATEST APC Resistance Kit, thus offering a simple modification to enhance APC resistance determination in the routine clinical laboratory setting.

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Peripheral administration of N-methyl-D,L-aspartate (NMA), an analogue of the excitatory amino acid aspartate, elicits LH and prolactin (PRL) release in rats, most likely by increasing endogenous releasing-hormone secretion. These experiments were carried out to assess the degree to which NMA stimulates FSH and to analyze the relationship between endocrine status and responsiveness to NMA in female rats, in contrast to male rats, as described in the companion paper [Biol Reprod 48:000-000]. In experiment 1, estrous rats (n = 10) and diestrous rats (n = 10) and in experiment 2, estrous rats (n = 11) and rats ovariectomized (OVX) 8 days previously (n = 10) were fitted with atrial catheters and injected s.c. with 100 micrograms of an LHRH antagonist or vehicle at 2100 h. Starting at 0900 h the next day (metestrus, proestrus, or Day 9 post-OVX), blood was withdrawn every 10 min for 3 h. Each animal received i.v. 5 mg NMA after the first hour and i.v. 500 ng LHRH after the second hour. NMA significantly increased LH in metestrous and proestrous females, and LHRH antagonist blunted the increases. In OVX females, LH decreased after NMA. FSH was not affected by NMA in any group. PRL increased after NMA in proestrous and metestrous animals. LHRH caused surge-like LH and small FSH increases in vehicle groups; these increases did not differ in amplitude between intact and OVX animals and were blunted by pretreatment with LHRH antagonist. In experiment 3, 10 diestrous rats were fitted with atrial catheters and were serially bled at 2-h intervals from 1200 h on the following day (proestrus) until 0600 h on estrus morning. After the first sample the animals were injected s.c. with 0.2 mg/kg MK801, a noncompetitive NMA receptor antagonist, or with saline. Four of the 5 saline-treated animals exhibited surges of LH and FSH as well as elevated progesterone levels, with LH and progesterone peaking at 2000 h. Five of 5 MK801-treated animals failed to have elevated LH, FSH, or progesterone levels at any time point. These data demonstrate that LHRH mediates the LH response to NMA in rats and that endogenous NMA receptor binding may be necessary for the preovulatory gonadotropin surges. The lack of FSH responses to NMA during periods of low-level gonadotropin secretion suggests that physiological increments in endogenous LHRH secretion sufficient to induce a pulse of LH are insufficient to stimulate pulse-like FSH release.(ABSTRACT TRUNCATED AT 400 WORDS)

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Peripheral administration of N-methyl-D,L-aspartate (NMA), a neuroexcitatory amino acid agonist, probably stimulates LH release through an increase in endogenous LHRH secretion. In the present study, NMA and a potent LHRH antagonist were used to determine the degree to which release of FSH is similarly dependent upon the acute secretion of LHRH. A second aim was to compare responsiveness of LHRH neurons to NMA in castrated and intact male rats. Adult male rats were castrated (n = 10) or sham castrated (n = 11) on the morning of Day 0. After 8 days, rats were fitted with atrial catheters between 0900 and 1200 h; at 2100 h they received s.c. either oil vehicle or 100 micrograms of an LHRH antagonist. Starting at 0900 h on Day 9, 0.5-ml blood samples were collected every 10 min for 3 h. After 1 h of sampling each animal received i.v. 5 mg of NMA in 0.5 ml 0.9% saline. An hour later each rat received i.v. 500 ng of LHRH in 0.5 ml saline. Plasma LH, FSH, and prolactin (PRL) levels were determined by RIA. In the oil-treated sham castrates, mean plasma LH levels were increased by 110% (p < 0.01) within 10 min and remained elevated for 30 min after the injection of NMA. The profile of this LH secretory response was similar to or slightly more robust than endogenous LH pulses observed previously. The NMA-induced LH release was completely blocked by pretreatment with LHRH antagonist. In both oil- and antagonist-treated sham-castrated rats, NMA administration failed to elicit a concomitant increase in plasma FSH levels.(ABSTRACT TRUNCATED AT 250 WORDS)

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We have analyzed the mechanisms by which several known regulators of the LHRH release process may exert their effects. For each, we have attempted to determine how and where the regulatory input is manifest and, according to our working premise, we have attempted to identify factors which specifically regulate the LHRH pulse generator. Of the five regulatory factors examined, we have identified two inputs whose primary locus of action is on the pulse-generating mechanism--one endocrine (gonadal negative feedback), and one synaptic (alpha 1-adrenergic inputs) (see Fig. 29). Other factors which regulate LHRH and LH release appear to do so in different ways. The endogenous opioid peptides, for example, primarily regulate LHRH pulse amplitude (Karahalios and Levine, 1988), a finding that is consistent with the idea that these peptides exert direct postsynaptic or presynaptic inhibition (Drouva et al., 1981). Gonadal steroids exert positive feedback actions which also result in an increase in the amplitude of LHRH release, and this action may be exerted through a combination of cellular mechanisms which culminate in the production of a unique, punctuated set of synaptic signals. Gonadal hormones and neurohormones such as NPY also exert complementary actions at the level of the pituitary gland, by modifying the responsiveness of the pituitary to the stimulatory actions of LHRH. The LHRH neurosecretory system thus appears to be regulated at many levels, and by a variety of neural and endocrine factors. We have found examples of (1) neural regulation of the pulse generator, (2) hormonal regulation of the pulse generator, (3) hormonal regulation of a neural circuit which produces a unique, punctuated synaptic signal, (4) hormonal regulation of pituitary responsiveness to LHRH, and (5) neuropeptidergic regulation of pituitary responsiveness to LHRH. While an attempt has been made to place some of these regulatory inputs into a physiological context, it is certainly recognized that the physiological significance of these mechanisms remains to be clarified. We also stress that these represent only a small subset of the neural and endocrine factors which regulate the secretion or actions of LHRH. A more comprehensive list would also include CRF, GABA, serotonin, and a variety of other important regulators. Through a combination of design and chance, however, we have been able to identify at least one major example of each type of regulatory mechanism.

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An in vivo isolated pituitary paradigm was used to examine the extent to which negative feedback actions of testicular hormones are exerted directly at the level of the anterior pituitary gland. Hypophysectomized male rats received single anterior pituitary transplants under the kidney capsule. On the next day each hypophysectomized, graft-bearing (H/G) animal was fitted with a concentric atrial catheter system which allowed for intermittent infusions of LHRH (250 ng/5 min.h) and chronic blood sampling. On the fifth or sixth day of infusions, blood samples were obtained 2 h before sham-castration (n = 6) or castration (n = 5) and at every 2-h interval for 24 h thereafter. For comparison, blood samples were similarly obtained from a group of normal pituitary-intact male rats before and after sham-castration (n = 5) or castration (n = 5). Plasma LH and PRL levels in all animals were determined by RIA. In the H/G sham-castrate rats, LH levels remained constant throughout the 24-h postsurgery period. By contrast, plasma LH concentrations in the H/G castrate rats increased steadily for 18 h, reaching a plateau at levels 2- to 3-fold higher than pretreatment values. The absolute amounts of immunoreactive LH, and the trajectory of the LH rise in the H/G castrates closely resembled those in the normal castrates during the initial 20 h after castration; at subsequent time points, however, these similarities were not apparent, as LH levels in normal castrates continued to rise, while those in H/G castrates did not. PRL levels were not significantly different in H/G rats compared to those in their pituitary-intact counterparts. We conclude from these studies that most of the acute (less than 20 h) effects of castration on LH secretion can be accounted for by pituitary escape from direct negative feedback suppression. At longer times after orchidectomy, however, the continued postcastration rise in LH secretion may increasingly depend upon additional hypothalamic input. It is hypothesized that this added input consists of an acceleration of LHRH pulse frequency.

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The differential feedback actions of estrogen (E2) on gonadotropin secretion were studied by means of an in vivo isolated pituitary paradigm. Adult female rats were hypophysectomized (hypox) and the next day received single anterior pituitary transplants (graft) under the kidney capsule. At the same time rats underwent bilateral ovariectomy. On the third day each animal was fitted with a catheter system which allowed for intermittent infusions of LHRH (250 ng/5 min.h) and chronic blood sampling. Rats received LHRH infusions for 7 days. On the sixth day of LHRH infusions blood samples were collected for 4 h 5, 15, 25, 35, 45 min after each hourly LHRH pulse. After 1 h of sampling, animals received sc injections of 2 micrograms estradiol benzoate (EB; n = 5) or oil vehicle (n = 5). Plasma LH, FSH, E2, and PRL levels in samples from all groups were determined by RIA. In hypox/graft rats LH release, but not FSH release, was pulsatile in response to the hourly LHRH infusions. Injection of EB in the hypox/graft rats significantly (P less than 0.05) suppressed LH release within 3 h by 57%, while FSH was unaffected. PRL levels were elevated by approximately 10-fold in the hypox/graft animals compared to those in pituitary-intact rats. These levels, however, were not changed as a function of steroid treatment and, therefore, could not account for the effects of EB on LH secretion. On the basis of these observations we conclude that 1) a major inhibitory effect of an acute injection of EB on LH secretion is exerted by a direct action on pituitary gonadotropes, and 2) E2 can differentially affect the release of LH and FSH by an intrapituitary mechanism. It is hoped that development of this model will allow for further investigation of the cellular mechanisms that mediate feedback actions of E2 on pituitary gonadotropes exposed to intermittent LHRH stimulation.

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