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D R Meldrum

Publications and source records attributed to D R Meldrum.

At least 19 recordsLinked to original sources
PubMed1992

Leuprolide acetate elevates prolactin during ovarian stimulation with gonadotropins.

OBJECTIVE: The purpose of this study was to determine whether gonadotropin-releasing hormone agonist further increases the prolactin rise accompanying ovarian stimulation. DESIGN: Serum prolactin concentrations were compared between cycles with and cycles without the use of leuprolide acetate (LA) matched for estradiol levels. Relationships of prolactin levels to cycle outcomes were examined. SETTING: The study took place at a private fertility center. PATIENTS: Patients were women receiving stimulation for oocyte retrieval using human menopausal gonadotropins. INTERVENTIONS: No interventions were used. MAIN OUTCOME MEASURES: Serum prolactin level, fertilization rate, embryo quality, and pregnancy were the main outcome measures. RESULTS: Higher serum prolactin was associated with both higher estradiol levels and use of LA but did not have any effects on fertilization rate, embryo quality, or occurrence of pregnancy. CONCLUSION: LA stimulates prolactin release during ovarian stimulation but without apparent consequence.

Chorionic Gonadotropin↗
PubMed1992

Ibuprofen restores cellular immunity and decreases susceptibility to sepsis following hemorrhage.

Although hemorrhage depresses splenocyte (SPL) functions and increases susceptibility to sepsis, it is not known whether increased tumor necrosis factor (TNF) or prostaglandin (PG) production are responsible for it. To study this, mice (C3H/HeN) were bled to a mean blood pressure of 35 mm Hg, maintained at that pressure for 60 min, resuscitated, and treated with ibuprofen (1.0 mg/kg body weight) or vehicle (saline). Hemorrhage reduced (P less than 0.05) SPL proliferation by 60%, SPL release of interleukin-2 (IL-2) by 47%, interferon-gamma (IFN-gamma) by 67%, TNF by 54%, and interleukin-6 (IL-6) by 46% compared to sham. In addition, splenic macrophage (sM phi) release of interleukin-1 (IL-1) and TNF was decreased by 58 and 67% (P less than 0.05), respectively. However, ibuprofen treatment increased (P less than 0.05) SPL proliferation, lymphokine (IL-2, IFN-gamma, and IL-6) synthesis, and IL-1 release by sM phi compared to hemorrhage alone. Furthermore, ibuprofen enhanced the release of TNF by SPL (+175%, P less than 0.05) and sM phi (+68%) compared to the vehicle group. Ibuprofen also decreased (P = 0.011) the susceptibility to sepsis following hemorrhage. These results indicate that PGs are involved in hemorrhage-induced suppression of cellular immunity and in the increased mortality of such animals following a septic challenge.

Animals↗
PubMed1992

Pituitary function before, during, and after chronic gonadotropin-releasing hormone agonist therapy.

OBJECTIVE: To examine possible adverse effects on pituitary function of long-term administration of gonadotropin-releasing hormone agonist (GnRH-a). DESIGN: Prospective analysis of blood sampling before, during, and after GnRH-a therapy. SETTING: Tertiary institutional outpatient care. PATIENTS: Twelve normally ovulatory women with a diagnosis of endometriosis. INTERVENTIONS: Six-month suppression with GnRH-a. MAIN OUTCOME MEASURES: Serum levels of follicle-stimulating hormone, luteinizing hormone, free thyroxin index, cortisol (F), growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH). RESULTS: Basal and stimulated values of gonadotropins, PRL, F, TSH, and GH were normal and unchanged by 6 months of GnRH-a after resumption of menses. CONCLUSIONS: Utilizing dynamic pituitary function tests, we were unable to demonstrate an adverse effect of long-term GnRH-a therapy on pituitary function.

Adult↗
PubMed1992

Diltiazem restores cardiac output and improves renal function after hemorrhagic shock and crystalloid resuscitation.

Although calcium antagonists produce salutary effects after shock and ischemia, it is unknown whether such agents restore the depressed cardiac output (CO) and renal function in a nonheparinized model of trauma-hemorrhage and resuscitation. To study this, rats underwent a midline laparotomy (i.e., trauma induced) and were bled to and maintained at a mean arterial pressure of 40 mmHg until 40% of the maximum bleedout was returned in the form of Ringer lactate (RL). They were then resuscitated with four times the volume of shed blood with RL over 60 min. Diltiazem (400 micrograms/kg body wt) or an equal volume of saline was infused intravenously over 95 min. This infusion was started during the last 15 min of resuscitation. CO was determined by indocyanine green dilution. Glomerular filtration rate (GFR) was assessed with [3H]inulin clearance, and cortical microcirculation was examined by laser Doppler flowmetry. Results indicate that crystalloid resuscitation alone transiently restored but did not maintain CO after hemorrhage. Diltiazem infusion in conjunction with crystalloid resuscitation, however, restored and maintained CO and cortical microcirculation. Although GFR decreased in both groups, the values in diltiazem-treated animals were significantly higher than those in the sham-operated animals. Furthermore, diltiazem markedly decreased tissue water content. Thus diltiazem appears to be a promising adjunct in the treatment of hemorrhagic shock even in the absence of blood resuscitation.

Animals↗
PubMed1992

Ovulation induction protocols.

Ovulation induction protocols for oocyte retrieval have evolved from clomiphene citrate/human menopausal gonadotropins (menotropins) to human menopausal gonadotropins alone and, finally, to a combination of human menopausal gonadotropins and an agonist of gonadotropin-releasing hormone (GnRH-a). The almost abandonment of clomiphene use is due to findings from studies that showed reduced implantation due to the antiestrogen effect of clomiphene. The use of GnRH-a was introduced to maintain low levels of luteinizing hormone late in follicular development to prevent premature ovulation or premature senescence of the oocyte. The GnRH-a increases oocyte yield in poor responders, decreases cycle cancellations, improves the rate of pregnancy, and allows some control over the timing of retrieval. Attempts to use the GnRH-a to stimulate follicle maturation in a "short protocol" have resulted in variable and sometimes poor results. Therefore, the long GnRH-a/human menopausal gonadotropin protocol is currently used for most patients to prepare for oocyte retrieval.

Clinical Protocols↗
PubMed1992

Energetics of defective macrophage antigen presentation after hemorrhage as determined by ultraresolution 31P nuclear magnetic resonance spectrometry: restoration with adenosine triphosphate-MgCl2.

BACKGROUND: The purpose of this study was to determine whether a decrease in macrophage energetics contributes to the profound immune dysfunction that occurs after hemorrhage and, if so, whether adenosine triphosphate (ATP)-MgCl2 treatment has any beneficial effects on the above parameters. METHODS: C3H/HeN mice were bled to a mean blood pressure of 35 mm Hg, maintained at that pressure for 60 minutes, resuscitated with their own shed blood and Ringer's lactate, and treated with ATP-MgCl2 (80 mumol/kg body weight) or saline solution (vehicle). Peritoneal macrophages were harvested 1 hour after resuscitation and ATP levels were determined by 31P nuclear magnetic resonance spectrometry. In addition, macrophage functions were determined by measuring antigen presentation capacity (AP), as well as interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor (TNF) synthesis. RESULTS: Hemorrhage caused a significant decrease in peritoneal macrophage AP function, as well as IL-1, IL-6, and TNF synthesis, by 52% +/- 14%, 91% +/- 12%, 78% +/- 8%, and 89% +/- 8%, respectively, which was correlated with a 78% +/- 6% decrease in macrophage ATP levels (p less than 0.05). Treatment with ATP-MgCl2 after hemorrhage restored macrophage ATP levels (p less than 0.05) and significantly increased (p less than 0.05) macrophage AP, IL-1, IL-6, and TNF release by 110% +/- 21%, 130% +/- 38%, 124% +/- 17%, and 66% +/- 24%, respectively. CONCLUSIONS: The decreased macrophage ATP levels may be the cause of defective macrophage AP and cytokine release after hemorrhage, and both macrophage ATP levels and macrophage immune functions can be restored with adjuvant ATP-MgCl2 treatment after hemorrhage.

Adenosine Triphosphate↗
PubMed1991

Diltiazem restores IL-2, IL-3, IL-6, and IFN-gamma synthesis and decreases host susceptibility to sepsis following hemorrhage.

Various beneficial effects of calcium channel blockers on cell and organ function following endotoxic shock, organ ischemia, and reperfusion have been reported; however, it is not known whether these agents have any salutary or deleterious effects on immune responses after low-flow conditions. Therefore, the aim of this study was to determine (a) the effect of hemorrhage on lymphocyte IL-2, IL-3, IL-6, and IFN-gamma synthesis, and (b) whether diltiazem has any salutary or adverse effects on these parameters when administered following hemorrhage and resuscitation. To study this, C3H/HeN mice were bled to a mean blood pressure of 35 mm Hg, maintained at that level for 60 min, and resuscitated with shed blood plus twice that volume of Ringer's lactate. Immediately following resuscitation mice received either diltiazem (2400, 800, or 400 micrograms/kg body wt), or an equivalent volume of saline. The mice were sacrificed 24 hr later, splenic lymphocytes were obtained, and their capacity to produce lymphokines was assessed. The results indicated that in the vehicle-treated animals, hemorrhage significantly decreased (P less than 0.05) IL-2, IL-3, IL-6, and IFN-gamma synthesis by 82 +/- 19%, 64 +/- 28%, 71 +/- 11%, and 86 +/- 14%, respectively. However, diltiazem (400 but not 2400 micrograms/kg) treatment after hemorrhage restored lymphocyte capacity to produce IL-2, IL-3, IL-6, and IFN-gamma (P less than 0.05). Additional groups of animals were subjected to sepsis by cecal ligation and puncture 3 days following hemorrhage.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Association between decreased splenic ATP levels and immunodepression: amelioration with ATP-MgCl2.

Although it is known that decreased ATP levels in liver and kidney contribute to organ dysfunction after shock, it remains unknown whether there is any association between decreased splenocyte ATP levels and splenic immune functions. Moreover, although studies have shown that ATP-MgCl2 treatment after shock improves hepatic and renal ATP levels and organ function, it remains unknown whether splenocyte ATP levels and immune functions are similarly affected by this agent. To study this, C3H/HeN mice were bled to a mean blood pressure of 35 mmHg, maintained at that pressure for 60 min, resuscitated with shed blood and Ringer lactate, and treated with ATP-MgCl2 (80 mumol/kg) or vehicle (saline). Splenocytes (SPL) were harvested at various intervals after hemorrhage, ATP levels were assessed by 31P nuclear magnetic resonance spectrometry, and functions were determined by measuring proliferative capacity and interleukin (IL)-2, and IL-3 synthesis. Hemorrhage depleted SPL ATP levels to 1.7 +/- 0.8% of control levels. However, there was a significant increase in ATP levels of ATP-MgCl2-treated mice (77 +/- 11%, P less than 0.05) compared with vehicle-treated animals (13 +/- 4.1%) at 1 h after resuscitation. SPL ATP levels returned to control by 2 h after resuscitation in the ATP-MgCl2 group, whereas ATP levels of the vehicle-treated mice remained significantly depressed (P less than 0.05) for up to 12 h after resuscitation. At 1 h after resuscitation, SPL proliferative capacity and IL-2 and IL-3 synthesis were all profoundly depressed in the vehicle-treated group (P less than 0.05 vs. control).(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1991

Lower pregnancy rate with premature luteinization during pituitary suppression with leuprolide acetate.

The relationship of the circulating level of progesterone (P) on the day of human chorionic gonadotropin (hCG) injection to occurrence of clinical pregnancy was examined in 133 leuprolide acetate human menopausal gonadotropin (hMG) in vitro fertilization cycles in women having at least three embryos transferred. Progesterone concentrations greater than 0.5 ng/mL were associated with a significantly lower rate of pregnancy (12/59, 20%) compared with less than 0.5 ng/mL (40/74, 54%, P less than 0.005). The higher P cycles were associated with greater patient age and hMG dose, although these relationships appeared to be indirect. Luteinizing hormone (LH) concentrations remained suppressed. Ovarian stimulation may cause excessive luteinization and an adverse cycle outcome even in the presence of low LH levels. Prospective use of P levels may be helpful to determine optimal hCG timing.

Adult↗
PubMed1990

Hemorrhage induces an increase in serum TNF which is not associated with elevated levels of endotoxin.

Although tumor necrosis factor (TNF) and interleukin 6 (IL 6) are purported to be important mediators of inflammatory responses following trauma, it is not known if the serum levels of these cytokines are altered by simple hemorrhage. The objective of this study therefore was to determine whether or not: 1) there is any elevation of TNF or IL 6, and 2) if endotoxin, an important upregulator of these cytokines, is also increased following hemorrhage. To study this, C3H/HeN mice were bled to, and maintained at a mean blood pressure of 35 mmHg for 60 min, and then resuscitated with their own shed blood and adequate fluid. Mice were sacrificed at 30 min into hemorrhage and at 2, 4 or 24 hr post-hemorrhage to obtain serum samples. IL 6 and TNF levels were measured using cytokine dependent cellular assays. Using a quantitative Limulus amebocyte lysate assay, endotoxin levels were determined. TNF levels were significantly elevated at 30 min into hemorrhage, remaining so at 2 hr after resuscitation, but absent by 4 hr. Although there was a trend toward elevated IL 6 levels at 2 hr following hemorrhage, which was sustained up to 24 hr, the values were not significantly different from sham controls. When compared to controls, no marked increase in endotoxin was seen at any time point during or following hemorrhage. These results indicate that hemorrhage, in the absence of significant tissue trauma, causes enhanced TNF release which is not the result of increased endotoxin.

Animals↗
PubMed1990

Leuprolide acetate lowers circulating bioactive luteinizing hormone and testosterone concentrations during ovarian stimulation for oocyte retrieval.

Levels of immunoreactive luteinizing hormone (LH), bioactive LH, and testosterone (T) were determined in 52 women receiving human menopausal gonadotropins (hMG). In 26 women receiving leuprolide acetate (LA) preceding hMG, there was a significant suppression of immunoreactive LH and bioactive LH. The characteristic increase in serum levels of bioactive LH and T were absent. Follicular fluid estradiol and T concentrations, and serum progesterone were not different. The lower circulating levels of T may reflect reduced LH-stimulated androgen accumulation in smaller nonaspirated follicles and may account for the enhanced follicle recruitment observed during LA. The lack of premature luteinization despite marked rises of bioactive LH in the absence of LA is consistent with normal events during the menstrual cycle and was due to the early termination of hMG stimulation.

Chorionic Gonadotropin↗
PubMed1990

Oocyte donation.

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Female↗
PubMed1990

Treatment of endometriosis with a long-acting gonadotropin-releasing hormone agonist plus medroxyprogesterone acetate.

Highly potent agonists of gonadotropin-releasing hormone (GnRH) have been shown to reduce pelvic pain due to endometriosis and the size and number of implants seen at laparoscopy. The accompanying symptoms and problems associated with the hypoestrogenism induced by the agonist have reduced its acceptability and raised questions about its safety. In an attempt to optimize this form of therapy, we treated eight women with endometriosis with daily subcutaneous injections of a potent agonist of GnRH plus a daily oral dose of 20-30 mg of medroxyprogesterone acetate for 24 weeks. Ovarian estrogen secretion was reduced to levels seen in castrated women throughout the course of treatment. Markers of hypoestrogenism, such as hot flashes and loss of calcium from bone, were diminished with this regimen compared with previous findings with GnRH agonist alone. Blinded evaluation of laparoscopic photographs failed to reveal improvement or suppression of active endometriosis. The results of this pilot study indicate that the addition of medroxyprogesterone acetate decreases the hypoestrogenic effects of GnRH agonist alone but fails to affect pain or endometriotic implants.

Adult↗
PubMed1990

Immunoprotective effect of a calcium channel blocker on macrophage antigen presentation function, major histocompatability class II antigen expression, and interleukin-1 synthesis after hemorrhage.

Hemorrhage induces a severe suppression of the immune system resulting in increased susceptibility to sepsis. Although studies indicate beneficial effects of calcium channel blockers on cell and organ functions after low-flow conditions, it remains unknown whether such agents have any effects on different immune responses after hemorrhage. To study this, C3H/HeN mice were bled to a mean blood pressure of 35 mm Hg and were maintained for 60 minutes, followed by resuscitation with their own shed blood and adequate fluid. The mice received either the water-soluble calcium channel blocker diltiazem (400 or 2400 micrograms/kg body weight) or saline solution (vehicle). Peritoneal macrophages were obtained by lavage 24 hours later. Antigen presentation was measured by coculturing peritoneal macrophages with the D10.G4.1 helper T-lymphocyte clone. Immune associated antigen (Ia) expression was determined by direct immunofluorescence. Interleukin (IL)-1, 6, and tumor necrosis factor-alpha (TNF) levels in peritoneal macrophage supernatants were measured by use of cytokine-specific cellular assays. Hemorrhage caused a significant decrease in peritoneal macrophage antigen presentation function, Ia expression, and IL-1 and IL-6 synthesis in the vehicle-treated group, whereas TNF levels were increased. However, both doses of diltiazem significantly improved peritoneal macrophage antigen presentation, Ia expression, and IL-1 synthesis. IL-6 synthesis was only increased with high doses of diltiazem, whereas both diltiazem doses decreased TNF production. These results indicate that the calcium channel blocker diltiazem can markedly improve macrophage functions after hemorrhage. The use of diltiazem might offer a new therapeutic modality in the treatment of immunosuppression and in decreasing the susceptibility to sepsis after hemorrhagic shock.

Animals↗