PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Lactation, Prolonged”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24Linked to original sources
PubMed2005

NO-mediated alterations in skeletal muscle nutritive blood flow and lactate metabolism in fibromyalgia.

UNLABELLED: The purpose of these investigations was to determine if differences exist in skeletal muscle nutritive blood flow and lactate metabolism in women with fibromyalgia (FM) compared to healthy women (HC); furthermore, to determine if differences in nitric oxide-mediated systems account for any detected alterations in blood flow and lactate metabolism and contribute to exertional fatigue in FM. FM (n = 8) and HC (n = 8) underwent a cycle ergometry test of aerobic capacity, a muscle biopsy for determination of nitric oxide synthase (eNOS, nNOS, iNOS) content, and microdialysis for investigation of muscle nutritive blood flow and lactate metabolism. During prolonged (3h) resting conditions, the ethanol outflow/inflow ratio (inversely related to blood flow) increased in FM over time compared to HC (P < 0.05). FM also exhibited a reduced nutritive blood flow response to aerobic exercise (P < 0.05). There was an increase in dialysate lactate in response to acetylcholine in FM, and to sodium nitroprusside in both groups, with a greater rise in dialysate lactate in FM (P < 0.05). The iNOS protein content was higher in FM and was negatively correlated with total exercise time (r(2) = 0.462, P < 0.05). IN CONCLUSION: (1) There is reduced nutritive flow response to aerobic exercise and reduced maximal exercise time in FM that might relate to higher iNOS protein content and contribute to exertional fatigue in FM; (2) The increased dialysate lactate in FM in response to stimulation of NOS or a nitric oxide donor suggest that FM may be more sensitive than HC to the suppressive effect of nitric oxide on oxidative phosphorylation.

Adaptation, Physiological↗
PubMed1994

The clinical usefulness of breast milk sodium in the assessment of lactogenesis.

OBJECTIVE: A study was undertaken to assess the value of breast milk sodium concentration (BM [Na+]) during early lactogenesis in predicting nursing outcome. METHODS: Samples of breast milk from 130 nursing mothers were obtained between the 3rd and 8th postpartum day for analysis of BM [Na+]. Approximately half the mothers were referred for nursing problems, although no problems were anticipated in the other primiparous mothers. A BM [Na+] of < or = 16 mmol/L was considered normal. For women with normal BM [Na+], follow-up was scheduled at 1 month, whereas those with high [Na+] were evaluated more frequently with repeated [Na+] determinations. RESULTS: Of the 65 women with normal BM [Na+] (excluding five mothers who had experienced breast surgery), 95.4% were exclusively and successfully breast-feeding at 1 month without intervention. Of 60 women with high BM [Na+], all of whom received intervention, 55% were ultimately successful. In general, those who failed tended to have higher initial [Na+] determinations; additionally, the longer the [Na+] remained elevated, the lower the success rate. Infant weight gain was greater if the initial BM [Na+] was normal. Infants of mothers with normal BM [Na+] gained an average of 994 g above birth weight by 1 month in contrast to the average weight gain of 818 g in infants of mothers with initially elevated [Na+]. CONCLUSION: This study suggests that a normal drop in [Na+] is highly predictive of successful lactation, although a prolonged elevation of [Na+] signifies impaired lactogenesis with a high risk of failure. The clinical usefulness and limitations of this determination are discussed.

Breast Feeding↗
PubMed1997

Simultaneous measurements of lactate and blood flow during hypoxia and recovery from hypoxia in a localized region in the brain of the anesthetized rabbit.

We observed simultaneous changes in lactate level and regional blood flow (rBF) in the brain of the anesthetized rabbit by using localized proton magnetic resonance spectroscopy (1H MRS) and laser Doppler flowmetry. The volume of interest of 0.5 ml for 1H MRS contained mostly thalamic nuclei. During hypoxia peak area for lactate increased up to 57% of that from N-Acetylaspartate. While the rBF increased during hypoxia up to 260% of the control, oxygen delivery (rBF x arterial oxygen content) decreased. In the normoxic recovery period following hypoxia, the rBF recovered slowly and a consequent overshoot of oxygen delivery was observed. The multiple and stepwise linear regression analyses revealed that the averaged decrease in oxygen delivery during hypoxia was the most significant independent variable for the increase in lactate during hypoxia (correlation coefficient; r2 = 0.68) and also that the increase in lactate during hypoxia was the most significant independent variable for the time for half-recovery of rBF (r2 = 0.75). These results suggest that the increase in lactate during hypoxia is due to the deficiency of oxygen delivery and that the increase in lactate during hypoxia prolongs the period of enhancement of rBF during recovery from hypoxia.

Anesthesia, General↗
PubMed1989

Long-term evaluation of a prolonged-release formulation of N-methionyl bovine somatotropin in lactating dairy cows.

Eighty Holstein cows (first, second, or third lactation) were used to evaluate the efficacy of a prolonged-release formulation for sometribove (n-methionyl bovine somatotropin). Cows were fed ad libitum a complete mixed diet and milked twice daily. Cows were allocated randomly by parity to two treatment groups receiving 500 mg sometribove in a prolonged release formulation or excipient at 14-d intervals starting at 60 +/- 3 d postpartum and continuing for 36 wk. Treatment with sometribove increased FCM yield to a similar extent (11.4%, +3.1 kg/d) in primiparous and multiparous animals. Milk content of lactose, fat, ash, and Ca was not affected, but protein and phosphorous were slightly greater (less than 5%) in milk from sometribove-treated cows. Within a 14-d injection interval, animals treated with sometribove displayed a cyclic pattern in milk yield, but a similar pattern was not evident in feed intake.

Animals↗
PubMed1991

Successful sustained lactation following postpartum tubal ligation.

This study was undertaken to see whether tubal ligation performed within days postpartum, and associated with a delay in the initiation of breastfeeding, exerts a disruptive influence on successfully establishing lactation among the rural population of northern Thailand. Lactational performance of 12 rural northern Thai mothers was not affected by the delay in reunion of mothers with their babies as a result of postpartum tubal sterilization procedure when compared with a group of 8 other healthy mothers and babies. The volume of breast milk transferred, frequency of breastfeeding and the total feeding time spent on the breast were similar on days 15, 45, 90, 180 and 360 postpartum. This finding suggests that the pattern of intense breastfeeding activity as practiced by this group of mothers has a stronger influence on prolonged and successful lactation than early contact in the immediate postpartum period.

Adult↗
PubMed2005

Early discharge from obstetrics-pediatrics at the Hospital de Valme, with domiciliary follow-up.

OBJECTIVES: This study was undertaken to evaluate the advantages and disadvantages of a program of early obstetric-pediatric discharge (24 hours postpartum) with domiciliary follow-up, compared with the traditional postpartum hospital stay (more than 48 hours), according to the criteria described by reviewers of the subject. STUDY DESIGN: A randomized controlled trial of early obstetric discharge for healthy mothers and term infants, with postpartum randomization, with no prenatal preparation and with observational and clinical follow-up was performed. The participants were mothers with healthy, term neonates (37-42 weeks) weighing more than 2500 g and produced via vaginal delivery and with a verified normal evolution before discharge. The sample consisted of 430 cases (213 cases with early discharge, and 217 control cases) in which the following variables were evaluated: existence of complications in the mother and/or child that required rehospitalization or a medical consultation, existence of maternal problems of fatigue or anxiety/depression after the birth, continuity of lactation and its problems, satisfaction of the mother and family, and relative costs. CONCLUSION: After demonstrating the homogeneity of the groups, no significant differences were found in the rates of maternal rehospitalization (1.9% in the early discharge group vs 2.3% in the control group, relative risk 0.81, 95% CI 0.21-3.03) or in the rates of rehospitalization of the neonates (1.4% in the early discharge group vs 2.3% in the control group, relative risk 0.16, 95% CI 0.15-2.56). No increases were observed in maternal or neonatal disease, puerperal fatigue, or maternal anxiety/depression. A prolongation of maternal lactation to 3 months was observed in the early discharge group (P=.016 <.05 Fisher exact test). When the cost of early discharge is compared with that of traditional discharge with a minimum of 48 hours hospital stay, we find a saving of 18% to 20%. The level of maternal satisfaction with early discharge is better than 90%.

Adult↗
PubMed2005

MR-spectroscopic imaging during visual stimulation in subgroups of migraine with aura.

Migraine pathophysiology possibly involves deficient mitochondrial energy reserve and diminished cortical habituation. Using functional magnetic resonance spectroscopic imaging (fMRSI), we studied cortical lactate changes during prolonged visual stimulation to search for different pathophysiological mechanisms in clinically distinct subgroups of migraine with aura. Eleven healthy volunteers (HV) and 10 migraine patients were investigated interictally: five with visual aura (MA) and five with visual symptoms and at least one of the following: paraesthesia, paresis or dysphasia (MAplus). Using MRSI (Philips, 1.5 T) (1)H-spectra were repeatedly obtained from a 25 mm-thick slice covering visual and non-visual cortex, with the first and fifth measurements in darkness and the second to fourth with 8-Hz checkerboard stimulation. In MAplus lactate increased only during stimulation, only in visual cortex; in MA resting lactate was high in visual cortex, without further increase during stimulation. This is compatible with an abnormal metabolic strain during stimulation in MAplus, possibly due to dishabituation, and a predominant mitochondrial dysfunction in MA.

Adult↗
PubMed2005

Fever control in septic shock: beneficial or harmful?

The beneficial effects of interventions to control fever in sepsis are controversial. We investigated whether the use of acetaminophen and external cooling is beneficial to control fever in septic shock. We studied 24 fasted, anesthetized, invasively monitored, mechanically ventilated female sheep (27.0 +/- 4.6 kg) that received 0.5 g/kg body weight of feces into the abdominal cavity to induce sepsis. Ringer's lactate (RL) was titrated to maintain pulmonary artery occlusion pressure (PAOP) at baseline levels throughout the experimental period. During the 2 h after the surgical operation, animals were placed in the hypothermia group if their temperature fell below 36.0 degrees C; the other animals were randomized to three groups: high fever (T > 39.0 degrees C), mild fever (37.5 degrees C < T < 38.5 degrees C), and normothermia (36.0 degrees C < T < 37.0 degrees C). The administration of 25 mg/kg acetaminophen every 4 to 6 h combined with external cooling (ice pad) was used to control core temperature in these three groups. The PaO2/FiO2 ratio was higher and blood lactate concentration was lower in the high fever than in the other groups (P < 0.01 and 0.05, respectively). Survival time was longer in the high fever group (25.2 +/- 3.0 h) than in the mild fever (17.7 +/- 3.5 h), normothermia (16.0 +/- 1.9 h), and hypothermia (18.5 +/- 2.5 h) groups (P < 0.05 for all). Plasma heat shock protein (HSP) 70 levels were higher in the two fever groups than in the other groups (P < 0.05). In this clinically relevant septic shock model, the febrile response thus resulted in better respiratory function, lower blood lactate concentration, and prolonged survival time. Antipyretic interventions including acetaminophen and external cooling were associated with lower circulating HSP70 levels. These data challenge the temperature control practices often used routinely in acutely ill patients.

Acetaminophen↗
PubMed2005

Extended use of a progesterone-releasing vaginal ring in nursing women: a phase II clinical trial.

AIM: This study evaluates the performance of extended use of a progesterone (P)-releasing vaginal ring (PVR) in nursing women. METHOD: An open-label, noncomparative study on the safety and contraceptive efficacy of PVR replaced every 4 months of use (instead of 3 months) in 192 PVR acceptors. PVR use was initiated at day 59+/-2 (mean+/-SD) postpartum and continued until weaning or completing the use of three PVRs. RESULTS: Plasma P levels attained with the ring decreased from 17+/-1 to 14+/-1 nmol/L (mean+/-SE) from the third to the fourth month of use. These levels are still over the critical level of 10 nmol/L required for contraceptive protection. One pregnancy occurred in the third month of use of the second ring in 1998 woman-months of exposure. Extended use of the ring did not appear to affect breast-feeding performance or the rate of infant growth, and lactational amenorrhea was prolonged. No differences in the characteristics of bleeding between the third and fourth month of ring use were observed. CONCLUSION: The results indicate that use of the PVR for 4 months represents a safe and effective contraceptive for nursing women.

Adolescent↗
PubMed1985

Role of the uterine cervix in inhibition of sexual behaviour in lactating rats.

Treatment of ovariectomized rats with progesterone-filled constant-release implants, which increased serum progesterone concentrations to 99.4 +/- 5.0 nmol/l, facilitated the induction of lordosis behaviour by subsequent treatment with oestradiol benzoate (OB, 10 micrograms). Concurrent treatment with the dopamine receptor antagonist domperidone (two daily injections of 2.5 mg/rat), which increased serum prolactin concentrations, did not inhibit the behavioural response of ovariectomized progesterone-treated rats to OB. If the treatment was combined with stimulation of the uterine cervix it inhibited lordosis to a level which was comparable with that of progesterone-domperidone-treated rats, which had been ovariectomized and from which the pups had been removed on the day of parturition. The cervical stimulation did not increase the amount of prolactin secreted by the pituitary gland in response to an injection of domperidone. The behavioural effect of cervical stimulation was blocked by injecting an anaesthetic paste (0.1 ml lidocain-prilocain) intravaginally against the cervix. The effect of cervical stimulation, or of parturition, lasted only for a few days and sexual behaviour was inhibited during a prolonged period of lactation. Sucking by the pups on the nipples of the mother may be required for preventing sexual behaviour during the entire period of lactation.

Anesthesia, Local↗
PubMed1980

Preliminary studies on the use of an oral progestogen to induce oestrus and ovulation in seasonally anoestrous Thoroughbred mares.

Daily oral administration of 30 mg allyl trenbolone (Regumate) for 10 to 15 days to 61 barren, maiden and lactating Thoroughbred mares which were exhibiting either deep anoestrus, shallow anoestrus, prolonged spring oestrus or lactation anoestrus, resulted in 54 mares (88 per cent) showing oestrous behaviour within 8 days, and 51 mares (84 per cent) ovulating within 18 days, after the last dose of compound. Response rate was lowest in mares in deep anoestrus. Of the 38 Regumate-treated mares which were covered during the induced oestrus, 21 (55 per cent) conceived. The practical value of this form of progesterone withdrawal therapy as a method for hastening the onset of the breeding season in Thoroughbred mares is discussed.

Anestrus↗
PubMed1991

Effect of endurance swimming on the lactate kinetics of rainbow trout.

The lactate turnover rate of rainbow trout (Oncorhynchus mykiss) was measured by bolus injection of [U-14C]lactate at rest and during prolonged swimming at 85% Ucrit to determine the importance of this metabolic fuel for endurance locomotion in fish, to assess whether lactate exchange between white and red muscle could be a possible mechanism for supplying oxidizable fuel to their lateral red muscle, and to compare the contribution of lactate to total energy provision between teleost and mammalian species. Turnover rate only increased from 4.41 +/- 0.33 to 9.71 +/- 1.69 mumol kg-1 min-1 between rest and prolonged swimming, and the contribution of lactate oxidation to total metabolism declined during exercise. Lactate exchange between white and red muscle is, therefore, not a significant mechanism to fuel the active lateral red musculature during prolonged swimming. The lactate turnover rate of teleosts is one or two orders of magnitude lower than in mammals of equivalent size, but lactate has the same importance as a fuel in both vertebrate groups. However, lactate turnover rate and oxidation rate do not scale with body mass in the same fashion as does metabolic rate. The slope of the mammalian relationship for whole-body lactate turnover and oxidation is much lower (0.58) than the slope of the classic relationship for metabolic rate (0.75), indicating that lactate is a much more important oxidative substrate for small than for large animals.

Animals↗
PubMed1989

Flurbiprofen in post-partum women: plasma and breast milk disposition.

The plasma and milk disposition of flurbiprofen (FB) was assessed in healthy women during the early post-partum period after multiple doses of FB. The results confirmed that a pragmatic study design is an attainable requirement for definitive statements about the excretion of FB in transitional milk. Nine doses of FB (50 mg per dose) were administered during three days. Paired milk and plasma samples were obtained during this period of dosing as well as after the last dose. The plasma data were used to derive an equation, which was then used to simulate cumulative plasma profiles for multiple doses given at unequal time intervals. The observed data corresponded to the simulated cumulative profiles of FB in plasma. The plasma elimination half-life of FB during early lactation was slightly prolonged (mean 4.8 hrs) as compared to reported values for normal adult men. The peak plasma concentrations of FB were comparable to those reported for healthy volunteers. In 10 of 12 women (3-5 days post-partum) the FB concentration in breast milk was less than 0.050 micrograms/ml. In two women the milk concentrations of FB were 0.06, 0.07 and 0.07 micrograms/ml as found in only three samples. We conclude that, on the basis of dose found in milk, FB is safe for women breast feeding their infants in the early post-partum period.

Adult↗
PubMedDate not supplied

Influence of a Biokinergia session on cardiorespiratory and metabolic adaptations of trained subjects.

BACKGROUND AND PURPOSE: Biokinergia (BK) is a massage aimed at improving "biological" potential. An initial pilot study demonstrated that a BK session could alter blood lactate concentration during prolonged exercise. OBJECTIVE: To confirm the effect of BK on performance and physiological adaptations during maximal aerobic muscular exercise. METHODS: Two groups of 10 subjects each performed a maximal progressive exercise on a cycle ergometer before and 10 days after a BK session (B group) or a feigned one (C group) in a simple-blinded manner. RESULTS: No modifications were noticed in the C group. After BK in the B group, maximum oxygen consumption was slightly increased (7%) and submaximal heart rate slightly lowered (4.7%) in 65% of the subjects; tidal volume was higher and breathing frequency was lower for 45% of the subjects. CONCLUSION AND DISCUSSION: The slight modifications induced by BK suggest that BK altered the sympathetic nervous system, but this needs confirmation.

Adaptation, Physiological↗
PubMed1992

Perinatal cocaine exposure and functional brainstem development in the rat.

Rat pups exposed to cocaine via maternal intromission throughout gestation and lactation displayed significantly prolonged auditory brainstem response component latencies and interwave intervals. Longitudinal analysis revealed that this effect was most pronounced on the 22nd postnatal day. Increasing the rate of stimulation further impaired neurosensory transmission in the caudal auditory pathway. These results indicate that both axonal and synaptic events may be affected to some degree and the timing (age) of optimum cocaine influence suggests that delayed myelination may be involved. The corresponding retardation in general development of the cocaine exposed pups further implicates maternal, fetal and postnatal utilization of nutritional resources as the basis for this outcome.

Analysis of Variance↗
PubMed1990

Unresectable hepatocellular carcinoma: a prospective controlled trial with tamoxifen.

The liver is an estrogen responsive organ. Clinically, estrogens may play a role in the induction of liver tumors and, experimentally, estrogens are involved in the control of hepatocyte proliferation. The results of a prospective controlled clinical trial using an anti-estrogen, tamoxifen, in patients with unresectable hepatocellular carcinoma (HCC) are presented below. Thirty-eight consecutive cirrhotics with HCC were allocated to either 30 mg/day tamoxifen or no treatment. The two groups of patients were matched for mean age, male/female ratio, Child-Pugh risk group, approximate tumor volume (US and/or CT scan) and etiology of the underlying cirrhosis. The drug appeared to have no side effects. Survival was significantly prolonged in tamoxifen-treated patients with 22% (vs. 5%) survival at 12 months. No differences were observed between males and females or alcoholic and non-alcoholic cirrhosis. In 53% of tamoxifen-treated patients the levels of alpha-fetoprotein dropped and, in this subgroup, survival was further prolonged. Tumor volume, lactate dehydrogenase (LDH) and alkaline phosphatase slowly increased, suggesting a slower, but continuous, progression of the disease. In conclusion, anti-estrogen treatment appears effective in the palliation of unresectable or otherwise untreatable HCC. A reduction in alpha-fetoprotein levels appears to be a favorable prognostic index.

Aged↗
PubMedDate not supplied

Hormonal effects on hamster lacrimal gland female-specific major 20 kDa secretory protein and its immunological similarity with submandibular gland major male-specific proteins.

Hormonal regulation of a major 20 kDa protein of hamster exorbital lacrimal gland (LG) was studied by SDS-PAGE profile analysis and the purified protein's antisera was used to screen tissues of hamster and other species for crossreacting proteins. This protein was seen in female LG but not in males and late-pregnant or hCG-treated females. Low estrogen state in females after gonadectomy, prolonged light-deprivation, prolonged starvation or lactation increased its level several folds to approximately 20% of LG soluble proteins and similar levels were induced in males after gonadectomy (low androgen state). However, light-deprivation or melatonin treatment-induced low androgen state in males had no effect. In gonadectomized hamsters, this LG protein was obliterated on treatment with androgens, estrogens or thyroid hormones. Only estrogen inhibition of LG 20 kDa was prevented by simultaneous tamoxifen administration. Simultaneous treatment of gonadectomized hamsters with gonadotrophins and estrogen/androgen did not prevent the LG 20 kDa protein's inhibition. Relative potencies of estrogens (3.6 microg daily dose) were: estradiol-17beta approximately diethylstilbestrol > estrone > estradiol-17alpha, while estriol and chlorotrianisene had no effect. Dexamethasone, progesterone, prolactin, hypothyroid state or adrenalectomy had no effect on LG 20 kDa expression. Western blot studies confirmed the marked repression of LG 20 kDa by estrogen androgen and thyroid hormone and detected the protein in tears of females and gonadectomized hamsters but not in males. Interestingly, among other tissues tested, crossreaction was only seen with the estrogen-repressed 24 and 20.5 kDa major male-specific secretory proteins of hamster submandibular glands (SMG) which were previously reported by us. This strongly indicated that the LG and SMG proteins are products of the same or closely related genes. A possible role for these hamster sex-specific LG and SMG major secretory proteins in olfactory communication is suggested.

Androgens↗