[Metamizol versus propacetamol: comparative study of the hemodynamic and antipyretic effects in critically ill patients]

OBJECTIVE

To compare the antipyretic and hemodynamic effects of metamizol and propacetamol in critically ill patients with fever.

PATIENTS AND METHODS

A prospective randomized trial enrolling 60 patients admitted to our postoperative intensive care unit with fever > 38 degrees C. Patients were assigned to group M to receive intravenous doses of 2 g of metamizol or group P to receive 2 g of propacetamol. Measures were central temperature (Ta), systolic (SBP), diastolic (DBP) and mean (MBP) blood pressures, mean pulmonary artery pressure, central venous pressure, pulmonary capillary pressure, pulmonary and systemic vascular resistance index, and mixed venous saturation. All measures were taken at four times: baseline and 30, 60 and 120 minutes after infusion of the medication. Patients whose SBP fell below 90 mm Hg were withdrawn from the study.

RESULTS

Patient characteristics and baseline hemodynamics and Ta were similar in the two groups. We observed a significant decrease in temperature in both groups, the maximum decrease occurring 120 minutes after administration of the antipyretic (0.5 degree C and 0.6 degree in the metamizol and propacetamol groups, respectively). SBP, DBP, MBP, and the vascular resistance index decreased from baseline values in both groups 30, 60 and 120 minutes after dosing. Thirteen percent of the patients in group M and 6.67% in group P were withdrawn from the study because of hypotension. We observed no statistically significant differences between the groups in Ta or hemodynamic variables at any of the four moments of measurement.

CONCLUSION

Both metamizol and propacetamol are effective antipyretics at the doses tested. However, both have adverse hemodynamic side effects that may be poorly tolerated by critically patients.

Greater genetic variability in Argentine Creole than in Thoroughbred horses based on serum protein polymorphisms

Genetic polymorphism was analyzed for five blood proteins: albumin - Al, esterase - Es, alpha(1)B-glycoprotein - Xk, transferrin - Tf and hemoglobin - Hb in 200 Thoroughbred (TB) and 124 Argentine Creole (AC) horses. Of the five systems examined, Tf and Hb were not in Hardy-Weinberg equilibrium in either breed and Es was not in equilibrium in the Creole breed. Genetic variability, estimated as average heterozygosity, was higher in AC (H = 0.585 +/- 0.131) than in TB (H = 0.353 +/- 0.065). The genetic differentiation between these two populations (F(ST)) was 0.109. Thus, of the total genetic differences between breeds, the proportion of genetic variation attributable to breed differences was about 10%; the remaining 90% was due to individual variation within breeds. The high degree of genetic variability seen in Argentine Creole horses could be a consequence of natural selection. Selection of TB through the centuries has most likely modified the gene pool of the ancestral population, with a consequent reduction in variability at certain loci. Probably, different mechanisms exist for maintaining polymorphism at these loci in TB and in AC horses. Heterozygosity may have played a fundamental role in adaptation.

Contraceptive efficacy and clinical performance of Nestorone implants in postpartum women

The objective of this study was to evaluate the contraceptive efficacy and clinical performance of a Nestorone subdermal implant (NES) in the postpartum period. NES (n = 100) and Copper T intrauterine device (T-Cu; n = 100) acceptors initiated contraception at 8 weeks postpartum and were followed at monthly intervals during the first year and at 3-month intervals thereafter. Pregnancy rates, breastfeeding performance, infant growth, bleeding pattern, and side effects were assessed. Blood and milk NES concentration were measured. No pregnancy occurred in 2195 and 2145 woman-months of NES implant and T-Cu use, respectively. No effect of NES on lactation and infant growth and no serious adverse events were observed. Lactational amenorrhea was significantly longer in NES users (353 +/- 20 days) than in T-Cu users (201 +/- 11 days). More NES users (55.8%) experienced prolonged bleedings than did T-Cu users (36.2%). Concentrations of NES in breast milk ranged between 54-135 pmol/liter. The Nestorone implant is a highly effective contraceptive, safe for breastfed infants because the steroid is inactive by the oral route.

Genetic variation of the second exon of ELA-DRB genes in Argentine Creole horses

Genetic variation in the equine leucocyte antigen-DRB (ELA-DRB) second exon was investigated using polymerase chain reaction (PCR) amplification, restriction fragment length polymorphism (RFLP) of PCR products (PCR-RFLP) and deoxyribonucleic acid (DNA) sequencing. Eight distinct PCR-RFLP patterns could be identified in the studied Argentine Creole (AC) horses. The number of observed patterns per individual ranged from four to six, thus confirming the presence of multiple DRB copies in AC horses. Three PCR-RFLP alleles and three new sequences were identified. The estimated rates of synonymous and non-synonymous substitutions among ELA-DRB exon 2 sequences were higher within the antigen recognition site (ABS) than on the non-ABS. Phylogenetic analysis showed that the nucleotide sequences clustered in two main groups, while some sequences were not included in either group. Finally, the identification of the number of alleles per animal, the phylogenetic and segregation analyses allowed us to explain the number of ELA-DRB loci. However, it was not possible to identify specific alleles with specific loci.

[Improved oxygenation with nitric oxide treatment for hepatopulmonary syndrome after a liver transplant]

A 37-year-old man with cirrhosis of the liver hospitalized for orthotopic liver transplant (OLT) was found to have hepatopulmonary syndrome (HPS) during routine presurgical assessment. No problems with oxygenation developed during surgery. In the early recovery period, however, hypoxemia was observed to be uncorrected in spite of gradual normalization of liver function tests. OLT sometimes corrects HPS and, therefore, hypoxemia. However, significant decreases in oxygenation during recovery have been reported to affect patient morbidity and mortality. We therefore started low-dose nitric oxide (NO) inhalation once other possible causes of hypoxemia had been ruled out. Oxygenation improved, allowing tubes to be removed. Seven months after OLT, home oxygen therapy was still required to treat basal hypoxemia. HPS persisted, as confirmed by echocardiogram. Inhaled NO contributed to maintenance of adequate oxygenation during the early postoperative period, as essential for long-term survival in patients with HPS who undergo OLT.

Ecological approaches to rural development projects

Most rural development projects include ecological considerations, and most conservation projects include some reference to sustainable development. However, conservation projects frequently fail because they do not incorporate local communities' perceptions and needs. Many development projects are also unsuccessful because they are not based on adequate ecological assessment. We focus here on the most important ecological issues to be addressed in order to place development projects in an ecosystem context. Such projects should incorporate updated and precise ecological concepts and methods. Some key ecological issues in development projects are the relationships between ecosystem functions, services, and sustainability, the concept of loose connectivity, the distinct and complementary concepts of ecosystem resistance and resilience, and the links between biodiversity and ecosystem functioning. We claim that an ecologically sound development project maximizes the preservation and improvement of ecosystem services, especially for local communities. We pose a series of questions aimed at placing rural development projects in an ecosystem context and suggest ways of organizing this information.

High intensity light increases olfactory bulb melatonin in Venezuelan equine encephalitis virus infection

In mice infected with the Venezuelan equine encephalomyelitis (VEE) virus and exposed to high intensity light (2500 lux) with a 12 h light: 12 h dark photoperiod, a significant increase in the levels of melatonin in the olfactory bulb was observed. The significance of these findings deserves further studies to understand the mechanisms involved in this effect since the olfactory bulbs have been proposed as first portal for VEE virus entry into the CNS. The increase in melatonin content could represent one of the mechanisms of defense against the viral attack.

Vaginal rings for contraception in lactating women

Contraceptive methods for breastfeeding women should be safe for the mother and infant and should not interfere with lactation. Progestin-only methods meet these conditions and can be used from the sixth week postpartum. Because all progestins are excreted in milk, those that are insufficiently active by the oral route are preferable to avoid any possible effect on the baby. These steroids, however, must be administered to the mother by a non-oral route. Initially, progesterone was administered subdermally to test this concept. Subsequently, a progesterone vaginal ring was developed to be used continuously for 3 to 4 months and replaced with a new device, as needed, until weaning. Clinical trials have shown a high contraceptive efficacy (over 98.5%) and safety. The gross continuation rate of this method is approximately 40% at 12 months of use, with use-related problems being the main reason for discontinuation (26.8%). Currently, a Nestorone vaginal ring is under development, delivering 50 microg of Nestorone per day. It may be used continuously for up to one year, even if weaning occurs earlier. Both of these progestin-only rings prolong lactational amenorrhea to 10 to 12 months, which represents a health benefit and convenience for many women. The registration of the progesterone vaginal ring, developed as a contraceptive method to be used exclusively during lactation, has been approved in Chile and Perú. The fact that it is a user-controlled long-term contraceptive that delivers a natural hormone makes it an attractive option for many women.

Voice restoration after total laryngectomy with tracheoesophageal puncture and voice prosthesis

Removal of the voice box or larynx is the usual treatment for advanced cancer of the larynx. Tracheoesophageal puncture (TEP) has become an accepted method for voice restoration following total laryngectomy. Eleven patients under went total laryngectomy with TEP at San Pablo Hospital Medical Center between March 1989 and October 1995. Seven patients were available for voice analysis. Eighty six percent of the patient was able to talk. This is the first report of TEP being perform in Puerto Rico and with a complete Hispanic population of patients. Results compare favorably with those reported in the medical literature.

The effect of pH on the kinetics of intra- and extracellular uptake of Al in Fontinalis antipyretica: changes in the cellular contents of K, Mg, and Ca

The effect of acidity on the accumulation of Al in the aquatic bryophyte Fontinalis antipyretica was studied. The main interest of this study was in characterizing the relationship between the two parameters, as Al is typically mobilized in acidic environments, where it becomes extremely toxic. With this aim, a series of laboratory experiments were carried out where samples of F. antipyretica were held in tanks of water with different concentrations of Al (0.1-3 mg L(-1)) and levels of acidity (pH 3-5. 8). The incubation time varied between 1 and 24 h. In general, the greatest accumulations of both intra- and extracellular Al were found at a pH of 4.4. With the results obtained, the kinetics of both intra- and extracellular Al uptake was characterized, and models constructed for different combinations of Al and acidity. The study was completed by examining the relationship between the pH of the holding water and bioaccumulation of Al and the variation in concentration of cations essential to plant life, which are also indicators of changes in cellular physiology (K, Mg, Ca). In general, losses of these elements were found at intra- and extracellular locations, especially at high pH.

Consequences of changing biodiversity

Human alteration of the global environment has triggered the sixth major extinction event in the history of life and caused widespread changes in the global distribution of organisms. These changes in biodiversity alter ecosystem processes and change the resilience of ecosystems to environmental change. This has profound consequences for services that humans derive from ecosystems. The large ecological and societal consequences of changing biodiversity should be minimized to preserve options for future solutions to global environmental problems.

Effect of trehalose and sucrose on the hydration and dipole potential of lipid bilayers

The water activity in dimyristoylphosphatidylcholine (DMPC) decreases by 60% when the lipid is dehydrated in the presence of trehalose concentrations higher than 0.02 M. In contrast, sucrose in concentrations 10 times higher produced only a 20% decrease in the water activity in the sample. Titrations of a DMPC solution in chloroform yielded 14 water molecules per lipid when pure water was added and seven water molecules per lipid when the titration was done with 0.025 M trehalose. The same concentrations of sucrose produced a turbid solution, which made it impossible to quantify the number of water molecules per lipid. Lipid monolayers spread on an air/water interface showed a decrease from 480 mV in pure water to 425 mV in 0.1 M trehalose. However, the same concentrations of sucrose produced an increase of less than 100 mV. Results obtained with Fourier transform infrared spectroscopy (FTIR) under the same conditions denoted that trehalose binds to the carbonyl groups, while sucrose showed no specific binding. It is concluded that per lipid molecule, 11 of 14 water molecules can be replaced by three trehalose molecules. About four are displaced by changes in the water activity of the bulk solution, and seven by specific interactions with the phospholipids. In this last case, at least two of them are linked to the carbonyls, and this appears to be the cause of the decrease in the dipole potential of the membrane. In contrast, four sucrose molecules displace only three water molecules per lipid, with no effect on the dipole potential or the carbonyl groups.

Preparation and characterization of novel trans-[PtCl(2)(amine)(isopropylamine)] compounds: cytotoxic activity and apoptosis induction in ras-transformed cells

The synthesis and chemical characterization of three new transplatinum complexes of structural formula trans-[PtCl(2)(amine)(isopropylamine)] (amine = n,n-dimethylamine, propylamine, and butylamine), 1-3, are described. Cytotoxicity tests in tumor cell lines sensitive to cis-DDP (Jurkat, Hela, and Vero) and also in tumor cell lines overexpressing ras oncogenes and resistant to cis-DDP (HL-60 and Pam 212-ras) show that complexes 1 and 3 have higher cytotoxic activity than cisplatin. Moreover, these two trans-Pt(II) complexes kill Pam 212-ras cells through apoptosis induction. These results suggest that trans-PtCl(2) complexes with asymmetric aliphatic amines may be considered a new class of biologically active trans-platinum drugs.

Norplant((R)) implants and progesterone vaginal rings do not affect maternal bone turnover and density during lactation and after weaning

Bone density and turnover was assessed in a longitudinal study of healthy lactating women who initiated use of Norplant((R)) implants (NOR, n = 29), progesterone vaginal rings (PVR, n = 28) or Copper T 380A intrauterine devices (T-Cu, n = 51, control group) around day 60 postpartum. Bone density, serum calcium, phosphorus, alkaline phosphatases, parathyroid hormone (PTH), follicle stimulating hormone (FSH), oestradiol and prolactin, and urinary hydroxyproline and creatinine were measured at postpartum months 1 (PM1), and 12 (PM12) and 6 or 12 months after weaning; at month 6 postpartum (PM6) serum and urine tests alone were performed. Baseline characteristics and lactation performance were similar between groups. Biochemical markers of bone turnover were higher at PM1, PM6 and PM12 than after weaning, with no differences between groups. Bone density in the lumbar spine (L2-L4) and femoral neck at PM1 and PM12 ( approximately 1.11 g/cm(2)) was similar in three groups. Lumbar spine values were found to be lower in lactating women than those present in non-lactating women, but increased after weaning to similar values. The two progestin-only contraceptives studied appear to have no deleterious effect upon bone density and metabolism in healthy lactating women.

Preregistration study on the safety and contraceptive efficacy of a progesterone-releasing vaginal ring in Chilean nursing women

The contraceptive efficacy and safety of a progesterone-releasing vaginal ring (PVR) manufactured in Chile were compared to that of the Copper T 380A IUD (T-Cu) in nursing women enrolled at three Chilean clinics. A total of 285 volunteers chose to use the PVR and 262 the T-Cu. Plasma progesterone levels attained with the ring decreased from 25 to 14 nmol/L from month 1 to month 3 of use. Ring replacement was scheduled every 3 months. Volunteers continued in the study until weaning or completing the continuous use of four PVRs. No pregnancies occurred in 2320 and 2183 woman-months of exposure with the PVR and the T-Cu, respectively. Lower continuation rates in the first 6 months because of problems with use and a longer lactational amenorrhea were observed in the PVR than in the T-Cu group. Breast-feeding performance and infant growth were similar in both groups. These results confirm the high efficacy and safety of the PVR for nursing women and have led to the registration of the PVR by Chilean health authorities.

Beneficial effects of diphenhydramine in dystonia

The objective of this paper was to evaluate the efficacy of diphenhydramine hydrochloride (DPH) in dystonic patients. In 1995, Truong et al reported encouraging results in five patients with idiopathic torsion dystonia (ITD) treated with DPH, an H1 antagonist with sedative and anticholinergic properties. Five patients with generalized ITD, one with secondary generalized dystonia and one with idiopathic segmental dystonia were included in the prospective study. Initially the response to intravenous administration of DPH versus placebo in two sessions a week apart was evaluated. Two weeks later all patients started oral DPH in increasing doses (range 100-300 mg, mean 164 mg). The degree of dystonia was determined by a modified University of Columbia Scale evaluating the baseline score, after placebo and DPH I.V. administration then at one and six months after starting oral treatment. The results were analyzed by Friedman's test for repeated measurements. On comparing scores for baseline severity, I.V. placebo and I.V. DPH presented a highly significant correlation (12.09; p = 0.00) as well as comparing baseline score with oral DPH at one and 6 months, treatment (12.78; p = 0.00). Functional score results were 9.5 p = 0.01 and 8.4 p = 0.02 at one and 6 months respectively. The most common side effects were somnolence and dizziness. It can be concluded that DPH proved effective in our patients with mild to moderate adverse effects not requiring drug withdrawal in any case. However, I.V. challenge was unable to predict the long-term response to oral medication perhaps due to the limited number of cases.

Bioactivity of prolactin isoforms: lactation and recovery of menses in nursing women

To assess whether plasma prolactin (PRL) characteristics relate to lactogenesis and absence or presence of menstrual cycles, we measured bioactive PRL (BIO-PRL) using the Nb2 assay, immunoreactive PRL (IR-PRL) by radio-immunoassay, calculated equations describing the BIO-PRL-IR-PRL relationship and separated charged PRL isoforms (by chromatofocusing) in five amenorrhoeic and five cycling nursing women at 6 months postpartum and in 10 cycling non-nursing women. Plasma samples were drawn before and 30 min after a suckling episode at 0800, 1600 and 2400 h in nursing women and at the same hours in non-nursing women. BIO-PRL and IR-PRL concentrations were highest in amenorrhoeic nursing women, intermediate in cycling nursing women and lowest in cycling non-nursing women. The BIO-PRL-IR-PRL relationship shows that a given amount of IR-PRL corresponds to equivalent amounts of BIO-PRL in cycling nursing and cycling non-nursing women, and to a larger extent in amenorrhoeic nursing women. IR-PRL was present in plasma as several charge isoforms. Bioactive isoforms eluting at pH 6.0-5.1 were found in amenorrhoeic and cycling nursing women, reaching similar concentrations after suckling. Bioactive isoforms eluting at pH 7.0-6.1 were found only in amenorrhoeic nursing women. We speculate that isoforms eluting at pH 6.0-5.1 may play a role in lactation and isoforms eluting at pH 7.0-6.1, in lactational amenorrhoea.

Contraceptive technology and family planning services

A large variety of modern contraceptives is now available, including several means to administer hormonal contraception, highly effective long-term methods and simple sterilization techniques. Methods under research include immuno-contraceptives for women and men, hormonal methods for men, new approaches to female hormonal contraception and improved barrier methods. Modern contraceptives are effective and safe for most women, and some methods have beneficial health effects other than prevention of pregnancy. However, underlying health conditions may decrease the safety of a given method. The appropriate use of the technology available requires screening for biomedical conditions and counseling that enables the selection of methods according to the life style of women and couples. Contraceptive methods have had a considerable positive impact on maternal and infant health and on population growth, but unwanted pregnancies and unsafe abortion still occur in large numbers. This shows the need to improve access to and quality of family planning services including the availability of contraceptives, sensitive providers trained in technical matters and communication skills, and communication between the community, the providers and the managers.

Inertia and Resilience in the Responses of the Aquatic Bryophyte Fontinalis antipyretica Hedw. to Thermal Stress

The physiological responses of the aquatic bryophyte Fontinalis antipyretica Hedw. to high temperatures, ranging from 16 degreesC (control) to 34 degreesC, were investigated experimentally. Plant samples were maintained at the temperature under study for up to 25 days with regular determination of physiological variables (pigment ratio and photosynthetic and respiratory rates). Physiological responses to temperature did not differ significantly between mosses collected from a normal river site and from a river site with abnormally high temperature due to input from a hot spring. Simple curve-fitting procedures and summary statistics analogous to those used in toxicological research were employed to compare responses as revealed by the different physiological variables. In a second series of experiments, the capacity of F. antipyretica to recover from high-temperature stress was investigated by maintaining samples at 30 degreesC for 2, 4, or 10 days, then transferring the samples to normal conditions (16 degreesC) for 40 days. Physiological variables were again monitored at regular intervals throughout both phases of the experiment. In general, good recovery was observed even after exposure to high temperatures for 10 days. The results of these assays allow quantification of the relationship between a pigment ratio and net photosynthesis rate.

Fertility regulation in nursing women. IX. Contraceptive performance, duration of lactation, infant growth, and bleeding patterns during use of progesterone vaginal rings, progestin-only pills, Norplant implants, and Copper T 380-A intrauterine devices

This study evaluated the performance of progesterone vaginal rings (n = 187), progestin-only pills (n = 117), Norplant implants (n = 120), and Copper T 380-A intrauterine devices (n = 122) in lactating women. Contraceptive efficacy, bleeding pattern, and influence of the method upon breastfeeding duration and infant growth were compared with those of untreated women (n = 236) who relied on lactational infertility. Participants were healthy, 18 to 38 years, had had a normal delivery, and were intending to breastfeed for as long as possible. Contraceptives were initiated at day 57 +/- 3 postpartum. Results are reported for the first year of use. All methods were highly effective, with pregnancy rates below 1%. None affected breastfeeding performance or the rate of infant growth. Users of the progestin-only methods experienced a period of lactational amenorrhea 4 to 5 months longer than did users of Copper T or untreated women. More than half of the women in each contraceptive group reported a bleeding in the first month after treatment initiation, which was not considered in the calculation of the duration of amenorrhea. Prolonged or frequent bleedings were infrequent. The proportion of bleedings lasting more than 10 days ranged from 0 in the progestin-only pills group to 7% in the Norplant implants group. The four methods, initiated around the eighth postpartum week, provided effective contraception with no negative effects upon lactation or infant growth and without the bleeding problems associated with their use in nonlactating women.

Post-suckling prolactin:oestradiol ratio--a potential index to predict the duration of lactational amenorrhoea in women

To assess whether the duration of lactational amenorrhoea can be predicted in individual women, we studied the pre- and post-suckling concentrations of immune prolactin (IR-PRL) and of bioactive prolactin (BIO-PRL) and basal concentrations of oestradiol in ten amenorrhoeic fully nursing women at 3 months post-partum. The women were of similar age, weight and had infants of similar growth rate. Five of these women were to experience long amenorrhoea (>180 days) and the others short amenorrhoea (<180 days). Blood samples were drawn 30 min after a suckling episode initiated at 0800 h, 1600 h and 2400 h. BIO-PRL distinguished between groups of women at 0030 h but not at other times, while there was considerable overlap between values for IR-PRL and oestradiol at all times studied. At 1630 h, the ratios post-suckling BIO-PRL: oestradiol and post-suckling IR-PRL:oestradiol were above 2000 in the women that were to experience long amenorrhoea and below this threshold in the other women. The ratio post-suckling BIO-PRL:oestradiol provided more information since the difference between the lowest ratio in the long amenorrhoea and the highest ratio in the short was 699, while it was 520 for the IR-PRL:oestradiol ratio. The determination of these ratios may help to predict the duration of lactational amenorrhoea in individual fully nursing women.

Contraceptives for lactating women: a comparative trial of a progesterone-releasing vaginal ring and the copper T 380A IUD

From approximately one week before normal ovulation resumes, lactating women require protection against pregnancy by a contraceptive that is safe for both infant and mother in a multicenter one-year study, the natural hormone, progesterone, delivered vaginally by a sequence of four contraceptive rings designed for continuous use, was evaluated as a contraceptive for nursing mothers in comparison with the Copper T 380A IUD. Individual rings release in effective average dose of 10 mg day for a 3 month period. Evaluation included measures of lactational performance as well as of contraceptive efficacy and safety to mother and child. Nine participating clinics enrolled 802 ring users and 734 IUD acceptors between postpartum days 29 and 63. Life table analyses were performed with parallel decrements for ring and IUD subjects. Continuation in the study and analysis required that subjects not stop breastfeeding. The ring, with a one-year pregnancy rate of 1.5 per 100, did not differ significantly from the IUD with respect to contraceptive effectiveness (p > 0.05). More than half of the ring subjects were continuing at 6 months post admission and a quarter (23.5 per hundred) were still using the ring and breastfeeding one year after admission. Women with the IUD, however, had higher continuation rates (p < 0.001) at both time points. The largest single decrement for each method was that for weaning. Ring users had more complaints of vaginal problems but had fewer vaginal disorders on examination. At 12 months postpartum, 46 per 100 continuing ring users remained in amenorrhea. Lactation performance and the health and weight gain of the infants were similar among users of either regimen.

[Immunologic characteristics of undernutrition. I. The undernourished patient in nutritional recovery]

Malnutrition in children is a well known critical factor that determines immunocompetence changes with altered immune response and higher risk to many diseases, especially in developing countries. Moreover, it is related to increased morbi-mortality rates mainly due to infections. For those reasons, 12 undernourished children, age 5 to 24 months were studied along 8 weeks at the Nutritional Recovery Center of Chiquinquira Hospital in Maracaibo, Venezuela. There were 5 cases of kwashiorkor, 5 marasmatics, 1 mixed marasmus/kwashiorkor and 1 case with moderate malnutrition. After a control blood sample was taken and cutaneous tests were done, a nutritional recovery program was began. At regular time intervals and at the end of the study, tests were done again by measuring seric immunoglobulins (IgG, IgA, IgM), secretory IgA (IgAs), C3 and C4 complement, lymphocytic sub-populations, and auto antibodies; cutaneous hipersensitivity tests were also done. As a control group, 10 apparently healthy children of matching age and sex were also studied with the same parameters. Results show that basal seric Igs did not differ significantly from the control group and did not change along the recovery program period, but there was a significant decrease in IgAs at all times of the study. C4 did not change and C3 was lower than control (p < 0.05) but returned to normal value at the end of the recovery period. CD3 and CD4 lymphocytes showed the same pattern. Only two patients showed positive skin tests and auto antibodies were not detected. It is concluded that there is indeed an altered immune competence with low levels of C3, IgAs, and CD3-CD4 lymphocytes that is reversible after nutritional recovery.

Value of the peak expiratory flow in bronchodynamic tests

OBJECTIVE

To determine the accuracy of the peak expiratory flow (PEF) as an alternative parameter to the forced expiratory volume at first second (FEV1) in the bronchodynamic tests.

METHODOLOGY

We studied 84 patients, 53 males and 31 females, with average age 46 +/- 13 years, as clinic suspects of bronchial asthma. PEF was determined with a "mini-Wright peak flow meter" and a spirometry was obtained. Based on the results, 44 subjects were classified under group 1 (FEV1/FVC < 70% and FEV1 < 80% of theoretic value) and subjected to a bronchodilator test. While in group 2 subjects (normal spirometry), a methacholine challenge was performed. During each procedure, PEF readings were obtained before FEV1 determination. The usefulness of the PEF for the diagnosis of reversibility or bronchial obstruction with respect to the FEV1 was assessed in both groups.

RESULTS

In the bronchodilator tests, a cut-off point was found for the increase in the PEF > 18%, which showed a sensitivity of 85%, specificity of 79%, positive predictive value of 77% and negative predictive value of 86%, with respect to an increase in the FEV1 > 15%. In the methacholine challenge, a decrease in the PEF > 12% only achieved a sensitivity of 74% and specificity of 71%.

CONCLUSION

Peak expiratory flow may be an useful parameter in bronchodilator tests. However, it should not be used in methacholine challenge.

Bone turnover and density in healthy women during breastfeeding and after weaning

To investigate the changes in maternal bone density and turnover associated with lactation we ran a longitudinal study in fully breastfeeding women (age 26.3 +/- 4.1 years, mean +/- SD) at the first (stage I, n = 30) and sixth (stage II, n = 25) months postpartum and 6 months after weaning (stage III, n = 20), and in a contemporary control group of non-nursing women. At each time point bone density, serum calcium, phosphorus, alkaline phosphatases, parathyroid hormone (PTH), osteocalcin, follicle stimulating hormone (FSH), estradiol (E2), prolactin (PRL) urinary hydroxyproline and creatinine (OH-P/Cr) were measured in both groups. The daily calcium intake of nursing women (1479 +/- 590 mg/day at stage I) was higher than in non-nursing women (536 +/- 231 mg/day at stage I). Biochemical markers of bone turnover were higher (p < 0.05) in nursing than in non-nursing women at stages I and II, while in stage III only OH-P/Cr was elevated. The lumbar spine (L2-4) bone mineral density was similar in the two groups at the beginning of the study (1.148 +/- 0.111 g/cm2 in nursing women vs 1.211 +/- 0.102 g/cm2 in non-nursing women; p = 0.06), but it was lower in nursing women at stage II (1.144 +/- 0.110 g/cm2 vs 1.216 +/- 0.095 g/cm2 respectively; p < 0.05). Right femoral neck bone density decreased by 3% between stages I and II in nursing women but did not differ from values in non-nursing women (0.947 +/- 0.110 vs 0.973 +/- 0.108 in stage I and 0.918 +/- 0.114 vs 0.975 +/- 0.098 in stage II respectively; p < 0.05, ANOVA). After weaning, lumbar spine and femoral neck bone density increased by 6% and 8% respectively (p < 0.05, ANOVA). No correlation was found between changes in bone turnover markers or bone density and parity, frequency and duration of nursing episodes, body weight, body mass index, and plasma PRL, E2 and PTH levels. We conclude that in nursing women with a daily calcium intake at the recommended dietary allowance ( > 1200 mg/day), full breastfeeding extending over 6 months is characterized by increased maternal bone turnover and a transient bone loss which normalizes after weaning.

Diminished luteinizing hormone biopotency in breastfeeding women

The effect of nursing on plasma luteinizing hormone bioactivity (B-LH) and immunoactivity (I-LH) was assessed at 4 and 6 months post partum in fully nursing women who experienced their first bleeding between months 5 and 6 post partum (n = 6, short amenorrhoea) or after the month 6 (n = 10, long amenorrhoea). Controls were 10 non-nursing fertile women. Blood samples were drawn twice weekly at month 4 post partum and at month 6 post partum. In the nursing women who were cycling at month 6 and in non-nursing women samples were drawn during the follicular phase. I-LH was measured by a time resolved immunofluorometric assay (DELFIA) and B-LH by the mouse Leydig cell assay. Nursing decreased B-LH more than I-LH resulting in a relationship between B-LH and I-LH different to that of non-nursing women (B-LH = 2.84 x I-LH-0.16 and B-LH = 4.27 x I-LH + 3.11 respectively, P < 0.05, by likelihood test). Plasma B-LH or I-LH were similar in nursing women with short or long amenorrhoea. In conclusion, nursing alters the quality of circulating LH, however, the decreased LH steroidogenic potency does not play a role in determining the duration of lactational amenorrhoea.

Luteinizing hormone pulsatile release and the length of lactational amenorrhoea

The pattern of luteinizing hormone (LH) pulsatile release and the mean concentrations of follicle-stimulating hormone, oestradiol and progesterone were studied in nursing and non-nursing women. Blood samples were drawn at 5 min intervals between 10:00 and 14:00 h and between 22:00 and 02:00 h at months 3-4, 5-6, 7-8 and 9-10 postpartum in nursing women and in the follicular phase in non-nursing women. In nursing women, mean LH concentrations at months 3-4 were significantly lower than in non-nursing cycling women only in the subgroup which subsequently experienced > 6 months of lactational amenorrhoea, although all were fully nursing with a similar suckling frequency. LH pulses in plasma were found at all times in nursing women. There were no significant differences in the frequency (about four pulses every 4 h), amplitude or duration of LH pulses related to the duration of amenorrhoea, nor did these parameters vary significantly between amenorrhoeic or cycling nursing women and non-nursing women. Nursing amenorrhoeic women exhibited a normal frequency of LH pulse well in advance of the resumption of the first post-partum menses, suggesting that mechanisms other than the suppression of the gonadotrophin-releasing hormone pulse generator intervened in the inhibition of ovarian function during lactation.

Breast-feeding duration and growth of fully breast-fed infants in a poor urban Chilean population

The duration of breast-feeding and the growth of fully breast-fed infants during the first year of life were analyzed according to sex, birth weight, characteristics of the mother, and breast-feeding pattern. All infants (n = 1217) were healthy and fully breast-fed at 30 d postpartum and 63% and 24% were still fully breast-fed at 6 and 12 mo, respectively. The median ages at introduction of nondairy food and of milk supplements were 6.0 and 7.4 mo, respectively. The probability of remaining fully breast-fed for 12 mo was significantly higher in infants with higher birth weight and higher maternal weight, and in infants who breast-fed seven times a day or more in the first 6 mo. The comparison of the monthly weight and length of fully breast-fed infants with the World Health Organization/National Center for Health Statistics reference data showed the adequacy of breastfeeding to support infant growth. When mothers and infants are healthy, breast milk is sufficient to support adequate infant growth and health during the first months of life. The main variables that affect the duration of breast-feeding, nutrition and suckling frequency, are susceptible to interventions by health services. The results reinforce the need to care for maternal nutrition during pregnancy and to provide the support that women need to sustain a high suckling frequency.

Risk of diarrheal disease in Ecuadorian day-care centers

To determine the risk for diarrheal disease (DD) in day-care centers (DCC) for children residing in a poor urban slum area of Quito, Ecuador, compared with that for children from the same environment but cared for in their own residential home (RH), a prospective age-, sex- and locale-controlled study of DD was conducted, including 115 children in DCC and 115 in RH, ages 12 to 42 months. The overall incidence of DD was 46/1000 child weeks. Diarrhea was more common in DCC than in RH (relative risk (RR), 1.75; 95% confidence interval (CI), 1.38 to 2.22; P < 0.001). Poor hygienic practices were more prevalent in DCC than in RH. The use of reused water for child handwashing before eating and for washing raw vegetables was associated with a higher risk of DD in DCC than in RH (RR = 4.08, CI 2.93 to 5.67, P < 0.001; RR = 3.90, CI 2.79 to 5.44, P < 0.001, respectively). These two practices were risk factors in the DCC (RR = 2.74, CI 2.08 to 3.68, P < 0.001; RR = 2.05, CI 1.55 to 2.71, P < 0.001, respectively) when compared with their absence in the same DCC. Shigella (RR = 3.58, CI 1.19 to 10.78, P < 0.02), Aeromonas (RR = 10.47, CI 1.35 to 81.05, P < 0.01), rotavirus (RR = 2.86, CI 1.87 to 4.39, P < 0.001) and Giardia (RR = 1.59, CI 1.00 to 2.59, P < 0.05) were more common in DCC than in RH. More than two-fifths of the Shigella and Aeromonas isolates were resistant to trimethoprim-sulfamethoxazole.(ABSTRACT TRUNCATED AT 250 WORDS)

[Electrolytic changes in children with acute lymphoblastic leukemia during remission induction]

The alterations of the water-electrolyte balance are among the commonest early complications of treatment in children with acute lymphoblastic leukaemia (ALL). A study was carried out in thirteen patients with ALL aged between 1.5 and 14 years. Four had high risk ALL and nine had standard risk ALL. All patients received intravenous epirubicin and vincristine, per os prednisone, allopurinol and bicarbonate, and intrathecal methotrexate and hydrocortisone. Venous blood was drawn before starting therapy and on days second and sixth of treatment in order to assay sodium, potassium, calcium, phosphate, magnesium, albumin, urea nitrogen, creatinine and uric acid concentrations. The following alterations were found: hyponatraemia in 4 cases, hypokalemia in 9, hypomagnesaemia in 9, hypocalcaemia in 11, hypophosphataemia in 9, hypouricemia in 3 and hyperuricaemia in 3 others. None of the patients developed acute renal insufficiency. These abnormalities could be due to the leukaemia itself or appear as a consequence of the remission induction treatment.

Neuroendocrine mechanisms of lactational infertility in women

The current knowledge on the mechanisms of lactational infertility, discussed during a symposium of investigators in this subject, is reviewed. Three periods of lactation are examined: the first weeks postpartum, the period of extended lactational amenorrhea and the recovery of ovarian function. In the first postpartum weeks the inhibition of ovarian function is accounted by diminished pituitary response to GnRH, since exogenous GnRH fails to elicit a LH increase. Suckling can extend the period of ovarian inhibition for weeks, months or years, although it does not fully suppress pulsatile secretion of LH beyond the first weeks. Extended lactational amenorrhea is associated with low LH plasma levels, a great PRL increase in response to suckling, low basal E2 levels and a suppression of estrogen positive feedback. Decreased immunoreactive LH levels may result from partial suppression of the LH pulse generator and a smaller mass of GnRH released in each burst. The role of neurotransmitters, PRL and ovarian factors is discussed. After the recovery of ovulatory cycles suckling still has a residual infertility effect, associated to inadequate luteal function. The sources of variation among women and populations were recognized. Areas in which research is needed to improve the understanding of the mechanisms that sustain lactational amenorrhea are suggested.

Clinical trial with Nestorone subdermal contraceptive implants

The clinical performance and the in vivo release rate of a single 4-cm Nestorone subdermal implant were investigated. Implants manufactured by two different procedures were compared. Volunteers were 70 healthy women of proven fertility. Forty women provided blood samples twice a week in the pretreatment cycle and for 5-6 weeks at 6-month intervals during treatment. Additional control cycles (n = 31) were studied in 19 Copper T users. No pregnancy occurred in 1570 woman-months. Nestorone plasma levels (x +/- S.E.) declined from 112 +/- 8 to 86 +/- 3 pmol/L (Implant A) and from 145 +/- 8 to 57 +/- 5 pmol/L (Implant B) from the first to the 24th month. Progesterone levels were < 9.5 nmol/L in 166 (93%) of 178 blood samplings taken during treatment. Progesterone levels > 16 nmol/L were found in only 7 sampling periods (3.9%) in treated women and in 70 (98.6%) out of 71 control cycles. No ovulation occurred with Nestorone plasma levels above 105 pmol/L. No abnormal changes were observed in plasma lipoproteins or other clinical chemistry parameters during treatment. The implants were well tolerated. The most frequent complaint was the occurrence of irregular bleeding. Enlarged follicles found during pelvic examination in 8 subjects (11.4%) disappeared spontaneously in 10 days to 6 weeks. Implants were removed because of medical (n = 10, 14.3%) or personal reasons (n = 6, 8.6%) or at the 24th month of treatment (n = 54, 77.1%). The estimated average daily in vivo release rate of Nestorone was 45-50 micrograms/day. A single Nestorone subdermal implant affords efficient contraceptive protection during two years.

Nasal CPAP during wakefulness increases intraocular pressure in glaucoma

Few important side-effects of nasal continuous positive airway pressure (nCPAP) have been reported. No increase of intraocular pressure (IOP) complicating this treatment has previously been described. The goal of our study was to analyse the influence of nCPAP on IOP. We evaluated 18 patients previously diagnosed as having glaucoma and 22 normal subjects. nCPAP was used during wakefulness, at +12 cmH2O for 15 min. The results showed that nCPAP significantly increases IOP in patients with glaucoma (before nCPAP 20.3 +/- 6.3 mmHg) (mean +/- SEM); after nCPAP 22.3 +/- 5.7 mmHg. We believe that nCPAP might be relatively contraindicated in difficult to manage glaucoma patients, if these results are corroborated.

The human reproductive pattern and the changes in women's roles

A broader evolutionary perspective and an understanding of our reproductive behavior in the context of a constantly changing society can contribute to the debate on breastfeeding and reproductive roles of both women and men. Breastfeeding is women's work and should be valued as such. Families and societies need to accept their share of the task of supporting women to breastfeed, to include favorable conditions at the workplace, adequate health care, better nutrition, and recognition of the woman's role and importance.

Prolactin bioactivity and the duration of lactational amenorrhea

In our population, only half of fully nursing women remain amenorrheic 6 months postpartum. The other half recover their menstrual cycles between 90-180 days postpartum in spite of a high suckling frequency and elevated immunoreactive PRL (IR-PRL) concentrations. To further investigate the association of PRL with the recovery of ovarian function, we compared PRL bioactivity (BIO-PRL) 3-4 months postpartum in fully nursing amenorrheic women who subsequently experienced long (> 180 days; n = 5) or short (< 180 days; n = 5) lactational amenorrhea. In the present study, BIO-PRL in plasma was measured by the Nb2 lymphoma cell assay in samples taken before and 30 min after a suckling episode at 0800, 1600 and 2400 h. Women in the long amenorrhea group had higher overall mean BIO-PRL (mean +/- SE, 129.9 +/- 12.1 micrograms/L) than nursing women in the short amenorrhea group (66.6 +/- 5.2 micrograms/L; P < 0.05). Mean basal values were similar, but the women in the long amenorrhea group had more BIO-PRL in response to suckling (160.1 +/- 4.0 vs. 71.9 +/- 6.7 micrograms/L; P < 0.05). Compared with their respective basal values, nursing women in the long amenorrhea group demonstrated increased BIO-PRL in response to suckling, whereas the other group did not. The relationships between BIO-PRL and IR-PRL were similar in the two groups of nursing women before suckling. However, after suckling, the long amenorrhea group had significantly higher BIO-PRL levels than IR-PRL levels (P < 0.05, by likelihood test) than the short amenorrhea group. This suggests that suckling differentially changes in each group either the composition of PRL present or substances that may modify the bioactivity of PRL in plasma.

Chloramphenicol extraction from milk by using the diphasic dialysis method followed by liquid chromatographic determination

An economical, fast, and simple method for the extraction and liquid chromatographic determination of chloramphenicol (CAP) in milk is described. CAP is extracted by using a recently developed membrane-based method named "diphasic dialysis." CAP is detected and quantitated in the organic solvent used in dialysis without additional cleanup steps by reversed-phase liquid chromatography and UV detection (270 nm). The determination limit of CAP in milk was about 5 micrograms/L, although as little as 1 microgram/L could be detected under optimal working conditions.

[Gastric schwannoma. Report of a case]

Gastric schwannoma is a rare and benign neurogenic tumor. Diagnosis of this entity is uncertain previous to surgery, being this tumor localized in the sub-mucosa. Final diagnosis is achieved by surgical removal and histological examination.

Contraception in lactating women

Lactating women need contraception after first menses, supplementation or 6 months postpartum, or before, according to personal or programmatic reasons. Non-hormonal methods have no influence on lactation and are the first choice. Intrauterine devices (IUDs) inserted during amenorrhea are safe and show good continuation rates. Progestin-only methods do not affect breast-feeding and should be used after 6 weeks to prevent transference of orally active steroids to the newborn. Progesterone rings and Nestorone implants are effective new methods, that use orally inactive steroids.

[Prevention of tuberculosis infection]

Tuberculosis (TB) is a disease caused by a mycobacterium, whose incidence has increased in the past years. This increase is related to the adquired immunodeficiency syndrome (AIDS). Due to its high prevalence, Spain is considered a developing country. The tuberculous infection depends on the degree of functionality of the alveolar macrophages that stimulate the lymphocytes and isolate the bacillus. The infection by mycobacterias can be quantified by means of the cutaneous reaction against tuberculin and mantoux, allowing us to select the subjects that must receive prophylaxis. For its correct interpretation, it is currently recommended to avoid BCG vaccination of children, except in countries with high prevalence of TB.