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Biomedical subjects

F Cano

Publications and source records attributed to F Cano.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Chronic hemodialysis in children].

BACKGROUND: The final objective of every children that is admitted to a program o hemodialysis of peritoneodialysis is to receive a renal graft. AIM: To report the experience in pediatric hemodialysis in two pediatric hospitals in Chile that are reference centers for renal transplantation. PATIENTS AND METHODS: Sixty patients, 55% female, aged 2 to 15 years old, admitted to the dialysis and transplant program since 1987, with a creatinine clearance of less than 20 ml/min/1.73 m2, were studied. RESULTS: Twenty percent of children were less than 5 years old at the moment of admittance to the program and 3.3% weighed less that 10 kg. Etiologies of end stage renal disease were glomerulopathies in 33.4%, reflux nephropathy in 27.7%, obstructive uropathy in 13.3%, hypoplasia/dysplasia in 10%, hereditary problems in 8.3% and vascular disorders in 5%. Eighty six percent of patients were dialyzed less than 2 years and 5% more than 4 years. Fifty percent had received prior medical treatment, 5% had been treated with intermittent peritoneal dialysis, 5% with chronic ambulatory peritoneal dialysis and 20% presented as a terminal renal failure. Sixty two percent received a renal graft, 25% is still on hemodialysis, 3.3% switched to chronic ambulatory peritoneal dialysis, 3.3% had a recovery of renal function and 6.7% died being on hemodialysis. Arterio-venous fistulae were the vascular accesses in 75% of patients, double lumen catheters in 50% and vein grafts in 5%. Malfunctioning or infections were the main complications of arterio-venous fistulae, accounting for 30% of hospital admissions. CONCLUSIONS: The availability of new vascular accesses and new hemodialysis machines specially designed for children, along with specially trained health care personnel, should reduce the mortality and complication rates of hemodialysis in this age group.

Adolescent↗
PubMed1997

Oocyte quality in polycystic ovaries revisited: identification of a particular subgroup of women.

PURPOSE: Our purpose was to assess the endocrine status of women with polycystic ovaries (PCO) undergoing IVF, and to compare oocyte quality with endocrine markers of the syndrome, in an attempt to define a subpopulation with poor quality oocytes. METHODS: This was a retrospective study. Patients were first endocrinologically analyzed: serum levels of androgens (T, androstenedione, DHEAS), FSH, and LH as well as glucose and insulin after an oral glucose tolerance test (OGTT) were recorded and are expressed as absolute values and area under the curve (AUC). Subsequently, they were followed over a 2-year period in which patients underwent several attempts of IVF as well as serving as oocyte donors. Patients were divided into three groups: group I (n = 4) was women who displayed embryos unable to implant in 15 IVF cycles and 10 ovum donation cycles in which they served as donors; group II (n = 16) was PCO patients in whom IVF (n = 38) and/or oocyte donation cycles (n = 42) resulted in pregnancies; and group III (n = 13) was IVF patients with normal appearance of the ovaries by ultrasound. The endocrine status was compared with the IVF results. RESULTS: There was no difference among groups in the endocrinological parameters tested, except for the OGTT which identified women in group I as having higher serum glucose and insulin levels than patients in groups II and III. Similarly, the OGTT showed higher serum glucose values in group II compared to group III. Women in group I were also obese. Patients in group III were older than PCO patients and needed more gonadotropins to reach an ovarian response which resulted in a reduced number of oocytes retrieved. Fertilization was also impaired in group I, in which no pregnancy was recorded. CONCLUSIONS: This study shows that there is a particular subgroup of PCO patients with lower fertilization rates and embryos unable to implant. These patients are obese and nonhyperandrogenic and show derangements of insulin secretion.

Adult↗
PubMed1996

Lower implantation rates in high responders: evidence for an altered endocrine milieu during the preimplantation period.

OBJECTIVE: To determine serum E2 and P levels around the time of implantation in normal and high IVF responders. SETTING: In Vitro Fertilization program at the Instituto Valenciano de Infertilidad. PATIENTS: Twenty-nine women undergoing IVF, who accepted to be studied daily, were classified according to the number of oocytes retrieved in normal (n = 16) and high responders (n = 13). DESIGN: Prospective study in which blood was drawn daily from the day of hCG administration (day 0) up to 7 days later (day 6). MAIN OUTCOME MEASUREMENTS: In vitro fertilization parameters (number of ampules, FSH-hMG, number of oocytes, fertilization rates, number of transferred embryos, implantation rates, and pregnancy rates); serum E2 and P levels during the 7 days of the study. RESULTS: Implantation rate was significantly higher in normal (18.5%) as compared with high (0%) responders. Estradiol and P levels were elevated significantly in high responders. The E2:P ratio was significantly different between normal and high responders during the preimplantation period. Pregnancy and implantation rates decreased as serum E2 levels increased on days 4 to 6 of the study. CONCLUSIONS: A different endocrine milieu between normal and high responders is detected by daily steroid measurements up to the preimplantation period, suggesting that this difference could be responsible for an impaired implantation in high responder patients undergoing IVF. An increase in serum E2 levels seems to be the cause of this difference.

Chorionic Gonadotropin↗
PubMed1996

Epidemic cholera in Guatemala, 1993: transmission of a newly introduced epidemic strain by street vendors.

Epidemic cholera reached Guatemala in July 1991. By mid-1993, Guatemala ranked third in the hemisphere in reported cases of cholera. We conducted a case-control study with two age-, sex-, and neighbourhood-matched controls per patient in periurban Guatemala City. Twenty-six patients hospitalized for cholera and 52 controls were enrolled. Seven (47%) of 15 stool cultures obtained after admission yielded toxigenic Vibrio cholerae O1. All seven were resistant to furazolidone, sulfisoxazole, and streptomycin, and differed substantially by pulsed-field gel electrophoresis from the Latin American epidemic strain dominant in the hemisphere since 1991. In univariate analysis, illness was associated with consumption of left-over rice (odds ratio [OR] = 7.0, 95% confidence interval [CI] = 1.4-36), flavored ices (-helados') (OR = 3.6, CI = 1.1 - 12), and street-vended non-carbonated beverages (OR = 3.8, CI = 1.2-12) and food items (OR = 11.0, CI = 2.3-54). Street-vended food items remained significantly associated with illness in multivariate analysis (OR = 6.5, CI = 1.4-31). Illness was not associated with drinking municipal tap water. Maintaining water safety is important, but slowing the epidemic in Guatemala City and elsewhere may also require improvement in street vendor food handling and hygiene.

Adolescent↗
PubMed1995

Calcitriol oral pulse therapy in children with renal osteodystrophy.

A 6-month protocol of oral pulse calcitriol was used in nine uraemic children (2-14 years old) on dialysis who presented with renal osteodystrophy. Calcitriol was administered twice a week, 4 micrograms per dose for patients over 30 kg and 3 micrograms for patients less than 30 kg. Plasma levels of parathyroid hormone, calcium, phosphorus and alkaline phosphatase were carefully controlled during the study. Parathyroid hormone levels decreased by 68% and 56% by the 2nd and 6th months of treatment in seven patients, while they remained unchanged in two patients with focal segmental glomerulosclerosis and massive proteinuria. Eight hypercalcaemic episodes from 77 determinations were observed, all of them recovered after 1 week of vitamin D withdrawal. We conclude that oral calcitriol pulse therapy is a good alternative for renal osteodystrophy in uraemic children. Careful monitoring of plasma parathyroid hormone and calcium is needed during follow-up when using this approach in paediatric patients.

Administration, Oral↗
PubMed1995

Effect of aging on the female reproductive system: evidence for a role of uterine senescence in the decline in female fecundity.

OBJECTIVE: To determine the effects of age on reproductive performance of women using oocyte donation as an in vivo model. SETTING: Oocyte donation and IVF programs at the Instituto Valenciano de Infertilidad. PATIENTS: Seventy-six women undergoing 90 cycles of ovum donation, who were recipients of 36 donors undergoing IVF, and 9 fertile women. DESIGN: Prospective longitudinal study: [1] recipients underwent an artificial cycle to demonstrate adequate response of the endometrium to exogenous steroids; [2] oocytes from the same cohort of follicles were distributed randomly into recipients younger and older than 40 years; and [3] pregnancies were followed during the first trimester. MAIN OUTCOME MEASURES: Endometrial histology, fertilization, embryo quality, pregnancy, implantation, and abortion rates in both groups of recipients. Serum E2, P and beta-hCG levels during initial pregnancy. RESULTS: Similar implantation rates but significantly higher abortion rates were detected in women > 40 years despite an appropriate action of P on the endometrium and the transfer of embryos in similar number and quality. The secretion of E2 and P by the placenta started earlier in pregnancies included in the group < 40 years. CONCLUSIONS: Age increases pregnancy losses in ovum donation patients after implantation is completed. This is accompanied by a retardation of steroid synthesis and suggests that the mechanism(s) responsible for placenta formation and functioning in the uterus is affected by age. Thus, uterine aging also is a factor influencing the poor reproductive performance of women with advancing age.

Adult↗
PubMed1995

Long oestradiol replacement in an oocyte donation programme.

The objective of this study was to optimize, in terms of endometrial receptivity (embryo implantation), the limits of unopposed administration of oestrogens beyond 35 days in an in-vitro fertilization (IVF) and ovum donation programme. Oocytes donated by 182 women undergoing IVF were distributed among 186 women treated by ovum donation. Five groups of recipients were established according to the duration of oestradiol valerate administration, in a 'prolonged follicular phase' protocol, before embryo replacement, employing oestradiol valerate at increasing doses up to 6 mg/day. Gonadotrophin-releasing hormone analogues (GnRHa) were simultaneously administered in ovulatory patients. The dosage of oestradiol valerate was maintained until oocytes were available for insemination and subsequent transfer. Donors and recipients were equally distributed among groups in terms of age and cause of infertility. There was no difference among groups in serum oestradiol concentration the day in which progesterone was added to obtain a secretory transformation of the endometrium. An analysis of the ovum donation cycles showed no difference among groups in pregnancy and implantation rates after the replacement of a similar number of embryos. Successful implantation was observed even after 100 days of unopposed oestradiol valerate administration. Break-through bleeding increasingly appeared according to the duration of oestrogen replacement. These clinical observations provide evidence that the concept of 'prolonged follicular phase' oestrogen replacement for ovum donation can be maintained, at least as long as 15 weeks. However, because of the high (> 44%) incidence of break-through bleeding after 9 weeks, it is advisable to stop oestrogen treatment at this point.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Clinical evidence for a detrimental effect on uterine receptivity of high serum oestradiol concentrations in high and normal responder patients.

This study was undertaken to investigate an empirical observation that 'high responder patients have poorer in-vitro fertilization (IVF) outcome than normal responder patients'. The aim of our study was to analyse the effect of high serum oestradiol and progesterone concentrations at the day of human chorionic gonadotrophin (HCG) administration on endometrial receptivity and oocyte-embryo quality in high and normal responder patients. The IVF patients were divided into two groups: 59 high responder patients who voluntarily donated some of their oocytes, and a control group consisting of 105 normal responder patients. Both groups were compared in terms of the number and quality of oocytes retrieved, embryos transferred, fertilization, implantation and gestation rates, serum oestradiol and progesterone concentrations and the oestradiol:progesterone ratio on the day of HCG injection. To ascertain oocyte-embryo quality, a second control group of 96 women undergoing oocyte donation (receiving oocytes from high responder patients) was considered. To assess the impact of steroid concentrations on endometrial receptivity, high responder patients were divided into two subgroups according to oestradiol concentration, above or below the minimal oestradiol and progesterone concentrations (mean--SD) in this group. The normal responder patients were divided into two subgroups according to oestradiol concentration, above or below the maximal oestradiol and progesterone concentrations (mean+SD) in this group. To assess further the relevance of oestradiol concentration on endometrial receptivity, patients were divided into different subgroups according to increasing oestradiol concentration, regardless of whether they were high or normal responders. High responder patients had significantly decreased implantation and pregnancy rates per cycle compared with normal responder patients (33.3 versus 16.3 and 11.1 versus 5.4% respectively; P < 0.05). The results of 108 embryo transfers in 91 recipients who received oocytes from the high responder group showed normal embryo quality. Implantation rates and pregnancies per cycle were significantly lower in high responder patients with serum oestradiol concentrations > 1700 pg/ml compared with those having oestradiol concentrations < or = 1700 pg/ml, as well as in normal responder patients with serum oestradiol concentrations > 2200 pg/ml compared with those having oestradiol concentrations < or = 2200 pg/ml. Considering all the patients together, significant decreases in pregnancy and implantation rates were observed when oestradiol concentrations were > 2500 pg/ml compared with patients having lower oestradiol concentrations. Our clinical results demonstrate that high serum oestradiol concentrations on the day of HCG injection in high and normal responder patients, regardless of the number of oocytes retrieved and the serum progesterone concentration, are detrimental to uterine receptivity without affecting embryo quality.

Chorionic Gonadotropin↗
PubMed1995

Fecal excretion of leukotriene C4 during human disease due to Shigella dysenteriae.

Fecal excretion of leukotriene C4 was determined in 26 individuals with dysentery and in 19 healthy controls. Of the patients, five were infected with Shigella dysenteriae type 1, 15 were infected with Shigella flexneri, two were infected with Shigella boydii, and four were infected with Shigella sonnei. Three of the healthy controls were infected with non-dysenteriae Shigellae. All isolates of Shigella dysenteriae type 1 produced Shiga toxin; the other strains were not toxigenic. Patients with dysentery due to Shigella dysenteriae type 1 excreted higher concentrations of leukotriene C4 (median, 3,234 pg/0.05 g of feces) than either ill individuals infected with non-dysenteriae Shigellae (median, 202 pg/0.05 g) or healthy carriers (median, 145 pg/0.05 g) and uninfected controls (median, 129 pg/0.05 g). We propose that Shiga toxin stimulates intestinal mast cells, which release leukotriene C4, contributing to the inflammatory response in Shigella dysenteriae type 1-associated dysentery.

Adult↗
PubMed1994

Infection, diarrhea, and dysentery caused by Shigella species and Campylobacter jejuni among Guatemalan rural children.

To examine the factors that may influence the outcome of infections by Shigella spp. and Campylobacter jejuni we followed for 24 consecutive months 321 rural Guatemala children 0 to 35 months old. Home visits were made to determine child morbidity patterns with emphasis on diarrhea and dysentery. Fecal samples for microbiologic studies were obtained from the participants when they were ill and during healthy periods. Shigella spp. were isolated from 9.8 and 4.0% of ill and healthy children, respectively; the figures for C. jejuni were 12.1% and 8.1%. Shigella flexneri 1, 2 and 6 and Shigella sonnei accounted for 70% of all Shigella isolates. Twenty-four percent of Shigella spp. and 7% of C. jejuni infections resulted in dysentery. Shigella dysenteriae and Shigella flexneri were more likely to induce dysentery than the other species. The incidence of dysentery was 0.84 of 100 child weeks. Age, gender, nutritional status and feeding habits of the children did not affect the outcome of Shigella infection. Fat consumption favored the development of dysentery caused by C. jejuni. The development of dysentery seems to be associated with microbial factors and not with host variables, although specific Shigella serotype protection against symptomatic infection may be functional for prolonged periods after natural exposure.

Campylobacter Infections↗
PubMed1993

[Esophageal stenosis due to a dissecting intramural hematoma following the endoscopic sclerotherapy of esophageal varices].

The dissecting intramural hematoma of the esophagus (DEH) is a rare complication of endoscopic variceal sclerotherapy (EVS). We present a 37 years male with Laennec's cirrhosis who developed a submucosal hematoma with complete obstruction of the esophagus 24 h. after the second session of EVS diagnosed by endoscopy. After conservative treatment the patient recovered well with complete resolution of the lesion. The review of the literature shows no correlation between DEH and type or volume of sclerosant, site of injection or previous number of sessions. Unknown in children. Most of these patients had abnormal hemostasis. We have performed EVS in 227 patients (879 sessions), with only a case of DEH (rate 0.13%). In this case the bad tolerance and movements during of EVS were very important.

Adult↗
PubMed1992

Oral gentamicin is not effective treatment for persistent diarrhea.

We conducted a randomized, double-blind, placebo controlled clinical trial of oral gentamicin (10 milligrams/kilogram body weight/day for five days) in treatment of unselected cases of persistent diarrhea (duration 14-18 days at initiation of treatment) among 3-36-month-old children in a rural Guatemalan community. Following random assignment of each child to a treatment group, the appropriate dose of gentamicin or placebo was administered to the child three times daily by a study nurse; this nurse also identified the presence or absence of diarrhea on each day of treatment and for the next two days. Cure was defined as cessation of diarrhea during the five-day treatment period, sustained through at least the two days after completion of treatment. Among 92 evaluable cases who entered the clinical trial, there was essentially no difference in cure rate between gentamicin and placebo treatment groups (42% versus 43%). Enteroadherent strains of Escherichia coli were identified in 46% of children tested in this trial; no significant difference existed between treatment groups in frequency of isolation of this or any other enteropathogen. Among 40 children having successful duodenal cultures immediately prior to beginning treatment, > or = 10(4) aerobic organisms per milliliter of fluid were identified in 12 (30%); treatment groups did not differ substantially with respect to proportion of children identified with this level of duodenal microbial colonization. Failure of gentamicin treatment did not appear to be explained by emergence of resistance, although a small number of resistant enteropathogens were identified near the end of the study.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1992

Astrovirus-associated diarrhea among Guatemalan ambulatory rural children.

Fecal excretion of astroviruses was monitored in 321 children, 0 to 3 years old, living in the rural highlands of Guatemala. During the longitudinal study, from February 1987 to February 1989, we examined 5,000 stool specimens, including 1,805 collected during 1,369 episodes of diarrhea, 830 collected during the convalescent week, and 216 and 244 collected 2 weeks and 1 week, respectively, before the onset of diarrhea. Routine specimens were taken once a month from every child who had been free from diarrhea for at least three consecutive weeks. Of the children, 124 (38.6%) excreted astroviruses during the study. In total, we identified 184 infections by astroviruses. Of the samples collected 2 weeks and 1 week before the initiation of symptoms, 0.9 and 4.9%, respectively, were positive, while 7.3% of the diarrhea episodes were associated with astroviruses. Of the convalescent specimens, 3.4% were shown to be positive; 2.4% of the 1,905 specimens taken in diarrhea-free periods contained astroviruses. Infections by other potential enteropathogens were documented in 54 and 65% of the asymptomatic and symptomatic astrovirus infections, respectively. Diarrhea associated with astroviruses alone had a median duration of 5 days and was associated with vomiting in 8.6%, with fever in 17.1%, with dehydration in 5.7%, and with loss of appetite in 34.3% of the episodes. Diarrhea due to astroviruses was accompanied by negative changes in weight gain. Astrovirus diarrhea contributes to the high morbidity observed in young children living under poor conditions and has a deleterious effect on their nutritional status.

Body Weight↗
PubMed1992

[Neurotoxicity caused by cyclosporin A in renal transplantation in children].

Cyclosporine is a specially useful immunosuppressor agent in children subjected to renal transplantation, minimizing the deleterious effect of steroids on growth and the development of Cushing syndrome. However, side effects which require close supervision are well known, including liver, kidney and central nervous system toxicity. Seizures, cerebellar ataxia, aphasia, paresthesia and behavioral disorders are characteristic of the latter. Hypertension and hypomagnesemia have been identified as risk factors. In contrast to nephrotoxicity, CNS toxicity is not related to plasma levels of cyclosporine. In this paper 2 patients, 10 and 11 year old, manifesting cyclosporine neurotoxicity after renal transplant, are reported.

Brain Ischemia↗
PubMed1990

Absent specific viral antibodies in patients with transient hypogammaglobulinemia of infancy.

Of 247 patients referred to the Pediatric Immunology Clinic, University of Connecticut Health Center, Farmington, Conn., for recurrent infections, 13 patients were found to have an abnormal delay in the onset of IgG synthesis and prolongation of the physiologic hypogammaglobulinemia of infancy. At first observation, their mean age was 10.6 months. All patients had abnormally low serum IgG levels (less than or equal to 2 SD for their age). The mean serum IgG level for our patient population was 270 +/- 81 mg/dl; the mean serum IgG level of the control group was 749 +/- 440 mg/dl. Clinically, these patients were first observed with recurrent otitis media, respiratory infections, bronchitis and/or asthma, and formula intolerance. Despite recurrent respiratory tract infections, specific antibodies to the respiratory viruses were absent in nine of 11 patients tested who were observed before 17 months of age. On follow-up, two of the 13 patients never developed specific antibodies to viral agents, although their serum IgG levels normalized; one patient became serology positive at the same time that the serum IgG normalized. In two patients, the serum IgG levels returned to within the normal range for age before the appearance of specific viral antibodies. In eight patients, the appearance of specific viral antibodies was detected before the serum IgG levels returned to normal. Five of these eight patients were treated for short periods (9 months) with replacement immune serum globulin (intramuscular) therapy and did clinically well. These observations suggest that replacement immune serum globulin for short periods of time does not appear to suppress the production of specific, naturally occurring antibodies and the resolution of the hypogammaglobulinemia.

Agammaglobulinemia↗