Genetic differences in HLA-DQA1* and DQB1* allelic distributions between celiac and control children in Santiago, Chile

Celiac disease is a permanent gluten intolerance strongly associated with HLA class II antigens. The over presentation of particular HLA alleles and haplotypes has been described in several populations. Different lines of evidence obtained during the last years suggest that a particular HLA-DQ heterodimer, encoded by the DQA1*0501 and DQB1*0201 genes in cis or trans conformation, confers the primary disease susceptibility. We report the HLA class II allelic distribution and DQA1/ DQB1 genotypes in 62 Chilean celiac patients compared with 124 control subjects in Santiago, Chile. We found a pronounced increase of the "susceptible" alleles :DQA1*0501 (0.480 vs 0.169, Pc < 0.0005), DQB1*0302 (0.430 vs 0.242, Pc = 0.002) and DQB1*0201 (0.250 vs 0.125, Pc = 0.037) in celiac patients in comparison with control children. As for "protective" alleles, we detected a high frequency of DQA1*0101 (0.310 vs 0.160, Pc = 0.01), DQA1*0201 (0.105 vs 0.010, Pc < 0.0075) and DQB1*0301 (0.250 vs 0.100, Pc = 0.010) in controls. In relation to risk haplotypes, the main combination observed was the conformation DQ8 (DQB1*0302/DQA1*0301) over DQ2 (DQB1*0201/DQA1*0501). In conclusion, results show that celiac disease in Chilean patients is primarily associated with DQ8 conformation. This is concordant with the high frequency of DR4 alleles (in linkage disequilibrium with DQB1*0302) detected in Amerind groups in Chile, where DQB1*0302 is more frequent than DQB1*0201.

[Pharmacokinetic analysis of low-dose intra-peritoneal cis-platinum administration]

Pharmacokinetic parameters after intra-peritoneal administration of low-dose cis-platinum (CDDP) were analysed in order to evaluate the possibility of applying low-dose 5-FU/CDDP therapy (1-FP) for outpatients. Four patients with advanced gastric cancer were the subjects of this study. CDDP at a dose of 20 mg/body was administered intra-peritoneally, and peripheral venous blood was collected at 30 min, 4, 8, 24, 48, 72, 96 and 120 hr after drug administration. The plasma platinum (Pt) concentration was determined by atomic absorption spectrometry. Pharmacokinetic parameters were calculated using a two-compartment open model. C max, AUC, t1/2 alpha and t1/2 beta of total-Pt were 1. 27 +/- 0.21 micrograms/ml, 95.28 +/- 16.93 micrograms.hr/ml, 1.91 +/- 0.76 hr and 190.2 +/- 125.6 hr, respectively. Total-Pt concentration at 120 hr, after administration was 0.54 +/- 0.14 microgram/ml. This result suggests that intraperitoneal low-dose CDDP administration is a promising method for 1-FP therapy for outpatients, because the plasma total-Pt level is maintained at a sufficiently high level for a long period.

Carcinoembryonic antigen level in peritoneal washing is a prognostic factor in patients with gastric cancer

This study was designed to evaluate the usefulness of carcinoembryonic antigen (CEA) and sialyl-Tn antigen (STN) levels in peritoneal washings in gastric cancer patients. At the time of laparotomy, peritoneal washings were collected from 96 gastric cancer patients and CEA and STN levels were determined. Patients with elevated CEA (100 ng/g protein) had a high incidence for peritoneal metastasis, lymph node metastasis and serosal invasion. In addition, prognosis in patients with high CEA level was significantly poorer than in those without it. The peritoneal CEA is a prognostic factor in patients with gastric cancer.

Microvessel count predicts metastasis and prognosis in patients with gastric cancer

BACKGROUND AND OBJECTIVES

In order to evaluate the clinical relevance of angiogenesis in patients with gastric cancer, we investigated the microvessel count in gastric cancer tissues and compared the results with several clinicopathologic factors and prognosis.

METHODS

A total of 55 patients with gastric cancer were included in this study. Microvessel count was determined by immunohistochemical staining using antifactor VIII-related antigen antibody. Histologically recognizable blood vessels within tissue sections served as internal control for immunostaining. Normal mouse IgG diluted to an equivalent protein concentration was used as a negative control in place of the primary antibody in each experiment.

RESULT

The microvessel count ranged from 4.4 to 39.8 and the median count was 15.6. Microvessel count was significantly higher in patients with hepatic metastasis, lymph node metastasis, adjacent organ invasion, and lymphatic invasion. In patients who had undergone a curative operation, survival time in the hypervascular group was significantly shorter than that in the hypovascular group.

CONCLUSIONS

Microvessel count correlated well with tumor progression and may serve as a useful prognostic factor in patients with gastric cancer.

[Pharmacokinetic analysis of intra-peritoneal administration of cisplatin]

Pharmacokinetic parameters after intra-peritoneal administration of cis-platinum (CDDP) were evaluated and compared with those after intravenous administration. CDDP at a dose of 70 mg/m2 were administered intra-peritoneally in 5 patients with advanced gastric cancer (IP group). Pharmacokinetic parameters and toxicities were evaluated in these patients and compared with those in 4 esophageal cancer patients administered the same dose of CDDP intravenously (IV group). In IP group, Cmax of total- and free-Pt were 3.41 +/- 0.89 micrograms/ml and 1.10 +/- 0.30 micrograms/ml, and AUC of total- and free-Pt were 59.6 +/- 14.3 micrograms.hr/ml, 3.12 +/- 0.89 micrograms.hr/ml, respectively. On the other hand, Cmax and AUC of total- and free-Pt in IV group were 3.31 +/- 0.59 micrograms/ml. 1.13 +/- 0.21 micrograms/ml and 45.89 +/- 9.24 micrograms.hr/ml, 1.22 +/- 0.8 micrograms.hr/ml, respectively. AUC of free-Pt in IP group was significantly higher than in IV group. This result suggests that a more promising antitumor effect will be obtained systemically by intraperitoneal administration of CDDP. The incidence and grade of toxicities were similar in these two groups.

Microvessel count predicts metastasis and prognosis in patients with gastric cancer

BACKGROUND AND OBJECTIVES

In order to evaluate the clinical relevance of angiogenesis in patients with gastric cancer, we investigated the microvessel count in gastric cancer tissues and compared the results with several clinicopathologic factors and prognosis.

METHODS

A total of 55 patients with gastric cancer were included in this study. Microvessel count was determined by immunohistochemical staining using antifactor VIII-related antigen antibody. Histologically recognizable blood vessels within tissue sections served as internal control for immunostaining. Normal mouse IgG diluted to an equivalent protein concentration was used as a negative control in place of the primary antibody in each experiment.

RESULT

The microvessel count ranged from 4.4 to 39.8 and the median count was 15.6. Microvessel count was significantly higher in patients with hepatic metastasis, lymph node metastasis, adjacent organ invasion, and lymphatic invasion. In patients who had undergone a curative operation, survival time in the hypervascular group was significantly shorter than that in the hypovascular group.

CONCLUSIONS

Microvessel count correlated well with tumor progression and may serve as a useful prognostic factor in patients with gastric cancer.

Eggshells are shaped by a precise spatio-temporal arrangement of sequentially deposited macromolecules

The avian eggshell is a composite bioceramic which is formed by a controlled interaction of an organic and an inorganic phase. The organic phase contains, among other constituents, type X collagen and proteoglycans, mainly keratan and dermatan sulfate. Understanding the principles governing the synthesis and temporo-spatial distribution of such macromolecules, and their influence on the organization of the crystalline phase, is an essential aspect of establishing the biological basis of the quality of eggshell, both as an embryonic chamber and as a natural food package. In the present study, we have examined the process of eggshell formation by immunohistochemistry, scanning electron microscopy and energy dispersive X-ray microanalysis. Precise sites and timing of secretion were established for the deposition of particular macromolecules. Type X collagen is detected at the very first moment of shell membrane formation. The appearance of keratan sulfate coincides with the appearance of mammillae, while dermatan sulfate is deposited later, coincident with shell matrix deposition. We propose that keratan sulfate, due to its precise localization, temporal appearance and calcium-binding affinity, relates to the maintenance of calcium reserve bodies, the primary source of calcium for the embryo. On the other hand, dermatan sulfate may control crystal growth, resulting in a preferential orientation of calcite crystals within the palisade layer.

Altered maternal psychological profile as health risk factor in poor urban infants

To test the hypothesis that the increased health risk of children selected by a previously calculated and validated predictive model is associated with some maternal psychological characteristics, the universe of 107 mothers of children selected by this model was evaluated by means of Goldberg's General Health Questionnaire (GHQ-30), Raven (Ra) and Rorschach (Ro) tests; 37.4% were cases according to GHQ-30, 80.9% were < 50th percentile in Ra and 85% exhibited deviant responses in Ro tests. Children whose mother's IQ was < 50th percentile suffered more episodes of total morbidity (Tm) and of diarrhoea (p = 0.0364). Children whose mothers were normal in Ro had less Tm (p = 0.0364) and fewer respiratory symptoms (p = 0.0300) and tended to have less diarrhoea (p = 0.0690). In poor urban families in Santiago psychological maternal characteristics are associated with an increased health risk for the infants. Supportive programmes should consider both biological characteristics of the infants and maternal psychological needs.

[Pharmacokinetic analyses of intra-arterial and intra-portal chemotherapeutic agent infusion]

In order to determine the optimal drug administration route in patients with metastatic liver tumor, we studied the pharmacokinetic parameters after intra-arterial or intra-portal adriamycin (ADM) administration. Four patients with metastatic liver tumors were included in this investigation. One catheter was inserted into the gastroduodenal artery for arterial infusion and the other catheter was inserted into the portal vein via mesenteric vein for portal infusion under laparotomy. ADM 30 mg was infused and blood samples were collected from peripheral and hepatic veins. The concentration of ADM was determined with HPLC technique and the pharmacokinetic parameters were analyzed with a three-compartment open model. The parameters analyzed were blood concentration at t0, half-life, rate of elimination, total body clearance, volume of distribution and area under the blood concentration versus time curve. There were no significant differences of the pharmacokinetic parameters between intra-arterial infusion and intra-portal infusion. Also, no differences were observed between the data from peripheral venous blood and those from hepatic venous blood. These data suggest that the drug distributions were almost similar between intra-arterial and intra-portal drug administration in patients with metastatic liver tumor.

Maternal neurotic symptoms and infants' risk of developing persistent diarrhoea

A previously calculated predictive model for health risk selects infants who suffer 4-5 times more morbidity than their unselected peers. Preliminary results suggested that this risk is related to maternal neurotic symptomatology. To evaluate this hypothesis, 52 consecutive mothers whose infants had a positive predictive score (Group 1) and 52 in whom this was negative (Group 2) were evaluated by means of Goldberg's General Health Questionnaire (GHQ-30). A total of 41.9% and 20.5% of the mothers in Groups 1 and 2, respectively, scored above 11 points in GHQ-30, established as the cut off point. It is concluded that among poor urban families in Santiago mothers of infants with high risk of persistent diarrhoea have increased frequency of detectable neurotic symptoms. New programs aimed at this type of infant should include psychological support for their mothers.

Host Status of Crotalaria juncea, Sesamum indicum, Dolichos lablab, and Elymus glaucus to Meloidogyne javanica

Reproduction of Meloidogyne javanica on Crotalaria juncea PI 207657 and cv. Tropic Sun, Sesamum indicum, Dolichos lablab, and Elymus glaucus was assessed using a root-gall index, a reproductive index obtained by dividing the final population of juveniles (J2) in soil by the initial J2 population (Pf/Pi), and the number of J2 per gram of root recovered from roots by mist chamber extraction. Lycopersicon esculentum (cv. UC 204 C) was included as a susceptible host. The root-gall index and soil reproductive index were poor indicators of the host status of our test plants as compared with mist chamber extraction of J2 from roots. Lycopersicon esculentum had a mean root-gall index of 7.8. Some plants of S. indicum and E. glaucus had a few galls and other plants had none, with mean root-gall indices of 1.6 and 0.8, respectively. No galls were observed in C. juncea and D. lablab. Lycopersicon esculentum had the highest mean soil Pf/Pi value (mean = 1.93), while in C. juncea and some replicates of S. indicum no soil J2 were found. Even though some replicates had no galls, all replicates supported nematode reproduction. The mean numbers of J2 per gram root after 5 days of mist extraction were 447.7, 223.3, 165.5, 96.9, 42.3, and 41.9 for D. lablab, L. esculentum, E. glaucus, S. indicum, and C. juncea PI 207657 and cv. Tropic Sun, respectively. Accurate assessment of nematode resistance was influenced by sampling time and the nematode extraction technique used. Individual plants of both C. juncea and S. indicum supported nematode reproduction to some extent; however, both C. juncea and S. indicum have potential as cover crops to reduce M. javanica numbers.

[Application of a predictive model for morbidity among middle socioeconomic class infants]

A predictive model which identifies infants who suffer 4 to 5 times more morbidity than their unselected peers was calculated in previous studies, in population of the low socio-economic stratum (SES) (Rev Med Chile 1992; 120: 342-8): Some families of the middle SES also seek care at the Primary Health Care System. Therefore, since our aim is to propose an instrument to be used at this level, the predictive model was applied in families of this stratum. Children identified by means of the model suffered as many episodes of diarrhea but not of other illnesses, as their peers of the low SES (4.8 vs 4.3 respectively). Families in whom the instrument was positive were fewer in the middle SES (6.8 vs 15.7%). Because during the study a campaign to prevent cholera was carried out in Santiago, and this may modify the predictor's performance, at the end of the follow up the model was validated again in families of the low-SES; results confirmed that children with a positive predictor suffered more diarrhea than those of the non-selected population (6.5 vs 3.4 episodes/children/year).

Effect of health education and primary care on diarrhoeal disease morbidity in children: evaluation of a predictive intervention model

Two groups of infants (intervention group n = 66, and control group n = 45) at risk of persistent diarrhoea (PD) as identified by a predictive model were followed for 12 months. Families were visited at home weekly; mothers in the intervention group received information about prevention and treatment of diarrhoea and were encouraged to seek help in the field station when their children became ill. These children suffered fewer days with any illness, diarrhoea, or respiratory episodes (p < 0.00001 each). Also, in this group, the incidence of PD decreased to the levels of nonselected population only in children whose mothers consulted for the episode of diarrhoea (2.8%). Results show that the intervention decreased the time children suffered diarrhoea and also respiratory and other illnesses. This suggests that the predictive model identified children with high risk but is not disease-specific. Risk appears to be related to maternal behaviours. The model may be useful in the community for detecting groups vulnerable to common paediatric illnesses, including diarrhoeal disease.

Penetration of Crotalaria juncea, Dolichos lablab, and Sesamum indicum Roots by Meloidogyne javanica

Penetration of Crotalaria juncea (PI 207657 and cv. Tropic Sun) Dolichos lablab cv. Highworth, and Sesamum indicum by juveniles (J2) of Meloidogyne javanica was assessed to investigate the mechanism by which these plants may reduce nematode numbers in the field. Growth chamber experiments were conducted at 25 C, with vials containing 90 g sand infested with 450 J2; tomato (UC 204 C) was included as a susceptible host. Fifteen days after inoculation, roots were stained and the nematodes within stained roots were counted. Both C. juncea lines were highly resistant to penetration, as they contained significantly fewer nematodes per cm of root and per root system than the other plants. Although containing more nematodes per cm of root than C. juncea, S. indicum and D. lablab had significantly fewer nematodes per root system and per cm of root than tomato. Roots were significantly longer in the plants with the lowest nematode penetration. Although C. juncea, D. lablab, and S. indicum may have potential utility as cover or rotation crops in soil infested with M. javanica, further quantitative information on the reproduction of M. javanica and other nematodes in these plants is needed.

Evidence that both Ca(2+)-ATPase and (Ca2+ + Mg2+)-ATPase activities in the plasma membrane-rich fraction from bovine parotid gland reside on the same enzyme molecule

1. Evidence was obtained that activities of both low-affinity Ca(2+)-ATPase and high-affinity (Ca2+ + Mg2+)-ATPase in the plasma membrane-rich fraction from bovine parotid gland reside on the same enzyme. 2. Two solubilized ATPases were purified by four steps of HPLC; and both activities eluted at the same fractions from each column, and the specific activity ratio of the two enzymes at each step was constant. 3. By non-denaturing PAGE, the final preparation gave a single band for both protein staining and activity staining for the two ATPases; and the Ca(2+)-ATPase activity comigrated with that of (Ca2+ + Mg2+)-ATPase. 4. In SDS-PAGE, each activity staining for the ATPases also gave a single band, and both activities comigrated. 5. These findings suggest that Ca(2+)-ATPase and (Ca2+ + Mg2+)-ATPase are a single enzyme.

Effect of dietary nucleotide supplementation on diarrhoeal disease in infants

The effects of a nucleotide-supplemented formula on diarrhoeal disease was studied in 141 infants (group 1) who belonged to the low socioeconomic stratum; 148 controls (group 2) received the same formula but unsupplemented. Group 1 experienced less episodes of diarrhoea (109 versus 140), including less first episodes (74 versus 102; chi-square = 8.19, p < 0.004; odds ratio 2.01) and for a lesser number of days (807 versus 996 days); 45.0% and 31.1% of infants in groups 1 and 2, respectively, never developed episodes of diarrhoea. There were no differences in the clinical characteristics of the episodes or in the enteropathogens isolated from symptomatic or asymptomatic infants. The mechanisms through which nucleotides decrease the incidence of diarrhoeal disease in infants remain unclear.

Enzymatic Digestion of Roots for Recovery of Root-knot Nematode Developmental Stages

Developmental stages of Meloidogyne javanica were successfully released from roots by treatment with commercially available cellulase and pectinase. The average percentage recovery of nematode developmental stages from Dolichos lablab, Elymus glaucus, and Lycopersicon esculentum were as follows: eggs = 526%, J2 = 272%, J3 = 783%, J4 = 549%, adult females = 285%, and total = 425%, expressed as percentages of the counts obtained from stained roots spread on glass plates. Root digestion was more accurate and sensitive in detecting low numbers of nematodes in roots than was the glass plate method. No simple linear, quadratic, or cubic relationship was found between the two methods that would allow a conversion factor to be developed.

Chronic iron intake and diarrhoeal disease in infants. A field study in a less-developed country

The effect of chronic iron intake on diarrhoeal disease was evaluated in children in a community of low socio-economic stratum in Santiago, Chile. Children were incorporated into each of two consecutive cohorts; each cohort was divided into two groups, one receiving iron-enriched milk (12 mg/l) (monthly average = 70 children) and the other a control milk (1 mg/l) (monthly average = 83 children), and each cohort was followed up for 6 months. The incidence of diarrhoea was higher among the iron-supplemented children (30.4 vs 25.5 episodes/100 children/month, P < 0.025). This was mainly due to results obtained in infants 3-8 months of age during the summer months. Supplemented infants had more bowel movements on day 1 (P < 0.03) and liquid or semi-liquid stools were passed for more than 15 days more frequently (P < 0.05). While no differences were detected in aetiology, Shigella-associated episodes were less common among iron-supplemented infants (P < 0.008). Asymptomatic shedding of enteropathogens significantly increased in infants 12-18 months of age receiving iron-supplemented milk. In areas with inadequate environmental sanitation, chronic iron supplementation may have negative effects on diarrhoeal morbidity, despite improving iron nutritional status.

Field trial of an infant formula containing anti-rotavirus and anti-Escherichia coli milk antibodies from hyperimmunized cows

Two groups of 124 and 108 children, respectively, living in urban Santiago, Chile in low socioeconomic conditions were prospectively followed for 6 months for their incidence of diarrhea. Each cohort was divided into two subgroups receiving either a commercial milk formula or the same formula containing 1% (wt/wt) bovine milk immunoglobulin concentrate from cows hyperimmunized with human rotaviruses and the major enteropathogenic Escherichia coli (EPEC) serogroups. Neither group differed with respect to incidence of diarrhea (98 episodes in 117 treated children versus 95 episodes in 115 control children), duration and clinical symptoms of diarrhea, and weight gain. Furthermore, neither group differed with respect to isolation of rotavirus (14 and 13 isolates in treatment and control groups, respectively) and isolation of enteropathogenic E. coli (14 and 15 isolates in treatment and control groups, respectively). The treatment but not the control formula contained neutralizing antibody against all human rotavirus serotypes. Titers were comparable to human breast milk samples. All isolated EPEC serogroups were included in the vaccine used for the immunization of the cows. The treatment, but not the control formula, protected mice against a lethal challenge with an EPEC strain. In conclusion, feeding an antibody-supplemented formula had no positive effect on diarrheal diseases under the conditions of a fairly well-controlled small-scale field trial.

Hygiene habits and carriers in families with a child who has had typhoid fever

The relationship between asymptomatic shedding of bacterial enteropathogens and the hygiene habits of families who have had a child with typhoid fever (TF) are investigated. The sample was made up of 80 families: 40 families in which one child had had TF (Group A) and 40 in which no children or either of the parents had had a history of TF (Group B). In each group 20 families belonged to a low socioeconomic status (SES) and 20 to a high SES. A structured interview was used to evaluate the SES and the hygiene habits of the child; observations were made to measure the hygiene habits of the family (toilet, kitchen and food preparation) and bacteriological studies (fecal samples and hand markers). Results show that carriers were more frequent in Group A than in Group B. The bacterial species found were significantly more numerous in Group A than in Group B (fecal samples: E. coli, the classic serotypes, Shigella ssp, and hand markers: E. coli). Families of Group A had higher carriage rates than those of Group B. Finally there exists a significantly higher association between inadequate hygiene habits and carrier families. These results show the need to teach specific habits of proper hygiene to the entire population, because the fact of belonging to the high SES does not in itself preclude inadequate hygiene habits.

Liquid and protein dynamics using a new minimally invasive pleural catheter in rabbits

To obtain continuous access to the pleural space without causing injury, we tested a new transdiaphragmatic pleural catheter for its ability 1) to drain the pleural space without injury and 2) to drain liquid at a rate equal to normal pleural liquid production. In 13 anesthetized rabbits, we opened the abdomen and dissected through the diaphragm to insert a flared-tip catheter into the ventral pleural space on one side and then turned the rabbit prone. In 10 of the rabbits (8 for 6 h, 2 for 24 h), we continuously collected draining pleural liquid, and in 3 rabbits (6 h), we did not open the catheter. We injected radiolabeled albumin intravenously as a protein marker. Terminally, we collected pleural liquid from both pleural spaces and lavaged for total radioactivity. In 14 awake control rabbits without catheters, we measured normal pleural liquid production by the rate of equilibration of radiolabeled albumin from plasma to pleural liquid. We found that, although the percentage of neutrophils was increased on the side with the catheter (54 vs. 1% in control rabbits), the pleural liquid volume, protein concentration, specific activity of albumin, and total radioactivity in the pleural space were the same on the side with the catheter as on the opposite side and in the control rabbits. The liquid flow rate through the catheter over 6 h was 53 +/- 23 microliters/h [0.017 +/- 0.008 (SD) ml.kg-1.h-1], which was not significantly different from the computed rate of normal pleural liquid production in the control rabbits, 49 +/- 14 microliters/h (0.016 +/- 0.004 ml.kg-1.h-1).(ABSTRACT TRUNCATED AT 250 WORDS)

[Application of a model for predicting morbidity in children from a low socioeconomic level]

An instrument to be used at a primary health care level was built on the basis of a predictive model for diarrhea obtained during a previous study. The instrument was applied to 720 mothers or caregivers of infants living in the Southeastern area of Santiago. 83 infants who fulfilled the requisites of the instrument were surveyed during July-August 1989 and compared to age, nutritional and socioeconomic status matched children not fulfilling the same requisites. Infants selected by the predictive instrument suffered 4 times more morbid episodes and respiratory infections and 5 times more diarrheal episodes than controls. Symptoms were present in them during 50% of the survey period as opposed to 14% in controls. Mothers of children at risk had inadequate behaviors in respect to health care of their children and did not follow many of the National Health programs available for their families. The predictive instrument tested may be useful to identify children at high risk of morbidity, creating the possibility for special interventions in them.

Persistent diarrhoea in the community. Characteristics and risk factors

In 58 previously well-nourished patients who were fed cow's milk and who later developed persistent diarrhoea (greater than or equal to 15 days), data obtained during the first 8 days of acute diarrhoea were compared with those of patients whose episodes lasted less than or equal to 8 days. Children with persistent diarrhoea weighted less at birth, passed greater than or equal to 6 stools/day during the first 48 hours, received early treatment with antibiotics. Their milk feedings were stopped during the first 48 hours, they had a past history of digestive diseases and hospitalizations, they were brought in for consultation after 5 days of symptoms and their nutritional status deteriorated more (p less than 0.003, p less than 0.03, p less than 0.0001, p less than 0.0001, p less than 0.0001, p less than 0.002, p less than 0.0001, and p less than 0.03, respectively). Their mothers were significantly younger (p less than 0.0013), had better schooling (p less than 0.037), and fewer children (p less than 0.044), and were separated from the index child during the day more often (p less than 0.056). After persistent diarrhoea was diagnosed, enteropathogens in stools or lactose intolerance or both were demonstrated in 75.9%. Treatment induced remission in all cases. Using logistic regression a predictive model was established which enables us to identify, among patients with acute diarrhoea, those at risk of prolonging their illness.

Developmental changes in pleural liquid protein concentration in sheep

The source of normal pleural liquid is thought to be the systemic circulation of the pleural membranes rather than the pulmonary circulation of the nearby lung. Evidence for a systemic origin comes from the low protein concentration of pleural liquid in adult sheep, which is consistent with protein sieving from a high-pressure circulation. During normal development from fetal to adult life, systemic vascular pressure increases. We therefore reasoned that if pleural liquid comes from the systemic circulation, pleural liquid protein concentration relative to plasma protein concentration should decrease during normal development. To test this hypothesis we did thoracotomies on 14 fetal, 9 newborn, and 15 adult sheep and collected pleural liquid and plasma for measurement of total protein and albumin concentrations. In separate experiments we measured steady-state systemic and pulmonary vascular pressures in age-matched chronically instrumented fetal, newborn, and adult sheep. The protein concentration in pleural liquid relative to that in plasma (pleural liquid/plasma) decreased progressively with age (fetuses, 0.50 +/- 0.15 [SD]; newborns, 0.27 +/- 0.08; adult, 0.15 +/- 0.05); the trend was similar for pleural liquid/plasma albumin ratios as a function of age. Systemic arterial pressure increased progressively during development, whereas pulmonary arterial pressure decreased from the fetus to the adult sheep. These observations support the hypothesis that normal pleural liquid originates from a systemic circulation.

[Cryptosporidiosis: studies in children in communities of low socioeconomic level]

Cryptosporidium was detected in 2 (1.5%) out of 132 children under 2 years with acute diarrhea; in 2 (3.2%) out of 63 patients under 2 years with persistent diarrhea; in 1 (3.9%) out of 26 malnourished patients younger than 2 years with an episode of acute diarrhea and in 7 (1.4%) out of 516 pediatric ambulatory patients who consulted for acute or chronic diarrhea or recurrent abdominal pain. The clinical histories of the 5 infants with cryptosporidiosis who belonged to the first 3 studies, are presented. All they had prolonged diarrhea (more than 15 days long), and one of them showed low IgG and IgA serum concentrations, but normal proportions of T lymphocyte populations.

Typhoid fever in children of low and high socioeconomic strata: comparison of hygiene habits

The relationship between the hygienic habits of children who had typhoid fever (TF) who had recently begun attending school and their family group, is assessed. It is supposed that children, independently of their SES, acquired TF because of inadequate habits which facilitated the oral-fecal cycle. The sample was formed of 40 child-mother dyads: 20 of low SES (group A) and 20 of high SES (group B), the child of each of which had had TF. Results showed that the hygienic habits of children with respect to the oral-fecal cycle, their perception of school toilet cleanliness as well as the mothers' explanation of their children's hygienic habits is very similar in the two groups. The importance of these results is that the SES is seem to be irrelevant in the case of TF but that the hygienic habits of the children are of importance. Public health policy should be modified to include the teaching of proper hygienic habits (oral-fecal cycle).

[Trial of milk with low-lactose contents in acute diarrhea]

Fifty infants with acute diarrhea (less than or equal to 5 days of duration) were refed with either a low-lactose formula (experimental group, N = 25) or whole powdered cow's milk (control group, N = 25). During a two-month follow up etiology, clinical course, changes of anthropometric parameters and tolerance to the milk products were evaluated. The etiology of diarrhoea, the mean duration of the episodes (3.6 +/- 1.9 and 3.9 +/- 1.9 days in the experimental and control group, respectively) and the clinical course were comparable in both groups. Nutritional parameters remained unchanged during and after the episode. In two children (8.3%) of the control group stools continued to be liquid, fecal pH was 5 and reducing substances were positive. They had to be refed with the low-lactose product to induce remission of the symptoms. Both products were well tolerated. These findings suggest that availability of low-lactose formulae may be advantageous in the clinical management of infants with acute diarrhea and evidence of lactose intolerance.

[Modular diet and parenteral support in persistent diarrhea]

Eleven infants with protracted diarrhea were treated with modular diet and short-term parenteral nutrition. Mean age at admission was 3.7 months with males predominating. Enteropathogenic E. coli, classic serotypes, were isolated from 7 patients and rotavirus from one. A child with combined, severe immunodeficiency died. Milk protein intolerance was diagnosed in another patient. Balance studies and peroral biopsies were performed. Malnutrition was more frequent and hospital stay was longer in those infants who developed nosocomial infections. Even though this treatment shortened the duration of the hospitalization, the negative nutritional impact persisted: Weight/Age (NCHS) decreased from 84% to 61%, with rapid recovery after discharge. Fecal lactic acid excretion was increased on admission to 1,296 mg x day and disaccharidase activity was decreased. The modular diet decreased both fecal volume and lactic acid excretion.

Effect of an acidified milk on diarrhoea and the carrier state in infants of low socio-economic stratum

The effect on diarrhoeal disease of an acidified, modified powdered cow's milk infant formula (Pelargon) was evaluated in 82 infants (Group I) for six months; 104 infants who received the same formula but non acidified, served as controls (Group II). Nutritional status remained satisfactory in both groups throughout the observation period. Some children rejected the taste of the acidified milk. The incidence of diarrhoea was lower in Group I (p less than 0.001). The proportion of days in which the children suffered from acute diarrhoea, and the duration of the episodes were also lower in the children given the acidified milk (p less than 0.001). The rate of detection of enteropathogens and the species identified were comparable in both groups. Carrier rates for bacterial enteropathogens fell over time in Group I while they rose in Group II (p less than 0.001). Carrier rates for enteric parasites were comparable to those expected in our setting for this age group. These results suggest that acidified milk exerts a protective effect against diarrhoeal disease.

[Retrospective evaluation of persistent diarrhea at a primary health service]

Information about persistent diarrhea is scarse despite the fact that it is a frequent cause of death in children who live in developing countries. The 36,358 pediatric consultations performed at a Primary Health Care Center in Southeastern Santiago in 1984 were retrospectively evaluated. Diarrheic syndromes represented 5.1% of consultations and corresponded to 909 episodes; of these, 6.3% were cases of persistent diarrhea (greater than 15 days). The highest frequency occurred among children under 2 years of age (60.7%). In 68.7% of cases feces were liquid and in 37.5% mucus, pus or blood was present in stools. Persistent diarrhea was more frequent among malnourished patients (p less than 0.001) who, in turn, suffered the greatest nutritional deterioration in relation to the episode of diarrhea. Intravenous fluids were required by 23.3% of patients while 27.9% were admitted to hospital. This contrasts with patients who suffer episodes which lasted less than 15 days, who were all orally hydrated and only 7.8% required hospitalization (p less than 0.01).

Faecal excretion of rotavirus and other enteropathogens in newborns of the high and low socio-economic stratum in Santiago, Chile

Faecal excretion of enteropathogens was studied in newborns in their first week of life. Rotavirus was investigated in 225 neonates, of whom 107 belonged to the low socio-economic stratum (SES) and 118 to the high SES. Half of each group were delivered by caesarean section. Rotavirus was detected in 10 infants (4.4%). Eight of them had been in the same ward and excreted the same viral electrophoretype. Enteropathogenic bacteria were isolated from 8 out of 57 (14.0%) newborns. Positive cultures were equally distributed by SES and route of delivery. Giardia lamblia was the only parasite detected, in one infant (2.6%) of the high SES. None of the children developed symptoms. Faecal excretion of enteropathogens ended spontaneously within a week in all cases. It is suggested that the lack of symptomatology and the spontaneous termination of the faecal excretion are related to immaturity of the small intestinal mucosa, that does not allow the completion of the steps that must take place during a successful infectious event.

Effect of structured dietary fiber on bioavailability of amoxicillin

The effect of structured dietary fiber on the bioavailability of amoxicillin (AMX) was evaluated. Ten healthy volunteers ingested one of two isocaloric, isonitrogenous diets providing 7.8 gm/day (diet I) and 36.2 gm/day (diet II) of structured fiber for 3 days. Then they ingested one tablet (500 mg) AMX after breakfast. The other diet was administered for an additional 3 days and the study was repeated. Plasma and urinary AMX concentrations were measured at 9 and 24 hours, respectively, by a microbiologic technique. An open one-compartment model was used for pharmacokinetic analysis. AMX was absorbed more slowly when ingested with diet I than with diet II: the absorption rate constant was 1.04 +/- 0.37 and 1.75 +/- 0.75 (P less than 0.05); lag time for absorption was 0.34 +/- 0.13 hours and 0.29 +/- 0.11 hours (P less than 0.05). The first-order rate constant and elimination half-life were similar. Bioavailability was higher with diet I: the AUC was 12.17 +/- 3.04 vs. 9.65 +/- 2.64 micrograms/ml/hr with diet II (P less than 0.05). A higher content of dietary fiber increased AMX absorption rate and decreased the amount of drug absorbed.

Chronic environmental enteropathy in a temperate climate

Forty-three apparently healthy young adult male volunteers underwent an evaluation of their nutritional status, blood chemistry and faecal excretion of enteropathogens, which did not reveal current malnutrition or illnesses. Ten of them were further studied for small intestinal histology, culture of aerobic and anaerobic bacteria in the duodenal juice, disaccharidase activities, glucose absorption and faecal excretion of fat and nitrogen. The study revealed mild morphological changes associated with the appearance of anaerobic bacteria in the upper intestine, decreased glucose transport and increased faecal losses of nitrogen. Although all these changes were rather mild, they may be significant for people whose diet is of borderline nutritional quality.

Acute diarrhoea and asymptomatic infection in Chilean preschoolers of low and high socio-economic strata

Preschoolers who belonged to the high (Group I, n = 112) or the low (Group II, n = 90) socio-economic stratum were followed prospectively for six months. Mean monthly incidence of diarrhoea was 3 and 7 episodes per 100 children for Group I and Group II respectively (p less than 0.001). Episodes were shorter and affected a smaller proportion of children in Group I (p less than 0.002 and p less than 0.05), respectively). Bacterial enteropathogens were recovered in 12.6% and 13.5% of the episodes in Group I and Group II and parasites in 15.4% and 62.8%, respectively. Rotavirus was detected once in each group. Asymptomatic carrier rates for enteropathogenic bacteria were 12.0% in Group I and 7.2% in Group II. The corresponding figures for parasites were 28.2% and 62.8% (p less than 0.001). Nutritional status was normal in all children. These results suggest that socio-economic stratum plays an important role in the characteristics of diarrhoeal illness in the groups which conform the population of the less developed countries. Acute diarrhoea is less frequent in preschoolers living in Santiago than in other developing areas. Rates of asymptomatic infection are high.

Enteropathogens associated with acute diarrhea in hospitalized infants

Thirty-five infants of low socioeconomic status who were living in urban Santiago were hospitalized for acute diarrhea were prospectively evaluated for the presence of enteropathogens associated with the episode. Some degree of malnutrition was evident in 20 infants (57.1%); 15 of these (75%) were under 6 months of age. Mean duration of the hospital stay was 11.8 days for well-nourished patients and 15.7 days for the malnourished patients. One or more enteropathogens were found in 60% of the cases studied: in 17 cases (48.6%) these were bacteria and in four cases (11.4%) it was rotavirus. Parasites were not detected. In three patients, two different pathogens were demonstrated. Among the bacteria, 12 isolates (34.3%) were enteropathogenic E. coli (EPEC) and two (5.7%) were Shigella. Campylobacter jejuni was also isolated from two different cases (5.7%) and Salmonella from one case (2.9%). The recovery of pathogens was independent of the nutritional status. Mean age of detection of EPEC was 3.2 months among well-nourished infants and 6.2 months among the malnourished (p less than 0.001). Half of the EPEC strains isolated were multiresistant to antibiotics. One of these strains transferred some of its resistance in vitro to E. coli K12. Ampicillin and kanamycin were the antibiotics to which EPEC showed the greatest resistance. The other bacterial pathogens were mostly sensitive to antibiotics. Campylobacter jejuni, together with Shigella, was the second most frequent pathogen isolated during episodes of diarrhea. Campylobacter should be included in the routine study of diarrheal episodes in our setting.

Acute diarrhoeal disease in children under 7 years of age in a peri-urban slum of Santiago, Chile

A group of 168 families who lived in a peri-urban slum in Santiago were surveyed for 9 months. All of them had a child under 7 years of age. Medical activities and data collection were carried out at a Field Station and by means of twice-weekly visits to each home, at which time cases of diarrhoea were recorded and investigated. Faecal samples for bacteriological, parasitological and rotavirus studies were obtained during each episode. The characteristics of clinical course, hygienic practices in the family, and monthly anthropometric measurements of infants and toddlers were also recorded. The mean monthly incidence of diarrhoea was 7.1 episodes per 100 children. Of the episodes, 44.2% were associated with pathogenic bacteria, 14.4% with rotavirus, 38.4% with parasites and in 27.9% no enteropathogens were identified. It was found that adequate hygienic habits were not associated with a decreased risk of developing diarrhoea and that about 60% of children did not have diarrhoea throughout the study period. The nutritional status was adequate in most cases: weight-for-age was below the 5th percentile in 11.5% of subjects and the height-for-age was normal in all. No moderate or severe cases of malnutrition were detected.