Relationship between exposure to parabens and benzophenones and prostate cancer risk in the EPIC-Spain cohort

The etiology of prostate cancer is not fully elucidated. Among environmental risk factors, endocrine-disrupting chemicals (EDCs) deserve special mention, as they alter metabolic pathways involved in hormone-dependent cancers. Epidemiological evidence assessing the carcinogenicity of EDCs is scarce. The aim of this study was to analyze the relationship between exposure to parabens and benzophenones and prostate cancer risk. We conducted a case-cohort study nested within the EPIC-Spain prospective multi-center cohort. Study population comprised 1,838 sub-cohort participants and 467 non-sub-cohort prostate cancer cases. Serum concentrations of four parabens and two benzophenones were assessed at recruitment. Covariates included age, physical activity, tobacco smoking, alcohol consumption, body mass index, educational level and diabetes. Borgan II weighted Cox proportional hazard models stratified by study center were applied. Median follow-up time was 18.6 years (range = 1.0-21.7 years). Most sub-cohort participants reached primary education at most (65.5%), were overweight (57.7%) and had a low level of physical activity (51.3%). Detection percentages varied widely, being lowest for butyl-paraben (11.3%) and highest for methyl-paraben (80.7%), which also showed the highest geometric mean (0.95 ng/ml). Cases showed significantly higher concentrations of methyl-paraben (p = 0.041) and propyl-paraben (p < 0.001). In the multivariable analysis, methyl-paraben - log-transformed (HR = 1.07; 95%CI = 1.01-1.12) and categorized into tertiles (HR = 1.60 for T3; 95%CI = 1.16-2.20) -, butyl-paraben - linear (HR = 1.19; 95%CI = 1.14-1.23) and log-transformed (HR = 1.17; 95%CI = 1.01-1.35) - and total parabens - log-transformed (HR = 1.09; 95%CI = 1.02-1.17) and categorized into tertiles (HR = 1.62 for T3; 95%CI = 1.10-2.40) - were associated with an increased prostate cancer risk. In this study, higher concentrations of methyl-, butyl-, and total parabens were positively associated with prostate cancer risk. Further research is warranted to confirm these findings.

Teaching hospitals and their influence on survival after valve replacement procedures: A retrospective cohort study using inverse probability of treatment weighting (IPTW)

BACKGROUND

The effect of teaching hospital status on cardiovascular surgery has been of common interest in recent decades, yet its magnitude on heart valve replacement is still a matter of debate. Given the ethical and practical unfeasibility of randomly assigning a patient to such an exposure, we use the inverse probability of treatment weighting (IPTW) to assess this marginal effect on the survival of Colombian patients who underwent a first heart valve replacement between 2016 and 2019.

METHODS

A retrospective cohort study was conducted based on administrative records. The time-to-death event and cumulative incidences of death, readmission, and reoperation are presented as outcomes. An artificial sample is configured through IPTW, adjusting for sociodemographic variables, comorbidities, technique, and intervention weight.

RESULTS

Of a sample of 3,517 patients, 1,051 (29.9%) were operated on in a teaching hospital. The median age was 65.0 (18.1-91.5), 38.5% of patients were ≤60, and 6.9% were ≥80. The cumulative incidences of death at 30, 90 days, and one year were 5.9%, 8%, and 10.9%, respectively. Furthermore, 23.5% of the patients were readmitted within 90 days and 3.6% underwent reintervention within one year. The odds of 30-day mortality are lower for patients operated in a teaching hospital (OR 0.51; 95% CI 0.29-0.92); however, no effect on survival was identified in terms of time-to-event of death (HR 1.07; 95%CI 0.78-1.46).

CONCLUSIONS

After IPTW, the odds of 30-day mortality are lower for patients operated in a teaching hospital. There was no effect on survival, 90-day or one-year mortality, 90-day readmission, or one-year reintervention. Together, we offer an opening for investigating an exposure that has yet to be explored in Latin America with potential value to understand teaching hospitals as the essential nature of reality of an academic-clinical synergy.

Can Wolf Spider Mothers Detect Insecticides in the Environment? Does the Silk of the Egg-Sac Protect Juveniles from Insecticides?

The use of pesticides for plague control in agroecosystems generates a threat to wildlife and a major problem for human health. Pesticide compounds are also an important source of water and atmosphere contamination. Although insecticides are effective on their target organisms, they often affect organisms that are not their target. The aim of the present study was to research the effects of 3 types of neurotoxic insecticides-a pyrethroid (cypermethrin), a neonicotinoid (imidacloprid), and an organophosphate (chlorpyrifos)-on behavioral and physiological parameters of Pardosa saltans spider (Lycosidae). Our study analyzed for the first time the exploratory behavior of the spider mothers in the presence of these 3 insecticides on their egg-sacs and also on the ground. We also evaluated the oxidative stress effects on the juveniles hatched in the egg-sac protected by silk in relation to variations in detoxification enzymes (catalase, glutathione reductase, superoxide dismutase, glutathione-S-transferase, and glutathione peroxidase) and lipid peroxidation (reactive oxygen species [ROS]). The results show that these insecticides are repellents for mothers (cypermethrin is the most repellent), and maternal behavior is modified after detection of an insecticide on their egg-sac but mothers do not abandon their egg-sacs. These neurotoxic insecticides affect the juveniles inside their egg-sac. Cypermethrin and chlorpyrifos caused more oxidative stress in juveniles than did imidacloprid. The ROS generated by these insecticides seemed to be adequately eliminated by the juveniles' antioxidant systems. Environ Toxicol Chem 2021;40:2861-2873. © 2021 SETAC.

Electrical Power Diversification: An Approach Based on the Method of Maximum Entropy in the Mean

Electrical energy is generated in different ways, each located at some specific geographical area, and with different impact on the environment. Different sectors require heterogeneous rates of energy delivery, due to economic requirements. An important problem to solve is to determine how much energy must be sent from each supplier to satisfy each demand. Besides, the energy distribution process may have to satisfy ecological, technological, or economic cost constraints.

HyRA: A Hybrid Recommendation Algorithm Focused on Smart POI. Ceutí as a Study Scenario

Nowadays, Physical Web together with the increase in the use of mobile devices, Global Positioning System (GPS), and Social Networking Sites (SNS) have caused users to share enriched information on the Web such as their tourist experiences. Therefore, an area that has been significantly improved by using the contextual information provided by these technologies is tourism. In this way, the main goals of this work are to propose and develop an algorithm focused on the recommendation of Smart Point of Interaction (Smart POI) for a specific user according to his/her preferences and the Smart POIs’ context. Hence, a novel Hybrid Recommendation Algorithm (HyRA) is presented by incorporating an aggregation operator into the user-based Collaborative Filtering (CF) algorithm as well as including the Smart POIs’ categories and geographical information. For the experimental phase, two real-world datasets have been collected and preprocessed. In addition, one Smart POIs’ categories dataset was built. As a result, a dataset composed of 16 Smart POIs, another constituted by the explicit preferences of 200 respondents, and the last dataset integrated by 13 Smart POIs’ categories are provided. The experimental results show that the recommendations suggested by HyRA are promising.

Celiac disease associated antibodies in persons with latent autoimmune diabetes of adult and type 2 diabetes

BACKGROUND

Celiac Disease (CD) is present in 1-16.4% of patients with type 1 diabetes mellitus. The most important serological markers of CD are anti-endomysial (EMA), anti-tissue transglutaminase (tTGA) and antigliadin antibodies (AGA).

AIM/HYPOTHESIS

The objective of this work is to determine the frequency of tTGA and/or AGA in latent autoimmune diabetes of adult (LADA) and subjects with type 2 diabetes (T2DM), as well as to evaluate their relation with several clinical and biochemical characteristics.

SUBJECTS AND METHODS

Forty three subjects with LADA and 99 with T2DM were studied. The presence of AGA, tTGA was determined in the sera of these patients. The variables: sex, age, duration of diabetes, treatment, body mass index (BMI) and fasting blood glucose concentration were also recorded.

RESULTS

No differences were found in the frequency of celiac disease associated antibodies between LADA and T2DM subjects. The presence of celiac disease related antibodies was more frequent in patients with a normal or low BMI.

CONCLUSIONS

Celiac disease does not seem to be related with pancreatic autoimmunity in type 2 diabetes. Celiac disease causes a decrease of body mass index in type 2 diabetes while pancreatic islet autoimmunity in this entity masks this effect.

Inequalities in access to education and healthcare

The burden of disease is borne by those who suffer as patients but also by society at large, including health service providers. That burden is felt most severely in parts of the world where there is no infrastructure, or foreseeable prospects of any, to change the status quo without external support. Poverty, disease and inequality pervade all the activities of daily living in low-income regions and are inextricably linked. External interventions may not be the most appropriate way to impact on this positively in all circumstances, but targeted programmes to build social capital, within and by countries, are more likely to be sustainable. By these means, basic oral healthcare, underpinned by the primary healthcare approach, can be delivered to more equitably address needs and demands. Education is fundamental to building knowledge-based economies but is often lacking in such regions even at primary and secondary level. Provision of private education at tertiary level may also introduce its own inequities. Access to distance learning and community-based practice opens opportunities and is more likely to encourage graduates to work in similar areas. Recruitment of faculty from minority groups provides role models for students from similar backgrounds but all faculty staff must be involved in supporting and mentoring students from marginalized groups to ensure their retention. The developed world has to act responsibly in two crucial areas: first, not to exacerbate the shortage of skilled educators and healthcare workers in emerging economies by recruiting their staff; second, they must offer educational opportunities at an economic rate. Governments need to lead on developing initiatives to attract, support and retain a competent workforce.

Variações anatômicas do ramo tenar do nervo mediano no túnel do carpo

Lanz, em 1977, classificou as possíveis variações do ramo motor no nervo mediano em relação ao ligamento transverso do carpo. Baseado nesse trabalho, foi proposto um estudo realizado em cadáveres para observar as possíveis variações da anatomia do ramo motor do nervo mediano. Foram utilizadas 44 peças anatômicas de membros superiores conservadas em formol. Foram dissecadas, cuidadosamente, a emergência e a entrada do ramo tenar na musuclatura, observando o número de ramos, a região da emergência e o tipo de trajeto, de acordo com a classificação de Lanz. A variação mais encontrada foi a anormalidades no trajeto do ramo tenar do nervo mediano, sendo a maior parte do tipo extra-ligamentar. A maior parte das peças anatômicas possuía apenas um ramo tenar do nervo mediano.

Type 1 diabetes islet associated antibodies in subjects infected by echovirus 16

AIMS/HYPOTHESIS

To determine whether the emergent infection by echovirus 16 that occurred in Cuba during the year 2000 was related to the presence of Type 1 diabetes associated autoantibodies.

METHODS

The presence of ICA, IAA, GADA, IA2 antibodies and neutralizing antibodies (NtAb) to echovirus 16 were determined in sera from 38 infected children and adolescents and 80 control subjects, matched in sex, age, local residence and time of sample collection.

RESULTS

The occurrence of a large-scale echovirus 16 epidemic was associated with the appearance of humoral autoimmune markers of Type 1 diabetes, especially for ICA, IAA and GADA. In the convalescent stage, ICA, IAA and GADA seroconversion was shown in 92.1%, 44.7% and 28.9% of echovirus 16 infected subjects. None of the 80 uninfected subjects had ICA or IAA, while one was GADA positive. ICA, IAA and GADA frequency was higher in the convalescent than in the acute stage (p<0.0005). A strong positive correlation was found between the NtAb to echovirus 16 and ICA titres in both acute and convalescent stage (r=0.91; p<0.0001, r=0.55; p=0.0003 respectively).

CONCLUSION/INTERPRETATION

This work provides evidence of an association between echovirus 16 infection and the presence of Type 1 diabetes related antibodies (ICA, IAA and GADA). Our data show that the echovirus 16 infection might be capable of inducing a process of autoimmune beta-cell damage and support the hypothesis that enterovirus infections are important risk factors for the development of Type 1 diabetes.

Echovirus 4 and type 1 diabetes mellitus

AIMS/HYPOTHESIS

To determine the association between exposure to enteroviruses and Type 1 diabetes.

METHODS

We measured neutralizing antibodies to the following enteroviruses: Coxsackievirus CA9, CB1, CB2, CB3, CB4, CB5, CB6, and Echovirus E4, E6, E9, E11 in the sera of (1) Type 1 diabetic patients at diagnosis (n = 33), (2) healthy offspring of parents with Type 1 diabetes without islet cell antibodies (ICA) (n = 43) and (3) normal controls (n = 57). All subjects were less than 20 years old. We performed the neutralization test determining the cytopathogenic effect on Vero cells. HLA DR serotyping was also performed in Group 2.

RESULTS

Type 1 diabetic patients showed a higher frequency (21.2%, p < 0.01) of neutralizing antibodies to E4 in relation to controls (1.8%), although there were no differences comparing with offspring of Type 1 diabetic patients (20.9%). Healthy offspring carrying Type 1 diabetes HLA DR susceptibility genes were also exposed to E4 (15.0%). High frequencies of neutralizing antibodies to most enteroviruses were found in the control group.

CONCLUSION

This study shows the association between Type 1 diabetes and the presence of neutralizing antibodies to Echovirus 4, suggesting the possible participation of this virus as an environmental trigger of this autoimmune disease. Interestingly, our population displays high frequencies of exposure to enterovirus (including CB4) although the incidence for Type 1 diabetes is low (2.9 per 100,000 inhabitants).

Diagnosis of superficial esophageal cancer and dysplasia using endoscopic screening with a 2% lugol dye solution in patients with head and neck cancer

BACKGROUND

Head and neck cancer (HNC) has a high incidence in Brazil, with cancer of the oral cavity being one of the five most common cancers among Brazilians. Alcohol and tobacco consumption may contribute to synchronous or metachronous HNC and esophageal cancer. The early detection of superficial esophageal cancer and dysplasia in asymptomatic patients with HNC, after successfully treating the primary cancer, may provide an effective cure.

METHODS

A prospective study involving 60 patients with HNC was carried out at the State University of Campinas (UNICAMP) to screen for superficial esophageal cancer and dysplasia using endoscopy and a 2% lugol dye solution followed by biopsy of the suspicious areas.

RESULTS

Five patients (8.3%) had superficial esophageal cancer, which was diagnosed as intraepithelial carcinoma in three of them (5.0%). In four patients, the superficial esophageal cancer was synchronous, and in one it was metachronous to HNC. Five patients (8.3%) had dysplasias in the esophageal epithelium (three were classified as mild and two as moderate).

CONCLUSION

These results demonstrate the value of endoscopic screening of the esophagus using lugol dye in patients with HNC, particularly because superficial esophageal cancer is extremely difficult to detect by conventional methods in asymptomatic patients.

Diagnosis of superficial esophageal cancer and dysplasia using endoscopic screening with a 2% lugol dye solution in patients with head and neck cancer

BACKGROUND

Head and neck cancer (HNC) has a high incidence in Brazil, with cancer of the oral cavity being one of the five most common cancers among Brazilians. Alcohol and tobacco consumption may contribute to synchronous or metachronous HNC and esophageal cancer. The early detection of superficial esophageal cancer and dysplasia in asymptomatic patients with HNC, after successfully treating the primary cancer, may provide an effective cure.

METHODS

A prospective study involving 60 patients with HNC was carried out at the State University of Campinas (UNICAMP) to screen for superficial esophageal cancer and dysplasia using endoscopy and a 2% lugol dye solution followed by biopsy of the suspicious areas.

RESULTS

Five patients (8.3%) had superficial esophageal cancer, which was diagnosed as intraepithelial carcinoma in three of them (5.0%). In four patients, the superficial esophageal cancer was synchronous, and in one it was metachronous to HNC. Five patients (8.3%) had dysplasias in the esophageal epithelium (three were classified as mild and two as moderate).

CONCLUSION

These results demonstrate the value of endoscopic screening of the esophagus using lugol dye in patients with HNC, particularly because superficial esophageal cancer is extremely difficult to detect by conventional methods in asymptomatic patients.

Diagnosis of superficial esophageal cancer and dysplasia using endoscopic screening with a 2% lugol dye solution in patients with head and neck cancer

BACKGROUND

Head and neck cancer (HNC) has a high incidence in Brazil, with cancer of the oral cavity being one of the five most common cancers among Brazilians. Alcohol and tobacco consumption may contribute to synchronous or metachronous HNC and esophageal cancer. The early detection of superficial esophageal cancer and dysplasia in asymptomatic patients with HNC, after successfully treating the primary cancer, may provide an effective cure.

METHODS

A prospective study involving 60 patients with HNC was carried out at the State University of Campinas (UNICAMP) to screen for superficial esophageal cancer and dysplasia using endoscopy and a 2% lugol dye solution followed by biopsy of the suspicious areas.

RESULTS

Five patients (8.3%) had superficial esophageal cancer, which was diagnosed as intraepithelial carcinoma in three of them (5.0%). In four patients, the superficial esophageal cancer was synchronous, and in one it was metachronous to HNC. Five patients (8.3%) had dysplasias in the esophageal epithelium (three were classified as mild and two as moderate).

CONCLUSION

These results demonstrate the value of endoscopic screening of the esophagus using lugol dye in patients with HNC, particularly because superficial esophageal cancer is extremely difficult to detect by conventional methods in asymptomatic patients.

Parapharyngeal space tumors: considerations in 26 cases

CONTEXT

Parapharyngeal space tumors comprise less than 0.5% of all head and neck neoplasms. The majority of these tumors are benign, but surgery is usually required to establish the diagnosis and treat the patients. We present 26 patients treated surgically for tumors arising in the parapharyngeal space (PPS) at the State University of Campinas Hospital--UNICAMP.

CASES SERIES

Of these, 17 (65.5%) had benign and 9 (34.6%) malignant neoplasms. The surgical and pathological data relevant to these cases are highlighted, observing any local recurrence, surgical complications and the five-year survival. Neurogenic tumors and soft tissue sarcomas were, respectively, the most frequent benign (35.3%) and malignant neoplasms (44.5%). Benign tumors accounted for the majority of the cases and involved minimal surgical morbidity with no recurrence during a median follow-up of five years. Malignant tumors had a high rate of recurrence and mortality. Surgery is the treatment of choice for PPS tumors. A knowledge of the anatomy of this site is essential for the safe performance of surgical procedures. Malignant neoplasms have a poor prognosis. Fine needle aspiration was helpful in diagnosis of all tumors.

[Cryosurgery of liver neoplasms]

Cryosurgery is the in situ destruction of tissue using subzero temperatures. Its use for the treatment of some unresectable liver tumors has been clearly established as a therapeutic option. Experimental studies have demonstrated the feasibility of freezing of large liver volumes without any major metabolic and hemorrhagic complications. Modern cryosurgery has received substantial impetus from the development of automated cryosurgical apparatuses using liquid nitrogen. Intraoperative ultrasound has enhanced the process by enabling visualization of tissue freezing and ensuring precise and optimal treatment of the tumor. Clinical reports of cryosurgery for liver primary tumors and metastases have confirmed the safety of the procedure. Major complications include myoglobinuria, coagulopathy and pleural effusions. The benefit of cryosurgery is that it broadens the number of patients that can be brought to surgery and can potentially become disease-free.

Changes in dopamine and acetylcholine release in the rat lateral hypothalamus during deprivation-induced drinking

Neurochemical changes in the rat lateral hypothalamus during drinking were assessed in 20 min sampling intervals, using in vivo brain microdialysis. Water-deprived animals drank (11 +/- 1 ml) during the hour that water was available. Drinking was maximal (7.8 +/- 0.7 ml) during the first 20 min after water presentation and minimal during the last 20 min (0.5 +/- 0.4 ml). There was a local enhancement in DA turnover evidenced by an increase in the extracellular levels of dopamine (DA) (155 +/- 47% during the second sample after water presentation as compared to predrinking levels) and dihydroxyphenyl acetic acid (DOPAC) (132 +/- 9.7% in the sample that followed water removal). There was also an initial increase in the acetylcholine (ACh) release (145.1 +/- 21.7%) during the first 20 min after water presentation followed by a reduction (50.12 +/- 18%) 20 min later. These changes are congruous with previously published results suggesting that both neurochemical systems are involved in the regulation of water intake. Considering that the exogenous administration of cholinergic drugs in this hypothalamic area elicits drinking, the initial increase in ACh release could be interpreted as one of the neurochemical events driving this behavior. Since the local blockade of D2 receptors has been shown to result in drinking the progressive increase in DA turnover detected in this study, as well as the concomitant reduction in ACh release, could be involved in drinking attenuation.

[Transvaginal echographic evaluation of myometrial invasion in patients with endometrial cancer]

Twenty-one patients with endometrial cancer who underwent laparotomy, were pre-operatively examined by transvaginal sonography. A deep myometrial invasion (> 50%) was noted sonographically in 9 patients (42.3%), with a superficial invasion (< 50%) in 12 (57.2%). A deep invasion was histologically seen in 10 patients (47.6%), with a superficial invasion in 11 (52.4%). In myometrial deep invasion evaluation, transvaginal sonography showed a 90% sensibility, a 73% specificity, a 75% positive predictive value and a 93% negative predictive value. In 3 cases (14.3%) the invasion depth was sonographically overestimated and in 1 case (4.8%) underestimated. These results make possible an important role of transvaginal sonography in staging endometrial cancer, to select patients needing for pelvic and lomboaortic lymphadenectomy over total abdominal hysterectomy with vaginal collar.

Hepatic cryosurgery precision: evaluation of ultrasonography, thermometry, and impedancemetry in a pig model

One of the main problems of the use of liver cryosurgery is to be sure that a defined hepatic volume has been completely destroyed. We undertook an experimental pig study to determine histopathological evolution of cryolesions, to evaluate the value of intraoperative sonography, thermometry, and impedancemetry to monitor necrosis and to evaluate clinical and biological repercussions of hepatic cryosurgery. Forty-eight cryolesions were obtained by freezing each liver lobe of 12 experimental pigs during a 5-min contact with a flat cryoprobe cooled with liquid nitrogen. Cryolesions and the surrounding liver were monitored during cryosurgery by six thermocouple electrodes, five impedance electrodes, and intraoperative sonography. Animals were sacrificed immediately, 6 hr and between day 1 and day 32 after the procedure. Cryolesions were excised, and a full size pathological study was carried out. No morbidity or mortality was observed. At the end of the freezing time, cryolesions were hemispheric in shape, and their radius measured by sonography was 17.7 +/- 1.2 mm (mean +/- SD). Microscopic study showed sequential tissue alterations with edema, ischemic necrosis, tissue slough, and granulation. Cryolesions were sharply delineated from the normal liver tissue. The radius of necrosis at days 2 and 3 was 17 +/- 0.3 mm (mean +/- SD). It showed good correlation with the cryolesion size measured by intraoperative sonography. The temperature threshold to obtain complete normal liver necrosis was -15 degrees C. We found impedancemetry too difficult to use and not precise enough to monitor cryonecrosis. We conclude that intraoperative sonography and thermometry are useful means to monitor the extent of cryonecrosis during liver cryosurgery.

Mortality and cancer incidence among PVC-processing workers in Sweden

The mortality pattern and the cancer incidence were investigated among 717 men who had been employed for at least 3 months during 1964-1974 in three Swedish PVC-processing plants. The mortality was followed 1964-1986 and the cancer incidence 1964-1984. Expected figures were calculated from Swedish national rates. Among Swedish citizens, the observed mortality and cancer incidence was close to the expected in most diagnoses. Among immigrants, mostly from Finland, there was a marked excess of circulatory deaths. This finding was probably due to the higher incidence of coronary mortality in Finland compared to Sweden. In the whole cohort, five cases of malignant melanoma had occurred as compared to 1.5 expected (SMR = 3.4, 95% confidence limit 1.1-7.9). This may be due to chance but merits further investigation since an increased incidence of malignant melanoma has previously been found among Norwegian PVC-manufacturing workers.

Control of breathing in chronic obstructive pulmonary disease patients at rest and after beta-2 agonist inhalation

Ventilatory function tests, ventilatory cycle analysis, mouth occlusion pressure (P0.1) and effective inspiratory impedance (P0.1/Vt/Ti) were measured in 11 healthy subjects and in 26 patients with chronic obstructive pulmonary disease (COPD). In COPD patients these measurements were repeated 20 min after inhalation of 400 micrograms of fenoterol. In patients we observed an increase of mean inspiratory flow (Vt/Ti), and a decrease of inspiratory time (Ti) and inspiratory duty cycle (Ti/Ttot). P0.1 and effective inspiratory impedance were significantly increased. Moreover, we found a direct correlation between forced expiratory volume in 1 s (FEV1) and ventilatory cycle components (Ti/Ttot, Ti) and an indirect correlation between FEV1 and Vt/Ti.P0.1 was directly correlated with Vt/Ti and indirectly correlated with ventilatory cycle components. These observations lead us to speculate on the possible role of two opposite mechanisms acting on the control of breathing of COPD patients. While the 'intensity' component of the ventilatory cycle would be set to maintain the tidal volume at a constant level, the 'timing' component would act in order to prevent inspiratory muscle fatigue. Furthermore, in patients responsive to beta 2-agonist drugs, fenoterol inhalation would act in synergy with the timing component of ventilatory cycle, lowering P0.1 and the effective inspiratory impedance.

Adrenocorticotropic hormone and catecholamines in maternal, umbilical and neonatal plasma in relation to vaginal delivery

The aim of this study was to evaluate the effect of vaginal delivery on both ACTH and catecholamines (DA, NE, E) secretion in the mother, the fetus (umbilical artery) and the newborn. Blood samples were obtained from 19 normal pregnant women and the corresponding umbilical cords, and from the newborns. Seventeen normal nonpregnant women, matched for age and parity, were also included in the study as "nonpregnant controls". The results demonstrate that in the mother, plasma catecholamines (CA) concentrations during labor and delivery are elevated above the values reported for normal nonpregnant women and there is a predominant E response. The concentrations of CA in umbilical arteries are very high compared to those in the corresponding mother and they fall rapidly after birth. Unlike that in the mother, the predominant CA response to parturition in the fetus and newborn infant is NE. The extraction rate of DA, NE and E from placenta is approximately 60%. The peripheral plasma levels of ACTH in pregnant women during labor are twice and 10 times as high as those observed in the corresponding umbilical arteries and in nonpregnant women respectively. At delivery they increase further. No significant differences are found between the values measured in the arterial cord blood and those in the venous cord blood and in the newborns. A way of explaining the prevalence of E and the higher ACTH/E ratio found in the mother in comparison with the fetus could be that in the mother the stress response to parturition is regulated mainly by the pituitary-adrenal axis, whereas in the fetus there is a prevalent stimulation of the sympathetic nervous system.

Endoscopic placement of enteral feeding tubes

The techniques for placement of feeding tubes using fiberscopes are described and an evaluation of the results obtained in the last 12 months is made. The techniques are discussed and compared with other methods of enteral feeding known at present. It is concluded that placement of feeding tubes by endoscopy can be achieved easily, that it is possible to choose the site of enteric liberation of nutrients under conditions which previously represented contraindications, and that this procedure is free of complications even during long periods of time.