Airway management in the paediatric difficult intubation registry: a propensity score matched analysis of outcomes over time

Background

The Paediatric Difficult Intubation Collaborative identified multiple attempts and persistence with direct laryngoscopy as risk factors for complications in children with difficult tracheal intubations and subsequently engaged in initiatives to reduce repeated attempts and persistence with direct laryngoscopy in children. We hypothesised these efforts would lead to fewer attempts, fewer direct laryngoscopy attempts and decrease complications.

Methods

Paediatric patients less than 18 years of age with difficult direct laryngoscopy were enrolled in the Paediatric Difficult Intubation Registry. We define patients with difficult direct laryngoscopy as those in whom (1) an attending or consultant obtained a Cormack Lehane Grade 3 or 4 view on direct laryngoscopy, (2) limited mouth opening makes direct laryngoscopy impossible, (3) direct laryngoscopy failed in the preceding 6 months, and (4) direct laryngoscopy was deferred due to perceived risk of harm or poor chance of success. We used a 5:1 propensity score match to compare an early cohort from the initial Paediatric Difficult Intubation Registry analysis (August 6, 2012-January 31, 2015, 785 patients, 13 centres) and a current cohort from the Registry (March 4, 2017-March 31, 2023, 3925 patients, 43 centres). The primary outcome was first attempt success rate between cohorts. Success was defined as confirmed endotracheal intubation and assessed by the treating clinician. Secondary outcomes were eventual success rate, number of attempts at intubation, number of attempts with direct laryngoscopy, the incidence of persistence with direct laryngoscopy, use of supplemental oxygen, all complications, and severe complications.

Findings

First-attempt success rate was higher in the current cohort (42% vs 32%, OR 1.5 95% CI 1.3-1.8, p < 0.001). In the current cohort, there were fewer attempts (2.2 current vs 2.7 early, regression coefficient -0.5 95% CI -0.6 to -0.4, p < 0.001), fewer attempts with direct laryngoscopy (0.6 current vs 1.0 early, regression coefficient -0.4 95% CI -0.4 to 0.3, p < 0.001), and reduced persistence with direct laryngoscopy beyond two attempts (7.3% current vs 14.1% early, OR 0.5 95% CI 0.4-0.6, p < 0.001). Overall complication rates were similar between cohorts (19% current vs 20% early). Severe complications decreased to 1.8% in the current cohort from 3.2% in the early cohort (OR 0.55 95% CI 0.35-0.87, p = 0.011). Cardiac arrests decreased to 0.8% in the current cohort from 1.8% in the early cohort. We identified persistence with direct laryngoscopy as a potentially modifiable factor associated with severe complications.

Interpretation

In the current cohort, children with difficult tracheal intubations underwent fewer intubation attempts, fewer attempts with direct laryngoscopy, and had a nearly 50% reduction in severe complications. As persistence with direct laryngoscopy continues to be associated with severe complications, efforts to limit direct laryngoscopy and promote rapid transition to advanced techniques may enhance patient safety.

Funding

None.

Citizen involvement in COVID-19 contact tracing with digital tools: a qualitative study to explore citizens' perspectives and needs

BACKGROUND

Contact tracing (CT) is a key strategy when dealing with outbreaks of infectious diseases such as COVID-19. The scale of the COVID-19 pandemic has often left public health professionals (PHPs), who are responsible for the execution of CT, unable to keep up with the rapid and largescale spread of the virus. To enhance or support its execution, and potentially lower the workload for PHPs, citizens may be more actively involved in CT-tasks that are commonly executed by PHPs (referred to as 'self-led CT'). There is limited insight into citizens' perspectives on and needs for self-led CT for COVID-19. This study aims to explore the perspectives and needs of Dutch citizens on taking more responsibilities in the execution of CT for COVID-19, potentially through the use of digital tools.

METHODS

An exploratory qualitative study was performed, in which online semi-structured interviews were conducted. Questions were based on the Reasoned Action Approach and Health Belief Model. Interviews were audio-recorded and transcribed verbatim. A thematic analysis was conducted to identify citizens' perspectives and needs to participate in self-led CT.

RESULTS

We conducted 27 interviews with Dutch citizens. Seven main themes were identified from the interviews: 1) 'Citizens' perspectives on self-led CT are influenced by prior experiences with regular CT', 2) 'Citizens' felt responsibilities and the perceived responsibilities of the PHS in CT shape their perspectives on self-led CT', 3) 'Anticipated impacts of self-led CT on the CT-process', 4) 'Citizens' attitude towards the application of self-led CT depends on their own perceived skills and the willingness and skills of others', 5) 'Shame and social stigma may hamper participation in self-led CT', 6) 'Concerns about privacy and data security: a barrier for self-led CT', and 7) 'Citizens' perspectives and anticipated needs for the implementation and application of self-led CT in practice'.

CONCLUSIONS

Most interviewees hold a positive attitude towards self-led CT and using digital tools for this purpose. However, their intention for self-led CT may depend on various factors, such as prior experiences with regular CT, and their perceived self-efficacy to participate. Perspectives and needs of citizens should be considered for the future implementation of self-led CT in practice.

Efficacy of a hybrid technique of simultaneous videolaryngoscopy with flexible bronchoscopy in children with difficult direct laryngoscopy in the Pediatric Difficult Intubation Registry

Children with difficult tracheal intubation are at increased risk of severe complications, including hypoxaemia and cardiac arrest. Increasing experience with the simultaneous use of videolaryngoscopy and flexible bronchoscopy (hybrid) in adults led us to hypothesise that this hybrid technique could be used safely and effectively in children under general anaesthesia. We reviewed observational data from the international Pediatric Difficult Intubation Registry from 2017 to 2021 to assess the safety and efficacy of hybrid tracheal intubation approaches in paediatric patients. In total, 140 patients who underwent 180 attempts at tracheal intubation with the hybrid technique were propensity score-matched 4:1 with 560 patients who underwent 800 attempts with a flexible bronchoscope. In the hybrid group, first attempt success was 70% (98/140) compared with 63% (352/560) in the flexible bronchoscope group (odds ratio (95%CI) 1.4 (0.9-2.1), p = 0.1). Eventual success rates in the matched groups were 90% (126/140) for hybrid vs. 89% (499/560) for flexible bronchoscope (1.1 (0.6-2.1), p = 0.8). Complication rates were similar in both groups (15% (28 complications in 182 attempts) hybrid; 13% (102 complications in 800 attempts) flexible bronchoscope, p = 0.3). The hybrid technique was more likely than flexible bronchoscopy to be used as a rescue technique following the failure of another technique (39% (55/140) vs. 25% (138/560), 2.1 (1.4-3.2) p < 0.001). While technically challenging, the hybrid technique has success rates similar to other advanced airway techniques, few complications and may be considered an alternative technique when developing an airway plan for paediatric patients whose tracheas are difficult to intubate under general anaesthesia.

Evaluation of culturally sensitive educational video for informed screening decisions among migrants

Background

In the Netherlands, especially Turkish- and Moroccan-Dutch women show low cervical cancer screening participation and limited informed decision-making in this regard. To meet the needs of these women, a culturally sensitive educational video was developed. The objective was to evaluate the effect of the video on informed decision-making regarding cervical cancer screening participation among Turkish and Moroccan women aged 30-60 years in the Netherlands.

Methods

Initial respondents were recruited via several social media platforms and invited to complete an online questionnaire. Following respondent-driven sampling, respondents were asked to recruit a number of peers from their social network to complete the same questionnaire. Respondents were randomly assigned to the control condition (current information brochure) or intervention condition (brochure and video). We evaluated the added effect of the video on knowledge, attitude, intention, and informed decision-making using intention-to-treat analyses.

Results

The final sample included 686 Turkish- and 878 Moroccan-Dutch women. Of this sample, 793 were randomised to the control group (350 Turkish and 443 Moroccan) and 771 to the intervention group (336 Turkish and 435 Moroccan). Among Turkish-Dutch women, 33.1% of the control respondents and 40.5% of the intervention respondents consulted the brochure (not statistically significant). Among Moroccan-Dutch women, these percentages were 28.2% and 37.9%, respectively (P = 0.003). Of all intervention respondents, 96.1% (Turkish) and 84.4% (Moroccan) consulted the video. The video resulted in more positive screening attitudes among Moroccan-Dutch women, in comparison to the brochure (74.3% versus 68.4%, P = 0.07).

Conclusions

Our short, easily implementable video resulted in more positive screening attitudes in Turkish- and Moroccan-Dutch women and can thus contribute to informed cervical cancer screening decisions.

Key messages

Anesthesia in Children With Pulmonary Hypertension: Clinically Significant Serious Adverse Events Associated With Cardiac Catheterization and Noncardiac Procedures

OBJECTIVES

To determine the incidence of clinically significant serious adverse events in a contemporary population of pediatric patients with pulmonary hypertension who require anesthesia and identify factors associated with adverse outcomes.

DESIGN

A retrospective, cross-sectional study.

SETTING

A single-center quaternary-care freestanding children's hospital in the northeastern United States.

PARTICIPANTS

Pediatric patients with pulmonary hypertension based on hemodynamic criteria on cardiac catheterization during a 3-year period from 2015 to 2018.

INTERVENTIONS

Anesthesia care for cardiac catheterization, noncardiac surgery, and diagnostic imaging.

MEASUREMENTS AND MAIN RESULTS

Two hundred forty-nine children underwent 862 procedures, 592 for cardiac catheterization and 278 for noncardiac surgery and diagnostic imaging. The median age was 1.6 years, and the weight was 9.5 lbs. On index catheterization, median pulmonary artery pressure was 36 mmHg, and the pulmonary vascular resistance was 5.1 indexed Wood units. Ten percent of anesthetics were performed with a natural airway, and 80% used volatile anesthetics. Serious adverse events occurred in 26% of procedures (confidence interval [CI], 22%-30%). The rate of periprocedural cardiac arrest was 8 per 1,000 anesthetic administrations. In multivariate analysis, younger age (adjusted odds ratio [aOR], 1.4 per year; CI, 1.1-1.9; p = 0.01), location in the catheterization laboratory (aOR, 5.1; CI, 1.7-16; p = 0.004), and longer procedure duration (aOR, 1.3 per 30 minutes; CI, 1.1-1.4; p = 0.001) were associated with serious adverse events. Patients with a tracheostomy in place were less likely to experience an adverse event (aOR, 0.1; CI, 0.04-0.5; p = 0.001). The primary anesthetic technique was not associated with adverse events. Interventional cardiac catheterization was associated with an increased incidence of adverse events compared with diagnostic catheterization (42% v 21%; OR, 2.23; CI, 1.5-3.3; p < 0.001).

CONCLUSIONS

Serious adverse events were common in this cohort. Careful planning to minimize anesthesia time in young children with pulmonary hypertension should be undertaken, and these factors considered in designing risk mitigation strategies.

Lessons from COVID-19: A reflection on the strengths and weakness of early consensus recommendations for pediatric difficult airway management during a respiratory viral pandemic using a modified Delphi method

BACKGROUND

The authors recognized a gap in existing guidelines and convened a modified Delphi process to address novel issues in pediatric difficult airway management raised by the COVID-19 pandemic.

METHODS

The Pediatric Difficult Intubation Collaborative, a working group of the Society for Pediatric Anesthesia, assembled an international panel to reach consensus recommendations on pediatric difficult airway management during the COVID-19 pandemic using a modified Delphi method. We reflect on the strengths and weaknesses of this process and ways care has changed as knowledge and experience have grown over the course of the pandemic.

RECOMMENDATIONS

In the setting of the COVID-19 pandemic, the Delphi panel recommends against moving away from the operating room solely for the purpose of having a negative pressure environment. The Delphi panel recommends supplying supplemental oxygen and using videolaryngoscopy during anticipated difficult airway management. Direct laryngoscopy is not recommended. If the patient meets extubation criteria, extubate in the OR, awake, at the end of the procedure.

REFLECTION

These recommendations remain valuable guidance in caring for children with anticipated difficult airways and infectious respiratory pathology when reviewed in light of our growing knowledge and experience with COVID-19. The panel initially recommended minimizing involvement of additional people and trainees and minimizing techniques associated with aerosolization of viral particles. The demonstrated effectiveness of PPE and vaccination at reducing the risk of exposure and infection to clinicians managing the airway makes these recommendations less relevant for COVID-19. They would likely be important initial steps in the face of novel respiratory viral pathogens.

CONCLUSIONS

The consensus process cannot and should not replace evidence-based guidelines; however, it is encouraging to see that the panel's recommendations have held up well as scientific knowledge and clinical experience have grown.

Aerosol barriers in pediatric anesthesiology: Clinical data supports FDA caution

BACKGROUND

The onset of the COVID19 pandemic drove the rapid development and adoption of physical barriers intended to protect providers from aerosols generated during airway management. We report our initial experience with aerosol barrier devices in pediatric patients and raise concerns that they may increase risk to patients.

METHODS

In March 2020, we developed and implemented simulation training and use of plastic aerosol barrier devices as a component of our perioperative COVID-19 workflow. As part of our quality improvement process, we obtained detailed feedback via a web-based survey after cases were performed while using these aerosol barriers.

RESULTS

Between March and June 2020, 36 pediatric patients age 1mo-18years with anatomically normal airways and either PCR confirmed or suspected COVID-19 were intubated under an aerosol barrier as part of urgent or emergent anesthetic care at our institution. Experienced providers had more difficulty than expected in six (16.7%) of the cases with four cases requiring multiple attempts to secure the airway and two cases involving pronounced difficulty in a single attempt. The aerosol barrier was perceived as a contributing factor to difficulty in all cases.

CONCLUSION

The use of barriers may result in unanticipated difficulties with airway management, particularly in pediatric patients, which could lead to hypoxemia or other patient harm. Our initial experience in pediatric patients is the first such report in patients and provides clinical data which corroborates the simulation data prompting the FDA to withdraw support of barriers.

Pediatric Airway Management in COVID-19 Patients: Consensus Guidelines From the Society for Pediatric Anesthesia's Pediatric Difficult Intubation Collaborative and the Canadian Pediatric Anesthesia Society

The severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019 [COVID-19]) pandemic has challenged medical systems and clinicians globally to unforeseen levels. Rapid spread of COVID-19 has forced clinicians to care for patients with a highly contagious disease without evidence-based guidelines. Using a virtual modified nominal group technique, the Pediatric Difficult Intubation Collaborative (PeDI-C), which currently includes 35 hospitals from 6 countries, generated consensus guidelines on airway management in pediatric anesthesia based on expert opinion and early data about the disease. PeDI-C identified overarching goals during care, including minimizing aerosolized respiratory secretions, minimizing the number of clinicians in contact with a patient, and recognizing that undiagnosed asymptomatic patients may shed the virus and infect health care workers. Recommendations include administering anxiolytic medications, intravenous anesthetic inductions, tracheal intubation using video laryngoscopes and cuffed tracheal tubes, use of in-line suction catheters, and modifying workflow to recover patients from anesthesia in the operating room. Importantly, PeDI-C recommends that anesthesiologists consider using appropriate personal protective equipment when performing aerosol-generating medical procedures in asymptomatic children, in addition to known or suspected children with COVID-19. Airway procedures should be done in negative pressure rooms when available. Adequate time should be allowed for operating room cleaning and air filtration between surgical cases. Research using rigorous study designs is urgently needed to inform safe practices during the COVID-19 pandemic. Until further information is available, PeDI-C advises that clinicians consider these guidelines to enhance the safety of health care workers during airway management when performing aerosol-generating medical procedures. These guidelines have been endorsed by the Society for Pediatric Anesthesia and the Canadian Pediatric Anesthesia Society.

Emerging trends, techniques, and equipment for airway management in pediatric patients

Pediatric patients present unique anatomic and physiologic considerations in airway management, which impose significant physiologic limits on safe apnea time before the onset of hypoxemia and subsequent bradycardia. These issues are even more pronounced for the pediatric difficult airway. In the last decade, the development of pediatric sized supraglottic airways specifically designed for intubation, as well as advances in imaging technology such that current pediatric airway equipment now finally rival those for the adult population, has significantly expanded the pediatric anesthesiologist's tool kit for pediatric airway management. Equally important, techniques are increasingly implemented that maintain oxygen delivery to the lungs, safely extending the time available for pediatric airway management. This review will focus on emerging trends and techniques using existing tools to safely handle the pediatric airway including videolaryngoscopy, combination techniques for intubation, techniques for maintaining oxygenation during intubation, airway management in patients at risk for aspiration, and considerations in cannot intubate cannot oxygenate scenarios.

Reasons for cervical cancer screening participation among Turkish- and Moroccan-Dutch: focus groups

Background

Cervical cancer (CC) is ranked fourth most frequently diagnosed cancer in women worldwide. Compared to the 79% CC screening participation rate of native Dutch women, the rate of 64% among Turkish- and 53% among Moroccan-Dutch women is considerably lower. Our aim was to explore reasons for CC screening (non)participation of Turkish- and Moroccan-Dutch women, and their attitude towards self-sampling.

Methods

Six focus groups were conducted in March and April 2019 with Turkish (n = 25) and Moroccan (n = 20) women in the Netherlands, aged 30-60 years. Questions were based on an extended Health Belief Model. Discussions were transcribed verbatim and thematically analysed.

Results

We found that women lack knowledge and awareness about CC. Barriers for screening were lack of a good command of the Dutch language, having a male as general practitioner, fatalism, shame and taboo related to the intimate procedure, and the association of CC with lack of femininity and infertility. Other barriers were fears of the test result, cancer, suffering, death, and leaving their children behind after death. Facilitators were perceived severity of disease, social support, and short procedure time. Additional religious facilitators included the responsibility to take care of one’s own health using medical facilities that God provided. Differences were found between Turkish and Moroccan women, such as lack of a good command of the Dutch language. Conflicting attitudes were found regarding self-sampling. Although perceived easy and accessible, women were hesitant whether they could sample correctly. Overall, women preferred a physician-taken smear to a self-sample.

Conclusions

Several barriers and facilitators for CC screening participation were identified that can be used to design tailored information materials. Women’s doubts about incorrect self-sampling should be taken into account to encourage self-sampling among nonparticipating Turkish and Moroccan women.

Key messages

Important barriers and facilitators were identified that can be used to well-inform Turkish and Moroccan women. To promote self-sampling, women’s attitudes on their self-efficacy should be explored.

Example C: Using online respondent-driven detection for communicable disease control

Online respondent-driven detection (online-RDD) is a novel method of case-finding that may enhance contact tracing (CT). However, the opportunities and barriers of online-RDD for public health practice have not yet been investigated from the perspective of public health professionals (PHPs). Therefore, it is unclear what the potential strengths and limitations of online-RDD for CT are.

We conducted a sequential exploratory mixed methods research. First, we conducted semi-structured interviews with Dutch PHPs involved in CT. Questions were derived from the diffusion of innovations theory. Second, we distributed an online-questionnaire to 260 Dutch PHPs to study the main findings in a larger population. We used hypothetical scenario’s (scabies, shigella, and mumps) to elicit PHPs’ perceptions of online-RDD.

Twelve interviews were held. Response rate to the online-questionnaire was 31% (n = 70). Four themes related to characteristics of online-RDD that influenced PHPs’ intention to adopt online-RDD emerged: advantages over traditional CT, task conflicts and opportunity costs, public health risks, and situational compatibility. PHPs believed online-RDD may enhance CT through increased reach, low-key communication options, and saving time. Limitations were foreseen in the delivery of measures, supporting patients and contacts, missing information and contacts, and causing unrest. Online-RDD may be particularly applicable in situations with digitally skilled and literate target populations, low urgency, low time-pressure, and a simple perspective for action. A majority of PHPs (70%) had a positive adoption intention towards online-RDD.

PHPs perceived online-RDD as beneficial to public health practice. Further development of online-RDD should focus on facilitating opportunities for personal contact between PHPs, patients and contacts. A comparative study of ‘traditional’ CT and online-RDD could yield further insights in the potential of online-RDD for public health practice.

Synthesis and anti-human immunodeficiency virus type 1 integrase activity of hydroxybenzoic and hydroxycinnamic acid flavon-3-yl esters

A series of new hydroxybenzoic and hydroxycinnamic acid flavon-3-yl esters were synthesized in order to obtain compounds targeting the human immunodeficiency virus (HIV) type 1 integrase (IN). The esters were tested for anti-IN and anti-reverse transcriptase (RT) activity in enzyme assays and for anti-HIV-1, anti-proliferative and anti-topoisomerase activity in cell-based assays. In enzyme assays, the two gallic acid flavon-3-yl esters showed a notable IN inhibition (IC50 values were 8.3 and 9.1 microM, respectively), while the two caffeic acid flavon-3-yl esters exhibited a modest activity (IC50 75 and 60 microM, respectively). Replacement of hydroxyl groups resulted in loss of potency. Caffeic acid 3',4'-dichloroflavon-3-yl ester also inhibited the RT activity whereas it was not active on human topoisomerases. It therefore represents an interesting example of a compound specifically targeting more than one step of the virus replication cycle.

N-omega-carbethoxypentyl-4-quinolones: a new class of leukotriene biosynthesis inhibitors

6-[(4-Quinolinyl)oxy]hexanoic acids and the corresponding esters were designed and synthesized as inhibitors of the production of arachidonic acid metabolites. The inhibitory activities were assayed in vitro by evaluation of serum leukotriene B4 and thromboxane B2 production. While all 6-[(4-quinolinyl)oxy]hexanoic acids and their esters proved to be inactive, the N-alkyl-4-quinolones, obtained as by-products in their synthesis, were found to be a new class of leukotriene biosynthesis inhibitors.

Effect of chloro-, cyano-, and amidino-substituted flavanoids on enterovirus infection in vitro

Synthetic flavans, isoflavans and isoflavenes substituted with chloro, cyano and amidino groups were tested for their in vitro activity against poliovirus type 2, Coxsackie virus B4, echovirus type 6 and enterovirus 71. Plaque-reduction assays showed that substituted 3-(2H)-isoflavenes, carrying a double bond in the oxygenated ring, possess antiviral activity higher than that of the corresponding isoflavans. The most effective compounds were 4'-chloro-6-cyanoflavan and 6-chloro-4'-cyanoflavan. Studies on the mechanism of action of these two compounds suggested an effect on the early stages of viral replication.

Sexual differences in the effect of the GABAergic system on LH secretion and in the hypothalamic ontogenesis of GABAA receptors in prepubertal rats

The administration of aminooxyacetic acid (AOAA), which increases hypothalamic GABA concentrations, induced a significant increase in LH levels in female rats of 12, 16 and 18 days of age. This stimulatory effect of AOAA on serum LH levels was not observed at 21 and 25 days of age whereas a significant decrease in the LH concentrations by AOAA was found at 30 days of age. The neonatal androgenization of female rats abolished the effects of AOAA and no effects of AOAA were found in male rats at the different ages studied. The muscimol binding sites in medial basal and preoptic anterior hypothalamic areas showed a significant different sexual ontogenic pattern. Males rats castrated at birth showed a very similar ontogenic pattern of [3H]muscimol binding sites to female rats and significantly different to male control rats. It is concluded that there are sexual differences in the effect of GABAergic system on LHRH-LH secretion and in the development of hypothalamic GABAA receptors during sexual maturation. These differences are probably connected with the neonatal exposure to androgens that would induced changes in the composition and probably in the properties of GABAA receptor that in turn modified its effects on LHRH neurons.

Synthesis of some guanylhydrazones and imidazolinylhydrazones as thromboxane-synthase and platelet aggregation inhibitors

The imidazolinylhydrazones of (3-pyridinyloxy)-acetaldehyde and of 6-[3-(2-formyl-pyridinyl)oxy]hexanoic acid were synthesized as cyclic analogues of the corresponding guanylhydrazones which were found to be selective inhibitors of human thromboxane-synthase. The benzene isosters were also prepared in order to define the importance of the ring nitrogen for the activity. Moreover, the guanyl- and imidazolinyl-hydrazones of two 6-[(3-pyridinyl)oxy]hexanoic acids showing in the 2 position an alkyl chain with an alpha, beta-unsaturated ketonic function were prepared. Imidazolinylhydrazones 7 and 18 are selective inhibitors of thromboxane-synthase, while the two guanylhydrazones 14 and 15 which do not affect prostanoid biosynthesis seemed to be antagonists at the thromboxane receptor.

Constituents of Eriobotrya japonica. A study of their antiviral properties

The CHCl3 extract of Eriobotrya japonica from an Italian source was shown to contain four new triterpene esters, namely, 23-trans-p-coumaroyltormentic acid [1], 23-cis-p-coumaroyltormentic acid [2], 3-O-trans-caffeoyltormentic acid [3], and 3-O-trans-p-coumaroylrotundic acid [4], in addition to three common ursolic acid derivatives 5, 6, and 7. An investigation of the antiviral properties of compounds 1-7 revealed that only 3 significantly reduced rhinovirus infection. The compounds were ineffective towards human immunodeficiency virus type 1 (HIV-1) and Sindbis virus replication.

Synthesis and binding properties to GABA receptors of 3-hydroxypyridinyl- and 3-hydroxypiperidinyl-analogues of baclofen

The synthesis of 3-(3-hydroxy-2-pyridinyl)propanoic acid, 3-(3-hydroxy-2-pyridinyl)-4-aminobutanoic acid, their corresponding piperidine compounds, and of some cyclized derivatives is described. In in vitro assays none of the new compounds shows any noteworthy affinity for GABAA or GABAB receptors; only (R,S)-3-(3-hydroxy-2-pyridinyl)-4-aminobutanoic acid and its lactam inhibited in some degree [3H]GABA binding, at 10(-4) M concentration, with low specificity as regards the two receptors.

Mechanism of action of the antirhinovirus flavanoid 4',6-dicyanoflavan

4',6-Dicyanoflavan (DCF), a new antirhinovirus compound, was shown to inhibit an early event of rhinovirus type 1B replication in HeLa cells. When DCF was present from the beginning of infection or was added no later than the first hour of infection, the compound completely prevented viral RNA and protein synthesis and the virus-induced shutoff of host translation. DCF had no adverse effect either on virus binding to the cell membrane or on virus penetration into cells, whereas it delayed the uncoating kinetics of neutral redencapsidated rhinovirus. DCF also prevented mild acid or thermal inactivation of virus infectivity, although it reversibly interacted with virions. These results suggest that the stabilizing effect of DCF on virion capsid conformation is responsible for uncoating inhibition.

Antiviral activity of constituents of Tamus communis

The antiviral activity of the phenanthrene derivatives 1-6, of the spyrostane triglycosides dioscin (7) and gracillin (8), of the furostanol tetraglycosides methylprotodioscin (9), its (25S) epimer methylprotoneodioscin (10), and methylprotogracillin 11, have been tested towards two RNA viruses: vesicular stomatitis virus and human rhinovirus type 1B. All these products were extracted from the rizomes of Tamus communis L; compound 11 was isolated also from Asparagus cochinchinesis, together with pseudoprotodioscin (12), a 20 (22)-unsaturated furostanoside, which was also investigated for antiviral activity. The results were of some interest mainly for the phenanthrene derivatives.

Deletion of two growth-factor repeats from the low-density-lipoprotein receptor accelerates its degradation

The region of the low-density-lipoprotein (LDL) receptor showing sequence similarity to the epidermal-growth-factor (EGF) precursor is required for LDL binding and the acid-induced dissociation of ligand and receptor. We describe here a naturally occurring mutant LDL receptor, found in a patient with homozygous familial hypercholesterolaemia, which lacks the first two growth-factor-like repeats of the EGF-precursor-like ('homology') domain. The mutation in the receptor gene is a 2.5 kb deletion including exons 7 and 8. The molecular mass of the mutant receptor (145 kDa) was approx. 15 kDa smaller than the normal LDL receptor. The mutant receptors were derived from precursors (105 kDa) that apparently underwent normal processing. Fibroblasts from the patient had high-affinity binding sites for the the apolipoprotein E-containing ligand, beta VLDL, but did not bind LDL. In the presence of beta VLDL, receptors were rapidly degraded. The mutant receptors also displayed an abnormally rapid turnover, about four times faster than that of normal receptors, in the absence of ligand; this accelerated degradation accounted for the low level of expression of mutant receptors in up-regulated cells. These data support a role for the growth-factor-like repeats in the binding of LDL (but not beta VLDL) and in receptor recycling, and indicate that a normal rate of turnover of unoccupied receptors is dependent on the integrity of these segments of the protein.

Iron dextran in the treatment of iron-deficiency anaemia of pregnancy. Haematological response and incidence of side-effects

Sixty pregnant patients with a haemoglobin (Hb) less than 8 g/dl and proven iron-deficiency anaemia were randomly allocated to two treatment groups. Group A received the usual recommended dose of iron dextran (Imferon; Fisons) and group B received two-thirds of the recommended dose. A further 30 patients received oral iron (group C). There was no difference in Hb value between the three groups 4 weeks after treatment or 3 months after delivery. At 6 months after delivery, a higher mean Hb value was found in the patients in group A than those in groups B and C. Significantly higher serum ferritin levels were found in group A and this difference was still present 6 months postnatally. There was no significant difference in the incidence of delayed reactions between the two groups who received iron dextran.

In vitro effect of synthetic flavanoids on astrovirus infection

In this study we investigated the activity of halogeno-, cyano- and amidino-isoflavenes, isoflavans and flavans on the multiplication of human astroviruses. These are naked small round viruses which have been recognized as causative agents of human gastroenteritis, and whose capsid proteins are similar to those of picornaviruses. Although all drugs tested caused a dose-dependent reduction of viral antigen synthesis as monitored by immunofluorescence, the chloro derivatives were the most effective.

Activities and mechanisms of action of halogen-substituted flavanoids against poliovirus type 2 infection in vitro

The effects of some halogen-substituted flavanoids (dichloroflavan, halogenated isoflavans, and isoflavenes) on poliovirus type 2 infection was examined. Only two isoflavenes exhibited a significant inhibitory activity on the virus-induced cytopathic effect and plaque formation. In a single cycle of viral replication, both compounds reduced the viral yield by approximately 90%. The presence of the isoflavenes from the beginning of infection or during the adsorption period only prevented the shutoff of host translation and viral RNA and protein synthesis, suggesting that the drugs blocked an early step of viral replication. Indeed, both isoflavenes were not virucidal, did not protect virus infectivity from heat inactivation, and had no measurable effect on the binding of virus to cells, viral penetration, and uncoating of the viral RNA. In contrast, both compounds significantly reduced the infectivity of free viral RNA. The possibility that compounds interfere with poliovirus replication at a very early stage of translation of the input RNA is discussed.

Dimethyl cathate: synthesis and pharmacological investigation

Dimethyl cathate was synthesized through a reaction sequence starting from 3,4-pyridinedicarboxylic acid anhydride, and hydrolyzed to the not yet described cathic acid. Pharmacological screening procedures only showed a protection against the convulsive effect of pentylenetetrazol.

Effect of isoflavans and isoflavenes on the infection of Frp/3 cells by hepatitis A virus

The effect of 6,4'-dichloroflavan and of isoflavan and isoflavene derivatives on hepatitis A virus (HAV) infection in a monkey cell line (Frp/3 cells) was studied. These compounds were not virucidal and had no measurable effect on the adsorption of virus to the cells at 0 degrees C, whereas they exerted an inhibitory effect on viral antigen synthesis when incubated with the infected cells during HAV multiplication. Among the substances tested, 6,4'-dichloroflavan and 6,4'-dichloroisoflavan showed the highest activity. These compounds are postulated to interact with an early stage (penetration and/or uncoating) of HAV infection.

Effect of isoflavans and isoflavenes on rhinovirus 1B and its replication in HeLa cells

The effect of newly synthesized halogenated isoflavans and isoflavenes on human rhinovirus 1B (HRV 1B) infection of HeLa cells has been examined. Both series of drugs inhibited virus plaque formation in cell cultures, isoflavans being more effective than isoflavenes. Cells pretreated with compounds before challenge with HRV 1B became resistant to the virus-induced cytopathic effect. The antiviral state induced by the most active compounds persisted for at least 10 h and did not appear to be mediated by interferon production. Experiments whereby the compounds were added at varying times indicated that the isoflavans and isoflavenes interfere with early events of virus replication without affecting virus binding to the cell membrane. In addition to their effects on virus multiplication, the isoflavans were also found to have a direct action on the virus. The inhibitory effect on virus infectivity required extraction with chloroform for reversal. Isoflavans also protected the virions against mild acid or heat inactivation.

Inhibition of thromboxane biosynthesis by 3-pyridinol carboxypentyl ethers substituted with a hydroxylated octyl chain

Racemic 6-[4-(3'-hydroxy-1'-octenyl)-3-pyridyloxy]hexanoic and 6-[4-(3'-hydroxyoctyl)-3-pyridyloxy] exanoic acids have been synthesized and their activity as inhibitors of the biosynthesis of thromboxane A2 in human serum has been studied, in comparison with isomers having the eight-carbon chain in the 2 position. Very high, selective activity was found for the new 4-substituted 3-pyridinol ethers, whereas the 2-substituted compounds showed no action.

In vitro inhibition of Trichomonas vaginalis growth by some ortho-phenacyloxy-benzyl alcohols and their derivatives

Some phenacyl ethers of different ortho-hydroxy-benzyl alcohols and analogues have been synthesized and tested for the in vitro activity towards Trichomonas vaginalis. The most active compounds had a minimum inhibitory concentration of 6.25 micrograms/ml and appeared to be of a certain interest as representative of a new type of anti-Trichomonas substances not containing a nitro group.

Synthesis of guanylhydrazones derived from 3-pyridinol and evaluation of their effect on serum thromboxane B2 and prostaglandin E2 production

3-Pyridyloxyacetaldehyde guanylhydrazone and the guanylhydrazones of pyridine-2- and -4-aldehydes substituted at the 3-position with the omega-carboxypentyloxy chain were synthesized in order to evaluate their activity as thromboxane synthase inhibitors in vitro. The tested compounds inhibit thromboxane B2 biosynthesis in human serum. The first appears to be a selective inhibitor of thromboxane synthase, since there was a concomitant rise in Prostaglandin E2 (PGE2) level. The derivative of 4-pyridinealdehyde was the more active one of the other two compounds but it also markedly lowered PGE2 biosynthesis proving to be an inhibitor of cyclooxygenase.

[Synthesis of p-aminobenzenesulfonyldiazine]

New sulfones were synthesized; these are analogues of bis-(4-aminophenyl)sulfone (DDS) but contain, instead of one benzene nucleus, a heterocycle that is a pyrimidine, pyrazine or pyridazine nucleus. This was substituted with amine, methoxy, methyl groups or halogens in order to obtain long-acting drugs, similarly to those obtained in the field of sulfonamides. The synthesis was accomplished by reaction of sodium p-amino- or p-acetamidobenzensulfinate with the corresponding halodiazine; only the p-aminophenyl 3-aminopyridazin-6-yl sulfone was obtained by acid hydrolysis. The compounds showed good antitubercular activity in vitro.

The three dose components of negative pion beam and their role in pion radiotherapy

A new method has been developed for analyzing therapeutic negative pion beams into three LET (linear energy transfer) dose components inherent in such a beam. The technique utilizes thin silicon detectors to obtain pulse height spectra produced by the various particles in the beam traversing the detectors. It is shown that a low LET group is correlated with the incoming pions, muons and electrons; a medium LET group corresponds to protons, deuterons, tritons, and high energy alpha particles; and a high LET group is due to low energy alpha particles, 3He and recoil particles. Several beams used clinically have been studied.

Bilateral herniation of renal pelves: a complication of cutaneous pyelostomy

The first reported case of bilateral herniations of the renal pelves as a complication of cutaneous pyelostomy is presented. We describe a modification of the original surgical technique that may prevent herniation, based on fixation of the pelvis to the lumbodorsal fascia as well as the cut edge of the pelvis to the skin. In our patient the bilateral herniations were corrected by repairing the fascial defects and suturing of the pelvis to the fascia.

[New isoxazol /5,4-b/ pyridine-3-acetic acids]

We prepared two isoxazol [5,4-b] piridin-3-acetic acids by two different synthetic methods. 4,6-Dimethylisoxazole [5,4-b] pyridin-3-acetic acid was obtained by reaction with hydroxylamine of 4-hydroxy-5,7-dimethyl-2H-pyrano [2,3-b]pyridin-2-one, which was in turn prepared starting from 2-hydroxy-3-acetyl-4,6-dimethylpyridine. Isoxazolo [5,4-b] pyridine-3-acetic acid was obtained starting from 3-methyl-5-aminoisoxazole and has shown interesting auxin activity.

Structure-activity relationships in reactivators of organophosphorus-inhibited acetylcholinesterase. 10. Hydroxyiminomethylarylethenylpyridine methiodides

The synthesis of styrylpyridine methiodides where a hydrogen of the pyridyl moiety was replaced by the hydroxyiminomethyl group produced highly effective inhibitors of acetylcholinesterase. As starting materials 4-methylpyridine-2-aldoxime and 2-methylpyridine-4-aldoxime methiodides were prepared which, together with 4-imidazolylethenyl-pyridine-2-aldoxime methiodide, were the only substances for which some activity as reactivators of phosphorylated electric eel cholinesterase in vitro could also be found.

[Isoxazoles substituted with 4-pyridyl and o-chlorophenyl radicals]

By reaction of suitable hydroxamic acids chlorides with beta-ketoesters, we have prepared the ethyl esters of isoxazol-4-carboxylic acids, substituted in the 3- and 5-positions with 4-pyridyl and o-chlorophenyl groups, and some of their esters and amides of pharmaceutical interest. 3-(4-Pyridyl)-5-(o-chlorophenyl)isoxazole was obtained either by decarboxylation of the acid or by oxidation of the syn and anti oximes of 3-(o-chlorophenyl)-1-(4-pyridyl)-2-propen-1-one; from the syn oxime the corresponding isoxazoline was also obtained. Pharmacological screening shows that some of the new compounds have a myolytic activity.

An empirical validation of the relation between Rorschach white-space and oppositionality

Although the Rorschach white-space response ( S) has been traditionally interpreted in terms of oppositional tendencies, attempts to validate this relationship have been hampered by the lack of a criterion-specific measure of oppositionality. As part of a broader investigation of the relationship between handedness and personality styles, a rating-scale measure of oppositionality was designed. Oppositionality ratings were obtained for 40 male Navy enlisted men and correlated with white-space scores earned by each S on the Rorschach test. Significant positive correlations between degree of rated oppositionality and amount of white-space perception were obtained. High levels of white-space response were found to be most effective in prediction of degree of rated oppositionality.