Reviewing essential public health functions in the Eastern Mediterranean Region post COVID-19 pandemic: a foundation for system resilience

The COVID-19 pandemic exposed vulnerabilities in many health systems worldwide with profound implications for health and society. The public health challenges experienced during the pandemic have highlighted the importance of resilient health systems, that can adapt and transform to meet the population's evolving health needs. Essential public health functions (EPHFs) offer a holistic, integrated and sustainable approach to public health by contributing to achieving several health priorities and goals. In recent years, there has been a focused effort to conceptualise and define the EPHFs. In this paper, we describe the collaborative approach undertaken by the WHO Eastern Mediterranean Region (EMR) and UK Health Security Agency and present the findings and results of the revised EPHFs, in view of lessons learnt from the COVID-19 pandemic and the current priorities for countries across the EMR. This included conducting a desktop review, a gap and bottleneck analysis and stakeholder consultation to arrive at the revised EPHF model including four enablers and nine core functions, including a new function: public health services. The EPHFs will offer countries a complementary and synergistic approach to strengthen health systems and public health capacities and contribute to the region's ability to effectively respond to future health challenges and emergencies. By focusing on the EPHFs, countries can work towards ensuring health security as an integral goal for the health system besides universal health coverage, thus strengthening and building more resilient and equitable health systems.

Syndemic health crises-The growing role of National Public Health Institutes in shaping a coordinated response

Countries across the world are experiencing syndemic health crises where infectious pathogens including COVID-19 interact with epidemics of communicable and non-communicable diseases. Combined with war, environmental instability and the effects of soaring inflation, a public health crisis has emerged requiring an integrated response. Increasingly, national public health institutes (NPHIs) are at the forefront of leading this, as demonstrated at the 2022 Annual Meeting of the International Association of National Public Health Institutes (IANPHI). These effects are particularly evident where conflict is exacerbating health crises in Ukraine and Somalia. In Ukraine, medical and public health workers have been killed and infrastructure destroyed, which require major efforts to rebuild to international standards. In Somalia, these crises are magnified by the effects of climate change, leading to greater food insecurity, heat-related deaths and famine. National public health institutes are crucial in these contexts and many others to support integrated political responses where health challenges span local, national and international levels and involve multiple stakeholders. This can be seen in strengthening of Integrated Disease Surveillance and work towards the Sustainable Development Goals. National public health institutes also provide integration through the international system, working jointly to build national capacities to deliver essential public health functions. In this context, the 2022 IANPHI Annual meeting agreed the Stockholm Statement, highlighting the role that NPHIs play in tackling the causes and effects of interconnected global and local challenges to public health. This represents an important step in addressing complex health crises and syndemics which require whole-of-society responses, with NPHIs uniquely placed to work across sectors and provide system leadership in response.

Global and regional governance of One Health and implications for global health security

The apparent failure of global health security to prevent or prepare for the COVID-19 pandemic has highlighted the need for closer cooperation between human, animal (domestic and wildlife), and environmental health sectors. However, the many institutions, processes, regulatory frameworks, and legal instruments with direct and indirect roles in the global governance of One Health have led to a fragmented, global, multilateral health security architecture. We explore four challenges: first, the sectoral, professional, and institutional silos and tensions existing between human, animal, and environmental health; second, the challenge that the international legal system, state sovereignty, and existing legal instruments pose for the governance of One Health; third, the power dynamics and asymmetry in power between countries represented in multilateral institutions and their impact on priority setting; and finally, the current financing mechanisms that predominantly focus on response to crises, and the chronic underinvestment for epidemic and emergency prevention, mitigation, and preparedness activities. We illustrate the global and regional dimensions to these four challenges and how they relate to national needs and priorities through three case studies on compulsory licensing, the governance of water resources in the Lake Chad Basin, and the desert locust infestation in east Africa. Finally, we propose 12 recommendations for the global community to address these challenges. Despite its broad and holistic agenda, One Health continues to be dominated by human and domestic animal health experts. Substantial efforts should be made to address the social-ecological drivers of health emergencies including outbreaks of emerging, re-emerging, and endemic infectious diseases. These drivers include climate change, biodiversity loss, and land-use change, and therefore require effective and enforceable legislation, investment, capacity building, and integration of other sectors and professionals beyond health.

Building the evidence base for global health policy: the need to strengthen institutional networks, geographical representation and global collaboration

National public health institutes and WHO collaborating centres, and their global networks, are a key resource to support public health system strengthening with essential public health functions and generate evidence for health policy central to national health and socioeconomic development. The COVID-19 pandemic has laid bare global inequities in public health capacities, made urgent the need to examine sources of global knowledge and understand how to better invest in and use public health institutes and their capacities. This analysis paper incorporates experiences and perspectives from the WHO and International Association of National Public Health Institutes including the ongoing pandemic and work conducted in the UK-WHO ‘Tackling Deadly Diseases in Africa Programme’. We acknowledge geographical disparities in public health capacities both within and across countries and regions, provide examples of novel ways of working for global health actors, and define the challenging environment in which public health authorities operate. We identify four incentives for all countries to invest in public health and strengthen institutions: (1) transparency and trust; (2) socioeconomic dividends; (3) collective health protection and (4) knowledge sharing and equity. By pursuing shared priorities; enabling voices from low-resource settings to be more equitably heard; facilitating collaboration and learning within and across regions, we articulate actionable next steps to develop and better harness public health institutes and international networks.

Improving National Intelligence for Public Health Preparedness: a methodological approach to finding local multi-sector indicators for health security

The COVID-19 epidemic is the latest evidence of critical gaps in our collective ability to monitor country-level preparedness for health emergencies. The global frameworks that exist to strengthen core public health capacities lack coverage of several preparedness domains and do not provide mechanisms to interface with local intelligence. We designed and piloted a process, in collaboration with three National Public Health Institutes (NPHIs) in Ethiopia, Nigeria and Pakistan, to identify potential preparedness indicators that exist in a myriad of frameworks and tools in varying local institutions. Following a desk-based systematic search and expert consultations, indicators were extracted from existing national and subnational health security-relevant frameworks and prioritised in a multi-stakeholder two-round Delphi process. Eighty-six indicators in Ethiopia, 87 indicators in Nigeria and 51 indicators in Pakistan were assessed to be valid, relevant and feasible. From these, 14–16 indicators were prioritised in each of the three countries for consideration in monitoring and evaluation tools. Priority indicators consistently included private sector metrics, subnational capacities, availability and capacity for electronic surveillance, measures of timeliness for routine reporting, data quality scores and data related to internally displaced persons and returnees. NPHIs play an increasingly central role in health security and must have access to data needed to identify and respond rapidly to public health threats. Collecting and collating local sources of information may prove essential to addressing gaps; it is a necessary step towards improving preparedness and strengthening international health regulations compliance.

Using critical information to strengthen pandemic preparedness: the role of national public health agencies

COVID-19 has demonstrated that most countries' public health systems and capacities are insufficiently prepared to prevent a localised infectious disease outbreak from spreading. Strengthening national preparedness requires National Public Health Institutes (NPHIs), or their equivalent, to overcome practical challenges affecting timely access to, and use of, data that is critical to preparedness. Our situational analysis in collaboration with NPHIs in three countries-Ethiopia, Nigeria and Pakistan-characterises these challenges. Our findings indicate that NPHIs' role necessitates collection and analysis of data from multiple sources that do not routinely share data with public health authorities. Since initiating requests for access to new data sources can be a lengthy process, it is essential that NPHIs are routinely monitoring a broad set of priority indicators that are selected to reflect the country-specific context. NPHIs must also have the authority to be able to request rapid sharing of data from public and private sector organisations during health emergencies and to access additional human and financial resources during disease outbreaks. Finally, timely, transparent and informative communication of synthesised data from NPHIs will facilitate sustained data sharing with NPHIs from external organisations. These actions identified by our analysis will support the availability of robust information systems that allow relevant data to be collected, shared and analysed by NPHIs sufficiently rapidly to inform a timely local response to infectious disease outbreaks in the future.

Medical training for universal health coverage: a review of Cuba-South Africa collaboration

Achieving improvements in Universal Health Coverage will require a re-orientation of medical education towards a stronger focus on primary health care. Innovative medical curricula have been implemented in some countries, but in many low- and middle-income countries (LMICs), the emphasis remains focused on hospital and speciality services. Cuba has a long history of supporting LMICs and has made major contributions to African health care and medical training. A scheme for training South African students in Cuba was established 20 years ago and expanded more recently, with around 700 Cuban-trained graduates returning to South Africa each year from 2018 to 2022. The current strategy is to re-orientate and re-train these graduates in South African medical schools for up to 3 years as they are perceived to have inadequate skills. This negative narrative on Cuban-trained doctors in South Africa could be changed dramatically. They have highly appropriate skills in primary care and prevention and could provide much needed services to rural and urban under-served populations whilst gaining an orientation to the health problems of South Africa and strengthening their skills. Bilateral arrangements between South Africa and the United Kingdom are providing mechanisms to support such schemes. The Cuban approach to medical education may have lessons for many countries attempting to meet the challenges of Universal Health Coverage.

Building operational public health capacity through collaborative networks of National Public Health Institutes

The strengthening of public health systems internationally is integral to the improvement and protection of global population health. Essential public health functions and services are provided for by a range of organisations working together, often co-ordinated and strategically led by national Ministries of Health. Increasingly, however, National Public Health Institutes (NPHIs) are being developed to better integrate and support the delivery of these services. In this paper, we outline the role of NPHIs, analyse their advantages and shortcomings, and explore their potential to deliver enhanced public health through collaborative networking as well as partnership with WHO.

Cuban medical training for South African students: a mixed methods study

BACKGROUND

Achieving universal health care coverage will require greater investment in primary health care, particularly in rural and underserved populations in low and middle-income countries. South Africa has invested in training black students from disadvantaged backgrounds in Cuba and large numbers of these Cuban-trained students are now returning for final year and internship training in South Africa. There is controversy about the scheme, the quality and relevance of training received and the place of Cuban-trained doctors in the health care system. Exploring the experiences of Cuban- and South African-trained students, recent graduates and medical school faculty may help understand and resolve the current controversy.

METHODS

Using a mixed methods approach, in-depth interviews and a focus group discussion were held with deans of medical schools, senior faculty, and Cuban-trained and South African-trained students and recent graduates. An online structured questionnaire, adapted from the USA medical student survey, was developed and administered to Cuban- and South African-trained students and recent graduates.

RESULTS

South African students trained in Cuba have had beneficial experiences which orientate them towards primary health care and prevention. Their subsequent training in South Africa is intended to fill skill gaps related to TB, HIV and major trauma. However this training is ad hoc and variable in duration and demoralizing for some students. Cuban-trained students have stronger aspirations than those trained in South Africa to work in rural and underserved communities from which many of them are drawn.

CONCLUSION

Attempts to assimilate returning Cuban-trained students will require a reframing of the current negative narrative by focusing on positive aspects of their training, orientation towards primary care and public health, and their aspirations to work in rural and under-served urban areas. Cuban-trained doctors could be part of the solution to South Africa's health workforce problems.

Sustainable Development Goals (SDGs), and their implementation: A national global framework for health, development and equity needs a systems approach at every level

INTRODUCTION

The Sustainable Development Goals (SDGs) are a set of global goals for fair and sustainable health at every level: from planetary biosphere to local community. The aim is to end poverty, protect the planet and ensure that all people enjoy peace and prosperity, now and in the future.

SOURCES OF DATA

The UN has established web-sites to inform the implementation of the SDGs and an Inter-Agency and Expert Group on an Indicator Framework. We have searched for independent commentaries and analysis.

AREAS OF AGREEMENT

The goals represent a framework that is scientifically robust, and widely intuitive intended to build upon the progress established by the Millennium Development Goals (MDGs). There is a need for system wide strategic planning to integrate the economic, social and environmental dimensions into policy and actions.

AREAS OF CONTROVERSY

Many countries have yet to understand the difference between the MDGs and the SDGs, particularly their universality, the huge potential of new data methods to help with their implementation, and the systems thinking that is needed to deliver the vision. The danger is that individual goals may be prioritized without an understanding of the potential positive interactions between goals.

GROWING POINTS

There is an increasing understanding that sustainable development needs a paradigm shift in our understanding of the interaction between the real economy and quality of life. There would be many social, environmental and economic benefits in changing our current model.

AREAS TIMELY FOR DEVELOPING RESEARCH

We need to develop systems wide understanding of what supports a healthy environment and the art and science of making change.

Cost-effectiveness of community-based practitioner programmes in Ethiopia, Indonesia and Kenya

OBJECTIVE

To assess the cost-effectiveness of community-based practitioner programmes in Ethiopia, Indonesia and Kenya.

METHODS

Incremental cost-effectiveness ratios for the three programmes were estimated from a government perspective. Cost data were collected for 2012. Life years gained were estimated based on coverage of reproductive, maternal, neonatal and child health services. For Ethiopia and Kenya, estimates of coverage before and after the implementation of the programme were obtained from empirical studies. For Indonesia, coverage of health service interventions was estimated from routine data. We used the Lives Saved Tool to estimate the number of lives saved from changes in reproductive, maternal, neonatal and child health-service coverage. Gross domestic product per capita was used as the reference willingness-to-pay threshold value.

FINDINGS

The estimated incremental cost per life year gained was 82 international dollars ($)in Kenya, $999 in Ethiopia and $3396 in Indonesia. The results were most sensitive to uncertainty in the estimates of life-years gained. Based on the results of probabilistic sensitivity analysis, there was greater than 80% certainty that each programme was cost-effective.

CONCLUSION

Community-based approaches are likely to be cost-effective for delivery of some essential health interventions where community-based practitioners operate within an integrated team supported by the health system. Community-based practitioners may be most appropriate in rural poor communities that have limited access to more qualified health professionals. Further research is required to understand which programmatic design features are critical to effectiveness.

Discovery of ledipasvir (GS-5885): a potent, once-daily oral NS5A inhibitor for the treatment of hepatitis C virus infection

A new class of highly potent NS5A inhibitors with an unsymmetric benzimidazole-difluorofluorene-imidazole core and distal [2.2.1]azabicyclic ring system was discovered. Optimization of antiviral potency and pharmacokinetics led to the identification of 39 (ledipasvir, GS-5885). Compound 39 (GT1a replicon EC50 = 31 pM) has an extended plasma half-life of 37-45 h in healthy volunteers and produces a rapid >3 log viral load reduction in monotherapy at oral doses of 3 mg or greater with once-daily dosing in genotype 1a HCV-infected patients. 39 has been shown to be safe and efficacious, with SVR12 rates up to 100% when used in combination with direct-acting antivirals having complementary mechanisms.

Choice behavior and the accessibility of the reinforcer

In Experiment 1, matching of relative response rates to relative rates of reinforcement was obtained in concurrent variable-interval schedules when the absolute values of the two concurrent variable-interval schedules varied from 6 sec and 12 sec to 600 sec and 1200 sec. Increases in the duration of the changeover delay, however, produced decreases in the relative response rates and, consequently, some deviation from matching. In Experiment 2, matching of relative response rates to the relative duration of the reinforcer failed to occur when the equal variable-interval schedules arranging access to the two different reinforcer durations (1.5 and 6 sec) were varied in size from concurrent variable-interval 10-sec schedules to concurrent variable-interval 600-sec schedules.

A model for choice in simple concurrent and concurrent-chains schedules

Pigeons' responses in the presence of two concurrently available (initial-link) stimuli produced one of two different (terminal-link) stimuli. Entrance into the mutually exclusive terminal links was arranged by different and independent variable-interval schedules for each key, while responses during the mutually exclusive terminal-link stimuli produced a single food reinforcement according to indentical and independent variable-interval schedules. The pigeons emitted more initial-link responses on the key with the shorter average interreinforcement interval in the initial link. This difference in initial-link response rates varied directly with the difference between the average inter-reinforcement intervals of the initial-link schedules and decreased when the initial-link schedule with the longer average interreinforcement interval was followed by several consecutive food reinforcements on the variable-interval schedule in the terminal link on that key. These results are incompatible with previous formulations of choice behavior with the concurrent-chains procedure. A modified formulation with a multiplier for the overall rate of primary reinforcement obtained on each key provides a better description of choice. In addition, the new formulation applies to behavior in simple (concurrent) choice situations, an advantage not achieved by previous formulations.

Second-order schedules: discrimination of components

Pigeons were exposed to a series of second-order schedules in which the completion of a fixed number of fixed-interval components produced food. In Experiment 1, brief (2 sec) stimulus presentations occurred as each fixed-interval component was completed. During the brief-stimulus presentation terminating the last fixed-interval component, a response was required on a second key, the brief-stimulus key, to produce food. Responses on the brief-stimulus key before the last brief-stimulus presentation had no scheduled consequences, but served as a measure of the extent to which the final component was discriminated from preceding components. Whether there were one, two, four, or eight fixed-interval components, responses on the brief-stimulus key occurred during virtually every brief-stimulus presentation. In Experiment 2, an attempt was made to punish unnecessary responses on the brief-stimulus key, i.e., responses on the brief-stimulus key that occurred before the last component. None of the pigeons learned to withhold these responses, even though they produced a 15-sec timeout and loss of primary reinforcement. In Experiment 3, different key colors were associated with each component of a second-order schedule (a chain schedule). In contrast to Experiment 1, brief-stimulus key responses were confined to the last component. It was concluded that pigeons do not discriminate well between components of second-order schedules unless a unique exteroceptive cue is provided for each component. The relative discriminability of the components may account for the observed differences in initial-component response rates between comparable brief-stimulus, tandem, and chain schedules.

Reliability of urine collection pads for routine and metabolic biochemistry in infants and young children

The aim of our study was to evaluate whether specifically designed urine collection pads give reliable results for routine and metabolic biochemistry tests in paediatric urine. Urine collected by bag or clean-catch from infants and children <2 yrs without metabolic disorders was divided into two aliquots, one of which was added to a collection pad, incubated for 15 min at 37 degrees C (simulating in vivo collection conditions), then recovered by aspiration. Urine from adults with phaeochromocytoma and aqueous solutions of catecholamines were similarly treated. Routine, catecholamine, and metabolic analyses were performed on pad/non-pad aliquots. Selected metabolic analyses were also performed on pad/non-pad urine from patients with diagnosed inborn errors and urine containing added metabolites to simulate metabolic disorders. Routine tests (urea, electrolytes, creatinine, osmolality, calcium:creatinine, phosphate:creatinine, magnesium:creatinine, urate:creatinine [n = 32], oxalate:creatinine [n = 10]), and catecholamines (n = 12) showed good or acceptable concordance with no clinically significant pad/non-pad differences. Metabolic tests in infants and children without metabolic disorders all showed good pad/non-pad concordance for amino acids (n = 10), organic acids (n = 12), and glycosaminoglycans (n = 8). In patients with metabolic disorders (phenylketonuria [n = 1], homozygous/heterozygous cystinuria [n = 3], mucopolysaccharidoses II [n = 2] and III [n = 1], organic acid disorders [n = 6]) and urine containing added orotic acid to simulate urea cycle disorders, there was also good pad/non-pad concordance for diagnostic urinary metabolites. No extraneous organic acids were eluted from the pads. Sugar chromatography showed identical staining intensity in pad/non-pad samples. In conclusion, urine collection pads give reliable results for a wide range of routine and metabolic biochemistry tests in urine from paediatric patients.

Evaluation of antitumor properties of novel saframycin analogs in vitro and in vivo

Novel analogs of (-)-saframycin A are described. The analogs are shown to be potent inhibitors of the in vitro growth of several tumor cells in a broad panel and promising as leads for further optimization. The first in vivo studies in a solid tumor model (HCT-116) reveal potent antitumor activity with associated toxicity of daily administration.

Dysphagia management for progressive neurological conditions

This article discusses some of the issues surrounding dysphagia management for patients with progressive neurological conditions. It is important that health professionals are aware of the available options and that they consider patients' wishes to meet their nutritional needs.

Design and synthesis of beta-amino-alpha-hydroxy amide derivatives as inhibitors of MetAP2 and HUVEC growth

The rational design and synthesis of beta-amino-alpha-hydroxy amide derivatives as reversible inhibitors of methionine aminopeptidase-2 (MetAP2) with anti-proliferative activity against human umbilical vein endothelial cells (HUVECs) is described.

4-Aminoarylguanidine and 4-aminobenzamidine derivatives as potent and selective urokinase-type plasminogen activator inhibitors

The structure-based design of potent and selective urokinase-type plasminogen activator (uPA) inhibitors with 4-aminoarylamidine or 4-aminoarylguanidine S1 binding groups, is described.

School and neuropsychological performance of evacuated children in Kyiv 11 years after the Chornobyl disaster

This paper examines the cognitive and neuropsychological functioning of children who were in utero to age 15 months at the time of the Chornobyl disaster and were evacuated to Kyiv from the 30-kilometer zone surrounding the plant. Specifically, we compared 300 evacuee children at ages 10-12 with 300 non-evacuee Kyiv classmates on objective and subjective measures of attention, memory, and school performance. The evacuee children were not significantly different from their classmates on the objective measures (grades; Symbolic Relations subtest of the Detroit Test; forms 1 and 2 of the Visual Search and Attention Test; Benton Form A; Trails A; Underline the Words Test) or on most of the subjective measures (the attention subscale of the Child Behavior Checklist completed by mothers; the attention items of the Iowa Conners Teacher's Rating Scale; mother and child perceptions of school performance). The one exception was that 31.3% of evacuee mothers compared to 7.4% of classmate mothers indicated that their child had a memory problem. However, this subjective measure of memory problems was not significantly related to neuropsychological or school performance. No significant differences were found in comparisons of evacuees and classmates who were in utero at the time of the explosion, children from Pripyat vs. other villages in the 30-kilometer zone, and children manifesting greater generalized anxiety. For both groups, children with greater Chornobyl-focused anxiety performed significantly worse than children with less Chornobyl-focused anxiety on measures of attention. The results thus fail to confirm two previous reports that relatively more children from areas contaminated by radiation had cognitive deficits compared to controls. Possible reasons for the differences in findings among the studies are discussed.

Interventions for treating schistosomiasis haematobium

BACKGROUND

Schistosomiasis is a parasite that is carried by freshwater snails. There are two common forms, urinary schistosomiasis (which is considered in this review) and intestinal schistosomiasis.

OBJECTIVES

The objective of this review was to assess the effects of drugs for treatment of Schistosomiasis haematobium.

SEARCH STRATEGY

The Cochrane Infectious Diseases Group trials register, Medline and reference lists of articles were searched. The WHO Division of Control of Tropical Diseases was contacted.

SELECTION CRITERIA

Randomised trials of metrifonate or praziquantel or other drugs for treating Schistosomiasis haematobium.

DATA COLLECTION AND ANALYSIS

One reviewer assessed trial quality and extracted data, and this was checked by a review editor.

MAIN RESULTS

Five trials, all from Africa, were included. The quality of the trials was variable. There were no good randomised controlled trials of praziquantel single dose treatment versus current standard treatment with metrifonate of three doses of 10 milligrams per kilogram at two weekly intervals. Praziquantel at doses of 40 milligram per kilogram was more effective than single dose metrifonate 10 milligrams per kilogram (odds ratio 6.94, 95% confidence interval 4.85 to 9.92). In one trial of metrifonate compared with praziquantel, there was no difference demonstrated in a range of clinical outcomes including cessation of haematuria and proteinuria. Both drugs improved nutritional status and physical fitness.

REVIEWER'S CONCLUSIONS

Praziquantel (single dose) appears to be more effective than metrifonate (split dose) in terms of parasitological cure of Schistosomiasis haematobium, but the reinfection rate is high with both drugs.

Auditory brain stem responses in the mentally retarded: audiometric correlates

In previous reports we have suggested that the auditory brain-stem responses (ABRs) of adults with Down's syndrome exhibit two abnormalities unique to that population: a shortened central conduction time and an insensitivity of peak latencies to increases in stimulation rate. The current experiment assessed the possibility that these abnormalities were caused by hearing deficit rather than central auditory dysfunction. The ABRs of a group of adults with Down's syndrome were compared with those of a group of non-Down retarded and a control group of nonretarded adults. An audiometric examination consisting of pure-tone audiograms, tympanometry, and acoustic reflexes was given to all the retarded subjects. The incidence of serious hearing deficit in the Down's syndrome group was 73% compared to 22% in the non-Down retarded. Regardless of hearing status, the central conduction times in the Down group were shorter than in either of the other groups. The abnormal response to stimulation rate, however, was found to reflect high-frequency hearing loss and not central auditory dysfunction. The data suggest that a battery of objective tests including tympanometry, acoustic reflexes, and selected ABR measures may be useful in identifying hearing deficit in both Down-syndrome and non-Down retarded individuals.

Effects of chronic administration of mestranol on alpha and beta adrenergic responsiveness in female rats

Several alpha and beta adrenergic responses were studied in female rats after treatment with a low dose of the synthetic estrogen, mestranol (15 micrograms i.p. biweekly), for 4 to 6 weeks and compared with untreated controls. The response of blood pressure to exogenously administered norepinephrine was measured in conscious rats by means of an indwelling catheter in the femoral artery. Basal systolic blood pressure was not different between control and treated groups, or was any difference observed in peak systolic pressure after acute i.v. administration of l-norepinephrine in concentrations of 0.0625, 0.125, 0.250 and 0.625 micrograms. In contrast, the half-time of the blood pressure response was significantly prolonged after administration of the various concentrations of norepinephrine to mestranol-treated rats. The half-time of the pressor response observed in control animals administered 0.625 micrograms of norepinephrine was elicited in mestranol-treated animals by only 0.250 micrograms of norepinephrine. Analysis of the time course of the pressor response indicates that mestranol treatment altered the duration of the blood pressure increase without an apparent change in the onset of the pressor response. No differences between groups were observed in beta adrenergic responsiveness measured in terms of the isoproterenol-induced increase in either heart rate (beta-1 response) or water intake (beta-2 response). Finally, the contractile response of aortic rings from mestranol-treated rats to both l-norepinephrine (10(-9) to 10(-5) M) and l-phenylephrine (10(-8) to 10(-4) M) was significantly less than that of aortic rings from control rats. These data indicate, therefore, that in vivo cardiovascular responsiveness to norepinephrine does not reflect the attenuated vascular reactivity of isolated aortic rings. Insofar as the dominant feature of the in vivo adrenergic response appears to be prolongation of pressor action, the present study suggests that processes involved in the inactivation of circulating norepinephrine may be altered by chronic treatment with a low-dose of mestranol.

Binaural interaction in auditory brainstem responses of mentally retarded and nonretarded individuals

The short-latency auditory brainstem responses of institutionalized mentally retarded individuals (Down syndrome and unknown etiology) and nonretarded control persons were recorded. The results showed that retarded individuals differed in the clarity of initial auditory brainstem response waves (I and II). Down syndrome individuals had significantly smaller auditory brainstem response amplitudes (Waves II and III) when compared with retarded individuals of unknown etiology. Down syndrome individuals also had significantly shorter latencies (Waves III and V) and shorter interwave conduction times (III-I and V-I) when compared with retarded individuals of unknown etiology. Retarded individuals did not differ from control subjects when amplitudes of binaural auditory brainstem responses were compared to the computer summation of such responses evoked by left and right ear stimulation; however, there was evidence for a general binaural interaction effect.

Auditory brain stem response abnormalities in severely and profoundly retarded adults

The auditory brain stem evoked responses (ABRs) of two groups of retarded adults (Down's syndrome and retarded of unknown etiology) were compared with those of a group of non-retarded control subjects as a function of changes in stimulus repetition rate and stimulus intensity. The absence of ABRs at the highest stimulus intensity suggested profound hearing deficits in one or both ears of 4 Down's syndrome and 2 unknown-etiology subjects. Other abnormalities were noted in particular individuals of each group of retarded. In addition, the ABRs of the Down's group as a whole showed a significant pattern of abnormalities. The intervals between peaks I and II and III and IV were shorter than normal white the IV--V interval was prolonged. Wave V also showed abnormally small latency increases at fast click rates. The ABRs of the unknown-etiology group showed a shortened III--IV interval and a prolongation of the IV--V interval, but were otherwise not significantly different from the normal controls. These data suggest a high incidence of hearing loss in both diagnostic categories studies, and abnormal functioning of the auditory brain stem pathway in the Down's syndrome group as a whole.