Regulation of rhythmic activity in the stomatogastric ganglion of decapod crustaceans

Neuronal networks produce reliable functional output throughout the lifespan of an animal despite ceaseless molecular turnover and a constantly changing environment. The cellular and molecular mechanisms underlying the ability of these networks to maintain functional stability remain poorly understood. Central pattern generating circuits produce a stable, predictable rhythm, making them ideal candidates for studying mechanisms of activity maintenance. By identifying and characterizing the regulators of activity in small neuronal circuits, we not only obtain a clearer understanding of how neural activity is generated, but also arm ourselves with knowledge that may eventually be used to improve medical care for patients whose normal nervous system activity has been disrupted through trauma or disease. We utilize the pattern-generating pyloric circuit in the crustacean stomatogastric nervous system to investigate the general scientific question: How are specific aspects of rhythmic activity regulated in a small neuronal network? The first aim of this thesis poses this question in the context of a single neuron. We used a single-compartment model neuron database to investigate whether co-regulation of ionic conductances supports the maintenance of spike phase in rhythmically bursting “pacemaker” neurons. The second aim of the project extends the question to a network context. Through a combination of computational and electrophysiology studies, we investigated how the intrinsic membrane conductances of the pacemaker neuron influence its response to synaptic input within the framework of the Phase Resetting Curve (PRC). The third aim of the project further extends the question to a systems-level context. We examined how ambient temperatures affect the stability of the pyloric rhythm in the intact, behaving animal. The results of this work have furthered our understanding of the principles underlying the long-term stability of neuronal network function.Ph.D

Impact of service provision platforms on maternal and newborn health in conflict areas and their acceptability in Pakistan: a systematic review

Various models and strategies have been implemented over the years in different parts of the world to improve maternal and newborn health (MNH) in conflict affected areas. These strategies are based on specific needs and acceptability of local communities. This paper has undertaken a systematic review of global and local (Pakistan) information from conflict areas on platforms of health service provision in the last 10 years and information on acceptability from local stakeholders on effective models of service delivery; and drafted key recommendations for improving coverage of health services in conflict affected areas. The literature search revealed ten studies that described MNH service delivery platforms. The results from the systematic review showed that with utilisation of community outreach services, the greatest impacts were observed in skilled birth attendance and antenatal consultation rates. Facility level services, on the other hand, showed that labour room services for an internally displaced population (IDP) improved antenatal care coverage, contraceptive prevalence rate and maternal mortality. Consultative meetings and discussions conducted in Quetta and Peshawar (capitals of conflict affected provinces) with relevant stakeholders revealed that no systematic models of MNH service delivery, especially tailored for conflict areas, are available. During conflict, even previously available services and infrastructure suffered due to various barriers specific to times of conflict and unrest. A number of barriers that hinder MNH services were discussed. Suggestions for improving MNH services in conflict areas were also laid down by participants. The review identified some important steps that can be undertaken to mitigate the effects of conflict on MNH services, which include: improve provision and access to infrastructure and equipment; development and training of healthcare providers; and advocacy at different levels for free access to healthcare services and for the introduction of the programme model in existing healthcare system. The obligation is enormous, however, for a sustainable programme, it is important to work closely with both the IDP and host community, and collaborating with the government and non-government organisations

Impact of local terminology on the design of a community-based diagnostic and management algorithm for postpartum sepsis: Findings of formative research

Background: Postpartum sepsis is one of the leading causes of maternal mortality and morbidity in developing countries. This formative research elicits local terms used for postpartum illnesses and symptoms of postpartum sepsis with the aim of improving postpartum diagnosis and management in Pakistan.Methods: We conducted 34 in-depth interviews with recently delivered women (RDW), traditional birth attendants (TBAs), healthcare providers and family members of RDW from rural Sindh to explore local Sindhi terms used to describe postpartum sepsis and related symptoms. During interviews, all participants were asked to orally free list common symptoms of postpartum illnesses; those who were aware of the concept were asked to free list possible symptoms of postpartum sepsis. The responses were recorded by the interviewer. Free listing data were analyzed for frequency and salience.Results: Most participants, including TBAs, were not familiar with the concept of postpartum sepsis as a distinct disease or of a local term denoting the concept. Almost all could identify and report symptoms related to postpartum sepsis in the local language. Only physicians were able to recognize the term postpartum sepsis and related symptoms. Multiple local terms were used for a particular symptom; still others were used to denote gradations of severity. \u27Bukhar\u27 (fever) was the most commonly named symptom although it was often considered a normal part of puerperium. Many postpartum illnesses were related to the highly non-specific local term \u27kamzori\u27 (weakness).Conclusions: Better awareness about local terminology used in rural areas related to postpartum sepsis could improve communication, care-seeking patterns, diagnosis and management