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"Powell, Susan L"
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Perioperative outcomes after laparoscopic cholecystectomy in elderly patients: a systematic review and meta-analysis
2020
BackgroundLaparoscopic cholecystectomy is increasingly performed in an ever ageing population; however, the risks are poorly quantified. The study aims to review the current evidence to quantify further the postoperative risk of cholecystectomy in the elderly population compared to younger patients.MethodA systematic literature search of PubMed, EMBASE and the Cochrane Library databases were conducted including studies reporting laparoscopic cholecystectomy in the elderly population. A meta-analysis was reported in accordance with the recommendations of the Cochrane Library and PRISMA guidelines. Primary outcome was overall complications and secondary outcomes were conversion to open surgery, bile leaks, postoperative mortality and length of stay.ResultsThis review identified 99 studies incorporating 326,517 patients. Increasing age was significantly associated with increased rates of overall complications (OR 2.37, CI95% 2.00–2.78), major complication (OR 1.79, CI95% 1.45–2.20), risk of conversion to open cholecystectomy (OR 2.17, CI95% 1.84–2.55), risk of bile leaks (OR 1.50, CI95% 1.07–2.10), risk of postoperative mortality (OR 7.20, CI95% 4.41–11.73) and was significantly associated with increased length of stay (MD 2.21 days, CI95% 1.24–3.18).ConclusionPostoperative outcomes such as overall and major complications appear to be significantly higher in all age cut-offs in this meta-analysis. This study demonstrated there is a sevenfold increase in perioperative mortality which increases by tenfold in patients > 80 years old. This study appears to confirm preconceived suspicions of higher risks in elderly patients undergoing cholecystectomy and may aid treatment planning and informed consent.
Journal Article
A systematic review of transarterial embolization versus emergency surgery in treatment of major nonvariceal upper gastrointestinal bleeding
by
Powell, Susan
,
Atherton, Helen
,
Beggs, Andrew
in
Cardiovascular disease
,
Care and treatment
,
Diagnosis
2014
Emergency surgery or transarterial embolization (TAE) are options for the treatment of recurrent or refractory nonvariceal upper gastrointestinal bleeding. Surgery has the disadvantage of high rates of postoperative morbidity and mortality. Embolization has become more available and has the advantage of avoiding laparotomy in this often unfit and elderly population.
To carry out a systematic review and meta-analysis of all studies that have directly compared TAE with emergency surgery in the treatment of major upper gastrointestinal bleeding that has failed therapeutic upper gastrointestinal endoscopy.
A literature search of Ovid MEDLINE, Embase, and Google Scholar was performed. The primary outcomes were all-cause mortality and rates of rebleeding. The secondary outcomes were length of stay and postoperative complications.
A total of nine studies with 711 patients (347 who had embolization and 364 who had surgery) were analyzed. Patients in the TAE group were more likely to have ischemic heart disease (odds ratio [OR] =1.99; 95% confidence interval [CI]: 1.33, 2.98; P=0.0008; I (2)=67% [random effects model]) and be coagulopathic (pooled OR =2.23; 95% CI: 1.29, 3.87; P=0.004; I (2)=33% [fixed effects model]). Compared with TAE, surgery was associated with a lower risk of rebleeding (OR =0.41; 95% CI: 0.22, 0.77; P<0.0001; I (2)=55% [random effects]). There was no difference in mortality (OR =0.70; 95% CI: 0.48, 1.02; P=0.06; I (2)=44% [fixed effects]) between TAE and surgery.
When compared with surgery, TAE had a significant increased risk of rebleeding rates after TAE; however, there were no differences in mortality rates. These findings are subject to multiple sources of bias due to poor quality studies. These findings support the need for a well-designed clinical trial to ascertain which technique is superior.
Journal Article
Emergency surgery in the elderly: challenges and solutions
by
Powell, Susan
,
Torrance, Andrew
,
Griffiths, Ewen
in
Activities of daily living
,
Age discrimination
,
Age groups
2015
Elderly patients frequently present with surgical emergencies to health care providers, and outcomes in this group of patients remain poor. Contributing factors include frailty, preexisting comorbidity, polypharmacy, delayed diagnosis, and lack of timely and consultant-led treatment. In this review, we address common emergency surgical presentations in the elderly and highlight the specific challenges in caring for these patients. We summarize 20 years of reports by various medical bodies that have aimed to improve the care of these patients. To improve morbidity and mortality, several aspects of care need to be addressed. These include accurate and timely preoperative assessment to identify treatable pathology and, where possible, to consider and correct age-specific disease processes. Identification of patients in whom treatment would be futile or associated with high risk is needed to avoid unnecessary interventions and to give patients and carers realistic expectations. The use of multidisciplinary teams to identify common postoperative complications and age-specific syndromes is paramount. Prevention of complications is preferable to rescue treatment due to the high proportion of patients who fail to recover from adverse events. Even with successful surgical treatment, long-term functional decline and increased dependency are common. More research into emergency surgery in the elderly is needed to improve care for this growing group of vulnerable patients.
Journal Article
Intravenous Cyclosporine Activates Afferent and Efferent Renal Nerves and Causes Sodium Retention in Innervated Kidneys in Rats
by
Moss, Nicholas G.
,
Falk, Ronald J.
,
Powell, Susan L.
in
Afferent nerves
,
Afferent Pathways
,
Animals
1985
The effect of acute intravenous infusion of cyclosporine (10 mg/kg) on efferent renal and genitofemoral nerve activity and afferent renal nerve activity was studied in anesthetized rats. All animals were studied after unilateral renal denervation and extracellular fluid volume expansion. Activity of both efferent sympathetic nerves was increased significantly by cyclosporine infusion (renal, 69%; genitofemoral, 60%). Afferent renal nerve activity was increased 82% after cyclosporine (P < 0.05). Urine flow rate and both absolute and fractional sodium excretion from the innervated kidney were reduced 50% after cyclosporine infusion (P < 0.01). Absolute and fractional sodium excretion from the denervated kidney were significantly increased after cyclosporine. Infusion of vehicle had no significant effect on any measured variable in innervated or denervated kidneys. These studies demonstrate the capacity of cyclosporine to increase efferent sympathetic nerve activity and afferent nerve activity. It is also shown that sodium retention resulting from acute infusion of cyclosporine can be attributed to the increase in efferent renal nerve activity.
Journal Article
Mapping the Global Emergence of Batrachochytrium dendrobatidis, the Amphibian Chytrid Fungus
by
Aanensen, David M.
,
Walker, Susan F.
,
Olson, Deanna H.
in
Adaptive management
,
Amphibians - microbiology
,
Animals
2013
The rapid worldwide emergence of the amphibian pathogen Batrachochytrium dendrobatidis (Bd) is having a profound negative impact on biodiversity. However, global research efforts are fragmented and an overarching synthesis of global infection data is lacking. Here, we provide results from a community tool for the compilation of worldwide Bd presence and report on the analyses of data collated over a four-year period. Using this online database, we analysed: 1) spatial and taxonomic patterns of infection, including amphibian families that appear over- and under-infected; 2) relationships between Bd occurrence and declining amphibian species, including associations among Bd occurrence, species richness, and enigmatic population declines; and 3) patterns of environmental correlates with Bd, including climate metrics for all species combined and three families (Hylidae, Bufonidae, Ranidae) separately, at both a global scale and regional (U.S.A.) scale. These associations provide new insights for downscaled hypothesis testing. The pathogen has been detected in 52 of 82 countries in which sampling was reported, and it has been detected in 516 of 1240 (42%) amphibian species. We show that detected Bd infections are related to amphibian biodiversity and locations experiencing rapid enigmatic declines, supporting the hypothesis that greater complexity of amphibian communities increases the likelihood of emergence of infection and transmission of Bd. Using a global model including all sampled species, the odds of Bd detection decreased with increasing temperature range at a site. Further consideration of temperature range, rather than maximum or minimum temperatures, may provide new insights into Bd-host ecology. Whereas caution is necessary when interpreting such a broad global dataset, the use of our pathogen database is helping to inform studies of the epidemiology of Bd, as well as enabling regional, national, and international prioritization of conservation efforts. We provide recommendations for adaptive management to enhance the database utility and relevance.
Journal Article
Inequality in early childhood: risk and protective factors for early child development
by
Walker, Susan P
,
Hamadani, Jena D
,
Gardner, Julie M Meeks
in
Biological and medical sciences
,
brain
,
breast feeding
2011
Inequality between and within populations has origins in adverse early experiences. Developmental neuroscience shows how early biological and psychosocial experiences affect brain development. We previously identified inadequate cognitive stimulation, stunting, iodine deficiency, and iron-deficiency anaemia as key risks that prevent millions of young children from attaining their developmental potential. Recent research emphasises the importance of these risks, strengthens the evidence for other risk factors including intrauterine growth restriction, malaria, lead exposure, HIV infection, maternal depression, institutionalisation, and exposure to societal violence, and identifies protective factors such as breastfeeding and maternal education. Evidence on risks resulting from prenatal maternal nutrition, maternal stress, and families affected with HIV is emerging. Interventions are urgently needed to reduce children's risk exposure and to promote development in affected children. Our goal is to provide information to help the setting of priorities for early child development programmes and policies to benefit the world's poorest children and reduce persistent inequalities.
Journal Article
Antipurinergic Therapy Corrects the Autism-Like Features in the Poly(IC) Mouse Model
2013
Autism spectrum disorders (ASDs) are caused by both genetic and environmental factors. Mitochondria act to connect genes and environment by regulating gene-encoded metabolic networks according to changes in the chemistry of the cell and its environment. Mitochondrial ATP and other metabolites are mitokines-signaling molecules made in mitochondria-that undergo regulated release from cells to communicate cellular health and danger to neighboring cells via purinergic signaling. The role of purinergic signaling has not yet been explored in autism spectrum disorders.
We used the maternal immune activation (MIA) mouse model of gestational poly(IC) exposure and treatment with the non-selective purinergic antagonist suramin to test the role of purinergic signaling in C57BL/6J mice.
We found that antipurinergic therapy (APT) corrected 16 multisystem abnormalities that defined the ASD-like phenotype in this model. These included correction of the core social deficits and sensorimotor coordination abnormalities, prevention of cerebellar Purkinje cell loss, correction of the ultrastructural synaptic dysmorphology, and correction of the hypothermia, metabolic, mitochondrial, P2Y2 and P2X7 purinergic receptor expression, and ERK1/2 and CAMKII signal transduction abnormalities.
Hyperpurinergia is a fundamental and treatable feature of the multisystem abnormalities in the poly(IC) mouse model of autism spectrum disorders. Antipurinergic therapy provides a new tool for refining current concepts of pathogenesis in autism and related spectrum disorders, and represents a fresh path forward for new drug development.
Journal Article
Child Development 1: Inequality in early childhood: risk and protective factors for early child development
by
Walker, Susan P
,
Hamadani, Jena D
,
Gardner, Julie M Meeks
in
Babies
,
Breast feeding
,
Child development
2011
Inequality between and within populations has origins in adverse early experiences. Developmental neuroscience shows how early biological and psychosocial experiences affect brain development. We previously identified inadequate cognitive stimulation, stunting, iodine deficiency, and iron-deficiency anaemia as key risks that prevent millions of young children from attaining their developmental potential. Recent research emphasises the importance of these risks, strengthens the evidence for other risk factors including intrauterine growth restriction, malaria, lead exposure, HIV infection, maternal depression, institutionalisation, and exposure to societal violence, and identifies protective factors such as breastfeeding and maternal education. Evidence on risks resulting from prenatal maternal nutrition, maternal stress, and families affected with HIV is emerging. Interventions are urgently needed to reduce children's risk exposure and to promote development in affected children. Our goal is to provide information to help the setting of priorities for early child development programmes and policies to benefit the world's poorest children and reduce persistent inequalities. [PUBLICATION ABSTRACT]
Journal Article
Patient-Reported Outcomes after Monitoring, Surgery, or Radiotherapy for Prostate Cancer
2016
The choice of treatment for PSA-detected, localized prostate cancer is influenced by effects of the interventions on quality of life. In the ProtecT trial, patterns of side-effect severity, improvement, and decline in urinary, sexual, and bowel function differed among the treatments.
As reported in a companion article in the
Journal,
the U.K. National Institute for Health Research–supported Prostate Testing for Cancer and Treatment (ProtecT) trial has shown no significant difference in prostate-cancer–specific mortality or all-cause mortality among men with prostate cancer detected by prostate-specific antigen (PSA) testing who were randomly assigned to radical prostatectomy, active monitoring (a surveillance strategy), or radical conformal radiotherapy with neoadjuvant hormonal therapy, at a median of 10 years of follow-up; however, the ProtecT trial has shown higher rates of metastases and disease progression among men in the active-monitoring group than among men in the radical-treatment groups. . . .
Journal Article
The IgA in milk induced by SARS-CoV-2 infection is comprised of mainly secretory antibody that is neutralizing and highly durable over time
2022
Approximately 10% of infants infected with SARS-CoV-2 will experience COVID-19 illness requiring advanced care. A potential mechanism to protect this population is passive immunization via the milk of a previously infected person. We and others have reported on the presence of SARS-CoV-2-specific antibodies in human milk. We now report the prevalence of SARS-CoV-2 IgA in the milk of 74 COVID-19-recovered participants, and find that 89% of samples are positive for Spike-specific IgA. In a subset of these samples, 95% exhibited robust IgA activity as determined by endpoint binding titer, with 50% considered high-titer. These IgA-positive samples were also positive for Spike-specific secretory antibody. Levels of IgA antibodies and secretory antibodies were shown to be strongly positively correlated. The secretory IgA response was dominant among the milk samples tested compared to the IgG response, which was present in 75% of samples and found to be of high-titer in only 13% of cases. Our IgA durability analysis using 28 paired samples, obtained 4–6 weeks and 4–10 months after infection, found that all samples exhibited persistently significant Spike-specific IgA, with 43% of donors exhibiting increasing IgA titers over time. Finally, COVID-19 and pre-pandemic control milk samples were tested for the presence of neutralizing antibodies; 6 of 8 COVID-19 samples exhibited neutralization of Spike-pseudotyped VSV (IC 50 range, 2.39–89.4ug/mL) compared to 1 of 8 controls. IgA binding and neutralization capacities were found to be strongly positively correlated. These data are highly relevant to public health, not only in terms of the protective capacity of these antibodies for breastfed infants, but also for the potential use of such antibodies as a COVID-19 therapeutic, given that secretory IgA is highly in all mucosal compartments.
Journal Article