The Effectiveness and Cost-Effectiveness of Community Diagnostic Centres: A Rapid Review.

Objectives: To examine the effectiveness of community diagnostic centres as a potential solution to increasing capacity and reducing pressure on secondary care in the UK. Methods: A comprehensive search for relevant primary studies was conducted in a range of electronic sources in August 2022. Screening and critical appraisal were undertaken by two independent reviewers. There were no geographical restrictions or limits to year of publication. A narrative synthesis approach was used to analyse data and present findings. Results: Twenty primary studies evaluating twelve individual diagnostic centres were included. Most studies were specific to cancer diagnosis and evaluated diagnostic centres located within hospitals. The evidence of effectiveness appeared mixed. There is evidence to suggest diagnostic centres can reduce various waiting times and reduce pressure on secondary care. However, cost-effectiveness may depend on whether the diagnostic centre is running at full capacity. Most included studies used weak methodologies that may be inadequate to infer effectiveness. Conclusion: Further well-designed, quality research is needed to better understand the effectiveness and cost-effectiveness of community diagnostic centres.

Phencyclidine-like abuse liability and psychosis-like neurocognitive effects of novel arylcyclohexylamine drugs of abuse in rodents.

Abuse of novel arylcyclohexylamines (ACX) poses risks for toxicities including adverse neurocognitive effects. In vivo effects of ring-substituted analogs of phencyclidine (PCP), eticyclidine (PCE), and ketamine are understudied. Adult male NIH Swiss mice were used to assess locomotor effects of PCP and its 3-OH, 3-MeO, 3-Cl and 4-MeO analogs; PCE and its 3-OH and 3-MeO analogs; and ketamine and its deschloro and 2F-deschloro analogs, in comparison to those of methamphetamine (METH), 3,4-methylenedioxymethamphetamine (MDMA), and two benzofuran analogs of MDMA. PCP-like interoceptive effects for all of these ACXs were determined using a food-reinforced drug discrimination procedure in adult male Sprague Dawley rats. A novel operant assay of rule-governed behavior incorporating aspects of attentional set-shifting was used to profile psychosis-like neurocognitive effects of PCP and 3-Cl-PCP in rats, in comparison to cocaine and morphine. PCP-like ACXs were more effective locomotor stimulants than the amphetamines, PCE-like ACXs were as effective as the amphetamines, and ketamine-like ACXs were less effective than the amphetamines. Addition of -Cl, -OH, or -OMe at the 3-position on the aromatic ring did not impact locomotor effectiveness, but addition of -OMe at the 4-position reduced locomotor effectiveness. Lethal effects were induced by drugs with -OH at the 3-position or -OMe at the 3- or 4-position. All novel ACXs substituted at least partially for PCP, and PCP and 3-Cl-PCP elicited dose-dependent psychosis-like neurocognitive deficits in the rule governed behavior task not observed with cocaine or morphine. Novel ACXs exhibit substantial abuse liability and toxicities not necessarily observed with their parent drugs. Significance Statement Novel arylcyclohexylamine analogs of PCP, PCE and ketamine are appearing on the illicit market, and abuse of these drugs poses risks for toxicities including adverse neurocognitive effects. These studies demonstrate that the novel ACXs exhibit PCP-like abuse liability in the drug discrimination assay, elicit varied locomotor stimulant and lethal effects in mice, and induce psychosis-like neurocognitive effects in rats.

Neurological observations in infants, children and young people: part one.

Caring for infants, children and young people with an acquired brain injury (ABI) can be challenging due to their developing brain and reliance on parents and caregivers. It is essential that children's nurses are able to perform effective neurological observations, because these can identify deterioration and inform the management of patients with an ABI. This is the first of two articles that aim to encourage accuracy and consistency when undertaking neurological observations in infants, children and young people with an ABI to optimise their care. This first article details the pathophysiology, types and causes of ABIs and explains the potential complications that can occur following such injuries.

Neurological observations in infants, children and young people: part two.

Neurological observations are a vital part of the assessment of infants, children and young people with a suspected or confirmed acquired brain injury (ABI). They are designed to identify neurological deterioration and inform the management of ABIs. Children's nurses may perform many of these neurological observations, including by using tools such as the AVPU scale, the Glasgow Coma Scale, pupillary response and limb assessment. This is the second of two articles that aim to encourage accuracy and consistency when performing neurological observations in infants, children and young people with a suspected or confirmed ABI to optimise their care. The article explains how to undertake various elements of a neurological assessment, how often to perform neurological observations, when to escalate concerns and why it is important to use family-centred care.

Intrapleural tissue plasminogen activator and deoxyribonuclease administered concurrently and once daily for complex parapneumonic pleural effusion and empyema.

BACKGROUND: Pleural infection is life-threatening and increasingly prevalent. In addition to usual care, twice-daily, separate administration of tissue plasminogen activator and deoxyribonuclease (tPA-DNase) reduces radiological pleural opacity with lower surgical referral rates. AIMS: This retrospective cohort study examines the use of once-daily, concurrent administration of tPA-DNase for complex parapneumonic pleural effusion and empyema. METHODS: Patients with pleural infection who received intrapleural tPA-DNase between October 2014 and July 2020 at Logan Hospital, where it is given concurrently and once-daily as salvage therapy, were retrospectively identified. Radiographic opacification, inflammatory markers, clinical response and complications were examined. RESULTS: Thirty-one patients were identified. Mean age was 48.8 years (standard deviation [SD], 17.2). Median tPA-DNase administration was 3 (interquartile range [IQR], 2-3). Chest x-ray pleural opacity decreased significantly (P = 0.047) from a median of 39.6% (IQR, 28.8-65.7%) to 9.7% (IQR, 2.5-23.2%), a median relative reduction of 75.5% (IQR, 47.7-93.9%). White cell count and C-reactive protein improved significantly (P = 0.002 and P = 0.032, respectively) from a median of 16.3 × 109 /L (IQR, 11.8-20.6 × 109 /L) to 9.9 × 109 /L (IQR, 8.0-12.3 × 109 /L) and 311.0 mg/L (IQR, 218.8-374.0 mg/L) to 69.0 mg/L (IQR, 36.0-118.0 mg/L), respectively. No patients experienced significant bleeding or died. Five patients (16.1%) were referred for surgery. CONCLUSION: This is pilot evidence that a practical regimen of concurrent, once-daily intrapleural tPA-DNase improved pleural opacification and inflammatory markers without bleeding or mortality. The surgical referral rate was higher than in studies assessing twice-daily administration, though the validity of this outcome as a measure of treatment success is limited, and further studies are needed to assess the optimal dose and frequency of intrapleural therapy and indications for surgical referral.

"Me and 'that' machine": the lived experiences of people with neuromuscular disorders using non-invasive ventilation.

PURPOSE: Neuromuscular disorders (NMD) encompasses a wide range of conditions, with respiratory weakness a common feature. Respiratory care can involve non-invasive ventilation (NIV) resulting in fewer hospital admissions, a lower mortality rate and improved quality of life. The aim of this study was to explore the 'lived experience' of NIV by people with NMD. METHODS: Interpretive Phenomenological Analysis (IPA) with semi-structured, face to face interviews with 11 people with NMD, using bi-level positive airway pressure for NIV for more than 12 months. RESULTS: Three themes were interpreted: (i) Alive, with a life; (ii) Me and 'that' machine; and (iii) Precariousness of this life. NIV enabled hope, independence and the opportunity to explore previously perceived unattainable life experiences. Yet, participants felt dependent on the machine. Furthermore, practical considerations and fear of NIV failure created a sense of precariousness to life and a reframing of personal identity. CONCLUSION: The findings highlight the broad ranging positive and negative effects that may occur for people with NMD when using this important therapy. Ongoing non-judgemental support and empathy are required from health professionals as the use of NIV challenged concepts such as 'living life well' for people with NMD. IMPLICATIONS FOR REHABILITATIONNeuromuscular disorders may result in respiratory weakness requiring non-invasive ventilation (NIV).When prescribed early, NIV can results in fewer hospital admissions, a lower mortality rate and improved quality of life.The relationship of people with NMD with their NIV machine is complex and impacts on and requires adjustment to their identity.NIV users acknowledged that NIV provided hope but simultaneously recognised the precariousness of NIV on their life.In order to better support people with NMD healthcare professionals need to better understand how the physical, psychological and social implications of NIV affect an individual's life.

Understanding beliefs, preferences and actions amongst potential body donors.

Body donation is a prosocial act providing a unique learning experience to students, ultimately impacting on patient care and science. With an increasing number of training professionals, there is an increasing need for body donors, yet little is understood about donors' beliefs and preferences. A four-center study aimed to understand donors' perceptions, 843 responses highlighted a significant relationship between completing a body donor consent form and being both an organ donor and having ever donated blood (p < 0.01). In exploring donor intentions, 69% had been considering donation for fewer than five years, 40% knew another body donor, and 27% had a family member or friend currently registered. Of those who had requested donor information packs, 97% had completed body donation consent forms. Of these, 92% had not selected any time restriction for their donation and 96% had consented to images being taken. Almost all (98%) were aware that their donation might not be accepted. Donors' motives highlighted a wish to: improve education, improve health care, advance science, and contribute to the greater good. A bimodal response was observed with body donation being used to save relatives money and inconvenience. Donors felt comfortable with their bodies being used by medical, dental, and allied health professionals; however, donors were less comfortable with their bodies being used by other groups. Only 57% were comfortable with artists, beauticians and yoga teachers using their remains. Understanding donors' motivations and decision-making process is vital to ensure resources for future and to meet any changing requirements of both donors and those studying them.

The NHS in Northern Ireland Post-Brexit: the Legal Position on Product Supply.

The UK left the European Union's single market on 1 January 2021. A Withdrawal Agreement made special provision for Northern Ireland. However, 'grace periods' concerning supply of goods were agreed, delaying full application of the new rules. The Northern Ireland NHS is heavily reliant on supplies from Great Britain. If these supplies are disrupted, the quality of care offered to patients will diminish. This article shows the legal details of applicable law once the 'grace periods', which are currently securing supply, cease to apply. It reveals significant costs and uncertainties associated with supply of products to the NHS in Northern Ireland. The direction of travel, unless something changes, is that new products will reach patients later than in Great Britain, and there is a real possibility that some products become difficult or impossible for the NHS in Northern Ireland to source. The result will be reduced quality of patient care.

What was the impact of a global pandemic (COVID-19) lockdown period on experiences within an eating disorder service? A service evaluation of the views of patients, parents/carers and staff.

BACKGROUND: The World Health Organization declared the outbreak of COVID-19 as a global pandemic on the 11th March 2020. As a result, the UK Government imposed severe restrictions on working and social contact as part of "lockdown." Whilst the full extent of the pandemic's impact on eating disorder patients is unknown, the literature suggests that patients with pre-existing mental illness may be more vulnerable to the mental health impacts. In addition, the restrictions greatly reduced the access to mental health services and presented new challenges to service delivery. A service evaluation was carried out to explore how the COVID-19 global pandemic changed service provision in a young person's eating disorder service and how this affected patient, family and staff experiences. METHODS: An audit was carried out to explore how the lockdown period had impacted referrals and service delivery. Quantitative data was collected in an online survey and qualitative data was collected in two formats: open ended answers as part of the online survey and open-ended focus groups, structured using narrative enquiry. The 43 participants consisted of 12 patients, 19 parents/carers, and 12 staff members. Patients were under the age of 18 and had a diagnosis of an eating disorder. RESULTS: COVID-19 and lockdown increased the pressure on the service and changed service provision significantly. This has impacted the relational experiences for patients and their carers and staff have been faced with new challenges. Patients, parents/carers and staff all preferred face-to-face appointments over virtual options. There was no difference in service satisfaction before and during COVID-19. CONCLUSIONS: It is possible to provide an eating disorder service in lockdown restrictions that patients and parents report high satisfaction with. Providing face-to-face appointments at the beginning of treatment and including families in the planning should be prioritised. Staff support is crucial to be able to continue delivering high quality services. The key themes are identified, and clinical recommendations are made to guide service delivery.

Genetic diversity and shedding profiles for Cryptosporidium parvum in adult cattle and their calves.

Cryptosporidiosis is an important disease in neonatal calves, causing watery diarrhoea, loss of appetite, and production losses. Dehydration from diarrhoea often results in the calf requiring rehydration or veterinary treatment to prevent calf mortality. Transmission of Cryptosporidium to calves still has some major knowledge gaps, such as the initial source of oocysts ingested by calves and how these oocysts can persist between calving periods. Some studies have examined the role of adult cattle in the transmission of Cryptosporidium oocysts, although these have yielded inconclusive results. In this study, highly sensitive oocyst extraction from faeces and detection techniques, sensitive to 5 oocysts per gram using a 50 g sample, were used to genotype faecal samples from adult cattle and their calves to determine if adult cattle could be a source of Cryptosporidium infection for their calves. On a dairy farm, faecal samples from adult cattle were collected twice per week for 0-3 weeks before calving and from their calves three times per week until they reached 3 weeks of age followed by twice per week until they reached 6 weeks of age. On a beef farm, samples were collected from both adults and calves at a single time point. Faecal samples were examined to compare species and multilocus genotypes of Cryptosporidium parvum. Results show that C. parvum was the most prevalent species on both the dairy and beef farms. The calves within each herd appear to have one predominant single multilocus genotype, whereas adult cattle have multiple distinct genotypes. Adult cattle on the dairy farm, tested before calving, in the majority of cases had a multilocus genotype that is different from that detected in their calves. On the beef farm, where samples were taken at the same time, the majority of adult cattle matched the multilocus genotype of their calves. This study shows that adult cattle display a higher diversity of C. parvum genotypes on both farms compared to the calves. The data also represent a detailed longitudinal prevalence study of the shedding profiles and genotype of Cryptosporidium parasites detected in dairy calves from birth to 6 weeks of age.

Long-term production effects of clinical cryptosporidiosis in neonatal calves.

Cryptosporidiosis can have a devastating effect in neonatal calves, resulting in diarrhoea, dehydration and, in severe cases, death of the animal. The disease is caused by Cryptosporidium spp. and is one of the most common causes of calf enteritis in the UK. The parasite is very difficult to remove from the farm, as the oocysts have a tough outer wall which enables the parasite to survive for several months in moist temperate environmental conditions and it is difficult to kill oocysts with common disinfectants used on a farm. If appropriate management practises are applied, the disease is usually self-limiting and most calves will recover. It has been shown, in studies with children and in lambs, that severe clinical cryptosporidiosis can result in long-term growth and cognitive impairment compared with individuals with no obvious signs of the disease. This study measured the long-term growth rate of beef calves on farm by comparing groups of animals that had suffered differing degrees of clinical severity of cryptosporidiosis as neonates. A group of 27 beef calves were enrolled in the study and monitored from birth to 6 months of age. The calves were scored for severity of cryptosporidiosis and weighed at regular intervals. The average difference in weight gain, at 6 months, between a group of calves that had severe cryptosporidiosis as neonates and a group of calves with no clinical signs of infection was 34 kg. Those calves that had experienced severe cryptosporidiosis as neonates showed a significantly reduced live weight gain compared with those calves showing no clinical signs of infection (P = 0.034). Therefore, the impact of severe cryptosporidiosis in neonatal calves has longer term effects on weight gain and production efficiency, resulting in the parasite having a greater impact on cattle production than previously thought.

Cryptosporidium Prevalence in Calves and Geese Co-Grazing on Four Livestock Farms Surrounding Two Reservoirs Supplying Public Water to Mainland Orkney, Scotland.

The parasite Cryptosporidium parvum represents a threat to livestock health and production, water quality and public health. Cattle are known to be significant reservoirs of C. parvum, but transmission routes are complex and recent studies have implicated the potential role of wildlife in parasite transmission to cattle and water sources. On the Orkney Isles, high densities of Greylag geese (Anser anser) cause widespread faecal contamination of cattle pastures, where cryptosporidiosis is known to be the main cause of neonatal calf diarrhoea and Cryptosporidium contamination frequently occurs in two reservoirs supplying Mainland Orkney's public water. This study aimed to determine the Cryptosporidium species and subtypes present in geese and calves co-grazing on four farms surrounding two reservoirs on Mainland Orkney. Results indicated a high level of C. parvum prevalence in calves, geese and water samples. gp60 analysis illustrated that higher genotypic diversity was present in the goose population compared with calves, but did not yield sequence results for any of the water samples. It can be concluded that the high levels of C. parvum evident in calves, geese and water samples tested represents a significant risk to water quality and public health.

CAPE for measuring callous-unemotional traits in disadvantaged families: a cross-sectional validation study.

Background: Callous-unemotional (CU) traits are important for designating a distinct subgroup of children and adolescents with behaviour problems.  As a result, CU traits are now used to form the specifier "with Limited Prosocial Emotions" that is part of the diagnostic criteria for the Conduct Disorder in the Diagnostic and Statistical Manual of Mental Disorders 5 th Edition (DSM-5) and International Classification of Diseases 11 th Revision (ICD-11).  Given this inclusion in major classification systems, it is important to develop and test methods for assessing these traits that can be used in clinical settings.  The present study aimed to validate a clinician rating of CU traits, the Clinical Assessment of Prosocial Emotions, Version 1.1 (CAPE 1.1), in a sample of hard-to-reach families referred to a government program designed to prevent the development of behaviour problems in high risk families. Methods: Clinical ratings of children were obtained from 34 families of children ages 5 to 18 (M=13.5; SD=3.2). The ratings on the CAPE 1.1 were based on interviews with both parent and child. Results: Of the sample, 21% (100% male) met the diagnostic cut-off for the specifier according to the CAPE 1.1, and CAPE 1.1 scores were associated with parent ratings of CU traits, psychopathic traits, and externalising behaviours. CAPE 1.1 ratings were also associated with risk for violence obtained from case files.  Conclusions: These findings provide preliminary evidence for the validity of the CAPE 1.1 as clinician rated measure of CU traits.

Detection of potentially human infectious assemblages of Giardia duodenalis in fecal samples from beef and dairy cattle in Scotland.

This study aimed to determine the prevalence and assemblages of Giardia duodenalis present in Scottish beef and dairy cattle at different ages, to try to ascertain if cattle could play a role in the spread of zoonotic assemblages of Giardia. A total of 388 fecal samples (128 beef and 253 dairy, seven of unknown breed) were collected from 19 farms in Scotland. Samples were sub-divided by host age, 1, 2, 3, 4, 5 and 6, 7-24 and ⩾25 weeks. DNA was extracted and tested by PCR to detect G. duodenalis DNA. Of the 388 samples, 126 tested positive, giving an overall prevalence of 32.5%, with positive samples being observed in all age groups tested. The prevalence in dairy cattle was 44.7% (113/235), which was significantly higher (P < 0.001) than the prevalence in beef cattle 10.1% (13/128). Sequence analysis demonstrated the presence of assemblage E (77.2%, sequence types E-S1-E-S5), assemblage B (18.2%) and assemblage A (sub-assemblages AI-AII) (4.6%). These data demonstrate that G. duodenalis is found routinely in both dairy and beef cattle throughout Scotland; the presence of assemblages A and B also indicates that cattle may play a role in the spread of potentially zoonotic assemblages of Giardia.

Learning anatomy through Thiel- vs. formalin-embalmed cadavers: Student perceptions of embalming methods and effect on functional anatomy knowledge.

Thiel-embalmed cadavers, which have been adopted for use in anatomy teaching in relatively few universities, show greater flexibility and color retention compared to formalin-embalmed cadavers, properties which might be considered advantageous for anatomy teaching. This study aimed to investigate student attitudes toward the dissection experience with Thiel- compared to formalin/ethanol-embalmed cadavers. It also aimed to determine if one embalming method is more advantageous in terms of learning functional anatomy through the comparison of student anterior forearm functional anatomy knowledge. Student opinions and functional anatomy knowledge were obtained through use of a questionnaire from students at two medical schools, one using Thiel-, and one using more traditional formalin/ethanol-embalmed cadavers. Both the Thiel group and the formalin group of students were surveyed shortly after completing an anterior forearm dissection session. Significant differences (P-values <0.01) in some attitudes were found toward the dissection experience between cohorts using Thiel- vs. formalin-embalmed cadavers. The Thiel group of students felt more confident about recognizing anatomy in the living individual, found it easier to identify and dissect anatomical structures, and indicated more active exploration of functional anatomy due to the retained flexibility of the cadaver. However, on testing, no significant difference in functional anatomy knowledge was found between the two cohorts. Overall, although Thiel embalming may provide an advantageous learning experience in some investigated areas, more research needs to be carried out, especially to establish whether student perception is based on reality, at least in terms of structure identification. Anat Sci Educ 11: 166-174. © 2017 American Association of Anatomists.

Targeted mitochondrial therapy using MitoQ shows equivalent renoprotection to angiotensin converting enzyme inhibition but no combined synergy in diabetes.

Mitochondrial dysfunction is a pathological mediator of diabetic kidney disease (DKD). Our objective was to test the mitochondrially targeted agent, MitoQ, alone and in combination with first line therapy for DKD. Intervention therapies (i) vehicle (D); (ii) MitoQ (DMitoQ;0.6 mg/kg/day); (iii) Ramipril (DRam;3 mg/kg/day) or (iv) combination (DCoAd) were administered to male diabetic db/db mice for 12 weeks (n = 11-13/group). Non-diabetic (C) db/m mice were followed concurrently. No therapy altered glycaemic control or body weight. By the study end, both monotherapies improved renal function, decreasing glomerular hyperfiltration and albuminuria. All therapies prevented tubulointerstitial collagen deposition, but glomerular mesangial expansion was unaffected. Renal cortical concentrations of ATP, ADP, AMP, cAMP, creatinine phosphate and ATP:AMP ratio were increased by diabetes and mostly decreased with therapy. A higher creatine phosphate:ATP ratio in diabetic kidney cortices, suggested a decrease in ATP consumption. Diabetes elevated glucose 6-phosphate, fructose 6-phosphate and oxidised (NAD+ and NADP+) and reduced (NADH) nicotinamide dinucleotides, which therapy decreased generally. Diabetes increased mitochondrial oxygen consumption (OCR) at complex II-IV. MitoQ further increased OCR but decreased ATP, suggesting mitochondrial uncoupling as its mechanism of action. MitoQ showed renoprotection equivalent to ramipril but no synergistic benefits of combining these agents were shown.

Variation in Basal Body Localisation and Targeting of Trypanosome RP2 and FOR20 Proteins.

TOF-LisH-PLL motifs define FOP family proteins; some members are involved in flagellum assembly. The critical role of FOP family protein FOR20 is poorly understood. Here, we report relative localisations of the four FOP family proteins in parasitic Trypanosoma brucei: TbRP2, TbOFD1 and TbFOP/FOP1-like are mature basal body proteins whereas TbFOR20 is present on pro- and mature basal bodies - on the latter it localises distal to TbRP2. We discuss how the data, together with published work for another protist Giardia intestinalis, informs on likely FOR20 function. Moreover, our localisation study provides convincing evidence that the antigen recognised by monoclonal antibody YL1/2 at trypanosome mature basal bodies is FOP family protein TbRP2, not tyrosinated α-tubulin as widely stated in the literature. Curiously, FOR20 proteins from T. brucei and closely related African trypanosomes possess short, negatively-charged N-terminal extensions absent from FOR20 in other trypanosomatids and other eukaryotes. The extension is necessary for protein targeting, but insufficient to re-direct TbRP2 to probasal bodies. Yet, FOR20 from the American trypanosome T. cruzi, which lacks any extension, localises to pro- and mature basal bodies when expressed in T. brucei. This identifies unexpected variation in FOR20 architecture that is presently unique to one clade of trypanosomatids.

Molecular detection of Toxoplasma gondii in water samples from Scotland and a comparison between the 529bp real-time PCR and ITS1 nested PCR.

Waterborne transmission of Toxoplasma gondii is a potential public health risk and there are currently no agreed optimised methods for the recovery, processing and detection of T. gondii oocysts in water samples. In this study modified methods of T. gondii oocyst recovery and DNA extraction were applied to 1427 samples collected from 147 public water supplies throughout Scotland. T. gondii DNA was detected, using real time PCR (qPCR) targeting the 529bp repeat element, in 8.79% of interpretable samples (124 out of 1411 samples). The samples which were positive for T. gondii DNA originated from a third of the sampled water sources. The samples which were positive by qPCR and some of the negative samples were reanalysed using ITS1 nested PCR (nPCR) and results compared. The 529bp qPCR was the more sensitive technique and a full analysis of assay performance, by Bayesian analysis using a Markov Chain Monte Carlo method, was completed which demonstrated the efficacy of this method for the detection of T. gondii in water samples.

Prevalence, species identification and genotyping Cryptosporidium from livestock and deer in a catchment in the Cairngorms with a history of a contaminated public water supply.

BACKGROUND: The apicomplexan parasite Cryptosporidium represents a threat to water quality and public health. An important zoonotic species involved in human cryptosporidiosis from contaminated water is Cryptosporidium parvum (C. parvum), the main reservoirs of which are known to be farm livestock particularly neonatal calves, although adult cattle, sheep, lambs and wildlife are also known to contribute to catchment loading of C. parvum. This study aimed to establish Cryptosporidium prevalence, species and genotype in livestock, deer and water in a catchment with a history of Cryptosporidium contamination in the public water supply. METHODS: A novel method of processing adult ruminant faecal sample was used to concentrate oocysts, followed by a nested species specific multiplex (nssm) PCR, targeting the 18S rRNA gene, to speciate Cryptosporidium. A multilocus fragment typing (MLFT) tool was used, in addition to GP60 sequencing, to genotype C. parvum positive samples. RESULTS: A very high prevalence of Cryptosporidium was detected, with speciation identifying a predominance of C. parvum in livestock, deer and water samples. Four GP60 subtypes were detected within C. parvum with the majority IIaA15G2R1 which was detected in all host species and on all farms. Multilocus fragment typing further differentiated these into 6 highly related multilocus genotypes. CONCLUSION: The high prevalence of Cryptosporidium detected was possibly due to a combination of the newly developed sample processing technique used and a reflection of the high rates of the parasite present in this catchment. The predominance of C. parvum in livestock and deer sampled in this study suggested that they represented a significant risk to water quality and public health. Genotyping results suggested that the parasite is being transmitted locally within the study area, possibly via free-roaming sheep and deer. Further studies are needed to verify particular host associations with subtypes/MLGs. Land and livestock management solutions to reduce Cryptosporidium on farm and in the catchment are planned with the aim to improve animal health and production as well as water quality and public health.

In vitro evaluation of the potential for resistance development to ceragenin CSA-13.

OBJECTIVES: Though most bacteria remain susceptible to endogenous antimicrobial peptides, specific resistance mechanisms are known. As mimics of antimicrobial peptides, ceragenins were expected to retain antibacterial activity against Gram-positive and -negative bacteria, even after prolonged exposure. Serial passaging of bacteria to a lead ceragenin, CSA-13, was performed with representative pathogenic bacteria. Ciprofloxacin, vancomycin and colistin were used as comparators. The mechanisms of resistance in Gram-negative bacteria were elucidated. METHODS: Susceptible strains of Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii were serially exposed to CSA-13 and comparators for 30 passages. MIC values were monitored. Alterations in the Gram-negative bacterial membrane composition were characterized via mass spectrometry and the susceptibility of antimicrobial-peptide-resistant mutants to CSA-13 was evaluated. RESULTS: S. aureus became highly resistant to ciprofloxacin after <20 passages. After 30 passages, the MIC values of vancomycin and CSA-13 for S. aureus increased 9- and 3-fold, respectively. The Gram-negative organisms became highly resistant to ciprofloxacin after <20 passages. MIC values of colistin for P. aeruginosa and A. baumannii increased to ≥100 mg/L after 20 passages. MIC values of CSA-13 increased to ∼20-30 mg/L and plateaued over the course of the experiment. Bacteria resistant to CSA-13 displayed lipid A modifications that are found in organisms resistant to antimicrobial peptides. CONCLUSIONS: CSA-13 retained potent antibacterial activity against S. aureus over the course of 30 serial passages. Resistance generated in Gram-negative bacteria correlates with modifications to the outer membranes of these organisms and was not stable outside of the presence of the antimicrobial.