Perception of patient habitus and the influence on exposure factor selection and resultant imparted dose

INTRODUCTION

Exposure factor selection influences ionising radiation dose and image quality in projection radiography. Radiographers have a duty to comply with legislation, ensuring doses (resulting from exposure factor selection) are kept ALARP. Hence, this paper aims to explore variation in patient habitus perceptions among final-year student radiographers and any influence on imparted dose due to exposure factor selection.

METHODS

Institutional ethics was granted. Student radiographers engaged in a 2-stage primary research study. Students were asked to select exposure factors (kVp and mAs values) and the most appropriate BMI category for several models undergoing a routine anteroposterior abdomen projection. Monte-Carlo simulation software was utilised to establish the absorbed and effective dose for these exposures. SPSS software was used to conduct statistical analysis of this data.

RESULTS

A response rate of 19% (n = 14) was recorded. The findings identified variation in habitus perception with greater variation among female models. (p = 0.002). There was significant variation in exposure factor selection and ionising radiation dose, particularly between the male and female models. There was a significant difference between the healthy, overweight, and obese female models for absorbed (p = 0.032) and effective dose (p = 0.032) but not for the male models.

CONCLUSION

There was a distinct difficulty recognising overweight and obese models and inconsistency regarding the selection of exposure factors. It was concluded that male models were more likely to receive a greater dose than females due to higher proposed exposure factors.

IMPLICATIONS FOR PRACTICE

This study adds to the existing evidence base, providing insight into the perceptions of radiography students and the effect on exposure factor selection. This study will likely stand as a baseline for further investigation into competency levels among qualified radiographers to improve radiation protection.

Cervical Spinal Cord Stimulation for Failed Neck Surgery Syndrome

PURPOSE OF REVIEW

Cervical spine pain with or without radicular symptoms is a common condition leading to high utilization of the healthcare system with over 10 million medical visits per year. Many patients undergo surgical interventions and unfortunately are still left with neck and upper extremity pain, sometimes referred to as "Failed Neck Surgery Syndrome." When these options fail, cervical spinal cord stimulation can be a useful tool to decrease pain and suffering as well as reduce prescription medication use.

RECENT FINDINGS

Spinal cord stimulation is a well-established therapy for chronic back and leg pain and is becoming more popular for neck and upper extremity pain. Recent studies have explored cervical spinal cord stimulation with successful outcomes regarding improved pain scores, functional outcomes, and reduction of prescription medication use. Continued research into cervical spinal cord stimulation is essential for maximizing its therapeutic potential for patients with chronic neck and upper extremity pain. This review highlights the importance of cervical spinal cord stimulation as an option for patients with failed neck surgery syndrome.

Current Review of Regenerative Medicine Therapies for Spine-Related Pain

PURPOSE OF REVIEW

Persistent spinal pain syndromes are pervasive and lead to functional impairment, increased healthcare utilization, potential disability, and high societal costs. Spinal (cervical, thoracic, lumbar, and sacroiliac joint) pain includes mechanical, degenerative, inflammatory, oncologic, and infectious etiologies. Regenerative medicine is a novel biotechnology targeting mechanical, degenerative, and inflammatory conditions believed to cause pain. Preparations including platelet-rich plasma, mesenchymal stem cells (adipose tissue and bone marrow aspirate concentrates), and growth factors are derived from an autologous donor. The goal of intervention through guided injection of the regenerative media is to reduce inflammation and reverse the degenerative cascade in hopes of restoring normal cellular composition (physiologic homeostasis) and anatomical function to improve pain and function. The authors review limited research supporting the use of platelet-rich plasma injections for facet joint arthropathy and sacroiliac joint pain compared to traditional steroid treatments, as well as the use of platelet rich plasma or mesenchymal stem cells for lumbar discogenic and radicular pain.

RECENT FINDINGS

Current evidence to support regenerative medicine for spine-related pain is limited. Although several studies demonstrated a reduction in pain, many of these studies had a small number of participants and were case series or prospective trials. Regenerative medicine treatments lack evidence for the treatment of spine-related pain. Large randomized controlled trials are needed with consistent study protocols to make further recommendations.

Hypoxia-Inducible Transgelin-2 Confers Treatment Resistance through Activation of PI3K/Akt/GSK3β Pathway in Glioblastoma

PURPOSE/OBJECTIVE(S)

Glioblastoma (GBM) patients with wild-type IDH experience worse survival response to the standard treatment of surgery followed by radiation therapy (RT) and temozolomide (TMZ) chemotherapy compared to their mutant IDH counterparts. This treatment has remained relatively ineffective partly due to the highly invasive phenotype of GBM leading to therapeutic resistance and tumor recurrence. Hypoxia is one of the key characteristic features of GBM which results in cancer metastasis and confers treatment resistance. Therefore, it is paramount to identify targets to help overcome hypoxia-induced treatment resistance in glioblastoma. Our lab has identified transgelin-2 (TAGLN2) to be significantly upregulated in IDH-wt GBM through multiple molecular profiling studies. This study aims to understand the mechanisms by which TAGLN2 confers treatment resistance for developing additional treatments for GBM. Additionally, active drug development efforts are also underway to target TAGLN2 for circumventing these therapeutic resistance mechanisms for effective GBM therapy.

MATERIALS/METHODS

RNAi-mediated TAGLN2 knockdown (KD) approach was employed to assess the functions of TAGLN2 in GBM patient-derived xenograft (PDX) cell lines. Series of in vitro functional assays were performed to assess the role of TAGLN2 in these cell lines. Cell proliferation, invasion ± RT and/or TMZ were assessed by MTS and Trans-well invasion assays. Subsequently, WB analysis of oncogenic signaling pathways was performed following Transgelin-2 KD. Co-IP assays and Biacore/SPR analyses were performed to study the binding affinity and kinetics for the interaction of PTEN with TAGLN2. Further, cells were intracranially implanted in nude mice to assess the role of TAGLN2 on tumor growth in vivo.

RESULTS

Conditional KD of TAGLN2 reduces cell proliferation, survival and invasive potential of GBM PDX cell lines. TAGLN2 KD also improved the sensitivity of these cells to both TMZ and radiation in vitro, as assessed by proliferation, survival, clonal expansion, and invasion. Histopathological studies of human GBM tumors and mouse xenograft tumors showed elevated expression of TAGLN2 in the peri-necrotic region of the tumors indicating that TAGLN2 protein level was upregulated by hypoxia. We also show that TAGLN2 is induced in hypoxic microenvironments with GBM PDX cell lines and its overexpression may enhance cellular resistance towards conventional therapy. Subsequently, we also show that hypoxia-induced TAGLN2 activates the PI3K/Akt oncogenic pathway through binding and inhibition of PTEN. Finally, in vivo data using an orthotopic xenograft mouse model shows reduction of tumor growth with knockdown of TAGLN2.

CONCLUSION

Our in vitro and in vivo xenograft studies suggest that TAGLN2 confers treatment resistance to GBM contributing to tumor recurrence. Altogether, TAGLN2 may serve as a potential therapeutically vulnerable target in GBM specifically through its role in cell survival and invasion.

Effect of preoperative low-normal cervical length on perinatal outcome after laparotomy-assisted fetoscopic spina bifida repair

OBJECTIVE

To determine if preoperative cervical length in the low-normal range increases the risk of adverse perinatal outcome in patients undergoing fetoscopic spina bifida repair.

METHODS

This was a retrospective cohort study of patients who underwent fetal spina bifida repair between September 2014 and May 2022 at a single center. Cervical length was measured on transvaginal ultrasound during the week before surgery. Eligibility for laparotomy-assisted fetoscopic spina bifida repair was as per the criteria of the Management of Myelomeningocele Study, although maternal body mass index (BMI) up to 40 kg/m² was allowed. Laparotomy-assisted fetoscopic spina bifida repair was performed, with carbon dioxide insufflation via two 12-French ports in the exteriorized uterus. All patients received the same peri- and postoperative tocolysis regimen, including magnesium sulfate, nifedipine and indomethacin. Postoperative follow-up ultrasound scans were performed either weekly (< 32 weeks' gestation) or twice a week (≥ 32 weeks). Perinatal outcome was compared between patients with a preoperative cervical length of 25-30 mm vs those with a cervical length > 30 mm. Logistic regression analyses and generalized linear mixed regression analyses were used to predict delivery at less than 30, 34 and 37 weeks' gestation.

RESULTS

The study included 99 patients with a preoperative cervical length > 30 mm and 12 patients with a cervix 25-30 mm in length. One further case which underwent spina bifida repair was excluded because cervical length was measured > 1 week before surgery. No differences in maternal demographics, gestational age (GA) at surgery, duration of surgery or duration of carbon dioxide uterine insufflation were observed between groups. Cases with low-normal cervical length had an earlier GA at delivery (median (range), 35.2 (25.1-39.7) weeks vs 38.2 (26.0-40.9) weeks; P = 0.01), higher rates of delivery at < 34 weeks (41.7% vs 10.2%; P = 0.01) and < 30 weeks (25.0% vs 1.0%; P < 0.01) and a higher rate of preterm prelabor rupture of membranes (PPROM) (58.3% vs 26.3%; P = 0.04) at an earlier GA (mean ± SD, 29.3 ± 4.0 weeks vs 33.0 ± 2.4 weeks; P = 0.05) compared to those with a normal cervical length. Neonates of cases with low-normal cervical length had a longer stay in the neonatal intensive care unit (20 (7-162) days vs 9 (3-253) days; P = 0.02) and higher rates of respiratory distress syndrome (50.0% vs 14.4%; P < 0.01), sepsis (16.7% vs 1.0%; P = 0.03), necrotizing enterocolitis (16.7% vs 0%; P = 0.01) and retinopathy (33.3% vs 1.0%; P < 0.01). There was an association between preoperative cervical length and risk of delivery at < 30 weeks which was significant only for patients with a maternal BMI < 25 kg/m² (odds ratio, 0.37 (95% CI, 0.07-0.81); P = 0.02).

CONCLUSIONS

Low-normal cervical length (25-30 mm) as measured before in-utero laparotomy-assisted fetoscopic spina bifida repair may increase the risk of adverse perinatal outcomes, including PPROM and preterm birth, leading to higher rates of neonatal complications. These data warrant further research and are of critical relevance for clinical teams considering the eligibility of patients for in-utero spina bifida repair. Based on this evidence, patients with a low-normal cervical length should be aware of their increased risk for adverse perinatal outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Selective TAAR1 agonists induce conditioned taste aversion

RATIONALE

Trace amine-associated receptor 1 (TAAR1) is the best-studied receptor of trace amines, a group of biogenic amines expressed at a relatively low level in the mammalian brain. Growing evidence suggests that TAAR1 plays a critical role in various neuropsychiatric disorders. Given that selective TAAR1 agonists were shown to produce pro-cognition and antipsychotic-like effects as well as to suppress drug use and relapse, they have been proposed to be novel treatments for mental disorders such as schizophrenia and addiction. However, the aversive effects of selective TAAR1 agonists remain largely unknown.

OBJECTIVES

Here, we evaluated whether the selective TAAR1 full agonist RO5166017 and partial agonist RO5263397 could induce conditioned taste aversion (CTA).

RESULTS

We found that RO5166017 and RO5263397 produced significant aversions to both saccharin and NaCl taste novelty. Furthermore, RO5166017 produced CTA to saccharin in TAAR1 heterozygous knockout (taar1^±) and wild-type rats but not in TAAR1 homozygous knockout rats (taar1^-/-), suggesting that TAAR1 was sufficient for the taste aversive stimulus property of RO5166017.

CONCLUSIONS

Taken together, our data indicate that selective TAAR1 agonists could produce strong CTA. Our study urges careful evaluations of the aversive effects of TAAR1 agonists before translating them to clinical use for the treatment of mental disorders.

A model to determine at-home restrictions for cats after treatment of hyperthyroidism with radioiodine

OBJECTIVES

Felinehyperthyroidism is the most common endocrine disease of older cats and radioiodine is considered to be the gold standard treatment. Isolation periods following treatment vary depending on both individual treatment facilities and the relevant legislation of the country; therefore, there is no recognised standardised protocol defining the length of isolation. This work describes how our institution validated that its owner restrictions met dose constraints by using a model of iodine retention to calculate the required duration and nature of owner restrictions.

MATERIALS AND METHODS

The retained radioactivity of cats at the point of discharge was used to simulate the radiation dose to owners in the 90 days following release. The model created was used to calculate the minimum duration of isolation for a range of administered activities and owner restrictions.

RESULTS

Using the model, it was found that when injected with the maximum dose used, 222 MBq radioiodine, it was possible to release cats after 14 days of isolation and keep owner doses below 0.30 mSv (whole-body effective dose constraint for a single radiation source) with some restrictions. It was possible to release after 23 days with no restrictions.

CLINICAL SIGNIFICANCE

The present study provides clinicians with a consistent and verified method in which they can calculate the isolation periods for radioiodine-treated cats.

Activation of trace amine-associated receptor 1 attenuates nicotine withdrawal-related effects

Nicotine addiction is a leading avoidable brain disorder globally. Although nicotine induces a modest reinforcing effect, which is important for the initial drug use, the transition from nicotine use to nicotine addiction involves the mechanisms responsible for the negative consequences of drug abstinence. Recent study suggested that trace amine-associated receptor 1 (TAAR1) is a promising pharmacological target for the modulation of positive reinforcing effects of nicotine. However, whether TAAR1 plays a part in the negative reinforcement of nicotine withdrawal remains to be determined. Here, using a long-access (LA) self-administration model, we investigated whether LA rats show increased nicotine intake and withdrawal symptoms in comparison with saline and ShA rats and then tested the effect of TAAR1 partial agonist RO5263397 on nicotine withdrawal effects. We found that rats from long-access group showed significant abstinence-induced anxiety-like behaviour, mechanic hypersensitivity, increased number of precipitated withdrawal signs and higher motivation for the drug, while rats from short-access did not differ from saline group. TAAR1 partial agonist RO5263397 significantly reduced the physical and motivational withdrawal effects of nicotine in LA rats, as reflected by increased time spent on the open arm in the elevated plus maze (EPM) test, normalized paw withdrawal threshold, decreased withdrawal signs and motivation to self-administer nicotine. This study indicates that activation of TAAR1 attenuates the negative-reinforcing effects of nicotine withdrawal and further suggests TAAR1 as a promising target to treat nicotine addiction.

The selective TAAR1 partial agonist RO5263397 promoted novelty recognition memory in mice

RATIONALE

Trace amine-associated receptor 1 (TAAR1) is a G protein-coupled receptor that has a particular role in regulating dopaminergic, serotonergic, and glutamatergic transmission. TAAR1 agonists have shown pro-cognitive activities. However, it remains largely unknown of the effects of TAAR1 agonists on memory performance.

OBJECTIVES

Here, by using the mice novel object recognition (NOR) test, we examined the effects of the selective TAAR1 partial agonist RO5263397 on recognition memory.

RESULTS

We found that RO5263397 significantly enhanced the retrieval of short-term memory (STM; 20 min after training) both in male and female mice. RO5263397 promoted the retrieval of STM in the wild-type (WT) littermates but not TAAR1-KO mice, indicating that the effects of RO5263397 were dependent on TAAR1. Interestingly, compared to their WT litters, TAAR1-KO mice showed similar levels of STM, suggesting that genetic deletion of taar1 gene did not affect the STM retrieval. Furthermore, RO5263397 also promoted the retrieval of long-term NOR memory (24 h after training).

CONCLUSIONS

These results indicate that TAAR1 activation promotes NOR memory retrieval. Consistent with previous studies, our finding further suggests that TAAR1 agonists have pro-cognitive properties.

Cost effectiveness of romosozumab versus teriparatide for severe postmenopausal osteoporosis in Japan

This study assessed the cost effectiveness of romosozumab versus teriparatide, both sequenced to alendronate, for the treatment of severe postmenopausal osteoporosis in Japan, using bone mineral density (BMD) efficacy data. Results show that romosozumab/alendronate produces greater health benefits at a lower cost than teriparatide/alendronate.

INTRODUCTION

This study aims to assess the cost effectiveness of romosozumab versus teriparatide, both sequenced to alendronate, for the treatment of severe postmenopausal osteoporosis in Japanese women previously treated with bisphosphonates.

METHODS

A Markov model was used to assess the relative cost effectiveness of 1 year of romosozumab versus 2 years of teriparatide, both sequenced to alendronate for a total treatment duration of 5 years. Outcomes for a cohort of women with a mean age of 78 years, a T-score ≤-2.5 and a previous fragility fracture were simulated over a lifetime horizon. The analysis was conducted from the perspective of the Japanese healthcare system and used a discount rate of 2% per annum. To inform relative fracture incidence, the bone mineral density (BMD) advantage of romosozumab over teriparatide was translated into relative risks of fracture, using relationships provided by a meta-regression of osteoporosis therapy trials. Outcomes were assessed in terms of lifetime costs (2020 US dollars) and quality-adjusted life years (QALYs).

RESULTS

Base case results showed that, compared with teriparatide/alendronate, romosozumab/alendronate reduced costs by $5134 per patient and yielded 0.045 additional QALYs. Scenario analyses and probabilistic sensitivity analysis confirmed that results are robust to uncertainty in model assumptions and inputs.

CONCLUSION

Results show that romosozumab/alendronate produces greater health benefits at a lower total cost than teriparatide/alendronate.

Activation of trace amine-associated receptor 1 selectively attenuates the reinforcing effects of morphine

BACKGROUND AND PURPOSE

Trace amine-associated TA₁ receptors play critical roles in regulating dopamine transmission. Previous studies showed that pharmacologically or genetically manipulating the activity of TA₁ receptors modulates addiction-like behaviours associated with psychostimulants. However, little is known about whether TA₁ receptor modulation would regulate the behavioural effects of opioids.

EXPERIMENTAL APPROACH

Effects of the selective TA₁ receptor partial agonist RO5263397 on the addiction-related and antinociceptive effects of morphine were systematically assessed in male rats and mice.

KEY RESULTS

RO5263397 attenuated the expression of morphine-induced behavioural sensitization in wildtype but not TA₁ receptor knockout mice. RO5263397 shifted the dose-effect curve of morphine self-administration downward and reduced the breakpoint in a progressive ratio schedule of reinforcement but did not affect food self-administration in rats. RO5263397 decreased the cue- and drug-induced reinstatement of morphine-seeking behaviour in rats. RO5263397 alone did not trigger reinstatement of morphine-seeking behaviour or change locomotor activity in rats with a history of morphine self-administration. However, RO5263397 did not affect the expression of morphine-induced conditioned place preference in mice or rats. RO5263397 did not affect naltrexone-precipitated jumping behaviour or naltrexone-induced conditioned place aversion in morphine-dependent mice. Furthermore, RO5263397 did not affect the analgesic effects of morphine in an acute nociception model in mice and a chronic pain model in rats.

CONCLUSION AND IMPLICATIONS

These results indicated that TA₁ receptor activation selectively attenuated the reinforcing, but not withdrawal or antinociceptive effects of morphine, suggesting that selective TA₁ receptor agonists might be useful to combat opioid addiction, while sparing the analgesic effects.

TAAR1 agonists attenuate extended-access cocaine self-administration and yohimbine-induced reinstatement of cocaine-seeking

BACKGROUND AND PURPOSE

The trace amine-associated receptor 1 (TAAR1) negatively modulates dopamine transmission. Our previous studies demonstrated that TAAR1 agonists attenuated cue- and drug-induced cocaine-seeking and increased the elasticity of the cocaine demand curve, in the short-access cocaine self-administration model. Compulsive use of cocaine, which is an essential criterion of cocaine use disorder, can be induced by extended access to cocaine self-administration.

EXPERIMENTAL APPROACH

To characterize the role of TAAR1 in compulsive cocaine use, we evaluated the effects of activation of TAAR1 on cocaine intake, cocaine binge and cue-induced cocaine-seeking using the extended-access cocaine self-administration model in adult male Sprague-Dawley rats. We also investigated the role of TAAR1 in stress-triggered cocaine relapse by using the α₂ -adrenoceptor antagonist yohimbine-induced reinstatement of cocaine-seeking.

KEY RESULTS

The selective TAAR1 partial agonist RO5263397 attenuated cocaine intake and did not develop tolerance during the 10-day extended-access cocaine self-administration. RO5263397 reduced a 12-h binge intake of cocaine after forced abstinence. RO5263397 also decreased cue-induced cocaine-seeking after prolonged abstinence from extended-access cocaine self-administration. Furthermore, RO5263397 and the selective TAAR1 full agonist RO5166017 reduced yohimbine-induced reinstatement of cocaine-seeking behaviour.

CONCLUSION AND IMPLICATIONS

Activation of TAAR1 attenuated extended-access cocaine self-administration and stress-induced cocaine reinstatement. These results suggest that TAAR1 agonists are promising pharmacological interventions to treat cocaine use disorder and relapse.

Working with Insulin, Carbohydrates, Ketones and Exercise to Manage Diabetes (WICKED): evaluation of a self-management course for young people with Type 1 diabetes

AIMS

To evaluate a 5-day self-management education course for young people with Type 1 diabetes and assess its effects on knowledge, self-efficacy, beliefs, distress, self-management behaviours and HbA_1c .

METHODS

This is an evaluation of a structured education course. Young people (aged 16-24 years) with Type 1 diabetes were recruited from three diabetes centres. In the first centre, participants completed self-report measures of knowledge, self-efficacy, positive and negative outcome expectancies, and hypoglycaemic worries at baseline (n=47) and the end of the course (n=42). In two additional centres, participants completed these and other measures assessing self-management behaviours, cognitive adaptation to diabetes and diabetes distress at baseline (n=32), the end of the course (n=27) and 3-month follow-up (n = 27). HbA_1c levels were recorded at baseline (n=79), 6 months (n=77) and 12 months (n=65).

RESULTS

There were statistically significant increases in self-report knowledge, self-efficacy, positive outcome expectancies and self-management behaviours, and a statistically significant decrease in negative outcome expectances, between baseline and the end of the course. There were also statistically significant increases in self-report knowledge, self-efficacy, self-management behaviours and cognitive adaptation to diabetes between baseline and 3-month follow-up. Compared with baseline, HbA_1c levels decreased by a mean (sd) of 5.44 (19.93) mmol/mol (0.48%) at 6 months (P=0.019), and by 5.98 (23.32) mmol/mol (0.54%) at 12 months (P =0.043).

DISCUSSION

The results indicate the potential benefits of a self-management course designed to address the developmental needs and challenges faced by young people with Type 1 diabetes. Further studies with larger numbers and appropriate controls are required to confirm these initial findings.