Developmental asynchrony might not reduce fitness in early life in painted turtles.

Synchronous hatching and emergence of turtles from nests may be adaptive in predator avoidance during dispersal. However, little is known about the phenotypic consequences of such synchrony or the generality of predator avoidance in driving the evolution of this trait. Colbert et al. (2010) found that less advanced embryos hatched early in the presence of more advanced sibs, sustaining a persistent reduction in neuromuscular function. In this study, we experimentally assessed the influence of such accelerated embryonic development on hatching success, winter survival, and survival during terrestrial dispersal from the nest. Although we predicted that shortened incubation periods would reduce survival, early-hatching individuals suffered no detectable fitness costs at any stage considered in this study. Incubation temperature did not affect hatching success, and offspring sex did not affect survival across treatment groups. Incubation regime influenced offspring body size and was negatively correlated with dispersal time, however, there was no effect on survival during winter or terrestrial dispersal. Lack of a detectable fitness cost in these key early-life stages associated with hatching synchrony is consistent with a single, predator avoidance origin for this trait and retention in C. picta and other derived turtles via phylogenetic inertia.

Endoscope-assisted techniques for evacuation of acute subdural haematoma in the elderly: The lesser of two evils? A scoping review of the literature.

INTRODUCTION: Surgical evacuation of acute subdural haematoma (ASDH) in the elderly remains a point of contention due to the significant associated mortality. Therefore, there is a dire need for alternative treatment options. Endoscope-assisted techniques (EAT) have been increasingly reported over the last decade with variable outcomes. In this scoping review, we identify studies reporting the use of EAT for ASDH evacuation in elderly patients. Outcomes and patient selection criteria are discussed to identify patients that may benefit from EAT. METHODS: A multi-database literature search was performed between January 1990 and January 2021. Studies including patients aged 60 years or above who underwent EAT for ASDH evacuation with reported outcomes were included. RESULTS: A total of 13 studies and 122 patients were eligible for inclusion. Patient age ranged from 65 to 101 years, and average age from 78.6 to 87.4 years. High comorbidity burden, advanced age, absence of adverse imaging features, and pre-operative neurological status were the most common eligibility criteria for EAT. 52% of all procedures were performed under local anaesthetic (LA). Mortality rates ranged between 0% and 40%, whilst favourable outcomes ranged between 26.7% and 96.4%. Re-bleed was the most commonly reported complication, ranging between 0% and 13%. CONCLUSIONS: EAT pose a viable compromise for elderly patients with ASDH that may be unfit for GA. Heterogeneity of patient selection criteria prevents meaningful comparison between EAT and other approaches, and there is a clear impact of patient selection on outcome among studies reporting EAT. Further studies are required to identify the patient cohort that may benefit from this approach.

A retrospective analysis of emergency referrals and admissions to a regional neurosurgical centre 2016-2018.

BACKGROUND AND OBJECTIVES: Emergencies account for 60% of UK neurosurgical workload. We analysed the emergency referrals made to the on-call neurosurgical registrar in a regional centre over three years, aiming to identify temporal trends in volume of referrals, admission practices and major diagnostic categories contributing to referrals and admissions. METHODS: Individual referrals recorded in on-call databases were processed to extract basic demographics, call timing, diagnosis category and whether the patient was admitted under neurosurgery. Linear regression analysis was used to identify temporal trends across the three years. RESULTS: A total of 18128 calls were made to the on-call registrar between 2016 and 2018, with a significant increase in monthly calls. On average, one call was received every 88 minutes. An increasing proportion of these calls were taken out of office hours. Diagnostic categories accounting for the largest percentage of calls were traumatic brain injury (17.7%) and cauda equina syndrome (13%). Significant increases in referral volume were seen in cauda equina syndrome, traumatic brain injury, spinal trauma and spinal tumours, while no category had a significant decrease. The admission rate was 17.1% - no change was seen in this across the study period, resulting in increasing numbers of admissions, reflecting increasing referrals. Categories most likely to result in admission were hydrocephalus (41.1%), spontaneous subarachnoid haemorrhage (39.4%), intracranial infection (32.6%) and chronic subdural haematoma (CSDH, 32.2%). A change in admission rate was seen only for CSDH, with a significant increase in the percentage of referrals across the study period. CONCLUSION: Emergency neurosurgical referrals continue to rise in the UK at a rate exceeding population growth. This implies a decreasing referral threshold. However, the constant admission rate suggests either an increasing amount of neurosurgical pathology, the threshold for admission/intervention has decreased, or a combination. Neurosurgical services need to adapt in order to meet increasing demands.

Conservation implications of turtle declines in Australia's Murray River system.

Conservation requires rapid action to be effective, which is often difficult because of funding limitations, political constraints, and limited data. Turtles are among the world's most endangered vertebrate taxa, with almost half of 356 species threatened with extinction. In Australia's Murray River, nest predation by invasive foxes (Vulpes vulpes) was predicted to drive turtle declines in the 1980s. We assessed populations of the broad-shelled turtle (Chelodina expansa), eastern long-necked turtle (C. longicollis), and Murray River turtle (Emydura macquarii) in the Murray River and some of its associated waterways. Our results suggest that the predicted decline is occurring. All three species are rare in the lower Murray River region, and were undetected in many locations in South Australia. Moreover, E. macquarii had considerable population aging almost everywhere, possibly due to comprehensive nest destruction by foxes. Chelodina longicollis also had population aging at some sites. Sustained low recruitment has potential to lead to collapses as turtles age, which is particularly worrying because it was predicted over 30 years ago and may have already occurred in South Australia. Our results show that turtle declines were not mitigated since that prediction. If the crash continues, a vertebrate guild responsible for considerable nutrient cycling in the aquatic ecosystem will disappear. Our results highlight a worst-case outcome when species declines are predicted, but insufficiently mitigated.

Critically evaluating best management practices for preventing freshwater turtle extinctions.

Ex situ conservation tools, such as captive breeding for reintroduction, are considered a last resort to recover threatened or endangered species, but they may also help reduce anthropogenic threats where it is difficult or impossible to address them directly. Headstarting, or captive rearing of eggs or neonate animals for subsequent release into the wild, is controversial because it treats only a symptom of a larger conservation problem; however, it may provide a mechanism to address multiple threats, particularly near population centers. We conducted a population viability analysis of Australia's most widespread freshwater turtle, Chelodina longicollis, to determine the effect of adult roadkill (death by collision with motor vehicles), which is increasing, and reduced recruitment through nest predation from introduced European red foxes (Vulpes vulpes). We also modeled management scenarios to test the effectiveness of headstarting, fox management, and measures to reduce mortality on roads. Only scenarios with headstarting from source populations eliminated all risks of extinction and allowed population growth. Small increases in adult mortality (2%) had the greatest effect on population growth and extinction risk. Where threats simultaneously affected other life-history stages (e.g., recruitment), eliminating harvest pressures on adult females alone did not eliminate the risk of population extinction. In our models, one source population could supply enough hatchlings annually to supplement 25 other similar-sized populations such that extinction was avoided. Based on our results, we believe headstarting should be a primary tool for managing freshwater turtles for which threats affect multiple life-history stages. We advocate the creation of source populations for managing freshwater turtles that are greatly threatened at multiple life-history stages, such as depredation of eggs by invasive species and adult mortality via roadkill.

Transversus abdominis plane block in robotic gynecologic oncology: a randomized, placebo-controlled trial.

OBJECTIVE: Although robotic surgery decreases pain compared to laparotomy, postoperative pain can be a concern near the site of a larger assistant trocar site. The aim of this study was to determine the efficacy of transversus abdominis plane (TAP) block on 24-hour postoperative opiate use after robotic surgery for gynecologic cancer. METHODS: Sixty-four subjects with gynecologic malignancies who were scheduled to undergo robotic surgery were enrolled into the study. They were randomized to receive a unilateral TAP block to the side of the assistant port via ultrasound guidance. The block was comprised of 30 cc of 0.25% bupivacaine with 3 mcg/mL epinephrine or saline. Opiate use was measured and converted into IV morphine equivalents. Patient-reported pain was measured using the Brief Pain Inventory (BPI) and Visual Analog Scale (VAS). RESULTS: The treatment group used a mean of 64.9 mg morphine in the first 24h compared to 69.3mg for controls (primary outcome, p=0.52). After age-adjustment, the treatment group used a mean of 11.1mg morphine less than controls (p=0.09). Postoperative pain scores assessed by the BPI (6.44 vs. 6.97, p=0.37) and the VAS (3.12 vs. 3.61, p=0.30) were equivalent. Block placement was uncomplicated in 98.4% of participants with mean BMI of 35.3 kg/m(2). Linear regression revealed an approximate 8.1mg decrease in morphine equivalents used per additional decade of life (p=0.0008). There was a positive correlation between the amount of opiates and BMI with an additional 8.8 mg of morphine per 10 kg/m(2) increase in BMI (p=0.0012). CONCLUSIONS: TAP block is safe and feasible in this patient population with a large proportion of morbid obesity. Preoperative TAP block does not significantly decrease opiate use. However; based on these data, a clinically useful nomogram has been created to aid clinicians in postoperative opiate-dosing for patients based on age and BMI.

Interdisciplinary management of severe intrusion injuries in permanent incisors: a case series.

Intrusion injuries to the permanent dentition are amoung the most severe types of dental injuries, occurring in 0.3-1.9% of all dental trauma cases. The current clinical guidelines in the management of intrusion injuries are based on level B evidence due to the infrequent nature of this type of injury, coupled with a lack of high quality evidence-based studies. This paper presents four cases of severe intrusion injuries that were successfully managed using an interdisciplinary approach. The cases described here highlight the benefits of orthodontic repositioning of severely intruded teeth in the short and medium terms. Although orthodontic repositioning was unsuccessful in the final case, this did not preclude subsequent surgical repositioning. Interdisciplinary collaboration allowed two of the cases described to be effectively managed with premolar autotransplantation alongside orthodontic treatment. The cases demonstrated here indicate the difficulties in providing the current recommended treatment modalities at non-specialist clinics. They accentuate the importance of an immediate referral of such complex cases to a specialist centre where interdisciplinary management is readily available.

A novel hypothesis for the adaptive maintenance of environmental sex determination in a turtle.

Temperature-dependent sex determination (TSD) is widespread in reptiles, yet its adaptive significance and mechanisms for its maintenance remain obscure and controversial. Comparative analyses identify an ancient origin of TSD in turtles, crocodiles and tuatara, suggesting that this trait should be advantageous in order to persist. Based on this assumption, researchers primarily, and with minimal success, have employed a model to examine sex-specific variation in hatchling phenotypes and fitness generated by different incubation conditions. The unwavering focus on different incubation conditions may be misplaced at least in the many turtle species in which hatchlings overwinter in the natal nest. If overwintering temperatures differentially affect fitness of male and female hatchlings, TSD might be maintained adaptively by enabling embryos to develop as the sex best suited to those overwintering conditions. We test this novel hypothesis using the painted turtle (Chrysemys picta), a species with TSD in which eggs hatch in late summer and hatchlings remain within nests until the following spring. We used a split-clutch design to expose field-incubated hatchlings to warm and cool overwintering (autumn-winter-spring) regimes in the laboratory and measured metabolic rates, energy use, body size and mortality of male and female hatchlings. While overall mortality rates were low, males exposed to warmer overwintering regimes had significantly higher metabolic rates and used more residual yolk than females, whereas the reverse occurred in the cool temperature regime. Hatchlings from mixed-sex nests exhibited similar sex-specific trends and, crucially, they were less energy efficient and grew less than same-sex hatchlings that originated from single-sex clutches. Such sex- and incubation-specific physiological adaptation to winter temperatures may enhance fitness and even extend the northern range of many species that overwinter terrestrially.

The design and development of surgical templates for premolar transplants in adolescents.

The aim of designing and fabricating the surgical templates was to assist the surgical component of premolar transplantation, by establishing and replicating the root dimensions of the donor premolar tooth. The correct template could be used to assess the socket preparation (width and depth) prior to placement of the transplant in the recipient site, obviating the need to repeatedly try the donor tooth for fit at the recipient site, thereby minimising trauma to the periodontal ligament of the donor tooth. Seventy-five mandibular premolars and 50 maxillary second premolars were selected with varying stages of root development. All teeth had been extracted for orthodontic reasons. The root was measured for its length (maxL) and maximum (maxW) and minimum width (minW) with digital callipers from standardised reference points. These measurements were then used in the design of premolar transplant templates. The mean measurements for second maxillary premolars were maxL 14.6 mm (± 1.7), maxW 8.3 mm (± 0.5) and minW 4.9 (± 0.3). The mean measurements for mandibular premolars were maxL 14.8 (± 1.6), maxW 7.4 (± 0.6) and minW 5.3 (± 0.5). From these measurements, a range of maxillary second premolar and mandibular premolar templates have been fabricated. These figures also inform the multidisciplinary planning process for the space requirements at the donor site prior to transplantation.

Indications for the use of auto-transplantation of teeth in the child and adolescent.

BACKGROUND: Tooth auto-transplantation has been successfully performed for over 50 years and yet the procedure has still to receive the widespread acceptance that it deserves. AIM: This study demonstrates the numerous clinical situations in which auto-transplantation can be used in order to give a child or adolescent an excellent biological long-term replacement. INDICATIONS: Seven cases are presented that demonstrated the versatility of auto-transplantation in a range of clinical situations. The aim was to show that this technique is not only useful for replacing teeth that are lost due to trauma but has applications for the replacement of teeth that are developmentally missing, or teeth with otherwise poor long-term prognosis. TREATMENT: All cases presented were managed with autotransplatation and included patients with hypodontia, trauma, dilacerated incisors, ankylosis, failed endodontic treatment and aesthetic management of a patient with cleft lip and palate. FOLLOW-UP: Medium and long-term outcomes were demonstrated. CONCLUSIONS: Auto-transplantation provides an excellent outcome in a growing child with the advantage that it is a biologically compatible method of tooth replacement, which promotes pulp and periodontal healing and enables orthodontic movement if necessary.

Are general dental practitioners effective in the management of non-apnoeic snoring using mandibular advancement appliances?

OBJECTIVE: This study assessed the effectiveness of general dental practitioners (GDPs) in the management of subjects with non-apnoeic snoring using a mandibular advancement appliance (MAA), following a one day training course. SUBJECTS AND METHODS: Sixty subjects suffering from simple, non-apnoeic snoring were treated by 15 GDPs, in three hospital centres, using a monobloc mandibular advancement appliance design. All GDPs attended a one day training course prior to the study which covered theoretical and practical training in the use of mandibular advancement appliances. Snoring and level of disturbance were assessed using a questionnaire completed by their sleeping partner before and after a three month treatment period. Daytime sleepiness was assessed by the patients using the Epworth sleepiness scale questionnaire (ESS) before and after a three month treatment period. In addition, patients completed an outcome questionnaire, to assess side-effects experienced from the MAA. RESULTS: A success rate of 48% (95% CI 0.35, 0.61) was achieved in partner-assessed snoring and disturbance levels, following a three month period of MAA treatment. The median ESS score reduced from 9 to 7.5 (95% CI 0, 3). General dental practitioners experienced problems during protrusive bite registrations, with 10% being judged inadequate. CONCLUSION: GDPs were not effective in the management of non-apnoeic snoring using a monobloc appliance after a one day training course. Further training and/or selection of a different design of appliance should be considered for GDPs to become highly competent in this area.

Elective orthognathic treatment decision making: a survey of patient reasons and experiences.

OBJECTIVE: Few studies have explored decisions about orthognathic treatment (OGT) from the patient's perspective. This study describes the factors associated with the patient's decision to have or not have orthognathic treatment, and assesses whether the process can be considered to be informed decision making. DESIGN: A cross-sectional survey employing both interview and questionnaire methods, conducted in four OGT services in Yorkshire. SAMPLE: Participants were patients aged over 16 years, either making an OGT decision over a 6-month period or had made their treatment choice 18-42 months prior to the study start date in 2003. MEASURES: Questionnaires assessed patient demographics, dental history and psychopathology (anxiety, satisfaction with self, body satisfaction, facial appearance); interviews explored patients' reasons for, and experiences of, orthognathic treatment. RESULTS: Of 138 patients approached, 61 participated (mean age 25 years, 66% female). Psychopathology scores were within the normal range. The thematic content analysis of interview transcripts found: reasons given for having OGT were to improve the 'bite', as well as gaining a more normal facial appearance; most patients reported the service information was satisfactory, but about half made negative comments, with some reporting staff communications made them feel worse; knowledge of OGT risks and benefits was poor; patients had strong emotions about their facial appearance and the orthognathic treatment they received, which did not seem to be addressed by current practice. CONCLUSIONS: Some OGT patients do not appear to be making informed decisions about their treatment. They seem to have unmet needs in relation to support for their decision making, and managing the emotional effects of undergoing and adjusting to treatment. The implications for information provision, assessment and support during treatment are discussed.

Clustering of related individuals in a population of the Australian lizard, Egernia frerei.

Stable social aggregations are rarely recorded in lizards, but have now been reported from several species in the Australian scincid genus Egernia. Most of those examples come from species using rock crevice refuges that are relatively easy to observe. But for many other Egernia species that occupy different habitats and are more secretive, it is hard to gather the observational data needed to deduce their social structure. Therefore, we used genotypes at six polymorphic microsatellite DNA loci of 229 individuals of Egernia frerei, trapped in 22 sampling sites over 3500 ha of eucalypt forest on Fraser Island, Australia. Each sampling site contained 15 trap locations in a 100 x 50 m grid. We estimated relatedness among pairs of individuals and found that relatedness was higher within than between sites. Relatedness of females within sites was higher than relatedness of males, and was higher than relatedness between males and females. Within sites we found that juvenile lizards were highly related to other juveniles and to adults trapped at the same location, or at adjacent locations, but relatedness decreased with increasing trap separation. We interpreted the results as suggesting high natal philopatry among juvenile lizards and adult females. This result is consistent with stable family group structure previously reported in rock dwelling Egernia species, and suggests that social behaviour in this genus is not habitat driven.

Protection of the lip from the activator arm of maxillary distractors.

The long spring-loaded distractor arms of maxillary distraction devices can cause pain and ulceration of the upper lip. We describe a simple method to relieve the tension and discomfort on the soft tissues using Silastic tubing.

Unusual indelible enamel staining following fixed appliance treatment.

Two cases are described of indelible enamel staining following fixed appliance therapy. The acquired pigmentation occurred in patients with an identifiable enamel defect prior to treatment. The interaction of factors to cause the staining is discussed and it's prevention in future cases highlighted. Subsequent restoration of the affected teeth is shown.

Desensitization of delta-opioid-induced mobilization of Ca2+ stores in NG108-15 cells.

Activation of delta-opioid receptors in NG108-15 cells induces the release of calcium from an inositol 1,4,5-trisphosphate- sensitive intracellular store. We used fura-2-based digital imaging to study the effects of prolonged exposure to agonist on opioid-induced increases in [Ca2+]i. Exposure to D-Ala2-E-Leu5 enkephalin (DADLE) (1 microM) for 30 min completely desensitized NG108-15 cells to a second DADLE-induced response. The cells recovered gradually over 25 min following washout of DADLE. The desensitization was not due to depletion of intracellular calcium stores and bradykinin failed to cross-desensitize the DADLE-evoked response, although both agonists mobilized the same Ca2+ store. Desensitization induced by 100 nM DADLE was overcome by a higher concentration of DADLE (100 microM). Treatment with 8-cpt-cAMP (0.1 mM) for 30 min did not influence the DADLE-induced increases in [CA2+]i. Phorbol dibutyrate (PdBu) (1 microM) blocked the response completely. Treatment with the inhibitor of cyclic nucleotide-dependent kinases H8 (1 microM) for 45 min did not prevent DADLE-induced desensitization. Treatment with the protein kinase C (PKC) inhibitors staurosporin (10 nM) and GF-109203X (200 nM) for 45 min reduced desensitization. However, down-regulation of PKC by 24 h exposure to PdBu (1 microM) failed to prevent the DADLE-induced desensitization in NG108-15 cells. Thus, we conclude that multiple pathways participated in desensitization of delta-receptor-mediated Ca2+ mobilization, one of which includes PKC.

Effect of nucleosome structure on DNA interstrand cross-linking reactions.

Antitumor agents of the nitrogen mustard family and mitomycin C form interstrand cross-links in duplex DNA. To provide information about the cellular mechanism by which these compounds exert their cytotoxic effects, we examined cross-linking of a nucleosomal core particle formed on a fragment of the 5S RNA gene of Xenopus borealis. For the mustards mechlorethamine, chlorambucil, and melphalan, both sites of monoalkylation and interstrand cross-linking were similar in nucleosomal and free DNA. Some small (two- to three- fold) differences in intensity of cross-linking at some sites were apparent. However, these differences did not appear to correlate with rotational or translational positioning. For mitomycin C, cross-linking was inhibited five- to ten-fold at the nucleosomal dyad and showed attenuation of inhibition toward the ends. Furthermore, rotational positioning also appeared to be a factor, with sites facing inward in the nucleosome less accessible for mitomycin cross-linking. None of these agents demonstrated the 10-base pair periodicity exhibited by hydroxyl radical cleavage of nucleosomal DNA.