Adaptation of sea turtles to climate warming: Will phenological responses be sufficient to counteract changes in reproductive output?

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a "middle of the road" scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26-43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from -20 to -191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.

Design, synthesis, molecular docking and biological evaluation of thiophen-2-iminothiazolidine derivatives for use against Trypanosoma cruzi.

In this study, we designed and synthesized a series of thiophen-2-iminothiazolidine derivatives from thiophen-2-thioureic with good anti-Trypanosoma cruzi activity. Several of the final compounds displayed remarkable trypanocidal activity. The ability of the new compounds to inhibit the activity of the enzyme cruzain, the major cysteine protease of T. cruzi, was also explored. The compounds 3b, 4b, 8b and 8c were the most active derivatives against amastigote form, with significant IC50 values between 9.7 and 6.03µM. The 8c derivative showed the highest potency against cruzain (IC50=2.4µM). Molecular docking study showed that this compound can interact with subsites S1 and S2 simultaneously, and the negative values for the theoretical energy binding (Eb=-7.39kcal·mol(-1)) indicates interaction (via dipole-dipole) between the hybridized sulfur sp(3) atom at the thiazolidine ring and Gly66. Finally, the results suggest that the thiophen-2-iminothiazolidines synthesized are important lead compounds for the continuing battle against Chagas disease.

Resistance training suppresses intra-abdominal fatty acid synthesis in ovariectomized rats.

Ovarian hormone loss is associated with a shift in fat distribution to intra-abdomin al adipose tissue (intra-AAT) depots and with lipid metabolism disorders, which predisposes individuals to developing insulin resistance. Resistance training (RT) prevents increases in intra-AAT after ovarian hormone loss. However, the molecular mechanisms underlying these changes remain unclear. We investigated the effects of ovariectomy and RT on gene expression related to lipogenesis and fat oxidation in the intra-AAT of ovariectomized rats. Sprague-Dawley rats (n=6/group) were divided into the groups: sham-sedentary, ovariectomized-sedentary, sham-RT and ovariectomized-RT. RT groups performed a 10-week climbing program on a ladder with progressive overload. Intra-AAT was subjected to morphometric and mRNA analysis. Ovariectomized-sedentary group had larger adipocytes and higher expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), sterol regulatory element-binding protein-1c (SREBP-1c), stearoyl-CoA desaturase-1 (SCD-1), acetyl-CoA carboxylase (ACC), hormone-sensitive lipase (HSL) and lower expression of the oxidative carnitinepalmitoyltransferase-I (CPT-1). RT counteracted OVX-induced increases in PPAR-γ and SCD-1 and decreased SREBP-1c. ACC and HSL were downregulated in ovariectomized-RT compared with the ovariectomized-sedentary group. Ovariectomized-RT group had the highest CPT-1 gene expression. Adipocyte size decreased in ovariectomized-RT group. Results suggest that RT reduces intra-AAT adipocyte size in ovariectomized rats by suppressing intra-AAT fatty acid synthesis and enhancing fatty acid ß-oxidation.

Chronic ethanol alters adrenergic receptor gene expression and produces cognitive deficits in male mice.

Hyperkateifia and stress-induced alcohol cravings drive relapse in individuals with alcohol use disorder (AUD). The brain stress signal norepinephrine (also known as noradrenaline) tightly controls cognitive and affective behavior and was thought to be broadly dysregulated with AUD. The locus coeruleus (LC) is a major source of forebrain norepinephrine, and it was recently discovered that the LC sends distinct projections to addiction-associated regions suggesting that alcohol-induced noradrenergic changes may be more brain region-specific than originally thought. Here we investigated whether ethanol dependence alters adrenergic receptor gene expression in the medial prefrontal cortex (mPFC) and central amgydala (CeA), as these regions mediate the cognitive impairment and negative affective state of ethanol withdrawal. We exposed male C57BL/6J mice to the chronic intermittent ethanol vapor-2 bottle choice paradigm (CIE-2BC) to induce ethanol dependence, and assessed reference memory, anxiety-like behavior and adrenergic receptor transcript levels during 3-6 days of withdrawal. Dependence bidirectionally altered mouse brain α1 and ß receptor mRNA levels, potentially leading to reduced mPFC adrenergic signaling and enhanced noradrenergic influence over the CeA. These brain region-specific gene expression changes were accompanied by long-term retention deficits and a shift in search strategy in a modified Barnes maze task, as well as greater spontaneous digging behavior and hyponeophagia. Current clinical studies are evaluating adrenergic compounds as a treatment for AUD-associated hyperkatefia, and our findings can contribute to the refinement of these therapies by increasing understanding of the specific neural systems and symptoms that may be targeted.

(2E,4E)-1-(2-Hy-droxy-phen-yl)-5-phenyl-penta-2,4-dien-1-one.

In the structure of the title chalcone, C(17)H(14)O(2), derived from cinnamaldehyde, the olefine group has a trans configuration. The mol-ecular conformation is stabilized by an intra-molecular O-H⋯O hydrogen-bond inter-action with graph-set motif S(6).

Anaesthesia of hatchling green sea turtles (Chelonia mydas) with intramuscular ketamine-medetomidine-tramadol.

OBJECTIVE: To characterise intramuscular ketamine-medetomidine-tramadol anaesthesia in hatchling green sea turtles (Chelonia mydas). STUDY DESIGN: Prospective clinical trial. ANIMALS: Ten hatchling green sea turtles. MATERIALS AND METHODS: Prior to anaesthesia, cardiopulmonary parameters, cloacal temperature, and venous blood gas and biochemistry were obtained from hatchling green sea turtles while they were being gently restrained. Animals were then anaesthetised with ketamine (5 mg kg-1 ), medetomidine (0.05 mg kg-1 ) and tramadol (5 mg kg-1 ) via intramuscular injection. Turtles were checked for the depth of anaesthesia at five-min intervals by recording reflexes (righting, palpebral, pinch, cloacal) and measuring heart rate, respiratory rate and cloacal temperature. After 20 min, a second venous blood sample was obtained for further blood gas and biochemical analysis and the medetomidine was antagonised using atipamezole (5:1 medetomidine, 0.25 mg kg-1 ). RESULTS: All turtles were successfully anaesthetised with a mean time to induction of 3.4 min (±1). In all animals, a loss of reflexes (except for palpebral reflex) and voluntary movement was observed for the entire 20 min. Anaesthesia resulted in marked apnoea for the duration of the procedure. Venous blood gas and biochemistry analysis indicated that a 20 min period of apnoea had no measurable effects on venous blood gas results. All turtles recovered uneventfully after atipamazole antagonisation, with a mean time to first breath 4.5 min (±3.7), and mean recovery time 15.5 min (±15.4). CONCLUSIONS AND CLINICAL RELEVANCE: Intramuscular ketamine-medetomidine-tramadol, antagonised with atipamazole appears to be an effective anaesthetic protocol in hatchling green sea turtles for short procedures with no deleterious effects on venous blood gases or biochemistry.

BAY 12-9566, a novel inhibitor of matrix metalloproteinases with antiangiogenic activity.

Matrix metalloproteinases (MMPs) have been implicated in tumor cell invasion, metastasis, and angiogenesis. BAY 12-9566, a novel, non-peptidic biphenyl MMP inhibitor, has shown preclinical activity on a broad range of tumor models and is currently in clinical development. The purpose of this study was to investigate the antiangiogenic activity of BAY 12-9566. In vitro, BAY 12-9566 prevented matrix invasion by endothelial cells in a concentration-dependent manner (IC50 = 8.4x10(-7) M), without affecting cell proliferation. In vivo, oral daily administration of BAY 12-9566 (50-200 mg/kg) inhibited angiogenesis induced by basic fibroblast growth factor in the Matrigel plug assay, reducing the hemoglobin content of the pellets. Histological analysis showed a reduction in the amount of functional vessels within the Matrigel. We conclude that the MMP inhibitor BAY 12-9566 inhibits angiogenesis, a property that further supports its clinical development as an antimetastatic agent.

Aspen shaving versus chip bedding: effects on breeding and behavior.

The choice of laboratory cage bedding material is often based on both practical and husbandry issues, whereas behavioral outcomes rarely appear to be considered. It has been noted that a breeding success difference appears to be associated with the differential use of aspen chip and aspen shaving bedding in our facility; therefore, we sought to analyze breeding records maintained over a 20-month period. In fact, in all four mouse strains analyzed, shaving bedding was associated with a significant increase in average weanlings per litter relative to chip bedding. To determine whether these bedding types also resulted in differences in behaviors associated with wellbeing, we examined nest building, anxiety-like, depressive-like (or helpless-like), and social behavior in mice housed on chip versus shaving bedding. We found differences in the nests built, but no overall effect of bedding type on the other behaviors examined. Therefore, we argue that breeding success, perhaps especially in more challenging strains, is improved on shaving bedding and this is likely due to improved nest-building potential. For standard laboratory practices, however, these bedding types appear equivalent.

Calcitonin and CGRP block bombesin- and substance P-induced increases in airway tone.

Calcitonin gene-related peptide (CGRP) and calcitonin (C) are two peptides that are cocontained and probably coreleased with the potent bronchocontrictors, bombesin (B) and substance P (SP), within the lung. Although CGRP and C have a wide intrapulmonary distribution, their actions have not been well defined. By the use of a computerized lung mechanics analyzer, changes in response to 10-min infusions of these agents were measured in spontaneously breathing, anesthetized guinea pigs. Infusion of 0.3 nmol.kg-1.min-1 CGRP and 2 nmol.kg-1.min-1 C caused little change in lung mechanics. Infusion of 0.06 nmol.kg-1.min-1 B and 0.3 nmol.kg-1.min-1 SP caused a marked increase in inspiratory, expiratory, and total pulmonary resistance (RT), from base-line values (P less than 0.02), with a maximal effect at 10 min postinfusion (PI) [RT = 326 +/- 20% (SE) (B), 490 +/- 73% (SP)]. Coinfusion of C or CGRP with B or SP at the above concentrations caused a marked reduction in SP - [RT = 189 +/- 28% (C), 142 +/- 16% (CGRP) at 10 min PI] and B - [RT = 157 +/- 18% (C), 158 +/- 10% (CGRP) at 10 min PI] induced changes in resistance (P less than 0.015). The mode of action of C and CGRP is unknown, but these peptides may antagonize the effects of B and SP via autonomic pathways by interfering with B- or SP-induced changes in intracellular calcium concentrations or by increasing intracellular cAMP levels by binding to specific cellular receptors linked to adenylate cyclase.

Effect of spontaneous and mechanical breathing on dynamic lung mechanics in hyaline membrane disease.

We measured then compared the dynamic lung mechanics of spontaneous breaths and mechanical breaths in 9 mechanically ventilated neonates with hyaline membrane disease. All were receiving intermittent mandatory ventilation. All breathed spontaneously between ventilator breaths. Tidal volume, transpulmonary pressure, dynamic lung compliance, airways resistance, and peak inspiratory and peak expiratory gas flows were determined for both the mechanical and the spontaneous breaths. The mechanical breaths consistently had larger tidal volumes, higher transpulmonary pressures, higher airway resistance, and lower lung compliance values (P less than 0.05). Peak inspiratory and expiratory gas flows were also higher (P less than 0.01) during mechanical breathing. The spontaneous breaths generated by patients and the mechanical breaths generated by mechanical ventilators are different. The lung mechanics measurements of these two different types of breathing should be collected, analyzed, and reported separately.

Real-time in vivo loading in the lumbar spine: part 1. Interbody implant: load cell design and preliminary results.

STUDY DESIGN: Instrumented interbody implants were placed into the disc space of a motion segment in two baboons. During the animal's activities, implants directly measured in vivo loads in the lumbar spine by telemetry transmitter. OBJECTIVES: Develop and test an interbody implant-load cell and use the implant to measure directly loads imposed on the lumbar spine of the baboon, a semiupright animal. SUMMARY OF BACKGROUND DATA: In vivo forces in the lumbar spine have been estimated using body weight calculations, moment arm models, dynamic chain models, electromyogram measurements, and intervertebral disc pressure measurements. METHODS: An analytical model was used to determine the force-strain relation in a customized interbody implant. After validation by finite element modeling, strain gauges were mounted onto the implant and connected to a telemetry transmitter. Implants were placed surgically into the L4-L5 disc space of skeletally mature baboons and the transmitter in the flank. After surgery, load data were collected from the animals during activities. Radiographs were taken monthly to assess fusion. RESULTS: The implant-load cell is sufficiently sensitive to monitor dynamic changes in strain and load. During extreme activity, highest measurable strain values were indicative of loads in excess of 2.8 times body weight. CONCLUSIONS: The study technique and technology are efficacious for measuring real-time in vivo loads in the spine. Measuring load on an intradiscal implant over the course of healing provides key information about the mechanics of this process. Loads may be used to indicate performance demands on the intervertebral disc and interbody implants for subsequent implant design.

In vitro simulation. Early results of stereotaxy for pedicle screw placement.

STUDY DESIGN: Frameless stereotaxy with doppler ultrasound and three dimensional computer model registration is assessed in vitro for pedicle screw placement. OBJECTIVE: To identify feasibility of pedicle screw navigation and placement using this technology. SUMMARY OF BACKGROUND DATA: Inaccurate pedicle screw placement can lead to neurovascular injury or suboptimal fixation. Present techniques in pedicle screw placement involve only confirmation of hole orientation. METHOD: Forty-four pedicle screws were placed in lumbosacral models and cadaver specimens. Accuracy was assessed with a computed tomography scan and vertebral cross sectioning. RESULTS: All screws were intrapedicular. Accuracy of anterior cortical fixation was 1.5 mm, with a range of 2.5 mm. CONCLUSION: In vitro frameless stereotaxy is accurate for pedicle screw placement. This technology adds a component of navigation to pedicle screw placement.

4,6,4'-Trimethylangelicin induces interstrand cross-links in mammalian cell DNA.

4,6,4'-Trimethylangelicin, a well-known effective photosensitizer described as a pure monofunctional reactant with DNA, can induce interstrand cross-links in mammalian cell DNA in vivo (about 15% relative to 8-methoxypsoralen), as observed using alkaline elution and Chinese hamster ovary cells. Experiments performed using the two-step irradiation method and HeLa cells support these data. In contrast with 4,6,4'-trimethylangelicin, 4'-methylangelicin and 4,4'-dimethylangelicin do not form interstrand cross-links. These results are consistent with those recently reported by Chen et al. (X. Chen, J. Kagan, F. Dall'Acqua, D. Averbeck and E. Bisagni, J. Photochem. Photobiol. B: Biol, 22 (1994) 51-57) using pBR322 and M13 DNA. The cross-linking ability of 4,6,4'-trimethylangelicin does not seem to be related to a particular feature of these DNAs but to the compound itself.

Further evaluation of amniotic membrane banking for transplantation in ocular surface diseases.

Objective: To define the best conditions for amniotic membrane preparation, storage and banking in its use for corneal reconstruction. Methods: Amniotic membrane pieces were prepared under sterile conditions from placentas selected on the basis of donor medical and social history, serology, microbiological tests and histology. The pieces were kept at -140 degrees C but before grafting they were thawed and stored at 4 degrees C in RPMI medium, to have a preparation usable within 72 h. This procedure was validated by testing its therapeutic effectiveness in 25 patients 13 of which had corneal ulcers of various origin, 3 had sequelae of herpes simplex keratitis, 3 band keratopathy and 6 corneal stem cell deficiency due to chemical or thermal burns. Results: The preparation showed appreciable anti-inflammatory and analgesic effects. In the absence of corneal stem cell deficiency a stable re-epithelialisation was achieved in 15 out of 19 patients. When the limbus was lesioned, the amniotic membrane decreased vascularization and increased the number of corneal epithelial cells only in 1 of the 6 patients. No adverse reactions attributable to the tissue were recorded. Conclusions: A ready-to-use amniotic membrane preparation stored at 4 degrees C after cryopreservation has been tested in corneal reconstruction. Like the amniotic membrane thawed immediately before grafting, this preparation displayed full therapeutic effect in epithelial defects with stromal ulceration but without severe limbal stem cell deficiency. In two years banking activity 463 pieces of the preparation were successfully distributed to 90 Italian hospitals.