Rapid Assembly of Unsymmetrically Linked Bis-heterocycles via Palladium Domino Catalysis

A palladium-catalyzed domino reaction of alkene-tethered oxime esters is reported. This transformation uses an air-stable palladium precatalyst that initiates a Narasaka-Heck reaction, that is interrupted with a Pd(II)-promoted cyclization. Through this methodology, a novel class of unsymmetrical alkyl-linked bis-heterocycles were synthesized in yields up to 99%. The reaction is scalable up to 1.0 mmol, with simplified purification steps. This transformation expands the scope of accessible bis-heterocycles available through Narasaka-Heck reactions beyond C-H activation and direct anionic capture termination steps.

Palladium-Catalyzed Synthesis of Linked Bis-Heterocycles─Synthesis and Investigation of Photophysical Properties

A palladium-catalyzed domino C-N coupling/Cacchi reaction is reported. Design of photoluminescent bis-heterocycles, aided by density functional theory calculations, was performed with synthetic yields up to 98%. The photophysical properties of the products accessed via this strategy were part of a comprehensive study that led to broad emission spectra and quantum yields of up to 0.59. Mechanistic experiments confirmed bromoalkynes as competent intermediates, and a density functional theory investigation suggests a pathway involving initial oxidative addition into the cis C-Br bond of the gem-dihaloolefin.

[Trauma emergency room cases before and during the COVID-19 pandemic : Data from an alpine trauma center]

INTRODUCTION

The COVID-19 pandemic had a strong impact on the work of trauma medical teams. The aim of the study was to compare the trauma emergency room (TER) incidence and trauma mechanisms before and during the pandemic at a level I trauma center.

OBJECTIVE

The TER incidence before and during the pandemic should be assessed to be prepared for future pandemics or new COVID-19 outbreaks.

MATERIAL AND METHODS

Medical charts from all TER patients from March 2019 to February 2021 were analyzed. The incidence and trauma mechanisms of the 12 months before and the 12 months during the pandemic were compared. The trauma distribution and severity were described by the AIS and ISS, and the patients' country of residency was noted.

RESULTS

The TER cases decreased from 694 before the COVID-19 pandemic to 477 cases during the pandemic (Incidence rate 0.69). The strongest decrease in trauma cases was noted in sports injuries (0.55), followed by suicide attempts (0.63), traffic accidents (0.71) and leisure accidents (0.76). The rate of patients with severe injuries (ISS ≥ 16) was comparable with 40% before the pandemic and 44% during the pandemic. Foreign residency of TER patients shifted from 37% before the pandemic to 16% during the pandemic. The number of foreign patients was significantly reduced during the pandemic (257 vs. 77).

DISCUSSION

The TER incidence significantly decreased during the pandemic due to the imposed lockdowns during the peak winter tourism season. The rate of foreign TER patients changed during the pandemic, while the rate of severely injured patients remained stable.

Raman spectroscopy for postmortem interval estimation of human skeletal remains: A scoping review

Estimating postmortem intervals (PMI) is crucial in forensic investigations, providing insights into criminal cases and determining the time of death. PMI estimation relies on expert experience and a combination of thanatological data and environmental factors but is prone to errors. The lack of reliable methods for assessing PMI in bones and soft tissues necessitates a better understanding of bone decomposition. Several research groups have shown promise in PMI estimation in skeletal remains but lack valid data for forensic cases. Current methods are costly, time-consuming, and unreliable for PMIs over 5 years. Raman spectroscopy (RS) can potentially estimate PMI by studying chemical modifications in bones and teeth correlated with burial time. This review summarizes RS applications, highlighting its potential as an innovative, nondestructive, and fast technique for PMI estimation in forensic medicine.

BF3-Catalyzed Intramolecular Fluorocarbamoylation of Alkynes via Halide Recycling

A BF₃-catalyzed atom-economical fluorocarbamoylation reaction of alkyne-tethered carbamoyl fluorides is reported. The catalyst acts as both a fluoride source and Lewis acid activator, thereby enabling the formal insertion of alkynes into strong C-F bonds through a halide recycling mechanism. The developed method provides access to 3-(fluoromethylene) oxindoles and γ-lactams with excellent stereoselectivity, including fluorinated derivatives of known protein kinase inhibitors. Experimental and computational studies support a stepwise mechanism for the fluorocarbamoylation reaction involving a turnover-limiting cyclization step, followed by internal fluoride transfer from a BF₃-coordinated carbamoyl adduct. For methylene oxindoles, a thermodynamically driven Z-E isomerization is facilitated by a transition state with aromatic character. In contrast, this aromatic stabilization is not relevant for γ-lactams, which results in a higher barrier for isomerization and the exclusive formation of the Z-isomer.

Raman microscopic spectroscopy as a diagnostic tool to detect Staphylococcus epidermidis in bone grafts

INTRODUCTION

Raman microscopic spectroscopyis a new approach for further characterization and detection of molecular features in many pathological processes. This technique has been successfully applied to scrutinize the spatial distribution of small molecules and proteins within biological systems by in situ analysis. This study uses Raman microscopic spectroscopyto identify any in-depth benefits and drawbacks in diagnosing Staphylococcus epidermidis in human bone grafts.

MATERIAL AND METHODS

40 non-infected human bone samples and 10 human bone samples infected with Staphylococcus epidermidis were analyzed using Raman microscopic spectroscopy. Reflectance data were collected between 200 cm^-1 and 3600 cm^-1 with a spectral resolution of 4 cm^-1 using a Senterra II microscope (Bruker, Ettlingen, Germany). The acquired spectral information was used for spectral and unsupervised classification, such as principal component analysis.

RESULTS

Raman measurements produced distinct diagnostic spectra that were used to distinguish between non-infected human bone samples and Staphylococcus epidermidis infected human bone samples by spectral and principal component analyses. A substantial loss in bone quality and protein conformation was detected by human bone samples co-cultured with Staphylococcus epidermidis. The mineral-to-matrix ratio using the phosphate/Amide I ratio (p = 0.030) and carbonate/phosphate ratio (p = 0.001) indicates that the loss of relative mineral content in bones upon bacterial infection is higher than in non-infected human bones. Also, an increase of alterations in the collagen network (p = 0.048) and a decrease in the structural organization and relative collagen in infected human bone could be detected. Subsequent principal component analyses identified Staphylococcus epidermidis in different spectral regions, respectively, originating mainly from CH₂ deformation (wagging) of protein (at 1450 cm^-1) and bending and stretching modes of C-H groups (∼2800-3000 cm^-1).

CONCLUSION

Raman microscopic spectroscopyis presented as a promising diagnostic tool to detect Staphylococcus epidermidis in human bone grafts. Further studies in human tissues are warranted.

Visible and Near-Infrared hyperspectral imaging (HSI) can reliably quantify CD3 and CD45 positive inflammatory cells in myocarditis: Pilot study on formalin-fixed paraffin-embedded specimens from myocard obtained during autopsy

INTRODUCTION

To implement Hyperspectral Imaging (HSI) as a tool for quantifying inflammatory cells in tissue specimens by the example of myocarditis in a collective of forensic patients.

MATERIAL AND METHODS

44 consecutive patients with suspected myocardial inflammation at autopsy, diagnosed between 2013 and 2018 at the Institute of ForensicMedicine, Medical University of Innsbruck, were selected for this study. Using the IMEC SNAPSCAN camera, visible and near infrared hyperspectral images were collected from slides stained with CD3 and CD45 to assess quantity and spatial distribution of positive cells. Results were compared with visual assessment (VA) and conventional digital image analysis (DIA).

RESULTS

Finally, specimens of 40 patients were evaluated, of whom 36 patients (90%) suffered from myocarditis, two patients (5%) had suspected healing/healed myocarditis, and two did no have myocarditis (5%). The amount of CD3 and CD45 positive cells did not differ significantly between VA, HSI, and DIA (p^VA/HSI/DIA = 0.46 for CD3 and 0.81 for CD45). Coheńs Kappa showed a very high correlation between VA versus HSI, VA versus DIA, and HSI versus DIA for CD3 (Coheńs Kappa = 0.91, 1.00, and 0.91, respectively). For CD45 an almost as high correlation was seen for VA versus HSI and HSI versus DIA (Coheńs Kappa = 0.75 and 0.70) and VA versus DIA (Coheńs Kappa = 0.89).

CONCLUSION

HSI is a reliable and objective method to count inflammatory cells in tissue slides of suspected myocarditis. Implementation of HSI in digital pathology might further expand the possibility of a sophisticated method.

Accessing Unsymmetrically Linked Heterocycles through Stereoselective Palladium-Catalyzed Domino Cyclization

A palladium-catalyzed strategy is presented to synthesize unsymmetrically linked heterocycles within stereoselective tetrasubstituted olefins. This reaction is proposed to occur via a vinyl-Pd^II intermediate capable of initiating the cyclization of various alkyne-tethered nucleophiles. Products are formed in up to 96 % yield and excellent stereoselectivities are obtained using low catalyst loadings. This transformation was scalable up to 1 mmol and mechanistic studies suggest a syn-carbopalladation of the carbamoyl chloride followed by Pd^II -catalyzed cyclization of alkyne-tethered nucleophiles.

Some Indian herbs have protective effects against deleterious effects of ochratoxin A in broiler chicks

A protective effect of two herbs, Glycyrrhiza glabra and Tinospora cordifolia, given as feed additives was observed against the growth inhibitory effect of ochratoxin A (OTA) and associated immunosuppression and biochemical or pathomorphological changes. The feed levels of 3 mg/kg OTA and fine powder of one of both herbs were given during a period of 32 days to female broiler chicks divided into 3 experimental and 1 control groups (14 chicks per group). The observed pathological and biochemical changes, the changes in relative organs’ weight and body weight, and the decrease of antibody titer against Newcastle disease were more pronounced in the OTA-treated chicks without herbal supplementation, and less pronounced in the chicks treated additionally with G. glabra or T. cordifolia as was shown by the better feed performance and the higher body weight in the chicks treated with the herbs. The higher relative weight of lymphoid organs of the chicks supplemented with both herbs revealed their beneficial effects on the immune system. The hepatoprotective effect of both herbs was evident, being stronger in the chicks additionally supplemented with G. glabra shown by the pathomorphological findings and by the lower levels of aspartate transaminase (131.1 U/l) compared to chicks given only OTA (156.0 U/l). A protective effect of T. cordifolia on the bone marrow and kidneys was found as was shown by the lower levels of uric acid (382.9 μmol/l) compared to chicks given only OTA (466.9 μmol/l).

Synthesis of 1-Amino-2,2,2-trifluoroalkylphosphonates from Alkene-Tethered Trifluoroacetimidoyl Chlorides

The reaction of alkene-tethered trifluoroacetimidoyl chlorides with trialkyl phosphites furnishes 1-amino-2,2,2-trifluoroalkylphosphonates. The products were generated in moderate to good yields, and the scalability of this process was showcased. Partial hydrolysis of the phosphonate moiety was achieved. The cyclization is proposed to occur via formation of an imidoyl phosphonate intermediate that becomes susceptible to nucleophilic attack at nitrogen through the strong electron-withdrawing groups at the imidoyl carbon.

Sequential Pd0 - and PdII -Catalyzed Cyclizations: Enantioselective Heck and Nucleopalladation Reactions

An enantioselective consecutive cyclization/coupling process, catalyzed by palladium is reported. Stereoinduction arises from an enantioselective carbopalladation, generating an intermediate which promotes a nucleopalladation step. The dual cyclization sequence was compatible with a variety of alkyne-tethered oxygen- and nitrogen-centered nucleophiles, and a variety of alkenyl-tethered aryl iodides, to forge numerous bisheterocycles in good yields and high regio- and enantioselectivities.

Imaging in gynecological disease (21): clinical and ultrasound characteristics of accessory cavitated uterine malformations

OBJECTIVE

To describe the clinical and ultrasound characteristics of accessory cavitated uterine malformations (ACUMs).

METHODS

This was a single-center observational study of consecutive patients diagnosed with an ACUM, who had undergone an ultrasound examination by an experienced ultrasound examiner between January 2013 and May 2019, identified retrospectively from medical records. ACUM was diagnosed when a cavitated lesion with a myometrial mantle and echogenic contents was seen within the anterolateral wall of the myometrium beneath the insertion of the round ligament. In all women, presenting symptoms and clinical history were recorded along with detailed descriptions of the lesions and any concomitant pelvic abnormalities.

RESULTS

Twenty patients diagnosed with an ACUM were identified. Median age was 29.2 (interquartile range, 25.0-35.8) years. None of the women was premenarchal or postmenopausal. All of the women reported painful periods or pelvic pain and none of them reported subfertility. Twelve of the ACUMs were in the right anterolateral myometrium and eight were in the left anterolateral myometrium. Both a myometrial mantle and a fluid-filled cavity were considered to be defining features on ultrasound. The fluid contained within the cavity was either echogenic with a ground-glass appearance or hyperechoic. All of the lesions were spherical in shape. The Doppler flow seen in the outer rim was not markedly different from that of the surrounding myometrium, and the content of the cavity was avascular on Doppler examination. The mean outer cavity diameter of the ACUMs was 22.8 (95% CI, 20.9-24.8) mm and the mean internal cavity diameter was 14.1 (95% CI, 12.2-16.1) mm. Four women opted for transvaginal ultrasound-guided alcohol sclerotherapy. Surgical excision was carried out in eight cases, and the diagnosis was confirmed on histopathological examination in all of them.

CONCLUSIONS

ACUMs are a uterine abnormality with a distinct ultrasound appearance, which are associated with dysmenorrhea and chronic pelvic pain. Knowledge of their typical appearance on ultrasound could facilitate early detection and treatment. There are several treatment options for ACUM, ranging from simple analgesia to complete excision. Further prospective and longitudinal studies are required to study the prevalence and natural history of this condition. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Intercellular bridges coordinate the transition from pluripotency to meiosis in mouse fetal oocytes

Meiosis is critical to generating oocytes and ensuring female fertility; however, the mechanisms regulating the switch from mitotic primordial germ cells to meiotic germ cells are poorly understood. Here, we implicate intercellular bridges (ICBs) in this state transition. We used three-dimensional in toto imaging to map meiotic initiation in the mouse fetal ovary and revealed a radial geometry of this transition that precedes the established anterior-posterior wave. Our studies reveal that appropriate timing of meiotic entry across the ovary and coordination of mitotic-meiotic transition within a cyst depend on the ICB component Tex14, which we show is required for functional cytoplasmic sharing. We find that Tex14 mutants more rapidly attenuate the pluripotency transcript Dppa3 upon meiotic initiation, and Dppa3 mutants undergo premature meiosis similar to Tex14 Together, these results lead to a model that ICBs coordinate and buffer the transition from pluripotency to meiosis through dilution of regulatory factors.

33 Diagnostic Test Accuracy of the 4AT for Delirium Detection: Systematic Review and Meta-Analysis

Introduction

Detection of delirium in hospitalised older adults is recommended in national and international guidelines. The 4 ‘A’s Test (4AT; www.the4AT.com) is a short (<2 min) instrument for delirium detection that is used internationally as a standard tool in clinical practice. We performed a systematic review and meta-analysis of diagnostic test accuracy of the 4AT for delirium detection.

Methods

We searched the following electronic databases through Ovid: MEDLINE, Embase, and PsycINFO. Additional databases were searched: CINAHL (EBSCOhost), clinicaltrials.gov and Cochrane Central Register of Controlled Trials from 2011 (4AT publication) until 21 December 2019. Inclusion criteria: older adults (≥65) across any setting of care except critical care; validation study of the 4AT against a delirium reference standard (standard diagnostic criteria or validated tool). Two reviewers independently screened abstracts and papers and performed the data extraction. Pooled estimates of sensitivity and specificity were generated from a bivariate random effects model.

Results

17 studies (n = 3,701 observations) were included. Various settings including acute medicine, surgery, stroke wards and the emergency department were represented. The overall prevalence of delirium was 24.2% (95% CI 17.8–32.1%; range 10.5–61.9%). The pooled sensitivity was 0.88 (95% CI 0.80–0.93) and the pooled specificity was 0.88 (95% CI 0.82–0.92). The methodological quality of studies was mostly good.

Conclusions

The 4AT is now supported by a substantial evidence base comparable to other well-studied tools such as the Confusion Assessment Method (CAM). The strong pooled sensitivity and specificity findings for the 4AT in this meta-analysis along with its brevity and lack of need for specific training provide support for its use as an effective assessment tool for delirium.

Mid-term follow-up of surgically treated and healed scaphoid fractures

The aim of this study was to evaluate the mid-term results of surgically treated scaphoid fractures since we were concerned that good results might deteriorate over time due to osteoarthritis or functional impairment. Thirty-three out of 121 surgically treated patients (isolated scaphoid fractures n = 23; scaphoid fractures with concomitant injuries n = 10) were evaluated retrospectively (47-138 months). Five patients (4%) had a non-union after internal fixation and were excluded because of additional treatment. The remaining 83 patients were not available for a follow-up examination. Patients with an isolated scaphoid fracture had a mean extension-flexion of 68°-0°-64°, a radial-ulnar deviation of 27°-0°-41° and a grip strength of 39 kg (corresponding to 87-98% of the uninjured contralateral wrist), while patients with concomitant injuries had a mean extension-flexion of 60°-0°-44°, radial-ulnar deviation of 22°-0°-38° and a grip strength of 42 kg (corresponding to 73-98% of the uninjured contralateral wrist). The Michigan Hand Questionnaire score was 85 and 75 and the Patient-Rated Wrist Evaluation score was 8 and 21, respectively. Fifteen patients had radiological signs of radiocarpal osteoarthritis with a significantly higher occurrence in those who had concomitant injuries compared to those with isolated scaphoid fractures (p < 0.01). There was no significant group difference in scaphotrapeziotrapezoid (STT) osteoarthritis (p = 0.968). One STT osteoarthritis case occurred after plate fixation, one after antegrade screw fixation and 10 after retrograde screw fixation. Surgical treatment of an acute isolated scaphoid fracture has excellent clinical, functional, and radiologic mid-term results, while scaphoid fractures with concomitant wrist injuries have slightly inferior results.

Implementing changes to a residency program curriculum before competency-based medical education: a survey of Canadian medical oncology program directors

Background

Postgraduate medical education is undergoing a paradigm shift in many universities worldwide, transitioning from a time-based model to competency-based medical education (cbme). Residency programs might have to alter clinical rotations, educational curricula, assessment methods, and faculty involvement in preparation for cbme, a process not yet characterized in the literature.

Methods

We surveyed Canadian medical oncology program directors on planned or newly implemented residency program changes in preparation for cbme.

Results

Prior to implementing cbme, all program directors changed at least 1 clinical rotation, most commonly making hematology/oncology (74%) entirely outpatient and eliminating radiation oncology (64%). Introductory rotations were altered to focus on common tumour sites, and later rotations were changed to increase learner autonomy. Most program directors planned to enhance resident learning with electronic teaching modules (79%), new training experiences (71%), and academic half-day changes (50%). Most program directors (64%) planned to change assessment methods to be entirely based on entrustable professional activities. All programs had developed a competence committee to review learner progress, and most (86%) had integrated academic coaches.

Conclusions

Transitioning to cbme led to major structural and curricular changes within medical oncology training programs. Identifying these commonly implemented changes could help other programs transition to cbme.

Improving formative assessments in Canadian medical oncology residency training

Medical oncology is a subspecialty of internal medicine that involves the treatment of cancer with a variety of complex systemic therapies [...]

Neurovascular Complications in COVID-19 Infection: Case Series

We present a series of 10 hospitalized patients with confirmed coronavirus 2019 infections who developed severe neurovascular complications and discuss the possible reasons for these findings and their relationship to the novel Severe Acute Respiratory Syndrome coronavirus 2 infection.

Panitumumab-induced pulmonary toxicity

Mutations in EGFR have been implicated in the pathogenesis of various types of cancer, and therefore antibody therapy directed against the epidermal growth factor receptor (egfr) is increasingly being used in the management of various cancers. Currently, anti-egfr antibodies are used mainly in the management of cancers of the head and neck and metastatic colorectal cancers. Because of this increasing use, we would like to inform the oncology community in North America of a rare, but life-threatening, toxicity associated with anti-egfr antibody therapy. Although cases in white and Japanese men have been documented, we present the first known North American report of panitumumab-induced pulmonary toxicity in a white woman.

Families of Children Newly Diagnosed With Cancer Incur Significant Out-of-Pocket Expenditure for Treatment: Report of a Multi-Site Prospective Longitudinal Study From India (INPOG-ACC-16-01)

Background: Diagnosis of cancer in a child places considerable economic burden on families. The health expenditures are more catastrophic in resource limited countries like India where GDP spend on health is just over 1% and financing of treatment is usually out-of-pocket (OOP). Consequently parents may abandon their child's cancer treatment to ensure financial sustainability of the family. Research in this area is mostly from resource rich countries and OOP expenditure burden remains unknown in India. Aim: The objective of this study is to describe the OOP expenditure incurred by families of children (< 18 years age) with cancer being treated in India prior to and during cancer directed treatment. Methods: A prospective cost of illness study from a family household perspective was conducted in 14 centers (5 public, 5 private and 4 charitable trust sector) in 4 cities in India from 2016-2018. Baseline family demographic and socioeconomic data were collected followed by OOP expenditure incurred prior to start of treatment. For the duration of the child's treatment, a social worker contacted parents at regular intervals to record their expenditure on cancer directed treatment. Data collection was stopped when one of these happened - completion of treatment or death or progression/relapse or abandonment or transfer. Data were described descriptively and a univariate/multivariate analysis using logistic regression was done to detect factors associated with OOP expenditure. Results: 394 children (63% male, median age 5 years) with cancer (64% leukemia/lymphoma, 33% solid tumors, 3% CNS tumors) were enrolled from public (45%), charitable trust (28%) and private (27%) sector hospitals. They were symptomatic for a median duration of 6 weeks (range 0 to 104 weeks). 88% had no insurance and 73% were from families with monthly income of ≤ 10,000 rupees (≤ 159 US$). Mean OOP expenditure was Rs 209,500 (3325 US$) which is 195% of per capita income (1706 US$) of India. OOP expenditure from onset of symptoms to start of treatment was Rs 53,104 (843 US$) of which 77% was medical (15% laboratory tests, 11% medicines, 9% hospital bed costs) and 23% nonmedical (12% travel, 6% food, 3% lodging). OOP expenditure on cancer directed treatment was Rs 156,396 (2482 US$) of which 64% was medical (9% hospital bed costs, 9% supportive care drugs, 8% laboratory tests) and 36% nonmedical (19% food, 9% travel, 6% lodging). On univariate analysis age, gender, city, type of treatment facility, insurance, type of cancer, driving time and distance were significantly associated with OOP expenditure but only insurance and type of treatment facility were found significant on multivariate analysis. Conclusion: Families of children with cancer incur significant OOP expenditure prior to and during cancer directed treatment, which includes a significant portion on nonmedical expenses. Expenditure varied significantly by insurance and type of treatment facility.

Comparison of volarly and dorsally displaced distal radius fracture treated by volar locking plate fixation

INTRODUCTION

In case of distal radius fractures (DRF) the distal fragment generally displaces either dorsally or volarly. Scientific literature however, seldom differentiates between volarly and dorsally displaced DRFs when reporting results. It is no clear, if the direction of displacement has an influence on the clinical and radiological outcome. This study was intended to evaluate the influence of displacement direction in adult patients with surgically treated Colles or Smith type fractures.

PATIENTS AND METHODS

After a mean follow up (FU) time of above 5 years, 50 patients who underwent open reduction and internal fixation for DRFs (25 Smith type fractures, 25 Colles type fractures) were included. Upon FU, standard X-rays and a clinical evaluation as well as evaluation scores were raised and analysed.

RESULTS

Clinical evaluation showed no difference between the Colles and the Smith group. Radiologic and clinical results for the Colles group showed diminished flexion compared to the healthy wrist, decreased radial inclination and dorsal tilt during FU and progression of osteoarthritis. For the Smith group decreased grip strength compared to the healthy wrist and osteoarthritis-progression was found. For both groups there was no correlation between radiologic values, grip strength, arthrosis grading, disability of arm, shoulder and hand score and patient rated wrist evaluation score.

DISCUSSION

Decreased flexion in combination with a decreased dorsopalmar tilt might hint towards a mechanical inhibition in the Colles group. Altogether, the study showed good clinical outcome with satisfactory radiological result. As all patients showed arthrosis progression, the fracture per se is to be seen as a prearthrotic factor. It still remains unclear which measures could be taken to prevent this.

Differential promoter methylation of DAZL gene in bulls with varying seminal parameters

In India, cross-breeding of indigenous cattle with exotic cattle such as Holstein Friesian and Jersey has been going on since last four decades to improve milk production. Although it has led to increased milk yield, the subfertility in male cross-bred progeny has remained a significant problem. Epigenetic modifications (DNA methylation, histone modifications and chromatin remodelling) are regarded as key players influencing gene expression. DAZL gene plays an important role in germline development and gametogenesis. The methylation and mRNA expression level of this gene have been significantly negatively correlated in the testes of cattle-yak hybrids and their parents. This study analysed the methylation profile of DAZL gene promoter in bull spermatozoa in an attempt to speculate its role in cross-bred cattle subfertility. Semen samples from Sahiwal, Holstein Friesian and Frieswal bulls (Sahiwal X Holstein Friesian) with varying semen motility parameters were collected, and DNA was isolated. Methylation-specific primers were used to amplify part of promoter and exon 1 of DAZL gene using bisulphite-converted DNA. The amplified products were sequenced after cloning in pTZ57R/T vector. Sequence analysis revealed significantly higher DNA methylation of DAZL gene in Frieswal bulls with poor motility (28.26%) as compared to medium (15.21%) and high motility phenotype (6.52%). In pure-bred counterparts, Sahiwal and Holstein Friesian, epigenetic marks were more in the former (15.21%) than the latter (4.34%), but in both cases, the values were lower as compared to the poor motility Frieswal bulls. This suggests that differential hypermethylation of the CpG islands could possibly influence reproductive parameters in bovines.

Biomechanical in vitro comparison of suture anchors for thumb UCL repair

Different types of intraosseous suture anchors can be used for thumb ulnar collateral ligament (UCL) repair surgery. Some of them have already been tested biomechanically in intact bone; however, there exists little knowledge of their stability when implanted in avulsion fracture. In this biomechanical in vitro study, three anchor types (hard, soft and novel BoneWelding) were tested on 24 fresh frozen human thumbs from 12 body donors. After the repair of an iatrogenic ligamentous UCL rupture, the thumbs were cyclically loaded. A new set of anchors was implanted at the contralateral radial side of the same specimen into an iatrogenic avulsion fracture and pulled out of the bone. The most common mode of failure in ligamentous UCL repairs was the suture-ligament interface, especially when using soft anchors. In avulsion fractures, the novel anchor withstood significantly higher pullout forces than the hard or soft anchor (65 N vs. 42 N vs. 27 N; p = .006). The BW anchor provides sufficient anchorage in trabecular bone for UCL repair in case of avulsion fractures.