NIR-activated quercetin-based nanogels embedded with CuS nanoclusters for the treatment of drug-resistant biofilms and accelerated chronic wound healing

We have developed multifunctional nanogels with antimicrobial, antioxidant, and anti-inflammatory properties, facilitating rapid wound healing. To prepare the multifunctional nanogels, we utilized quercetin (Qu) and a mild carbonization process to form carbonized nanogels (CNGs). These CNGs possess excellent antioxidative and bacterial targeting properties. Subsequently, we utilized the Qu-CNGs as templates to prepare nanogels incorporating copper sulfide (CuS) nanoclusters, further enhancing their functionality. Notably, the CuS/Qu-CNGs nanocomposites demonstrated an exceptional minimum inhibitory concentration against tested bacteria, approximately 125-fold lower than monomeric Qu or Qu-CNGs. This enhanced antimicrobial effect was achieved by leveraging near-infrared II (NIR-II) light irradiation. Additionally, the CuS/Qu-CNGs exhibited efficient penetration into the extracellular biofilm matrix, eradicating methicillin-resistant Staphylococcus aureus-associated biofilms in diabetic mice wounds. Furthermore, the nanocomposites were found to suppress proinflammatory cytokines, such as IL-1β, at the wound sites while regulating the expression of anti-inflammatory factors, including IL-10 and TGF-β1, throughout the recovery process. The presence of CuS/Qu-CNGs promoted angiogenesis, epithelialization, and collagen synthesis, thereby accelerating wound healing. Our developed CuS/Qu-CNGs nanocomposites have great potential in addressing the challenges associated with delayed wound healing caused by microbial pathogenesis.

Lumbar Spine Injury in Indian Fast Bowlers: 3D Biomechanical Analysis and Prevention Strategies

Background

Lumbar spine injuries are among the most common overuse injuries in a fast bowler. Among various causative factors, bowling action technique is a crucial one. Three-dimensional motion analysis has been accepted as a gold standard tool to identify incorrect techniques. Previous studies have identified key biomechanical variables associated with lumbar injury risk in fast bowlers. Despite the large popularity of the sport, there is limited information available on the subject in Indian fast bowlers. This study aims to analyse the lumbar spine injury risk in Indian fast bowlers with respect to key biomechanical variables, using 3D motion analysis.

Methods

Forty-seven male first class fast bowlers underwent 3D motion analysis in an indoor biomechanics laboratory. Motion capture was done with 3D cameras and 2D video cameras, using a standard marker set. Data processing and analysis was done using proprietary software. Biomechanical variables associated with lumbar spine injury risk including lateral trunk flexion (LTF) and knee angle at front foot contact (KA at FFC) were measured, and peak vertical ground reaction forces (pVGRF) were simultaneously recorded using force plates. Descriptive analysis of the data was done.

Results

26% of bowlers had a high LTF, 29% had low KA at FFC and 43% had high pVGRF. Thus, a large proportion of bowlers in this study were at risk of lumbar spine injury with respect to the assessed variables.

Conclusion

This highlights the role of 3D motion analysis in early identification of injurious techniques, which can be modified by coaching and training interventions to prevent injuries. This study thus has implications on coaching and training of fast bowlers in India.

Prophylaxis for preventing venous thromboembolism in knee arthroscopy and soft tissue reconstruction: consensus statements from an international panel of experts

PURPOSE

There is a lack of consensus regarding need for Venous Thrombo Embolism (VTE) prophylaxis following arthroscopic knee surgery and open soft tissue knee reconstruction. Clear cut guidelines like ones for trauma surgery and arthroplasty do not exist and the published literature is limited to case reports with a few society guidelines. Given this lack of consensus, we conducted a modified Delphi questionnaire of international experts to provide recommendations on this topic.

METHODS

The consensus statements were generated using an anonymised 3 round modified Delphi questionnaire, sent to an international panel of 38 knee surgeons, with an 80% agreement being set as the limit for consensus. The responses were analysed using descriptive statistics with measures like mode, median and box plots. Feedback was provided to all panelists based on responses from the previous rounds to help generate the consensus.

RESULTS

Six consensus statements were generated after the three rounds of Delphi. Patient factors, prolonged surgery duration and family history of thrombogenic events emerged as the main points to be taken into consideration for prophylaxis.

CONCLUSION

It was established through this study, that there exists a select group of patients undergoing arthroscopic surgery that justify the usage of VTE prophylaxis. The expert responses to most of the questions in different scenarios favoured usage of VTE prophylaxis based on patient factors like advanced age, past history of VTE, smoking, oral contraceptive use etc. LEVEL OF EVIDENCE: Level V.

Rac1 activation can generate untemplated, lamellar membrane ruffles

BACKGROUND

Membrane protrusions that occur on the dorsal surface of a cell are an excellent experimental system to study actin machinery at work in a living cell. Small GTPase Rac1 controls the membrane protrusions that form and encapsulate extracellular volumes to perform pinocytic or phagocytic functions.

RESULTS

Here, capitalizing on rapid volumetric imaging capabilities of lattice light-sheet microscopy (LLSM), we describe optogenetic approaches using photoactivable Rac1 (PA-Rac1) for controlled ruffle generation. We demonstrate that PA-Rac1 activation needs to be continuous, suggesting a threshold local concentration for sustained actin polymerization leading to ruffling. We show that Rac1 activation leads to actin assembly at the dorsal surface of the cell membrane that result in sheet-like protrusion formation without any requirement of a template. Further, this approach can be used to study the complex morpho-dynamics of the protrusions or to investigate specific proteins that may be enriched in the ruffles. Deactivating PA-Rac1 leads to complex contractile processes resulting in formation of macropinosomes. Using multicolour imaging in combination with these approaches, we find that Myo1e specifically is enriched in the ruffles.

CONCLUSIONS

Combining LLSM and optogenetics enables superior spatial and temporal control for studying such dynamic mechanisms. Demonstrated here, the techniques implemented provide insight into the complex nature of the molecular interplay involved in dynamic actin machinery, revealing that Rac1 activation can generate untemplated, lamellar protrusions.

Rapid whole cell imaging reveals a calcium-APPL1-dynein nexus that regulates cohort trafficking of stimulated EGF receptors

The endosomal system provides rich signal processing capabilities for responses elicited by growth factor receptors and their ligands. At the single cell level, endosomal trafficking becomes a critical component of signal processing, as exemplified by the epidermal growth factor (EGF) receptors. Activated EGFRs are trafficked to the phosphatase-enriched peri-nuclear region (PNR), where they are dephosphorylated and degraded. The details of the mechanisms that govern the movements of stimulated EGFRs towards the PNR, are not completely known. Here, exploiting the advantages of lattice light-sheet microscopy, we show that EGFR activation by EGF triggers a transient calcium increase causing a whole-cell level redistribution of Adaptor Protein, Phosphotyrosine Interacting with PH Domain And Leucine Zipper 1 (APPL1) from pre-existing endosomes within one minute, the rebinding of liberated APPL1 directly to EGFR, and the dynein-dependent translocation of APPL1-EGF-bearing endosomes to the PNR within ten minutes. The cell spanning, fast acting network that we reveal integrates a cascade of events dedicated to the cohort movement of activated EGF receptors. Our findings support the intriguing proposal that certain endosomal pathways have shed some of the stochastic strategies of traditional trafficking and have evolved processes that provide the temporal predictability that typify canonical signaling.

The switchable phase transition of sodium sulfate crystals activated by shock waves

A shock-wave-induced reversible phase-transformation from phase-V to phase-III of Na2SO4 is achieved, and the results are evidenced via XRD and Raman spectroscopy.

Spectroscopic assessment on the stability of benzophenone crystals at shock waves loaded condition

In recent years, there have been few thousands of non-linear optical (NLO) materials proposed for a wide array of technological applications. But unfortunately, most of the materials do not fit into the actual standard required for the specific purposes in terms of their efficiency, environmental resistance, cost effectiveness, availability, stability and durability. Hence, searching for the most suitable material for every specific technological application has become the necessity of being a continuous process until it is found. For the present experiment, we have chosen benzophenone crystal for the shock wave recovery experiment. Raman and powder X-ray diffraction (XRD) techniques have been utilized to evaluate the molecular and structural performances of the title material against the impact of shock waves and the obtained crystallographic structural properties are compared with potassium dihydrogen phosphate (KPD) crystal. The obtained Raman and XRD results demonstrate that the title material has high shock resistant property even though it is a mechanically soft material as well as it has very low melting point (48 °C).

Evaluation of regeneration of semitendinosus tendon using ultrasound imaging and isokinetic strength testing after graft harvest for arthroscopic anterior cruciate ligament reconstruction

Background

A lot of the research has been done worldwide evaluating the capacity of the semitendinosus tendon to regenerate which has not been conducted in the Indian population.

Study design

31 patients who underwent unilateral ACL reconstruction with hamstrings were taken into study. All patients underwent ultrasonography imaging of both knees and bilateral isokinetic flexion strength assessment at a one-year postoperative period. Images were obtained at three levels and their dimensions are compared with normal side. Isokinetic testing of the knee is done to evaluate the flexion deficit and is compared to the uninvolved knee.

Results

Out of a total of 31 patients, 14 patients showed no regeneration, 17 showed regeneration at various levels. On isokinetic testing patients with no regeneration showed the highest mean flexion deficit.

Conclusion

The semitendinosus tendon and its regeneration can be visualized well using ultrasonography. After semitendinosus harvesting, the flexion strength will be decreased as compared to the normal knee. The flexion strength in patients who have a regenerated tendon will be higher as compared to those who have no regeneration.

Knee flexion strength deficits correlate with distal extent of tendon regeneration after hamstring harvest. Preliminary data from an Ultrasound based classification

BACKGROUND

As more evidence comes to light that hamstring harvesting may not be as benign a procedure as previously thought, considerable interest is being generated towards corelating the knee flexural strength deficits with the degree of tendon regeneration. The current study aimed to corelate knee flexion strength deficits with ultrasonographically quantified degree of hamstring regeneration after tendon harvest.

STUDY DESIGN

31 patients of ACL reconstruction with hamstring grafts were divided into 2 groups (6 months and 1-year post op) according to time of follow up. Ultrasonography of both the knees to assess Semitendinosus tendon dimensions was done. Regeneration was classified as non-significant, mild (Zone 1, till 4 cm above the lateral joint line), moderate (Zone 2 ,at the level of the lateral joint line) and significant (Zone 3, 1.5 cm below the lateral joint line) as the regenerate happens from proximal to distal. Regenerate dimensions were compared with US measurements from the opposite knee. Bilateral isokinetic strength tests of the knees were done to evaluate flexion strength, and strength deficits were compared with degree of tendon regeneration.

RESULTS

14 (45%) of cases had no regeneration at both time periods. 7 patients (41%) in the 6-month post-op group showed some form of regeneration, and 10 patients (71%) in the 1-year post-op group showed regeneration. 29/31 patients had some flexion strength deficit. Strength deficit correlated with the level and degree of tendon regeneration, with non-significant regeneration cases showing higher strength deficit (mean - 28.51%), and cases with significant regeneration showing least amount of strength deficit (mean - 3.66%).

CONCLUSION

Flexion strength deficits after hamstring harvest are significant and corelate with degree of tendon regeneration, which improves over time. US is adequate to quantify degree of tendon regeneration, which in turn can help prognosticate return of flexion strength.

Influence of pressure on the transport, magnetic, and structural properties of superconducting Cr0.0009NbSe2 single crystal

We investigate the superconducting critical current density (J _c), transition temperature (T _c), and flux pinning properties under hydrostatic pressure (P) for Cr_0.0009NbSe₂ single crystal. The application of P enhances T _c in both electrical resistivity (∼0.38 K GPa^-1: 0 ≤ P ≤ 2.5 GPa) and magnetization (∼0.98 K GPa^-1: 0 ≤ P ≤ 1 GPa) measurements, which leads to a monotonic increase in J _c and flux pinning properties. The field-dependent J _c at various temperatures under P is analyzed within the collecting pinning theory and it shows that δT _c pinning is the crossover to δl pinning above the critical pressure (P _c ∼0.3 GPa). Our systematic analysis of the flux pinning mechanism indicates that both the density of pinning centers and pinning forces greatly increase with the application of P, which leads to an enhancement in the vortex state. Structural studies using synchrotron X-ray diffraction under pressure illustrate a stable hexagonal phase without any significant impurity phase and lattice parameter reduction with P shows highly anisotropic nature.

Understanding pretreatment loss to follow-up of tuberculosis patients: an explanatory qualitative study in Chennai, India

Introduction

Pretreatment loss to follow-up (PTLFU)-dropout of patients after diagnosis but before treatment registration-is a major gap in tuberculosis (TB) care in India and globally. Patient and healthcare worker (HCW) perspectives are critical for developing interventions to reduce PTLFU.

Methods

We tracked smear-positive TB patients diagnosed via sputum microscopy from 22 diagnostic centres in Chennai, one of India's largest cities. Patients who did not start therapy within 14 days, or who died or were lost to follow-up before official treatment registration, were classified as PTLFU cases. We conducted qualitative interviews with trackable patients, or family members of patients who had died. We conducted focus group discussions (FGDs) with HCWs involved in TB care. Interview and FGD transcripts were coded and analysed with Dedoose software to identify key themes. We created categories into which themes clustered and identified relationships among thematic categories to develop an explanatory model for PTLFU.

Results

We conducted six FGDs comprising 53 HCWs and 33 individual patient or family member interviews. Themes clustered into five categories. Examining relationships among categories revealed two pathways leading to PTLFU as part of an explanatory model. In the first pathway, administrative and organisational health system barriers-including the complexity of navigating the system, healthcare worker absenteeism and infrastructure failures-resulted in patients feeling frustration or resignation, leading to disengagement from care. In turn, HCWs faced work constraints that contributed to many of these health system barriers for patients. In the second pathway, negative HCW attitudes and behaviours contributed to patients distrusting the health system, resulting in refusal of care.

Conclusion

Health system barriers contribute to PTLFU directly and by amplifying patient-related challenges to engaging in care. Interventions should focus on removing administrative hurdles patients face in the health system, improving quality of the HCW-patient interaction and alleviating constraints preventing HCWs from providing patient-centred care.

Electrosynthesis of carbon aerogel-modified AuNPs@quercetin via an environmentally benign method for hydrazine (HZ) and hydroxylamine (HA) detection

An ultrasensitive electrochemical sensor fabricated using a hydrothermal and environmentally benign methods for the detection of environmental pollutions, namely, hydrazine (HZ) and hydroxylamine (HA) has been described.

Cordia diffusa K.C. Jacob, the Kovai Manjack (Boraginaceae): a highly threatened steno-endemic species from Coimbatore City, Tamil Nadu, India

Cordia diffusa K.C. Jacob, belonging to Boraginaceae, discovered in 1938 and named by K.C. Jacob in 1944, is a little-known and the only narrow endemic but neglected plant of Coimbatore City.  The lectotype of the steno-endemic is determined and the current status, distribution, potential threats, bioprospecting potential, and suggestions for conservation of the species are discussed.  The collection of steno-endemic plant during intensive exploration in its type locality nearly after 90 years is of phytogeographic and conservation significance.  The endemic is proposed the category of Critically Endangered (CR) based on criterion D of IUCN (as per versions 3.1 & 13).  C. diffusa can be protected by promoting awareness of the rarity of native species and mass propagation through vegetative means so as to introduce it in gardens, parks, and avenues, etc. at once in the city. 

Cordia diffusa K.C. Jacob, the Kovai Manjack (Boraginaceae): a highly threatened steno-endemic species from Coimbatore City, Tamil Nadu, India

Cordia diffusa K.C. Jacob, belonging to Boraginaceae, discovered in 1938 and named by K.C. Jacob in 1944, is a little-known and the only narrow endemic but neglected plant of Coimbatore City.  The lectotype of the steno-endemic is determined and the current status, distribution, potential threats, bioprospecting potential, and suggestions for conservation of the species are discussed.  The collection of steno-endemic plant during intensive exploration in its type locality nearly after 90 years is of phytogeographic and conservation significance.  The endemic is proposed the category of Critically Endangered (CR) based on criterion D of IUCN (as per versions 3.1 & 13).  C. diffusa can be protected by promoting awareness of the rarity of native species and mass propagation through vegetative means so as to introduce it in gardens, parks, and avenues, etc. at once in the city.