Dissolving microneedles for transdermal drug delivery in cancer immunotherapy

Immunotherapy is an important approach in cancer treatment. Transdermal administration is emerging as a promising method for delivering immunotherapeutics. Dissolving microneedles are made mainly of soluble or biodegradable polymers and have garnered widespread attention due to their painlessness, safety, convenience, excellent drug loading capacity, and easy availability of various materials, making them an ideal transdermal delivery system. This review comprehensively summarized the preparation methods, materials, and applications of dissolving microneedles in cancer vaccines, immune checkpoint inhibitors, and adoptive cell therapy. Additionally, the challenges and perspectives associated with their future clinical translation are discussed.

In vivo assessment of dual-function submicron textured nitric oxide releasing catheters in a 7-day rabbit model

Catheter-induced thrombosis is a major contributor to infectious and mechanical complications of biomaterials that lead to device failure. Herein, a dualfunction submicron textured nitric oxide (NO)-releasing catheter was developed. The hemocompatibility and antithrombotic activity of vascular catheters were evaluated in both 20 h in vitro blood loop and 7 d in vivo rabbit model. Surface characterization assessments via atomic force microscopy show the durability of the submicron pattern after incorporation of NO donor S-nitroso-N-acetylpenicillamine (SNAP). The SNAP-doped catheters exhibited prolonged and controlled NO release mimicking the levels released by endothelium. Fabricated catheters showed cytocompatibility when evaluated against BJ human fibroblast cell lines. After 20h in vitro evaluation of catheters in a blood loop, textured-NO catheters exhibited a 13-times reduction in surface thrombus formation compared to the control catheters, which had 83% of the total area covered by clots. After the 7 d in vivo rabbit model, analysis on the catheter surface was examined via scanning electron microscopy, where significant reduction of platelet adhesion, fibrin mesh, and thrombi can be observed on the NO-releasing textured surfaces. Moreover, compared to relative controls, a 63% reduction in the degree of thrombus formation within the jugular vein was observed. Decreased levels of fibrotic tissue decomposition on the jugular vein and reduced platelet adhesion and thrombus formation on the texture of the NO-releasing catheter surface are indications of mitigated foreign body response. This study demonstrated a biocompatible and robust dual-functioning textured NO PU catheter in limiting fouling-induced complications for longer-term blood-contacting device applications. STATEMENT OF SIGNIFICANCE: Catheter-induced thrombosis is a major contributor to infectious and mechanical complications of biomaterials that lead to device failure. This study demonstrated a robust, biocompatible, dual-functioning textured nitric oxide (NO) polyurethane catheter in limiting fouling-induced complications for longer-term blood-contacting device applications. The fabricated catheters exhibited prolonged and controlled NO release that mimics endothelium levels. After the 7 d in vivo model, a significant reduction in platelet adhesion, fibrin mesh, and thrombi was observed on the NO-releasing textured catheters, along with decreased levels of fibrotic tissue decomposition on the jugular vein. Results illustrate that NO-textured catheter surface mitigates foreign body response.

Macro- and microscopic changes in veins with short-term central venous catheters: an observational autopsy study

BACKGROUND

Centrally inserted central catheters (CICCs) are indispensable in modern healthcare, but unfortunately, come with complications. Catheter-related thrombosis is a well-known complication reported to occur in 5-30% of patients with CICC. There is a paucity of studies that report the incidence of catheter-related thrombosis after the introduction of real-time ultrasound insertion guidance as clinical practice. This study aimed to demonstrate any pathological macro- or microscopic changes in the vein wall associated with CICCs.

METHODS

The study was approved by the Swedish Ethical Review Authority and was conducted at a large university hospital. The study included 12 patients with a short-term CICC who were subject to autopsies. Vessels with inserted catheters were macroscopically and microscopically examined.

RESULTS

In total, seven female and five male patients with a median age of 70 (interquartile range 63-76) were included. With one exception, all patients received routine thromboprophylaxis throughout the period with CICC. Most inserted CICCs were 9.5 French (54%) and were inserted in the internal jugular vein (92%). The median time with CICC was seven days (interquartile range 1.8-20). At autopsy, thrombi were observed in all cases (100%), macroscopically and microscopically, attached to the distal portion of the CICC and/or the adjacent vessel wall. Inflammatory changes in the vessel walls were seen in all cases, and varying degrees of fibrosis were demonstrated in eight cases (67%).

CONCLUSIONS

This autopsy study demonstrated that catheter-related thrombus formation with adjacent inflammatory and fibrotic vessel wall thickening was very common, despite a limited period of catheter use. The consequences of these findings are important, as thrombi may cause pulmonary embolism and possibly lead to catheter-related infections, and since inflammatory and fibrotic vessel wall thickening may evolve into chronic venous stenosis. Furthermore, the findings are a cause of concern, as CICCs are indispensable in modern healthcare and complications may be masked by the general disease that was the indication for CICC insertion.

LIBERATE: a study protocol for midodrine for the early liberation from vasopressor support in the intensive care unit (LIBERATE): protocol for a randomized controlled trial

Background

Intravenous (IV) vasopressors to support hemodynamics are a primary indication for intensive care unit (ICU) admission. Utilization of oral vasopressor therapy may offer an alternative to IV vasopressor therapy in the ICU, thus decreasing the need for ICU admission. Oral vasopressors, such as midodrine, have been used for hemodynamic support in non-critically ill patients, but their evaluation in critically ill patients to potentially spare IV vasopressor therapy has been limited.

Methods

The LIBERATE study will be a multicenter, parallel-group, blinded, randomized placebo-controlled trial. It will recruit adult (i.e., age ≥ 18 years) critically ill patients receiving stable or decreasing doses of IV vasopressors. Eligible patients will be randomized to receive either midodrine 10 mg administered enterally every 8 h or placebo until 24 h post-discontinuation of IV vasopressors. The primary outcome will be ICU length of stay. Secondary outcomes include all-cause mortality at 90 days, hospital length of stay, length of IV vasopressor support, re-initiation of IV vasopressors, rates of ICU readmission, and occurrence of AEs. Health economic outcomes including ICU, hospital and healthcare costs, and cost-effectiveness will be evaluated. Pre-planned subgroup analyses include age, sex, frailty, severity of illness, etiology of shock, and comorbid conditions.

Discussion

LIBERATE will rigorously evaluate the effect of oral midodrine on duration of ICU stay and IV vasopressor support in critically ill patients.

Trial registration

ClinicalTrials.gov NCT05058612. Registered on September 28, 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06115-0.

High incidence of large bore temporary hemodialysis catheter malfunction in patients with COVID-19 related kidney injury

PURPOSE

To evaluate the incidence of large bore hemodialysis catheter malfunction in the setting of COVID-19.

MATERIALS AND METHODS

A retrospective review was performed of all patients who underwent placement of a temporary hemodialysis catheter after developing kidney injury after COVID-19 infection at our institution. Data collected included demographic information, procedure related information, and incidence of replacement due to lumen thrombosis. Groups were compared using students t-test for continuous variables and Fisher's exact test for nominal variables.

RESULTS

Sixty-four patients (43M, mean age 63.2 ± 13.3) underwent placement of temporary hemodialysis catheter placement for kidney injury related to COVID 19 infection. Thirty-one (48.4%) of catheters were placed via an internal jugular vein (IJV) access and 33 (52.6%) of catheters were placed via a common femoral vein (CFV) access. Overall, 15 (23.4%) catheters required replacement due to catheter dysfunction. There were no differences in demographics in patients who required replacement to those who did not (p > 0.05). Of the replacements, 5/31 (16%) were placed via an IJV access and 10/33 (30.3%) were placed via a CFV access (p = 0.18). The average time to malfunction/replacement was 7.8 ± 4.8 days for catheters placed via an IJ access versus 3.4 ± 3.3 days for catheters placed via a CFV access (p = 0.055).

CONCLUSION

A high incidence of temporary dialysis catheter lumen dysfunction was present in patients with COVID-19 infection. Catheters placed via a femoral vein access had more frequent dysfunction with shorter indwelling time.

A case of COVID-19 with superficial thrombophlebitis caused by an indwelling peripheral venous catheter

A local hypercoagulable state caused by SARS-CoV-2 and an indwelling peripheral venous catheter can lead to superficial thrombophlebitis. If the venous catheter is no longer needed during treatment for COVID-19 it should be removed promptly.

Incidence and Risk Factors of Lower-Extremity Deep Vein Thrombosis After Thrombolysis Among Patients with Acute Ischemic Stroke

Background

Deep vein thrombosis (DVT) is common among patients with stroke. However, the incidence of DVT in acute ischemic stroke patients treated with thrombolytic therapy and the risk factors associated with this condition are unknown.

Objective

This study aimed to investigate the incidence and risk factors of DVT after thrombolysis in patients with acute ischemic stroke.

Settings and Methods

We retrospectively reviewed the medical records of all patients with acute ischemic stroke who underwent ultrasonic examination after intravenous thrombolysis between April 2017 and December 2019 at the stroke center of the First Hospital of Jilin University, China. Color duplex ultrasound was used to diagnosis DVT in all patients within 72 h after intravenous thrombolysis. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for DVT.

Results

Overall, 474 patients were included in the study. Of these, 75 (15.8%) developed DVT (95% confidence interval 12.5–19.1). Older age was the risk factor that most significantly affected the development of DVT (p = 0.001). Compared to patients younger than 60 years old, those aged 60–69 years and ≥70 years had a higher risk of DVT, at rates of 2.201 (95% CI: 1.033–4.689; p < 0.05) and 4.241 (95% CI: 2.016–8.922; p < 0.001) times higher, respectively. Patients with higher triglyceride levels (odds ratio 0.545, 95% CI: 0.372–0.799, p = 0.002) and longer activated partial thromboplastin time (OR 0.927, 95% CI: 0.862–0.996, p = 0.040) were less likely to have DVT.

Conclusion

DVT is a common complication among patients undergoing intravenous thrombolysis after acute ischemic stroke. Advanced age may increase the occurrence of DVT to some extent. For these patients, safe antiplatelet therapy should be explored and implemented as soon as possible.

Management of superficial venous thrombosis in unevaluated situations: Cancer, severe renal impairment, pregnancy and post-partum

BACKGROUND

Information is lacking as to the management of patients with superficial venous thrombosis (SVT) whose profile has been excluded from trials, such as patients with active cancer, severe renal impairment, or pregnancy.

OBJECTIVES

To describe the frequency and management of SVT occurring in these situations.

METHODS

We retrospectively analyzed the frequency, management and evolution of all patients with isolated SVT associated with either active cancer, severe renal impairment, or pregnant or postpartum women, diagnosed in 2 university hospital between January 1st, 2015 and December 31st, 2016.

RESULTS

Of the 594 isolated SVTs individualized from the 7941 reports screened, 149 SVTs (105 in the upper extremity, 44 in the lower extremity) were analyzed: 94 (63%) associated with active cancer, 27 (18%) with severe renal impairment and 30 (20%) pregnant or postpartum women. SVT was treated with anticoagulant in 34 (36%) patients with cancer, 3 (11%) patients with severe renal impairment and 19 (63%) pregnant or postpartum women. At 3-month, 16 patients (10.8%) had a further venous thromboembolic event, 8 (5.4%) major bleeding, and 9 (6.1%) died.

CONCLUSION

SVT in patients with active cancer, severe renal impairment and pregnant or postpartum women represents a quarter of isolated SVTs diagnosed. Heterogeneity of treatment patterns mainly affects patients with cancer and severe renal impairment. Poor outcomes, although probably linked to morbidity, call for dedicated research in these specific situations.

Deep vein thrombosis of the upper extremity caused by central venous port in a patient with soft tissue sarcoma: A case report

Deep vein thrombosis (DVT) more commonly occurs in the lower extremities, whereas involvement of the upper extremities is rare. The present case report describes the clinical course of the development and treatment of upper extremity DVT (UEDVT) following insertion of an indwelling central venous (CV) port in a patient with soft tissue sarcoma (STS) of the thigh. A 66-year-old man was referred to our hospital for STS treatment. The indwelling CV port was placed via the left subclavian vein, and two courses of neoadjuvant chemotherapy were administered. Two months after the catheter placement, DVT was detected from the left upper arm to the left internal jugular vein. Anticoagulation therapy with warfarin was started and DVT was undetectable at 5 months after surgery. In conclusion, DVT may occur in cancer patients who undergo treatment with indwelling CV ports. Therefore, screening should be conducted concurrently with surgical resection and chemotherapy for STS.

Regenerating Antithrombotic Surfaces through Nucleic Acid Displacement

Blood-contacting devices are commonly coated with antithrombotic agents to prevent clot formation and to extend the lifespan of the device. However, in vivo degradation of these bioactive surface agents ultimately limits device efficacy and longevity. Here, a regenerative antithrombotic catheter surface treatment is developed using oligodeoxynucleotide (ODN) toehold exchange. ODN strands modified to carry antithrombotic payloads can inhibit the thrombin enzyme when bound to a surface and exchange with rapid kinetics over multiple cycles, even while carrying large payloads. The surface-bound ODNs inhibit thrombin activity to significantly reduce fibrinogen cleavage and fibrin formation, and this effect is sustained after ODN exchange of the surface-bound strands with a fresh antithrombotic payload. This study presents a unique strategy for achieving a continuous antithrombotic state for blood-contacting devices using an ODN-based regeneration method.