Surgical delivery of drug releasing poly(lactic-co-glycolic acid)/poly(ethylene glycol) paste with in vivo effects against glioblastoma

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.     

Congestive Heart Failure: A Case of Protein Misfolding

This article describes an interesting case of a patient presenting with congestive heart failure found to have restrictive cardiomyopathy with initial laboratory evaluation showing hypogammaglobuminemia without a monoclonal band on serum and urine electrophoresis. This case highlights the clinically significant cardiac manifestation caused by protein misfolding, a defect in protein homeostasis. In addition, the utility of a relatively newer laboratory test, serum free light chains as well as the importance of clinical and pathophysiologic correlation is also discussed. We present a relatively uncommon cause of heart disease, cardiac amyloidosis in a patient with a systemic plasma cell dyscrasia, and multiple myeloma.     

Risk factors for tuberculosis in older children and adolescents: a matched case–control study in Recife,Brazil

Background

Tuberculosis is a major disease worldwide and most research focus on risk factors for adults, although there is a marked adolescent peak in incidence. The objective of this study was to identify risk factors for tuberculosis in children aged 7 to 19.

Methods

A case control study matched by age with 169 cases and 477 controls. The study population consisted of adolescents and older children from Recife, Brazil. Cases were individuals diagnosed with tuberculosis in the control programme and controls were selected in the neighborhood of cases. Conditional logistic regression was used to identify risk factors.

Results

Cigarette smoking increased by 50% the risk of tuberculosis but that this was not statistically significant (OR?=?1.6). Other risk factors were sleeping in the same house as a case of tuberculosis (OR?=?31.6), living in a house with no piped water (OR?=?7.7) (probably as a proxy for bad living conditions), illiteracy (OR?=?3.7) and male sex (OR?=?1.8). The increase in risk with living in houses with no piped water was much more marked in males. The proportion of cases of tuberculosis attributed to contact with someone with TB was 38% and to illiteracy, lack of piped water and smoking, 20%.

Conclusion

Household contact with tuberculosis, social factors and male sex play the biggest role in determining risk of TB disease among children and adolescents in the study. We recommend further research on the relationship of cigarette smoking on tuberculosis in adolescents, and on whether the sex differentials are more marked in bad living conditions. Separate studies should be conducted in older children and in adolescents.

     

Differential coupling of CC chemokine receptors to multiple heterotrimeric G proteins in human interleukin-2-activated natural killer cells

Using two different approaches, we have investigated the types of G proteins coupled to CC chemokine receptors. First, permeabilization of interleukin-2-activated natural killer (IANK) cells with streptolysin-O and introduction of anti-G protein antibodies inside these cells resulted in the following. (1) Anti-G(s), anti-G(o), and anti-G(z) inhibited the migration of IANK cells in response to macrophage- inflammatory protein-1 alpha (MIP-1 alpha), monocyte chemoattractant protein-1 (MCP-1), or regulated on activation normal T cell expressed and secreted (RANTES). (2) Anti-Gi inhibited their migration in response to MCP-1 or RANTES but not in response to MIP-1 alpha. Second, incubation of IANK cell membranes with anti-G protein antibodies before incubating with (gamma-35S) GTP or (gamma-32P) GTP, resulted in the following. (1) Anti-G(s), anti-G(o), or anti-G(z) inhibited GTP binding and GTPase activity in the presence of MIP-1 alpha, or RANTES. (2) Anti- G(i) inhibited GTP binding and GTPase activity in the presence of MCP-1 or RANTES but not in the presence of MIP-1 alpha. The inhibitory effect of anti-G protein antibodies was reversed upon incubating these antibodies with their respective synthetic peptides before addition to IANK cell membranes. These results suggest that MCP-1 and RANTES receptors are promiscuously coupled to multiple G proteins in IANK cell membranes and that this coupling is different from MIP-1 alpha receptors, which seem to be coupled to G(s), G(o), and G(z) but not to G(i).     

Pre-B acute lymphoblastic leukemia cells may induce T-cell anergy to alloantigen

Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance.     

IgG Against Dengue Virus in Healthy Blood Donors,Zanzibar, Tanzania

We conducted a seroprevalence survey among 500 healthy adult donors at Zanzibar National Blood Transfusion Services. Dengue virus IgG seroprevalence was 50.6% and independently associated with age and urban residence. These data will aid in building a surveillance, preparedness, and response plan for dengue virus infections in the Zanzibar Archipelago.Key words: dengue, seroprevalence, Zanzibar, viruses, vector-borne infections     

The effect of preemptive use of pregabalin on postoperative morphine consumption and analgesia levels after laparoscopic colorectal surgery: a controlled randomized trial

International Journal of Colorectal Disease - In order to reduce postoperative opioid administration and pain levels in patients submitted to laparoscopic colectomy, we assessed the efficacy of...     

An Intensive Intervention to Reduce Readmissions for Frequently Hospitalized Patients: the CHAMP Randomized Controlled Trial

BackgroundA small number of patients are disproportionally readmitted to hospitals. The Complex High Admission Management Program (CHAMP) was established as a multidisciplinary program to improve continuity of care and reduce readmissions for frequently hospitalized patients.ObjectiveTo compare hospital utilization metrics among patients enrolled in CHAMP and usual care.DesignPragmatic randomized controlled trial.ParticipantsInclusion criteria were as follows: 3 or more, 30-day inpatient readmissions in the previous year; or 2 inpatient readmissions plus either a referral or 3 observation admissions in previous 6 months.InterventionsPatients randomized to CHAMP were managed by an interdisciplinary team including social work, physicians, and pharmacists. The CHAMP team used comprehensive care planning and inpatient, outpatient, and community visits to address both medical and social needs. Control patients were randomized to usual care and contacted 18 months after initial identification if still eligible.Main MeasuresPrimary outcome was number of 30-day inpatient readmissions 180 days following enrollment. Secondary outcomes were number of hospital admissions, total hospital days, emergency department visits, and outpatient clinic visits 180 days after enrollment.Key ResultsThere were 75 patients enrolled in CHAMP, 76 in control. Groups were similar in demographic characteristics and baseline readmissions. At 180 days following enrollment, CHAMP patients had more inpatient 30-day readmissions [CHAMP incidence rate 1.3 (95% CI 0.9–1.8) vs. control 0.8 (95% CI 0.5–1.1), p=0.04], though both groups had fewer readmissions compared to 180 days prior to enrollment. We found no differences in secondary outcomes.ConclusionsFrequently hospitalized patients experienced reductions in utilization over time. Though most outcomes showed no difference, CHAMP was associated with higher readmissions compared to a control group, possibly due to consolidation of care at a single hospital. Future research should seek to identify subsets of patients with persistently high utilization for whom tailored interventions may be beneficial.Trial RegistrationClinicalTrials.gov identifier: {"type":"clinical-trial","attrs":{"text":"NCT03097640","term_id":"NCT03097640"}}NCT03097640; https://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT03097640","term_id":"NCT03097640"}}NCT03097640KEY WORDS: care transitions, readmissions, care models, continuity of care, randomized controlled trial

A small number of patients account for a disproportionate number of hospital readmissions.¹ While medically diverse, many patients who are frequently hospitalized have behavioral or social needs that require holistic care models emphasizing more than medical care alone.² This population challenges a system of care that fragments hospital-based care and ambulatory care, creating systematic discontinuity for patients who may require longitudinal relationship-based care to meet their complex needs.³ In qualitative studies, patients who are frequently hospitalized report frustration with care fragmentation, causing them to perceive a lack of continuity and a loss of trust with the medical system.⁴Innovative care models have sought to reduce readmissions through redesigning care delivery, improving care coordination, and connecting patients to existing resources.^5–8 A systematic review of interventions for frequently hospitalized patients found a heterogeneous group of care models.⁹ Importantly, the majority of studies were observational. Many patients experience a reduction in utilization after an initial period of frequent admissions,¹⁰ limiting the ability of observational studies to measure a specific program’s effect due to the natural decline in readmissions over time. A randomized trial of a “healthcare hotspotting” intervention for patients in Camden, NJ, reported no change in hospitalization rates compared to a control group.¹¹ Though this intervention was an intensive interdisciplinary effort that enrolled patients while still hospitalized, it focused primarily on connecting patients to existing outpatient resources. Other intensive outpatient-only interventions have failed to reduce healthcare utilization.¹² Interventions that focus on improving care across clinical settings (i.e., both inside and outside of the hospital) may have a different effect.We created the Complex High Admission Management Program (CHAMP) as a quality improvement initiative to improve inpatient and outpatient care and reduce inpatient readmissions of patients frequently admitted to our hospital. The CHAMP multidisciplinary team works to foster longitudinal relationships with patients who suffer from systematic discontinuity. A pilot pre-post analysis of CHAMP observed reductions in readmission;¹³ however, results may have been confounded by the aforementioned tendency for utilization to decline over time.¹⁰ In this study, we conducted a randomized trial of CHAMP compared with usual care to accurately assess the program’s effect on hospital readmissions.     

Pulp revascularization for immature replanted teeth: a case report

Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization.