The need for systematic quality controls in implementing N95 reprocessing and sterilization

BACKGROUND

Due to increased requirement for personal protective equipment during the coronavirus disease 2019 pandemic, many medical centres utilized sterilization systems approved under Food and Drug Administration Emergency Use Authorization for single-use N95 mask re-use. However, few studies have examined the real-world clinical challenges and the role of ongoing quality control measures in successful implementation.

AIMS

To demonstrate successful implementation of quality control measures in mask reprocessing, and the importance of continued quality assurance.

METHODS

A prospective quality improvement study was conducted at a tertiary care medical centre. In total, 982 3M 1860 masks and Kimberly-Clark Tecnol PFR95 masks worn by healthcare workers underwent sterilization using a vaporized hydrogen peroxide gas plasma-based reprocessing system. Post-processing qualitative fit testing (QFT) was performed on 265 masks. Mannequin testing at the National Institute for Occupational Safety and Health (NIOSH) laboratory was used to evaluate the impact of repeated sterilization on mask filtration efficacy and fit. A locally designed platform evaluated the filtration efficiency of clinically used and reprocessed masks.

FINDINGS

In total, 255 N95 masks underwent QFT. Of these, 240 masks underwent post-processing analysis: 205 were 3M 1860 masks and 35 were PFR95 masks. Twenty-five (12.2%) of the 3M masks and 10 (28.5%) of the PFR95 masks failed post-processing QFT. Characteristics of the failed masks included mask deformation (N=3, all 3M masks), soiled masks (N=3), weakened elastic bands (N=5, three PFR95 masks), and concern about mask shrinkage (N=3, two 3M masks). NIOSH testing demonstrated that while filter efficiency remained >98% after two cycles, mask strap elasticity decreased by 5.6% after reprocessing.

CONCLUSIONS

This study demonstrated successful quality control implementation for N95 mask disinfection, and highlights the importance of real-world clinical testing beyond laboratory conditions.

Pre-ablation interatrial conduction delay or block predicts atrial fibrillation recurrence after ablation among obese patients

Funding Acknowledgements

Type of funding sources: None.

Background

Obesity is associated with greater risk of atrial fibrillation (AF) recurrence post-ablation and higher incidence of conduction delay compared to non-obese patients. Pre-ablation P-wave duration (PWD) and morphology (PWM) indicating interatrial delay are easily assessed in the clinic and may predict AF recurrence post-ablation in these patients.

Purpose

Evaluate the predictive value of PWD and PWM on AF recurrence post-ablation in obese patients.

Methods

Pre-ablation PWD and PWM (negative P-wave in lead II or III) were analyzed on consecutive patients with BMI ≥30 kg/m2 who underwent initial AF ablation from 2012–19. The primary outcome was recurrent AF after a 3-month post-ablation blanking period. Multivariate analysis adjusted for baseline characteristics was performed.

Results

For 205 patients (61.0±9.5 years old, 39.0% female), mean BMI was 36.9±5.7 kg/m2 and 71.7% had persistent AF pre-ablation. Recurrent AF post-ablation occurred in 115 (56.1%) during a median follow up of 491 (270, 1001) days. PWD >130 ms was significantly associated with higher AF recurrence (AHR of 1.62, 95%CI 1.04-2.57, p=0.03) after adjusting for age, persistent AF and left atrial volume index (LAVI). In a subgroup with LAVI <42 mL/m2 (n=112), PWD >130 ms and negative P-waves in lead II or III were independently associated with increased risk of recurrent AF (AHR 2.06, 95%CI 1.12-3.91; p=0.019 and AHR 1.94, 95% CI 1.00-3.56; p=0.05, respectively) (Figure 1).

Conclusion

AF recurred in >50% of obese patients within 1.5 years of ablation. Pre-ablation PWD >130 ms and negative P-waves in lead II or III independently predicted recurrent AF post-ablation in this cohort of obese patients. These easily assessed findings add predictive value to other risk factors.

Differential 18F-NaF uptake in various compartments in knee osteoarthritis: an observational study using PET/MRI

AIM

To investigate if the pattern of fluorine-18-labelled sodium fluoride (¹⁸F-NaF) uptake on integrated positron-emission tomography (PET)/magnetic resonance imaging (MRI) of bone marrow lesions (BML) and osteophytes differs between different knee compartments.

MATERIALS AND METHODS

Sixteen patients with no prior history of knee injury with or without pain were recruited for the study. The images of both knees were acquired on simultaneous PET/MRI. The acquisition was done after 45 minutes of intravenous injection of ¹⁸F-NaF 185-370 MBq (5-10 mCi) for 40 minutes. Each knee was divided into eight compartments patella, trochlea, medial central femur, lateral central femur, medial posterior femur, lateral posterior femur, medial tibia, lateral tibia, and cruciate ligament insertion specifically for BML. BML and osteophytes were scored using MRI Osteoarthritis Knee Score (MOAKS) criteria and their corresponding maximum standardised uptake values (SUVmax) recorded.

RESULTS

BML and osteophytes both showed statistically significant differences among knee compartments, i.e., p-value <0.000 and < 0.043 respectively. SUVmax for BML and osteophytes was greatest in the medial tibia.

CONCLUSION

¹⁸F-NaF PET/MRI showed that BML and osteophytes had differential uptake values due to bone remodelling amongst the various knee compartments and this may help to design disease-modifying osteoarthritis drugs in the future.

Intravenous thrombolysis for large vessel or distal occlusions presenting with mild stroke severity

BACKGROUND AND PURPOSE

We investigated the effectiveness of intravenous thrombolysis (IVT) in acute ischaemic stroke (AIS) patients with large vessel or distal occlusions and mild neurological deficits, defined as National Institutes of Health Stroke Scale scores < 6 points.

METHODS

The primary efficacy outcome was 3-month functional independence (FI) [modified Rankin Scale (mRS) scores 0-2] that was compared between patients with and without IVT treatment. Other efficacy outcomes of interest included 3-month favorable functional outcome (mRS scores 0-1) and mRS score distribution at discharge and at 3 months. The safety outcomes comprised all-cause 3-month mortality, symptomatic intracranial hemorrhage (ICH), asymptomatic ICH and severe systemic bleeding.

RESULTS

We evaluated 336 AIS patients with large vessel or distal occlusions and mild stroke severity (mean age 63 ± 15 years, 45% women). Patients treated with IVT (n = 162) had higher FI (85.6% vs. 74.8%, P = 0.027) with lower mRS scores at hospital discharge (P = 0.034) compared with the remaining patients. No differences were detected in any of the safety outcomes including symptomatic ICH, asymptomatic ICH, severe systemic bleeding and 3-month mortality. IVT was associated with higher likelihood of 3-month FI [odds ratio (OR), 2.19; 95% confidence intervals (CI), 1.09-4.42], 3-month favorable functional outcome (OR, 1.99; 95% CI, 1.10-3.57), functional improvement at discharge [common OR (per 1-point decrease in mRS score), 2.94; 95% CI, 1.67-5.26)] and at 3 months (common OR, 1.72; 95% CI, 1.06-2.86) on multivariable logistic regression models adjusting for potential confounders, including mechanical thrombectomy.

CONCLUSIONS

Intravenous thrombolysis is independently associated with higher odds of improved discharge and 3-month functional outcomes in AIS patients with large vessel or distal occlusions and mild stroke severity. IVT appears not to increase the risk of systemic or symptomatic intracranial bleeding.

72 Prevalence of Reported and Unreported Vertebral Fractures in Ctpas in Older Adults Above 75 Years

Introduction

Identifying vertebral fractures is prudent in the diagnosis of osteoporosis as they occur early in this hidden condition. Unfortunately, due to their unspecific presentation, only 25% are clinically recognised. Computerised Tomography Pulmonary Angiogram (CTPA) are frequently requested to confirm pulmonary thromboembolisms, but could also aid in detecting clinically silent vertebral fractures. Current literature suggests that less than one-third of incidental vertebral fractures are reported. The aim of this study is to measure the prevalence of vertebral fractures in CTPA and its relevance to clinical outcomes.

Methods

This is retrospective observational study based on the analysis of existing CTPA for acutely unwell patients admitted to medical assessment unit or A & E across three acute sites within Aneurin Bevan University Health board, Wales, UK between January and December 2015. All CTPA reports were reviewed for fragility factures and CTPA images were reassessed for any unreported vertebral fractures. Age and gender were recorded for all patients. Analysis was done for all patients in respect to subsequent fragility fractures and mortality. Difference of proportion test was used to compare two groups with and without vertebral fractures.

Results

179 CTPA were reviewed, 161 patients were included for further analysis. 14.3% (n=23/161) were reported to have a vertebral fracture, however only 8.7% (n=14/161) of reports used the correct terminology of ‘fracture’. On subsequent review, an additional 24.2% (n=39/161) vertebral fractures were noted. Therefore, overall prevalence of vertebral fractures was 38.5% (n=62/161). Only 9.1% (n=9/99) of patients without a vertebral fracture developed a subsequent fragility fracture. In comparison, 22.5% (n=14/62) of patients with a previous vertebral fracture sustained a new fragility fracture over next 4 years and this was significantly higher (p = 0.017). Overall mortality over 4 years follow-up was significantly higher for patients with vertebral fractures (64.5%, n=40/62) as compared to those without fractures (43.4%, n=43/99, p = 0.009). Only 48.4% (n=30/62) received osteoporosis treatment.

Conclusions

Vertebral fractures could be underreported by radiologists, likely due to human factors as they might be concentrating on the clinical scenario to exclude a pulmonary embolism. However, considering a significant higher mortality in patients with underlying vertebral fracture, it justifies that radiologists could be asked to examine sagittal view in the bone window for possible underlying vertebral fractures, to ensure osteoporosis is treated to guidance.

Effect of Vitamin D on Canine Distalization and Alveolar Bone Density Using Multi-slice Spiral CT: A Randomized Controlled Trial

AIM

The aim of this split-mouth, blinded randomized controlled trial was to evaluate the clinical and radiographic effects of locally delivered 1,25 dihydroxycholecalciferol (1,25 DHC) on the amount of canine distalization.

MATERIALS AND METHODS

Fifteen patients between age groups of 15 years to 30 years willing to undergo orthodontic treatment in a dental college participated in the study. A computer-generated randomization list was generated to divide the maxillary arch into experimental side and control side. Allocation concealment was applied. Canine distalization was initiated using nickel-titanium (NiTi) closed coil springs delivering a force of 150 g per side, which was attached to the maxillary first molar tube and canine hook. Local periodontal gel injection of 1,25 DHC was given on the experimental side and placebo gel on the control side at distal side of the maxillary canine at monthly interval, respectively. Patients were evaluated from beginning (T₀), 4 weeks (T₁), 8 weeks (T₂), and 12 weeks (T₃). CT scans were taken at T₀ and T₃ to measure the changes in bone density. The difference in amount of canine distalization and the changes in bone density were assessed on the experimental and control sides, respectively. Descriptive statistics and paired t test were used to determine any differences.

RESULTS

The results showed statistically significant increase in the amount of canine distalization and decrease in cancellous bone density on the experimental side when compared to control side.

CONCLUSION

The active form of vitamin D can be an effective agent to accelerate orthodontic tooth movement (OTM).

CLINICAL SIGNIFICANCE

This study provides a new insight into the scope of vitamin D in clinical orthodontics and its innovative method of application to accelerate tooth movement in patients will revolutionize treatment as well as open newer boundaries in orthodontic research at a biomolecular level.

Pediatric Hepatic Venous Outflow Tract Obstruction: Experience from a Transplant Center

We performed a review of case records of children diagnosed with hepatic venous outflow tract obstruction at our center in last 10 years. Out of 11 cases identified, 6 had variable blocks in the hepatic venous system and 4 had combined hepatic venous and inferior vena cava (IVC) block. One child with paroxysmal nocturnal hemoglobinuria (PNH) had isolated IVC involvement. Angioplasty was attempted in 3 patients; among them 2 had successful outcome. Seven children with advanced liver disease underwent transplantation, which was successful in six. With availability of modalities like interventional radiology and transplantation, the overall prognosis of hepatic venous outflow tract obstruction seems to be good when managed in a well-equipped center.

Effects of amine fluoride and probiotic mouthwash on levels of Porphyromonas gingivalis in orthodontic patients: A randomized controlled trial

Introduction

Porphyromonas gingivalis is one among the major etiological agent in periodontal diseases and has been proved to cause gingival inflammation under orthodontic appliances.

Aim

To assess the effect of amine fluoride and probiotic mouthwashes on levels of P. gingivalis during orthodontic treatment, using real time-polymerase chain reaction (RT-PCR).

Materials and Methods

A randomised controlled trial was performed including 45 patients. There were three groups: Group A (control group), Group B (patients using Amflor mouthwash) and Group C (patients using probiotic mouthwash). During the treatment, all the 3 groups were advised to brush twice a day using Colgate tooth paste and Group B patients were advised to swish 15 ml fluoridated mouthwash (Amflor) and Group C advised to swish probiotic for 60 s before swallowing, once in the morning and once before sleep. After gently removing supragingival plaque, subgingival plaque samples were collected by inserting a sterile dental curette into the bottom of the gingival crevice around 31, 32, 41, and 42 at two different intervals: T1 at start and T2 after 6 months of fixed orthodontic treatment. Sub-gingival plaque samples collected were transferred to laboratory within 48 h for RT-PCR analysis in Tris-buffer solution, to maintain the integrity of bacterial DNA.

Results

The levels of P. gingivalis were significantly decreased with probiotic mouth wash.

Conclusions

Probiotic mouth wash can be used as an adjunctive measure along with regular brushing to improve periodontal status during fixed orthodontic treatment.

Genotype-phenotype study in patients with valosin-containing protein mutations associated with multisystem proteinopathy

Mutations in valosin-containing protein (VCP), an ATPase involved in protein degradation and autophagy, cause VCP disease, a progressive autosomal dominant adult onset multisystem proteinopathy. The goal of this study is to examine if phenotypic differences in this disorder could be explained by the specific gene mutations. We therefore studied 231 individuals (118 males and 113 females) from 36 families carrying 15 different VCP mutations. We analyzed the correlation between the different mutations and prevalence, age of onset and severity of myopathy, Paget's disease of bone (PDB), and frontotemporal dementia (FTD), and other comorbidities. Myopathy, PDB and FTD was present in 90%, 42% and 30% of the patients, respectively, beginning at an average age of 43, 41, and 56 years, respectively. Approximately 9% of patients with VCP mutations had an amyotrophic lateral sclerosis (ALS) phenotype, 4% had been diagnosed with Parkinson's disease (PD), and 2% had been diagnosed with Alzheimer's disease (AD). Large interfamilial and intrafamilial variation made establishing correlations difficult. We did not find a correlation between the mutation type and the incidence of any of the clinical features associated with VCP disease, except for the absence of PDB with the R159C mutation in our cohort and R159C having a later age of onset of myopathy compared with other molecular subtypes.

Differential leukocyte counts on admission predict outcomes in patients with acute ischaemic stroke treated with intravenous thrombolysis

BACKGROUND AND PURPOSE

To determine the association of differential leukocyte counts on admission with efficacy and safety outcomes in patients with acute ischaemic stroke (AIS) treated with intravenous thrombolysis (IVT).

METHODS

Consecutive patients with AIS receiving IVT were evaluated at two stroke centers. Differential leukocyte counts and neutrophil:lymphocyte ratio (NLR) were determined during the initial 12 h of admission. Efficacy outcomes were favorable functional outcome (FFO) (modified Rankin Scale scores of 0-1) and functional independence (FI) (modified Rankin Scale scores of 0-2) at 3 months, whereas safety outcomes were symptomatic intracranial hemorrhage and 3-month mortality.

RESULTS

Among 657 IVT-treated patients with AIS, the mean age was 64 ± 14 years, 50% were female and median National Institutes of Health Stroke Scale score was 7 points (interquartile range, 4-13). Lower neutrophil and leukocyte counts and NLR counts were observed in patients with 3-month FFO and FI, whereas higher counts were observed in patients who died at 3 months. The best discriminative factors for 3-month FFO and FI were NLR < 2.2 (sensitivity 51.4%, specificity 63.1%) and leukocyte count <8100/μL (sensitivity 57.5%, specificity 55.1%), respectively. After adjustment for potential confounders, NLR < 2.2 was associated with higher odds of FFO [odds ratio (OR), 1.56; 95% confidence interval (CI), 1.08-2.24; P = 0.018], whereas leukocyte count <8100/μL demonstrated higher odds of 3-month FI (OR, 1.69; 95% CI, 1.11-2.57; P = 0.014) and lower odds of 3-month mortality (OR, 0.31; 95% CI, 0.16-0.60; P = 0.001). Combined neutrophil (<6800/μL) and leukocyte (<8100/μL) counts demonstrated a strong interaction for 3-month FI (OR, 1.73; 95% CI, 1.13-2.67; P interaction = 0.012).

CONCLUSIONS

Differential leukocyte counts on admission were independently associated with clinical outcomes in patients with AIS treated with IVT. These inflammatory biomarkers are potential targets for adjunctive neuroprotection in this stroke subgroup.

Infrapopliteal angioplasty using a combined angiosomal reperfusion strategy

Introduction

Infra-popliteal angioplasty continues to be widely performed with minimal evidence to guide practice. Endovascular device selection is contentious and there is even uncertainty over which artery to treat for optimum reperfusion. Direct reperfusion (DR) targets the artery supplying the ischaemic tissue. Indirect reperfusion (IR) targets an artery supplying collaterals to the ischaemic area. Our unit practice for the last eight years has been to attempt to open all tibial arteries at the time of angioplasty. When successful, this results in both direct and indirect; or combined reperfusion (CR). The aim was to review the outcomes of CR and compare them with DR or IR alone.

Methods

An eight year retrospective review from a single unit of all infra-popliteal angioplasties was undertaken. Wound healing, limb salvage, amputation-free and overall survival data as well as re-intervention rates were captured for all patients. Subgroup analysis for diabetics was undertaken. Kaplan Meier curves are presented for survival outcomes. All odds and hazard ratios (HR) and p values were corrected for bias from confounders using multivariate analysis.

Results

250 procedures were performed: 22 (9%) were CR; 115 (46%) DR and 113 (45%) IR. Amputation-free survival (HR 0.504, p = 0.039) and re-intervention and amputation-free survival (HR 0.414, p = 0.005) were significantly improved in patients undergoing CR compared to IR. Wound healing was similarly affected by reperfusion strategy (OR = 0.35, p = 0.047). Effects of CR over IR were similar when only diabetic patients were considered.

Conclusions

Combined revascularisation can only be achieved in approximately 10% of patients. However, when successful, it results in significant improvements in wound healing and amputation-free survival over simple indirect reperfusion techniques.

Clinical and financial benefits of intra-articular tranexamic acid in total knee arthroplasty

PURPOSE

To determine whether intra-articular tranexamic acid (TXA) use after total knee arthroplasty (TKA) results in decreased postoperative blood transfusion and length of hospital stay.

METHODS

Medical records of 1981 patients (mean age, 69.2 years) who underwent primary TKA with (n=1006) or without (n=975) TXA use by any of 4 knee arthroplasty surgeons were reviewed. TXA (3000 mg/30ml) was administered via an epidural catheter into the knee joint after wound closure. Postoperative blood transfusion was given to patients with haemoglobin (Hb) level <80 g/dl on days 1 and 2 or with symptoms of acute anaemia.

RESULTS

Intra-articular TXA use after TKA resulted in a lower blood transfusion rate (4.5% [45/1006] vs. 14.8% [144/975], p<0.0001), fewer units of blood transfused (86 vs. 313 units, p<0.0001), fewer units of blood transfused per 100 patients (8.5 vs. 32.1, p<0.0001), and shorter length of hospital stay (4.7±2.3 vs. 5.3±2.7 days, p<0.0001). Total cost savings with respect to the reduction in blood transfusion was AU$143.68 per patient. When the change in length of hospital stay and TXA costs were included, the overall saving was AU$631.36 per patient.

CONCLUSION

Intra-articular TXA use can reduce costs as a result of decreased blood transfusion rate and length of hospital stay in patients undergoing TKA.

Ultrastructure of chondrocytes in osteoarthritic femoral articular cartilage

BACKGROUND

Osteoarthritis (OA) is a common problem in elderly, but it is not an inevitable feature of ageing. About 80-90% of individuals of both sexes have radiographic evidence of OA by the time they reach an age of 65. But not all of them have the symptoms like pain and decreased joint motion.

OBJECTIVE

The objective of the present study was conducted to find out whether the osteoarthritic changes in human articular cartilage are similar to the ageing process or not.

METHODS

Femoral articular cartilage specimens obtained from 13 osteoarthritic patients (52-80 years) undergoing total knee replacement and 9 cadavers of same age group (50-80 years) (control) were processed and studied under electron microscope. The ultrastructure of the cartilage from the two groups was compared with each other.

RESULTS

Under the electron microscope, articular cartilage from control group had chondrocytes having a secretary cell characteristic with prominent nucleus and well developed organelles. In osteoarthritic cartilage, degenerating or necrotic chondrocytes were found. Nuclei of these chondrocytes appeared lobulated or indented. Chondrocytes below the fibrillated surface had dilated and irregular endoplasmic reticulum. Electron dense lipid deposits in the extracellular matrix as well as intracytoplasmic glycogen deposits were much increased in osteoarthritic cartilage as compared to the control group. Amount of perinuclear intracytoplasmic fine filaments was also increased in the chondrocytes of osteoarthritic cartilage.

CONCLUSION

Ultrastructural findings of the osteoarthritic articular cartilage were much different from the ageing non-osteoarthritic cartilage. Hence, OA should be considered a specific process and not simply an inevitable feature of ageing.

Mechanisms involved in attenuated cardio-protective role of ischemic preconditioning in metabolic disorders

Myocardial infarction is a pathological state which occurs due to severe abrogation of the blood supply (ischemia) to a part of heart, which can cause myocardial damage. The short intermittent cycles of sub-lethal ischemia and reperfusion has shown to improve the tolerance of the myocardium against subsequent prolonged ischemia/reperfusion (I/R)-induced injury, which is known as ischemic preconditioning (IPC). Although, IPC-induced cardioprotection is well demonstrated in various species, including human beings, accumulated evidence clearly suggests critical abrogation of the beneficial effects of IPC in diabetes mellitus, hyperlipidemia and hyperhomocysteinemia. Various factors are involved in the attenuation of the cardioprotective effect of preconditioning, such as the reduced release of calcitonin gene-related peptide (CGRP), the over-expression of glycogen synthase kinase-3β (GSK-3β) and phosphatase and tensin homolog (PTEN), impairment of mito-KATP channels, the consequent opening of mitochondrial permeability transition pore (MPTP), etc. In this review, we have critically discussed the various signaling pathways involved in abrogated preconditioning in chronic diabetes mellitus, hyperlipidemia and hyperhomocysteinemia. We have also focused on the involvement of PTEN in abrogated preconditioning and the significance of PTEN inhibitors.

Methicillin-resistant Staphylococcus aureus (MRSA)

Staphylococcus aureus is one of the leading causes of surgical site infection (SSI). Over the past decade there has been an increase in methicillin-resistant S. aureus (MRSA). This is a subpopulation of the bacterium with unique resistance and virulence characteristics. Nasal colonisation with either S. aureus or MRSA has been demonstrated to be an important independent risk factor associated with the increasing incidence and severity of SSI after orthopaedic surgery. Furthermore, there is an economic burden related to SSI following orthopaedic surgery, with MRSA-associated SSI leading to longer hospital stays and increased hospital costs. Although there is some controversy about the effectiveness of screening and eradication programmes, the literature suggests that patients should be screened and MRSA-positive patients treated before surgical admission in order to reduce the risk of SSI.

Cite this article: Bone Joint J 2013;95-B:4–9.

Rheological evaluation of thermoreversible and mucoadhesive nasal gels of Zolmitriptan

BACKGROUND AND OBJECTIVES

Rheological evaluation of thermoreversible mucoadhesive nasal gel of zolmitriptan is done to determine the steady shear behaviour and gelation temperature. The thermoreversible mucoadhesive polymers are sucessesfully used to increase the contact time of the therapeutic compound in the nasal cavity as well as they cause enhancement in permeation of drug through the nasal mucosa.

MATERIAL AND METHODS

Pluronic (F127) and Pluronic (F 68) were used as thermoreversible polymers in combination with a mucoadhesive polymer obtained from natural resource Zolmiriptan anti migraine drug obtained from Cipla Ltd. Rheometer Brookfield R/S- CPS- PI having cone-and-plate geometry was used for steady shear behaviour study and the gelation temperature was determined by Brookfield R/S plus Rheometer (Brookfield viscometer Ltd, Harlow, Essex, UK) fitted with spindle and Eurotherm cone/plate geometry.

RESULTS

Steady shear behaviour study concludes as content of mucoadhesive polymer starts increasing subsequently the viscosity of the solution starts increasing in the same manner. Gelation temperature study suggests that as the mucoadhesive content was increased in formulation the gelation temperature of the formulation was decreased subsequently. So it was concluded from the study that gelation temperature of the formulation was influenced by the mucoadhesive content. Temperature increases the gelation time of the formulation.

CONCLUSIONS

Above studies indicate that even small difference in the composition of the thermoreversible mucoadhesives gel formulations may cause major change in the rheological behaviour. Although the gelation temperatures of all the three formulations L1, L2 and L3 were below the human nasal temperature, they show different responses to the varied shear rates at different temperatures below and above the temperature of nasal cavity.

Biochemical characterization of dipeptidylcarboxypeptidase of Leishmania donovani

The incidence of parasitic infection, leishmaniasis, has been steadily increasing worldwide. Since, the existing chemotherapy of these diseases suffers from lack of safe and effective drugs and/or the presence of widespread drug resistance, there is an urgent need for development of potent, mechanism-based anti-parasitic agents. The peptidases of protozoan parasites are becoming increasingly important for their role in parasite survival and pathogenecity. Leishmania donovani dipeptidylcarboxypeptidsae (LdDCP), an angiotensin converting enzyme (ACE) related metallopeptidase has been identified and characterized as a putative drug target for antileishmanial chemotherapy. The kinetic parameters for LdDCP with substrate, Hip-His-Leu were determined as, Km, 4 mM and Vmax, 1.173 μmole/ml/min. The enzyme was more sensitive to 1,10 phenanthroline than EDTA and was 80% inhibited in presence of NaCl. Among various protease inhibitors, pepstatin was found as potent inhibitor of LdDCP.

Muckle-Wells syndrome/neonatal-onset multisystem inflammatory disease overlap associated with myelodysplasia and cerebrovascular accident

We describe a patient with overlapping clinical features of Muckle-Wells syndrome and neonatal-onset multisystem inflammatory disease with an absence of mutation in exon 3 of the CIAS1 ⁄ PYPAF1 ⁄ NALP3 gene. Myelodysplasia and cerebrovascular accident were additional features in this patient, which to our knowledge have not been previously described in association with these disorders. The urticarial rash, myelodysplasia and raised inflammatory markers responded to treatment with the interleukin-1 receptor antagonist, anakinra.

Plasminogen activator inhibitor-1 and vitronectin expression level and stoichiometry regulate vascular smooth muscle cell migration through physiological collagen matrices

BACKGROUND

Vascular smooth muscle cell (VSMC) migration is a critical process in arterial remodeling. Purified plasminogen activator inhibitor-1 (PAI-1) is reported to both promote and inhibit VSMC migration on two-dimensional (D) surfaces.

OBJECTIVE

To determine the effects of PAI-1 and vitronectin (VN) expressed by VSMC themselves on migration through physiological collagen matrices.

METHODS

We studied migration of wild-type (WT), PAI-1-deficient, VN-deficient, PAI-1/VN doubly-deficient (DKO) and PAI-1-transgenic (Tg) VSMC through three-D collagen gels.

RESULTS

WT VSMC migrated significantly slower than PAI-1- and VN-deficient VSMC, but significantly faster than DKO VSMC. Experiments with recombinant PAI-1 suggested that basal VSMC PAI-1 expression inhibits migration by binding VN, which is secreted by VSMC and binds collagen. However, PAI-1-over-expressing Tg VSMC migrated faster than WT VSMC. Reconstitution experiments with recombinant PAI-1 mutants suggested that the pro-migratory effect of PAI-1 over-expression required its anti-plasminogen activator (PA) and LDL receptor-related protein (LRP) binding functions, but not VN binding. While promoting VSMC migration in the absence of PAI-1, VN inhibited the pro-migratory effect of active PAI-1.

CONCLUSIONS

In isolation, VN and PAI-1 are each pro-migratory. However, via formation of a high-affinity, non-motogenic complex, PAI-1 and VN each buffers the other's pro-migratory effect. The level of PAI-1 expression by VSMC and the concentration of VN in extracellular matrix are critical determinants of whether PAI-1 and VN promote or inhibit migration. These findings help to rectify previously conflicting reports and suggest that PAI-1/VN stoichiometry plays an important role in VSMC migration and vascular remodeling.

Non-invasive evaluation of liver cirrhosis using ultrasound

Ultrasound (US) is essential in both assessment of the potentially cirrhotic liver and surveillance of selected patients with chronic hepatitis as liver biopsy can be misleading or inaccurate in up to 25% of cases. Various techniques are already in routine use, such as grey-scale imaging, Doppler US, and contrast-enhanced US (CEUS), while newer techniques such as elastography and hepatic vein transit time (HVTT) have the potential to exclude patients without significant fibrosis or cirrhosis; however, they are operator dependent and require specific software. Grey-scale imaging may demonstrate changes, such as volume redistribution, capsule nodularity, parenchymal nodularity, and echotexture changes. The Doppler findings in the hepatic and portal veins, hepatic artery, and varices allow assessment of liver cirrhosis. However, the operator needs to be aware of limitations of these techniques. Low mechanical index CEUS plays an important role in the assessment of complications of cirrhosis, such as hepatocellular carcinoma and portal vein thrombus. Optimized US technique is crucial for accurate diagnosis of the cirrhotic liver and its complications.