Impact of elexacaftor/tezacaftor/ivacaftor on respiratory colonization in an adult cystic fibrosis clinic

BACKGROUND

Little research has been completed on the correlation between cystic fibrosis (CF) modulator therapy and its effect on respiratory cultures in CF patients. This study evaluated the effect of elexacaftor/tezacaftor/ivacaftor (ETI) on respiratory colonization with Pseudomonas aeruginosa.

METHODS

This single center, IRB approved, retrospective chart review compared patient data two years immediately prior to ETI initiation with patient data two years post-initiation from January 2017-December 2022. Patients were included in the study if they were at least 18 years old with a diagnosis of CF and had at least one month of ETI dispensed, at least one sputum culture obtained, and were currently on ETI. Those who had not been seen since ETI initiation or received a bilateral lung transplant were excluded. The primary outcome was rate of patients with respiratory colonization post-ETI. Colonization was defined as two or more positive P. aeruginosa cultures in a 12-month period. Decolonization was defined as three consecutive negative P. aeruginosa cultures after previous colonization. Key secondary outcomes included average time to discontinuation of mucolytic therapy and relative risk of pulmonary exacerbation.

RESULTS

A significant reduction (p<0.001) in colonization with P. aeruginosa was observed with 49 patients in the pre-ETI group compared to 25 in the post-ETI group meeting the definition of colonization (n=79). Average time to discontinuation of mucolytic therapy was 14 months (p=0.002). Relative risk of pulmonary exacerbation was 4.80 (p<0.001).

CONCLUSIONS

ETI use resulted in reduced colonization with P. aeruginosa, discontinuation of mucolytic therapy, and decreased frequency of pulmonary exacerbation.

Combinational antimicrobial activity of biogenic TiO2 NP/ZnO NPs nanoantibiotics and amoxicillin-clavulanic acid against MDR-pathogens

The development of effective strategies against multidrug-resistant (MDR) pathogens is an urgent need in modern medicine. Nanoantibiotics (nABs) offer a new hope in countering the surge of MDR-pathogens. The aim of the current study was to evaluate the antibacterial activity of two attractive nABs, TiO2 NPs and ZnO NPs, and their performance in improving the antimicrobial activity of defined antibiotics (amoxicillin-clavulanic acid, amox-clav) against MDR-pathogens. The nABs were synthesized using a green method. The physicochemical characteristics of the synthesized nanoparticles were determined using standard methods. The results showed the formation of pure anatase TiO2 NPs and hexagonal ZnO NPs with an average particle size of 38.65 nm and 57.87 nm, respectively. The values of zeta potential indicated the high stability of the samples. At 8 mg/mL, both nABs exhibited 100 % antioxidant activity, while ZnO showed significantly higher activity at lower concentrations. The antibiofilm assay showed that both nABs could inhibit the formation of biofilms of Acinetobacter baumannii 80 and Escherichia coli 27G (MDR-isolates). However, ZnO NPs showed superior antibiofilm activity (100 %) against E. coli 27G. The MIC values were determined to be 8 (1), 2 (2), and 4 (4) mg/mL for amox-clav, TiO2 NPs, and ZnO NPs against A. baumannii 80 (E. coli 27G), respectively. The results showed that both nABs had synergistically enhanced antibacterial performance in combination with amox-clav. Specifically, an 8-fold reduction in MIC values of antibiotics was observed when they were combined with nABs. These findings highlight the potential of TiO2 NPs and ZnO NPs as effective nanoantibiotics against MDR-pathogens. The synergistic effect observed when combining nABs with antibiotics suggests a promising approach for combating antibiotic resistance. Further research and development in this area could lead to the development of more effective treatment strategies against MDR infections.

Ceragenin-mediated disruption of Pseudomonas aeruginosa biofilms

BACKGROUND

Microbial biofilms, as a hallmark of cystic fibrosis (CF) lung disease and other chronic infections, remain a desirable target for antimicrobial therapy. These biopolymer-based viscoelastic structures protect pathogenic organisms from immune responses and antibiotics. Consequently, treatments directed at disrupting biofilms represent a promising strategy for combating biofilm-associated infections. In CF patients, the viscoelasticity of biofilms is determined mainly by their polymicrobial nature and species-specific traits, such as Pseudomonas aeruginosa filamentous (Pf) bacteriophages. Therefore, we examined the impact of microbicidal ceragenins (CSAs) supported by mucolytic agents-DNase I and poly-aspartic acid (pASP), on the viability and viscoelasticity of mono- and bispecies biofilms formed by Pf-positive and Pf-negative P. aeruginosa strains co-cultured with Staphylococcus aureus or Candida albicans.

METHODS

The in vitro antimicrobial activity of ceragenins against P. aeruginosa in mono- and dual-species cultures was assessed by determining minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC). Inhibition of P. aeruginosa mono- and dual-species biofilms formation by ceragenins alone and in combination with DNase I or poly-aspartic acid (pASP) was estimated by the crystal violet assay. Additionally, the viability of the biofilms was measured by colony-forming unit (CFU) counting. Finally, the biofilms' viscoelastic properties characterized by shear storage (G') and loss moduli (G"), were analyzed with a rotational rheometer.

RESULTS

Our results demonstrated that ceragenin CSA-13 inhibits biofilm formation and increases its fluidity regardless of the Pf-profile and species composition; however, the Pf-positive biofilms are characterized by elevated viscosity and elasticity parameters.

CONCLUSION

Due to its microbicidal and viscoelasticity-modifying properties, CSA-13 displays therapeutic potential in biofilm-associated infections, especially when combined with mucolytic agents.

Investigation of the principle of concoction by using the processing excipient Glycyrrhiza uralensis Fisch. juice to reduce the main toxicity of Dioscorea bulbifera L. and enhance its main efficacy as expectorant and cough suppressant

ETHNOPHARMACOLOGICAL RELEVANCE

Dioscorea bulbifera L. (Rhizoma Dioscoreae Bulbiferae; RDB) is commonly used as an expectorant and cough suppressant herb but is accompanied by severe hepatotoxicity. Using the juice of auxiliary herbs (such as Glycyrrhiza uralensis Fisch. (Glycyrrhizae Radix et Rhizoma; GRR) juice) in concocting poisonous Chinese medicine is a conventional method to reduce toxicity or increase effects. Our previous study found that concoction with GRR juice provided a detoxifying effect against the major toxic hepatotoxicity induced by RDB, but the principle for the detoxification of the concoction is unknown to date.

AIM OF THE STUDY

The principle of concoction was investigated by using the processing excipient GRR juice to reduce the major toxic hepatotoxicity of RDB, and the efficacy of RDB as an expectorant and cough suppressant was enhanced.

MATERIALS AND METHODS

In this study, common factors (RDB:GRR ratio, concocted temperature, and concocted time) in the concoction process were used for the preparation of each RDB concocted with GRR juice by using an orthogonal experimental design. We measured the content of the main toxic compound diosbulbin B (DB) and serum biochemical indicators and performed pathological analysis in liver tissues of mice to determine the best detoxification process of RDB concocted with GRR juice. On this basis, the biological mechanisms of target organs were detected by Western blot and enzyme-linked immunosorbent assay at the inflammation and apoptosis levels. Further, the effects of RDB on expectorant and cough suppressant with GRR juice were evaluated by the conventional tests of phenol red expectorant and concentrated ammonia-induced cough. Lastly, the major compounds in the GRR juice introduced to RDB concoction were determined.

RESULTS

RDB concocted with GRR juice significantly alleviated DB content, serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase levels, and improved liver pathological damages. The best detoxification process was achieved by using an RDB:GRR ratio of 100:20 at 120 °C for 20 min. Further, RDB concocted with GRR juice down-regulated the protein levels of nuclear factor kappa B (NF-κB), cyclooxygenase 2 (COX-2), and Bcl-2 related X protein (Bax) in the liver and enhanced the expectorant and cough suppressant effects of RDB. Finally, liquiritin (LQ) and glycyrrhizic acid (GA) in the GRR juice were introduced to the RDB concoction.

CONCLUSION

Concoction with GRR juice not only effectively reduced the major toxic hepatotoxicity of RDB but also enhanced its main efficacy as an expectorant and cough suppressant, and that the rationale for the detoxification and/or potentiation of RDB was related to the reduction in the content of the main hepatotoxic compound, DB, the introduction of the hepatoprotective active compounds, LQ and GA, in the auxiliary GRR juice, as well as the inhibition of NF-κB/COX-2/Bax signaling-mediated inflammation and apoptosis.

Administration of maximum dose of mucolytic solution before upper endoscopy - a double-blind, randomized trial

OBJECTIVE

The aim of the study was to demonstrate that an administration of mucolytic solution with a maximum dose of simethicone and n -acetylcysteine before upper endoscopy improves mucosal visibility compared to a group without administration of mucolytic solution or water.

METHODS

This study was a double-blind, randomized controlled trial. Patients were randomized into four groups, with the administration of 100 ml of water + 600 mg n -acetylcysteine + 400 mg simethicone, 100 ml of water + 400 mg n -acetylcysteine + 20 mg simethicone, 100 ml of water, and without any water or mucolytic solution. During the examination, a total of 10 images were taken in the defined areas. The overall visibility score was given by the sum of the 0-5 scores of the five areas and was assessed by the endoscopist performing the procedure and the blinded endoscopists using static images.

RESULTS

A total of 129 patients were randomized. The group of patients did not differ in age, sex distribution, and indications significantly. The overall visibility score as assessed by the endoscopist performing the procedure was significantly higher in the group with the maximum dose of mucolytic solution compared to the group without solution or water (18.9 ± 2.9 vs. 16.6 ± 3.3, P  = 0.023). This difference was not evident by the blinded evaluation of static photographs.

CONCLUSION

Administration of mucolytic solution with a maximum dose of n -acetylcysteine and simethicone before upper endoscopy improved mucosal visibility in the upper gastrointestinal tract compared with the group without any preparation while evaluated by performing endoscopist.

Degradation kinetics and formation of regulated and emerging disinfection by-products during chlorination of two expectorants ambroxol and bromhexine

Ambroxol hydrochloride (AMB) and bromhexine hydrochloride (BRO) are classic expectorants and bronchosecretolytic pharmaceuticals. In 2022, both AMB and BRO were recommended by medical emergency department of China to alleviate cough and expectoration for symptoms caused by COVID-19. The reaction characteristics and mechanism of AMB/BRO with chlorine disinfectant in the disinfection process were investigated in this study. The reaction of chlorine with AMB/BRO were well described by a second-order kinetics model, first-order in both AMB/BRO and chlorine. The second order rate reaction constant of AMB and BRO with chlorine at pH 7.0 were 1.15 × 10² M^-1s^-1 and 2.03 × 10² M^-1s^-1, respectively. During chlorination, a new class of aromatic nitrogenous disinfection by-products (DBPs) including 2-chloro-4, 6-dibromoaniline and 2, 4, 6-tribromoaniline were identified as the intermediate aromatic DBPs by gas chromatography-mass spectrometry. The effect of chlorine dosage, pH, and contact time on the formation of 2-chloro-4, 6-dibromoaniline and 2, 4, 6-tribromoaniline were evaluated. In addition, it was found that bromine in AMB/BRO were vital bromine source to greatly promote the formation of classic brominated DBPs, with the highest Br-THMs yields of 23.8% and 37.8%, respectively. This study inspired that bromine in brominated organic compounds may be an important bromine source of brominated DBPs.

Metagenomic next-generation sequencing as an unconventional approach to warn of tumor cells in a patients with non-mucinous pneumonic-type lung adenocarcinoma: Case report

RATIONALE

Pneumonic-type lung cancer (PTLC) is a special type of lung cancer with cough and expectoration as the main clinical symptoms and inflammatory signals as the main imaging manifestations. PTLC can be easily misdiagnosed as pneumonia, and the diagnosis and treatment are always delayed. Metagenomic next-generation sequencing (mNGS), as an emerging and effective method to identify occult pathogens, has been gradually adopted by clinicians.

PATIENT CONCERNS

A 58-year-old woman with recurrent cough and expectoration was admitted to hospital on January 12th, 2022. She reported that she was diagnosed with pneumonia half a month ago, after treatment with expectorant and antibiotics for 5 days, the symptoms were relieved. However, the symptoms worsened again 10 days after stopping the drugs. On the current presentation, she denied exposure to patients with infection of COVID-19, smoking history, night sweats, weight loss, rash, joint pain, fever, and shortness of breath.

DIAGNOSES

The patient was diagnosed with non-mucinous pneumonic-type lung adenocarcinoma according to the clinical symptoms, changes of CT scans after treatment and cytopathology examinations.

INTERVENTIONS AND OUTCOMES

The patient was initially diagnosed with pulmonary infection according to computerized tomography (CT) scan. Expectorant and antibiotics used. However, the symptoms worsened again 10 days after stopping the drugs. On her return visit, the CT scan did not showed obvious consolidation absorption and was similar to the previous imaging findings. mNGS was performed to detect the occult pathogens. None pathogen was detected, however, 39 copy number variations were found in Human Chromosomal Instability Analysis of mNGS indicating the presence of tumor cells. The cytopathology findings confirmed the presence of lung adenocarcinoma (non-mucinous adenocarcinoma). She was treated with targeted antitumor drugs, and the CT scan after 20 days of targeted antitumor therapy showed obvious absorption of the lesions.

LESSONS

mNGS may have potential value to screen tumor cells in bronchoalveolar lavage fluid of patients with PTLC, especially in the patients whose samples in bronchioli cannot be collected using existing sampling tools.

A Review of the Phytochemistry and Pharmacology of the Fruit of Siraitia grosvenorii (Swingle): A Traditional Chinese Medicinal Food

Siraitia grosvenorii (Swingle) C. Jeffrey ex Lu et Z. Y. Zhang is a unique economic and medicinal plant of Cucurbitaceae in Southern China. For hundreds of years, Chinese people have used the fruit of S. grosvenorii as an excellent natural sweetener and traditional medicine for lung congestion, sore throat, and constipation. It is one of the first species in China to be classified as a medicinal food homology, which has received considerable attention as a natural product with high development potential. Various natural products, such as triterpenoids, flavonoids, amino acids, and lignans, have been released from this plant by previous phytochemical studies. Phar- macological research of the fruits of S. grosvenorii has attracted extensive attention, and an increasing number of extracts and compounds have been demonstrated to have antitussive, expectorant, antiasthmatic, antioxidant, hypoglycemic, immunologic, hepatoprotective, antibacte- rial, and other activities. In this review, based on a large number of previous studies, we summarized the related research progress of the chemical components and pharmacological effects of S. grosvenorii, which provides theoretical support for further investigation of its biological functions and potential clinical applications.

Deep Learning Combined with Hyperspectral Imaging Technology for Variety Discrimination of Fritillaria thunbergii

Traditional Chinese herbal medicine (TCHM) plays an essential role in the international pharmaceutical industry due to its rich resources and unique curative properties. The flowers, stems, and leaves of Fritillaria contain a wide range of phytochemical compounds, including flavonoids, essential oils, saponins, and alkaloids, which may be useful for medicinal purposes. Fritillaria thunbergii Miq. Bulbs are commonly used in traditional Chinese medicine as expectorants and antitussives. In this paper, a feasibility study is presented that examines the use of hyperspectral imaging integrated with convolutional neural networks (CNN) to distinguish twelve (12) Fritillaria varieties (n = 360). The performance of support vector machines (SVM) and partial least squares-discriminant analysis (PLS-DA) was compared with that of convolutional neural network (CNN). Principal component analysis (PCA) was used to assess the presence of cluster trends in the spectral data. To optimize the performance of the models, cross-validation was used. Among all the discriminant models, CNN was the most accurate with 98.88%, 88.89% in training and test sets, followed by PLS-DA and SVM with 92.59%, 81.94% and 99.65%, 79.17%, respectively. The results obtained in the present study revealed that application of HSI in conjunction with the deep learning technique can be used for classification of Fritillaria thunbergii varieties rapidly and non-destructively.

Interventions for the treatment of persistent post-COVID-19 olfactory dysfunction

BACKGROUND

Olfactory dysfunction is a common consequence of COVID-19 infection and persistent symptoms can have a profound impact on quality of life. At present there is little guidance on how best to treat this condition. A variety of interventions have been suggested to promote recovery, including medication and olfactory training. However, it is uncertain whether any intervention is of benefit. This is an update of the 2021 review with one additional study added.  OBJECTIVES: 1) To evaluate the benefits and harms of any intervention versus no treatment for people with persisting olfactory dysfunction due to COVID-19 infection.  2) To keep the evidence up-to-date, using a living systematic review approach.  SEARCH METHODS: The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the latest search was 20 October 2021.   SELECTION CRITERIA: We included randomised controlled trials (RCTs) in people with COVID-19 related olfactory disturbance that had persisted for at least four weeks. We included any intervention compared to no treatment or placebo.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were the recovery of sense of smell, disease-related quality of life and serious adverse effects. Secondary outcomes were the change in sense of smell, general quality of life, prevalence of parosmia and other adverse effects (including nosebleeds/bloody discharge). We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included two studies with 30 participants. The studies evaluated the following interventions: systemic corticosteroids plus intranasal corticosteroid/mucolytic/decongestant and palmitoylethanolamide plus luteolin.  Systemic corticosteroids plus intranasal corticosteroid/mucolytic/decongestant compared to no intervention We included a single RCT with 18 participants who had anosmia for at least 30 days following COVID-19 infection. Participants received a 15-day course of oral corticosteroids combined with nasal irrigation (consisting of an intranasal corticosteroid/mucolytic/decongestant solution) or no intervention. Psychophysical testing was used to assess olfactory function at 40 days. This is a single, small study and for all outcomes the certainty of evidence was very low. We are unable to draw meaningful conclusions from the numerical results. Palmitoylethanolamide plus luteolin compared to no intervention We included a single RCT with 12 participants who had anosmia or hyposmia for at least 90 days following COVID-19 infection. Participants received a 30-day course of palmitoylethanolamide and luteolin or no intervention. Psychophysical testing was used to assess olfactory function at 30 days. This is a single, small study and for all outcomes the certainty of evidence was very low. We are unable to draw meaningful conclusions from the numerical results.

AUTHORS' CONCLUSIONS

There is very limited evidence available on the efficacy and harms of treatments for persistent olfactory dysfunction following COVID-19 infection. However, we have identified a number of ongoing trials in this area. As this is a living systematic review we will update the data regularly, as new results become available.

[Features of topical therapy of inflammatory pathology of nasal cavity]

Treatment of inflammatory pathology of the nasal cavity at the present stage requires a doctor to clearly understand the physiological mechanisms that implement the main functions of the mucous membrane of the nasal cavity and upper respiratory tract. One of the most important processes that ensure the normal functioning of the respiratory tract is mucociliary clearance. Violations of its work leads to stagnation of mucus and the development of inflammation not only in the nasal cavity, but also in the lower respiratory tract and middle ear cavities. The authors of the article consider the main etiological factors and mechanisms of the pathogenesis of inflammatory diseases of the nasal cavity, discuss approaches to the treatment of these conditions. The authors conclude that in conditions of acute and chronic inflammation of the nasal mucosa, accompanied by the secretion of thick viscous mucus, the most effective topical use of the combined preparation, which includes acetylcysteine, tuaminoheptane and sodium hyaluronate. This combination has both mucolytic, vasoconstrictive and protective effects, which increases the effectiveness of the drug and the adherence of patients to therapy.

The Use of Mucolytic Agent in Percutaneous Drainage of Liver Abscess: A Case-Series Analysis

Background: Liver abscess is a scarce but potentially fatal suppurative process. There is a general tendency for minimally invasive treatment, such as broad-spectrum antibiotherapy and percutaneous drainage. Multiloculated, multiple or incompletely liquefied abscesses often limit the efficacy of percutaneous drainage. This study aims to assess the effectiveness of percutaneous drainage and intracavitary instillation of a mucolytic agent for liver abscesses. Material and method: From our department database, we have identified patients with liver abscess admitted during the period 2015 - 2020, treated by ultrasound-guided percutaneous drainage and intracavitary instillation of mucolytic agent. Data regarding imaging appearance, drainage technique, inflammatory markers and clinical course were assessed. Results: Twenty-one patients with multiloculated liver abscesses, sized 8 to 17 cm, were percutaneously drained, with local anaesthesia, under ultrasound guidance. The bacteriological exam of the aspirate showed bacterial infection in 19 cases, mostly Klebsiella pneumoniae, and 2 fungal infections. Acetylcysteine in dilution 1: 1 with saline was instilled daily on the 12F or 14 F drainage catheter. Clinical and radiological resolution was achieved within 14 to 29 days. Two cases required supplementary drainage of a non-communicating residual cavity. There were no complications, periprocedural deaths or relapse at 3 months follow-up. Conclusions: Percutaneous drainage is effective even in the management of multiloculated liver abscesses, facilitated by the use of intracavitary mucolytic agent.

Optimization of pathogenetic therapy in patients with chronic obstructive lung disease

OBJECTIVE

The aim of the study is to increase the effectiveness of the treatment of exacerbation of COPD group B GOLD II with the use of combined therapy of the combined drug PulmoBRIZ containing two components - ambroxol and acetylcysteine and the course of halotherapy.

PATIENTS AND METHODS

Materials and methods: We observed 60 patients with COPD B, GOLD II. They were divided into two groups: the first - the main (n=30) - patients receiving basic therapy, mucolytic therapy - a combination of Ambroxol and acetylcysteine - 200/30 to 1 tabl. 2 times a day, number 7 days and, from the 3rd day - sessions of halotherapy 1 time per day № 10. The second group, the control group (n=30), followed only basic therapy, did not take mucolytics and halotherapy sessions.

RESULTS

Results: Patients receiving therapy with the combination of ambroxol and acetylcysteine and halotherapy sessions experienced a significant increase in FEV1 by 8.3% (p <0.05); the Tiffon index was 7.2% (p<0.05), reactive anxiety levels (RA) and manifestations of autonomic dysfunction decreased, whereas in patients in the control group these indicators did not improve significantly.

CONCLUSION

Conclusions: The proposed complex therapy of COPD patients with the inclusion of the combined drug ambroxol and acetylcysteine and halotherapy sessions contributes to the improvement of the quality of life of patients.

Cysteamine Enhances Biofilm Eradication Efficacy of Calcium Hydroxide

INTRODUCTION

Calcium hydroxide (Ca[OH]2) is a widely used interappointment dressing, but its antibacterial property is compromised by dentin. Hence, the addition of chlorhexidine (CHX) with Ca(OH)2 has been proposed. However, the antimicrobial efficacy of this mixture compared with Ca(OH)2 alone is currently still debatable. Cysteamine is a mucolytic agent used to reduce the viscosity of mucus through the disruption of proteins, which are also important components of the extracellular matrix of biofilms. The aims of this study were to determine the efficacy of cysteamine alone and in combination with Ca(OH)2 to eradicate Enterococcus faecalis biofilm compared with CHX with Ca(OH)2, and to determine if this effect is affected by dentin.

METHODS

The biofilm eradication efficacies of Ca(OH)2 alone and with cysteamine were determined using 7-day E. faecalis biofilm cultured on dentin discs and compared with Ca(OH)2 with 2% CHX. The effects of dentin on the efficacies of Ca(OH)2 alone and with either cysteamine or CHX were examined.

RESULTS

Cysteamine alone completely abolished E. faecalis biofilm at 200 mg/mL. The combination of Ca(OH)2 with either cysteamine at 10 mg/mL or 2% CHX completely obliterated E. faecalis biofilm. Cysteamine with Ca(OH)2 completely eradicated E. faecalis biofilm despite preincubation with dentin, whereas CHX with Ca(OH)2 was less effective.

CONCLUSIONS

Cysteamine effectively eliminated E. faecalis biofilm and showed synergistic effects in combination with Ca(OH)2, which were unaffected by dentin. Hence, our findings support the use of cysteamine as a potential adjunct to Ca(OH)2 as an interappointment dressing.

[Mucolytic and antioxidant agents for exacerbations of chronic obstructive pulmonary disease: A meta-analysis]

OBJECTIVE

To assess the effects and safety of long-term oral mucolytic and antioxidant agents for exacerbations in patients with stable chronic obstructive pulmonary disease. And to further discuss the drug dose and concomitant ICS on the effects.

METHODS

Systematic searches were performed in Medline and Google Scholar databases. Randomized controlled trials which compared regular oral mucolytic and antioxidant agents with placebo and reported exacerbations over a treatment period more than 3 months were selected. Stata version 11 was used for data analysis.

RESULTS

Ten RCTs involving 3 434 patients were identified. Compared with placebo, the use of mucolytic and antioxidant agents was associated with a reduction of 0.36 exacerbations per patient per year (95%CI 0.47 to 0.26). The subgroup analysis restricting to studies without concomitant ICS indicated that there was a larger decrease between the two groups (WMD=-0.58, 95% CI -0.89--0.27). The analysis of NAC dose on the effect indicated that high-dose NAC treatment could significantly reduce the exacerbations (WMD=-0.39, 95% CI -0.61--0.16, z=3.33, P=0.001). While in the low-dose NAC group, only those studies with low rate of concomitant ICS showed the effects (WMD=-1.25, 95% CI -1.99--0.51, z=3.32, P=0.001), the difference was not significant in studies with high rate of concomitant ICS (WMD=-0.06, 95% CI -0.29--0.17, z=0.5, P=0.617). There was no difference in FEV1 improvement (SMD=0.03, 95%CI -0.09～0.15, z=0.49, P=0.626), but FEF 25%-75% showed a significant improvement (SMD=0.41, 95% CI 0.13-0.68, z=2.90, P=0.004).

CONCLUSION

The use of mucolytic and antioxidant agents is associated with a reduction in the number of exacerbations. The effects may be larger in those patients without concomitant ICS. High-dose NAC treatment may be more effective than low-dose group, while the latter may be effective only when the rate of concomitant ICS was low.

The expectorant action of cephaeline, emetine and 2-dehydroemetine

Cephaeline, emetine and 2-dehydroemetine were administered, as the dihydrochlorides, in doses from 0.1 to 81 mg/kg body weight, orally and subcutaneously to 135 rabbits and 92 cats arranged for the collection of respiratory tract fluid. To the extent that comparisons were made, the effects of the three alkaloids were identical. The volume output of respiratory tract fluid was increasingly augmented by doses of from 0.1 to 1.0 mg/kg. No further increase followed administration of higher doses up to the highest non-lethal dose. Doses of from 9.0 to 81 mg/kg were increasingly lethal and increasingly depressed the output of respiratory tract fluid, probably through their cardiotoxic action. Lethal doses were similar for all three alkaloids and by both routes of administration. It is concluded that the expectorant action of ipecacuanha is due in whole or in major part to its content of emetine and cephaeline. The expectorant action of synthetic 2-dehydroemetine is essentially similar to that of emetine and cephaeline.

Iodine-induced hypothyroidism and its effect on the severity of asthma

Among 1107 patients with asthma or chronic asthmatic bronchitis and 96 with hypothyroidism we found 12 patients with both diseases. Seven of these patients had hypothyroidism induced by iodine-containing expectorants. Five of 209 patients with hyperthyroidism had coexistent asthmatic lung disease, but none of these five had been taking iodine. The severity of asthma is considered in relation to changes in thyroid function following withdrawal of iodine. Three patients had an exacerbation of their asthma, while another three had no change in their asthma when the iodine treatment was discontinued and the euthyroid state subsequently restored. All six patients had a marked improvement of their general wellbeing when the euthyroid state was re-established. It is concluded that treatment with iodine-containing expectorants causing hypothyroidism is unwise and should be withdrawn even when the patients praise the beneficial effect of iodine on the asthma per se.

Premedication with pronase or N-acetylcysteine improves visibility during gastroendoscopy: An endoscopist-blinded, prospective, randomized study

AIM: To assess the efficacy of premedicaton with pronase or N-acetylcysteine (NAC) at 20 min before upper gastrointestinal (UGI) endoscopy and to determine whether pronase or NAC pretreatment influences the reliability of the rapid urease test.

METHODS: A total of 146 patients were prospectively and randomly assigned into the study groups according to different premedications before endoscopy. One endoscopist assessed mucosal visibility (MV) with scores ranged from 1 to 4 at four sites in the stomach. The sum of the MV scores from these four locations was defined as the total mucosal visibility (TMV) score. Identification of H pylori was performed using CLO test, histology, and serology.

RESULTS: The Group with pronase premedication had a significantly lower TMV score than did the groups with gascon and gascon water (p < 0.001 and p < 0.01, respectively). The group with NAC had a significantly lower TMV score than the group with gascon (p < 0.01) and a trend of a lower MV score than the group with gascon water (p = 0.06). The TMV score did not significantly differ between the group with pronase and the group with NAC (p = 0.39 and p = 0.14, respectively). The sensitivity and specificity of the CLO test were 92.5% and 93.9%, respectively, in groups premedicated with pronase and NAC together.

CONCLUSION: Premedication with pronase or NAC at 20 min before UGI endoscopy improves the mucosal visibility of the stomach. Neither pronase nor NAC produces any obvious interference with the CLO test for the identification of H pylori infection.

Prevention of biofilm formation by dairy products and N-acetylcysteine on voice prostheses in an artificial throat

OBJECTIVE

To evaluate the preventive effect of buttermilk, Yakult Light fermented milk drink and N-acetylcysteine on biofilm formation on voice prostheses in vitro.

MATERIAL AND METHODS

Groningen button and Provox 2 voice prostheses were inoculated with a mixture of bacteria and yeasts isolated from previously explanted Groningen button voice prostheses. After 5 h, separate throats were flushed with buttermilk, Yakult Light fermented milk drink, N-acetylcysteine or phosphate-buffered saline, which served as a control. After 7 days, the microflora on each voice prosthesis was determined.

RESULTS

On Groningen button voice prostheses, buttermilk, Yakult Light fermented milk drink and N-acetylcysteine all reduced the amount of both bacteria and yeasts. On Provox 2 voice prostheses, buttermilk, Yakult Light fermented milk drink and N-acetylcysteine reduced the amount of bacteria but, conversely, increased the amount of yeasts.

CONCLUSION

These in vitro experiments demonstrate that biofilm formation on voice prostheses is reduced in an artificial throat by the use of buttermilk, Yakult Light fermented milk drink and N-acetylcysteine. However, the structural differences between the type of voice prostheses may influence the ultimate effects.

Physicochemical properties and mechanism of drug release from ethyl cellulose matrix tablets prepared by direct compression and hot-melt extrusion

The objective of this research project was to determine the physicochemical properties and investigate the drug release mechanism from ethyl cellulose (EC) matrix tablets prepared by either direct compression or hot-melt extrusion (HME) of binary mixtures of water soluble drug (guaifenesin) and the polymer. Ethyl cellulose was separated into "fine" or "coarse" particle size fractions corresponding to 325-80 and 80-30 mesh particles, respectively. Tablets containing 30% guaifenesin were prepared at 10, 30, or 50 kN compaction forces and extruded at processing temperatures of 80-90 and 90-110 degrees C. The drug dissolution and release kinetics were determined and the tablet pore characteristics, tortuosity, thermal properties and surface morphologies were studied using helium pycnometry, mercury porosimetry, differential scanning calorimetry and scanning electron microscopy. The tortuosity was measured directly by a novel technique that allows for the calculation of diffusion coefficients in three experiments. The Higuchi diffusion model, Percolation Theory and Polymer Free Volume Theory were applied to the dissolution data to explain the release properties of drug from the matrix systems. The release rate was shown to be dependent on the ethyl cellulose particle size, compaction force and extrusion temperature.

[Development of throat clearing herbal teas]

Medicinal herbs in tea for throat clearing are used from ancient times. Taking into consideration the bronchial mucus secretion stimulating and antispasmodic, antimicrobial, antiphlogistic and stimulating effect on the ciliated epithelium two new formulations of throat clearing herbal tea were originated. The first formulation consists of liquorice roots, sweet fennel and thyme, and the second one consists of pine gemmae, thyme and elder flowers. The methods for identification and assay of the active substances of the components were adapted. The purity of the mixtures was regulated by the limitation of the loss on drying, total ash, microbial contamination, contamination with radionuclides, heavy metals, pesticides and foreign matter. Expiry date of both throat clearing herbal teas was confirmed to be 2 years.

[Effects of fudosteine, a new cysteine derivative, on airway secretion in rabbits and rats]

We examined the effects of fudosteine [(-)-(R)-2-amino-3-(3-hydroxypropylthio) propionic acid], a new cysteine derivative, on airway secretion in rabbits and rats. Indirect measurement of airway secretion in rabbits, which was expressed by the amount of dye excreted into the respiratory tract, was carried out according to the Sakuno's method, with some modifications. Fudosteine (500 mg/kg, p.o.) significantly increased the amount of dye excreted into the respiratory tract. As a direct method of measurement of airway secretion, the modified Perry and Boyd's method was used to collect respiratory tract fluid (RTF) in rabbits. Fudosteine (500 mg/kg, p.o.) significantly augmented the output volume of RTF, but there was no difference from the control in protein and phosphatidylcholine (PC) contents into RTF. On the other hand, fudosteine increased chloride ion concentration in broncho-alveolar lavage of rats. Fudosteine did not stimulate PC secretion in a primary culture of rat type II pneumocytes, and it did not have a mucolytic effect against gastric mucin in vitro. From the results described above, it was concluded that fudosteine may be a new cysteine derivative which offers a serous secretion.

Studies in enzyme cytochemistry I. Principles of cytochemical staining methods

Advances that could accrue from the introduction of photometric methods into cytochemical staining practice include the investigation, by cytophotometry, of the mechanism of enzyme action in situ and the possible identification of closely similar enzymes by the direct determination of their Michaelis-Menten constants in the cell or tissue. After brief mention of the fundamental limitations of stain cytochemistry associated with (i) enzyme specificity, and (ii) the need for preliminary treatment such as fixation, a study is made of the theoretical basis of those staining methods which can be classified under the scheme substrate enzymic → reaction stain precursor 'capture reaction' → with developing agent stain. These are considered in relation to a radially symmetrical model in which the enzyme is taken to be uniformly distributed in a spherical site, selected as the simplest that approximates to many actual sites. The overall process is simplified, without undue error, by division into stages. A brief survey of substrate penetration is followed by detailed study of the production, diffusion, and chemical removal of the stain precursor. Little is known about the mechanism of stain immobilization, but on the assumption of non-diffusibility, the stain density patterns are given for various values of the (first order) velocity constant of the capture reaction, diffusion coefficient of the stain precursor, and enzyme-site radius. A localization factor (degree of localization, F ) is defined, which gives an indication of the intrinsic localization possibilities of any cytochemical method. This has value in both theoretical and experimental study. Values for F have been calculated, corresponding to the kinetic and geometrical parameters mentioned above. In order to satisfy the objective requirements that emerge from the theory, certain generalizations may be made concerning the properties of prospective substrates. The substrate itself should not associate with protein, except possibly the specific enzyme species, but it should yield a stain precursor and a stain, both of which should associate strongly with protein, i. e. be highly substantive molecules. Unless precursor-protein association occurs, extremely high capture reaction velocities are necessary for precise enzyme mapping in small sites.

Novel therapy for COPD

The incidence of chronic obstructive pulmonary disease (COPD) is increasing throughout the world. Much less is known about the pathogenesis of COPD than that of asthma and there is little response to current therapy. Most patients with COPD have acquired their lung disease through smoking cigarettes, and the major step in management is to minimise further damage by stopping this habit. A number of therapies are being developed for the treatment of COPD; including new bronchodilators such as tiotropium bromide, agents to block inflammation induced by neutrophils and macrophages, as well as strategies to combat proteases and oxidants. The long-term goal is to provide therapy that retards the accelerated loss of lung function occurring in COPD. Development of novel therapies for COPD requires reliable Phase II decision making before entering large scale Phase III studies. The patient with COPD is often overlooked compared to their asthmatic counterpart, who benefit from an urgent need to identify novel targets and better therapy.

III. Relationships between solubility, molecular association and structure in indigoid dyes

The bearing of lipid solubilities and substantivities of dyes on the results of cytochemical staining reactions is briefly discussed. Solubilities of indigoid dyes in various lipids are qualitatively similar to those in sym tetrachloroethane. Quantitative determinations made in this solvent indicate that, in general, indigo and its 5:5΄- and 6:6΄-substituted derivatives are sparingly soluble, whereas the corresponding 4:4΄- and 7:7΄-substituted dyes are relatively very soluble. The enhanced solubilities of the latter dyes are consistent with the hypothesis that the substituents interfere with edge-to-edge hydrogen-bonded association otherwise present in indigo and its 5:5΄- and 6:6΄-substituted derivatives. This hypothesis is supported by mutually consistent results given by solubility, melting point and infra-red spectrographic studies. Indigoid dyes possessing small substituents in the 4:4΄-position, such as 4:4΄-dichloro-indigo, are highly substantive and therefore potentially of great value when formed in cytochemical staining reactions.

[Effects of ambroxol HCl on the guinea pig tracheal mucous secretion and the rat pulmonary surfactant secretion]

The effects of orally administered ambroxol HCl (ambroxol) on guinea pig tracheal mucous secretion and rat pulmonary surfactant secretion were investigated histologically and biochemically. Ambroxol significantly increased the number of active goblet cells in guinea pig tracheal epithelium and total mucopolysaccharide level. Moreover, ambroxol significantly increased the neutral mucopolysaccharide level and PAS-positive substance in the guinea pig tracheal submucosal glands. Ambroxol did not show a significant effect on the content of the total phosphatidylcholine in rat lung lavage fluid, while ambroxol significantly increased the ratio of disaturated phosphatidylcholine to total phosphatidylcholine. From these results, it is suggested that ambroxol increases both the tracheal mucous secretion, especially the neutral mucopolysaccharide, and pulmonary surfactant secretion and these effects reflect part of the expectorant mechanism of the drug.