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1.
Eur Respir J ; 2023 May 18.
Article in English | MEDLINE | ID: mdl-37202153

ABSTRACT

The incidence of newly developed interstitial lung abnormalities (ILA) and fibrotic ILA have not been previously reported.Trained thoracic radiologists evaluated 13 944 cardiac CT scans for the presence of ILA in 6197 Multi-Ethnic Study of Atherosclerosis longitudinal cohort study participants >45 years of age from 2000 to 2012. 5% of the scans were re-read by the same or a different observer in a blinded fashion. After exclusion of participants with ILA at baseline, incidence rates and incidence rate ratios for ILA and fibrotic ILA were calculated.The intra-reader agreement of ILA was 92.0% (Gwet AC1=0.912, ICC=0.982) and the inter-reader agreement of ILA was 83.5% (Gwet AC1=0.814; ICC=0.969). Incidence of ILA and fibrotic ILA was estimated to be 13.1 cases/1000 person-years and 3.5/1000 person-years, respectively. In multivariable analyses, age (HR 1.06 (1.05, 1.08), p <0.001; HR 1.08 (1.06, 1.11), p <0.001), high attenuation area (HAA) at baseline (HR 1.05 (1.03, 1.07), p <0.001; HR 1.06 (1.02, 1.10), p=0.002), and the MUC5B promoter SNP (HR 1.73 (1.17, 2.56) p=0.01; HR 4.96 (2.68, 9.15), p <0.001) were associated with incident ILA and fibrotic ILA, respectively. Ever smoking (HR 2.31 (1.34, 3.96), p= 0.002) and an IPF polygenic risk score (HR 2.09 (1.61-2.71), p<0.001) were associated only with incident fibrotic ILA.Incident ILA and fibrotic ILA were estimated by review of cardiac imaging studies. These findings may lead to wider application of a screening tool for atherosclerosis to identify preclinical lung disease.

4.
Pediatr Res ; 90(2): 335-340, 2021 08.
Article in English | MEDLINE | ID: mdl-33214672

ABSTRACT

BACKGROUND: Potentially, orally administered antibodies specific to enteric pathogens could be administered to infants to prevent diarrheal infections, particularly in developing countries where diarrhea is a major problem. However, to prevent infection, such antibodies would need to resist degradation within the gastrointestinal tract. METHODS: Palivizumab, a recombinant antibody specific to respiratory syncytial virus (RSV), was used in this study as a model for examining the digestion of neutralizing antibodies to enteric pathogens in infants. The survival of this recombinant IgG1 across digestion in 11 infants was assayed via an anti-idiotype ELISA and RSV F protein-specific ELISA. Concentrations were controlled for any dilution or concentration that occurred in the digestive system using mass spectrometry-based quantification of co-administered, orally supplemented, indigestible polyethylene glycol (PEG-28). RESULTS: Binding activity of Palivizumab IgG1 decreased (26-99%) across each phase of in vivo digestion as measured by both anti-idiotype and RSV F protein-specific ELISAs. CONCLUSION: Antibodies generated for passive protection of the infant gastrointestinal tract from pathogens will need to be more resistant to digestion than the model antibody fed to infants in this study, or provided in higher doses to be most effective. IMPACT: Binding activity of palivizumab IgG1 decreased (26-99%) across each phase of in vivo infant digestion as measured by both anti-idiotype and RSV F protein-specific ELISAs. Palivizumab was likely degraded by proteases and changes in pH introduced in the gut. Antibodies generated for passive protection of the infant gastrointestinal tract from pathogens will need to be more resistant to digestion than the model antibody fed to infants in this study, or provided in higher doses to be most effective. The monoclonal antibody IgG1 tested was not stable across the infant gastrointestinal tract. The observation of palivizumab reduction was unlikely due to dilution in the gastrointestinal tract. The results of this work hint that provision of antibody could be effective in preventing enteric pathogen infection in infants. Orally delivered recombinant antibodies will need to either be dosed at high levels to compensate for digestive losses or be engineered to better resist digestion. Provision of enteric pathogen-specific recombinant antibodies to at-risk infants could provide a new and previously unexplored pathway to reducing the infection in infants. The strategy of enteric recombinant antibodies deserves more investigation throughout medicine as a novel means for treatment of enteric disease targets.


Subject(s)
Antiviral Agents/metabolism , Digestion , Gastrointestinal Tract/metabolism , Palivizumab/metabolism , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Viruses/immunology , Administration, Oral , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/metabolism , Antibodies, Viral/immunology , Antibodies, Viral/metabolism , Antiviral Agents/administration & dosage , Drug Stability , Enzyme-Linked Immunosorbent Assay , Female , Host-Pathogen Interactions , Humans , Infant, Newborn , Male , Palivizumab/administration & dosage , Protein Stability , Respiratory Syncytial Virus Infections/immunology , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Viruses/pathogenicity
6.
J Funct Foods ; 73: 104115, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33101461

ABSTRACT

To help rationally design an antibody for oral administration, we examined how different isotypes (IgG, IgA and sIgA) with the same variable sequence affect antibody stability across digestion. We compared the degradation of recombinant palivizumab (IgG1), and recombinant IgA and sIgA versions of palivizumab spiked in human milk to the degradation of naturally-occurring anti-respiratory syncytial virus (RSV) sIgA/IgA and IgG in human milk from four donors across gastric and intestinal phases of an in vitro model of infant digestion via a validated RSV F protein ELISA. Palivizumab IgG and IgA formats were less stable than the sIgA version after complete simulated gastrointestinal digestion: palivizumab IgG, IgA and sIgA decreased across complete simulated gastrointestinal digestion by 55%, 48% and 28%, respectively. Naturally-occurring RSV F protein-specific IgG was stable across digestion, whereas naturally-occurring sIgA/IgA was stable in the gastric phase but decreased 33% in the intestinal phase of simulated digestion.

7.
Front Nutr ; 7: 136, 2020.
Article in English | MEDLINE | ID: mdl-32984396

ABSTRACT

Oral administration of enteric pathogen-specific immunoglobulins may be an ideal approach for preventing infectious diarrhea in infants and children. For oral administration to be effective, antibodies must survive functionally intact within the highly proteolytic digestive tract. As an initial step toward assessing the viability of this approach, we examined the survival of palivizumab, a recombinant monoclonal antibody (IgG1κ), across infant digestion and its ability to neutralize respiratory syncytial virus (RSV). Human milk and infant digestive samples contain substances known to interfere with the RSV neutralization assay (our selected functional test for antibody survival through digestion), therefore, antibody extraction from the matrix was required prior to performing the assay. The efficacy of various approaches for palivizumab purification from human milk, infant's gastric and intestinal digestates, including casein precipitation, salting out, molecular weight cut-off, and affinity chromatography (protein A and G) were compared. Affinity chromatography using protein G with high-salt elution followed by 30-kDa molecular weight cut-off centrifugal filtration was the most effective technique for purifying palivizumab from human milk and infant digestates with a high yield and reduced background interference for the viral neutralization assay. This work is broadly applicable to the optimal isolation of antibodies from human milk and infant digesta for viral neutralization assays, enables the examination of how digestion affects the viral neutralization capacity of antibodies within milk and digestive samples, and paves the way for assessment of the viability of oral administration of recombinant antibodies as a therapeutic approach to prevent enteric pathogen-induced infectious diarrhea in infants.

8.
Front Nutr ; 7: 130, 2020.
Article in English | MEDLINE | ID: mdl-32923453

ABSTRACT

Oral administration of engineered immunoglobulins has the potential to prevent enteric pathogen-induced diarrhea in infants. To prevent infection, these antibodies need to survive functionally intact in the proteolytic environment of the gastrointestinal tract. This research examined both ex vivo and in vivo the functional survival across infant digestion of palivizumab, a model FDA-approved recombinant antibody against respiratory syncytial virus (RSV) F protein. Palivizumab-fortified feed (formula or human milk), infant gastric, and intestinal samples were incubated to simulate in vivo digestion (ex vivo digestion). Palivizumab-fortified human milk was also fed to infants, followed by collection of gastric and intestinal samples (in vivo digestion). Palivizumab was purified from the samples of digestate using protein G spin columns followed by filtration through molecular weight cut-off membranes (30 kDa). Palivizumab functional survival across ex vivo and in vivo digestion was determined via an anti-idiotype ELISA and an RSV plaque reduction neutralization test. Palivizumab concentration and RSV neutralization capacity both decreased when incubated in intestinal samples (ex vivo study). The concentration and neutralization activity of orally-supplemented palivizumab also decreased across infant digestion (in vivo study). These results indicate that if recombinant IgGs were selected for oral supplementation to prevent enteric infections, appropriate dosing would need to account for degradation occurring in the digestive system. Other antibody formats, structural changes, or encapsulation could enhance survival in the infant gastrointestinal tract.

9.
Foods ; 9(6)2020 Jun 09.
Article in English | MEDLINE | ID: mdl-32526824

ABSTRACT

Orally delivered antibodies may be useful for the prevention of enteric pathogen infection, but to be effective they need to survive intact across digestion through the gastrointestinal tract. As a test case, we fed a recombinant human antibody, palivizumab, spiked into human milk to four infants and collected gastric, intestinal and stool samples. We identified a tryptic peptide from palivizumab (LLIYDTSK) that differs from all endogenous human antibodies and used this for quantitation of the intact palivizumab. To account for dilution by digestive fluids, we co-fed a non-digestible, non-absorbable molecule-polyethylene glycol 28-quantified it in each sample and used this value to normalize the observed palivizumab concentration. The palivizumab peptide, a stable isotope-labeled synthetic peptide and polyethylene glycol 28 were quantified via a highly sensitive and selective parallel-reaction monitoring approach using nano-liquid chromatography/Orbitrap mass spectrometry. On average, the survival of intact palivizumab from the feed to the stomach, upper small intestine and stool were 88.4%, 30.0% and 5.2%, respectively. This approach allowed clear determination of the extent to which palivizumab was degraded within the infant digestive tract. This method can be applied with some modifications to study the digestion of any protein.

10.
Nutrients ; 12(3)2020 Feb 27.
Article in English | MEDLINE | ID: mdl-32120792

ABSTRACT

To prevent infectious diarrhea in infants, orally-supplemented enteric pathogen-specific recombinant antibodies would need to resist degradation in the gastrointestinal tract. Palivizumab, a recombinant antibody specific to respiratory syncytial virus (RSV), was used as a model to assess the digestion of neutralizing antibodies in infant digestion. The aim was to determine the remaining binding activity of RSV F protein-specific monoclonal and naturally-occurring immunoglobulins (Ig) in different isoforms (IgG, IgA, and sIgA) across an ex vivo model of infant digestion. RSV F protein-specific monoclonal immunoglobulins (IgG, IgA, and sIgA) and milk-derived naturally-occurring Ig (IgG and sIgA/IgA) were exposed to an ex vivo model of digestion using digestive samples from infants (gastric and intestinal samples). The survival of each antibody was tested via an RSV F protein-specific ELISA. Ex vivo gastric and intestinal digestion degraded palivizumab IgG, IgA, and sIgA (p < 0.05). However, the naturally-occurring RSV F protein-specific IgG and sIgA/IgA found in human milk were stable across gastric and intestinal ex vivo digestion. The structural differences between recombinant and naturally-occurring antibodies need to be closely examined to guide future design of recombinant antibodies with increased stability for use in the gastrointestinal tract.


Subject(s)
Antibodies, Monoclonal , Antibodies, Viral , Milk, Human/immunology , Respiratory Syncytial Viruses/immunology , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacokinetics , Antibodies, Viral/administration & dosage , Antibodies, Viral/immunology , Digestion , Female , Humans , Immunoglobulin A, Secretory/administration & dosage , Immunoglobulin A, Secretory/immunology , Immunoglobulin G/administration & dosage , Immunoglobulin G/immunology , Infant, Newborn , Male
12.
New Microbes New Infect ; 33: 100621, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31908781

ABSTRACT

Predominance of genotype G3P[8] rotavirus was revealed for children and adults with diarrhoea in north-central Bangladesh for a 1-year period from September 2018. The G3P[8] rotaviruses were phylogenetically close to recent Indian strains, having antigenic variation in VP7 and VP4 compared with old Bangladeshi strains.

13.
Mymensingh Med J ; 29(1): 86-91, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31915341

ABSTRACT

Among nurses due to inadequate pain management knowledge and practice skills, children's pain is often under treated. This study aimed to examine the level of knowledge and practice on pediatric pain management among nurses in Bangladesh. This was a descriptive survey study involving total 150 clinical pediatric nurses from two Medical College Hospital and a University hospital in Bangladesh. The data collection tool consisted of demographic data form, 32-items nurses' knowledge. There were 32 true and false questions related to nurses' knowledge on pediatric pain management in Bangladesh. The response formats to each item for correct answer was 1 and incorrect answer 0. The total scores were categorized into three levels including low (0-20), moderate (21-23) and high (24 and above). The data collection tool consisted of demographic data form, 19-item practice related questionnaire on pediatric pain management. Nurses' practice on pediatric pain management contained 19 items with 5-points Likert's scale ranging from 1=Never practice to 5=constantly practice. For each item, a score of 5 was accorded for constantly and 1 for never. The score ranged from 19-95. The total scores were categorized into three levels including low (19-38), moderate (39-76) and high (77-95). The results demonstrated that most of the nurses' knowledge score on pediatric pain management was at moderate level (mean=21.50, SD=2.35). Nurses' practice on pediatric pain management was also at moderate level (mean=75.45, SD=8.24). The relationship between nurses' knowledge and practice was not significant. In addition, nurses' knowledge and practice with demographic variables; there was significant relationship between nurse's knowledge and existence of pain management protocol, nurses' practice and their current position in unit and with reading nursing journal. This study showed moderate level of knowledge and practice indicating that they need to be enhanced the knowledge and practice skills in pediatric pain management.


Subject(s)
Clinical Competence , Health Knowledge, Attitudes, Practice , Pain Management/nursing , Pediatric Nursing , Adult , Bangladesh , Child , Female , Humans , Male , Nurse's Role , Nursing Staff, Hospital , Pain , Surveys and Questionnaires
15.
J Microsc ; 276(1): 13-20, 2019 10.
Article in English | MEDLINE | ID: mdl-31498428

ABSTRACT

Portable, low-cost smartphone platform microscopic systems have emerged as a potential tool for imaging of various micron and submicron scale particles in recent years (Ozcan; Pirnstill and Coté; Breslauer et al.; Zhu et al.). In most of the reported works, it involves either the use of sophisticated optical set-ups along with a high-end computational tool for postprocessing of the captured images, or it requires a high-end configured smartphone to obtain enhanced imaging of the sample. Present work reports the working of a low-cost, field-portable 520× optical microscope using a smartphone. The proposed smartphone microscopic system has been designed by attaching a 3D printed compact optical set-up to the rear camera of a regular smartphone. By using cloud-based services, an image processing algorithm has been developed which can be accessed anytime through a mobile broadband network. Using this facility, the quality of the captured images can be further enhanced, thus obviating the need for dedicated computational tools for postprocessing of the images. With the designed microscopic system, an optical resolution ∼2 µm has been obtained. Upon postprocessing, the resolution of the captured images can be improved further. It is envisioned that with properly designed optical set-up in 3D printer and by developing an image processing application in the cloud, it is possible to obtain a low-cost, user-friendly, field-portable optical microscope on a regular smartphone that performs at par with that of a laboratory-grade microscope. LAY DESCRIPTION: With the ever-improving features both in hardware and software part, smartphone becomes ubiquitous in the modern civilised society with approximately 8.1 billion cell phone users across the world, and ∼40% of them can be considered as smartphones. This technology is undoubtedly the leading technology of the 21st century. Very recently, various researchers across the globe have utilised different sensing components embedded in the smartphone to convert it into a field-portable low-cost and user-friendly tool which can be used for different sensing and imaging purposes. By using simple optical components such as lens, pinhole, diffuser etc. and the camera of the smartphone, various groups have converted the phone into a microscopic imaging system. Again, by removing the camera lenses of the phone, holography images of microscopic particles by directly casting its shadows on the CMOS sensor on the phone has been demonstrated. The holographic images have subsequently been processed using the dedicated computational tool, and the original photos of the samples can be obtained. All the reported smartphone-based microscopic systems either suffer from relatively low field-of-view (FOV), resolution or it needs a high computational platform. Present work, demonstrate an alternative approach by which a reasonably good resolution (<2 µm) along with high optical magnification (520×) and a large FOV (150 µm) has been obtained on a regular smartphone. For postprocessing of the captured images an image processing algorithm has been developed in the cloud and the same can be accessed by the smartphone application, obviating the need of dedicated computational tool and a high-end configured smartphone for the proposed microscope. For the development of the proposed microscopic system, a simple optical set-up has been fabricated in a 3D printer. The set-up houses all the required optical components and the sample specimen with the 3D-printed XY stage, and it can be attached easily to the rear camera of the smartphone. Using the proposed microscopic system, enhanced imaging of USAF target and red blood cells have been successfully demonstrated. With the readily available optical components and a regular smartphone, the net cost involvement is significantly low (less than $250, including the smartphone). We envisioned that the designed system could be utilised for point-of-care diagnosis in resource-poor settings where access to the laboratory facilities is very limited.


Subject(s)
Blood Cells/cytology , Microscopy/instrumentation , Microscopy/methods , Printing, Three-Dimensional , Smartphone/instrumentation , Image Processing, Computer-Assisted/methods
16.
Acta Virol ; 63(2): 139-148, 2019.
Article in English | MEDLINE | ID: mdl-31230442

ABSTRACT

The pumpkin leaf curl disease is an emerging disease of pumpkin in Assam, India. Symptomatic pumpkin leaf samples from different locations were immunologically tested using Begomovirus specific antibody. PCR with the ELISA-positive samples, using Geminivirus universal primers amplified 1.4 kb virus-specific fragments. Sequence of these amplicons showed around 95% identity with squash leaf curl China virus-[Pumpkin: Varanasi] (SLCCV-Pumpkin: Varanasi EU573715). To investigate the possible functions of the viral proteins present in the fragment, the full-length C2 and C3 genes were conceptually translated and were subjected to in silico proteomic analyses. The phylogenetic analysis of both the proteins divulged the relationship of our isolate with related viruses and isolates. Multiple sequence alignment (MSA) of the proteins revealed the presence of the known viral conserved motifs, viz., zinc-finger (ZNF) motif [36CXCX(7)CX(6)H53], the arginine-rich nuclear localization signal (NLS) motif (28RRRR31) as well as the minimal activation domain in C2 protein. In the C3 protein, the 91LKYLD95 and the replication enhancer motif (30YFK32) were found to be conserved. Finally, 3-D models of the two proteins were predicted via ab initio approach and subsequently, the models were validated. To our knowledge, this study is a pioneering attempt to construct the ab initio 3-D models of two begomoviral proteins taking a SLCCV isolate as a model. Keywords: begomovirus; ELISA; ZNF motif; NLS motif; ab initio modelling.


Subject(s)
Begomovirus , Computer Simulation , Cucurbita , Viral Proteins , Begomovirus/classification , Begomovirus/genetics , Cucurbita/virology , India , Phylogeny , Proteomics , Sequence Analysis, DNA , Viral Proteins/genetics
17.
Mymensingh Med J ; 28(2): 328-332, 2019 Apr.
Article in English | MEDLINE | ID: mdl-31086147

ABSTRACT

Post Kala-azar Dermal Leishmaniasis (PKDL) is the sequel of visceral leishmaniasis in Indian subcontinent and may appear among patients with or without previous history of visceral leishmaniasis (VL). The aim of the study is to understand the male reproductive safety profile of miltefosine used for the treatment of Post Kala-azar Dermal Leishmaniasis (PKDL) in Bangladesh. From January 2017 to March 2017, an exploratory study was carried out on male fertility capacity in Bangladesh among male patients above 14 years old with PKDL treated with miltefosine. Twenty nine male patients were included to observe the effect of miltefosine on reproductive health. All PKDL patients had history of visceral leishmaniasis (VL) in different time periods. Among them three (10.3%) patients were unable to ejaculate semen. In semen analysis, 3 patients (10.3%) were found azoospermia (sperm count & motility- 0, viscosity- good, pH- 7 to 8), microscopically there was presence of RBC (5-15/HPF), WBC (8-15/HPF). Another 3 patients (10.3%) were found oligospermia (sperm count- 4.2 to 15.3 million/ml, motility- 20 to 50%, viscosity- good, pH- 6 to 9, RBC- 4 to 15/HPF, WBC- 4 to 15/HPF). The study documented some important findings in evaluating male infertility and selection of drug regimens in treating PKDL patients with miltefosine for 12 weeks.


Subject(s)
Antiprotozoal Agents/therapeutic use , Infertility, Male/chemically induced , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Visceral/drug therapy , Phosphorylcholine/analogs & derivatives , Adolescent , Antiprotozoal Agents/adverse effects , Bangladesh , Fertility , Humans , Male , Phosphorylcholine/adverse effects , Phosphorylcholine/therapeutic use , Treatment Outcome
19.
Rev Sci Instrum ; 89(10): 103111, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399881

ABSTRACT

A 3D printed smartphone based interferometric system is proposed, and its usability has been demonstrated by measuring small angular rotations. All necessary fringe processing and data analysis have been performed within the phone itself using custom designed application developed in an android platform. The main objective of the proposed work is to demonstrate the usability of modern smartphone and 3D printing technology for optical interferometric applications. The smartphone camera has been used to record the interference fringes which has been formed due to the change in the optical path difference (OPD) between light rays reflected from the top and bottom surface of a microscopic glass slide. The angular variation of the slide causes a detectable change in the OPD between the interfering beams which subsequently would cause a variation in the fringe pattern. By evaluating necessary interferometric parameters, small angular rotation can be computed within the smartphone application. With the designed smartphone based interferometric system, angular rotation as small as 0.02° can be measured accurately and reliably having a dynamic range of -3.68° to 3.68°. Due to the involvement of the smartphone as a platform for recording as well as onboard fringe processing, the designed interferometric system can be visualized as a truly field portable tool for different optical metrological applications.

20.
Biomed Microdevices ; 19(4): 98, 2017 Nov 07.
Article in English | MEDLINE | ID: mdl-29116412

ABSTRACT

Thin and flexible polymeric membranes play a critical role in tissue engineering applications for example organs-on-a-chip. These flexible membranes can enable mechanical stretch of the engineered tissue to mimic organ-specific biophysical features, such as breathing. In this work, we report the fabrication of thin (<20 µm), stretchable, and biocompatible polyurethane (PU) membranes. The membranes were fabricated using spin coating technique on silicon substrates and were mounted on a frame for ease of device integration and handling. The membranes were characterized for their optical and elastic properties and compatibility with cell/tissue culture. It was possible to apply up to 10 kilopascal (kPa) pressure to perform cyclic stretch on 4 mm-diameter membranes for a period of 2 weeks at 0.2 hertz (Hz) frequency without mechanical failure. Adenocarcinomic human alveolar basal epithelial (A549) cells were cultured on the apical side of the PU membrane. The morphology and viability of the cells were comparable to those of cells cultured on standard tissue culture plates. Our experiments suggest that the stretchable PU membrane will be broadly useful for various tissue engineering applications in vitro.


Subject(s)
Membranes/chemistry , Polyurethanes/chemistry , Tissue Engineering , A549 Cells , Biocompatible Materials/chemistry , Biomimetic Materials , Cell Survival , Humans , Lab-On-A-Chip Devices , Models, Theoretical , Polymers/chemistry , Tissue Scaffolds
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