Stiffness assisted cell-matrix remodeling trigger 3D mechanotransduction regulatory programs

Engineered matrices provide a valuable platform to understand the impact of biophysical factors on cellular behavior such as migration, proliferation, differentiation, and tissue remodeling, through mechanotransduction. While recent studies have identified some mechanisms of 3D mechanotransduction, there is still a critical knowledge gap in comprehending the interplay between 3D confinement, ECM properties, and cellular behavior. Specifically, the role of matrix stiffness in directing cellular fate in 3D microenvironment, independent of viscoelasticity, microstructure, and ligand density remains poorly understood. To address this gap, we designed a nanoparticle crosslinker to reinforce collagen-based hydrogels without altering their chemical composition, microstructure, viscoelasticity, and density of cell-adhesion ligand and utilized it to understand cellular dynamics. This crosslinking mechanism utilizes nanoparticles as crosslink epicenter, resulting in 10-fold increase in mechanical stiffness, without other changes. Human mesenchymal stem cells (hMSCs) encapsulated in 3D responded to mechanical stiffness by displaying circular morphology on soft hydrogels (5 kPa) and elongated morphology on stiff hydrogels (30 kPa). Stiff hydrogels facilitated the production and remodeling of nascent extracellular matrix (ECM) and activated mechanotransduction cascade. These changes were driven through intracellular PI3AKT signaling, regulation of epigenetic modifiers and activation of YAP/TAZ signaling. Overall, our study introduces a unique biomaterials platform to understand cell-ECM mechanotransduction in 3D for regenerative medicine as well as disease modelling.

The Role of Preprocedure Genetic Counseling in Pregnancies Interrupted for Fetal Abnormalities

OBJECTIVE

 Congenital birth defects affect 3 to 5% of pregnancies. Genetic counseling can help patients navigate the testing process and understand results. The study objective was to identify predictors and utility of genetic counseling at the time of pregnancy termination. Additionally, we aimed to see what proportion of patients would benefit from additional testing based on the results of the genetic testing.

STUDY DESIGN

 This was a retrospective cohort review of all terminations performed for fetal anomalies by an academic center from July 2016 to May 2020. Indications were stratified by abnormal serum screening or types of abnormal ultrasound findings. Data were abstracted regarding uptake of genetic counseling and testing results. Abnormal results that warranted additional testing regarding recurrence risks were noted. Multivariable logistic regression was performed to identify predictors of receipt of genetic counseling and testing.

RESULTS

 Of 387 patients, 57% (n = 220) received preprocedure genetic counseling and 43% (n = 167) did not. Among patients who received diagnostic testing, 62% (n = 194) had genetic counseling compared with 38% (n = 121) without counseling (adjusted odds ratio 2.46, 95% confidence interval [1.41-4.29], p < 0.001). Among the entire cohort, 38% (n = 148) had suspected aneuploidy based on serum screening. Of these, 89% (n = 132/148) had definitive testing, 92% (n = 122/132) confirming the aneuploidy. Among the other 68% (n = 239) with structural anomalies, 76% (n = 183) had diagnostic testing with 29% (n = 53) yielding an abnormal result. Among those fetuses with structural anomalies, 36% (n = 19/53) of genetic diagnoses warranted additional parental testing because of risk of recurrence compared with only 2% (n = 2/122) of patients with abnormal serum screening results alone.

CONCLUSION

 Genetic counseling was associated with increased uptake of diagnostic testing, which yielded useful information and prompted additional testing. This is important for determining etiology and recurrence risk and should be offered to patients presenting for termination for fetal indications, as well as providing diagnostic closure for patients.

KEY POINTS

· Genetic counseling increases the uptake of diagnostic testing in patients with fetal anomalies.. · Patients with ultrasound anomalies received less diagnostic testing despite actionable results 36% of the time.. · Genetic testing is invaluable for recurrence risk counseling even if patients chose to terminate..

Reduced mitophagy is an early feature of NAFLD and liver-specific PARKIN knockout hastens the onset of steatosis, inflammation and fibrosis

Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of pathologies that includes steatosis, steatohepatitis (NASH) and fibrosis and is strongly associated with insulin resistance and type 2 diabetes. Changes in mitochondrial function are implicated in the pathogenesis of NAFLD, particularly in the transition from steatosis to NASH. Mitophagy is a mitochondrial quality control mechanism that allows for the selective removal of damaged mitochondria from the cell via the autophagy pathway. While past work demonstrated a negative association between liver fat content and rates of mitophagy, when changes in mitophagy occur during the pathogenesis of NAFLD and whether such changes contribute to the primary endpoints associated with the disease are currently poorly defined. We therefore undertook the studies described here to establish when alterations in mitophagy occur during the pathogenesis of NAFLD, as well as to determine the effects of genetic inhibition of mitophagy via conditional deletion of a key mitophagy regulator, PARKIN, on the development of steatosis, insulin resistance, inflammation and fibrosis. We find that loss of mitophagy occurs early in the pathogenesis of NAFLD and that loss of PARKIN accelerates the onset of key NAFLD disease features. These observations suggest that loss of mitochondrial quality control in response to nutritional stress may contribute to mitochondrial dysfunction and the pathogenesis of NAFLD.

Lung Ultrasound: A Complementary Imaging Tool for Chest X-Ray in the Evaluation of Dyspnea

The present study was designed to evaluate the spectrum of imaging findings seen on chest ultrasonography in patients presenting with dyspnea and verify the concordance between chest X-ray and chest ultrasound.

Methods Fifty-three patients presenting with dyspnea were included in this study. Patients with known/suspected cardiac disease were excluded from the study. All patients underwent chest X-ray and chest ultrasound, reported by two different investigators. The concordance was analyzed using Cohen's kappa value with a ‘p-value’ less than 0.05 considered statistically significant.

Results Among the fifty-three patients with dyspnea, five diagnostic pathologies were evaluated. Concordance between lung ultrasound and chest X-ray for diagnosis of pneumonia, pneumothorax, acute exacerbation of COPD/severe asthma, and diffuse alveolar interstitial syndrome was found to be high with Cohen's kappa value > 0.8 (p < 0.01). Ultrasound was able to correctly diagnose more cases of pneumothorax and pulmonary edema compared with chest X-ray with sensitivity and negative predictive value of 100%. Chest X-ray was found to be superior in correctly diagnosing COPD. The difference was, however, not statistically significant. Similarly, no statistically significant difference could be inferred between the diagnostic value of ultrasound and Chest X-ray in the diagnosis of pneumonia or pleural effusion.

Conclusions A high concordance was noted between ultrasound and chest X-ray for diagnosis of all pathologies studied (p < 0.01), the highest noted in pneumonia/pleural effusion and diffuse interstitial syndrome (κ = 0.9). Hence, ultrasound may be considered a complimentary imaging modality for Chest-X-ray in the evaluation of dyspnea.

Dissociation of nanosilicates induces downstream endochondral differentiation gene expression program

Bioactive materials harness the body's innate regenerative potential by directing endogenous progenitor cells to facilitate tissue repair. Dissolution products of inorganic biomaterials provide unique biomolecular signaling for tissue-specific differentiation. Inorganic ions (minerals) are vital to biological processes and play crucial roles in regulating gene expression patterns and directing cellular fate. However, mechanisms by which ionic dissolution products affect cellular differentiation are not well characterized. We demonstrate the role of the inorganic biomaterial synthetic two-dimensional nanosilicates and its ionic dissolution products on human mesenchymal stem cell differentiation. We use whole-transcriptome sequencing (RNA-sequencing) to characterize the contribution of nanosilicates and its ionic dissolution products on endochondral differentiation. Our study highlights the modulatory role of ions in stem cell transcriptome dynamics by regulating lineage-specific gene expression patterns. This work paves the way for leveraging biochemical characteristics of inorganic biomaterials to direct cellular processes and promote in situ tissue regeneration.

Genetics of Ataxias in Indian Population: A Collative Insight from a Common Genetic Screening Tool

Cerebellar ataxias (CAs) represent a group of autosomal dominant and recessive neurodegenerative disorders affecting cerebellum with or without spinal cord. Overall, CAs have preponderance for tandem nucleotide repeat expansions as an etiological factor (10 TREs explain nearly 30-40% of ataxia cohort globally). The experience of 10 years of common genetic ataxia subtypes for ≈5600 patients' referrals (Pan-India) received at a single center is shared herein. Frequencies (in %, n) of SCA types and FRDA in the sample cohort are observed as follows: SCA12 (8.6%, 490); SCA2 (8.5%, 482); SCA1 (4.8%, 272); SCA3 (2%, 113); SCA7 (0.5%, 28); SCA6 (0.1%, 05); SCA17 (0.1%, 05), and FRDA (2.2%, 127). A significant amount of variability in TRE lengths at each locus is observed, we noted presence of biallelic expansion, co-occurrence of SCA-subtypes, and the presence of premutable normal alleles. The frequency of mutated GAA-FRDA allele in healthy controls is 1/158 (0.63%), thus an expected FRDA prevalence of 1:100 000 persons. The data of this study are relevant not only for clinical decision making but also for guidance in direction of genetic investigations, transancestral comparison of genotypes, and lastly provide insight for policy decision for the consideration of SCAs under rare disease category.

Complement Factor H Loss in RPE Cells Causes Retinal Degeneration in a Human RPE-Porcine Retinal Explant Co-Culture Model

Age-related Macular degeneration (AMD) is a degenerative disease of the macula affecting the elderly population. Treatment options are limited, partly due to the lack of understanding of AMD pathology and the lack of suitable research models that replicate the complexity of the human macula and the intricate interplay of the genetic, aging and lifestyle risk factors contributing to AMD. One of the main genetic risks associated with AMD is located on the Complement Factor H (CFH) gene, leading to an amino acid substitution in the Factor H (FH) protein (Y402H). However, the mechanism of how this FH variant promotes the onset of AMD remains unclear. Previously, we have shown that FH deprivation in RPE cells, via CFH silencing, leads to increased inflammation, metabolic impairment and vulnerability toward oxidative stress. In this study, we established a novel co-culture model comprising CFH silenced RPE cells and porcine retinal explants derived from the visual streak of porcine eyes, which closely resemble the human macula. We show that retinae exposed to FH-deprived RPE cells show signs of retinal degeneration, with rod cells being the first cells to undergo degeneration. Moreover, via Raman analyses, we observed changes involving the mitochondria and lipid composition of the co-cultured retinae upon FH loss. Interestingly, the detrimental effects of FH loss in RPE cells on the neuroretina were independent of glial cell activation and external complement sources. Moreover, we show that the co-culture model is also suitable for human retinal explants, and we observed a similar trend when RPE cells deprived of FH were co-cultured with human retinal explants from a single donor eye. Our findings highlight the importance of RPE-derived FH for retinal homeostasis and provide a valuable model for AMD research.

Emerging 2D Nanomaterials for Biomedical Applications

Two-dimensional (2D) nanomaterials are an emerging class of biomaterials with remarkable potential for biomedical applications. The planar topography of these nanomaterials confers unique physical, chemical, electronic and optical properties, making them attractive candidates for therapeutic delivery, biosensing, bioimaging, regenerative medicine, and additive manufacturing strategies. The high surface-to-volume ratio of 2D nanomaterials promotes enhanced interactions with biomolecules and cells. A range of 2D nanomaterials, including transition metal dichalcogenides (TMDs), layered double hydroxides (LDHs), layered silicates (nanoclays), 2D metal carbides and nitrides (MXenes), metal-organic framework (MOFs), covalent organic frameworks (COFs) and polymer nanosheets have been investigated for their potential in biomedical applications. Here, we will critically evaluate recent advances of 2D nanomaterial strategies in biomedical engineering and discuss emerging approaches and current limitations associated with these nanomaterials. Due to their unique physical, chemical, and biological properties, this new class of nanomaterials has the potential to become a platform technology in regenerative medicine and other biomedical applications.

Practical consensus recommendations regarding the use of hormonal therapy in metastatic breast cancer

Metastatic breast cancer (MBC) is cancer that has spread from the breast to another part of the body or has come back in another distant location. Treatment options for MBC depend on several factors. One of these factors is the levels of hormone receptors (HRs) in the tumor. Cancers with high levels of HRs, called HR-positive, use the hormones estrogen and progesterone to grow and spread. Hormonal therapy is a type of treatment specifically for HR-positive breast cancer. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at these practical consensus recommendations in regards with the use of hormonal therapy and the management of HR-positive MBC for the benefit of community oncologists.

Characterisation and validation of the 8-fold quadrant dissected human retinal explant culture model for pre-clinical toxicology investigation

One of the major challenges in studying ocular toxicology is a lack of clinically-relevant retinal experimental models. In this study we describe the use of an in vitro human retinal explant strategy to generate a reproducible experimental model with utility in neuro-toxicity retinal studies. A retinal dissection strategy, referred to as the 8 fold quadrant dissection, was developed by dissecting human donor retinas into 4 fragments through the fovea in order to obtain 8 experimentally reproducible retinal explants from a single donor. This quadrant dissection gave rise to equivalent proportions of CD73+ photoreceptors and CD90+ ganglion cells in 8 fragments from a single donor and this remained stable for up to 3 days in culture. Major retinal cell types continued to be observed after 8 weeks in culture, despite breakdown of the retinal layers, suggesting the potential to use this model in long-term studies where observation of individual cell types is possible. The utility of this system was examined in a proof of principle neuro-toxicology study. We showed reproducible induction of toxicity in photoreceptors and retinal ganglion cells by glutamate, cobalt chloride and hydrogen peroxide insults, and observed the therapeutic positive effects of the administration of memantine, formononetin and trolox. The quadrant dissected human retinal explants have the potential to be used in toxicology studies in human ocular diseases.

Guar gum modified upconversion nanocomposites for colorectal cancer treatment through enzyme-responsive drug release and NIR-triggered photodynamic therapy

Multimodal therapeutic approach towards colorectal cancer (CRC) holds great promise. There is, however, no convincing strategy reported to date that employs a multimodal strategy in CRC treatment. The present study reports an intense green-emitting core-shell photoluminescent upconversion (CSGU) nanocrystal engineered to synergistically perform photodynamic and enzyme-triggered delivery of the chemotherapeutic agent for an enhanced therapeutic outcome on HT-29 colon carcinoma cells in vitro. The photodynamic activity is achieved by the energy transfer between CSGU and the chemically conjugated Rose Bengal (RB) molecules that are further protected by a mesoporous silica (MS) layer. The chemical assay demonstrates a remarkable FRET mediated generation of ¹O₂ under NIR (980 nm) excitation. The outermost MS layer of the nanoplatform is utilized for the loading of the 5FU anticancer drug, which is further capped with a guar gum (GG) polysaccharide polymer. The release of the 5FU is specifically triggered by the degradation of the GG cap by specific enzymes secreted from colonic microflora, which otherwise showed 'zero-release behavior' in the absence of any enzymatic trigger in various simulated gastro-intestinal (GI) conditions. Furthermore, the enhanced therapeutic efficacy of the nanoplatform (CSGUR-MSGG/5FU) was evaluated through in vitro studies using HT-29 CRC cell lines by various biochemical and microscopic assays by the simultaneous triggering effect of colonic enzyme and 980 nm laser excitation. In addition, the strong visible emission from the nanoplatform has been utilized for NIR-induced cellular bioimaging.

Near-Infrared-Triggered Photodynamic, Photothermal, and on Demand Chemotherapy by Multifunctional Upconversion Nanocomposite

In an attempt to integrate photodynamic therapy (PDT) with photothermal therapy and chemotherapy for enhanced anticancer activity, we have rationally synthesized a multifunctional upconversion nanoplatform using NaYF₄:Yb/Tm/Er/Fe nanoparticles (NPs) as the core and NaYbF₄:1% Tm as a shell. The as-synthesized core-shell upconversion (CSU) NPs exhibited diverse and enhanced photoluminescence emissions in a wide range (UV to NIR) consequent upon Fe³⁺ doping in the core and fabrication of an active shell. Subsequently, CSU was first decorated with titania NPs as photosensitizers. Next, the mesoporous silica (MS) shell loaded with doxorubicin (DOX) via a photocleavable Ru complex as the gating molecule was developed around titania-containing CSU. Finally, gold nanorods (GNRs) with localized surface plasmon resonance (LSPR) at 800 nm were incorporated around the MS layer to obtain the multifunctional nanoplatform. We demonstrated that the UV, blue, and NIR emissions from the CSU produced ROS-mediated PDT through titania activation, induced DOX release through photocleavage of the Ru complex, and generated hyperthermia by LSPR activity of GNRs, respectively, upon a single NIR excitation through FRET. The therapeutic efficacy was validated on HeLa cell lines in vitro by various microscopic and biochemical studies under a significantly milder NIR irradiation and lower dosage of the nanoplatforms, which have been further demonstrated as diagnostic nanoprobes for cell imaging.

Gene therapy and the adeno-associated virus in the treatment of genetic and acquired ophthalmic diseases in humans: Trials, future directions and safety considerations

Voretigene neparvovec-rzyl was recently approved for the treatment of Leber congenital amaurosis, and the use of gene therapy for eye disease is attracting even greater interest. The eye has immune privileged status, is easily accessible, requires a reduced dosage of therapy due to its size and is highly compartmentalized, significantly reducing systemic spread. Adeno-associated virus (AAV), with its low pathogenicity, prolonged expression profile and ability to transduce multiple cell types, has become the leading gene therapy vector. Target diseases have moved beyond currently untreatable inherited dystrophies to common, partially treatable acquired conditions such as exudative age-related macular degeneration and glaucoma, but use of the technology in these conditions imposes added obligations for caution in vector design. This review discusses the current status of AAV gene therapy trials in genetic and acquired ocular diseases, and explores new scientific developments, which could help ensure effective and safe use of the therapy in the future.

Retinal explant culture: A platform to investigate human neuro-retina

The retina is the tissue responsible for light detection, in which retinal neurons convert light energy into electrical signals to be transported towards the visual cortex. Damage of retinal neurons leads to neuronal cell death and retinal pathologies, compromising visual acuity and eventually leading to irreversible blindness. Models of retinal neurodegeneration include 2D systems like cell lines, disassociated cultures and co-cultures, and 3D models like organoids, organotypic retinal cultures and animal models. Of these, ex vivo human retinal cultures are arguably the most suitable models for translational research as they retain complex inter-cellular interactions of the retina and precisely mimic in-situ responses. In this review, we summarize the distinguishing features of the human retina which are important to preserve in experimental culture, the historical development of human retinal culture systems, the factors affecting ex vivo human retinal culture and the applications and challenges associated with current methods of human retinal explant culture.

Anti-quorum sensing and antibiofilm potential of Alternaria alternata, a foliar endophyte of Carica papaya, evidenced by QS assays and in-silico analysis

In the present study, secondary metabolites from an endophytic fungus, Alternaria alternata, colonizing Carica papaya, demonstrated antiquorum sensing properties against Pseudomonas aeruginosa. This study reports the antagonistic effects of fungal crude extract of A. alternata against the various quorum sensing (QS) associated virulent factors such as percentage decrease in production of pyocyanin, alginate, chitinase and rhamnolipid; significant decrease in proteases activity such as LasA protease activity, staphylolytic activity, Las B elastase; and a marked decrease in biofilm formation and associated factors such as exopolysaccharide (EPS) production and cell surface hydrophobicity (CSH). Further, motility pattern i.e., swimming and swarming was also found to be inhibited. This down regulation of QS and associated factors are further supported by in-silico analysis of interaction between QS receptor LasR and bioactive molecules viz., sulfurous acid, 2-propyl tridecyl ester and 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester present in fungal crude extract, found based on GCMS analysis, sketches the modulating ability of QS expression. This is the first report on an endophytic fungus of C. papaya having a role in QS inhibition against P. aeruginosa and lays a platform to explore further the endophytes for potent therapeutic agents in QS.

Electron paramagnetic resonance and photoluminescence investigation on ultraviolet-emitting gadolinium-ion-doped CaAl₁₂O₁₉ phosphors

The gadolinium doped CaAl12O19 phosphor has been prepared by a low temperature solution combustion method in a short time and characterized using powder X-ray diffraction, energy dispersive analysis of X-ray mapping, electron paramagnetic resonance (EPR) and photoluminescence spectroscopic techniques. EPR and optical analysis of the sample confirm the presence of Gd(3+) in the CaAl12O19 matrix.

Reversible symptoms and clearance of mutant prion protein in an inducible model of a genetic prion disease in Drosophila melanogaster

Prion diseases are progressive disorders that affect the central nervous system leading to memory loss, personality changes, ataxia and neurodegeneration. In humans, these disorders include Creutzfeldt-Jakob disease, kuru and Gerstmann-Straüssler-Scheinker (GSS) syndrome, the latter being a dominantly inherited prion disease associated with missense mutations in the gene that codes for the prion protein. The exact mechanism by which mutant prion proteins affect the central nervous system and cause neurological disease is not well understood. We have generated an inducible model of GSS disease in Drosophila melanogaster by temporally expressing a misfolded form of the murine prion protein in cholinergic neurons. Flies accumulating this mutant protein develop motor abnormalities which are associated with electrophysiological defects in cholinergic neurons. We find that, upon blocking the expression of the mutant protein, both behavioral and electrophysiological defects can be reversed. This represents the first case of reversibility reported in a model of genetic prion disease. Additionally, we observe that endogenous mechanisms exist within Drosophila that are capable of clearing the accumulated prion protein.

Kikuchi's disease: an uncommon cause of cervical lymphadenopathy

Kikuchi Fujimoto's disease is a benign self limiting disorder presenting with localised cervical lymphadenopathy, fever, weight loss and night sweats. It is a rare disease with worldwide distribution but commonly reported from Asia. It is diagnosed by excision biopsy of the lymph nodes. Clinical features suggest a viral aetiology though not proven. It is often misdiagnosed as either systemic lupus erythematosus or malignant lymphoma. Better understanding as well as high clinical suspicion would aid in the diagnosis of the disease. Treatment is mainly symptomatic, with non-steroidal analgesics and antipyretics. Corticosteroids are rarely indicated. Although patients show a spontaneous recovery in 1-4 months, a follow-up of several years would be required to study the development of SLE in these patients.

Hypokalaemic paralysis and normocalcaemic tetany--a rare presentation of Sjogren's syndrome

38 year old woman was admitted with acute onset of quadriplegia. Biochemical investigation revealed severe hypokalaemia with hyperchloraemic metabolic acidosis, alkaline urine, and positive urinary anion gap which are the hallmark of distal tubular acidosis. In addition she also had hypophosphataemia, normoglycaemic glycosuria, aminoaciduria, and hyperphosphaturia suggestive of proximal tubular dysfunction. Further evaluation confirmed the diagnosis of Sjogren's syndrome. Interestingly our patient also had carpopedal spasm despite normal calcium and magnesium level. Quadriplegia and carpopedal spasm improved with correction of hypokalaemia and acidosis. Proximal tubular abnormalities (except albuminuria) were normalised at the time of discharge. Distal tubular acidosis is a well known renal manifestation of Sjogren's syndrome. But this type of transient proximal tubular dysfunction with distal tubular acidosis in Sjogren's syndrome is very rare and hypokalaemic tetany also deserves mention.

"Herbal remedy is natural and safe"--truth or myth?

Neem oil is often used externally as a traditional medicine in India. Its ingestion, even in small doses produces toxic effects like severe metabolic acidosis, seizures, renal failure and encephalopathy. Management is supportive and prognosis is generally good but fatalities may occur. Herein we report an unusual case of neem oil toxicity in a previously normal adult.

Protein losing enteropathy in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic immunologic disorder that may affect multiple organ systems and present with myriad of clinical features. Gastro-intestinal (GI) manifestations are oral ulcers, dysphagia and abdominal pain caused by autoimmune peritonitis/intestinal vasculitis. Hypoalbuminaemia due to GI loss is uncommon. Protein losing enteropathy (PLE) is a group of clinical entities where there is loss of protein through GI tract. PLE due to SLE is rare but it can be the initial manifestation. Patients usually present with pedal oedema mimicking nephrotic syndrome clinically. It is diagnosed by excluding other causes of hypoalbuminaemia. Radio nucleotide labelled albumin scan is useful in confirming albumin loss through GI tract. Often there is a good response to corticosteroids and immunosuppressive drugs. Here we present two SLE patients whose presenting manifestation was protein losing enteropathy and both improved with corticosteroids.

Atrial flutter and pericarditis--a rare complication of right lobe amoebic liver abscess

A 38 year old gentleman presented with fever and right hypochondrial pain. On further evaluation he was detected to have an amoebic liver abscess (ALA) in the right lobe of the liver. The abscess yielded anchovy sauce pus on percutaneous drainage. Following the percutaneous drainage the patient developed tachycardia. Electrocardiogram revealed atrial flutter with rapid ventricular rate and ST elevation in all leads suggestive of pericarditis. The atrial flutter was reverted to sinus rhythm by cardioversion. The patient then had an uncomplicated convalescence. Amoebic pericarditis, though rare, is a serious complication of amoebic liver abscess. Pericardial complications are usually seen with left lobe liver abscess due to its proximity. Both pericarditis and cardiac arrhythmias due to amoebic liver abscess especially from right lobe are very rare.

Disseminated infection with Strongyloides stercoralis in a diabetic patient

A 58-year-old male diabetic who was operated for carcinoma larynx 4 years back was admitted with exertional dyspnoea and bilateral leg swelling for the past 2 years. Over the last 2 months, there was a progressive worsening of symptoms. Echocardiography done 2 years back showed pericardial effusion. Echo done during the current admission also showed pericardial effusion with preserved left ventricular function; cytological examination of the pericardial fluid showed larvae of Strongyloides stercoralis. He was treated with antinematodal drugs. A follow-up echo done at discharge showed no pericardial effusion and the patient was completely asymptomatic. To our knowledge, this is the first reported case of Strongyloides pericardial effusion in a diabetic patient.

Blister beetle dermatitis

Blister beetle dermatitis or paederus dermatitis is an irritant contact dermatitis due to accidental crush of insects belonging to paederus family on the skin. The characteristic features of blister beetle dermatitis are linear erythematous itchy vesicles over the exposed parts of body and kissing lesions. This condition is commonly seen during or after rainy season. The treatment is removal of irritant by gentle washing and topical steroids. It is often misdiagnosed and causes significant morbidity among the rural population.

Alpha-fetoprotein as a tumor marker in hepatocellular carcinoma: investigations in south Indian subjects with hepatotropic virus and aflatoxin etiologies

OBJECTIVES

The prevalence of hepatitis B virus (HBV) is reportedly the main cause of hepatocellular carcinoma (HCC) in India, where hepatitis C virus (HCV)-associated HCC is believed to be relatively less prevalent. We verified the usefulness of alpha-fetoprotein (AFP) as a tumor marker and analyzed the influence of viral etiology on AFP levels in HCC.

METHODS

Of a total of 1012 cases with liver disease, 202 were investigated for the presence of AFP (142 HCC cases, 30 cirrhosis cases, and 30 chronic liver disease (CLD) cases). In addition, serum samples from 30 healthy patients, 30 hepatitis B surface antigen (HBsAg) carriers, and 30 acute viral hepatitis cases were included as controls. AFP was quantitatively determined using a commercial ELISA (Quorum Diagnostics, Canada). Out of the 142 HCC cases screened for AFP, aflatoxin B1 (AFB1) detection was carried out in 38 HCC cases using an in-house immunoperoxidase test.

RESULTS

In HBV and HCV co-infected HCC cases, the AFP positivity was 85.7%. In HBV alone-associated HCC, the positivity was 62.9%, and 54.5% of AFB1 positive HCC cases showed AFP positivity. In HBV and HCV negative HCC cases, the positivity was 20.5%, and in HCV-associated HCC it was 17.6%. The HBV/HCV co-infected group and HBV alone positive HCC cases had significantly elevated levels of AFP. When AFP positivity was analyzed based on the marker profile of HBV, 89.7% of AFP positive cases were HBV-DNA positive.

CONCLUSIONS

The overall positivity pattern of AFP in HCC does indicate that higher levels of AFP are observed with hepatitis virus positivity, especially with HBV. Further studies must be carried out to correlate the serum levels of AFP with the size, number, and degree of differentiation of HCC nodules.

Prevalence of aflatoxin B1 in liver biopsies of proven hepatocellular carcinoma in India determined by an in-house immunoperoxidase test

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death in the world. The incidence of HCC in India is reportedly low and varies from 0.2 to 1.9 %. Aflatoxins, secondary metabolites produced by Aspergillus flavus and Aspergillus parasiticus, are potent human carcinogens implicated in HCC. The prevalence of aflatoxin B1 (AFB1) as co-carcinogen was analysed using an in-house immunoperoxidase test in 31 liver biopsies and 7 liver-resection specimens from histopathologically proven HCC, and in 15 liver biopsies from cirrhosis patients (control group). Serum was tested for hepatitis B and C serological markers using commercial assays, and for AFB1 using an in-house ELISA with a sensitivity of approximately 1 ng ml(-1) for AFB1. In spite of positive AFB1 immunostaining in HCC cases, all serum specimens, from both HCC and the control groups, were AFB1-negative. There were 18 (58.1 %) HCC cases that revealed AFB1 in liver biopsies; 68.8 % (n=11) of non-B non-C hepatitis cases with HCC and 46.1 % (n=6) of the hepatitis B surface-antigen-positive subjects were positive for AFB1. Out of the two hepatitis B/hepatitis C virus co-infected cases, one was positive for AFB1. Of seven tumour-resection samples, six were positive for AFB1. Only one case revealed AFB1 in the non-tumour area of the resected material. Thus AFB1 staining was significantly associated with tumour tissue (P=0.03). Aflatoxins proved to have a significant association with HCC in this peninsular part of the subcontinent. The impact seems to be a cumulative process, as revealed by the AFB1 deposits in HCC liver tissue, even though the serum levels were undetectable.

Antidiabetic and antihyperlipemic effects of Clemeo felina

Petroleum ether and benzene extracts of Clemeo felina, given orally at doses of 300 mg kg(-1) day(-1) for 30 days, were found to be antidiabetic and antihyperlipemic on alloxan diabetic rats. Moreover, a significant decrease in the activities of serum enzymes like alkaline phosphatase, acid phosphatase and HMGCoA reductase activity in the liver was observed. However, treatment of rats with the extracts as well as standard antidiabetic drugs increased liver hexakinase activity and serum LDH activity.

Diagnosis of hepatitis C virus infection by ELISA, RIBA and RT-PCR: a comparative evaluation

OBJECTIVES

To evaluate the efficacy of second-generation ELISA (ELISA-2), third-generation ELISA (ELISA-3) and third-generation recombinant immunoblot assay (RIBA 3.0) for detection of antibodies to hepatitis C virus (anti-HCV) in comparison with reverse transcriptase-polymerase chain reaction (RT-PCR) to detect HCV RNA for the diagnosis of hepatitis C.

METHODS

Sera of 108 patients with chronic liver disease (CLD) were analyzed by ELISA-2, ELISA-3, RIBA 3.0 and RT-PCR in the first part of the study; in the second part, sera of 105 patients with non-chronic liver disease were evaluated with ELISA-3, RIBA 3.0 and RT-PCR.

RESULTS

In the CLD group, anti-HCV was positive in 4.6%, 14.8% and 16.6% by ELISA-2, ELISA-3 and RIBA 3.0, respectively. Among these anti-HCV positive cases, HCV RNA was positive in 100%, 58.9% and 64%, respectively. ELISA-2 did not give false-positive results, but missed substantial number of anti-HCV positive cases (p < 0.001). In the second group, anti-HCV was positive in 76.3% by ELISA-3 and 68.6% by RIBA 3.0 (p:ns). HCV-RNA was positive in 88.7% of ELISA- and RIBA-positive cases; in 60% of ELISA-positive, RIBA-indeterminate cases; and in 46.4% of ELISA-negative, RIBA-negative cases.

CONCLUSIONS

ELISA-2 is not a suitable assay for routine screening. ELISA-3 was at par with RIBA 3.0 and it can be recommended for routine screening for anti-HCV. RT-PCR for HCV is of value in detecting early viremic, anti-HCV negative cases; this may be of importance in the treatment of hepatitis C.

Inhibition of invasion in vitro and stimulation of aggregation by 13-cis retinoic acid correlates with the clustering of N-CAM in c-Ha-ras transformed glial cells

Invasion distinguishes malignant from benign primary brain tumors. The molecular mechanisms which permit malignant brain tumor cells to escape from the primary tumor mass and by which they can migrate through normal brain tissue are largely unknown. 13-cis retinoic acid (cRA) can induce morphological, biochemical and functional differentiation characteristics in various malignant tumors. Upon treatment of diffusely invasive hamster glial cells (CxT24neo3) with 30 mu M cRA, we found a significant reduction in cell proliferation in monolayer and spheroid cultures. cRA also inhibits invasion of CxT24neo3 through a reconstituted basement membrane (Matrigel(R)) in a dose dependent manner. Homotypic cell-cell adhesion, on the contrary, is stimulated in the absence of extracellular Ca++ by either treatment or pretreatment of CxT24neo3 with cRA. These phenotypic changes correlate with the induction of the clustering of the neural cell adhesion molecule: N-CAM at sites of cell-cell contact. This phenomenon is observed following immunohistochemical staining for N-CAM of CxT24neo3 cells that were treated with cRA in monolayer cultures. The relationship between reduction of proliferation and invasion in vitro and the increased homotypic cell-cell adhesion with clustering of N-CAM implicates N-CAM as a molecular effector molecule for reduction of malignancy by cRA.