SARS-CoV-2 variants infectivity prediction and therapeutic peptide design using computational approaches

The outbreak of severe acute respiratory coronavirus 2 (SARS-CoV-2) has created a public health emergency globally. SARS-CoV-2 enters the human cell through the binding of the spike protein to human angiotensin converting enzyme 2 (ACE2) receptor. Significant changes have been reported in the mutational landscape of SARS-CoV-2 in the receptor binding domain (RBD) of S protein, subsequent to evolution of the pandemic. The present study examines the correlation between the binding affinity of mutated S-proteins and the rate of viral infectivity. For this, the binding affinity of SARS-CoV and variants of SARS-CoV-2 towards ACE2 was computationally determined. Subsequently, the RBD mutations were classified on the basis of the number of strains identified with respect to each mutation and the resulting variation in the binding affinity was computationally examined. The molecular docking studies indicated a significant correlation between the Z-Rank score of mutated S proteins and the rate of infectivity, suitable for predicting SARS-CoV-2 infectivity. Accordingly, a 30-mer peptide was designed and the inhibitory properties were computationally analyzed. Single amino acid-wise mutation was performed subsequently to identify the peptide with the highest binding affinity. Molecular dynamics and free energy calculations were then performed to examine the stability of the peptide-protein complexes. Additionally, selected peptides were synthesized and screened using a colorimetric assay. Together, this study developed a model to predict the rate of infectivity of SARS-CoV-2 variants and propose a potential peptide that can be used as an inhibitor for the viral entry to human.Communicated by Ramaswamy H. Sarma.

Impact of Neoadjuvant Concurrent Chemoradiation (NACCRT) on Operability and Survival in Locally Advanced Inoperable Breast Cancer

PURPOSE/OBJECTIVE(S)

Inoperable locally advanced breast cancers (LABC) are treated with neoadjuvant chemotherapy (NACT). However, many patients remain inoperable after NACT due to an inadequate response. We, therefore, investigated the role of neoadjuvant concurrent chemoradiation (NACCRT) in this setting.

MATERIALS/METHODS

Patients with inoperable Stage III LABC were prospectively recruited in the study between May 2017 and December 2021. NACT consisted of 4 cycles of q3weekly Adriamycin (60 mg/m2) and Cyclophosphamide (600mg/m2), and 4 cycles of q3weekly Paclitaxel (175 mg/m2). Concurrent radiotherapy with 6 MV X-rays was given using a 3D conformal technique to a total dose of 46 Gy (2 Gy/fraction, 5 days/week) to the involved breast, axilla, supraclavicular fossa, and internal mammary chain (upper 3 intercostal spaces) along with the first two cycles of paclitaxel. A 0.5 cm bolus was used to boost the skin till the appearance of hyperpigmentation. All patients were assessed for surgery after the completion of the planned neoadjuvant treatment. Adjuvant treatments were given based on the receptor status. The impact of neoadjuvant CTRT on the pathological complete response (pCR), operability, and survival was analyzed. Event-free survival (EFS) and Overall Survival (OS) were analyzed using the Kaplan-Meier method.

RESULTS

The study enrolled 202 female patients with a median age of 52 years, with 23.7% having IIIA, 65.3% IIIB, and 10.8% having IIIC disease. Hormone-receptor (HR) positive disease was observed in 90/202 (44.6%) patients, triple-negative (TNBC) in 50/202 (24.8%) and Her2/neu positive in 62/202 (30.7%) patients. Modified radical mastectomy was performed in 88.1% of patients, with 8.5% remaining inoperable and 3.4% declining surgery due to clinical complete response (cCR). Among the patients who underwent MRM, 65/178 (32.2%) patients had a pCR. pCR was observed in 13/81 (16%) with HR-positive disease, 21/46 (45.6%) with TNBC, and 31/51 (60.7%) patients with Her2/neu-positive disease. Grade 3 skin reactions were observed in 39/202 (19.3%). Postoperative wound morbidity requiring hospitalization was observed in 19/178 (10.6%) patients. The median follow-up was 42 months, with 4-year EFS and OS of 63.8% and 71.5%, respectively. Six out of 7 patients who were in cCR and declined surgery are alive and remain in cCR. On subgroup analysis of Her 2 positive patients, pCR was significantly associated with improved EFS and OS (89.8% vs 33.3%, p = 0.001 and 89.1% vs 44.4%, p = 0.001 respectively).

CONCLUSION

Our study demonstrates the feasibility and efficacy of NACCRT in improving operability, pCR rates and survival outcomes in patients with inoperable LABC. The results suggest that NACCRT can be considered for use in clinical practice with careful patient selection. These findings contribute to the ongoing efforts to optimize treatment for this patient population and warrant further investigation in larger, randomized trials.

POS0400 METABOLIC CHANGES INDUCED BY ANTI-MALONDIALDEHYDE/MALINDIALDEHYDE-ACETALDEHYDE ANTIBODIES PROMOTE OSTEOCLAST DEVELOPMENT

Background:

Malondialdehyde (MDA) is a highly reactive compound generated during lipid-peroxidation in conditions associated with oxidative stress. MDA can irreversibly modify proteins (e.g. lysine, arginine and histidine residues). In addition, acetaldehyde can further react with MDA adducts to form malondialdehyde-acetaldehyde (MAA) modification. Such protein modifications can lead to immunogenic neo-epitopes that are recognized by autoantibodies. In fact, anti-MDA/MAA IgG antibodies are significantly increased in the serum of patients with autoimmune diseases, such as rheumatoid arthritis (RA) (1). Interestingly, anti-MDA/MAA antibodies have been shown to promote osteoclast (OC) differentiation in vitro suggesting a potential role for these autoantibodies in bone damage associated with RA (1).

Objectives:

Little is known about the molecular mechanisms activated by autoantibodies in RA. Here, we elucidate the pathways specifically triggered by anti-MDA/MAA autoantibodies in developing osteoclasts.

Methods:

Recombinant human monoclonal anti-MDA/MAA antibodies, which were previously cloned from single synovial B cells of RA patients, were added to different OC assays. OCs were generated from monocyte-derived macrophages in the presence of the cytokines RANK-L and M-CSF. OC development was monitored by light microscopy following tartrate-resistant acid phosphatase staining and by erosion assays using calcium phosphate-coated plates. Bone morphometrics were studied in anti-MDA/MAA-injected mice using X-ray microscopy. Cellular metabolism was analyzed by mass spectrometry, Seahorse XF Analyzer and a colorimetric L-Lactate assay.

Results:

Anti-MDA/MAA antibodies induced a robust OC differentiation in vitro and bone loss in vivo. The anti-MDA/MAA antibodies acted on developing OCs by increasing glycolysis via an Fcγ receptor I-mediated pathway and the upregulation of the transcription factors HIF-1α, Myc and CHREBP. Such regulation of cellular metabolism was exclusively observed in the presence of the osteoclastogenic anti-MDA/MAA clones, whereas other RA-associated autoantibodies (anti-MDA/MAA or anti-citrullinated protein antibodies) had no effect on metabolism. The anti-MDA/MAA treatment induced a shift in the tricarboxylic acid (TCA) cycle activity in developing OCs, leading to the accumulation of citrate and aconitate.

Conclusion:

We described a novel type of autoantibody-induced pathway in RA, which might contribute to increased OC activation and a consequent bone loss. Anti-MDA/MAA antibodies promoted osteoclast development by increasing glycolysis and by modulating the TCA cycle through a signaling pathway that included Fcγ receptor I and a network of transcription factors acting on glycolysis. A TCA cycle bias towards citrate production suggests that the anti-MDA/MAA antibodies might stimulate OCs via increasing lipid biosynthesis in the cells.

References:

[1]Grönwall C. et al. J. Autoimmunity 84 (2017): 29-45.

Acknowledgements:

This Project has received funding from FOREUM, Foundation for Research in Rheumatology, from the European Research Council (ERC) grant agreement CoG 2017 - 7722209_PREVENT RA, the EU/EFPIA Innovative Medicine Initiative grant agreement 777357_RTCure, the Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse and Knut and Alice Wallenberg Foundation.

Disclosure of Interests:

Koji Sakuraba: None declared, Akilan Krishnamurthy: None declared, Alexandra Circiumaru: None declared, Vijay Joshua: None declared, Heidi Wähämaa: None declared, Marianne Engström: None declared, Meng Sun: None declared, Xiaowei Zheng: None declared, Cheng Xu: None declared, Khaled Amara: None declared, Vivianne Malmström Grant/research support from: collaboration with Pfizer, unrelated to the abstract, Sergiu-Bogdan Catrina: None declared, Caroline Grönwall: None declared, Bence Réthi: None declared, Anca Catrina Grant/research support from: collaboration with BMS and Pfizer, unrelated to the present abstract

Potential protease inhibitors and their combinations to block SARS-CoV-2

COVID-19, which has emerged recently as a pandemic viral infection caused by SARS-coronavirus 2 has spread rapidly around the world, creating a public health emergency. The current situation demands an effective therapeutic strategy to control the disease using drugs that are approved, or by inventing new ones. The present study examines the possible repurposing of existing anti-viral protease inhibitor drugs. For this, the structural features of the viral spike protein, the substrate for host cell protease and main protease of the available SARS CoV-2 isolates were established by comparing with related viruses for which antiviral drugs are effective. The results showed 97% sequence similarity among SARS and SARS-CoV-2 main protease and has same cleavage site positions and ACE2 receptor binding region as in the SARS–CoV spike protein. Though both are N-glycosylated, unlike SARS-CoV, human SARS-CoV-2 S-protein was O-glycosylated as well. Molecular docking studies were done to explore the role of FDA approved protease inhibitors to control SARS-CoV-2 replication. The results indicated that, Ritonavir has the highest potency to block SARS-CoV-2 main protease and human TMPRSS2, a host cell factor that aids viral infection. Other drugs such as Indinavir and Atazanavir also showed favourable binding with Cathepsin B/L that helped viral fusion with the host cell membrane. Further molecular dynamics simulation and MM-PBSA binding free energy calculations confirmed the stability of protein-drug complexes. These results suggest that protease inhibitors particularly Ritonavir, either alone or in combination with other drugs such as Atazanavir, have the potential to treat COVID 19.

Communicated by Ramaswamy H. Sarma

OP0326 ACPA-INDUCED PAIN-BEHAVIOR, BONE LOSS AND TENDON INFLAMMATION IN MICE: A NOVEL MODEL FOR THE PRE-DISEASE PHASES OF ACPA-POSITIVE RHEUMATOID ARTHRITIS

Background:

In rheumatoid arthritis (RA), anti-citrullinated protein antibodies (ACPAs) are associated with bone loss and pain. Recently, tenosynovitis has been suggested as a predicting factor for arthritis progression in individuals at-risk for RA.

Objectives:

We aimed to investigate if transfer of human ACPAs into mice could induce tenosynovitis and/or subclinical inflammation.

Methods:

Monoclonal ACPA (1325:04C03 and 1325:01B09) and control (1362:01E02) antibodies (mAbs) were generated from synovial plasma or memory B cells of RA patients. 2mg of combination of monoclonal ACPAs or control antibody were injected in BALB/c female mice (age 12-16 weeks) (n= 9). Pain-like behavior was monitored by measuring mechanical hypersensitivity using von Frey filaments every 3 days and estimation by up-down Dixon method. Bone morphometrics was analyzed by micro-CT. Using specially designed mobilization casts, dedicated mouse MRI coils, and gadolinium enhanced contrast medium, the hind limbs of these mice were scanned in a 9.4 T scanner and resulting T1-weighted images were evaluated for signs of soft tissue joint inflammation. The MRI images were scored for the presence of joint involvement and tendon inflammatory changes by 3 readers in a blinded manner.

Figure 1.

NAPA performed on healthy donor mo-DCs incubated with native, PAD2-citrullinated, and PAD4-citrullinated fibrinogen. Alpha, beta, and gamma chains of fibrinogen are shown separately. Each colored line represents a unique peptide. Nested peptides with a common core motif are shown in the same color. Grey bar denotes peptides with identical core motif between samples.

Results:

ACPAs (1325:04C03 and 1325:01B09) induced pain-like behavior (lasting for at least 4 weeks) and reduction of the trabecular and cortical bone thickness in the hind limbs as compared to control monoclonal antibodies (p<0.05). While no macroscopic or MRI signs of synovial inflammation were detected, MRI subclinical inflammation of the tendon sheaths was present in mice injected with ACPAs, but not in those injected with control mAb. Semi-quantitative scoring of the inflammatory tendon changes showed significant higher values in mice injected with ACPA (median of 1, range 0 to 2) than those injected with control mAb (median of 0, range 0 to 1).

Conclusion:

We show that ACPA induces pain-like behavior, bone loss and tendon sheath inflammation in mice, a model that mimics the preclinical state of ACPA positive RA.

References:

[1]Harre, U. et al. J Clin Invest (2012)

[2]Krishnamurthy, A. et al. Ann Rheum Dis (2016, 2019), JI 2019

[3]Wigerblad, G. et al. Ann Rheum Dis (2016, 2019)

[4]KleyerA, Seminars in Arthritis and Rheumatism (2016)

Disclosure of Interests:

Akilan Krishnamurthy: None declared, Yogan Kisten: None declared, Alexandra Circiumaru: None declared, Koji Sakurabas: None declared, Patrik Jarvolli: None declared, Juan Jimenez Jimenez Andrade: None declared, Peter Damberg: None declared, Heidi Wähämaa: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica, Lars Klareskog: None declared, Camilla Svensson: None declared, Bence Réthi: None declared, Anca Catrina: None declared

SAT0017 METABOLIC CHANGES INDUCED BY ANTI-MALONDIALDEHYDE/MALINDIALDEHYDE-ACETALDEHYDE ANTIBODIES PROMOTE OSTEOCLAST DEVELOPMENT

Background:

Malondialdehyde (MDA) is a highly reactive compound produced by lipid-peroxidation in situations associated with oxidative stress. MDA can irreversibly modify proteins residues such as lysine, arginine and histidine. In addition, MDA adducts can further react with acetaldehyde to generate malondialdehyde-acetaldehyde (MAA) modifications. Such modifications can give rise to immunogenic neo-epitopes that are recognized by autoantibodies. In fact, anti-MDA/MAA IgG antibodies are significantly increased in the serum of patients with autoimmune diseases, such as rheumatoid arthritis (RA) (1) and systemic lupus erythematosus (2). Recently, we have shown that anti-MDA/MAA IgG antibodies are able to promote osteoclast (OC) differentiationin vitro(1).

Objectives:

To investigate the molecular mechanisms triggered by anti-MDA/MAA autoantibodies during osteoclastogenesis.

Methods:

OCs were generated from monocyte-derived macrophages in the presence of the cytokines RANK-L and M-CSF. The development of OCs was monitored by light microscopy following tartrate-resistant acid phosphatase (TRAP) staining and erosion area on synthetic calcium phosphate-coated plates. Three different recombinant human monoclonal anti-MDA/MAA antibodies, cloned from single synovial B cells of RA patients, control antibodies and Fab fragments of the antibodies were added to OC cultures. Glycolysis was inhibited by 2-deoxyglucose, and Fc-gamma receptor I or II by anti-CD64 or anti-CD16 neutralizing antibodies. IL-8 levels were measured by enzyme linked immunosorbent assay. Cellular metabolism was monitored using Seahorse XF Analyzer (extracellular acidification rate and oxygen consumption) and a colorimetric L-Lactate assay.

Results:

Lactic acid production correlated with the osteoclastogenetic effect of some but not all anti-MDA/MAA antibodies on OCs (R=0.4758, p=0.0252) suggesting an antibody-mediated regulation of glycolysis. Further, extracellular acidification (ECAR) and oxygen consumption (OCR) rate of the developing OCs were increased by the osteoclastogenic anti-MDA/MAA clones (maximum increase of 54% for the ECAR and 78% for the OCR by clone 146+:01G07, and maximum increase of 28% for the ECAR and 39% for the OCR by clone 1103:01H05), but not by the non-osteoclastogenetic anti-MDA/MAA clones or control antibodies. The glycolysis inhibitor 2-deoxyglucose completely abolished the osteoclastogenetic effect of the anti-MDA/MAA clones at drug concentrations that did not influenced baseline OC development. Fab2 fragments of the osteocalstogenetic anti-MDA/MAA clones had no effect on OC development and metabolism. In accordance with this, Fc-gamma receptor I neutralizing antibodies completely abolished the osteocalstogenetic effect of the anti-MDA/MAA clones. The osteoclastogenetic effect of the anti-MDA/MAA antibodies was independent of IL-8 production. In contrast to anti MDA/MAA antibodies, ACPA-mediated osteoclastogenesis was independent of glycolysis and Fc-gamma receptors but dependent on IL-8.

Conclusion:

Our results describe a novel glycolysis-dependent mechanism by which anti-MDA/MAA antibodies promote osteoclast development that is different from the one previously described for ACPA.

References:

[1] C. Grönwall et al. Journal of Autoimmunity 84 (2017) 29-45.

[2] C. Wang et al. Arthritis and Rheumatism 62 (2010) 2064-2072

Disclosure of Interests:

Koji Sakuraba: None declared, Akilan Krishnamurthy: None declared, Alexandra Circiumaru: None declared, Meng Sun: None declared, Vijay Joshua: None declared, Marianne Engström: None declared, Xiaowei Zheng: None declared, Cheng Xu: None declared, Khaled Amara: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica, Sergiu-Bogdan Catrina: None declared, Caroline Grönwall: None declared, Bence Réthi: None declared, Anca Catrina: None declared

FRI0005 DIVERSITY OF ANTI-CITRULLINATED PROTEIN ANTIBODY COMPOSITIONS INFLUENCE SYNOVIAL FIBROBLAST REACTIVITY

Background:

Anti-citrullinated protein antibodies (ACPAs) play an important role in rheumatoid arthritis (RA) pathogenesis. We hypothesized that the effect of these antibodies is mediated by their binding to synovial fibroblasts and inducing an increased mobility of fibroblasts1.

Objectives:

In our study, we analyzed and compared fibroblast modulation by ACPA pools obtained from different patients or by a set of monoclonal ACPAs with different fine specificity that were obtained from different tissue sites.

Methods:

Synovial fibroblasts were isolated from RA patients synovial tissue biopsies. Individual polyclonal ACPA and control IgGs were purified from sera of four ACPA-positive RA patients by affinity purification on protein G and CCP-2 columns. Monoclonal antibodies were derived from memory B cell isolated from blood2, synovial fluid or bronchoalveolar lavage of RA patients. Whole antibodies and F(ab’)2 fragments were tested in fibroblast migration using IncuCyte live-cell analysis. Blocking experiments were performed with soluble citrullinated proteins in SF migration. Cross-reactivity of the antibodies to citrullinated and acetylated epitopes was tested using PAD inhibitors (Cl-amidine and GSK199), histone acetyltransferases (anacardic acid) and deacetylases (trichostatin A). Binding patterns of monoclonal ACPAs, both whole and F(ab’)2 fragments were analyzed in synovial biopsies obtained from both healthy donors and RA patients.

Results:

Three out of four tested individual ACPA were able to promote fibroblast migration. Five out of nine tested monoclonal ACPAs stimulated fibroblast migration. One of these antibodies, clone 1325:01B09 is characterized by cross-reactivity to citrullinated, homocitrullinated and acetylated targets. The effect of 1325:01B09 on fibroblast migration was completely abolished by Cl-amidine or by pre-incubating the antibody with citrullinated fibrinogen or histone but not citrullinated enolase or vimentin. Despite the cross-reactivity to acetylated epitopes, neither anacardic acid nor trichostatin A could modulate the 1325:01B09 effect on fibroblast migration. F(ab’)2 fragments of this antibody stimulated fibroblast migration and labelled podoplanin-positive fibroblasts in inflamed RA synovium similarly to the intact antibody, indicating an Fc-independent effect.

Conclusion:

The effect on fibroblast mobility was likely to be mediated by binding to citrullinated epitopes but not through Fc receptors. Detection of fibroblast modulating ACPAs in majority of RA patients indicated that fibroblasts might be key cellular targets in disease pathogenesis, although individual variability might exist in the composition of ACPA cellular targets.

References:

[1]Sun M, Rethi B, Krishnamurthy A, et al. Anticitrullinated protein antibodies facilitate migration of synovial tissue-derived fibroblasts. Ann Rheum Dis 2019;78(12):1621-31. doi: 10.1136/annrheumdis-2018-214967 [published Online First: 2019/09/05]

[2]Amara K, Lena Israelsson, Ragnhild Stålesen, et al. A Refined Protocol for Identifying Citrulline-specific Monoclonal Antibodies from Single Human B Cells from Rheumatoid Arthritis Patient Material. Bio-protocol 2019;9(16)

Disclosure of Interests:

Meng Sun: None declared, Bence Réthi: None declared, Akilan Krishnamurthy: None declared, Vijay Joshua: None declared, Alexandra Circiumaru: None declared, Marianne Engström: None declared, Caroline Grönwall: None declared, Vivianne Malmström Grant/research support from: VM has had research grants from Janssen Pharmaceutica, Khaled Amara: None declared, Lars Klareskog: None declared, Heidi Wähämaa: None declared, Anca Catrina: None declared

Advanced buffer materials for indoor air CO2 control in commercial buildings

In this study, we evaluated solid sorbents for their ability to passively control indoor CO₂ concentration in buildings or rooms with cyclic occupancy (eg, offices, bedrooms). Silica supported amines were identified as suitable candidates and systematically evaluated in the removal of CO₂ from indoor air by equilibrium and dynamic techniques. In particular, sorbents with various amine loadings were synthesized using tetraethylenepentamine (TEPA), poly(ethyleneimine) (PEI) and a silane coupling agent 3-aminopropyltriethoxysilane (APS). TGA analysis indicates that TEPA impregnated silica not only displays a relatively high adsorption capacity when exposed to ppm level CO₂ concentrations, but also is capable of desorbing the majority of CO₂ by air flow (eg, by concentration gradient). In 10 L flow-through chamber experiments, TEPA-based sorbents reduced outlet CO₂ by up to 5% at 50% RH and up to 93% of CO₂ adsorbed over 8 hours was desorbed within 16 hours. In 8 m³ flow-through chamber experiments, 18 g of the sorbent powder spread over a 2 m² area removed approximately 8% of CO₂ injected. By extrapolating these results to real buildings, we estimate that meaningful reductions in the CO₂ can be achieved, which may help reduce energy requirements for ventilation and/or improve air quality.

Atezolizumab: A novel PD-L1 inhibitor in cancer therapy with a focus in bladder and non-small cell lung cancers

In recent years, immunotherapy has come to the forefront as a major development in cancer treatment. Evasion of the immune system by tumor cells has been identified as one of the hallmarks of cancer and multiple therapies have been developed to counter this process. Programmed cell death 1 ligand 1 (PD-L1), a ligand to programmed cell death protein 1 (PD-1), is expressed by many cancer cells and the binding of PD-L1 to PD-1 results in the suppression of T-cell-mediated immune response against cancer cells. Atezolizumab is a monoclonal antibody that binds to PD-L1 and blocks its interaction with PD-1, thereby enhancing T-cell activity against tumor cells. Atezolizumab has been shown to be well tolerated with no dose-limiting toxicities in phase I trials. Atezolizumab was approved by the U.S. Food and Drug Administration in 2016 for the treatment of platinum-resistant metastatic non-small cell lung cancer (NSCLC) and urothelial cancer based on phase II and preliminary phase III studies that have shown significant improvement in objective response rate and median overall survival. There are 117 ongoing clinical trials of atezolizumab currently. Given its efficacy in NSCLC and urothelial carcinoma, atezolizumab holds much potential in the future of cancer therapeutics.

The increasing challenge of never smokers with adenocarcinoma lung: Need to look beyond tobacco exposure

BACKGROUND

Lung cancer continues to remain as one of the leading causes of morbidity and mortality worldwide, despite the decreasing trends in smoking prevalence worldwide. An earlier study from the authors' institute reported the increasing trends of "Nonsmoking associated lung cancers."

MATERIALS AND METHODS

All consecutive histologically confirmed patients with lung cancer who presented to the outpatient department over a year (November 2014-October 2015) were included in this current prospective study.

RESULTS

Seven hundred and thirteen patients presented with clinicoradiologically suspicious findings of lung cancer in the said period. A pathological confirmation of lung cancer could be ascertained in 495 patients, and this cohort was further analyzed. The mean age of presentation was 57.76 years; the male to female ratio was approximately 2.5:1. Interestingly, 55.35% of the patients were nonsmokers. Adenocarcinoma (63%) was the predominant histology. Never smokers, both among men (P = 0.02) and women (P = 0.001), presented more frequently with adenocarcinoma histology. Further, 84.9% (45/53) of rural and 76.1% (19/25) of urban women who were never smokers reported exposure to indoor air pollution (secondhand smoke/fuel used for cooking purposes) which was significantly associated with adenocarcinoma histology.

CONCLUSION

Our study confirmed our initial observation of the changing epidemiology of lung cancer in the Indian subcontinent, paralleling the global trends of rise in adenocarcinoma. Lung cancer in never smokers outnumbering that among smokers was another interesting observation. The take-home message for both the clinicians as well as the policymakers is to study factors beyond tobacco exposure to understand the direction of the current lung cancer epidemic.

Chemotherapy delivery for resected colorectal cancer liver metastases: Management and outcomes in routine clinical practice

BACKGROUND

International guidelines recommend peri-operative chemotherapy for patients with resectable colorectal cancer liver metastases (CRCLM). Chemotherapy delivery in routine practice is not well described.

METHODS

All cases of CRC who underwent resection of LM in 2002-2009 were identified using the population-based Ontario Cancer Registry. Electronic treatment records identified chemotherapy delivered within 16 weeks before or after hepatectomy. All pathology reports were reviewed to describe extent of LM. Modified Poisson regression was used to evaluate factors associated with chemotherapy delivery. Cox proportional hazards model and propensity score analysis were used to explore the association between post-operative chemotherapy and cancer-specific (CSS) and overall (OS) survival.

RESULTS

We identified 1310 patients. Sixty-two percent of cases (815/1310) received peri-operative chemotherapy; 25% (200/815) pre-operative, 45% (366/815) post-operative, and 31% (249/815) pre- and post-operative. Utilization of chemotherapy increased over time from 51% in 2002 (57/112) to 73% in 2009 (157/216, p < 0.001). Fifty-four percent of patients received FOLFOX, 41% FOLFIRI, and 10% 5-FU monotherapy. Factors that were independently associated with greater utilization of post-operative chemotherapy included younger age (p < 0.001), female sex (p = 0.050), shorter disease-free interval (p = 0.006), and no prior adjuvant chemotherapy (p < 0.001). Utilization of chemotherapy varied substantially across geographic regions (from 24% to 71%, p = 0.001). Post-operative chemotherapy was associated with improved CSS (HR 0.58, 95%CI 0.44-0.76) and OS (HR 0.49, 95%CI 0.38-0.61); results were consistent in propensity score analysis.

CONCLUSION

Utilization of chemotherapy for resected CRCLM in routine practice has evolved with emerging evidence. Post-operative chemotherapy is associated with improved survival in the general population.

Etanercept decreases synovial expression of tumour necrosis factor-α and lymphotoxin-α in rheumatoid arthritis

OBJECTIVES

Etanercept is an effective tumour necrosis factor (TNF)-α inhibitor drug with the unique ability to block not only TNF-α but also lymphotoxin (LT)-α, at least in vitro. We aimed to investigate the in vivo effect of etanercept on synovial expression of TNF-α and LT-α.

METHOD

Synovial biopsies from 12 rheumatoid arthritis (RA) patients started on etanercept and 11 RA patients started on infliximab were obtained at baseline and 8 weeks after treatment initiation. Synovial expression of TNF-α and LT-α was evaluated by immunohistochemistry followed by computer-assisted image analysis. Differences between paired samples were analysed by the Wilcoxon test and between groups by the Mann-Whitney test. A p-value < 0.05 was considered statistically significant.

RESULTS

Six out of the 12 of the patients started on etanercept achieved an American College of Rheumatology (ACR)50 response. Macroscopic evaluation of the joints during arthroscopy revealed a significant decrease of local inflammation mainly in good ACR50 responders. Synovial expression of both LT-α and TNF-α decreased but the differences did not reach statistical significance at a group level. By contrast, a significant decrease in both LT-α and TNF-α was observed when only good ACR50 responders were analysed. Despite higher levels of baseline synovial TNF-α in the good responders, neither baseline LT-α nor TNF-α could predict clinical response after 8 weeks. A decreasing trend of the synovial levels of LT-α was also observed in good responders to infliximab, but the difference did not reach statistical significance.

CONCLUSIONS

Etanercept treatment modulates the synovial expression of both TNF-α and LT-α in vivo, a mechanism that might partly explain its clinical efficacy in RA.

Bilateral arterial variation in the upper extremity--an anatomical case report

We report a case of bilateral arterial variation in the upper extremities of a male cadaver. In the left upper extremity, it was observed that the ulnar artery was arising from axillary artery. This ulnar artery was superficial throughout its course at the medial aspect of the arm and forearm. It was highly tortuous and did not have any branches either in the arm or forearm. It ended as the superficial palmar arch in the palm. However the brachial artery entered the cubital fossa and divided into radial and common interosseus arteries. In contrast, the right upper extremity was having normal brachial artery which was terminated into the ulnar and radial arteries at the cubital fossa. However, there was an accessory brachial artery present at the arm and ended at the cubital fossa. We believe that these anatomical variations are because of abnormal developmental vascular pattern in the region. In clinical practice, accurate knowledge of the arterial variations of upper extremity is of considerable importance in case of reparative surgeries and fracture management. They are of interest to the vascular and plastic surgeons.

Incomplete discoid lateral meniscus: a case report

The variations of lateral meniscus include pathologic entities which vary in size, shape and attachment. In this manuscript, we report a case of discoid lateral meniscus which was observed in an embalmed fetal cadaver. It was an incomplete variety of the discoid meniscus and observed on the right side knee. The clinical implication of this discoid meniscus has been emphasized along with the review of literature. The morphological and embryologic details of the discoid lateral menisci are discussed.

Bone morphometry

OBJECTIVES

To compare anatomical measurements with that of radiological measurements.

BACKGROUND

The radiological measurements are commonly used in clinical practice. It is well known that the anatomical measurements are more accurate than radiological. The comparison of anatomicoradiological measurements is not reported hitherto.

METHODS

One human adult cadaveric femur bone was used for the present study. It was measured both anatomically and radiologically.

RESULTS

In digital X- ray measurements, the length from the upper lip of fovea capitis to the most prominent part of greater trochanter was 87.2 mms, from the upper most part of greater trochanter to the isthmus it was 147.9 mms, mediolateral width of medullary cavity at the isthmus was 8.9 mms, the mediolateral width at the distal root of lesser trochanter was 18.5 mms, anteroposterior width of medullary cavity at the isthmus was 11.5 mms, the anteroposterior width at the distal root of lesser trochanter was 16.8 mms. The same measurements were 91.2 mms, 154.6 mms, 11.8 mms, 19.7 mms, 11.9 mms and 18.5 mms when taken anatomically using the digital vernier caliper.

CONCLUSION

The present study showed that in all the parameters measured the radiological values were slightly lesser than the anatomical values. Considering the variations in the values, the implants can be designed for a particular case in orthopedic surgery. We believe that this study adds an important reference in the scientific literature (Tab. 1, Fig. 2, Ref. 5).

Clinically oriented morphometric study of medial and lateral menisci of the knee joint in adult cadavers

PURPOSE

The objective was to analyze the peripheral and inner border lengths of the medial and lateral menisci and the distance between anterior and posterior horns.

MATERIALS AND METHODS

The menisci from 23 adult knee joints (46 menisci) of the formalin fixed cadaver lower limbs were used. The peripheral and inner borer lengths of the menisci were measured with a non elastic cotton thread and the distance between the horns were measured with the vernier caliper of 0.02 mm accuracy.

RESULTS

The mean peripheral lengths of the medial and lateral menisci were 99.06 +/- 11.21 and 90.25 +/- 9.36 mm respectively. The inner border lengths for the same were determined as 55.44 +/- 8.37 and 50.63 +/- 5.33 mm respectively. The distances between the anterior and posterior horns were 24.13 +/- 4.19 and 11.31 +/- 3.86 mm for the same. The peripheral length and inter horn distance of the medial meniscus was more than the lateral, the statistically significance was observed (*p<0.05). The other parameters obtained were statistically not significant.

CONCLUSION

The present study had determined some important anatomical data which may be of importance to the orthopaedic literature. The findings are also enlightening for the anthropologists and clinical anatomists.

Morphometric analysis of clavicle in nepalese population

BACKGROUND

Determining the sex of deceased is easy when a complete skeleton is available for examination. On the whole, the bones are heavier, larger and markings of muscular attachments are more pronounced in the male than in the female.

OBJECTIVE

The purpose of this study was attempted to evolve an easily applied formula to enable the assessment of sex in an unknown clavicles and to know about comparative differences between the right and left clavicles, from certain metrical parameters.

METHODS

The study was an observational, cross-sectional and descriptive in nature. The present study was conducted on 257 adult clavicles out of which, 135 were of the right side and 122 of left side. The maximum length of the clavicle (in mm) was taken.

RESULTS

The length of the right clavicles varies from 108 mm to 178 mm with an average of 143.21 mm ± 11.13 mm S.D. The length of the left clavicles varies from 111 mm to 181 mm with an average 145.53 mm ± 11.04 mm S.D. It has been observed that the left clavicle was longer than the right clavicle by 2.32 mm. There was no such single character which can determine the sex of all clavicles. Depending on the length alone, the sex can be decided in 13.33% male and 4.44% female right clavicles and 16.39% male and 9.83% female bones if the left clavicle is considered.

CONCLUSION

The left clavicle was longer than the right clavicle. The determination of sex from the clavicle has a great medico legal significance to the toxicologists. It also helps the anthropologists in their study of evolution of mankind and migration of races.

Foramina on the zygomatic bone: its clinical significance

AIM

To study the anatomy of zygomatico-orbital, zygomatico-facial and zygomatico temporal foramina in south Indian population.

MATERIALS AND METHODS

50 dry adult skulls of south Indian origin were studied. The number of ZO, ZF and ZT were recorded on each side. The distances of these foramina to the nearest palpable bony points, infero-lateral angle of the orbit and infra-orbital foramen were measured using Vernier's calipers.

RESULTS

Variable number of ZO and ZF foramina, ranging from 0 to 4 was seen. Single ZO foramen in 56% and 44%, double in 6% and 12%, absent in 38% and 44% on right and left sides were seen. Distance of ZO foramen from inferolateral angle of orbit was 9+2.51 mm and 7.8+1.74 mm on right and left side respectively. The mean distance from infraorbital foramen was 29.93+2.76 mm and 30.19+ 3.52 mm on right and left side respectively. Single ZF foramen in 40% and 42%, double in 10% and 8%, 3 in 4% on right side and 4 in 2% on left sides were seen. In the remaining 46% and 48% of bones, the ZF foramen was absent. Mean distance from inferolateral angle of orbit was 8.05+2.68 and 9.15+2.11 mm respectively on the right and left side. Mean distance from infraorbital foramen was 25.45+4.35 mm and 25.42+4 mm respectively on right and left side.

CONCLUSION

The location of ZO and ZF foramen can be population specific and knowledge of its location is important during stabilization of zygomatic fractures, in endoscopic subperiosteal facelift.

Bilateral anomaly of rectus capitis posterior muscles in the suboccipital triangle and its clinical implication

Rectus capitis posterior muscles are located in the suboccipital triangle and function in extension and lateral rotation of the head and neck. There are two of these muscles on each side: the rectus capitis posterior major and the rectus capitis posterior minor. In the present case we observed bilateral double rectus capitis posterior major muscle and bilateral absence of rectus capitis posterior minor muscle. The additional rectus capitis posterior major may put more strain to the spine of the axis and mean time the bilateral absence of rectus capitis posterior minor muscles will result in muscular in coordination in the suboccipital region while balancing the head. The present variation should be considered in the aetiology of cervicogenic headache.

Prediction of postoperative pulmonary reserve in lung resection patients

We performed Ventilation/Perfusion scans for patients planned for thoracotomy with resection of the primary or metastatic lung tumors. We predicted the post-operative FEV1 (Forced Expiratory Volume in first second) using Differential Lung Analysis software.

METHODS

34 patients were evaluated with Ventilation/Perfusion (V/Q) scans. Ventilation scan was performed with Tc-99m DTPA Aerosol and Perfusion Scan with Tc99m MAA, on 2 different days. The numbers of counts in anterior and posterior views of V/Q scans were calculated individually. Anterior and posterior arithmetical mean was calculated and post-operative FEV1 was predicted with the use of Differential Lung Analysis software. In most of the patients, the counts in the ventilation scan were lower and they were related to preoperative FEV1. Depending on the volume of lung resection, i.e. Upper, Middle and Lower zones or Total Pneumonectomy, FEV1 was calculated. Whenever FEV1 was >0.8 (L), the patient was taken up for resection (and if there were no other risk factors, such as cardiac complications, chronic obstructive pulmonary diseases, and any other pathological conditions involving the contralateral lung).

RESULTS

Most of the 34 patients were taken up for lung resection based on our FEV1 predictions. In 7 patients, repeat spirometry (i.e. pulmonary function test) was done at varying intervals after surgical procedures and the variation between preoperative FEV(1) and postoperative FEV(1) was only ±15%, at the most.

CONCLUSION

Postoperative FEV(1) based on V/Q scan and pulmonary function tests helped us to proceed with lung resection after assessment of the pulmonary reserve.

Morphology of the medial meniscus of the knee in human fetuses

OBJECTIVES

The objectives were to study the morphology of the medial menisci in human fetal knee joints and to verify the developmental etiology of the discoid meniscus.

MATERIAL AND METHODS

The study was carried out on 106 fetal knee joints and the morphological variants of the shapes of the medial menisci were macroscopically noted and classified.

RESULTS

From our observations, 46.2% of the medial menisci were crescentic shaped, 23.6% were sided V-shaped, 13.2% had sided U-shape, 9.4% of them were sickle shaped, and 7.5% were C-shaped. In 54.71% of the cases, the medial meniscus shape was different on either side knees of the fetuses. No discoid medial menisci were seen.

CONCLUSIONS

The majority of the knees were having crescentic or semi lunar shaped medial menisci and the shape of the medial meniscus was different on right and left side knee joint of the fetuses in more than fifty percent of the cases. The observations favor Kaplan's theory, as there were no discoid medial menisci observed from the fetuses of various gestational ages. Even the youngest fetus (CRL 88 mm, 14 weeks of gestation) exhibited the medial tibial plateau incompletely covered by the menisci, which did not exhibit the discoid shape. The discoid meniscus must be an abnormal finding and is due to abnormal morphogenesis.

Morphometry of A1 segment of the anterior cerebral artery and its clinical importance

BACKGROUND AND AIM

Anterior cerebral artery, one of the terminal branches of the internal carotid artery is an important vessel taking part in the formation of circle of Willis. It supplies a large part of the medial surface of the cerebral hemisphere containing the areas of motor and somatosensory cortices of the lower limb. Aim of this study was the morphometry of A1 segment of the anterior cerebral artery.

MATERIALS AND METHODS

93 formalin fixed brain specimen of either sex and of Indian origin were studied. The mean length, mean external diameter and the anomalies present in A1 segment of the vessel were studied in detail and photographed.

RESULTS

The mean length of A1 segment of the vessel was 14.49+/-0.28 mm and 14.22+/-0.22 mm on right and left side respectively. The mean external diameter of the vessel on right and left side was 2.12+/-0.07 mm and 2.32+/-0.06 mm respectively. Narrowing, aneurysm formation, buttonhole formation and median anterior cerebral artery were the anomalies seen with an occurrence of 15.05%, 5.37%, 3.22% and 12.9%, respectively. The above anomalies did not have any sex or side predilection.

CONCLUSION

Knowledge of morphometry of the vessel will be of use to neurosurgeons while performing the shunt operation, in assessing the feasibility of such operations and in the choice of patients. From this study we infer that the morphometry of anterior cerebral artery varies in different population and that the neurosurgeons operating should have a thorough knowledge of the possible variations.

Anatomy of plantaris muscle: a study in adult Indians

AIM

The plantaris muscle (PM) and its tendon is subject to considerable variation in both the points of origin and of insertion. The present study was carried out to fi nd the different types of origin, insertion and possible variations of the PM in the population of southern costal region of India.

MATERIALS AND METHODS

52 embalmed (Formalin fixed) cadaver lower limbs of 26 males (age ranged 48-79 years, mean age 68 years) were dissected, to study the origin and insertion of PM. Various dimensions (length and width) of plantaris muscle belly and its tendon were also measured.

RESULTS

Three types of origin and equal number of insertion were noticed in the present study. The PM took origin from type I: Lateral Supracondylar ridge, Capsule of Knee joint and Lateral head of gastrocnemius in 73.07% cases; type II: Capsule of Knee joint and Lateral head of gastronemius in 5.76% cases; type III: Lateral Supracondylar ridge , Capsule of Knee joint , Lateral head of gastrocnemius and fibular collateral ligament in 13.46% cases. The plantaris tendon was inserted into type I: to the flexor retinaculum of foot in 28.84% cases; type II: independently to the os calcaneum in 36.53% cases; type III: to the tendocalcaneus at various levels in 26.92% cases. In four lower limbs (7.69%) the plantaris muscle was completely absent. Additionally the length and width of the plantaris muscle and its tendon were measured to know any side difference. There were no statistically significant differences between the measurements of left and right side (p>0.05).

CONCLUSION

Present study will help the surgeons while attempting various surgical procedures in and around the posterior aspect of knee involving plantaris.

Duplication of falx cerebelli, occipital sinus, and internal occipital crest

The incidence of variations of falx cerebelli was studied in 52 adult cadavers of south Indian origin, at Kasturba Medical College Mangalore, after removal of calvaria. In eight (15.4%) cases, we observed duplicated falx cerebelli along with duplicated occipital sinus and internal occipital crest. The length and the distance between each of the falces were measured. The mean length of the right falces cerebelli was 38 mm and the left was 41 mm. The mean distance between these two falces was 20 mm. No marginal sinus was detected. Each of the falces cerebelli had distinct base and apex and possessed a distinct occipital venous sinus on each attached border. These sinuses were noted to drain into the left and right transverse sinus respectively. After detaching the dura mater from inner bony surface of the occipital bone, it was noted that there were two distinct internal occipital crests arising and diverging inferiorly near the posterolateral borders of foramen magnum. The brain from these cadavers appeared grossly normal with no defect of the vermis. Neurosurgeons and neuroradiologists should be aware of such variations, as these could be potential sources of hemorrhage during suboccipital approaches or may lead to erroneous interpretations of imaging of the posterior cranial fossa.

An anomalous belly of sternothyroid muscle and its significance

The sternothyroid muscle and other infrahyoid muscles play a vital role in the process of vocalization, swallowing and mastication by mobilizing the hyoid bone and thyroid cartilage. During routine dissection of a 70-year-old male cadaver, we observed an anomalous sternothyroid muscle. It was arising from the posterior surface of the manubrium sterni and partly from the cartilage of the first rib. After a distance of 3.3 cm, the belly of sternothyroid muscle was divided into lateral and medial fibers. The lateral belly was inserted above the oblique line on the lamina of the thyroid cartilage, but the medial additional belly turned into a tendon, which was crossing over the thyroid artery and inserted to the hyoid bone and intermediate tendon of digastric muscles. The superior thyroid artery was below the above tendon on its way to the thyroid gland. The muscle was innervated by a branch from the ansa cervicalis.

Morphometry of posterior cerebral artery: embryological and clinical significance

Posterior cerebral artery, terminal branch of basilar artery joins the posterior communicating artery to help complete the circulus arteriosus cerebri in human beings. A study of 89 formalin-fixed brain specimen of either sex and of Indian origin has showed that the mean length and diameter of the posterior cerebral artery was 6.75 +/- 1.482 mm and 1.7 +/- 0.7 mm respectively. Anomalous origin of the posterior cerebral artery was the only variation found during the present study. The incidence of occurrence of the particular variant was 2.2%. The variation did not have any sex or side predilection.

The palmaris longus muscle: its anatomic variations and functional morphology

The functional morphology and evolution of the superficial forearm flexor, the palmaris longus, have long fascinated kinesiologists, physical anthropologists and anatomists alike. The anomalies, agenesis, variations and polymorphic presentation of the muscle, coupled with its biomechanical role in the performance of flexion and supination through distal articulations in the upper limb, have formed the base for many studies found in medical literature. We present data from published sources, along with our observations on the kinetics of palmaris longus, drawn from a series of dissections done on 30 cadavers. Complete agenesis was seen in four limbs. Reversal in the muscle-tendon orientation was seen in two limbs and duplication in one limb. The functional dynamics of the muscle and the clinical implication of its modifications in humans are discussed. We believe that every surgeon must be aware of the variations, since this, otherwise unimportant muscle, provides a very useful graft in tendon surgery.

Multiple variations of the extensor tendons of the forearm

Anatomic variations of the extensor tendons of the forearm are frequent and its knowledge is important to assess the diseased and traumatized hand. During routine cadaveric dissection in the Department of Anatomy, Kasturba Medical College, Mangalore, India, we came across unusual variations in the left upper limb of a 51-years-old male cadaver. The variants are, the complete absence of the extensor pollicis brevis (EPB), the abductor pollicis longus (APL) having six slips of insertion with additional muscle slip from the brachio-radialis (BR). The extensor digitorum communis (EDC) had five tendon slips, the extra tendon splits close to the metacarpo-phalangeal (MP) joint and contribute to the tendons of the ring and little fingers. The number of accessory tendons of APL has functional significance in the development of de Quervain's stenosing tendovaginitis. The present case is unique in the sense that, all the three variations are present in the ipsilateral upper limb. The occurrence of these anomalies and its clinical and embryological significance are discussed.

Additional branches of celiac trunk and its clinical significance

The anatomical variations of the abdominal arteries are important due to its clinical significance. Various types of vascular anomalies are frequently found in human abdominal viscera, during cadaveric dissection and diagnostic radiological imaging. The present report describes a variation in the celiac trunk as found during routine dissection in a 59-year-old male cadaver. The celiac trunk (CT) was unusually lengthy and took origin from the left antero-lateral surface of the abdominal aorta. Altogether, there were five branches, including three classic branches of CT. The left phrenic artery (LPA) was the first branch of the CT. The remaining four branches were left gastric artery (LGA), splenic artery (SA), common hepatic artery (CHA) and gastroduodenal artery (GDA). There was an arterial loop between the posterior branches of the superior pancreatico-duodenal artery (SPDA), arising from the GDA, and the posterior branch of the inferior pancreatico-duodenal artery (IPDA), arising from the superior mesenteric artery (SMA). The arterial loop formed by the above arteries, supplied the head of the pancreas and duodeno-jejunal flexure. The embryological and clinical significance of above variations has been described.