SARS-CoV-2 Omicron XBB lineage spike structures, conformations, antigenicity, and receptor recognition

A recombinant lineage of the SARS-CoV-2 Omicron variant, named XBB, appeared in late 2022 and evolved descendants that successively swept local and global populations. XBB lineage members were noted for their improved immune evasion and transmissibility. Here, we determine cryo-EM structures of XBB.1.5, XBB.1.16, EG.5 and EG.5.1 spike (S) ectodomains to reveal reinforced 3-RBD-down receptor inaccessible closed states mediated by interprotomer receptor binding domain (RBD) interactions previously observed in BA.1 and BA.2. Improved XBB.1.5 and XBB.1.16 RBD stability compensated for stability loss caused by early Omicron mutations, while the F456L substitution reduced EG.5 RBD stability. S1 subunit mutations had long-range impacts on conformation and epitope presentation in the S2 subunit. Our results reveal continued S protein evolution via simultaneous optimization of multiple parameters including stability, receptor binding and immune evasion, and the dramatic effects of relatively few residue substitutions in altering the S protein conformational landscape.

Vaccine induction of CD4-mimicking HIV-1 broadly neutralizing antibody precursors in macaques

The CD4-binding site (CD4bs) is a conserved epitope on HIV-1 envelope (Env) that can be targeted by protective broadly neutralizing antibodies (bnAbs). HIV-1 vaccines have not elicited CD4bs bnAbs for many reasons, including the occlusion of CD4bs by glycans, expansion of appropriate naive B cells with immunogens, and selection of functional antibody mutations. Here, we demonstrate that immunization of macaques with a CD4bs-targeting immunogen elicits neutralizing bnAb precursors with structural and genetic features of CD4-mimicking bnAbs. Structures of the CD4bs nAb bound to HIV-1 Env demonstrated binding angles and heavy-chain interactions characteristic of all known human CD4-mimicking bnAbs. Macaque nAb were derived from variable and joining gene segments orthologous to the genes of human VH1-46-class bnAb. This vaccine study initiated in primates the B cells from which CD4bs bnAbs can derive, accomplishing the key first step in the development of an effective HIV-1 vaccine.

Biosynthesis of silver nanoparticles using nitrate reductase from Aspergillus terreus N4 and their potential use as a non-alcoholic disinfectant

Green technology has been developed for the quick production of stabilized silver nanoparticles (AgNPs), with the assistance of nitrate reductase from an isolated culture of Aspergillus terreus N4. The organism's intracellular and periplasmic fractions contained nitrate reductase, with the former demonstrating the highest activity of 0.20 IU/g of mycelium. When the fungus was cultivated in a medium comprising 1.056% glucose, 1.836% peptone, 0.3386% yeast extract, and 0.025% KNO3, the greatest nitrate reductase productivity of 0.3268 IU/g was achieved. Statistical modeling via response surface methodology was used to optimize the enzyme production. The periplasmic and intracellular enzyme fractions were found to convert Ag+ to Ag0, initiating synthesis within 20 min, with predominant nanoparticle sizes between 25 and 30 nm. By normalizing the effects of temperature, pH, AgNO3 concentration, and mycelium age with a variable shaking period for enzyme release, the production of AgNPs with the periplasmic fraction was optimized. The synthesis of nanoparticles occurred at temperatures of 30, 40, and 50 °C, with the highest yield observed at 40 and 50 °C during shorter incubation periods. Similarly, the nanoparticles were synthesized at pH levels of 7.0, 8.0, and 9.0, with the greatest production observed at pH 8.0 and 9.0 at lower incubation periods. The antimicrobial activity of AgNPs was demonstrated against common foodborne pathogens, including Staphylococcus aureus and Salmonella typhimurium, indicating their potential as non-alcoholic disinfectants.

Rational mutagenesis of Thermobifida fusca cutinase to modulate the enzymatic degradation of polyethylene terephthalate

Thermobifida fusca cutinase (TfCut2) is a carboxylesterase (CE) which degrades polyethylene terephthalate (PET) as well as its degradation intermediates [such as oligoethylene terephthalate (OET), or bis-/mono-hydroxyethyl terephthalate (BHET/MHET)] into terephthalic acid (TPA). Comparisons of the surfaces of certain CEs (including TfCut2) were combined with docking and molecular dynamics simulations involving 2HE-(MHET)_3, a three-terephthalate OET, to support the rational design of 22 variants with potential for improved generation of TPA from PET, comprising 15 single mutants (D12L, E47F, G62A, L90A, L90F, H129W, W155F, ΔV164, A173C, H184A, H184S, F209S, F209I, F249A, and F249R), 6 double mutants [H129W/T136S, A173C/A206C, A173C/A210C, G62A/L90F, G62A/F209I, and G62A/F249R], and 1 triple mutant [G62A/F209I/F249R]. Of these, nine displayed no activity, three displayed decreased activity, three displayed comparable activity, and seven displayed increased (~1.3- to ~7.2-fold) activity against solid PET, while all variants displayed activity against BHET. Of the variants that displayed increased activity against PET, four displayed more activity than G62A, the most-active mutant of TfCut2 known till date. Of these four, three displayed even more activity than LCC (G62A/F209I, G62A/F249R, and G62A/F209I/F249R), a CE known to be ~5-fold more active than wild-type TfCut2. These improvements derived from changes in PET binding and not changes in catalytic efficiency.

Functional HIV-1/HCV cross-reactive antibodies isolated from a chronically co-infected donor

Despite prolific efforts to characterize the antibody response to human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) mono-infections, the response to chronic co-infection with these two ever-evolving viruses is poorly understood. Here, we investigate the antibody repertoire of a chronically HIV-1/HCV co-infected individual using linking B cell receptor to antigen specificity through sequencing (LIBRA-seq). We identify five HIV-1/HCV cross-reactive antibodies demonstrating binding and functional cross-reactivity between HIV-1 and HCV envelope glycoproteins. All five antibodies show exceptional HCV neutralization breadth and effector functions against both HIV-1 and HCV. One antibody, mAb688, also cross-reacts with influenza and coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We examine the development of these antibodies using next-generation sequencing analysis and lineage tracing and find that somatic hypermutation established and enhanced this reactivity. These antibodies provide a potential future direction for therapeutic and vaccine development against current and emerging infectious diseases. More broadly, chronic co-infection represents a complex immunological challenge that can provide insights into the fundamental rules that underly antibody-antigen specificity.

Counter-intuitive enhancement of degradation of polyethylene terephthalate through engineering of lowered enzyme binding to solid plastic

Degradation of solid polyethylene terephthalate (PET) by leaf branch compost cutinase (LCC) produces various PET-derived degradation intermediates (DIs), in addition to terephthalic acid (TPA), which is the recyclable terminal product of all PET degradation. Although DIs can also be converted into TPA, in solution, by LCC, the TPA that is obtained through enzymatic degradation of PET, in practice, is always contaminated by DIs. Here, we demonstrate that the primary reason for non-degradation of DIs into TPA in solution is the efficient binding of LCC onto the surface of solid PET. Although such binding enhances the degradation of solid PET, it depletes the surrounding solution of enzyme that could otherwise have converted DIs into TPA. To retain a subpopulation of enzyme in solution that would mainly degrade DIs, we introduced mutations to reduce the hydrophobicity of areas surrounding LCC's active site, with the express intention of reducing LCC's binding to solid PET. Despite the consequent reduction in invasion and degradation of solid PET, overall levels of production of TPA were ~3.6-fold higher, due to the partitioning of enzyme between solid PET and the surrounding solution, and the consequent heightened production of TPA from DIs. Further, synergy between such mutated LCC (F125L/F243I LCC) and wild-type LCC resulted in even higher yields, and TPA of nearly ~100% purity.

N-Terminal Extensions Appear to Frustrate HU Heterodimer Formation by Strengthening Intersubunit Contacts and Blocking the Formation of a Heterotetrameric Intermediate

HU is a bacterial nucleoid-associated protein. Two homologues, known as HU-A, and HU-B, are found in Escherichia coli within which the early, late, and stationary phases of growth are dominated by HU-AA, HU-BB, and HU-AB dimers, respectively. Here, using genetic manipulation, mass spectrometry, spectroscopy, chromatography, and electrophoretic examination of glutaraldehyde-mediated cross-linking of subunits, in combination with experiments involving mixing, co-expression, unfolding, and refolding of HU chains, we show that the spontaneous formation of HU-AB heterodimers that is reported to occur upon mixing of wild-type HU-AA and HU-BB homodimers does not occur if chains possess N-terminal extensions. We show that N-terminal extensions interfere with the conversion of homodimers into heterodimers. We also show that heterodimers are readily formed at anticipated levels by chains possessing N-terminal extensions in vivo, when direct chain-chain interactions are facilitated through production of HU-A and HU-B chains from proximal genes located upon the same plasmid. From the data, two explanations emerge regarding the mechanism by which N-terminal extensions happen to adversely affect the conversion of homodimers into heterodimers. (1) The disappearance of the α-amino group at HU's N-terminus impacts the intersubunit stacking of β-sheets at HU's dimeric interface, reducing the ease with which subunits dissociate from each other. Simultaneously, (2) the presence of an N-terminal extension appears to sterically prevent the association of HU-AA and HU-BB homodimers into a critically required, heterotetrameric intermediate (within which homodimers could otherwise exchange subunits without releasing monomers into solution, by remaining physically associated with each other).

HU-AB simulacrum: Fusion of HU-B and HU-A into HU-B-A, a functional analog of the Escherichia coli HU-AB heterodimer

In enteric bacteria such as Escherichia coli, there are two homologs of the DNA-binding nucleoid associated protein (NAP) known as HU. The two homologs are known as HU-A and HU-B, and exist either in the form of homodimers (HU-AA, or HU-BB) or as heterodimers (HU-AB), with different propensities to form higher-order oligomers. The three different dimeric forms dominate different stages of bacterial growth, with the HU-AB heterodimer dominating cultures in the stationary phase. Due to similarities in their properties, and the facile equilibrium that exists between the dimeric forms, the dimers are difficult to purify away from each other. Although HU-AA and HU-BB can be purified through extensive ion-exchange chromatography, reestablishment of equilibrium interferes with the purification of the HU-AB heterodimer (which constitutes ∼90% of any population with equal numbers of HU-B and HU-A chains). Here, we report the creation of a functional analog of HU-AB that does not appear to partition to generate any minority populations of HU-AA or HU-BB. The analog was constructed through genetic fusion of the HU-B and HU-A chains into a single polypeptide (HU-B-A) with a glycine/serine-rich linker of 11 amino acids separating HU-B from HU-A, and a histidine tag at the N-terminus of HU-B. HU-B-A folds to bind 4-way junction DNA, and displays a significant tendency to form dimers (i.e., analogs of HU tetramers), and a higher thermodynamic stability than HU-BB or HU-AA, thus explaining why it dominates mixtures of HU-B and HU-A chains.

The DNA-binding protein HU is a molecular glue that attaches bacteria to extracellular DNA in biofilms

In biofilms, bacteria that possess a negatively charged surface are embedded within a matrix of polymers consisting mainly of negatively charged extracellular DNA (e-DNA). In all likelihood, a multivalent positively charged substance, for example, a basic protein, exists within biofilms to neutralize charge–charge repulsions and act as a ‘glue’ attaching negatively charged bacteria to negatively charged e-DNA; however, no protein capable of doing so has yet been identified. We decided to investigate whether a highly abundant nucleoid-associated histone-like protein (HU) happens to be the glue in question. In recent years, HU has been shown to possess qualities that could be considered desirable in the proposed glue, for example, (a) availability in association with e-DNA; (b) multivalent DNA binding; (c) non–sequence-specific DNA-binding; (d) enhancement of biofilm formation upon exogenous addition, and (e) disruption of biofilms, upon removal by HU–cognate antibodies. Geometric considerations suggest that basic residues in HU's canonical and noncanonical DNA-binding sites can interact with sugar-linked terminal phosphates in lipopolysaccharide (LPS) molecules in bacterial outer membranes. Here, using genetic, spectroscopic, biophysical–chemical, microscopy-based, and cytometry-based experiments, we demonstrate that HU's DNA-binding sites also bind to LPS, that this facilitates DNA–DNA, DNA–LPS, and LPS–LPS interactions, and that this facilitates bacterial clumping and attachment of bacteria to DNA. Exogenous addition of HU to bacteria in (nonshaken) cultures is shown to cause cells to become engulfed in a matrix of DNA, potentially arising from the lysis of bacteria with vulnerable cell walls (as they strain to grow, divide, and move away from each other, in opposition to the accreting influence of HUs).

A novel protein-engineered dsDNA-binding protein (HU-Simulacrum) inspired by HU, a nucleoid-associated DNABII protein

HU, a DNA-binding protein, has a helical N-terminal region (NTR) of ∼44 residues and a beta strand- and IDR-rich C-terminal region (CTR) of ∼46 residues. CTR binds to DNA through (i) a clasp (two arginine/lysine-rich, IDR-rich beta hairpins that bind to phosphate groups in the minor groove), (ii) a flat surface (comprising four antiparallel beta strands that abut the major groove), and (iii) a charge cluster (two lysine residues upon a short C-terminal helix). HU forms a dimer displaying extensive inter-subunit CTR-CTR contacts. A single-chain simulacrum of these contacts (HU-Simul) incorporating all DNA-binding elements was created by fusing together the CTRs of Escherichia coli HU-A and Thermus thermophilus HU. HU-Simul is monomeric, binds to dsDNA and cruciform DNA, but not to ssDNA.

Epidemiological and clinical profile of Influenza A(H1N1) pdm09 in Odisha, eastern India

Epidemic of flu is highly contagious and it spreads through air. In 2009 H1N1 influenza virus emerged after reassortment of North American TRIG and Eurasia Avian like virus of swine and started epidemic in Mexico. The first cases were reported from Hyderabad city on 16th May 2009 in India that spread rapidly within a short span of time. During this period large population of Odisha situated at the eastern side of India was also affected and incidences of H1N1 cases were recorded through state Government surveillance system. In this study real time RT-PCR based diagnosis was conducted for the throat swabs collected from suspected H1N1 cases in Odisha during 2009–2017. A total of 2872 throat swabs were received from 23 different Government and private hospitals and 21.1% positivity was confirmed. The disease affected mostly 46–60 years age group, males (50.6%) being more affected. The clinical features had shown that fever with cough (89.6%) was the most common symptom followed by shortness of breath (72.7%). Post monsoon was the peak season in which most of the cases were reported. Neurological signs, pregnancy, diabetes and hypertension were found to be risk factors for H1N1. The case fatality rate (CFR) was 15%.

Molecular and phylogenetic analysis of the dengue strains circulating in Odisha, India

Dengue has emerged as a major public health challenge in terms of both changing clinical pattern and epidemiological features. The state of Odisha reported first dengue epidemic in the year 2010 and this continued each year in epidemic form during post monsoon period gradually becoming an endemic phenomenon. Present study depicts the changing epidemiological and clinical pattern of dengue with reference to its serotypes and genotypes. The study included 5320 suspected dengue cases from different health facilities of the state during 2010-2017. Dengue NS1 antigen and IgM antibody was done through ELISA. Serotyping was done through RTPCR by amplifying a part of core-pre-membrane gene (CprM) followed by sequencing and phylogenetic analysis. Dengue IgM antibody in 17.7% cases and NS1 antigen in 53.20% cases was detected. Dengue serotype 2 (DEN-2) was the only serotype detected in 2010 and 2011 where as all four serotypes 1, 2, 3, 4 were detected in 2012-2017, DEN-2 being dominant but in 2017 DEN-3 was found to be dominant. Phylogenetic analysis revealed genotype IV of DEN-2 and genotype III of DEN-1 and DEN-3 circulating in this region. In 6 cases involvement of DEN-2 in clinically evident encephalitis cases is an important observation in this region and needs public health attention. High prevalence of dengue was observed without any previous reported outbreaks in the state with increased number of cases from 2010 to 2012 affecting both urban and rural areas. High incidence in 2012 was due to co-circulation of more than one serotype which continued in the following years. Severity in some cases was associated with mixed infection but in most cases it was mild indicating the endemic nature of the virus in most parts of Odisha.

Hepatic venous outflow tract obstruction: treatment outcomes and development of a new prognostic score

BACKGROUND

Results of endovascular interventions in hepatic venous outflow tract obstruction (HVOTO) have been reported from limited studies. Treatment outcomes and prognostic scores need further validation.

AIM

To evaluate treatment outcomes and prognostic scores for hepatic venous outflow tract obstruction in an Indian population.

METHODS

Consecutive patients with hepatic venous outflow tract obstruction diagnosed at a tertiary centre were included. Technical success and clinical response after endovascular interventional therapy were documented. Predictors of survival were assessed with Cox-proportional model. A new score was derived from the factors significant on multivariate analysis and compared with Child-Turcotte-Pugh, model for end-stage liver disease (MELD), Rotterdam prognostic index (PI) and Budd-Chiari syndrome-transjugular intrahepatic portosystemic shunt ( BCS-TIPSS) PI.

RESULTS

Three hundred and thirty-four patients (56.6% males), median age 24 (3-62) years were included. Hepatic vein was the commonest site of block-isolated hepatic vonous block in 48%, combined hepatic venous-inferior vena cava block in 46%. Endovascular interventional therapy was performed in 233/334 (70%) with 90% technical success. Clinical response was complete in 166 (71.2%), partial in 58 (24.9%) and no response in nine (3.9%). Majority of cases with HV block did not require TIPSS and could be treated with angioplasty (with/without stenting). On Cox-proportional multivariate analysis, Child class C and response to intervention were independent predictors of outcome and used to derive the All India Institute of Medical Sciences (AIIMS) hepatic venous outflow tract obstruction score. The 5-year survival was 92% (95% CI, 81-97%) for score ≤3, 79% (95%CI, 63-88%) for score >3 and ≤4, and 39% (95% CI, 21-57%) for score >4. The performance of AIIMS hepatic venous outflow obstruction score was superior to other prognostic indices.

CONCLUSIONS

Advanced Child class and no response to intervention are associated with poor outcomes. The All India Institute of Medical Sciences hepatic venous outflow tract obstruction score predicts survival better than other prognostic scores.

GW627368X inhibits proliferation and induces apoptosis in cervical cancer by interfering with EP4/EGFR interactive signaling

PGE2, the major product of cyclooxygenases implicated in carcinogenesis, is significantly upregulated in cervical cancer. PGE2 via prostanoid receptor EP4 stimulates proliferation and motility while inhibiting apoptosis and immune surveillance. It promotes angiogenesis by stimulating the production of pro-angiogenic factors. The present study demonstrates GW627368X, a highly selective competitive EP4 antagonist, which hinders cervical cancer progression by inhibiting EP4/epithelial growth factor receptor (EGFR) interactive signaling. GW627368X reduced protein kinase A (PKA) phosphorylation which in turn leads to decreased cAMP response element-binding protein (CREB) activation. Decreased PKA phosphorylation also directly enhanced Bax activity and in part reduced glycogen synthase kinase 3 (GSK3)β phosphorylation. Owing to the interactive signaling between EP4 and EGFR, GW627368X lowered EGFR phosphorylation in turn reducing Akt, mitogen-activated protein kinase (MAPK) and GSK3β activity significantly. Sublethal dose of GW627368X was found to reduce the nuclear translocation of β-catenin in a time dependent manner along with time-dependent decrease in cytoplasmic as well as whole-cell β-catenin. Decreased CREB and β-catenin transcriptional activity restricts the aberrant transcription of key genes like EP4, cyclooxygenase (COX)-2, vascular endothelial growth factor and c-myc, which ultimately control cell survival, proliferation and angiogenesis. Reduced activity of EGFR resulted in enhanced expression of 15-hydroxyprostaglandin dehydrogenase increasing PGE2 degradation thereby blocking a positive feedback loop. In xenograft model, dose-dependent decrease in cancer proliferation was observed characterized by reduction in tumor mass and volume and a marked decrease in Ki67 expression. A diminished CD31 specific staining signified decreased tumor angiogenesis. Reduced expression of pAkt, pMAPK, pEGFR and COX-2 validated in vitro results. GW627368X therefore effectively inhibits tumor survival, motility, proliferation and angiogenesis by blocking EP4/EGFR interactive signaling. EP4 is a potent therapeutic target in cervical cancer and can be explored in combination with conventional therapies to attain superior outcomes and to overcome complications associated with organ toxicities, therapeutic resistance and disease relapse.

Adenoid cystic carcinoma in trachea: A rare presentation

Primary tracheal tumors are rare. Adenoid cystic carcinoma of trachea is even rarer. It occurs as a polypoidal mass in trachea presenting with dyspnea and respiratory distress due to tracheobronchial obstruction. We report a case of young male presenting with dyspnea for some time. CT scan revealed mass in trachea obliterating its lumen. Histopathological examination conirmed the diagnosis.

Surgical Results of Non-small Cell Lung Cancer in Nepal

INTRODUCTION

Surgery remains the only curative modality for early stage of Non small cell lung caner (NSCLC). We reviewed overall scenario of lung cancer and surgical results in Nepal.

METHODS

1000 patients with the pathological diagnosis of lung cancer were analyzed to summarize the overall scenario of lung cancer. 157 NSCLC patients underwent pulmonary resection. cIA, IB, IIA, IIB, IIIA (N1) underwent surgery as initial modality of treatment. cIIIA (N2) patients were taken for surgery after neoadjuvant chemo/ chemoradiation.

RESULTS

Analysis of 1000 patients showed squamous cell carcinoma in 41.3%, incurable stage (IIIB/ IV) in 66.8% and rate of curative resection in 6.7% cases. Surgery as a single modality of treatment was used in 38%. Neoadjuvant Chemo/ chemoradiation/ radiation followed by surgery and surgery followed by chemo/ chemoradiation/ radiation was done in 12% and 50%, respectively. In-hospital mortality was 2% (post pneumonectomy: 5.5%; post lobectomy: 1.5%; post sublobar resection: 0%). R0 resction was achieved in 91% cases. Median survival and 5-year overall survival were 36 months and 18%, respectively. Better survival was achieved in pI-II vs pIII/ IV, pN0-1 vs pN2 and pR0 vs pR+ (p <0.05).

CONCLUSIONS

Earlier stage (pI-II), R0 resection and pathological pNo-1 has the best five year overall survival in Nepalese patients with NSCLC as well.

Histopathological study of placentae in low birth weight babies in India

Background:

The antenatal health-care given to pregnant women has great influence on the rates of perinatal death and morbidity. Amongst the different causes of perinatal mortality, low birth weight (LBW) is the single most significant factor therefore placenta from all the LBW babies (LBWB) should be examined routinely to find out the likely cause.

Aims:

The aims of this study were to assess the pathological changes in the placenta in association with LBWB.

Materials and Methods:

This is a Case control study performed at Medical College Allahabad,(MLN) India. In this study, 90 placentae were included. 30 placentae from full-term vaginally delivered babies, weighing more than 2500 g were included as the control group. 60 placentae belonged to babies whose birth weight was less than 2500 g (LBW). Weight of the baby was taken within the 1^st h of birth and Apgar score was noted. Gross and microscopic examination of placentae was done. Statistical correlation of was carried out between them by using SPSS 18 version. Chi-square test with or without yate's correction was used as and when required. P < 0.05 was taken as critical level of significance.

Results:

Placenta was circum-marginal in both groups. Attachment of cord was mainly central in the control group 90% (27/30), whereas eccentric attachment was prominent in patient group 66.67% (40/60). The difference was statistically significant (P < 0.001). Calcification and sub-chorionic fibrin deposition was seen in significantly higher numbers of placentae from patients than controls (P < 0.01) infarction and meconium staining were seen in placentae from patients only. Histologically placental ischemia, infarction and calcification were seen in significantly higher number of patients (P < 0.001, P < 0.001 and < 0.01 respectively). Fibrinoid necrosis, stromal fibrosis, placental dysmaturity and obstructive vasculopathy were seen in placentae from patients only.

Conclusion:

Placental pathology among LBW infants was high in comparison to control group. The findings suggest that chronic ischemia and associated secondary changes probably lead to improper perfusion and LBWB.

Polymeric nanoparticle formulation of octapeptide (NP-OP): in vitro release and in vivo effect in common marmosets, Callithrix jacchus Linn

Octapeptide (OP)/FSH-Receptor Binding Inhibitor-8 (FRBI-8), is a synthetic peptide corresponding to N-terminal sequence of purified fraction of Follicle Stimulating Hormone Binding-Inhibitor (FSHBI), isolated earlier from human ovarian follicular-fluid. In order to avoid the repeated drug-administration, OP-loaded, polymeric polylactide (PLA) nanoparticle formulation (NP-OP), was developed using multiple-emulsion technique. This yielded an average particle size of 120 nm with 70% encapsulation-efficiency. In vitro release profile of NP-OP showed sustained release of OP for 21 days. In vivo anti-fertility studies were conducted in marmosets. Results indicated that control animals conceived in the same cycle while two of three treated animals failed to conceive in treatment cycle. The in vivo studies thus corroborate with in vitro release of OP, demonstrating its anti-fertility activity in 66% of animals.

Transnasal trans-sphenoidal endoscopic repair of CSF leak secondary to invasive pituitary tumours using a nasoseptal flap

Cerebrospinal fluid (CSF) leak following initiation of Dopamine agonist therapy for macroprolactinomas, although uncommon, has been described previously in the literature. Traditional management includes primary repair of the defect using either fat or fascia lata in conjunction with lumbar drain insertion. In this case series we outline two cases of CSF leak secondary to invasive pituitary tumour that were repaired successfully using a nasoseptal flap. We believe that this form of repair is effective and associated with minimal morbidity.

Eight-year experience in esophageal cancer surgery

AIM

Esophageal cancer remains a major and lethal health problem. In Nepal, not much has been explored about its management. The aim of this study was to conduct a retrospective review of esophageal cancer patients undergoing surgery or combined modality treatment at a cancer hospital in Nepal.

MATERIALS AND METHODS

Resectable cases were treated primarily with surgery. Locally advanced cases with doubtful or obviously unresectability underwent preoperative chemo/radiation or chemoradiation followed by surgery.

RESULTS

Among 900 patients, 103 were treated with curative intent. Mean age of patients was 54 years, and 100% of the patients presented with complaint of dysphagia. Surgery as a single modality of treatment was done in 57% of cases, and the remaining underwent combined modality treatment. Transthoracic and transhiatal approaches were used in 95% and 5% of cases, respectively. Nodal sampling, two-field (2-FD), and three-field lymphadenectomy (3-FD) were done in 18%, 59%, and 20% of cases, respectively. A majority of patients had pathological stage III disease (46.6%). In-hospitality mortality was 5%, and anastomotic leakage rate was 14%. In 87% of patients, R0 resection was achieved. Overall, 4-year survival was 20%. A R0 resection, early-stage disease and 3-FD favored the survival advantage (P < 0.05).

CONCLUSION

The mortality, complication, and survival results were in the acceptable range. R0 resection and radical nodal dissection should be standard practice.

Giant Cell Tumor Arising from Anterior Arc of First Rib- A Rare Presentation

We report a case of Giant Cell Tumor (GCT) arising from anterior are of first rib along with literature review which was treated with excision of rib through its normal margin along with tumor mass. GCT of rib is rare and if found mostly arises from the posterior aspect. However, GCT should be considered as differential diagnosis when bony mass is present in the anterior are of rib. It poses surgical challenge for excision because of the delicate and vital neurovascular structures passing above it between clavicle and first rib. Keywords: first rib, giant cell tumor.

Giant cell tumor arising from anterior arc of first rib: a rare presentation

We report a case of Giant Cell Tumor (GCT) arising from anterior are of first rib along with literature review which was treated with excision of rib through its normal margin along with tumor mass. GCT of rib is rare and if found mostly arises from the posterior aspect. However, GCT should be considered as differential diagnosis when bony mass is present in the anterior are of rib. It poses surgical challenge for excision because of the delicate and vital neurovascular structures passing above it between clavicle and first rib.

Use of greater omentum in thoracic onco-surgery

BACKGROUND

Omentum is well known for its immunocompetence and good blood supply; and therefore, is being used in various complex thoracic procedures. Specially, in situations when staplers, sealants and total parenteral nutrition may not be used because of financial constraints, omentum may prove very helpful in preventing post-operative fatal complications.

METHODS

A retrospective review of 61 patients was undertaken. Patients were categorized into two groups. In group I, omentum was sutured to the anastomosis for prophylaxis of leak from gastro-oesophagectomy after radical surgery for cancer of cardia and oesophagus. In group II, it was used for therapeutic purpose, to control diffuse air leak from lung parenchyma after chest wall and invaded lung resection for malignant chest wall tumours (subgroup A) and treatment of post pneumonectomy bronchopleural fistula for NSCLC of right lung (subgroup B). Gastro-oesophagectomy, closure of bronchial stump and suturing of lung parenchyma after wedge resection was done with manual suturing technique only.

RESULTS

Group I: There were 57 patients with the diagnosis of cancer of cardia and oesophagus, who underwent radical surgery. Transthoracic approach was used in 96.5% patients, whereas 3.5% patients underwent transhiatal resection. Anastomotic level was located in chest in 68.4% and in neck in 31.6% patients. The leakage rate was 5.4%. Group II: There were three patients in subgroup A, all with lesions located in left side of chest wall. There was one patient in subgroup B. Chest tube was removed after a mean time of 2 days and after 4 days in subgroup A and B, respectively. There was 1 mortality (1.6%) secondary to chylothorax.

CONCLUSION

Use of pedicled omentum appears to be a very simple technique to prevent the anastomotic leak after radical surgery for cancer of cardia and oesophagus, and to seal the diffuse parenchymal pulmonary leak after various procedures in thorax.

Clinical study of sentinel lymph node biopsy in early uterine cervical carcinoma

BACKGROUND

Radical hysterectomy and complete pelvic lymphadenectomy is the standard treatment for early cervical carcinoma. But the rate of pelvic and paraaortic nodal metastasis is found to be low, pointing that most of the patients possibly undergo unnecessary nodal dissection.

AIM

To study the value of sentinel lymph nodes (SLNs) in prediction of the pelvic lymph node status and to determine the significance of SLN detection in pelvic lymph node dissection in patients with early stage cervical carcinoma.

SETTINGS AND DESIGN

Retrospective study.

METHODS

From August 2002 to August 2004, 20 patients with early stage cervical carcinoma, planned to undergo radical hysterectomy and extensive pelvic lymph node dissection received an intracervical injection of a blue dye to identify and perform resection of SLN. The SLNs were pathologically compared with non-SLNs with frozen section, paraffin section, and anti-cytokeratin immunohistochemical staining.

RESULTS

Out of 20 patients, SLNs were detected in 15 patients. A total of 46 SLNs were identified and the mean was 3 per patient. The detection rate of SLN was 75%. Sensitivity, specificity and accuracy of the SLN biopsy were 75%, 100% and 95%, respectively.

CONCLUSION

SLN detection can predict the pelvic lymph node status in early stage cervical carcinoma, but the feasibility and safety of this technique to substitute conventional surgical modality should be evaluated by large series of prospective studies.

How we performed chest wall reconstruction: analysis 31 cases

OBJECTIVE

To see the results of patients who underwent chest wall resection and reconstruction (CWRR).

SETTING AND DESIGN

Retrospective descriptional study.

MATERIAL AND METHODS

We retrospectively reviewed all patients who underwent CWRR at Xingtai People's Hospital in China and B.P. Koirala Memorial Cancer Hospital in Nepal. A total of 31 patients were reviewed. Among them, 20 were male and 11 female. The median age was 63 years. The indications for resection were primary chest wall tumor in 21 patients (67.7%), lung cancer with invasion of chest wall 6 (19.4%), recurrence of breast cancer 2(6.3%), radiation necrosis 1(3.2%) and skin cancer 1(3.2%).

RESULTS

The mean number of rib resected was 3.6 ribs, which induced a mean defect of 97.1 cm2. Concomitant resection was done in 13 patients, including lung resection 10, partial resection of diaphragm 2, and partial sternectomy 1. Seven patients underwent soft tissue reconstruction (STR) alone and 5 patients skeletal reconstruction (SR) alone. Simultaneous SR and STR were performed in 19 patients. Three patients (9.7%) developed postoperative complications. The median survival period was 22 months.

CONCLUSION

Primary chest wall tumor and lung cancer invading chest wall are the most common diseases indicating CWRR. Simultaneous bony and soft tissue reconstruction was reliable for chest wall reconstruction in most cases and prevents postoperative complications.

The Ayurvedic medicines Haritaki, Amala and Bahira reduce cholesterol-induced atherosclerosis in rabbits

Four groups of 25 rabbits each, were studied to determine the effect of Haritaki (Terminalia chebula), Amla (Emblica officinalis) and Bahira (Terminalia belerica) on cholesterol-induced hypercholesteolaemia and atherosclerosis. The control group was fed with cholesterol alone; the Haritaki group received Haritaki and cholesterol; the Bahira group received Bahira and cholesterol; and the Amla group received Amla and cholesterol for 16 weeks. Cholesterolaemia was significantly less (P less than 0.001) in the Haritaki group (166 mg/dl), the Bahira group (240 mg/dl) and the Amla group (205 mg/dl) than in the control group (630 mg/dl). The Haritaki group had significantly less cholesterolaemia (P less than 0.001) as compared to the Bahira and Amla groups. Aortic sudanophilia was significantly less (P less than 0.001) in the Haritaki group (6%), the Bahira group (16%), and the Amla group (12%) than in the control group (38%). The cholesterol contents of the liver and aorta, respectively, were significantly less in the Haritaki group (46 mg/100 g, 28 mg/100 g), the Bahira group (78 mg/100 g, 72 mg/100 g) and the Amla group (46 mg/100 g, 42 mg/100 g), than in the control group (604 mg/100 g, 116 mg/100 g). Among the drug-fed groups, the Haritaki group had significantly lower degrees of sudanophilia and cholesterol content of aorta and liver (P less than 0.001) as compared to the Bahira and Amla groups. Although all three drugs reduced serum cholesterol, aortic sudanophilia and cholesterol contents of liver and aorta, their effects were in ascending order of magnitude. The drugs did not influence serum triglyceride levels, euglobulin clot lysis time or platelet adhesiveness.(ABSTRACT TRUNCATED AT 250 WORDS)

A rare case of Castleman's disease presenting as a pulmonary mass mimicking pulmonary malignancy

Castleman disease is a rare disorder of the lymphoid system characterized by noncancerous growths that may develop in lymph node tissues throughout the body. Most often this occurs in the neck, mediastinum, and abdomen where lymph nodes aggregate. The etiology is thought to be due to antigenic hyperstimulation of unknown origin. Two histological subtypes are described with different clinical presentations and therapeutic implications. Diagnosis is frequently accomplished only by histological analysis after surgery since no specific features have been found in imaging studies. Surgical excision is both diagnostic and curative in localized forms, whereas additional therapies are required in multicentric forms. Here we describe a case of castleman disease adjacent to the right pulmonary hilum loosely adherent to the interlobar branch of the right pulmonary artery that mimicked tuberculosis or malignancy in a 30-year-old man who underwent curative surgical removal of the mass. Keywords: Castleman disease; Pulmonary malignancy; IL-6; HHV-8; Kaposi sarcoma DOI: 10.3126/jpn.v1i1.4456 Journal of Pathology of Nepal (2011) Vol.1, 63-65